The recent innovation in additive manufacturing technologies has made improvements to address personalised medicine. From this perspective, this dissertation discusses the relevance of metal 3D printing (3DP) for customised implant manufacturing, potentially meeting the unmet clinical needs for personalised treatments in developing Asian countries. Additionally, the dissertation includes a relevant review of literature on morphometric analysis based on gender and different ethnicities concerning the biomechanical aspects of the hip bone, and gait pattern essential for implant design. At the peak of the literature review, the environmental impact of metal manufacturing methods for orthopaedic implants is discussed. An effort has been made to identify existing challenges concerning scientific, technological and economic aspects that need to be addressed. Finite element analysis (FEA) is one of the most versatile methods to scrutinise complex geometries and non-homogeneous material properties for biomechanical modelling. One of the prime advantages of FEA in my thesis is that FEA accommodates structural optimisation of femoral implant design by removing excess material through the incorporation of central hollowness and exercising weight distribution throughout the porous implant design. The impact of two femoral stem designs, solid implant and centrally hollow (internal hollowness), on the stiffness of the bone, is studied by conducting an FEA analysis. This FEA model also studied the critical role of subject weights and bone conditions in the two implant designs. The principal motivation to introduce central hollowness is to check for a reduction in implant stiffness and observe a stress/strain profile closer to natural bone. The results from this study are likely to achieve femoral stem designs for better physiological outcomes and improve the quality of patients undergoing THR. Despite the advanced growth of laser-powder bed fusion in recent years, major challenges include inconsistent part properties and porosity development. For a range of printing parameters that give maximum volumetric energy density, findings for microhardness, texture and anisotropy of 3D printed Ti6Al4V using one of the smallest LPBF printers (by build volume) on the market are revealed.
Patient Specific Metallic Implants for Personalised Medicines
Johl, R. (Author). 1 Aug 2023
Student thesis: Master of Philosophy