Uniaxial traction test on human gracilis and semitendinous tendon

The use of isolated human tendons as well as in associated forms on knee reconstrution has become na usual practice. The literature reveals that the use of implants of patellar tendon as well as the double semitendinous tendon associated to the double gracilis tendon exhibits different post surgical evolution related to the minimal extension loss, anterior-posterior displacement (KT-1000 artrometer), as well as to the sport activities. This research work aim to analyze the mechanical behavior of human tendons (gracilis and semitendinous) subject to uniaxial traction to failure. The mechanical parameters considered includes: stress at failure (MPa), strain energy at failure (N.mm) and strain rate (mm/mm). Results induced to the following conclusions: - tendon of semitendinous muscle is more resistent than the tendon gracilis muscle; exhibits lower strain, stores higher level of strain energy at failure. - as they present distinct mechanical behavior, it would be necessary to acomplish a more detaield analysis to face the time and history dependence wich are the basic characteristics of viscoelastic materials.O uso de tendões humanos, de forma isolada ou associada, em reconstruções ligamentares do joelho é uma prática usual. A utilização desses enxertos (tendão patelar, duplo semitendinoso associado ao duplo grácil) apresenta evolução pós-operatória diferente, quando analisados os parâmetros : perda mínima da extensão, deslocamento ântero-posterior (artrômetro KT-2000), retorno as atividades esportivas. A presente pesquisa tem por objetivo analisar o comportamento mecânico de tendões humanos (grácil e semitendinoso), quando submetidos a ensaios uniaxiais de tração, até a ruptura. Como parâmetros mecânicos para análise e confronto foram considerados: tensão de ruptura (MPa), deformação relativa, módulo de elasticidade (MPa), energia de ruptura (N.mm) e velocidade de carregamento (mm/s). Os resultados permitiram concluir que: - o tendão do músculo semitendinoso é mais resistente que o tendão do músculo grácil; apresenta menores deformações relativas; acumula maior energia de ruptura; - a utilização destes tendões como enxerto único, impõe uma análise mecânica mais detalhada, pois apresentam comportamento mecânico distinto e são materiais história e tempo - dependentes (viscoelásticos).51

Rehabilitative treatment of cleft lip and palate: experience of the Hospital for Rehabilitation of Craniofacial Anomalies - USP (HRAC-USP) - part 3: Oral and Maxillofacial Surgery

This paper presents the treatment protocol of maxillofacial surgery in the rehabilitation process of cleft lip and palate patients adopted at HRAC-USP. Maxillofacial surgeons are responsible for the accomplishment of two main procedures, alveolar bone graft surgery and orthognathic surgery. The primary objective of alveolar bone graft is to provide bone tissue for the cleft site and then allow orthodontic movements for the establishment of an an adequate occlusion. When performed before the eruption of the maxillary permanent canine, it presents high rates of success. Orthognathic surgery aims at correcting maxillomandibular discrepancies, especially anteroposterior maxillary deficiencies, commonly observed in cleft lip and palate patients, for the achievement of a functional occlusion combined with a balanced face

Rehabilitative treatment of cleft lip and palate: experience of the Hospital for Rehabilitation of Craniofacial Anomalies - USP (HRAC-USP) - Part 3: Oral and Maxillofacial Surgery

This paper presents the treatment protocol of maxillofacial surgery in the rehabilitation process of cleft lip and palate patients adopted at HRAC-USP. Maxillofacial surgeons are responsible for the accomplishment of two main procedures, alveolar bone graft surgery and orthognathic surgery. The primary objective of alveolar bone graft is to provide bone tissue for the cleft site and then allow orthodontic movements for the establishment of an an adequate occlusion. When performed before the eruption of the maxillary permanent canine, it presents high rates of success. Orthognathic surgery aims at correcting maxillomandibular discrepancies, especially anteroposterior maxillary deficiencies, commonly observed in cleft lip and palate patients, for the achievement of a functional occlusion combined with a balanced face

A oesteotomia de Sugioka como tratamento para a osteonecrose da cabeça femoral

Orientador : Gottfried KoberleTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: A Osteotomia Transtrocantérica Rotacional, de Sugioka (OTRS) foi apresentada ao meio ortopédico ocidental em 1978. Sobre o método recaíram grandes esperanças e grandes dúvidas. Ao longo das experiências relatadas por autores ocidentais, a esperança de se ter conseguido um método efetivo foi diminuindo, e as interrogações, se avolumando. (...conitnua)Abstract: Sugioka's Transtrochanteric Rotacional Osteotomy (STRO) was first published in the Western Medical Press, in 1918. It had brought many hopes and many doubts. The experience of occidental orthopedic surgeons with the operation, lessened hopes and accumulated doubts. (...continue)DoutoradoDoutor em Ciências Médica

Ensaio uniaxial de tração dos tendões dos músculos grácil e semitendinoso humanos Uniaxial traction test on human gracilis and semitendinous tendon

O uso de tendões humanos, de forma isolada ou associada, em reconstruções ligamentares do joelho é uma prática usual. A utilização desses enxertos (tendão patelar, duplo semitendinoso associado ao duplo grácil) apresenta evolução pós-operatória diferente, quando analisados os parâmetros : perda mínima da extensão, deslocamento ântero-posterior (artrômetro KT-2000), retorno as atividades esportivas. A presente pesquisa tem por objetivo analisar o comportamento mecânico de tendões humanos (grácil e semitendinoso), quando submetidos a ensaios uniaxiais de tração, até a ruptura. Como parâmetros mecânicos para análise e confronto foram considerados: tensão de ruptura (MPa), deformação relativa, módulo de elasticidade (MPa), energia de ruptura (N.mm) e velocidade de carregamento (mm/s). Os resultados permitiram concluir que: - o tendão do músculo semitendinoso é mais resistente que o tendão do músculo grácil; apresenta menores deformações relativas; acumula maior energia de ruptura; - a utilização destes tendões como enxerto único, impõe uma análise mecânica mais detalhada, pois apresentam comportamento mecânico distinto e são materiais história e tempo - dependentes (viscoelásticos).The use of isolated human tendons as well as in associated forms on knee reconstrution has become na usual practice. The literature reveals that the use of implants of patellar tendon as well as the double semitendinous tendon associated to the double gracilis tendon exhibits different post surgical evolution related to the minimal extension loss, anterior-posterior displacement (KT-1000 artrometer), as well as to the sport activities. This research work aim to analyze the mechanical behavior of human tendons (gracilis and semitendinous) subject to uniaxial traction to failure. The mechanical parameters considered includes: stress at failure (MPa), strain energy at failure (N.mm) and strain rate (mm/mm). Results induced to the following conclusions: - tendon of semitendinous muscle is more resistent than the tendon gracilis muscle; exhibits lower strain, stores higher level of strain energy at failure. - as they present distinct mechanical behavior, it would be necessary to acomplish a more detaield analysis to face the time and history dependence wich are the basic characteristics of viscoelastic materials

Rehabilitative treatment of cleft lip and palate: experience of the Hospital for Rehabilitation of Craniofacial Anomalies - USP (HRAC-USP) - part 3: Oral and Maxillofacial Surgery

This paper presents the treatment protocol of maxillofacial surgery in the rehabilitation process of cleft lip and palate patients adopted at HRAC-USP. Maxillofacial surgeons are responsible for the accomplishment of two main procedures, alveolar bone graft surgery and orthognathic surgery. The primary objective of alveolar bone graft is to provide bone tissue for the cleft site and then allow orthodontic movements for the establishment of an an adequate occlusion. When performed before the eruption of the maxillary permanent canine, it presents high rates of success. Orthognathic surgery aims at correcting maxillomandibular discrepancies, especially anteroposterior maxillary deficiencies, commonly observed in cleft lip and palate patients, for the achievement of a functional occlusion combined with a balanced face