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This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

An anisotropic modelling of hollow porous cylinders under harmonic axial loading is proposed to simulate the in vivo behavior of structural elements of cortical bone called osteons. The peripheral surface of the medium is supposed to be impermeable, except on possible existing cracks. Numerical tests are performed by analytical and finite element methods based on the Biot poroelastic theory. The influence of microcracks on the fluid flow is numerically investigated. The findings show that the existence of peripheral cracks directly modifies the stimulation of the mechano‐sensitive network of the bone. Thus, this study attempts to propose a likely mechanism by which bone can sense changes of the surrounding mechanical environment.

A complete analysis for illustrating the various factors responsible for electrical stimulation can provide insight about some interaction effects relationship. The paper aims to evaluate the electric field and current density distributions inside the various tissues of two simplified models of arm and spine, when a external electric signal is applied using external electrodes in contact with the skin.

Electrical stimulation is a widely used clinical method in which fracture non‐unions are treated with low‐level electric fields and currents in order to stimulate fracture repair. The physical methods for bone growth stimulation discussed in this paper is referred to technique with capacitively coupled electric fields (CCEF) at the fracture site.

A series of experiments demonstrated that bone is piezoelectric, electro stimulation is often used to promote and expedite healing. The results of numeric simulation improve the understanding of healing mechanism and bone rebuilding.

Electric and magnetic fields can influence biological functions. The algorithm should be useful in calculating the response of biological materials subject to excitation including modelling and electrical stimulation.

It used to be thought that a humped back and an increased likelihood of fracturing a wrist or hip were simply associated with getting old but it is now known that these painful problems are related to bone weakness that occurs independently of ageing. One in four women over 60 and one in forty men suffer pain and disability from fractures because their bones have become too porous and brittle.1 This disease is called osteoporosis. It is on the increase and has been referred to, by the National Osteoporosis Society and others, as the ‘silent epidemic’.

A set of algorithms has been developed and evaluated for 3D and 21/2D rapid prototyping replication of 3D reconstructions of cancellous bone samples. The algorithms replicate a voxel map without any loss of fidelity, so as to increase the validity of the comparison of mechanical tests on the 3D reconstructed models with those predicted by finite element analyses. The evaluation is both in terms of algorithmic complexity and the resultant data set size. The former determines the feasibility of the conversion process, whereas the latter the potential success of the manufacturing process. The algorithms and their implementation in PC software is presented.

Fruits and vegetables (FVs) are a good source of substances that contributed to bone health. However, the relation of FVs consumption with inflammation and bone biomarkers is inconsistent. Thus, this paper aims to assess the association of FVs intake with inflammation and bone biomarkers in older adults.

This cross-sectional study was performed on 178 older adults in Tehran, with a mean age of 67.04. Biochemical measurements including serum osteocalcin, high sensitivity c-reactive protein, 25-hydroxyvitamin D 25(OH) D, parathormone and urine terminal telopeptide of Type I collagen (u-CTx) was done. The intake of FVs was calculated using a validated quantitative food frequency questionnaire.

Pearson correlation coefficients showed a positive relation between serum osteocalcin and total vegetables (r = 0.167, p = 0.026), juices group (r = 0.155, p = 0.035), starchy vegetables (r = 0.205, p = 0.006) and other vegetable group (r = 0.161, p = 0.032) even after controlling of potential confounders. Analysis of covariance showed that total vegetable were significantly associated with serum osteocalcin (p = 0.041) and PTH levels (p = 0.028). Additionally, no evidence of a significant relationship between total fruit intake and test variables was observed. However, subgroup analyses demonstrated a significant association between citrus fruits and serum 25(OH) D (p = 0.017). A significant relation between starchy vegetable and urine CTx-I was reported (p = 0.016). Moreover, other vegetable subgroup was strongly associated with serum osteocalcin (p = 0.003).

The results of this paper may provide insight for clinical interventions and also important to make policy for prevention or easing bone disorders and general inflammation related to fruit and vegetable intake.

The purpose of this paper is to investigate the use of medical‐grade polymethylmethacrylate (PMMA) in fused deposition modeling (FDM) to fabricate porous customized freeform structures for several applications including craniofacial reconstruction and orthopaedic spacers. It also aims to examine the effects of different fabrication conditions on porosity and mechanical properties of PMMA samples.

The building parameters and procedures to properly and consistently extrude PMMA filament in FDM for building 3D structures were determined. Two experiments were performed that examined the effects of different fabrication conditions, including tip wipe frequency, layer orientation, and air gap (AG) (or distance between filament edges) on the mechanical properties and porosity of the fabricated structures. The samples were characterized through optical micrographs, and measurements of weight and dimensions of the samples were used to calculate porosity. The yield strength, strain, and modulus of elasticity of the samples were determined through compressive testing.

Results show that both the tip wipe frequency (one wipe every layer or one wipe every ten layers) and layer orientation (transverse or axial with respect to the applied compressive load) used to fabricate the scaffolds have effects on the mechanical properties and resulting porosity. The samples fabricate in the transverse orientation with the high tip wipe frequency have a larger compressive strength and modulus than the lower tip wipe frequency samples (compressive strength: 16±0.97 vs 13±0.71 MPa, modulus: 370±14 vs 313±29 MPa, for the high vs low tip wipe frequency, respectively). Also, the samples fabricated in the transverse orientation have a larger compressive strength and modulus than the ones fabricated in the axial orientation (compressive strength: 16±0.97 vs 13±0.83 MPa, modulus: 370±14 vs 281±22 MPa; for samples fabricated with one tip wipe per layer in the transverse and axial orientations, respectively). In general, the stiffness and yield strength decreased when the porosity increased (compressive strength: 12±0.71 to 7±0.95 MPa, Modulus: 248±10 to 165±16 MPa, for samples with a porosity ranging from 55 to 70 percent). As a demonstration, FDM is successfully used to fabricate patient‐specific, 3D PMMA implants with varying densities, including cranial defect repair and femur models.

This paper demonstrates that customized, 3D, biocompatible PMMA structures with varying porosities can be designed and directly fabricated using FDM. By enabling the use of PMMA in FDM, medical implants such as custom craniofacial implants can be directly fabricated from medical imaging data improving the current state of PMMA use in medicine.

Optimization techniques can be used to design geometrically complex components with a wide variety of optimization criteria. However, such components have been very difficult and costly to produce. Layered fabrication technologies such as electron beam melting (EBM) open up new possibilities though. This paper seeks to investigate the integration of structural optimization and direct metal fabrication process.

Mesh structures were designed, and optimization problems were defined to improve structural performance. Finite element analysis code in conjunction with nonlinear optimization routines were used in MATLAB. Element data were extracted from an STL‐file, and output structures from the optimization routine were manufactured using an EBM machine. Original and optimized structures were tested and compared.

There were discrepancies between the performance of the theoretical structures and the physical EBM structures due to the layered fabrication approach. A scaling factor was developed to account for the effect of layering on the material properties.

Structural optimization can be used to improve the performance of a design, and direct fabrication technologies can be used to realise these structures. However, designers must realize that fabricated structures are not identical to idealized CAD structures, hence material properties much be adjusted accordingly.

Integration of structural optimization and direct metal fabrication was reported in the paper. It shows the process from design through manufacturing with integrated analysis.

The purpose of this paper is to develop a heuristic method for topology optimization of a continuum with bi-modulus material which is frequently occurred in practical engineering.

The essentials of this model are as follows: First, the original bi-modulus is replaced with two isotropic materials to simplify structural analysis. Second, the stress filed is adopted to calculate the effective strain energy densities (SED) of elements. Third, a floating reference interval of SED is defined and updated by active constraint. Fourth, the elastic modulus of an element is updated according to its principal stresses. Final, the design variables are updated by comparing the local effective SEDs and the current reference interval of SED.

Numerical examples show that the ratio between the tension modulus and the compression modulus of the bi-modulus material in a structure has a significant effect on the final topology design, which is different from that in the same structure with isotropic material. In the optimal structure, it can be found that the material points with the higher modulus are reserved as much as possible. When the ratio is far more than unity, the material can be considered as tension-only material. If the ratio is far less than unity, the material can be considered as compression-only material. As a result, the topology optimization of continuum structures with tension-only or compression-only materials can also be solved by the proposed method.

The value of this paper is twofold: the bi-modulus material layout optimization in a continuum can be solved by the method proposed in this paper, and the layout difference between the structure with bi-modulus material and the same structure but with isotropic material shows that traditional topology optimization result could not be suitable for a real bi-modulus layout design project.

The purpose of this paper is to investigate the wave propagation of wave in an infinite poroelastic cylindrical bone. The dynamic behavior of a wet long bone that has been modeled as a piezoelectric hollow cylinder of crystal class 6 is investigated.

An exact closed form solution is presented by employing an analytical procedure. The frequency equation for poroelastic bone is obtained when the boundaries are stress free and is examined numerically.

The study of wave propagation over a continuous medium is of practical importance in the field of engineering, medicine and bio-engineering. Application of the poroelastic materials in medicinal fields such as orthopedics, dental and cardiovascular is well known. In orthopedics, wave propagation over bone is used in monitoring the rate of fracture healing. There are two types of osseous tissue, such as cancellous or trabecular and compact or cortical bone, which are of different materials, with respect to their mechanical behavior.

The frequencies are calculated for poroelastic bone for various values for different values of rotation, angular velocity and density. In wet bone little velocity dispersion was observed, in contrast to the results of earlier studies on wet bone. Large values of attenuation were observed. Such a model would in particular be useful in large-scale parametric studies of bone mechanical response.