Apportioning Deficits In Bone Size And Density In Women With Fractures To Growth Or Ageing By Studies In Their Daughters
Funder
National Health and Medical Research Council
Funding Amount
$196,018.00
Summary
Women fracture their bones because the bones are small and break easily and because the bones are thin or low in denseness (very porous like a honey comb). This study is aimed at identifying why women with fractures have small bones and why the bones are so porous. They may have these problems because they lost a lot of bone as they get older or because growth was abnormal so the size of the bone didn't reach its potential size or because the denseness of the bones didn't develop properly. The s ....Women fracture their bones because the bones are small and break easily and because the bones are thin or low in denseness (very porous like a honey comb). This study is aimed at identifying why women with fractures have small bones and why the bones are so porous. They may have these problems because they lost a lot of bone as they get older or because growth was abnormal so the size of the bone didn't reach its potential size or because the denseness of the bones didn't develop properly. The study will be carried out in women with spine or hip fractures and their daughters. All participants will have bone densitometry, provide a 24 hour urine sample and a fasting blood sample of 20 ml whole blood. Informed consent will be obtained from all participants. The bone density scan is associated with radiation exposure of about 4 mSv, about one tenth of a chest x ray, temporary bruising may follow taking blood. If we can understand the different ways osteoporosis can occur we can then start to devise specific treatments tailored to the individual. Also if we can identify the causes of small bones and bone thinness during growth it may be possible to correct some of these causes before the reduced growth and reduced building of bone occurs. We might also prevent the thinning of bone by identifying and removing causes of bone thinning.Read moreRead less
Is Periosteal Bone Formation Responsible For Sexual Dimorphism In Bone Fragility
Funder
National Health and Medical Research Council
Funding Amount
$316,320.00
Summary
Men and women sustain fractures as they age because their bones become fragile. Women sustain fractures more often than men. Bone thinning occurs in both sexes but it is usually believed that this thinning or loss of bone is greater in women than men. We have evidence to suggest that this may not be correct. In fact, it is likely that men and women lose a similar amount of bone, about half what they started with, but during ageing, men lay down more bone on the outside surface of the bone than w ....Men and women sustain fractures as they age because their bones become fragile. Women sustain fractures more often than men. Bone thinning occurs in both sexes but it is usually believed that this thinning or loss of bone is greater in women than men. We have evidence to suggest that this may not be correct. In fact, it is likely that men and women lose a similar amount of bone, about half what they started with, but during ageing, men lay down more bone on the outside surface of the bone than women compensating for the similar amount lost on the inside of the bone. We also have evidence to suggest than men and women who get spine fractures do so because the process of laying down bone may fail to occur normally. We will study these processes of bone loss inside the bone and bone gain outside the bone to try to better understand why bones become weak. We will measure the bone size and its density in healthy men and women and patients with fractures to determine how the increasing size of the bone produced by laying down bone on its outside helps to keep it strong and to preserve the bone that would otherwise be lost if it didn't occur or if a disease developed that might reduce the compensatoryRead moreRead less
The Effect Of Loading On The Size, Shape And Strength Of Cortical Bone During Different Stages Of Maturation
Funder
National Health and Medical Research Council
Funding Amount
$180,000.00
Summary
Osteoporosis is a condition in which the skeleton becomes fragile and susceptible to fractures. It is a public health problem that affects both men and women over the age of sixty. Although osteoporosis affects the elderly, the most opportune time to prevent osteoporosis may be during childhood. Physical activity is a lifestyle factor known to affect the strength of the skeleton. Bone density is commonly used as a measure of bone strength because it is easily measured and is related to the break ....Osteoporosis is a condition in which the skeleton becomes fragile and susceptible to fractures. It is a public health problem that affects both men and women over the age of sixty. Although osteoporosis affects the elderly, the most opportune time to prevent osteoporosis may be during childhood. Physical activity is a lifestyle factor known to affect the strength of the skeleton. Bone density is commonly used as a measure of bone strength because it is easily measured and is related to the breaking strength of bones. However changes in the shape of bones can also affect bone strength with or without an increase in bone density. Changes in bone shape in response to exercise in children or adults have rarely been investigated, and little is known about the effects of exercise on bone shape during different stages of growth. This study is the first to investigate how exercise during childhood may affect bone strength by changing bone shape. 45 elite female tennis players aged between 6 to 18 years have completed two years of this study. 90 novice and competitive male tennis players aged between 6 to 20 years and 60 healthy age matched controls will be asked to participate in this study. Measurements will be made annually for three years. The bone shape and density of the dominant and non-dominant arms of the players will be compared with the children who don't play tennis - comparisons will also be made between i) different stages of puberty and ii) girls and boys. The findings of this study are important because the lifestyle of children today may predispose them to a greater risk of osteoporosis late in life. Physical activity may be the most important modifiable protective factor against fragile bones in old age. The findings of this study will be the first to provide insight into whether there is a unique time during growth when exercise will result in the greatest increase in bone strength by changing bone shape.Read moreRead less
Structural And Biomechanical Basis Of Differences In Bone Fragility In Asian And Caucasian Men And Women
Funder
National Health and Medical Research Council
Funding Amount
$188,500.00
Summary
Lay Summary Fractures occur less commonly in males than females because males have greater periosteal apposition than females during ageing. This increases bone size (reducing load per unit area - stress), and reduces net bone loss, more in males than females so that the increase in bone fragility with advancing age seen in both sexes is less in males than females. Few males than females have a fracture risk index for vertebral fractures (FRI or ratio of load-bone strength) above unity. The purp ....Lay Summary Fractures occur less commonly in males than females because males have greater periosteal apposition than females during ageing. This increases bone size (reducing load per unit area - stress), and reduces net bone loss, more in males than females so that the increase in bone fragility with advancing age seen in both sexes is less in males than females. Few males than females have a fracture risk index for vertebral fractures (FRI or ratio of load-bone strength) above unity. The purpose of this study is to define the structural and biomechanical basis responsible for the racial differences in fracture rates between Asians and Caucasians. Following the same biomechanical principles as published in Caucasian males and females, we hypothesise that racial differences in periosteal expansion during aging may contribute, in part, to the racial differences in bone fragility at the spine and hip. A cross-sectional study will be conducted in 500 healthy Chinese men and 500 Chinese women age ranged 18 to 90 years living in Melbourne, Australia. We have recruited larger numbers of Caucasian men and women in our Centre. BMD and bone size will be measured at the spine, hip and total body by using dual x-ray bone densitometer (DXA). Vertebral body width, depth, height, cross-sectional area (CSA), stress (load per unit CSA) and fracture risk index (load-strength) at the third lumbar vertebrae will be measured by PA and lateral scanning. Femoral neck periosteal-endocortical diameter, cortical thickness, cross-section moment of inertia (CSMI), section modulus buckling index will be measured by using hip structural analysis program. Just as insight into bone fragility in women has been obtained by studies in men, we believe that the results of this study will provide important insights into the pathogenesis of bone fragility in both racial groups.Read moreRead less