Development Of A Wirelessly Powered Smart Implant To Monitor Spinal Fusion

Download or read book Development of a Wirelessly Powered Smart Implant to Monitor Spinal Fusion written by Nicole (Negar) Zoka and published by The University of Auckland. This book was released on 2021-01-01 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lumbar spinal fusion surgery is performed on patients in whom non-operative treatments have failed to relieve chronic lower back pain (LBP) and restore functionality. The procedure involves inserting titanium alloy rods adjacent to two or more vertebrae on each side of the spine to support spinal fusion. Currently, clinicians rely upon periodic x-ray radiographic images to track fusion progress and determine whether patients can resume normal activities or to assess if the fusion has failed. However, the reliability of imaging evaluation techniques is questionable and leads to either very conservative (and prolonged) restrictions on activity or additional exploratory surgeries. The definitive criteria for a successful fusion remain ambiguous, and determining the progress of spinal fusion remains a challenge for orthopaedic surgeons and clinicians. Observing strain variations on a spinal fusion rod post-implantation has been demonstrated to correlate with changes in bony mass stiffness as fusion progresses, indicating the state of fusion. The challenge with strain measurements relates to having a reliable implant which aligns with existing clinical workflows and provides new data on the state of healing. If the existing titanium alloy rod could be made "smart", i.e. the strain measurement capabilities are embedded into the rod, then the existing clinical, surgical workflow could be maintained. This research focuses on the design and development of a smart spinal fusion implant with the potential to measure strain without complication in the surgical procedure. To meet this aim, two key research questions were addressed. First, a fully implantable wireless spinal rod was developed to support animal trials of spinal fusion. The implant was constructed by mounting a semiconductor strain gauge sensor into a housing machined into a custom spinal rod. A miniaturised electronic module was developed to measure the strain and transmit the data to an external wireless receiver. The module consisted of a strain gauge signal conditioning which was controlled by a microcontroller, and a custom wireless power and data transfer application-specific integrated circuit (ASIC) developed previously at the Auckland Bioengineering Institute (ABI). The electronics module was mounted into the housing, and a printed circuit board (PCB) coil was placed on top of it. This was sealed under a liquid crystal polymer (LCP) lid. Wireless power was transferred to the implant from an external coil at 6.78MHz for 980ms, over which 10 samples of strain were measured. The data was then transmitted using phase-shift keying at a data rate of 678kbps at 6.78MHz. Data was received at an external coil, demodulated and logged to a computer with a measurement cycle taking one second. The implant was characterised on a test rig, and it was confirmed that the 24-bit strain values could be wirelessly measured using the smart spinal implant designed to achieve 1με resolution. This showed that the device was ready for animal trials to quantify strain as fusion occurs in a sheep model. Second, to make the implant clinically relevant, it would be preferable to replace the LCP lid with titanium. LCP is an appropriate seal for animal trials with a lifespan of around several months before water permeates through it, and the device becomes unreliable. Titanium can be welded to the rod to achieve a hermetic seal (gas-tight) with a lifespan of many years, which leads to a smaller device and eases reliable manufacturing as welding is possible. However, this would require transferring inductive power through the conductive titanium lid, which has not been achieved in a spinal implant. Thus, inductive power transfer through metal sheets was investigated via a combination of numerical and experimental tests. A simple test set-up based on hand-wound, cylindrical 10-turn primary (inner radius of 30mm) and 10-turn secondary coils (inner radius of 5mm) was created into which metal sheets could be introduced to allow study their impact on wireless power transfer. The equivalent 2D axisymmetric FEM models were developed to analyse inductive link principles and validate experimental studies. The hand-wound coils were also used to investigate the impact of a titanium enclosure on IWPT system parameters through both simulations and experiments. The simulation results matched experimental results reasonably well, validating the approach; thus, in the future, the validated FEM simulations could be used to investigate power transfer to a miniaturised titanium-packaged smart spinal fusion implant. The impact of the titanium spinal fusion implant, consisting of a titanium spinal rod, housing, and lid, on an IWPT system and an optimum frequency for maximum power transfer was determined. The maximum transferred power was dependent on the titanium alloy, lid thickness, implant size, implant coil location, frequency of power transmission, magnitude of the primary field, and primary and secondary coils dimensions and configurations. FEM simulation results revealed that a maximum power of 1.84mW, at 1A primary current and an operating frequency of approximately 400kHz, could be transferred through a 110μm-thick Grade-5 titanium lid used to seal a 5.5mm-thick, 50mm-long Grade-5 titanium rod, and 0.5m-thick, Grade-5 housing with an internal volume of 18 x 8 x 5mm (L x W x H) for this spinal fusion application. The maximum link potential of 0.035 at 199kHz could be achieved for the same set-up. These results indicated that an acceptable amount of power could be transferred through titanium to power the implanted electronics, supporting the future development of titanium packaged smart spinal fusion rods. This research supports the hypothesis that it is feasible to construct a smart spinal fusion implant that includes the function of measuring strain, can ultimately be employed in clinical practices of spinal fusion, detection of the onset of fusion, non-union or other complications, determination of the efficiency of various bone treatments, and the design of rehabilitation protocols.

Download or read book Calcium-Based Materials written by S.S. Nanda and published by CRC Press. This book was released on 2024-05-15 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calcium-based natural minerals are important for a wide range of applications. Though these materials are available in nature, researchers are working toward developing them in the laboratory. Calcium-Based Materials: Processing, Characterization, and Applications introduces the possibility of designing these materials for particular applications. Introduces a variety of calcium-based materials and discusses synthesis, growth, and stability Provides in-depth coverage of calcium carbonate Discusses applications of calcium-based minerals in different fields Includes details on synchrotron X-ray tools for case minerals This comprehensive text is aimed at researchers in materials science, engineering, and bioengineering.

Download or read book PHealth 2012 written by B. Blobel and published by IOS Press. This book was released on 2012-06-12 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microsystems, smart textiles, telemedicine, smart implants and sensor-controlled medical devices have become important enablers for monitoring and treatment in both inpatient and outpatient care. Indeed, micro and nano technologies have tremendous potential for increasing access to care whilst managing healthcare costs. They are set to be at the heart of evolutionary and revolutionary changes in healthcare, and are crucial, not only for the future of medicine, but also for the improvement of health care and welfare processes today and tomorrow. This book presents the proceedings of the 2012 pHealth conference, held in Porto, Portugal, in June 2012. The pHealth conference has emerged as the leading international meeting on wearable micro and nano technologies for personalized medicine, attracting scientists from various disciplines, clinicians, as well as policy makers from the healthcare industry, hospital administration and allied professionals. The book includes keynotes, invited speeches and selected submitted contributions. The areas covered include: the pHealth approach, new approaches to diagnosis and therapy, monitoring special diseases, system architecture, design and implementation, wearable sensor systems, smartphone applications and ambient assisted living. Over the years, pHealth has given visibility to the tremendous potential of micro and nano technologies, not only for the future of medicine, but also for the improvement of healthcare processes today. This book will be of interest to all those involved with the provision of health and welfare services, and also to companies engaged in the development of micro and nano technologies.

Download or read book Encyclopedia of Health Communication written by Teresa L. Thompson and published by SAGE Publications. This book was released on 2014-04-18 with total page 1663 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the dynamics of interpersonal communication between health professionals and clients to global command-and-control during public health emergencies that cross international borders, the field of health communication bridges many disciplines and involves efforts from the micro to the macro. It involves navigating personal, cultural, and political complexities and an ability to distill complex technical science into quickly and easily understood terms for ready distribution by the mass media--or to an individual patient or to the parent of an ailing child. Despite an abundance of textbooks, specialized monographs, and academic handbooks, this is the first encyclopedic reference work in this area, covering the breadth of theory and research on health communication, as well as their practical application. Features: Nearly 600 original articles are organized A-to-Z within a three-volume set to provide comprehensive coverage of this exciting field, including such topics as theories and research traditions; evaluation and assessment; cultural complexities; high risk and special populations; message design and campaigns; provider/patient interaction issues; media issues; and more. All articles were specifically commissioned for this work, signed and authored by key figures in the field, and conclude with cross reference links and suggestions for further reading. Appendices include a Resource Guide with annotated lists of classic books and articles, journals, associations, and web sites; a Glossary of specialized terms; and a Chronology offering an overview and history of the field. A thematic Reader’s Guide groups related articles by broad topic areas as one handy search feature on the e-Reference platform, which also includes a comprehensive index of search terms. This A-to-Z three-volume reference is available in both print and online formats and is a must-have for libraries and researchers who seek comprehensive coverage of the theory, research, and applications of health communication.

Download or read book Popular Science written by and published by . This book was released on 2005-09 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Popular Science gives our readers the information and tools to improve their technology and their world. The core belief that Popular Science and our readers share: The future is going to be better, and science and technology are the driving forces that will help make it better.

Download or read book Popular Science written by and published by . This book was released on 2004-12 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: Popular Science gives our readers the information and tools to improve their technology and their world. The core belief that Popular Science and our readers share: The future is going to be better, and science and technology are the driving forces that will help make it better.

Download or read book Popular Science written by and published by . This book was released on 2003-12 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Popular Science gives our readers the information and tools to improve their technology and their world. The core belief that Popular Science and our readers share: The future is going to be better, and science and technology are the driving forces that will help make it better.