Development of novel implant to avoid stress shielding in orthopaedic implants

Overview

This is a joint doctoral project, meaning that upon successful completion of the research, the PhD degree will be awarded by both KU Leuven (BE) and Budapest University of Technology and Economics (HU). The research will be performed under joint supervision of Prof. Kathleen Denis (KU Leuven) and Dr. Gábor Szebényi (BME). The successful candidate will spend 18 months at each of the two institutions.

At BME, the successful applicant will work at the Department of Polymer Engineering of the Faculty of Mechanical Engineering, in a research group focusing on the development of novel metal-polymer implants, test methods and polymeric implant materials. The multidisciplinary team provides an inspiring environment, excellent accredited laboratory and processing laboratory background and insight in different areas of polymer processing and testing.

During the research work the applicant will be able to work together with researchers from the Department of Applied Mechanics of BME, and also researchers from Semmelweis University.

At KU Leuven, the successful applicant will become part of the Smart Instrumentation team of the division of Biomechanical Engineering in the Department of Mechanical Engineering. This team is a growing, multi-disciplinary group dedicated to the development of new surgical instruments and assistive technologies for medical applications, integrating novel sensing and modelling techniques to improve the execution of complex safety-critical tasks in highly unstructured and variable environments such as e.g. the human body.

The team offers a positive and dynamic work environment embedded in a multi-disciplinary network with other research groups in the Department, the broader university and UZ Leuven, the University Hospital, which is also the largest hospital in the country.

This Ph.D. position is offered through the Marie Skłodowska-Curie Actions (MSCA) Doctoral Network 'CUSTOM'. Vacancies for other Ph.D. topics within this network can be found on the project's website.

The CUSTOM project is a Marie Skłodowska-Curie Actions (MSCA) Doctoral Network that unites three core disciplines (design, manufacturing, and testing) towards the development of a next generation of patient-specific shoulder implants. The number of shoulder replacements is projected to increase by 300-400% between 2020 and 2040. With the current technology, 10% of those artificial shoulder implants will fail within the first 10 years of service, mainly due to soft tissue failure, infection, and implant loosening.

CUSTOM focuses on combining (1) computational tools that allow patient-specific design, (2) additive manufacturing to realize the custom, complex designs and structures and their further postprocessing to incorporate multi-functionality, and (3) blended in-silico and experimental testing to reduce the burden on experimental testing for certification. In doing so, CUSTOM can address the major failure mechanisms of current shoulder implants and improve their overall functionality and longevity.

Stress shielding is a key concern in orthopedic implant design, caused by stiffness mismatches between implants and bone, leading to bone resorption and implant loosening. This project addresses the issue by developing stem designs with stiffness closer to that of human bone.

The doctoral candidate will design, analyze and compare orthopedic stem models incorporating porous architectures such as Voronoi or TPMS structures. The project comprises the development of a computational model of humerus and stem (FE), and an experimental set-up for validation of the FE results using micromotion measurements. Multiple design variants will be evaluated with respect to biomechanical performance, manufacturability and applicability in clinical practice.

For validation, micromotion measurements are combined with DIC and/or Fiber Bragg Grating based measurements. The project will be conducted in close collaboration with a clinical partner.

As part of this project you will undertake two three-month research stays (with travel and accommodation costs covered) at world class institutions namely Semmelweis University…