Projects / Programmes
Mechanisms of hip-endoprosthesis loosening
| Code |
Science |
Field |
Subfield |
| 3.03.00 |
Medical sciences |
Neurobiology |
|
| Code |
Science |
Field |
| 3.01 |
Medical and Health Sciences |
Basic medicine |
Hip-endoprostheses, Ti6Al7Nb implant surfaces, aseptic loosening, infection, extracellular vesicles, exosomes, microvesicles, liquid biopsy, laser surface nanostructuring zunajcelični vezikli, eksosomi, mikrovezikli, tekočinska biopsija
Researchers (24)
Organisations (7)
Abstract
Mehanisms of hip-endoprostheses loosening Several specific underlying mechanisms on the surface and subsurface of the Ti6Al7Nb alloy hip endoprostheses that led to the implant’s premature failure either by aseptic loosening or periprosthetic infection and low-grade infection will be investigated. In particular, with recent progress in understanding the connections between aseptic loosening and infection, our proposed project will highlight recent investigations that address both problems together. Part 1 Studies of new and retrieved cementless femoral components of hip-endoprostheses produced from Ti6Al7Nb alloy prematurely failed due to (i) aseptic loosening, (ii) periprosthetic infection and (iii) low-grade infection, will comprise the characterization of the surface properties wettability, roughness, morphology and surface chemistry, microstructure of cross-section samples, surface analysis of the native thin oxide film TiO2 that provides biocompatibility, corrosion resistance, and histological analysis of soft-tissue around the artificial hip We assume that we will be able to confirm two hypothesis on the basisi of the results: 1. The retained corundum particulate debris on the surface and subsurface of the implant after grit blasting release into soft tissue due to constant micro movement of the hip endoprosthesis leading to inflammation and aseptic loosening 2. The retained corundum particles on the surface and subsurface of the implant cause porosity and places for the attachment and colonization of the bacteria, leading to periprostetic infection and premature failure and allowing the distinction of the causes of premature failure, to optimize the surface modification of the implants and achieve optimal osseointegration and prolong longevity of hip-endoprostheses. Part 2 Studies of possible inflammations using extracellular vesicles (EVs) which will be isolated from body fluids (principally from the patients’ blood) and their quantification (e.g., with appropriate biomarkers) reflects the status of the whole organism, since (EVs) alone or through blood cells, blood plasma and endothelium are present in the blood and do not need to perform invasive interventions (e.g., biopsies) to obtain the appropriate material to analyze. We will investigate how the presence of corundum material influences ex-vivo blood-cell vesiculation and will design a clinical study to address blood samples from patients who have experienced prosthesis wear, inflammation or infection after the insertion of the hip endoprosthesis. We will measure the number and size of the particles in blood isolates, and determine their composition (proteome and lipid). Part 3 The laser structuring of the surface of implants from Ti6Al7Nb alloys will be performed. This is an alternative method for modification of the surface to achieve optimum textures for osteointegration without sandblasting with corundum particles or invasive chemical processes. We will investigate whether laser structuring impacts the formation of natural thin oxide layers, which are characteristic for Ti alloys, the texture will also be exposed to anodic oxidation and the mechanism and kinetics of the creation of an optimum oxide layer will be investigated. We will explore non-treated and laser-textured surfaces and analyze the composition of the intermediate layers on the surface of the metallic biocompatible materials with the aim to improve the osteointegration of the bone implant by the application of the model of bone osteosarcoma (MG-63) cells attachment
