Ceramized Articulating Surfaces of Metal-Metal Hip Joint Prosthesis

In this changing global scenario, modification, transplantation, and replacement can be the eternal solution for most of the problems in the medical field. Hence replacement technique finds a very prominent place in medicine as a remedy having closely tied up with biomechanics. One of the most important joints in the human body is the hip joint, the big and complex joint. Many researches were conducted and many are in progress, but most of these works use simplified models with either 2D or 3D approaches. The hip joint is formed by four components like femoral head cortical bone, stem, and neck. In this system we can find orthotropic and isotropic materials working together. The main objective of this research is to develop a three dimensional surface and solid finite element model of the hip joint to predict stresses in its individual components. This model is a geometric non-linear model, which helps us understand its structural mechanical behavior, seeming to suggest with advanced research in the future new hip joint prosthesis, as well as to prove the prosthesis joint interaction before being implanted in the patient. This research explains a complete human hip joint model without cartilaginous tissue, using ANSYS 10.0 Multiphysics Analysis for nine different postures in hip joint using three different materials (CoCr, Ti6Al4V, and UHMWPE) to calculate fatigue life. The result obtained from the analysis of surface model and solid model serve to help in predicting the life cycle, surface characteristics, shear stress in XY plane, stress concentration and areas that are prone to failure. Von Mises stress on the surface of our model facilitates us to equip and design an optimized prosthesis device having unique materials composition , with a highly bio-compatible and durable alloy at a low cost could be produced. In this way, a first important step towards the structural characterization of human hip joint has been developed.

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Laser Surface Texturing of Alumina/Zirconia Composite Ceramics for Potential Use in Hip Joint Prosthesis

Coatings ◽

10.3390/coatings9060369 ◽

2019 ◽

Vol 9 (6) ◽

pp. 369 ◽

Cited By ~ 7

Author(s):

Francesco Baino ◽

Maria Angeles Montealegre ◽

Joaquim Minguella-Canela ◽

Chiara Vitale-Brovarone

Keyword(s):

Hip Joint ◽

Surface Texturing ◽

Scanning Speed ◽

Processing Parameters ◽

Laser Surface Texturing ◽

Joint Prosthesis ◽

Composite Ceramics ◽

Acetabular Cup ◽

Repetition Number ◽

Number Of Cycles

The use of metal shell to fix an acetabular cup to bone in hip joint prosthesis carries some limitations, including restrictions in prosthetic femur ball diameter and in patient’s range of motion. These drawbacks could be ideally overcome by using a monolithic ceramic acetabular cup, but the fixation of such an implant to host bone still remains a challenge. Since porous surfaces are known to promote more bone tissue interlocking compared to smooth materials, in this work the surfaces of sintered alumina/zirconia composite ceramics were treated by a pulsed laser radiation at 1064 nm with a pulse width in the nanosecond range, in order to impart controlled textural patterns. The influence of laser process parameters (e.g., energy per pulse, repetition rate, scanning speed, repetition number, angle of laser beam, and number of cycles) on the roughness and texture orientation was systematically investigated. The obtained surface topographies were inspected by optical and scanning electron microscopy, and the roughness was assessed by contact profilometry. Surface roughness could be modulated in the range of 3 to 30 µm by varying the processing parameters, among which the number of cycles was shown to play a major role. The laser treatment was also successfully adapted and applied to ceramic acetabular cups with a curved profile, thus demonstrating the feasibility of the proposed approach to process real prosthetic components.

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Biomechanical Modeling of Hip Joint Prosthesis

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-64276 ◽

2005 ◽

Author(s):

M. C. Gaspar ◽

A. Mateus ◽

C. Pereira ◽

F. V. Antunes

Keyword(s):

Finite Element ◽

Hip Joint ◽

Laser Scanning ◽

Hip Prosthesis ◽

Element Model ◽

Geometrical Model ◽

Elastic Behavior ◽

Joint Prosthesis ◽

Element Analysis

In this work a Bombelli cementless isoelastic RM total hip prosthesis was considered. It was implanted over a course of 14 years on the patient and studied subsequently to its chirurgical replacement. Computed Tomography, radiographies and 3-D laser scanning were used to assess the prosthesis geometry, while the original femur anatomy was modeled based on 2-D radiographies taken at different stages of the in-vivo implant of the prosthesis. A finite element model was developed, based on the generated 3-D geometrical model, considering a linear elastic behavior and typical loading conditions. This analysis allowed determining stress and strain fields throughout bone-prosthesis contact surface and critical areas in terms of micromovements. The developed procedure, consisting of 3-D scanning, generation of geometrical 3-D models and finite element analysis, results in a powerful tool to follow-up and predict failure mechanisms in hip joint prosthesis.

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