Regulation Of Key Pathways Causing Peri-implant Bone Loss.
Funder
National Health and Medical Research Council
Funding Amount
$403,639.00
Summary
The failure of bone prostheses is becoming a major health problem in our aging population. Despite the impressive success of joint replacement surgery, a significant number of arthroplasties fail. It is now apparent that most implants fail due to bone loss around them which leads to loosening. This project aims to obtain a better understanding of the causes of implant failure and find ways to extend the life of these implants .
Relationship Of The Anabolic And Catabolic Responses In Healing A Critical Sized Defect In Rats
Funder
National Health and Medical Research Council
Funding Amount
$329,750.00
Summary
Delayed bone healing after trauma is a large clinical problem. Figures suggest up to 60,000 fractures result in a delay in healing in Australia per year. Bone healing can also fail to occur in other circumstances, such as after an operation. Research effort into new approaches to solving these problems is clearly justified. We believe that in some situations, bone healing fails due to the body's healing response, the anabolic response, being insufficient. In some other situations, the body's bon ....Delayed bone healing after trauma is a large clinical problem. Figures suggest up to 60,000 fractures result in a delay in healing in Australia per year. Bone healing can also fail to occur in other circumstances, such as after an operation. Research effort into new approaches to solving these problems is clearly justified. We believe that in some situations, bone healing fails due to the body's healing response, the anabolic response, being insufficient. In some other situations, the body's bone resorbing response, the catabolic response, may be too high and prevent healing from occurring. In normal bone healing, there is a balance between the anabolic and catabolic response. In disordered bone healing, these responses are out of balance. Several reasonably new treatments are available which can increase the anabolic response or decrease the catabolic response. We have preliminary results showing that with these agents we can bring these elements into better control, and thus drive bone healing. We have optimised an animal model where both the anabolic and catabolic responses can be controlled. In this project, we explore the optimisation of the timing and magnitude of anabolic and catabolic responses in bone healing.Read moreRead less
The Role Of Muscle And The Application Of Muscle-cell Therapies In Bone Repair
Funder
National Health and Medical Research Council
Funding Amount
$438,936.00
Summary
Muscle is often close to bone and we have found that muscle cells can directly contribute to bone repair. We are examining importance of muscle cells in orthopaedic repair and whether new methods for mobilizing muscle cells can improve healing.
QUANTITATIVE ASSESSMENT OF LOOSENING IN HIP ARTHROPLASTIES USING MECHANICAL VIBRATION DIAGNOSTICS
Funder
National Health and Medical Research Council
Funding Amount
$185,665.00
Summary
Recent advances and improvements made to the mechanical design of artificial joints have led to greater strength, fatigue life and wear resistance. However, this extension to the working life of joint replacements has led to patients becoming increasingly vulnerable to the problem of joint loosening. There are over 500 000 hip joint replacements performed every year, on a worldwide basis. Of these 7 to 13% will require revision surgery because of loosening at some stage of their working life. Th ....Recent advances and improvements made to the mechanical design of artificial joints have led to greater strength, fatigue life and wear resistance. However, this extension to the working life of joint replacements has led to patients becoming increasingly vulnerable to the problem of joint loosening. There are over 500 000 hip joint replacements performed every year, on a worldwide basis. Of these 7 to 13% will require revision surgery because of loosening at some stage of their working life. This is becoming a major concern to health services around the world since revision surgery is associated with a higher risk to the patient and costs are far greater than for the primary operation. Current diagnostic techniques using radiographic imaging are both invasive and lack diagnostic accuracy. The ability to detect joint loosening and to discriminate between the various causes of joint loosening following arthroplasty is of great importance to the success of subsequent care plans. This study will be the first in the world to assess the validity of a new diagnostic test that uses low energy mechanical vibration to quantify the degree of loosening in both components of the implanted hip joint. Once the technique has been proven it could readily be extended to evaluate the degree of fixation of other implanted prostheses used to replace the knee, ankle or joints of the upper limbs.Read moreRead less
An RCT To Determine The Optimum Frequency Of Botulinum Toxin Injections To The Calf In Children With Cerebral Palsy
Funder
National Health and Medical Research Council
Funding Amount
$286,358.00
Summary
Cerebral Palsy (CP) is the most common cause of disability amongst children across the developed world. There are about 1800 children with CP in Victoria alone. It is caused by damage to the brain in early childhood. Children with CP have difficulty controlling how their muscles work. Muscles are often spastic, which means that they are switched on all the time, and this makes walking and performing other tasks difficult. As the child grows the spastic muscles can become too short and this occur ....Cerebral Palsy (CP) is the most common cause of disability amongst children across the developed world. There are about 1800 children with CP in Victoria alone. It is caused by damage to the brain in early childhood. Children with CP have difficulty controlling how their muscles work. Muscles are often spastic, which means that they are switched on all the time, and this makes walking and performing other tasks difficult. As the child grows the spastic muscles can become too short and this occurs can only be corrected by orthopaedic surgery. The spasticity in particular muscles can be reduced by injecting them with Botulinum Toxin (commonly known as Botox and used cosmetically to remove wrinkles). The effects of a single injection have been closely studied and we know that the effect of the toxin wears off. Children are thus offered repeat injections but there have been no studies to investigate what is the most appropriate interval between injections. The aim of this study is to determine this. In routine clinical practice children tend to get injections approximately once a year. A consideration of what we know about how the toxin acts, however, suggests that injections every 4 months might be expected to be more effective. This study will thus randomly allocate children to receive injections either every twelve months or every four months over a two year period. During the study both groups will be monitored to see if there are differences in how easily they can walk and perform other functions and in their overall quality of life. After the study the children will also be assessed to see whether there is any difference in the length of the spastic muscles. There have been no other studies to investigate the most appropriate interval between injections. This study will thus be the first anywhere and will be the foundation for guidelines for the ongoing use of botulinum toxin in children with cerebral palsy in Australia and throughout the world.Read moreRead less
Novel Therapeutic Interventions For The Orthopaedic Complications Of Neurofibromatosis Type 1 (NF1).
Funder
National Health and Medical Research Council
Funding Amount
$628,422.00
Summary
Children with the genetic disease NF1 can develop fractures that fail to unite and this can lead to amputation. We have advanced models of NF1-deficient bone cells and fracture healing that we will use to test new pharmaceutical treatments for NF1.
Antibiotic Loading Of Bone Allografts For The Prevention Of Peri-operative Infection
Funder
National Health and Medical Research Council
Funding Amount
$300,847.00
Summary
Bone is the second most often transplanted tissue after blood, with thousands of grafts done every year in Australia. Allograft bone (taken from another person) is used to replace bone removed due to cancer, but is prone to infection. Infected grafts must be removed, and can lead to amputation. We are developing a process to put antibiotics into allograft bone, to prevent infections from taking hold. Reducing infections can increase the success of limb salvage surgery for cancer patients.
Role Of The Osteoclast In Endochondral Fracture Repair
Funder
National Health and Medical Research Council
Funding Amount
$310,136.00
Summary
Failure of bone healing leads to significant pain and disability, such that augmentation of fracture repair is a dynamic and important field of study. A full understanding of bone repair is necessary before we can hope to introduce successful therapies. We theorise that by stimulating bone forming cells and inhibiting bone resorbing cells we may be able to provide optimal results. Bone resorbing cells, or osteoclasts, have long been considered essential to the initial stages of bone repair (endo ....Failure of bone healing leads to significant pain and disability, such that augmentation of fracture repair is a dynamic and important field of study. A full understanding of bone repair is necessary before we can hope to introduce successful therapies. We theorise that by stimulating bone forming cells and inhibiting bone resorbing cells we may be able to provide optimal results. Bone resorbing cells, or osteoclasts, have long been considered essential to the initial stages of bone repair (endochondral ossification) during which the early soft cartilaginous callus is replaced by hard mineralised callus. Our preliminary studies lead us to believe that endochondral ossification can indeed proceed without osteoclast activity. If we can safely eliminate osteoclast function early in the early stages of fracture repair, a number of therapeutic options open up for the augmentation of bone healing. The return of osteoclast function is necessary in the long term, so our strategy will also need to take this into account. This study will establish which systems are pivotal in endochondral ossification and therefore which interventions we should explore.Read moreRead less
ANALYSIS OF KNEE KINEMATICS- An MRI Study Of The Normal, Anterior Cruciate Injured, And Reconstructed Knee.
Funder
National Health and Medical Research Council
Funding Amount
$161,320.00
Summary
People with anterior cruciate ligament damage to the knee tend to develop osteoarthritis in this knee, perhaps because the instability produced by the ligament tear changes the patterns of wear on the joint surfaces. There are several studies using cadaver knees which examine the impact on the joint surfaces of cutting the anterior cruciate ligament, but very little of people moving voluntarily. This study plans to use MRI images of people with a torn cruciate ligament in one knee, and one norma ....People with anterior cruciate ligament damage to the knee tend to develop osteoarthritis in this knee, perhaps because the instability produced by the ligament tear changes the patterns of wear on the joint surfaces. There are several studies using cadaver knees which examine the impact on the joint surfaces of cutting the anterior cruciate ligament, but very little of people moving voluntarily. This study plans to use MRI images of people with a torn cruciate ligament in one knee, and one normal knee. The subjects will simulate a squat inside the MRI magnet against a weighted footplate. The images will be taken at fifteen degree intervals of knee movement. The contact points between the joint surfaces will be measured and compared to the normal knee. This imaging will be repeated after surgical repair, and then again two years later, to assess whether the normal movement pattern has been restored.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.