A avaliação funcional após a artroplastia total de joelho (ATJ) tem o intuito de analisar como os resultados alcançados após a cirurgia impactam na qualidade de vida e função dos pacientes. Questionários subjetivos de auto percepção da função são os instrumentos mais utilizados, porém, tendem a superestimar a função física. Os testes de desempenho físico avaliam objetivamente o que o indivíduo é capaz de executar, mas avaliam tarefas isoladas que nem sempre refletem a mobilidade nas atividades de vida diária. Portanto, o objetivo deste estudo foi analisar o quanto a avaliação funcional, que incluiu questionários subjetivos e testes de desempenho físico, permite avaliar as mudanças ocorridas longitudinalmente após a ATJ e permite estabelecer fatores pré e pós-operatórios preditivos da função após um ano de cirurgia. Foi realizado estudo longitudinal prospectivo com 87 sujeitos (62 mulheres), idade 67±7 anos, IMC 33±5 kg/m2, submetidos à ATJ primária unilateral. A avaliação ocorreu no pré-operatório e 3, 6 e 12 meses após a cirurgia. Análise da covariância analisou as mudanças ao longo do tempo e a árvore de classificação e regressão estabeleceu os fatores preditivos. O questionário subjetivo WOMAC-função e os testes de desempenho físico timed up and go (TUG) e teste de caminhada de seis minutos (TC6) aos 12 meses de pós-operatório foram as variáveis primárias. A idade, índice de massa corpórea (IMC), WOMAC-dor, função pré-operatória e força muscular do joelho operado e não operado, tanto pré quanto pós-operatoriamente, foram estabelecidas como variáveis secundárias. Os resultados mostraram que WOMAC e o TUG atingiram platô de evolução aos três meses de pós-operatório, enquanto oTC6 alcançou o platô aos seis meses de pós-operatório. Com relação aos fatores pré- operatórios preditivos da função após 12 meses de cirurgia, indivíduos com TUG <=19 s e idade entre 62 e 70 anos alcançaram melhor pontuação no WOMAC-função. Sujeitos com força dos músculos extensores do joelho não operado >=99 Nm/kg e TC6 >328 m antes da cirurgia percorreram maior distância no TC6. Sujeitos com TUG =421 m no pré-operatório obtiveram melhor desempenho no TUG. Sobre os fatores pós-operatórios preditivos da função, sujeitos com WOMAC-dor < 1,5 pontos, TC6 >=410 m e TUG < 8 s apresentaram melhor pontuação do WOMAC-função. Sujeitos com TUG <9 s e força dos músculos extensores do joelho operado >=113 Nm/kg apresentaram melhor desempenho no TC6. Sujeitos com TC6 >=421 m e força dos músculos flexores do joelho não operado >=47Nm/kg foram mais rápidos na execução do TUG. Concluímos que os questionários subjetivos e os testes de desempenho físico apresentaram diferentes comportamentos de evolução ao longo de um ano de pós-operatório de ATJ. Sujeitos com melhor desempenho físico pré e pós-operatório apresentam melhor pontuação no WOMAC-função após a cirurgia e sujeitos com pior dor pós-operatória apresentaram pior percepção da função no mesmo período. Os fatores de maior predição dos testes de desempenho físico foram a função pré-operatória e a força muscular pré e pós-operatória. / The functional evaluation after total knee arthroplasty (TKA) is intended to analyze how the results achieved by the surgery affect the quality of life and function of patients. Subjective patient-report outcomes measures are the most commonly used instruments, but tend to overestimate physical function. Physical performance tests objectively evaluate what the individual is capable to perform, but evaluate isolated tasks that do not always reflect mobility in activities of daily living. Therefore, this study was aimed to analyze how functional evaluation, which encompassed subjective questionnaires and physical performance tests, enables us to evaluate the changes occurred longitudinally after TKA and to establish pre and post-operative predictive factors of this function one year after surgery. We performed a prospective longitudinal study with 87 individuals (62 women), age 66.9±6.66 years, BMI 32.5±5 kg/m2, submitted to unilateral primary TKA. The evaluation took place in the pre-operative period and 3, 6 and 12 months after surgery. The analysis of covariance assessed the changes over time, whereas the classification and regression tree established the predictive factors by considering the WOMAC-function questionnaire and the physical performance tests Timed Up and Go (TUG) and Six-minute Walk Test (6MWT) at 12 months post-operative as primary variables. Age, body mass index (BMI), WOMACpain, pre-operative function, and knee muscle strength, both pre-operatively and postoperatively, were set up as secondary variables. The results showed that the subjective questionnaires and the TUG tests reached a plateau of evolution at three months post-operative, while the 6MWT tests reached the plateau at six months postoperative. Regarding the pre-operative predictive factors of the function at 12 months after surgery, individuals with TUG<=19.3 seconds, aged between 62 and 70 years achieved a better score in the WOMAC-function one year after surgery. Individuals with non-operated knee extensor muscle strength >=99.43 Nm/kg and 6MWT >328 meters before surgery walked a longer distance in the 6MWT test. Individuals with TUG <12.3 seconds and 6MWT>=421 meters in the pre-operative period achieved better TUG performance. As for the post-operative predictive factors of the function, individuals with WOMAC-pain<1.5 points, 6MWT>=410.2 meters and TUG <7.90 seconds showed better scores of the WOMAC-function. Individuals with TUG<9.44seconds and operated knee extensor muscle strength>=112.8 Nm/kg showed better performance in the 6MWT test. Individuals with 6MWT>=421 meters and non-operated knee flexor strength>=47 Nm/kg were faster in executing the TUG test. We concluded that the subjective questionnaires and the physical performance tests showed different evolutionary behaviors during the first year after the TKA surgery. Individuals with better pre and post-operative physical performance show better scores in the WOMAC-function after surgery, while individuals with worse post-operative pain show worse perception of the function in the same period. The most predictive factors of the physical performance tests were pre-operative function and pre and post-operative muscle strength.

Contexto: O objetivo do estudo foi avaliar a reprodutibilidade intra e interobservador da versão acetabular e femoral da prótese total de quadril. Materiais e métodos: estudo prospectivo incluindo 101 indivíduos submetidos a prótese total de quadril, sendo 114 quadris desde 2008, com imagens de tomografia computadorizada incluindo os componentes acetabular e femoral da prótese e os côndilos femorais. Resultados: Para avaliação intraobservador o coeficiente de correlação interclasse foi para o observador A de 0.99 para versão acetabular e femoral com intervalo de confian- ça (IC) de 0.98-1.00, para o observador B de 0.98 para versão acetabular (IC de 0.97- 0.99) e de 0.88 para versão femoral (IC de 0.83-0.92), para o observador C de 0.98 para versão acetabular (IC de 0.97-0,99) e de 0.83 para versão femoral (IC de 0.76-0.88). Para avaliação interobservador o coeficiente de correlação interclasse foi calculado com as medidas da primeira leitura de cada observador e em seguida da segunda leitura, sendo a primeira leitura da versão acetabular de 0.99 (IC de 0.98-1.00), a segunda leitura da versão acetabular de 0.99 (IC de 0.98-1.00), a primeira leitura da versão femoral de 0.99 (IC de 0.98-1.00), a segunda leitura da versão femoral de 0.96 (IC de 0.94-0.97). Conclusão: Com os resultados obtidos, podemos concluir que as medidas tomográficas de versão acetabular possuem excelente reprodutibilidade tanto inter quanto intraobservador, as medidas de femoral possuem excelente reprodutibilidade interobservador e de boa a excelente reprodutibilidade intraobservador. / Context: The objective of the study was to evaluate the reproducibility intra e interobserver of acetabular and femoral version after total hip arthroplasty. Materials and methods: prospective studying including 101 individuals after total hip arthroplasty, 114 hips since 2008, with computed tomography images including the components of acetabular and femoral prothesis and the femoral condyle. Results: intra-observer coefficient of interclass correlation was 0.99 for observer A for acetabular and femoral version (IC of 0.98-1.00), for B 0.98 for acetabular version (IC of 0.97-0.99) and 0.88 for femoral version (IC of 0.83-0.92), for C 0.98 for acetabular version (IC of 0.97-0.99) and 0.83 for femoral version (IC of 0.76-0.88). For inter-observer evaluation, the interclass correlation coefficient was calculated with the measurements of the first reading of each observer and the second reading, the first reading of the acetabular version was 0.99 (IC of 0.98-1.00), the second reading of the acetabular version was 0.99 (CI 0.98-1.00), the first reading of the femoral version was 0.99 (CI of 0.98-1.00), the second reading of the femoral version was 0.96 (CI of 0.94- 0.97). Conclusion: With the results obtained, we can conclude that the tomographic measurements of acetabular version have excellent inter- and intraobserver reproducibility, femoral measurements have excellent interobserver reproducibility and good to excellent intraobserver reproducibility.

Ph.D.,Dept. of Orthopaedic Surgery, Faculty of Health Sciences, University of the Witwatersrand, 2009. / Total hip replacement (THR) is an effective method of treatment for patients with hip disability. The procedure is capable of providing long-term functional improvement with excellent control of pain and restoration of function. Sir J Charnley developed a concept of low friction arthroplasty, which was based on use of ultra-high molecular weight polyethylene acetabular and stainless steel femoral components. The components were attached to bone with the use of polymethylmethacrylate (PMMA) bone cement. This concept has been very successful, and is considered the gold standard of THR. Aseptic loosening of the prosthetic components remains the single most important reason for failure of THRs. Wear to the ultra high molecular weight polyethylene (UHMWPE) acetabular cup is a well-known cause of osteolysis and aseptic loosening of the components. Thus, substantial improvement to the wear resistance of UHMWPE could extend the clinical life span of total hip replacements. In an attempt to reduce polyethylene wear and subsequent osteolysis, a method was developed in the early seventies in South Africa to improve polyethylene quality by means of gamma ray cross-linking. The acetabular cup was irradiated with 100 Kilogray in an acetylene environment, which was used as a cross-linking gas material, resulting in improvement of UHMWPE wear resistance. Influenced by the world trend and with the advent of a ceramic bearing surface, the Project of cross-linking was, to a certain extent, forgotten. Patients followed up in the late 1990s, showed minimal or total absence of wear after 15 years or longer. 3 Based on my preliminary studies, and anticipating the world trend of acceptance of cross- link UHMWPE, the aim of this research is to consolidate the results from the largest long term group of patients with acetylene cross-link UHMWPE, to study polyethylene gamma irradiated in the presence of a cross-linking acetiylene gas and the effects of it, in vitro, using a hip simulator. I was planning to communicate with as many patients as possible from the group operated on from 1977 until 1983 in whom cross-link UHMWPE was used. This group of over thousand patients represents the largest group of patients with cross-linked UHMWPE acetabular components in the world, with the longest clinical follow up of over 20 years on average. The first part of the research is a retrospective study: The goal was to contact as many patients as possible who were operated on during the period 1977 to 1983 when cross-linked polyethylene was used. To qualified for the study each patient had to have an early postoperative and the latest follow up radiograph. The radiological study consisted of the radiological measurement of wear. For this purpose the Hip Analysis Suite program was used. This is a software program designed by Dr John M. Martell from the University of Chicago, which is widely used and internationally accepted for that purpose. Image analysis offers significant improvements in reproducibility and accuracy when compared to manual analysis. 4 The final results were compared with results of polyethylene wear in patients in whom conventional UHMWPE was used. For this comparison only patients with acetabular components made from the same UHMWPE material and from the same supplier were used. The conventional UHMWPE is a component of the gold standard of hip replacement surgery. World-wide published follow up studies of 15 years and longer using conventional UHMWPE were compared to the cross-link UHMWPE group. If revision surgery was indicated for whatever reason in patients in with cross-linked UHMWPE acetabular components, the retrieved prosthesis was analyzed. The analysis consisted of examination of the articular surface of the cross-linked acetabular component for micro wear phenomena using a Scanning Electron Microscope (SEM). In order to perform an objective analysis of the retrieved components, two independent laboratories were used, namely: Peterson Tribology Laboratory, Loma Linda University, California, and Biomechanical Laboratory, Faculty of Engineering, University of Pretoria. The analyses were possible thanks to collaboration with Dr Ian Clark from Peterson Tribology Laboratory and Dr NDL Burger in charge of the Biomechanical Laboratory at the Department of Engineering, University of Pretoria

Student Number: 9602675T Master of Science in Physiotherapy. Faculty of Health Sciences / The purpose of the study was to compare the outcome in patients following primary total hip arthroplasty, between those receiving a mobility programme alone, as compared to bed exercises and a mobility programme, at discharge from hospital. Thirty-six patients were randomly allocated to either the control or experimental group using a concealed allocation process. The control group received a programme of supervised bed exercises and were mobilised according to the standard postoperative mobility protocol. The experimental group were mobilised according to standard protocol. On the third/fourth and sixth/seventh day postoperatively, patients were assessed by a blinded assessor on functional ability, pain at rest, and active range of hip flexion and abduction. The results indicated no difference in functional ability (p=0.99), pain at rest (p=0.83) and active range of hip flexion (p=0.19) or abduction (p=0.12), on the seventh/eight day postoperatively, between the control and experimental groups. In conclusion bed exercises appear to offer no additional benefit to patients post THA, during the acute hospitalisation phase. However this should not be extrapolated to THA patients who have prolonged bed rest periods postoperatively.

As progressivas inovações tecnológicas, na área de projeto mecânico, contribuem para a adoção de novos procedimentos cirúrgicos relacionados à ortopedia. Este trabalho trata do projeto, desenvolvimento e fabricação de dispositivos de usinagem e instrumentais cirúrgicos para aplicação em cirurgias de recapeamento da cabeça femoral em humanos e animais, buscando aperfeiçoar tal procedimento no que diz respeito a tecnologias voltadas à modelagem óssea e furação centralizada com a cabeça femoral. Nesse contexto, a relação tempo x precisão foi muito bem explorada, de forma a auxiliar com eficiência os cirurgiões e os pacientes que necessitam dessa cirurgia reduzindo a interferência da habilidade do cirurgião no resultado final da cirurgia. A fresa multilaminar sequencial, criada para usinar a cabeça femoral conforme geometria interna da prótese de recapeamento de quadril é uma importante ferramenta para redução do tempo de cirurgia, uma vez que é necessária a troca de ferramentas durante os procedimentos cirúrgicos como mostrado nesta tese. O instrumental cirúrgico, responsável para o funcionamento correto desses dispositivos de usinagem, é um guia de furação personalizado capaz de alinhar a broca e a fresa durante a modelagem da cabeça femoral, de acordo com o ângulo do colo femoral de cada paciente. Assim, este trabalho trata da concepção, desenvolvimento e fabricação de protótipos de um dispositivo de usinagem e instrumentais cirúrgicos que promovam a usinagem centralizada seguindo o ângulo do colo femoral, redução do tempo de cirurgia e da aplicação cirúrgica com prótese de recapeamento artroplastia de recapeamento canina. Os produtos desenvolvidos nesse trabalho serão nomeados como \"fresa multilaminar sequencial\", \"máscara para furação centralizada\" e \"prótese e instrumentais cirúrgicos para cães\", para a artroplastia de recapeamento de quadril. Com os desenvolvimentos, é esperada uma redução no tempo da cirurgia, bem como um aumento na segurança, possibilitando maior sucesso nesses procedimentos em humanos, bem como trás nova tecnologia para a medicina veterinária. / Progressive technological innovations in the area of mechanical design, contribute to the adoption of new surgical procedures related to orthopedics. This work addresses the design development and manufacture of machining devices and surgical instruments to be used in resurfacing surgeries of the femoral head in humans and animals, seeking to improve this procedure in regards to a new technology related to bone structure for machining and drilling aligned with the femoral head. In this context, the relation time c accuracy was very well explored, in order to assist with efficiency surgeons and patients requiring surgery that reduces the interference on the skill of the surgeon on the surgery outcome. The simultaneous development of the multilaminar-mill, designed to machine the femoral head matching the internal geometry of the resurfacing prosthesis is an important tool for reducing the surgery time, as the tool changes during surgery as shown this thesis. The surgical instrument responsible for the proper operation of these machining devices is a customized guide drill mark capable of aligning the drill and the mill during drilling and milling of the femoral head, according to the angle of the femoral neck of each patient. This work deals with the design, development and manufacturing of a machining device prototype and surgical instruments to promote the centralized machining following the angle of the femur neck the reduction of surgery time and the innovate arthroplasty surgery in humans animals. The products developed in this work are named as \"sequential multilaminar mill\", \"drilling centering mask\" and \"prosthesis and instrumental for dogs\", for hip resurfacing arthroplasty. With the developments, it is expected to reduce the surgical time, as well increasing safety, allowing greater success in these procedures.

Na prática clínica, a queixa de dor no joelho em pacientes, a partir da quinta década de vida, é muito freqüente e comumente atribuída à lesão meniscal degenerativa. A relação entre a lesão degenerativa do menisco e a artrose é controversa, assim como a relação do varo e a evolução para artrose do joelho. Foram estudadas as alterações macroscópicas e microscópicas dos meniscos em 21 pacientes com deformidade em varo submetidos a artroplastia total do joelho, decorrente de artrose do joelho. Analisou-se, também, a relação destas lesões com o grau de artrose e varismo dos pacientes. Foram encontrados 9 de 21 meniscos com lesões, sendo o menisco mais acometido o medial e a lesão mais freqüente em clivagem horizontal. Neste modelo clínico de artrose com joelho em varo, afirma-se que: 1) Não foi possível estabelecer correlação entre o grau de artrose e a maior ocorrência de lesões meniscais macroscópicas; 2) Não se observou relação entre a maior gravidade da deformidade angular em varo dos joelhos com o aumento da ocorrência de lesões meniscais; 3) Quando ocorreram, as lesões meniscais preponderaram no menisco medial e as mais freqüentes foram as em clivagem horizontal; 4) Os meniscos apresentaram alterações microscópicas significativas resultantes do processo de artrose dos joelhos; no entanto, não há evidência que a presença de lesões é estatisticamente diferente entre os meniscos lateral e medial / In clinical practice, the knee pain complaint by patients from the fifth life decade is very frequent and commonly assigned to degenerative meniscal injury. The relationship between degenerative meniscal injury and arthrosis is controversial, as well as the relationship between genu varum and evolution to knee arthrosis. Macroscopic and microscopic meniscal changes in 21 patients with varum deformities undergoing total knee arthroplasty secondary to knee arthrosis were also studied. The relationship between these injuries and the degree of arthrosis and varism of patients were also studied. Of 21 menisci, 9 were found to have injuries, the most affected being the medial meniscus and the most frequent was the horizontal cleavage meniscal injury. In this clinical model of arthrosis with varum knee (1) it was not possible to establish any correlation between the degree of arthrosis and the higher occurrence of macroscopic meniscal injuries; (2) no relationship was observed between higher severity of genu varum angular deformity and increase of meniscal injury occurrence; (3) meniscal injuries prevailed in the medial meniscus, horizontal cleavage meniscal injuries being the most frequent; (4) the menisci presented significant microscopic changes resulting from the knee arthrosis process; however, no evidence was found that the presence of injuries is statistically different between lateral and medial menisci

Este estudo objetivou avaliar o perfil clínico e epidemiológico de pacientes submetidos à cirurgia de prótese de quadril e que sofreram complicações relacionadas a esta no pós-operatório. A pesquisa foi realizada no período de 2002 a 2006; a amostra inicial foi composta de 398 cirurgias de pacientes submetidos à Artroplastia Primária de Quadril, realizadas em um hospital escola especializado da Cidade de São Paulo. Em 48 destas cirurgias ocorreram complicações pós-operatórias, compondo a amostra final deste estudo. Houve predominância de indivíduos do sexo feminino (66,7%), com média de idade de 59 anos, casados ou em união estável/amasiado (43,4%), provenientes da cidade de São Paulo (55,3%). Referente à escolaridade a maioria (58,1%) tinha fundamental completo. Quanto à ocupação houve predominância de aposentados e pacientes que desenvolvem atividades técnicas e ocupacionais, ambos com 35,1%. Infecção do quadril foi o motivo predominante para revisão da prótese de quadril (33,3%). A Vancomicina e a Ceftazidima, associadas, foram os antibióticos mais utilizados (58,1%). O estudo contribui para a estruturação de um cuidar multidisciplinar e especializado, pois possibilita o conhecimento da clientela, através de um perfil sociodemográfico e clínico, proporcionando mecanismos para intervenções de modo a transformar a assistência de Enfermagem em Ortopedia e Traumatologia e Reabilitação Física / This study was aimed at evaluating the clinical and epidemiological profile of patients submitted to hip prosthesis surgery who had complications related to it in the post-surgery period. The research was conducted between 2002 and 2006; the initial sample was comprised of 398 surgeries of patients submitted to Primary Hip Arthroplasty, performed at a specialized school hospital in the city of São Paulo. In 48 of those surgeries there were post-surgery complications, thus comprising the final sample of this study. There was a predominance of females (66.7%), with average age of 59, married or with a stable union (43.4%), living in the city of São Paulo (55.3%). Regarding education, most (58.1%) had finished primary school. As for occupation, the majority were retirees and patients that perform technical and occupational activities, both with 35.1%. Hip infection was the most common cause for hip prosthesis revision (33.3%). Vancomycin and ceftazydime, used together, were the most used antibiotics (58.1%). The study helps the development of a multidisciplinary, specialized care because it brings information about the clientele through a socio-demographic and clinical profile, thus providing mechanisms for interventions so as to transform care in Orthopedic and Traumatology Nursing and in Physical Rehabilitation Nursing

A verificação do trajeto do nervo isquiático por meio da dissecação da articulação coxofemoral de cadáveres da espécie canina, e a sintopia destas estruturas, tem relevância em ser pesquisada na medida em que tal relação neuroarticular pode estar envolvida nos casos de neuropraxia durante as intervenções cirúrgicas de artroplastia total do quadril de cães. O escopo do estudo foi o de apresentar uma contribuição aos cirurgiões em prendizado na implantação das próteses acetabular e femoral, para que possam compreender as relações anátomo-cirúrgicas entre a articulação coxofemoral e o nervo isquiático, e com a finalidade de potencializar positivamente o resultado do pós-operatório imediato dos cães. Foram utilizadas 20 articulações coxofemorais provenientes de 10 cadáveres de cães, com raças definidas ou SRD, machos ou fêmeas, com peso variável, sempre acima de 20 quilogramas, sem alterações macro-morfológicas nas referidas articulações, e dissecadas por técnica clássica. Realizou-se manobras de abdução articular para a obtenção de luxação articular, além da retração caudal do fêmur proximal, à semelhança do que ocorre no transcorrer da aplicação da técnica operatória de colocação da prótese total de quadril. A dissecação cirúrgica das estruturas estudadas revelou um aumento considerável de contato entre o nervo isquiático e a articulação coxofemoral durante as manobras de abdução articular em aproximadamente 90º, quando adicionada de retração caudal do femur proximal. Assim, conclui-se que a etapa ora referida, necessária pela técnica cirúrgica de artroplastia total de quadril em cães, pode levar a lesão do nervo isquiático, devendo o cirurgião estar atento na realização destas manobras. / The ischiatic nerve course verification using dissection of the hip joint from cadavers of the canine species, as well as the sintopy of these structures, have a relevant aspect to be investigated, because these neuro-articular relation can be involved in cases of neurapraxia during some surgical interventions of total hip arthroplasty in dogs. The main objective of the study was to present a contribution to the new surgeons during their learning phase of implantation of the acetabular and femoral prosthesis, so they can understand the anatomic and surgical relation between the hip joint and the ischiatic nerve, aiming to potentially make positive the immediate post surgical result of the treated dogs. 20 hip joints from 10 cadavers of dogs were utilized, with pure breeds or not, males or females, with variable weight, always over 20 kilos, without macro-morphological alterations in the hip joints, and dissected using the classical technique. Hip joint abduction manoeuvres were made to obtain the desired joint luxation, besides a caudal retraction of the proximal femur, like occurs during the application of the surgical technique utilized to perform the total hip replacement surgery. The surgical dissection involving the studied structures showed a significant increasing contact between the ischiatic nerve and the hip joint during the articular abduction manoeuvres, using approximately a 90 degree angle, and when added a caudal retraction of the proximal femur. Consequently, conclusion was that the above-mentioned stage, needed to perform the total hip arthroplasty procedure in dogs, can lead to a lesion of the ischiatic nerve. Thus, the surgeons shall be alert during the realization of these manoeuvres.

As progressivas inovações tecnológicas, na área de projeto mecânico, contribuem para a adoção de novos procedimentos cirúrgicos relacionados à ortopedia. Este trabalho trata do projeto, desenvolvimento e fabricação de dispositivos de usinagem e instrumentais cirúrgicos para aplicação em cirurgias de recapeamento da cabeça femoral em humanos e animais, buscando aperfeiçoar tal procedimento no que diz respeito a tecnologias voltadas à modelagem óssea e furação centralizada com a cabeça femoral. Nesse contexto, a relação tempo x precisão foi muito bem explorada, de forma a auxiliar com eficiência os cirurgiões e os pacientes que necessitam dessa cirurgia reduzindo a interferência da habilidade do cirurgião no resultado final da cirurgia. A fresa multilaminar sequencial, criada para usinar a cabeça femoral conforme geometria interna da prótese de recapeamento de quadril é uma importante ferramenta para redução do tempo de cirurgia, uma vez que é necessária a troca de ferramentas durante os procedimentos cirúrgicos como mostrado nesta tese. O instrumental cirúrgico, responsável para o funcionamento correto desses dispositivos de usinagem, é um guia de furação personalizado capaz de alinhar a broca e a fresa durante a modelagem da cabeça femoral, de acordo com o ângulo do colo femoral de cada paciente. Assim, este trabalho trata da concepção, desenvolvimento e fabricação de protótipos de um dispositivo de usinagem e instrumentais cirúrgicos que promovam a usinagem centralizada seguindo o ângulo do colo femoral, redução do tempo de cirurgia e da aplicação cirúrgica com prótese de recapeamento artroplastia de recapeamento canina. Os produtos desenvolvidos nesse trabalho serão nomeados como \"fresa multilaminar sequencial\", \"máscara para furação centralizada\" e \"prótese e instrumentais cirúrgicos para cães\", para a artroplastia de recapeamento de quadril. Com os desenvolvimentos, é esperada uma redução no tempo da cirurgia, bem como um aumento na segurança, possibilitando maior sucesso nesses procedimentos em humanos, bem como trás nova tecnologia para a medicina veterinária. / Progressive technological innovations in the area of mechanical design, contribute to the adoption of new surgical procedures related to orthopedics. This work addresses the design development and manufacture of machining devices and surgical instruments to be used in resurfacing surgeries of the femoral head in humans and animals, seeking to improve this procedure in regards to a new technology related to bone structure for machining and drilling aligned with the femoral head. In this context, the relation time c accuracy was very well explored, in order to assist with efficiency surgeons and patients requiring surgery that reduces the interference on the skill of the surgeon on the surgery outcome. The simultaneous development of the multilaminar-mill, designed to machine the femoral head matching the internal geometry of the resurfacing prosthesis is an important tool for reducing the surgery time, as the tool changes during surgery as shown this thesis. The surgical instrument responsible for the proper operation of these machining devices is a customized guide drill mark capable of aligning the drill and the mill during drilling and milling of the femoral head, according to the angle of the femoral neck of each patient. This work deals with the design, development and manufacturing of a machining device prototype and surgical instruments to promote the centralized machining following the angle of the femur neck the reduction of surgery time and the innovate arthroplasty surgery in humans animals. The products developed in this work are named as \"sequential multilaminar mill\", \"drilling centering mask\" and \"prosthesis and instrumental for dogs\", for hip resurfacing arthroplasty. With the developments, it is expected to reduce the surgical time, as well increasing safety, allowing greater success in these procedures.

Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are relatively new biomedical techniques developed during the last century, which are frequently recommended for patients with joint diseases. In spite of their success and huge popularity, the postoperative failure rates for these procedures remain significant. Migration and micromotion of the implant are the primary indicators of its postoperative stability and many in vitro measurement techniques have been discussed. However, effective, practical methods to measure these metrics in vivo have proven elusive and the evolution of such a technique is the subject of this thesis. An implantable, remotely interrogated electronic system for the in vivo measurement of both micromotion and migration in the axial direction is proposed. The main purpose of the device is to improve the ability of clinicians to assess the longterm stability of orthopaedic implants and also to plan and optimise patients’ rehabilitation protocols. The system is based on a modified form of differential variable reluctance transducer (DVRT) in which the nullpoint of the system set automatically by means of a selfcalibration process. Simulations and preliminary in vitro measurements on the bench show that the selfcalibration algorithm works correctly in spite of component tolerances and initial set up errors, allowing a gross displacement (migration) to be measured with a resolution of 15 �m and a range from 0 to 4 mm, and that the device can measure micromotion with an amplitude as low as 1 �m in the range from 200 �m to 200 �m. Accuracy of less than 10 % are achieved in both micromotion and migration measurements. Prototypes of all the major components and subsystems have been fabricated in CMOS integrated circuit (IC) technology as part of the project. Measurements support the feasibility of constructing an integrated version of the complete system for implantation and in vivo use in the future.