scholarly journals Characterising Residual Limb Morphology and Prosthetic Socket Design Based on Expert Clinician Practice

Prosthesis ◽  
2021 ◽  
Vol 3 (4) ◽  
pp. 280-299
Author(s):  
Alexander Dickinson ◽  
Laura Diment ◽  
Robin Morris ◽  
Emily Pearson ◽  
Dominic Hannett ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Principal Component ◽  
Population Based ◽  
Digital Design ◽  
Residual Limb ◽  
Design Features ◽  
Prosthetic Socket ◽  
Expert Clinician ◽  
Cad Cam ◽  
Successful Design

Functional, comfortable prosthetic limbs depend on personalised sockets, currently designed using an iterative, expert-led process, which can be expensive and inconvenient. Computer-aided design and manufacturing (CAD/CAM) offers enhanced repeatability, but far more use could be made from clinicians’ extensive digital design records. Knowledge-based socket design using smart templates could collate successful design features and tailor them to a new patient. Based on 67 residual limb scans and corresponding sockets, this paper develops a method of objectively analysing personalised design approaches by expert prosthetists, using machine learning: principal component analysis (PCA) to extract key categories in anatomic and surgical variation, and k-means clustering to identify local ‘rectification’ design features. Rectification patterns representing Total Surface Bearing and Patella Tendon Bearing design philosophies are identified automatically by PCA, which reveals trends in socket design choice for different limb shapes that match clinical guidelines. Expert design practice is quantified by measuring the size of local rectifications identified by k-means clustering. Implementing smart templates based on these trends requires clinical assessment by prosthetists and does not substitute training. This study provides methods for population-based socket design analysis, and example data, which will support developments in CAD/CAM clinical practice and accuracy of biomechanics research.

scholarly journals Characterising Residual Limb Morphology and Prosthetic Socket Design based on Expert Clinician Practice

2021 ◽  
Author(s):  
Alexander Dickinson ◽  
Laura Diment ◽  
Robin Morris ◽  
Emily Pearson ◽  
Dominic Hannett ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Principal Component ◽  
Population Based ◽  
Digital Design ◽  
Residual Limb ◽  
Design Features ◽  
Prosthetic Socket ◽  
Expert Clinician ◽  
Cad Cam ◽  
Successful Design

Functional, comfortable prosthetic limbs depend on personalised sockets, currently designed using an iterative, expert-led process, which can be expensive and inconvenient. Computer aided design and manufacturing (CAD/CAM) offers enhanced repeatability, but far more use could be made from clinicians’ extensive digital design records. Knowledge-based socket design using smart templates could collate successful design features and tailor them to a new patient. Based on 67 residual limb scans and corresponding sockets, this paper develops a method of objectively analysing personalised design approaches by expert prosthetists, using machine learning: principal component analysis (PCA) to extract key categories in anatomic and surgical variation, and K-Means Clustering to identify local ‘rectification’ design features. Rectification patterns representing Total Surface Bearing and Patella Tendon Bearing design philosophies are identified automatically by PCA, which reveals trends in socket design choice for different limb shapes that match clinical guidelines. Expert design practice is quantified by measuring the size of local rectifications identified by k-means clustering. Implementing smart templates based on these trends requires clinical assessment by prosthetists and does not substitute training. This study provides methods for population-based socket design analysis, and example data, which will support developments in CAD/CAM clinical practice and accuracy of biomechanics research.

scholarly journals Accuracy Verification of Magnetic Resonance Imaging (MRI) Technology for Lower-Limb Prosthetic Research: Utilising Animal Soft Tissue Specimen and Common Socket Casting Materials

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Mohammad Reza Safari ◽  
Philip Rowe ◽  
Arjan Buis
Keyword(s):  
Surface Area ◽  
Cross Sections ◽  
Lower Limb ◽  
Residual Limb ◽  
Cross Sectional ◽  
Prosthetic Socket ◽  
Semiautomatic Segmentation ◽  
Segmented Images ◽  
Cad Cam ◽  
Volume Measurements

Lower limb prosthetic socket shape and volume consistency can be quantified using MRI technology. Additionally, MRI images of the residual limb could be used as an input data for CAD-CAM technology and finite element studies. However, the accuracy of MRI when socket casting materials are used has to be defined. A number of six, 46 mm thick, cross-sections of an animal leg were used. Three specimens were wrapped with Plaster of Paris (POP) and the other three with commercially available silicone interface liner. Data was obtained by utilising MRI technology and then the segmented images compared to corresponding calliper measurement, photographic imaging, and water suspension techniques. The MRI measurement results were strongly correlated with actual diameter, surface area, and volume measurements. The results show that the selected scanning parameters and the semiautomatic segmentation method are adequate enough, considering the limit of clinical meaningful shape and volume fluctuation, for residual limb volume and the cross-sectional surface area measurements.

scholarly journals Stress Analysis of a Patient-specific Socket Design during Gait Cycle

2019 ◽  
Vol 8 (4) ◽  
pp. 6962-6966
Keyword(s):  
Pressure Distribution ◽  
Computer Aided Design ◽  
Dynamic Condition ◽  
Pressure Sensors ◽  
Lower Limbs ◽  
Patient Specific ◽  
Fused Deposition Modelling ◽  
Residual Limb ◽  
Fused Deposition ◽  
Prosthetic Socket

Transtibial amputation is one of the common surgical procedure involved removal of lower limbs specifically below the knee. The need of amputation was caused by major accidents or diseases. Prosthetic socket was an important part as it kept the residual limb in place. It should allow amputee to perform daily activities without caused any pains. Most amputees reviewed the socket’s design caused pain on their residual limb. This project was purposed to analyse the pressure distribution on the prosthetic socket design. Design of the socket was based on stump’s condition which verified from the hospitals. Autodesk Meshmixer software was used to remodel the socket design from 3D Computer Aided Design (CAD) data of real stump. Pressure sensors measured the pressure exerted due to contact between socket and stump. The measured pressure distribution was analysed according to the pressure tolerant and sensitive areas to avoid the uncomfortable pain. The simulation of socket design was simulated using Finite Element Method (FEM) in ANSYS Static Structural. FEM indicated the behaviour of the socket during static and dynamic condition. Then, prosthetic sockets were fabricated in-house manufacturing process based on Fused Deposition Modelling (FDM) technology using 2.85-mm filament of polyamide nylon (PA). Thus, the tensile properties of the nylon socket material were determined according to ASTM D638. The evaluated stress was 11.30 MPa at the mid-stance that proved the material was highly strength to support the load. The structural integrity of the complete prosthesis socket should be investigated according to ISO 10328 for future improvement

scholarly journals SURFACE MODELING FOR CAD/CAM BASED ON NURBS

2011 ◽  
Vol 14 (4) ◽  
pp. 44-52
Author(s):  
Hien Tat Le ◽  
Hung Xuan Nguyen ◽  
Cang Trong Vo
Keyword(s):  
Computer Aided Design ◽  
Geometric Modeling ◽  
Surface Modeling ◽  
Digital Design ◽  
Nurbs Surface ◽  
Computer Aided ◽  
Modeling Techniques ◽  
Cad Cam ◽  
Numerical Performance ◽  
Aided Design

In the digital design process, surface modeling is required to be as accurate as possible for the effective support of production as well as for numerical performance analysis. This article reviews the geometric modeling techniques, based on non-uniform rational B-spline (NURBS). The NURBS surface can be readily translated into many CAD/CAM packages (Computer Aided Design/Computer Aided Manufacturing), which is more convenient for visualization performance and finite element methods.

A New Proposed Method to Reverse Engineer a Residual Limb for Prosthetic Socket - Procedure, Advantages and Challenges

2016 ◽  
Vol 852 ◽  
pp. 558-563
Author(s):  
Divya Singh ◽  
Richa Pandey
Keyword(s):  
Lower Limb ◽  
Present Model ◽  
Body Part ◽  
Cad Model ◽  
Residual Limb ◽  
Reverse Engineer ◽  
Prosthetic Socket ◽  
Human Body Part ◽  
Cad Cam ◽  
Lower Limb Amputees

A prosthetic replaces any missing human body part visibly and also aims to resume the normal functionality of the part. Reverse engineering extracts information from a present model or available design and develops a new model using advanced CAD tools. Nowadays the reverse engineered part can be combined with rapid prototyping by various software and integration of CAD-CAM platforms. In this paper, a new method to reverse engineer the residual limb information for lower limb amputees, in order to use it for analyzing and developing a prosthetic socket by scanning and developing a CAD model is proposed. Along this are discussed, the advantages and challenges. This work falls in the emerging field of interdisciplinary engineering, combining medical and advanced mechanical engineering on a humanitarian platform

A review of history of CAD/CAM system application in the productionof transtibial prosthetic socket in developing countries (from 1980to 2019)

2021 ◽  
pp. 095441192110352
Author(s):  
Nur Afiqah Hamzah ◽  
Nasrul Anuar Abd Razak ◽  
Mohd Sayuti Ab Karim ◽  
Hossein Gholizadeh
Keyword(s):  
Developing Countries ◽  
Computer Aided Design ◽  
Large Scale ◽  
Digital Fabrication ◽  
Developing Regions ◽  
Prosthetic Socket ◽  
Computer Aided ◽  
Cad Cam ◽  
History Of ◽  
Aided Design

The development of the CAD/CAM (Computer-aided design and computer-aided manufacturing) system has globally changed the fabrication and delivery of prosthetics and orthotics. Furthermore, since the introduction of CAD/CAM in the 1980s, many successful CAD/CAM system are available in the market today. However, less than 20% of amputees have access to digital fabrication technology and large portion of the amputees are from the developing countries. This review designed to examine selected studies from 1980 to 2019 on CAD/CAM systems in the production of transtibial prosthetic sockets. A review was conducted based on articles gathered from Web of Science, Pubmed and Science Direct. From the findings, 92 articles found related to CAD/CAM-derived transtibial prosthetic socket (TPS). After a further screening of the articles, 20 studies were chosen and only one study was done in a developing country. The results showed an increase interest in CAD/CAM application in Transtibial prosthetic socket (TPS) production for both developed and developing countries, yet the technology has not fully utilised in the developing countries. Factors such as resources, accessibility, knowledge-gap and lack of experienced prosthetists remain the major causes of the lack of CAD/CAM system studies. Large-scale trials are required to employ digital fabrication in the developing regions, consequently advancing the production of high-quality CAD-CAM-derived TPS where most prosthetic and orthotics are needed.

Structural Analysis of Product and Computer-Aided Assembly Planning in AssemBL Software Package

2018 ◽  
pp. 11-33
Author(s):  
A. N. Bozhko
Keyword(s):  
Computer Aided Design ◽  
State Of The Art ◽  
Graph Model ◽  
Design System ◽  
Assembly Planning ◽  
Complex Products ◽  
Assembly Sequences ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

Computer-aided design of assembly processes (Computer aided assembly planning, CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. Intensive research on CAAP has been underway since the 1980s. Meanwhile, specialized design systems were created to provide synthesis of assembly plans and product decompositions into assembly units. Such systems as ASPE, RAPID, XAP / 1, FLAPS, Archimedes, PRELEIDES, HAP, etc. can be given, as an example. These experimental developments did not get widespread use in industry, since they are based on the models of products with limited adequacy and require an expert’s active involvement in preparing initial information. The design tools for the state-of-the-art full-featured CAD/CAM systems (Siemens NX, Dassault CATIA and PTC Creo Elements / Pro), which are designed to provide CAAP, mainly take into account the geometric constraints that the design imposes on design solutions. These systems often synthesize technologically incorrect assembly sequences in which known technological heuristics are violated, for example orderliness in accuracy, consistency with the system of dimension chains, etc.An AssemBL software application package has been developed for a structured analysis of products and a synthesis of assembly plans and decompositions. The AssemBL uses a hyper-graph model of a product that correctly describes coherent and sequential assembly operations and processes. In terms of the hyper-graph model, an assembly operation is described as shrinkage of edge, an assembly plan is a sequence of shrinkages that converts a hyper-graph into the point, and a decomposition of product into assembly units is a hyper-graph partition into sub-graphs.The AssemBL solves the problem of minimizing the number of direct checks for geometric solvability when assembling complex products. This task is posed as a plus-sum two-person game of bicoloured brushing of an ordered set. In the paradigm of this model, the brushing operation is to check a certain structured fragment for solvability by collision detection methods. A rational brushing strategy minimizes the number of such checks.The package is integrated into the Siemens NX 10.0 computer-aided design system. This solution allowed us to combine specialized AssemBL tools with a developed toolkit of one of the most powerful and popular integrated CAD/CAM /CAE systems.

scholarly journals Fracture Load of Metal, Zirconia and Polyetheretherketone Posterior CAD-CAM Milled Fixed Partial Denture Frameworks

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 959
Author(s):  
Verónica Rodríguez ◽  
Celia Tobar ◽  
Carlos López-Suárez ◽  
Jesús Peláez ◽  
María J. Suárez
Keyword(s):  
Computer Aided Design ◽  
Testing Machine ◽  
Fracture Load ◽  
Fracture Pattern ◽  
Bending Test ◽  
Weibull Statistics ◽  
Promising Alternative ◽  
Computer Aided ◽  
Cad Cam ◽  
Group 2

The aim of this study was to investigate the load to fracture and fracture pattern of prosthetic frameworks for tooth-supported fixed partial dentures (FPDs) fabricated with different subtractive computer-aided design and computer-aided manufacturing (CAD-CAM) materials. Materials and Methods: Thirty standardized specimens with two abutments were fabricated to receive three-unit posterior FDP frameworks with an intermediate pontic. Specimens were randomly divided into three groups (n = 10 each) according to the material: group 1 (MM)—milled metal; group 2 (L)—zirconia; and group 3 (P)—Polyetheretherketone (PEEK). The specimens were thermo-cycled and subjected to a three-point bending test until fracture using a universal testing machine (cross-head speed: 1 mm/min). Axial compressive loads were applied at the central fossa of the pontics. Data analysis was made using one-way analysis of variance, Tamhane post hoc test, and Weibull statistics (α = 0.05). Results: Significant differences were observed among the groups for the fracture load (p < 0.0001). MM frameworks showed the highest fracture load values. The PEEK group registered higher fracture load values than zirconia samples. The Weibull statistics corroborated these results. The fracture pattern was different among the groups. Conclusions: Milled metal provided the highest fracture load values, followed by PEEK, and zirconia. However, all tested groups demonstrated clinically acceptable fracture load values higher than 1000 N. PEEK might be considered a promising alternative for posterior FPDs.

scholarly journals Evaluation of the Feasibility of NaCaPO4-Blended Zirconia as a New CAD/CAM Material for Dental Restoration

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou
Keyword(s):  
Computer Aided Design ◽  
Optical Microscope ◽  
Dental Restoration ◽  
Numerical Control ◽  
Test Results ◽  
Cnc Machine ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design ◽  
Better Than

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.

BIM based decision-support tool for automating design to fabrication process of freeform lattice space structure

2021 ◽  
pp. 095605992110338
Author(s):  
Saeid Haghir ◽  
Ramtin Haghnazar ◽  
Sara Saghafi Moghaddam ◽  
Danial Keramat ◽  
Mohammad Reza Matini ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Decision Support Tool ◽  
Computational Design ◽  
Space Structure ◽  
Digital Design ◽  
Information Modeling ◽  
Freeform Surfaces ◽  
Geometric Problem ◽  
Support Tool ◽  
Lattice Space

Complex freeform surfaces and structures are increasingly designed and used in the product and building industry due to the advances in mathematics and digital design tools. However, there is still a gap between designing freeform surfaces and fabricating them. The process of preparing freeform surfaces’ shop drawings is complicated, time-consuming, and lacks the mutual understanding among the stakeholders. Computational design and Building Information Modeling (BIM) can serve as a mediator agent for the integration of design goals with the geometric logic of constructability. They can also facilitate creating platforms for designing and evaluating freeform structures. This open-ended qualitative research attempts to develop a systematic methodology for automating the design and construction drafting process of freeform lattice space structure. Solving this complex geometric problem aims to benefit the design for construction and manufacturers and shrink the cost and time of the process. The study employs a 3D computer-aided design (CAD) tool and introduces an algorithm that generates a BIM model. The BIM model contains shop drawings and suggests the specifications of the main elements, such as beams, glass panels, and nodes.

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