The Role Of Osteocytes In Particle Induced Osteolysis
Funder
National Health and Medical Research Council
Funding Amount
$457,196.00
Summary
Hip replacements often fail due to the loss of adjacent bone. Metal or polyethylene particles are produced as the prosthesis bearing surface wears but how do these particles lead to bone loss? Our work suggests involvement of osteocytes within the bone mineral, which are increasingly understood to drive bone physiology and pathology. We will explore the role of the osteocytes by examining their response to particles, which may identify a new target to prevent particle-induced bone loss.
We will seek to address an important clinical problem in orthpaedics, namely the bone loss that commonly occurs around joint replacement prostheses. Termed peri-prosthetic osteolysis (PO), this bone loss can result in the loosening and ultimate failure and need for revision of the artificial joint components. PO is thought to be caused by the body's reaction to wear particles generated from the articulating surface of the prosthesis. However, it has not previously been possible to accurately exp ....We will seek to address an important clinical problem in orthpaedics, namely the bone loss that commonly occurs around joint replacement prostheses. Termed peri-prosthetic osteolysis (PO), this bone loss can result in the loosening and ultimate failure and need for revision of the artificial joint components. PO is thought to be caused by the body's reaction to wear particles generated from the articulating surface of the prosthesis. However, it has not previously been possible to accurately explore the relationship between prothesis wear and PO, or the progression of PO, because of a lack of techniques to image and measure the volume of PO around metal prosthesis components. We have developed a means to accurately and reproducibly measure the volume of bone loss, using CT, and will do so longitudinally in joint replacement patients to obtain the first information about the progression of PO. New computer based methods will be used concurrently to relate prosthesis wear and migration parameters to PO. Patients who come to surgery for replacement of failed prostheses will be investigated further by analysis of the tissues involved in the bone loss around prostheses. Basic science experiments will seek to understand the underlying causes of PO and the findings will be important in interpreting the clinical results. An animal model will be used to seek approaches to inhibiting the pathological response to wear particles. The significance of these studies is that they will lead to improved outcomes for joint replacement patients, increasing the interval to revision surgery, which is both extremely costly and brings an attendant morbidity and mortality.Read moreRead less
Determination Of Irradiation Dose Efficacy For Use In Impaction Grafting At Revision Joint Replacement
Funder
National Health and Medical Research Council
Funding Amount
$411,517.00
Summary
Primary hip replacement is a successful intervention for hip disease, but 10-15% of hip prostheses fail and require revision surgery within 10-15 years. At the time of revision, significant bone loss around the failed prosthesis is not uncommon. A bone reconstruction procedure, called impaction grafting, where donor bone is minced and placed in the areas of deficient bone before implanting the new prosthesis, has shown to give good results at more than ten years in some centres. A high incidence ....Primary hip replacement is a successful intervention for hip disease, but 10-15% of hip prostheses fail and require revision surgery within 10-15 years. At the time of revision, significant bone loss around the failed prosthesis is not uncommon. A bone reconstruction procedure, called impaction grafting, where donor bone is minced and placed in the areas of deficient bone before implanting the new prosthesis, has shown to give good results at more than ten years in some centres. A high incidence of early complications of this procedure have included loss of fixation within the bone. Fracture of the bone around prostheses has also reported in some centres. These events require more surgery, putting the patient at higher risk greater complications and longer rehabilitations. Recent improvements in surgical technique and donor bone preparation have improved results. A current debate questions whether the dose of irradiation can be reduced from 25 kGy, while maintaining sterility of allografts. The risk of bacterial contamination in allografts is low, and irradiation reduces the mechanical strength of the graft, contributing to complications when irradiated bone is used. The benefits of decontaminating the bone may be outweighed by the higher risk for failure due to poor bone quality and resulting prosthesis instability. We will use ISO standards to test the validity of radiation dose for sterilising bone ex vivo. In the absence of controlled human studies, our aim is also to compare the results of impaction grafting with non-irradiated bone versus bone irradiated at current doses used by Australian bone banks, and lower doses indicated by ex vivo testing. We will use a large animal model of revision hip replacement, with precise measures of prosthesis stability. The results of this study will guide clinical decisions regarding the efficacy of current bone graft preparation procedures and the use of irradiated bone in human hip replacement surgery.Read moreRead less
The Risks And Benefits Of Contemporary Total Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$493,530.00
Summary
The number of hip replacements undertaken in Australia is steadily increasing. The most common complications of hip replacements are dislocation and loosening due to bone loss around the implant, requiring complex and expensive revision surgery. This study will investigate the incidence of dislocation and, using a new diagnostic imaging technique, the incidence and amount of bone loss around a relatively new prosthetic material, the outcomes of which are not known despite its increasing use.
Safety And Efficacy Of A Surgically Implanted Suprachoroidal Retinal Prosthesis (Bionic Eye)
Funder
National Health and Medical Research Council
Funding Amount
$1,233,826.00
Summary
A bionic eye is a electronic device which can stimulate the remaining visual pathway in a person who is blind, to restore some basic vision. Our team have previously shown that our novel bionic eye device can be safely implanted in a patient, and can give improvements in vision when tested in a laboratory environment. The next stage of the research is to provide patients with a more advanced device, which will contain more electrodes and also be able to be taken home.
Targeting Bone Marrow Lesions To Find Interventions In The Progression Of Osteoarthritis
Funder
National Health and Medical Research Council
Funding Amount
$467,395.00
Summary
It is essential to elucidate the underlying cause(s) of osteoarthritis because our current level of understanding of this condition has failed to produce effective treatments. Lesions in the bone under the cartilage (BMLs), seen using MRI, have strong potential value for the objective monitoring and management of OA. However, because the nature of BMLs is not well understood, the aim of this application is to perform a comprehensive study of BMLs in OA bone.
Improving Visual Outcomes In Patients With Diabetic Macular Oedema Undergoing Cataract Surgery: A Prospective Randomised Clinical Trial (the DiMECat Trial)
Funder
National Health and Medical Research Council
Funding Amount
$187,322.00
Summary
Cataract and diabetic retinopathy are the leading causes of visual loss in patients with diabetes, but unfortunately, cataract surgery in these patients often results in a loss of vision, rather than an improvement. The purpose of this study is to improve the visual outcomes in this group of patients, through the use of new, injected medicines that are given at the time of cataract surgery, thereby potentially changing current medical practice.
Translating Genetic Determinants Of Glaucoma Into Better Diagnosis And Treatment
Funder
National Health and Medical Research Council
Funding Amount
$9,466,000.00
Summary
Glaucoma is the leading cause of irreversible blindness worldwide. By 2020, it will affect 80 million people, and in Australia over the next decade, the overall cost of glaucoma will reach $4.3 billion per annum. This Program will use genetic advances to personalise treatment. Blindness will be prevented in individuals at highest risk, new ways to treat patients will be developed, and better outcomes for patients will result from less treatment and monitoring of low risk cases.
Neuro-feedback For Improved Efficacy Of Retinal Prostheses
Funder
National Health and Medical Research Council
Funding Amount
$653,655.00
Summary
Bionic eyes offer the possibility to return sight to the blind. Existing retinal implants are effective at delivering basic visual percepts, namely brief spots of light. Our team is now working on building the second generation of bionic eyes that include the ability to both stimulate the visual system (the retina) and record its response. By recording the evoked responses, we can adjust and optimize the stimulation to restore a persistent high spatial resolution sense of vision to the blind.
Harnessing Anticalin Technology As A Multi-targeted Treament Approach For Vision Loss
Funder
National Health and Medical Research Council
Funding Amount
$627,273.00
Summary
Diabetes is a leading cause of vision loss and blindness worldwide and is caused by two factors called VEGF and Ang2, which damage blood vessels. Current treatments only block VEGF and many patients do not respond and suffer irreversible damage to sight. We have used ground-breaking anticalin technology to make a new drug (PRS-AUS1) that blocks both VEGF and Ang2. Studies will be performed in animal models and move to patients where we expect improved outcomes compared to current treatments.