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The purpose of this study was to realize finite element simulation in order to dynamically determine the area of the contact, the contact pressure and the strain energy density (identified as a damage function) for three different activities – normal walking, ascending stairs and descending stairs – that could be considered to define the level of the activity of the patient.

The finite element model uses a modern contact mechanism that includes friction between the metallic femoral condyles or femoral head (considered rigid) and the tibial polyethylene insert or acetabular cup (considering a non-linear behaviour).

For all three activities, the finite element analyses were performed, and a damage score was computed. Finally, a cumulative damage score (that accounts for all three activities) was determined, and the areas where the fatigue wear is likely to occur were identified.

A closer look at the distribution of the damage score reveals that the maximum damage is likely to occur not at the contact surface, but in the subsurface.

The purpose of this paper is to investigate by means of finite element analysis (FEA), the effect of polyethylene insert thickness and implant material, under axial loading following TKA.

The 3D geometric model of bone was processed using the CT scan data by MIMICS (3matic Inc.), package. Implant components were 3D scanned and subsequently 3D modeled using ANSYS Spaceclaim and meshed in Hypermesh (Altair Hyperworks). The assembled, meshed bone-implant model was then input to ABAQUS for FE simulations, considering axial loading.

Polyethylene insert thickness was found to have very little or no significance (p>0.05) on the mechanical performance, namely, stress, strain and stress shielding of bone-implant system. Implant material was found to have a very significant effect (p<0.05) on the performance parameters and greatly reduced the high stress zones up to 60 percent on the tibial flange region and periprosthetic region of tibia.

Very few FEA studies have been done considering a full bone with heterogeneous material properties, to save computational time. Moreover, four different polyethylene insert thickness with a metal-backed and all-poly tibial tray was considered as the variables affecting the bone-implant system response, under static axial loading. The authors believe that considering a full bone shall lead to more precise outcomes, in terms of the response of bone-implant system, namely, stress, strains and stress shielding in the periprosthetic region, to loading.

This study aims to design a femoral component with minimum volume and maximum safety coefficient. Total knee prosthesis is a well-established therapy in arthroplasty applications. And in particular, with respect to damaged or weakened cartilage, new prostheses are being manufactured from bio-materials which are compatible with the human body to replace these damages. A new universal method (design method requiring optimum volume and safety [DMROVAS]) was propounded to find the optimum design parameters of tibial component.

The design montage was analyzed via the finite element method (FEM). To ensure the stability of the prosthesis, the maximum stress angle and magnitude of the force on the knee were taken into consideration. In the analysis process, results revealed two different maximum stress areas which were supported by case reports in the literature. Variations of maximum stress, safety factor and weight were revealed by FEM analysis, and ANOVA was used to determine the F force percentage for each of the design parameters.

Optimal design parameter levels were chosen for the individual’s minimum weight. Stress maps were constructed to optimize design choices that enabled further enhancement of the design models. The safety factor variation (SFV) of 5.73 was obtained for the volume of 39,219 mL for a region which had maximum stress. At the same time, for a maximum SFV and at the same time an average weight, values of 37,308 mL and 5.8 for volume and SFV were attained, respectively, using statistical methods.

This proposed optimal design development method is new and one that can be used for many biomechanical products and universal industrial designs.

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.

The purpose of this paper is to use numerical methods and modelling to estimate the effect of a passive, metallic (conducting) implant on eddy currents distribution in a human knee model. There exists a concern among wearers of such implants that they alter electromagnetic field (eddy currents) significantly and there is a need for standardization of that problem.

The numerical model of a human knee has been built on the base of Visual Human Project and electromagnetic field calculations were carried out using Meep FDTD engine. In total, two scenarios have been considered: the knee model with and without a metallic implant. The knee implant model has been prepared as the knee model with overestimated electrical parameters of bone tissues by titanium metal. Alternating eddy current distribution has then been evaluated for both models using FDTD low frequency algorithm.

The highest values of eddy currents occurred on the interface between skin and muscle tissues when the model without an implant is considered. However, when the bone tissues have been replaced with titanium metal, the highest values have occurred in the implant (about 100 times higher than the previous one). This means that an implant can be heated by external electromagnetic fields and that the location of the highest values of eddy currents can be shifted to the proximity of the implant. Moreover, one should realize that in this model the implant is like a knee bone with all anatomical details. It has emerged from this that the implant's shape and size are essential when evaluating its effect on eddy currents distribution.

The interaction of electromagnetic field with implants should be generally further investigated, at least for the presumable worst cases. Such investigation has already been done by some researches but they have been devoted to radio frequencies. The authors believe that the presented research will be helpful in the standardization process, when talking about low frequency electromagnetic field.

The presented methodology can be used in the development of computer aid diagnosis systems. Overestimation of electrical parameters of some parts of the model allows us to predict the distribution of electromagnetic field in the model under investigation very quickly. The results presented in the paper can be used during the standardization process.