Research Showcase

Examples of orthopaedic research being conducted by, or in collaboration with, AOA members:

Surgical Site Infections

Researchers: T Peel, M Dowsey, P Choong

This research group focuses on strategies to prevent and optimise treatment of infections following surgery. Specifically, surgical site infections following orthopaedic surgery, including prosthetic joint replacement surgery.

The research program was developed by Dr Trisha Peel, Dr Michelle Dowsey and Prof Peter Choong, and includes a number of streams of evidence based research such as randomised controlled trials, prospective cohort studies and basic science research.

Dr Trisha Peel is a chief investigator at the NHMRC National Centre for Antimicrobial Stewardship: One Health Approach.

Bone Regeneration

Researchers: D Hutmacher, M Schuetz, P Choong, I Dickinson, M Woodruff, D Epari, R Steck

The regeneration of large bone defect occurring through trauma, tumour and infection, remains a challenging surgical issue. Currently, well-established clinical therapeutic approaches for bone reconstruction are restricted to the transplantation of autografts and allografts, and the implantation of metal devices or ceramic-based implants to assist bone regeneration.

Bone grafts possess osteoconductive and osteoinductive properties, however, they are limited in access and availability, and associated with donor-site morbidity, hemorrhage, risk of infection, insufficient transplant integration, graft devitalization, and subsequent resorption, resulting in decreased mechanical stability. As a result, recent research focuses on the development of alternative therapeutic concepts.

The field of tissue engineering has emerged as an important approach to bone regeneration. Using an established ovine preclinical segmental defect model (three and six centimetres), our group is investigating the effectiveness of a range of biofabricated tissue engineering constructs in combination with cells, graft material or growth factors, for the regeneration of bone defects.

The development and application of a range of in vivo monitoring and ex vivo analytical tools allows functional assessment of the treated limb and characterisation of the quality and quantity of the new formed bone. These studies constitute a vital role in the translation of orthopaedic bone engineering from bench to bedside.

Bone regeneration

Figure 1: mPCL-TCP scaffold (A, B, C), six centimetre tibial defect before (D) and after insertion of the scaffold (E). Application of fixation, post-operative x-ray showing stable fixation of the defect (F).

Improving Outcomes for Total Joint Replacement Patients

Researchers: JM Naylor, H Badge, IA Harris

Outcomes after total knee or total hip replacement (TKR, THR) are affected by surgical and care processes as well as patient characteristics.

Widespread variation in such processes exists between service providers. Unnecessary variation contributes to increased costs of care and variation in patient outcomes.

This study, by monitoring providers and patients through their joint replacement and post-operatively, aims to:

identify the level of service provider compliance with current practice recommendations
identify whether compliance with current recommendations is associated with better outcomes
identify comparative costs associated with specific practices or processes
generate a cost-effective model to help standardise care.

This study has recruited nearly 2000 patients from private and public hospitals across Australia.

By identifying areas of practice variation and factors associated with better outcomes, we aim to improve the outcomes for total joint patients in the future.

Cartilage and Bone Regeneration

Research Lead: P Choong

The advanced limb reconstruction program at St Vincent’s Hospital was developed to address the physical and functional deficits that follow trauma, degeneration and tumour resection. The traditional methods of treating such deficits include prosthetic and biologic reconstructions, or a combination of these two.

Advances in nanotechnology, electromaterials science, advanced materials manufacturing and tissue engineering and regeneration have opened a new era of limb reconstruction, making it possible to reconstruct tissue using excitable materials interfacing with biologic tissue and stem cells.

Prof Peter Choong leads a team in exploring new ways of reconstructing cartilage and bone defects using bioscaffolds and stem cells, as well as repairing muscle defects using electropolymers.

Biomechanics of Fracture Healing

Researchers: D Epari, M Schuetz

An improved understanding of bone regeneration mechanisms represents a significant opportunity to improve quality of life and reduce the economic burden associated with extended disability arising from fracture non-unions.

The impairment of the healing process has been dependent on both the biological and mechanical environment. Understanding the mechanobiology of bone healing has been hampered by limitations in the ability to control the mechanical boundary conditions during bone healing.

This study utilises a highly innovative experimental bone healing model and active fixation system that enables precise control of the mechanical environment and real time monitoring of the progression of healing. The application of this model will allow the investigators, for the first time, to investigate clinically relevant research questions such as the effect of single extreme loading events on healing, and the potential for intelligent and adaptive fixation devices to accelerate healing.

In combination with computational modelling approaches, this study will lead to an enhanced understanding of the influence of the mechanical environment on bone healing. The research has the potential to inform the development of new fixation strategies, rehabilitation protocols and to lead to novel therapeutic treatments for bone regeneration.

Models Models2

Figure 1: Coupling computer models with tightly controlled boundary conditions, in experimental models of bone healing, allows the influence of the mechanical environment to be elucidated on the biological processes of bone healing.

Wrist Fractures in the Elderly

Researchers: IA Harris, JM Naylor, Z Balogh, P Smith, H Drobetz, M Richardson, M Chehade, C Morrey, N Ward, C Hoffman, G Smith, R Walker, J Mulford, A Oppy, M Wren, W Xuan, K Howard, P Tamblyn, M Gupta, B Schick, I Incoll, I Elkinson, S Viswanathan, H Lombard, P Tran, A Hatfield, R Buchbinder, R Ivers

Displaced fractures around the wrist in older patients represent one of the most common fractures treated by orthopaedic surgeons, yet treatment methods vary widely: the two most common methods being fixation with a plate (requiring admission to hospital and surgery), and manipulation of the fracture and immobilisation in a plaster cast (which may be done as an outpatient, in the emergency department).

There is currently very little high quality scientific evidence to guide surgeons on the best treatment, given the variety of costs, risks and benefits between these two very different treatment alternatives.

A large group of researchers from across Australia and New Zealand have come together to answer this question with a multicentre randomised trial comparing these two treatments. This study will address a large gap in the evidence around the treatment of this common fracture.

Outcomes of Arthritis Surgery

Researchers: P Choong, M Dowsey

Musculoskeletal disorders are the second largest global contributor to years lost through disability. Osteoarthritis of the hip and knee is the third most prevalent condition in this group of disorders.

Under the leadership of Prof Peter Choong and Dr Michelle Dowsey, a high fidelity surgical database at St Vincent’s Melbourne Arthroplasty and Outcomes (SMART) registry has been maintained, since 1998. The registry provides material for analysing the various patient, prosthetic and treatment factors that impact patient outcomes and prosthesis survival.

The SMART registry has been central to identifying risk factors for poor surgical outcomes and providing the foundation for our program of research. We lead a program of research that aims to improve access to and outcomes from total joint replacement in collaboration with a team of national and international experts in:

arthritis surgery
outcomes research
primary care
mental health
infectious diseases
biomechanics
rehabilitation
health economics and risk analysis
implementation science
health workforce
health service delivery