Day 2 :
Australian National University, Australia
Time : 10:00 - 10:30
Rachel W Li has completed her PhD in Australia and gained her Postdoctoral experiences in Molecular Pharmacology focusing on immune regulation of metabolic diseases at the University of Hawaii, USA. She returned to Australia joining the Trauma and Orthopaedic Research Unit (TORU) at the Australian National University Medical School and has established TORU Laboratory. She is currently leading her team with a focus on osteoimmunology, biomaterials and 3D printing for orthopedic implants.
Statement of the Problem: Heparanase is the only known mammalian endoglycosidase capable of degrading the heparan sulfate (HS) glycosaminoglycan, both in extracellular space and within the cell. HS is reported to control inflammatory responses at multiple levels, including the sequestration of cytokines/chemokines in the extracellular space, the modulation of the leukocyte interaction with the endothelium and ECM, and the initiation of innate immune responses. We have reported heparanase expression in synovium of rheumatoid arthritis (RA) patients and this new finding may offer a new insight of the potential regulatory role of heparanase in the disease activity of RA. However, the precise mode of action by heparanase in inflammatory reactions of RA remains largely unknown.
Aim: The purpose of this study is examine the heparanase activity, its expression and correlation with the inflammatory mediatory and angiogenic gene expression in plasma and synovium of RA patients, with an ultimate goal of developing heparanase as a potential predictor of RA progression and a new therapeutic target.
Methodology & Theoretical Orientation: HPSE activity was detected using ELISA. HPSE mRNA expression and osteogenic gene expression were measured by RT-qPCR Array assay.
Findings: Heparanase activity and its expression in synovial fluid and synovial tissue of RA patients were significantly increased and an increase of the heparanase activity positively correlated with the inflammatory and angiogenic gene expression.
Conclusion & Significance: We also have some evidence to support a postulation that the involvement of heparanase in gene regulation in the development of pannus in RA may be reflected in a patient’s blood, thus heparanase can be a potential predictor of RA progression and a novel therapeutic target.
University Medical Center Maribor, Slovenia
Time : 10:30 - 11:00
Samo K Fokter is a board certified Consultant Orthopedic Surgeon at the Department of Orthopedic Surgery of Maribor University Clinical Centre. He is currently the President of the Expert Council for Orthopedics at Slovenian Medical Association and dedicates a large part of his free time to voluntary work in Mountain Rescue Service of Slovenia. His bibliography contains over 260 units, among them scientific and professional articles, published in high-quality international medical journals. He is a Founding Member of Slovenian Spine Society, Honorary Member of Club Italiano dell’ Osteosintesi (CIO) and also a Chairperson of AOSpine Society. He serves as the Deputy Editor of Springer’s European Journal of Orthopedic Surgery and Traumatology (EJOST), and Editorial Board Member of Zdravniski Vestnik, the central Slovenian medical journal.
Statement of the Problem: Innovations play the key role in the success of orthopedic surgery. However, even minor modifications in the established concepts and proven designs may result in disasters. The endemic of modular femoral neck fracture (23 cases) in fully modular total hip arthroplasty, popular in Central Europe for the last 15 years, seems to challenge us with such an unfortunate consequences.
Methodology & Theoretical Orientation: Literature search for problems associated with Profemur Z (MicroPort Orthopedics Inc., Arlington, TN, USA) fully-modular femoral stem made of titanium alloy (Ti6Al4V) was performed and hip arthroplasty registries were searched to evaluate the failure rates of this specific stem design. Mechanisms of failure were studied to get in-depth understanding of this particular hip reconstruction device.
Findings: Since 2010 onwards, several case reports on catastrophic modular femoral neck fractures of Profemur Z were published. The first Slovenian case was described in 2012. Two small series of patients with sudden modular femoral neck fractures were published in 2016. The Australian Joint Replacement Registry was the first to discover increased revision rates due to fractures of this hip reconstruction system. Corrosion at the neck-taper interface, where two equal or different materials are subject to constant wear in the presence of body fluids, is assumed to be responsible for the unacceptable high failure rate.
Conclusion & Significance: Manufacturers are responsible to produce and market only safe devices. However, orthopedic surgeons should carefully monitor any adverse effect of innovations. As late as in 2015, an urgent field safety corrective notice was sent from the manufacturer indicating that all lots of long modular necks made from cobalt-chromium alloy should be withdrawn. A national arthroplasty registry would probably warn orthopedic community on this questionable innovation earlier.