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Geomagic design x 2016 user guide pdf free
The new PMC design is here! Learn more about navigating our updated article layout. The PMC legacy view will also be available for a limited time. Federal government websites often end in. The site is secure. Data and materials are provide geomagic design x 2016 user guide pdf free requested, please contact author if applied. There is no universal hip implant suitably fills all femoral types, whether посетить страницу источник of porous short-stem suitable for Hip Arthroplasty is to be measured scientifically.
Then, these numerical models of Finite Element Analysis were exported to AnSys for numerical solution. Mechanically, these four sorts of artificial joint replacement are stabilized in quantity. How to install autodesk 2020 free preferred design of those two depends on clinical conditions.
The cemented long-stem is favorable geomagic design x 2016 user guide pdf free inactive elders with osteoporosis, and porously punched cementless short-stem design is suitable for patients with osteoporosis, while the porously punched cementless short-stem is favorable for those with a cement allergy.
Clinically, the strength of this study is to enable preoperative strategy to provide acute correction and decrease procedure time. A meticulous preoperative strategy is of paramount importance before performing a complex operation microsoft powerpoint 2019 crack free could employ multiple available reconstructive techniques. Additionally, proper modular implants of artificial prostheses in terms of type and length must be адрес страницы prior to hip surgery.
There are various procedures for treating femoral neck fractures. For fresh fracture without dislocation, internal fixation geomagic design x 2016 user guide pdf free preferable. For elderly patients with osteoarthritis or rheumatoid arthritis, Hip Arthroplasty HA is a prevalent approach to achieve function restoration of degenerative joint diseases in the twentieth century. The previous literature indicates that joint fracture is quite likely to occur if there are high stresses in the fixation areas [ 12 ], and conventional stems have showed на этой странице, such as proximal stress shielding, loss of bone stock, and a risk of fracture [ 3 ].
Dennis et al. Fawzi et al. Short-stem prostheses were reported primarily to preserve femoral bone stock, reduce the amount of osteotomy during femoral preparation and facilitate future revision surgery possibly [ 6 ], but there has been doubt that they can maintain stability, osseointegration and survival of the femoral stem [ 5 ]. Walker et al. Whiteside et al. Because uncemented straight stems have demonstrated excellent long-term results into the third decade, we hypothesize that the stem type or size may geomagic design x 2016 user guide pdf free the value and distribution of mechanical stress, but newly designed short-stem designs need to be critically evaluated.
To realize this aim, first of all, a three-dimensional 3D femoral model for preoperative planning is achieved by Reverse Engineering Software that mimicked operative protocol virtually; then, four sorts of simulative stems Cemented stem of long and short without pore, Cementless stem of long and short with pore were designed and compared by Finite Element FE method mechanically.
Finally, clinical contention concerning the bio-mechanism is discussed in the conclusion. Ten femora scanned by CT in Dicom format were exported to Mimics. NURBS kyrtograph fitted for femoral shafts. Simulative osteotomy occurred on Geomagic-studio along the break-angle посмотреть больше prosthesis by same direction.
The remaining prosthetic stem, which was amplified by 2 voxels, was imported onto UG to fit 3D-solid model. The models were then exported to Hypermesh to remove the original prosthetic stem from the amplified prosthetic stem by Boolean calculation. The virtual model of the bony cement layer with 3 mm-thickness [ 10 ] and a cavity are shown in Fig. The above models of the femora, prostheses and cement were synthetized in Hypermesh to assemble the following four replacement types: a long-stem cemented prosthesis Fig.
A distal femur can be obtained after removing the space occupied by the prosthetic cemented stem or porous stem by Boolean calculation. The femora and other compartments were volume-meshed with cell-attribute assignment. All models of femora, prostheses and cement were exported back into Mimics for materials assignment. Then, the elastic modulus geomagic design x 2016 user guide pdf free automatically calculated. The properties of the remaining materials are based on prior studies [ 1112 ].
In this way, the geometrical 3D FE models of classic stems were obtained. The above grid models are to be imported back to Hypermesh so that a compressive geomagic design x 2016 user guide pdf free of N was applied vertically and applied on the bone structures symmetrically. The degree of freedom on a node basis of x-y-z direction of Cartesian coordinate was constrained to 0, and translational displacements at the distal nodes of the femur were inhibited Fig.
Verification of model validity. Its validity will be verified by comparing the similarity of outcomes for each experiment based on equal status.
On the other hand, strain-foils were attached at relative positions of an intact cadaveric femur corresponding to FE нажмите для деталей and mounted to UTM [ 12 ] Fig. The load-strain curve was observed by recording the strain value when the maximal pressure of N was reached. This generated FE model was exported onto AnSys package for computation and analysis, and the peak and distribution yield конечно, free quarkxpress 10 full version for mac free интересно measured.
The current testing outcome was consistent with the validation technique and study conducted by Zhang et al. As depicted by Fig. For model athe pressure crest value is across the edge of femoral-head intersecting the prosthetic stem. For style bthe summit value is along the middle of prosthetic stem. For style cthe stress peak appears at the intersection of prosthetic terminus and bony cement.
For style dthe stress apex is located at prosthetic head crossing neck as well as the middle stem. The prostheses are easier to damage from these locations [ 18 ]. By reviewing the Von Mises variation of FEA data, the reaction stresses of femora are distributing equally inferior to femoral trochanter and superior to the constrained position. Additionally, stress peaks disperse around the interface of the prostheses terminus and femur.
Based on the Von Mises outcome, the contact stresses of any type of integral joint distributed similarly as the prostheses, the stresses peaked on the prostheses and decreased from the maximum value at the femoral fixation point to the minimum values at the proximal end. Geomagic design x 2016 user guide pdf free, the a cemented long-stem and d porous short-stem are the least geomagic design x 2016 user guide pdf free.
Femur displacement implies its magnitude of stability relative to femoral joint. Through observation of Fig. The direction of migration was vertical downward. The displacement of integral joint implies its magnitude of fastness relative to the entire femoral joint.
By observation of finite element data, we found that the direction of displacement was vertically downwards, the all peak displacements were concentrated on the head of prostheses and decrease distally in concentric circles. The distribution of prosthetic displacement behaves similarly to that of the integral joint. Artificial short stems for uncemented total HA have been alternatively practiced to conventional stem designs.
However, there is little biomechanical examination for effects of stem length and stem character on surgical complications [ 20 ].
To isolate clinical variables, the theoretic test performed by FEA is essential to Mimic ultimate prosthetic geometry prior to actual fabrication because it is rectified to fail practically if a stem fails at this stage. Computational FEM has been extensively employed in predicting optimized implants prescribed by surgeons [ 21 ]. The strength of FEA carried out by computer aided simulation enables geomagic design x 2016 user guide pdf free strategy and decreases procedure time.
Our models were not only consistent with predecessors, and they were also similar to cadaveric data. These punched prostheses were designed virtually with mechanic compatibility and bio-compatibility for clinical application.
These structures may induce bony geomagic design x 2016 user guide pdf free at the porous interface, which is beneficial to bioactivity. Additionally, all the four femoral stems were anatomically tailored to individualize the femoral structure towards stress and displacement.
Displacement is an indicator for determining the stability of newly designed stems. Several factors such as implant shape, stem size, bone-implant gap are accounted for micromotion [ 22 ].
Regarding cemented stems, fastness between bone and cement relies on penetration of the cement upon cortex. The mechanical interlocking between these two constituents is correlated with bony stress surrounding the cement. A Load-transfer mechanism takes place at this interface, and cementing mechanization is driven by friction rather than adhesive properties [ 23 ].
Previous studies indicate that the amount of ongrowth is inversely proportional to the amount of micromotion [ 24 ]. With respect to porous stems, Manley et al. At this time, we numerically demonstrated the degree of stabilization using the analytical FE approach. Pre-stress to bones can be created in femoral canal by internal fixation, which is probably susceptible to failure based on the stresses distribution onto the modular junctions of the implants.
Suppose the joint with implant is loaded in equivalency. There are several possible mechanical reasons for these outcomes: 1If designed with cemented, when considering the stem, because quota-stress is shared by wider area when length is extended, stress on long-stem is less than short-stem. When considering the cement, which is the weakest material and has a higher risk of fatigue failure at the cement-bone interface, maximum stress on the cement increases when the length increases, a longer distance between the loading-point and fixation-point induces larger bending-stress at the distal end.
The porous nature enables bony ingrowth, and the new bones can handle load and enlarge surface area [ 28 ]. As a result, stress on cementless-stem with pore is sequentially less than cemented-stem without porous coating geomagic design x 2016 user guide pdf free 429 ].
Therefore, short-stemmed punched-prostheses are generally thought to facilitate surgery compared to long-stemmed cemented-prostheses. The prostheses inserted into the femoral cavity might change the normal stresses distributions. Stress can be /23261.txt to the distal femur via intramedullary prosthesis despite its support by the proximal femur, which leads to stress-shielding, affecting the osseous integrity and resistance [ 30 ].
Longer stems are believed to give higher stresses at the femur and then be capable of geomagic design x 2016 user guide pdf free stress shielding problems, whereas shorter stems decrease основываясь на этих данных load-transfer to the cortical bone and encourages stress shielding and bone resorption, which results in failure of the prosthesis sometimes [ 31 ].
Chen WP et al. For an uncemented short stem, even if Maier reported it is curved stems but not straight stems that cause cortical hypertrophy, there is no significant effect on the clinical outcome at early follow-up [ 33 ]. Regarding porous prostheses, Ellison et al. As another result, the module that achieves the minimum stress-shielding is the cementless prosthesis, due to poor results of cemented components after revision surgery, short-stem of porously punched uncemented prosthesis has become more popular.
In summary, this study proposes long v. The data support the hypothesis that stresses and distributions of prosthetic stems are various from types or sizes: Mechanically, displacement outcome has equal fastness for these four types of femoral stems, and the mechanic result is positive for both cemented long-stem and uncemented short-stem designs. Clinically, the cemented long-stem design is suitable for patients with osteoporosis, while the porously punched cementless short-stem is preferable for those кажется adobe premiere pro cs6 highly compressed 10mb free ответ easy osseo-ingrowth or with cement allergy.
Functionally, the advantage of the punched-prosthesis designed by virtual computation without a cement matrix is that it could be immobilized by the flesh bone structure growing inside the prosthesis orifices. Not only is the contract stress reduced, complications in cement are also avoidable, and this approach should be recommended as reasonable alternative for femoral-head replacement.
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