Objetivo: comparar fixação transversa de enxertos tendinosos solidarizados versus não-solidarizados e entre duas posições rotacionais diferindo 90 graus entre si em túnel ósseo. Métodos: trinta e seis sistemas de fixação de tendões quádruplos bovinos em osso porcino foram confeccionados e divididos em quatro grupos de acordo com duas posições rotacionais de enxerto (diferindo 90◦) e presença ou não de solidarização. Em ensaio de tração, os dados de força e deslocamento nos pontos de falha (força máxima Fmax e primeiro pico válido Fp) e ponto de medida 445N foram medidos, comparados e utilizados para o cálculo de rigidez. Foram contabilizados os picos intermediários válidos. Resultados: os grupos “à cavaleiro” apresentaram maior força de ponto de falha com todos os parâmetros (p < 0,05) e maior rigidez com o uso de ponto de força máxima (P < 0,05). Nos grupos transfixantes, o grupo com solidarização apresentou maior Fmax e Fp (Fmax de 1555,4N ± 408 versus 1135,2 ± 448,7, Fp de 1539,9N ± 400,8 versus 950,5N ± 599,8). A quantidade de picos intermediários foi maior no grupo transfixante sem solidarização. Conclusão: A posição “à cavaleiro” apresentou maior Fmax, Fp e rigidez. Com a solidarização, o grupo transfixante obteve melhor resposta à tração. / Purpose: To make comparison between sewed and not sewed and between two different rotational positions of transverse fixed tendon graft inside bone tunnel. Methods: Thirty-six quadrupled bovine tendon grafts fixation systems in porcine femurs models were divided into four groups concerning rotational positioning inside de bone tunnel and the presence of sewing through the tendon sections. By measuring displacement and load at the resistance limit, first validated peak and 445N point, the groups were compared and the rigidity was achieved. The intermediate validated peaks were observed. Results: looped positioned groups showed higher fail points levels than the transfixed groups using all parameters (p<0,05), as well as greater rigidity when using the maximum load as fail parameter. In transfixed tendons groups, the sewed tendon group showed greater Fmax and Fp (Fmax 1555,4N ± 408 versus 1135,2N ± 448,7 and Fp 1539,9N ± 400,8 versus 950,5N ± 599,8), p<0,05. Intermediate peaks incidence was greater in the not-sewed/not-looped (transfixed) group Conclusion: looped positioned group gave better results: greater Fmax, Fp, and rigidity. The transfixed tendons group had better response to tensile load when sewed.

O estudo fez comparações entre a intensidade e a distribuição das deformações a que fica submetido o fêmur proximal intacto e o fêmur proximal fraturado e implantado com o sistema parafuso deslizante Dynamic Hip Screw – DHS, em fraturas transtrocantéricas do tipo 31 - A2 – 2. Para isso, foram produzidas deformações, mediante carregamentos cíclicos, em fadiga. As amostras constituíram-se de ossos de fêmur sintéticos, intactos, e de ossos de fêmur sintéticos onde foram feitos cortes em laboratório produzindo situações de fratura do tipo 31 –A2.2. Nas amostras fraturadas foram colocadas as placas DHS simulando situações reais de osteossíntese. Os conjuntos de ossos mais placas foram então submetidos a ensaios de fadiga. Os resultados demonstraram que as presenças da fratura e do implante DHS alteraram a amplitude das deformações em todas as regiões do fêmur. Houve absorção da carga pelo implante DHS em todas as regiões de medição. Na região do colo femoral, o DHS absorveu 98% da carga, na região lateral 97%, no centro medial transversal 48%, no centro medial longitudinal 92%, no centro medial a 45 graus 94%, no calcar, antes da linha da fratura, 80%, na região do calcar, depois da linha da fratura, 81%, na região do segundo parafuso cortical transversal 81%, na região do segundo parafuso cortical longitudinal 73% e na região do segundo parafuso cortical a 45 graus 92%. A região do centro do pino guia e a região do segundo parafuso cortical foram as regiões de maior instabilidade mecânica. Para as condições de fratura do tipo 31 – A2.2 o implante do tipo DHS não absorve totalmente as deformações geradas, apresentando mobilidade do foco da fratura. Pequenas oscilações entre os ensaios causaram modificações importantes nos resultados, indicando que a relação ponto de medição ou a posição exata do implante podem implicar num desgaste ou afrouxamento prematuro do mesmo devido a uma sobrecarga. / The study compared the intensity and distribution of the deformations to the intact proximal femur and the proximal femur fractured and implanted with the slide screw system, Dynamic Hip Screw – DHS, in transtrochanteric fractures, 31 – A2 – 2 type. In this way, deformations were produced, by means of cyclic loads, in fatigue. The samples consisted of synthetic femoral bones intact and synthetic femoral bones that were cut in the laboratory producing fracture situations of type 31 – A2.2 type. In the fractured samples the DHS plates were placed simulating real osteosynthesis situations. The bone sets and plaques were then subjected to fatigue testing. The results showed that the presence of fracture and DHS implant altered the amplitude of deformations in all regions of the femur. The load was absorbed by the DHS implant in all measurement regions. In the femoral neck region, DHS absorbed 98% of the load, in the lateral region 97%, in the medial center – transverse – 48%, in the medial center – longitudinal – 92%, in the medial center – 45 degrees – 94%, in the calcar region, before the fracture line 80%, in the calcar region, after the fracture line, 81%, in the region of the second cortical screw – transverse – 81%, in the region of the second cortical screw – longitudinal – 73% and in the region of the second cortical screw – 45 degrees – 92% . The region of the center of the guide pin and the region of the second cortical screw were the regions of greater mechanical instability. For fracture conditions of type 31 - A2.2, the DHS type implant does not totally absorb the generated deformations, presenting mobility of the fracture focus. Small oscillations between the tests caused significant changes in the results, indicating that the relationship between the point of measurement and the exact position of the implant may lead to premature wear or loosening of the implant due to an overload.

Different tracing techniques of the subperiosteal and endosteal contours (manual, automatic, semi-automatic) or their combinations taken along femoral length in adult individuals can produce different values of cross-sectional geometric (CSG) parameters. Various tracing techniques are widely used in CSG studies of non-adult individuals as well, however, the accuracy of CSG parameters estimated along femoral diaphysis is not yet known for non-adult individuals. In this study, we investigate whether the manual tracing of the subperiosteal and endosteal contours taken at 80% of the femoral diaphyseal length in non-adult individuals can be replaced by another type of tracing in relation to CSG parameters estimation. We examine the effect of anatomical localization on accuracy of the CSG parameters estimated in non-adult individuals femora. We digitized the subperiosteal and endosteal contours in the micro-CT scans from femoral diaphyseal cross-sections in Early Medieval sample of non-adult individuals (N = 46). The digitization and computation of CSG parameters were made in Fiji software with EPJMacro implementation. The assessment of estimates' accuracy was expressed by percentage prediction error (%PE) and limits of agreement. Five percent of CSG parameter obtained from manually traced contours was...

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This work is focused on a solving of problems regarding a total hip replacement with a fractured femur. The fracture is located in the distal end of the total joint replacement stem and the fracture is spreading in the proximal direction on the boundary of the bone and cement. A proximal part of femur is reinforced by fixing tape. There is also briefly described how computer models were carried out. Furthermore a stress - strain analysis of solved system has been performed in this work. The solution was realized using the finite element method in computational program ANSYS Workbench. Different variants with change of a fracture range and number of fixing tapes were considered during the solving. Stress - strain analysis shows that due a application of fourth fixing tape occurs lowering of main stresses values in the femur in fracture region. Simultaneously occurs a reduction of Equivalent stress values on a distal part of stem.

This master´s thesis consists of three relief objects composed from femur bones. The first relief object is geodetic structure applied to the shape of a sphere. The following two are deformed by softening the material from which they are cast. The second relief object also works with geometry (a square at the base) and systematic folding bones according to a clear order. The third relief can directly interfere with the viewer - the individual femurs contain every two magnets and therefore can move freely with them after the metal plate.

Dans le but d’enrichir la modélisation virtuelle d’êtres humains et de mieux comprendre la biomécanique de certaines parties du squelette, ce travail propose une analyse comparative des propriétés histologiques et mécaniques de deux os appendiculaires fonctionnellement opposés : l’humérus et le fémur. La campagne a été réalisée à partir d’échantillons provenant de quatre SHPM embaumés (Sujet Humain Post-Mortem), de sexe masculin. Une étude géométrique en 3D a débuté l’expérimentation. Elle a été suivie par une analyse histomorphométrique de 153 photographies réalisées à partir de la face antéromédiale du cortex diaphysaire, à quatre niveaux de hauteur et à trois niveaux de profondeur. Des essais mécaniques ont ensuite été effectués sur 28 éprouvettes d’os cortical non congelé, provenant du même site anatomique. L’expérimentation s’est déroulée sur machine conventionnelle de traction. Elle comportait des essais en traction/compression et des essais de cyclage en traction dans le domaine élastique, à la vitesse de 0,05 mm/mn, jusqu’à rupture. Une loi d’endommagement a également été élaborée. Ces travaux ont montré que ces deux os offrent un comportement différent. L’humérus s’avère être moins résistant et plus raide que le fémur. Son endommagement intervient plus rapidement. Les valeurs mécaniques relevées sont en rapport avec la densité et la taille des ostéones actifs, ainsi qu’avec les caractéristiques de la porosité Haversienne. Les différences de comportement mécanique relevées s’expliquent par l’adaptation microscopique du tissu osseux cortical aux contraintes subies par un os porteur ou non-porteur. Les variations interindividuelles observées sont fonction de son état physiologique. / With the aim of enriching the virtual modelisation of human beings and understanding better the biomechanics of some parts of the skeleton, this work proposes a comparative analysis of histological and mechanical attributes of two functionally opposed appendicular bones: femur and humerus. The campaign has been done with samples coming from four embalmed PMHS (post mortem human subjects) of the male gender. A 3D geometric study started the experiment. It was followed by an histomorphometric analysis of 153 pictures carried out on the anteromedial face of the diaphyseal cortex at four levels of height and three levels of depth. Mechanical tests were then done on 28 specimens of non frozen cortical bone coming from the same anatomic site. The experiment took place on a conventional traction machine. It consisted of traction/compression tests and cycling tests under traction in the elastic zone, at the speed of 0.05 mm/mn until yield point. A damage law has also been elaborated. These studies have shown that these two bones offer a different behaviour. The humerus bone turns out to be less resistant and stiffer than the femur. It is damaged more quickly. The mechanical values noted are related to the density and the size of active osteons and also to the characteristics of Haversian porosity. The difference of mechanical behavior noticed can be explained by the microscopic adaptation of the cortical bone tissue to the stresses undergone by the bearing and non bearing bones. The inter-individual variations observed are linked to the physiological state of this tissue.

Introduction: Fractures of the proximal end of the femur are one of the most frequent diagnoses. Patients with this diagnosis have to deal with performing daily activities. Both for painas well for the necessity of adherence to antiluxal measures. Thanks to this decrease thein independence from the other person. As one of the maingoals in this diploma thesis we determined means how occupational therapy canincrease self - sufficiency in this target group. As other goals, we found in formativ about the selection and financing of compensatory aids and we made a manual about this information. We focused on the factors that affect the return of patients to the home environment. Methodology: In the personal parts we chose 6 case studies (3 men and 3 women), in the averageage 73.5 years (median 72, 5), youngest 64 years, oldest 85 years. Patients underwent 5 therapies dedicated to the training of self - sufficiency of personal everyday activities (pADL). We measured the effectiveness of th erapeutic units using the Barthel Index. We observed them and found out chat compensatory aids they use for self-sufficiency Results: Probands recese daverage 33.3 points in the evaluationat the initialexamination. After graduating therapiest heave rage performance of all probands obtained at 67, 5 points. They used...

In the pool of women over the age of 50, the likeliness of an atypical fracture increase drastically, partly due to osteoporosis. With a pre-existing implant in the femur bone, inserted due to a prior atypical fracture, treating a later femoral neck fracture is complex and risky. Currently, a fractured femoral diaphysis is treated using an intermedullary nail which is fixed to the femur bone either through the femoral neck (Recon locking method)or through the lesser trochanter (Antegrade locking method). In a study conducted by Bögl et.al. JBJS102.17 (2020), pp. 1486-1494, it is found that the fixation of the intermedullary nail through the femoral neck reduces the risk of future femoral neck fractures. The study also states that more than 50% of the patients with atypical femoral fractures related to bisphosphonate treatment for osteoporosis (within the study sub population) were treated with the Antegrade locking implant. There does not exist much literature that reasons as to how one locking method is showing lesser risk of re-operation as compared to the other. The purpose of this study is to look into the effects these two implants have on the femur bone using the Finite Element Analysis (FEA). The study presented is aimed at comparing the results of the finite element analysis for the Recon implant model (Recon model) and Antegrade implant model (Antegrade model). The femur model without the implants (native bone model) is used to verify material behavior, while the other two are used for the comparison to study the stress-strain distribution, primarily in the neck region. This is a patient specific study, hence the femur bone model is generated using patient Computed Tomography (CT) scans. The bone model was assigned a heterogeneous isotropic material property derived from patient CT data. The finite element (FE) model of the bone was meshed using Hypermesh. The peak loading condition including the muscle forces were applied on the native bone model along with the Recon and the Antegrademodel. While the loading conditions during normal walking cycle were only applied to theRecon and the Antegrade model to compare the impacts of the two implant types. Both loading conditions were simulated by fixing the distal condyle region of the bone. The analysis results show that the Antegrade implant experiences much higher stresses and strains in the neck region as compared to Recon implant. Also, the presence of the intermedullary nail through the femur diaphysis helps to distribute the stresses and strains in the anterior distal diaphysis region of the bone. For the case of no implants, the model showed strains and stresses in the lateral distal region of femoral diaphysis.

The femur is the longest limb bone found in humans. Almost all the long limb bones found in terrestrial mammals, including the femur studied herein, have been observed to be loaded in bending and are curved longitudinally. The curvature in these long bones increases the bending stress developed in the bone, potentially reducing the bone’s load carrying capacity, i.e. its mechanical strength. Therefore, bone curvature poses a paradox in terms of the mechanical function of long limb bones. The aim of this study is to investigate and explain the role of longitudinal bone curvature in the design of long bones. In particular, it has been hypothesized that curvature of long bones results in a trade-off between the bone’s mechanical strength and its bending predictability. This thesis employs finite element analysis of human femora to address this issue. Simplified human femora with different curvatures were modeled and analyzed using ANSYS Workbench finite element analysis software. The results obtained are compared between different curvatures including a straight bone. We examined how the bone curvature affects the bending predictability and load carrying capacity of bones. Results were post processed to yield probability density functions (PDFs) for circumferential location of maximum equivalent stress for various bone curvatures to assess the bending predictability of bones. To validate our findings on the geometrically simplified ANSYS Workbench femur models, a digitally reconstructed femur model from a CT scan of a real human femur was employed. For this model we performed finite element analysis in the FEA tool, Strand7, executing multiple simulations for different load cases. The results from the CT scanned femur model and those from the CAD femur model were then compared. We found general agreement in trends but some quantitative differences most likely due to the geometric differences between the digitally reconstructed femur model and the simplified CAD models. As postulated by others, our results support the hypothesis that the bone curvature is a trade-off between the bone strength and its bending predictability. Bone curvature increases bending predictability at the expense of load carrying capacity.