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 Next Generation Of Biomaterials; In Vivo Assessment Of Lumbar Spinal Fusion Biodegradable Interbody Cages
Funder
National Health and Medical Research Council
Funding Amount
$85,932.00
Summary
Back pain represents one of the major health and economic problems facing the western world. Surgery is an inevitable outcome for many sufferers and involves the implantation of metallic rods screws, plates or cages. Biodegradable implants have theoretical advantages, but until now no material has existed that can sustain he rigours of implantation into a load bearing site. We have developed such a material which will lead to improvements in the treatment of many orthopaedic conditions.
Cartilage Destruction In Joint Disease: Studies With ADAMTS-4 And ADAMTS-5 Deficient Mice
Funder
National Health and Medical Research Council
Funding Amount
$540,600.00
Summary
In healthy joints the proteoglycan, aggrecan, gives cartilage compressive resilience to permit weight bearing, but in disease aggrecan is degraded by ADAMTS enzymes. The challenges to the field are to determine which ADAMTS is involved, when these enzymes are active and precisely where they come from. We hypothesise that ADAMTS-4 and-or ADAMTS-5 is involved in cartilage pathology. To test this hypothesis we aim to [1] Generate mice containing mutant ADAMTS-4 and-or -5 in all cells, or [2] in car ....In healthy joints the proteoglycan, aggrecan, gives cartilage compressive resilience to permit weight bearing, but in disease aggrecan is degraded by ADAMTS enzymes. The challenges to the field are to determine which ADAMTS is involved, when these enzymes are active and precisely where they come from. We hypothesise that ADAMTS-4 and-or ADAMTS-5 is involved in cartilage pathology. To test this hypothesis we aim to [1] Generate mice containing mutant ADAMTS-4 and-or -5 in all cells, or [2] in cartilage cells only. [3] Analyse mutant mice for changes in skeletal architecture, changes in ADAMTS mRNA and protein, and changes in aggrecan breakdown products. [4] Assess disease severity in mutant mice in in vivo models of joint disease. We already have mice with ADAMTS-4, or -5, mutated in all tissues and we are generating the double mutants now. We will also generate single and double mutants with dysfunctional enzymes in cartilage only. We will examine skeletal structure by histology and X-ray at all ages and monitor for expression of ADAMTS-1 and -9 to detect any compensatory over-production of other potential 'aggrecanases'. We will also do co-culture experiments in which cartilage and synovial cells from combinations of mutant and control mice will be incubated together to determine whether synovial ADAMTS can penetrate and degrade aggrecan in cartilage. Finally we will induce arthritis in mutant and control mice and monitor them to detect differences in the time of disease onset, the rate of disease progression and overall disease severity. A comparison of whole-mouse with cartilage only mutants in the in vivo models will complement the in vitro co-culture studies and determine whether other joint tissues such as synovium and joint capsule can also produce ADAMTS enzymes that destroy cartilage. This is not known. Together these experiments will reveal if, where and when ADAMTS-4 and-or -5 are active, and whether indeed they are the best targets for drug development.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