This seminar is a hybrid event taking place in lecture theatres U1202 and U1203 and online. You can choose to order an in-person ticket or a virtual attendance ticket when registering to attend.
For those attending in person, refreshments will be served immediately after this seminar outside rooms U1202 and U1203.
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Speaker:
Dr John Costi, Associate Professor, College of Science and Engineering, Flinders University.
Location:
U1202 and U1203, Sir Michael Uren Hub, Imperial College London White City campus and online via Microsoft Teams.
Title:
A multiaxial and multiscale assessment of lower back injury mechanisms
Abstract:
Chronic low back pain (LBP) is a crippling condition that affects the quality of life and significantly burdens the health care system and the workforce. The mechanisms of LBP are poorly understood; however, it is well known that the loss of intervertebral disc height due to degeneration is a common cause of low back and referred pain.
Poor vascularity and slow disc repair render it susceptible to circumferential tears, which are present from the teenage years and arise from the delamination of adjacent lamellae within the annulus fibrosus. These tears are associated with disc degeneration and likely increase the risk of herniation (aka ‘a slipped disc’) via either a single overload or repetitive lifting events.
The major underlying microstructural components contributing to these tears are collagen and elastin, which are found within the extracellular matrix in the annulus fibrosus. However, there is a limited understanding of how degeneration affects the mechanical properties of collagen type I individual fibre bundles (microscale) and isolated fibrils (nanoscale). Furthermore, there are significant gaps with respect to both the ultrastructural organisation and mechanical properties of the elastic fibre network between adjacent lamellae (i.e., interlamellar matrix: ILM). A new understanding of the role of the ILM during progressive loading to disc herniation and internal disc deformations during repetitive simulated lifting motions is required.
This presentation will discuss my research program on the multiscale assessment of the effects of disc degeneration and herniation. A sophisticated multiaxial hexapod robot was developed to simulate lifting loads on cadaver lumbar segments and measure internal disc deformations to determine a lifting injury threshold. Current research that extends on these findings will also be discussed.
Speaker Biography:
John is a Mechanical Engineer who completed his PhD in intervertebral disc biomechanics in 2004 at Flinders University. In 2005-2006 he undertook a postdoctoral fellowship at the University of Vermont in Burlington, Vermont, USA. In 2009, he joined The College of Science and Engineering, Flinders University, in his current position as an Academic staff member, where he teaches Solid Mechanics and Biomechanics. From 2009-2011 he led a collaborative team to design and develop a novel, award-winning, six-degree-of-freedom hexapod robot for the three-dimensional loading of biological joints and tissues. His research program aims to understand the fundamental multiscale properties of ordinary, degenerated, and injured discs and their failure mechanisms and to develop medical devices to treat these problems. He has been working in the field of orthopaedic biomechanics research for almost 30 years.
He holds several leadership roles: Vice President and President-Elect of the Spine Society of Australia, Head of the Biomechanics and Implants Laboratory and Director of Flinders Surgical Lab. John is a Fellow of the Institution of Engineers Australia (Biomedical and Mechanical Engineering Colleges, 2015-), a Fellow of International Orthopaedic Research of the International Combined Orthopaedic Research Societies (2019-), and was a recipient of the Spine Society of Australia Spinal Research Award (2017, 2019).