iSMART (Instrumented Sensor Module for Arthroplasty Treatment)

This project aims develop a self-contained instrumented module capable of measuring force, motion, and temperature which can be incorporated within the polyethylene components of a TKR.
The proposed PhD project will concentrate itself on the first research challenge described above: "the miniaturisation of the components required so as to not compromise the integrity of the polyethylene insert over its lifetime as an implant".
The candidate will work alongside a post-doctoral engineer (who will be concentrate on the developing the sensor module) to develop a strategy for incorporating the iSmart sensor module into the polyethylene component of a TKR while minimising and ideally negating its impact on structural integrity and wear of the insert.
Below we describe how we envision the overall structure of the PhD candidates approach.
Project activity breakdown:
It is expected that the student's PhD will work around these themes as part of a design team within the overall aim of developing and testing a prototype iSMART device.
1. Prototype structural design
2. Prototype manufacture
3. Failure & wear testing
Description of work:
1: Prototype design
The sensor will need to undergo optimisation with respect to its size and placement within the implant. The device will have 9 components in total; arranged in an optimal position with an efficient housing so as to not influence the integrity or function of the implant. Custom components will then be manufactured and assembled to ensure its functionality. CAD modelling software will be used to design the sensor & antennae shapes. In the initial design stages of prototype design the aim is to explore positioning of the component within the implant using finite element modelling. This will help determine the optimal position of components as well as the potential space available to work with within the implant.
2: Prototype manufacture
Having modelled the optimal position and designed a prototype insert. Medacta - our industry partner will manufacture the instrumented polyethylene inserts which will be examined for polyethylene integrity and quality. Implant surface integrity will be tested using optical profiling. The accuracy of iSMART positioning will be confirmed using x-rays and micro CT.
3: Failure & wear testing
It is essential that the incorporation of the iSMART does not compromise the integrity of the insert under physiological conditions. Failure testing will determine the point at which the bearing fails in comparison to a standard bearing and wear testing will allow us to determine if the iSMART equipped insert meets longevity standards.
The iSMART equipped implant will need testing to the point of failure and compare the point of failure to that of a conventional bearing. This testing will be performed using a servo-hydraulic testing rig to apply a compressive and shear forces to both normal and sensor equipped bearings till failure. The required force for each will be compared to determine the effect of incorporating the sensor in the bearing.
Wear properties of the iSMART equipped implant will be tested to industry standards (ISO 14708-1:2014) using knee wear simulators to ensure that regulatory standards are met.
Facilities / Support:
The programme of work will be based in part at iMBE and in part at University of Leeds main [main campus (Worsley building) or Chapel Allerton Hospital]. Many if not all of the facilities required for the continuation of this project are readily available in house.
The student will be supported by a post-doc (with PhD in mechanical engineering, a consultant colleague who has developed the previous prototype, clinicians (orthopaedic surgeon based in Leeds) and a named supervisor from iMBE. In addition, support needed for manufacturing and testing the prototype insert will be available from Medacta international.

Regenerative Medicine been defined as "an interdisciplinary approach, spanning tissue
engineering, stem cell biology, gene therapy, cellular therapeutics, biomaterials (scaffolds and matrices),nanoscience, bioengineering and chemical biology that seeks to repair or replace damaged or diseased human cells or tissues to restore normal function, (UK Strategy for Regenerative Medicine). CDT TERM will focus on acellular therapies, scaffolds,autologous cells and regenerative devices, which can be delivered to patients as class three device interventions, thus reducing the time and cost of translation and which provide an opportunity to deliver economic growth and benefits to health in the next decade. The primary beneficiaries of CDT TERM are patients, the health service, UK industry, as well as the academic community and the students themselves. Recognising that the impact and benefit from CDT TERM will arise in the future, the statements describing impact below are supported by evidence of actual impact from our existing research and training.

Patients will benefit from regenerative interventions, which address unmet clinical needs, have improved safety and reliability, have been stratified to meet patients needs and manufactured in a cost effective manner. An example of impact arising from previous students work is a new acellular scaffold for young adult heart valve repair, which has demonstrated improved clinical outcomes at five years.

The Health Service will benefit from collaborations on research, development and evaluation of technologies, through existing partnerships with National Health Service Blood and Transplant NHSBT and the Leeds Biomedical Musculoskeletal Research Unit LMBRU. NHSBT will benefit through collaborative projects, through technology transfer, through enhancement of manufacturing processes, through pre-clinical evaluation of products and supply of trained personnel. We currently collaborate on heart valves, skin, ligaments and arteries, have licensed patents on acellular bioprocesses, and support product and process developments with pre-clinical testing and simulation. LMBRU and NHS clinicians will benefits from our collaborative research and training environment and access to our research expertise, facilities and students. Existing collaborative projects include, delivery devices for minimally manipulated stem cells and applied imaging for early OA.

Industry will benefit from supply of highly trained multidisciplinary engineers and scientists, from collaborative research and development projects, from creation and translation of IP, creation of spinout companies and through access to unique equipment, facilities and expertise. We have demonstrated: successful spin outs in form of Tissue Regenix and Credentis; successful commercialisation of a novel biological scaffolds for vascular patch repair; sustainable long term R and D and successful licensing of technology with DePuy; collaborative research with Invibio, partnering with Simulation Solutions to develop new pre-clinical simulation systems, which been adopted by regulatory agencies such as China FDA. Our graduates and researchers are employed by our industry partners.

The academic community will benefit through collaborative research and access to our facilities. We have funded collaborations with over 30 academic institutions in UK and internationally. The CDT TERM will support these collaborations and the academic partners will support student research and training. The CDT students will benefit from enhanced integrated multidisciplinary training and research, a cohort experience focused on research innovation and translation, access to our research partners, industry and clinicians. Feedback from existing students has identified the benefit of the multidisciplinary experience, the depth and breadth of excellence in our research base, the outstanding facilities and the added value of the cohort training.