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Abstract(s)
A capacidade de movimento no decorrer de atividades no quotidiano está depende de uma
complexa interação entre várias articulações. A articulação da anca, é das articulações que
desempenha um papel mais importante para os movimentos, levando a que ao longo do tempo,
o esforço repetitivo sobre a mesma leve à sua deterioração e consequente aparecimento de
vários problemas como, por exemplo, osteoartrose.
O tratamento destes problemas na articulação da anca, é feito à base de fisioterapia e
medicação, no entanto nem sempre é suficiente, sendo muitas vezes necessária a intervenção
cirúrgica, como a Artroplastia Total da Anca (ATA). Este tipo de procedimento, é caracterizado
pela substituição da articulação, por uma prótese artificial.
O crescente número de procedimentos de ATA tem impulsionado a investigação sobre o
desempenho e a fiabilidade das próteses utilizadas. A fadiga, um processo de falha progressiva
do material sob cargas cíclicas, destaca-se como sendo um dos principais fatores que
compromete o desempenho das mesmas. Este estudo realizou simulações biomecânicas
através do software COMSOL Multiphysics, em dois designs de hastes protéticas diferentes —
Accolade (anatómica) e Exeter (reta) —, fabricadas em ligas de titânio e Co-Cr. As próteses
foram submetidas a cargas simulando a marcha, para avaliar tensões, e posteriormente aplicar
o método Stress-life para avaliar a resistência à fadiga.
Os resultados mostraram que ambos os designs de haste apresentam longa duração, no
entanto, a haste Exeter demonstrou maior resistência à fadiga. Quanto ao tipo de material, as
próteses de titânio apresentaram melhor desempenho em termos de fadiga em comparação
com as de Co-Cr. O estudo também identificou as áreas mais vulneráveis à falha, verificando
que as mesmas se localizam principalmente na interface osso-implante.
Os resultados reforçam a importância de atribuir a prótese adequada a cada paciente, como
forma de garantir maior longevidade e desempenho do implante.
The ability to move during everyday activities depends on a complex interaction between various joints. The hip joint is one of the most important joints for movement, and over time, repetitive stress on it can lead to its deterioration and the emergence of several issues, such as osteoarthritis. The treatment of these hip joint problems is usually based on physiotherapy and medication; however, this is not always sufficient, and surgical intervention, such as Total Hip Arthroplasty (THA), is often necessary. This type of procedure involves replacing the joint with an artificial prosthesis. The growing number of THA procedures has driven research into the performance and reliability of the prostheses used. Fatigue, a process of progressive material failure under cyclic loads, stands out as one of the main factors compromising prosthesis performance. This study conducted biomechanical simulations using the COMSOL Multiphysics software on two different prosthetic stem designs—Accolade (anatomical) and Exeter (straight)—made from titanium and Co-Cr alloys. The prostheses were subjected to loads simulating walking to evaluate stresses, and the Stress-life method was subsequently applied to assess fatigue resistance. The results showed that both stem designs exhibit long durability; however, the Exeter stem demonstrated greater fatigue resistance. Regarding the material type, titanium prostheses performed better in terms of fatigue compared to Co-Cr prostheses. The study also identified the most vulnerable areas to failure, primarily located at the bone-implant interface. The findings highlight the importance of selecting the appropriate prosthesis for each patient to ensure greater implant longevity and performance.
The ability to move during everyday activities depends on a complex interaction between various joints. The hip joint is one of the most important joints for movement, and over time, repetitive stress on it can lead to its deterioration and the emergence of several issues, such as osteoarthritis. The treatment of these hip joint problems is usually based on physiotherapy and medication; however, this is not always sufficient, and surgical intervention, such as Total Hip Arthroplasty (THA), is often necessary. This type of procedure involves replacing the joint with an artificial prosthesis. The growing number of THA procedures has driven research into the performance and reliability of the prostheses used. Fatigue, a process of progressive material failure under cyclic loads, stands out as one of the main factors compromising prosthesis performance. This study conducted biomechanical simulations using the COMSOL Multiphysics software on two different prosthetic stem designs—Accolade (anatomical) and Exeter (straight)—made from titanium and Co-Cr alloys. The prostheses were subjected to loads simulating walking to evaluate stresses, and the Stress-life method was subsequently applied to assess fatigue resistance. The results showed that both stem designs exhibit long durability; however, the Exeter stem demonstrated greater fatigue resistance. Regarding the material type, titanium prostheses performed better in terms of fatigue compared to Co-Cr prostheses. The study also identified the most vulnerable areas to failure, primarily located at the bone-implant interface. The findings highlight the importance of selecting the appropriate prosthesis for each patient to ensure greater implant longevity and performance.
Description
Keywords
Total hip arthroplasty Prosthetics Prosthetic rush COMSOL multiphysics Fatigue Stress-life Artroplastia total da anca Fadiga Próteses Haste protética