Additive manufacturing of fracture fixation implants: Design, material characterization, biomechanical modeling and experimentation
64
Citation
81
Reference
10
Related Paper
Citation Trend
Abstract:
Recent advancements in additive manufacturing (AM) have motivated researchers to consider this fabrication technique as a solution for challenges in patient-specific orthopaedic needs. Although there is an increasing trend in the applications of AM in medical fields, there is a critical need to understand the biomechanical performance of AM implants. In particular, design opportunities, anisotropic material properties and resulting stability of AM implant constructs for large bone defects such as osteosarcoma, comminuted fractures and infections are unexplored. This study aims to evaluate metal AM for complex fracture fixation using both computational and experimental methods. In addition, this research highlights the role of AM in the entire workflow to fabricate metal AM fixation plates for treatment of comminuted proximal humerus fractures. A new AM-centric patient-specific implant design for reducing common postoperative complications such as varus collapse and screw cutout is investigated. Biocompatible 316L stainless steel specimens processed in laser-powder bed fusion (L-PBF) is subjected to tensile testing and post-hoc microhardness to obtain orthotropic material properties of the AM implants. Subsequently, risk of screw cut-out is evaluated using finite element modelling (FEM) of AM implant-bone constructs. Parallel experiments included synthetic bones that are evaluated using a 3D motion capture system. The biomechanical tests are analyzed to quantify the medial fracture gap displacement among study groups subject to different loading conditions. The outcomes of this study suggest that the proposed AM-centric fixation plate design reduces average varus collapse (i.e. medial fracture gap displacement) by 47.2 % and risk of screw cut-out by 14.6 % when compared to the conventional plate design. Findings from this study can be extended to other patient anatomy, loading conditions, and AM processes.Keywords:
Orthotropic material
Bone fracture
Biomechanics
Orthotropic material
Cite
Citations (241)
This paper discusses the limitations of the existing finite element beam models for the analysis of orthotropic laminate beam analysis. These limitations are illustrated by comparing the existing models with a finite element model which has recently been developed by the author. This new model overcomes some of the existing limitations and is applicable to thin, laminated beam cross sections which are either open or closed. A simple numerical example is given and discussed comparing the existing theories with the results from the new model. The main limitations of the existing finite element models fall into two categories. The first of these is the problem of accurately modeling stresses in laminated configurations, especially if the orthotropic properties vary from layer to layer. The second difficulty is to model accurately the interaction between various deformations such as, for example, shear and normal strains.
Orthotropic material
Cite
Citations (3)
To reduce computational effort of finite element (FE) calculations a corrugated sheet is replaced with an orthotropic plate. Analytical expressions for the mechanical properties are studied and compared to finite Element calculations in extension, free vibration, and buckling. Good similarity is shown in the stiffened and transverse direction of the corrugated sheet; however, the orthotropic models do not give an accurate twisting behavior. The stiffened direction of the corrugated sheet best matches the analytical expressions. Keeping in mind the presented limitation, the orthotropic model presented herein can be used to drastically reduce the number of elements needed when modelling corrugated sheet with finite elements.
Orthotropic material
Similarity (geometry)
Cite
Citations (23)
This paper describes the static and dynamic analysis of thin isotropic and orthotropic CCCC plates. Two methods of analyses were carried out and compared. One is the theoretical analysis, the second is the finite element analysis with the conventional finite element modeling approach. The theoretical analysis was divided into stress, deflection, and frequencies calculations. The analysis was carried out using the classical thin plate theory. For the finite element analysis, the analyses were performed using the ANSYS finite element software. The first Five natural frequencies were obtained for the plates. For all these methods, the theoretical and numerical analyses are to be compared.
Orthotropic material
Natural frequency
Cite
Citations (3)
Abstract The two‐scale simulation of a linear‐elastic orthotropic disc with a central crack under mode‐I loading may be used to verify the extended finite element method implementation of orthotropic enrichment functions into finite element codes such as FEAP. The stress distribution on the finer scale is simultaneously resolved by the high fidelity generalized method of cells called at each integration point of the macro elements. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Orthotropic material
Macro
High fidelity
Mode (computer interface)
Macroscopic scale
Cite
Citations (0)
Beagle
Biomechanics
Cite
Citations (63)
Based on a constructional orthotropic steel deck,multiple finite element models with different element constitution are analyzed.Stress amplitude of structural members is obtained.By comparative analysis,the finite element analysis of adopting the ribbed plate element simulating the orthotropic deck is more accurate,simple and helpful,which can be provided for references.
Orthotropic material
Cite
Citations (0)
Orthotropic material
Delamination
Tension (geology)
Cite
Citations (14)