Dissertação

{en_GB=Computational analysis of the effect of physical activity on the changes in femoral bone density in prepubertal children} {} EVALUATED

{pt=Human bone health, and osteoporosis in particular, are a highly topical research. A causal and positive effect of physical activity on bone mineral density is supported by a bunch of clinical-based research studies. Moreover, actual research suggests long-term benefits of childhood physical activity to the prevention of osteoporosis in adulthood. Complementary to the clinical-based study is the computational analysis, based on a bone remodeling model. Although many different remodeling models are developed by several research groups, very little research is done in the application of computational remodeling in children. The current study is performed in this gap and consists of two major parts. First, a model is developed to represent the femoral bone of a prepubertal child. In the second part of the research, the effect of additional physical activity on bone mineral density is investigated. It is concluded that results of the computational model are in agreement with clinical results. Spending more time in physical activity, high-intensive activity in particular, bone mineral density increases. It is stated that an initial increase in activity time leads to a greater increase in bone mass compared to a further increase in activity time. Further, the results suggest that physical activity decreases the risk for typical (osteoporotic) femoral fractures, as suggested by former research. In the region of the femoral neck, this happens by the periosteal apposition of bone: a relative increase in density of the outer shell. In the trochanteric region, the fracture risk is decreased by an increased bone mineral density., en=Human bone health, and osteoporosis in particular, are a highly topical research. A causal and positive effect of physical activity on bone mineral density is supported by a bunch of clinical-based research studies. Moreover, actual research suggests long-term benefits of childhood physical activity to the prevention of osteoporosis in adulthood. Complementary to the clinical-based study is the computational analysis, based on a bone remodeling model. Although many different remodeling models are developed by several research groups, very little research is done in the application of computational remodeling in children. The current study is performed in this gap and consists of two major parts. First, a model is developed to represent the femoral bone of a prepubertal child. In the second part of the research, the effect of additional physical activity on bone mineral density is investigated. It is concluded that results of the computational model are in agreement with clinical results. Spending more time in physical activity, high-intensive activity in particular, bone mineral density increases. It is stated that an initial increase in activity time leads to a greater increase in bone mass compared to a further increase in activity time. Further, the results suggest that physical activity decreases the risk for typical (osteoporotic) femoral fractures, as suggested by former research. In the region of the femoral neck, this happens by the periosteal apposition of bone: a relative increase in density of the outer shell. In the trochanteric region, the fracture risk is decreased by an increased bone mineral density.}
{pt=Bone mineral density, Finite element modeling, Prepubertal children, Bone remodeling, Lisbon model, Subject specific modeling, en=Bone mineral density, Finite element modeling, Prepubertal children, Bone remodeling, Lisbon model, Subject specific modeling}

junho 23, 2015, 11:0

Publicação

Obra sujeita a Direitos de Autor

Orientação

ORIENTADOR

Maria de Fátima Baptista

FMH-UL

Professor Associado

ORIENTADOR

Paulo Rui Alves Fernandes

Departamento de Engenharia Mecânica (DEM)

Professor Associado