Rozprawy doktorskie: „Artificial hip joints”

1

Schumacher, Brian. "An analysis of the femoral head/stem taper lock for orthopaedic prostheses". Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/18927.

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2

Walter, William Lindsay School of Biomechanics UNSW. "Severe biomechanical conditions in total hip replacement". Awarded by:University of New South Wales. School of Biomechanics, 2006. http://handle.unsw.edu.au/1959.4/25968.

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Hip simulators are designed to reproduce the forces and motion patterns of normal walking. In vivo demands on total hip replacements, however, are varied and often more severe than normal walking conditions. It is these severe conditions that often lead to implant failure. This is clinically based research aimed at understanding some of the more severe conditions in hips and the effect that these have on the performance of the total hip replacement. The polyethylene liner can act as a pump in an acetabular component, forcing fluid and wear particles through the holes to the retroacetabular bone causing osteolysis. Ten patients were studied at revision surgery. Pressures were measured in retroacetabular osteolytic lesions while performing pumping manouvers with the hip. Two laboratory experiments were then designed to study pumping mechanisms in vitro. In patients with contained osteolytic lesions, fluid pressure fluctuations could be measured in the lesion in association with the pumping action. Patients with uncontained osteolytic lesions showed no such pressure fluctuations. In the laboratory we identified 3 distinct mechanisms whereby fluid can be pumped from the hip joint to the retroacetabular bone. These pumping effects could be mitigated by improved implant design. Loading of the femoral head against the edge of the acetabular component produces dramatically increased contact pressures particularly in hard-on-hard bearings. In an analysis of 16 retrieved ceramic-on-ceramic bearings we were able to characterise the mechanism of edge loading based on the pattern of edge loading wear on the bearing surface. Finally in a radiographic study of patients with squeaking ceramic-on-ceramic hips. Squeaking was found to be associated with acetabular component malposition. It seems that edge loading or impingement may be an associated factor in these cases.

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3

Li, Junyan. "Computational biomechanics/biotribological modelling of natural and artificial hip joints". Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5500/.

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The excellent hip function and potential degeneration are closely linked with the unique structure of the joint cartilage that is principally composed of a solid phase and a fluid phase. Once damaged, the joint may need to be replaced by prosthesis in order to restore function in hip kinematics and kinetics. However, to what extent this can be achieved has yet to be quantified. On the other hand, the role of fluid pressurisation which plays in hip function has been poorly understood. The aim of this thesis was to address these issues. To evaluate the gait abnormality, particularly in terms of hip contact forces, a musculoskeletal model of lower extremity was constructed in a rigid-body dynamics frame, and the hip kinematics and kinetics were determined and cross-compared for a group of asymptomatic total hip replacement (THR) patients, THR patients with symptoms of symptomatic leg length inequality (LLI) and normal healthy people. Significant abnormal patterns in gait kinetics were observed for the asymptomatic THR patients, and this abnormality was greater for the LLI patients. To understand contact mechanics and the associated fluid pressurisation within the hip cartilage, a three dimensional finite element (FE) hip model with biphasic cartilage layers were developed. The protocol was compared to other solvers. A set of sensitivity studies were undertaken to evaluate the influence of model parameters, and then the model was evaluated under a range of loads with different activities. In all the cases, the fluid supported over 90% of the load for a prolonged period, potentially providing excellent hip function and lubrication. The musculoskeletal model and FE joint were combined to investigate the performance of the non-operated joint of the THR / LLI patients during gait which was found to function in a mechanically abnormal but not adverse environment. Lastly, the methodology of the biphasic hip modelling was validated using an experimental porcine hip of hemiarthroplasty. Good agreement was achieved between the FE predictions and the experimental measurement of the contact area.

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4

Kohm, Andrew Christopher. "New techniques for characterization of surface and volumetric wear in total hip athroplasty". Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1070378403.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xii, 173 p.; also includes graphics Includes bibliographical references (p. 170-173). Available online via OhioLINK's ETD Center

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5

Dyrkacz, Richard Michael Ryan. "Corrosion at the head-neck taper interface of artificial hip joints". Journal of Arthroplasty, 2013. http://hdl.handle.net/1993/30545.

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The aim of this thesis was to determine if the size of the femoral head can influ-ence corrosion at the head-neck taper interface of total hip arthroplasty (THA) prosthe-ses. A hypothesis was developed that large head sizes could result in a greater toggling torque at the head-neck taper interface by increasing the distance between the centre of the femoral head to the centre of the neck taper. This could result in increased micromotion and deteriorate the passive oxide film along the head-neck taper interface; thus, making the taper interface vulnerable to corrosion. A retrieval analysis of 74 THA prostheses studied the corrosion damage at the head-neck taper interface. This study revealed that prostheses featuring 36 mm femoral heads had significantly greater head taper corrosion than prostheses with a 28 mm head. Finite element analysis was performed afterwards to identify if the use of large femoral heads can increase the micromotion at the head-neck taper interface due to a greater toggling torque. This experiment demonstrated that with a larger head size the micromotion at the head-neck taper interface increases. An in vitro corrosion fatigue study was performed afterwards following ASTM F1875-98. When applying an off-axis fatigue load, prostheses featuring a 36 mm femoral head displayed significantly more corrosion damage at the head-neck taper interface than those with a 28 mm femoral head. Axial fatigue loading was also applied; negligible corrosion damage at the head-neck taper interface was discovered in comparison to the prostheses that received an out of axis load. This verifies that the use of large femoral heads can result in increased head-neck taper corrosion due to a greater toggling torque.

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6

Ramjee, Shatish. "Numerical analysis of lubrication in an artificial hip joint". Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-09152008-133304/.

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7

Walker, David. "Wear of alumina-on-alumina hip prostheses : indentation, fatigue". Thesis, The University of Sydney, 1996. https://hdl.handle.net/2123/27592.

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A compressive fatigue testing apparatus was constructed and used to model the wear of alumina-on-alumina hip prostheses via asperity contact. A ball indenter was used to indent flat alumina specimens which has similar mechanical properties, and initial contact stress versus the number of cycles until wear initiation or to gross wear were plotted for two different grainsized aluminas.

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8

Wu, Jun Jie. "The integrity of moulded ultra-high molecular weight polyethylene for joint replacement prostheses". Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325574.

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9

Ganguli, Arunima. "The interaction of bisphosphonates in solution and as coatings on hydroxyapatite with osteoblasts and macrophages". Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248739.

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10

Miles, Brad. "Reducing the risk of peri-prosthetic femoral fracture : prothesis, patient or procedure?" Phd thesis, Faculty of Engineering and Information Technologies, 2012. http://hdl.handle.net/2123/9987.

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11

Opperman, Tertius. "Tribological evaluation of joint fluid and the development of a synthetic lubricant for use in hip joint simulators". Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-07282005-083909.

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12

Bastidos, Amanda Marie. "Failure analysis and materials characterization of hip implants". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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13

Hustosky, Keith T. "Experimental characterization of the mechanical consequences of a debonded total hip stem with an unsupported distal tip". Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2510.

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Thesis (Ph. D.)--West Virginia University, 2002.
Title from document title page. Document formatted into pages; contains xi, 95 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 85-92).

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14

Wang, Allan W. "Femoral bone remodelling following cemented hip arthroplasty in a sheep model /". Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phw2462.pdf.

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15

Önsten, Ingemar. "Fixation of total hip components in rheumatoid arthritis and srthrosis a radiographic, roentgen stereophotogrammetric, densitometric and histomorphometric study /". Lund : Dept. of Orthopaedics, University of Lund, Malmö General Hospital, 1994. http://books.google.com/books?id=mGVsAAAAMAAJ.

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16

Ren, Ying [Verfasser]. "Diamond-like carbon coatings deposited by vacuum arc in artificial hip joints / Ying Ren". Wuppertal : Universitätsbibliothek Wuppertal, 2013. http://d-nb.info/1045118397/34.

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17

Groome, Isabelle Marie-Clement. "Finite element analysis of stress in prosthesis implanted canine femur". Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/16990.

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18

Farrar, Richard. "Simulation and analysis of the wear of metal on metal articulations in artificial hip joints". Thesis, University of Leeds, 2001. http://etheses.whiterose.ac.uk/4397/.

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Metal on metal articulations used in hip joint replacement were demonstratedth rough the 1960's and 70's to perform adequately and comparably to metal on plastic articulations but their use then fell into decline as orthopaedic surgeons preferred metal on polyethylene articulations. However, one of the main causes of failure of prosthetic hip joints was then discovered to be aseptic loosening due to particle induced osteolysis, such particles arising from wear of the prosthetic components, and in particular from polyethylene bearing surfaces. Through the late 1980's and the 1990's the concept of metal on metal bearings has re-emerged as one potential solution to the clinical problems associated with polyethylene particle induced osteolysis. In this thesis both theoretical analysis and practical testing using a 12 station MMED hip joint simulator were employed to investigate how metal on metal articulations may be optimized so as to reducet he amount of wear debris generatedth rough their use. Hence, such articulations should function effectively within the environment of a human hip joint when they form part of a total hip replacement design. To this end the effect of diametral clearance, head size, and material composition were both tested and analyzed. Finally a modular clinical design of hip joint replacemenwt as tested to assess its performance. Wear was found to be strongly related to bearing clearance in practical tests as predicted by the theory. A lower limit of clearance existed due to deviations from perfect form which were unavoidable with current manufacturing technology. A band of clearance was defined for 22, 28, and 35mm diameter bearings within which reduced wear was exhibited. Steady state wear rates, following the initial bedding in period, were generally equal regardless of total wear volume. High carbon against high carbon content cobalt chromium articulations did not produce the lowest wear contrary to previous studies in the literature. The mean hardness of, and hardness difference between, bearing surfaces influenced the wear performance of metal on metal articulations. It was possible to design a clinical metal on metal bearing having modular femoral (head and stem) and acetabular (insert and shell) components with optimized metal on metal articulation. This metal on metal device has been introduced into clinical use throughout the world.

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19

Bruton, Allison Renee. "Manufacturing and performance of titanium dioxide-ultra high molecular weight polyethylene nanocomposite materials". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 175 p, 2007. http://proquest.umi.com/pqdweb?did=1251905071&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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20

Meng, Qingen. "Elastohyrodynamic lubrication in metal-on-metal artificial hip joints with aspherical bearing surfaces and complex structures". Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535667.

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21

Park, Hyuen Me (Mia) Park. "Numerical and experimental analysis of stress behavior of plasma-sprayed Bioglass on titanium /". Full text open access at:, 1996. http://content.ohsu.edu/u?/etd,587.

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22

Thyagarajan, Ganesh. "Three-dimensional finite element modeling of total hip arthroplasty--creep under dynamic load". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1934.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains ix, 80 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 75-80).

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23

Kinney, Timothy. "A comparison of modeling techniques using the finite element method to determine local displacements in a human hip /". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5987.

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Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 14, 2008) Includes bibliographical references.

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24

Spirakis, Athanasios Apostolou. "A qualitative holographic study of hemipelvic and acetabular deformation caused by different hip prostheses". Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/25792.

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Aseptic loosening of the components is probably the most common long-term complication resulting in failure of Total Hip Arthroplasty. The mechanical behaviour of bone under load is one of the contributory causes of loosening encountered at the prosthesis/cement/bone interface. The present study dealt with a series of invitro experiments conducted on epoxy resin models of human hemi-pelves with different commercially available acetabular components implanted in them. These are used for the construction of simplified models of the artificial hip joint (three-dimensional) and of the prosthesis/cement/bone acetabular interface (two-dimensional). Loading conditions for the models included tensioning of the simulated abductor muscles for the hemi-pelvic and femoral loading for the prosthesis/cement/bone interface study. The experimental method employed was real-time holographic interferometry, a stress analysis technique recently used in the biomechanical field, which permitted whole-field simultaneously inspection of deformation patterns. The holographic interferograms were interpreted in a qualitative rather than a quantitative manner. The models do not exactly represent the in-vivo situation. Since this study identified high stresses both in the hip bone as well as in the interface (prosthesis/bone) it is suggested that these stresses are implicated in the mechanical pathogenesis of loosening. The observed changes in stress levels detected in our models could serve as a guide for future designs of acetabular prostheses as well as guide a in surgical techniques.

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25

Burger, Nicolaas Daniel Lombard. "Failure analysis of ultra-high molecular weight polyethyelene acetabular cups". Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-12142006-134036.

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26

Brumby, Scott Andrew. "The effect of surface roughness and a collar on fixation of cemented femoral stems in vivo /". Title page, table of contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phb8934.pdf.

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27

Feldt, Christian E. "Stress shielding minimized in femoral hip implants a finite element model optimized by virtual compatibility". Doctoral diss., University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4892.

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Bone mechanics and traditional implant materials produce a recurring problem for patients of total hip arthroplasty (THA): the bone is "shielded" from the loading it has become accustomed to over many years of development. Bone adheres to what is called "Wolff's Law", meaning it is an adaptive structure which adjusts its geometry based on the loads experienced over its life (Pearson; Goldstein). As the new femoral hip implant transmits reduced stresses to the remaining bone, bone tissue atrophies at the interface, permitting loosening of the implant, pain, and thereby obliging additional surgery to correct the issue (Meade). In the present work, a methodology is endeavored for creating an innovative design for femoral hip implants. The approach uncouples the finite element implant model from the bone model, in order to focus solely on expected behavior within the implant while considering the varying material behavior in unique directions and locations. The implant's internal geometry is optimized in order to better match typical, intact bone conditions. The eventual design reduces extreme changes in stresses within remnant bone such that the implant will remain implanted for greater periods of time without additional surgical attention.
ID: 030423147; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (Ph.D.)--University of Central Florida, 2011.; Includes bibliographical references (p. 86-91).
Ph.D.
Doctorate
Mechanical, Materials, and Aerospace Engineering
Engineering and Computer Science

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28

Chen, Qing-Li. "Effect of surface topography on hip prosthesis anchorage". Thesis, Queensland University of Technology, 1997.

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29

Watters, Eamon Patrick John. "Wear properties of artificial hip joint materials". Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321968.

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30

IWATA, HISASHI, SEIKI IWASADA, KOUICHI KAWAMOTO, TOSHIKI IWASE i YUKIHARU HASEGAWA. "MACROMOTION OF THE FEMORAL COMPONENT IN ARTIFICIAL HIP JOINT". Nagoya University School of Medicine, 1996. http://hdl.handle.net/2237/16103.

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31

Burgess, Ian C. "Tribological and mechanical properties of compliant bearings for total joint replacements". Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4720/.

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The tribology of a wide range of designs of compliant layer acetabular cups has been evaluated using a simulator. The simulator applied a dynamic load of 2 kN and a sinusoidal motion of ±25 , and measured the frictional resistance directly. In general the friction developed in these joints was extremely low, with friction factors typically below 0.01. When the experimental results were compared with theoretical estimates of friction a poor correlation was found. Further analysis suggested that the design of compliant layer acetabular cups was insensitive to many of the parameters suggested by theory. In particular, the radial clearance and femoral head size were not found to be critical. In addition, methods were proposed and their effectiveness demonstrated to measure friction at the on-set of motion (start-up friction), and the steady state friction in realistic compliant layer knees. The adhesion between compliant layers and a rigid backing have been investigated, with the aim of developing a good bond between them. The peel test was used to demonstrate an excellent diffusion bond between a low modulus medical grade polyurethane, and a similar high modulus grade of polyurethane. The processing conditions used to manufacture the test piece were optimised to maximise the bond strength. The bond was found to be stable after immersion in Ringers solution at 37 C for 52 weeks, and after acetabular cups were subjected to 14 million 4 kN loading cycles. A six station knee wear simulator was designed and commissioned. The simulator applied a dynamic load and an anterior-posterior translation individually to each station, as well as a flexion-extension motion common to all six stations. The simulator was computer controlled entirely using servo hydraulics. Wear rates were obtained from tests lasting up to 8 million cycles conducted on UHMWPE joints.

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32

Alfaro, Adrian Jesus. "Early migration and loosening of cemented femoral total hip replacement : an RSA study". Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301790.

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33

Liu, Yujing. "Finite element analysis of stress distribution within metal-on-metal joint replacements". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2012. https://ro.ecu.edu.au/theses/471.

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Demand for joint replacements is rising in Australia, driven by a sharp increase in the number of joint problems associated with population aging and obesity. In artificial joints, delamination or failure within the coatings occurs when the stress reaches a critical level, resulting in large wear debris particles appearing on the contact surface between the head and the cup. The process has been described as due to a stress-corrosion-cracking mechanism. Under the same loading, stress increases when the contact area decreases, which happens in the vicinity of wear debris. As such, once wear debris is generated, a catastrophic process could be initiated, resulting in more stress-corrosion-cracking. As such, acquiring a strong coating that will not fail is highly desirable for the applications of hip joint replacement. Failure in a coating layer is normally initiated by excessive local tensile or shear stress; therefore, it is important to clarify the stress distribution within the coating layer under different loading conditions, which is necessary for improving the load-carrying capability of the coating. Unlike previous studies, the multilayer diamond-like carbon (DLC) coatings having high elastic modulus and hardness were analysed in this work. Under normal contact conditions, plastic deformation occurs in contacting materials when the contact pressure is greater than the hardness of the materials. Therefore, high hardness coatings can resist plastic deformation to avoid failure of the coating; in addition, multilayer coatings can decrease stress concentration to avoid cracking. The purpose of this study is to determine whether DLC multilayer coatings can improve the property of the coating against potential cracking in the coating. It has been shown that structurally graded coatings had effect on reducing the contact-induced stress among all the factors considered. It is anticipated that the multilayer design parameters will be important to understand the stress distribution within metal-on-metal (MOM) hip replacements.

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34

Bartošík, Jan. "Vliv velikosti hlavice na procesy tření a mazání v TEP kyčle". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231946.

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This diploma thesis concerns itself with the experimental study of friction and lubrication in the artificial hip joint depending on the head size. Measurements were made in a hip joint simulator based on the principle of pendulum. For the friction measurements artificial joints, made from three material combinations and two diameters, from two companies were used. The measurements show that the material combination has a more significant effect to friction coefficient than the head size. Using a bigger head size shows a decrease in friction coefficient for all material combinations when compared to a smaller head size. For the measurement of lubrication film the colorimetric interferometry was applied. A metal-on-glass contact pair was used, where the glass cups were made according to the real measurements of the joint cups. Four types of hip replacements with diameters of 28 and 36 mm with two different diametral clearance were measured during a constant motion of 210 seconds. Measurements show, that the lubrication film in the hip joint with a small diametral clearance increases very fast over the 800 nm value. Contact surfaces in the hip joint with a large diametral clearance aren’t separated by the lubrication film, resulting in a damage of the chromium coating in cup. A thick lubrication film results in a higher friction coefficient, when compared with hip joints with a very thin or no lubrication film.

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35

Švachová, Michaela. "Experimentální analýza utváření mazacího filmu v náhradách kyčelního kloubu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241180.

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This diploma thesis deals with an experimental analysis of lubricant film formation in hip joint replacements. The main objective is to clarify the effect of mean speed, slide-to-roll ratio, and material of femoral head on the development of film thickness, focusing on the role of particular constituents contained in model synovial fluid, such as albumin and -globulin. For this purpose, a model ball-on-disc configuration was applied, while the development of lubricant film was evaluated using the combination of fluorescent microscopy and optical interferometry. To better understand the process, coefficient of friction between implant surfaces was later investigated as well. The effect of material, slide-to-roll ratio, mean speed and model fluid composition was analysed. Results indicate that the main parameter, influencing the character of film formation, is slide-to-roll ratio. Under most conditions, the dominant constituent responsible for the film thickness development was albumin. Coefficient of friction is affected mainly by the material of implant. The thesis contains original scientific results extending the knowledge in the area of hip joint biotribology.

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36

Balounová, Hana. "Studium tření náhrad kyčelního kloubu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230585.

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Diploma thesis deals with analysis of coefficient of friction in total hip prosthesis for several materials bearing with presence of bovine serum as substitute of synovial fluid occurred in natural joint. Behavior of coefficient of friction is observed on Mini Traction Machine. Results are plotted at graphs representing dependence of coefficient of friction on time. There are described effects of several kinematic conditions, the influence of used material and the effect of the method of contact lubrication. The experiments analyze how the formation of lubricant film with a layer of adsorbed protein affects coefficient of friction.

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37

Bosák, Dalibor. "Mapování tloušťky mazacího filmu u náhrad velkých kloubů člověka". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230068.

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This master’s thesis describes mechanism of lubricating film forming and its thickness in contact of a metal hip joint ball and a glass disc with chromium layer with presence of bovine serum as substitute of synovial fluid occured in a natural joint. Lubricating film thickness is evaluated by a thin film colorimetric interferometry, results are ploted at graphs representing dependence of lubricating film thickness on experiment duration or on mutual speed of articulating surfaces. There is described the influence of concentration of bovine serum and different kinematic conditions on lubricating film forming. From observed interferograms is apparent the adsorption of proteins to glass disc and femoral head surfaces, denaturation and formation of protein aggregations affecting the residual lubricating film thickness.

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38

Žonda, Peter. "Konstrukce simulátoru kyčelního kloubu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241896.

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The master's thesis is concerned with design and execution of an experimental acetabulofemoral joint simulator. Its primary use is the study of lubrication film thickness in hip implants. The work first describes available hip joint simulators, which simulate particular joint positions. Next, the thesis proposes author’s own designs and solutions. The result is a produced device allowing for dynamic change of load in simulation of hip joint flexion and extension as set by ISO standard. Contact is recorded by an optical apparatus composed of a high-speed camera and a microscope. The work also includes the initial testing experiment and the complete design documentation of the device including electrical wiring diagrams.

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39

Madsen, Michael S. "The effect of total hip arthroplasty surgical approach on gait kinematics". 2002. http://www.oregonpdf.org.

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40

Wang, Allan W. (Allan Wen Li). "Femoral bone remodelling following cemented hip arthroplasty in a sheep model / Allan W. Wang". 1998. http://hdl.handle.net/2440/19343.

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Bibliography: leaves 198-219.
xii, 219 leaves : ill. (chiefly col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Examines the effect of implant design on the femoral bone remodelling response in a sheep cemented hip arthroplasty model. The clinical section of the thesis also indicates the importance of biological factors in the femoral bone remodelling response.
Thesis (Ph.D.)--University of Adelaide, Dept. of Orthopaedics and Trauma, 1998

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41

Wang, Allan W. (Allan Wen Li). "Femoral bone remodelling following cemented hip arthroplasty in a sheep model / Allan W. Wang". Thesis, 1998. http://hdl.handle.net/2440/19343.

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Bibliography: leaves 198-219.
xii, 219 leaves : ill. (chiefly col.) ; 30 cm.
Examines the effect of implant design on the femoral bone remodelling response in a sheep cemented hip arthroplasty model. The clinical section of the thesis also indicates the importance of biological factors in the femoral bone remodelling response.
Thesis (Ph.D.)--University of Adelaide, Dept. of Orthopaedics and Trauma, 1998

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42

Brumby, Scott Andrew. "The effect of surface roughness and a collar on fixation of cemented femoral stems in vivo / by Scott Andrew Brumby". Thesis, 1996. http://hdl.handle.net/2440/18921.

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Bibliography: leaves 193-206.
xiii, 206 leaves : ill. (chiefly col.) ; 30 cm.
This thesis investigates the effect of femoral stem surface roughness and a collar on the fixation of cemented hip hemi-arthroplasty femoral stems in an in vivo sheep model up to nine months following implantation. Plain radiography, micromotion between prosthesis and bone during mechanical testing and histology are used.
Thesis (Ph.D.)--University of Adelaide, Dept. of Orthopaedics and Trauma, 1997?

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43

Baloyi, Nkele Martha. "Titanium-Zirconium-Niobium intermetallic composite coatings for orthopaedic applications". 2014. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001501.

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M. Tech. Metallurgical Engineering
Ti6Al4V alloy is the leading material for hip replacement because of its biocompatibility, elastic modulus and good yield strength, but shows poor corrosion and wear properties in simulated body fluid. Thin coatings were fabricated on Ti6Al4V alloy using Zirconium, Niobium and Titanium reinforcements with the aid of Nd:YAG Rofin Sinar laser system. Niobium reinforcement produced the best coating that displayed the best corrosion resistance and percentage increase in wear resistance in simulated body fluid as compared to the substrate. Therefore, this coating will perform best as orthopaedic implant material.

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44

Wei, Tzu-Hsaun, i 魏子瑄. "Contact Mechanics and Vibration Analysis of Artificial Hip Joint". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/89349108713838558796.

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碩士
國立高雄應用科技大學
機械與精密工程研究所
103
Total hip arthroplasty is one of the most successful and highest capable rate surgery in Taiwan in the past ten years. By total hip arthroplasty, patients replace the painful and functionless hip with hip endoprosthesis system and return to everyday activities. The influence of modal’s parameters on contact force and penetration depth in most of literatures which concern contact-impact modal of hip arthroplasty only show the tendency of the parameters. For the concrete value of the parameters, we use the analysis of variance to get the influence degree of the parameters of the contact-impact modal. The influence degree are Young’s modulus & Poisson’s ratio 46.22%, initial relative contact velocity 40.30%, joint clearance 8.64%, and shell size 1.83%. Then, we combined Taguchi method and fuzzy theory to find the best combination of these parameters. It is shell size 14mm, joint clearance 30μm, ceramic material, restitution coefficient 0.9, and initial relative contact velocity 0.6m/s. Finally, we use gait instances data on harmonic response analysis to make sure that our best combination modal won’t loosen.

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45

Ramjee, Shatish. "Numerical analysis of lubrication in an artificial hip joint". Diss., 2008. http://hdl.handle.net/2263/27954.

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The ageing population has become more active and live longer, these patients require hip replacement surgery at a younger age. Artificial hip implants, consisting of the acetabular cup and femoral head, affect the lives of many people, and the longevity of these implants pose significant concerns (rarely longer than 17 years). To help understand the lubricating performance of such a system, a hip joint model was built based on the Reynolds equation; the model developed simulated hydrodynamic lubrication. A steady-state angular rotation model was built whereby it was concluded that such motion would not support any load due to the anti-symmetric nature of the resultant pressure distribution (anti-symmetric about the axis of rotation). The pressure distribution from the steady-state rotation simulation contained a pressure source and sink which converged to the centre of the cup and whose pressure value increased in magnitude, as the eccentricity ratio increased. Infeasible results were obtained when the intermediary pressure constraint, allowing only positive pressure values, was implemented. The results obtained were not representative of the problem and it is recommended that this constraint not be implemented. The transient walking cycle model showed that a fluid with viscosity of 0.0015Pa.s is not sufficient to support a load in the walking cycle under conditions representative of hydrodynamic lubrication. Increasing the fluid viscosity promoted better results in the hydrodynamic model. Increasing the femoral head radius and decreasing the radial clearance between the components also improves the possibility of hydrodynamic lubrication. It is recommended that the model should be extended to investigate elasto-hydrodynamic lubrication. If possible, the effects of a boundary lubrication model should be investigated, as it is believed to be a major contribution to the lubrication of hip joints.
Dissertation (MEng)--University of Pretoria, 2008.
Chemical Engineering
unrestricted

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46

Wei, Chih-Chang, i 魏志漳. "INVESTING THE INTERFACE OF THE ARTIFICAL HIP JOINT". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/09600023593028106010.

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碩士
元智大學
管理碩士在職專班
104
The market of artificial joint continues to expand as the increasing global aging, rapid economic growth in the emerging countries, and the trend of health reform policies to increase the medical care coverage. The quality of life is greatly influenced by the joint disease and lesion, and the function of joint need to be restored by the total joint replacement. The complexity and variety of biological condition makes the implantation of artificial joint a great challenge, such as eliminate the rejection, restore the movement of the joint, and the long duration of the prosthetic implant. This study is to investing the interface of the artificial hip joint. The Delphi method is used to predict the priority of the material combination of the artificial joint interface, performance of the artificial joint, technology progress of the artificial joint interface by anonymous surveillance in expertise in this field. Moreover, a further prediction by expert is made regarding the market share, duration, wear resistance, and the cost between the interface combination of metal-polymer and ceramic-ceramic in the next 20 years. The results of the study show that the ceramic-ceramic interface of artificial joint would be the mainstream in the global total hip replacement market. The duration of the prosthetic implant can last for more than over 30 years. The ceramic artificial hip joint would become the best option for the patient. The progress of material technology could effectively lower not only the cost of the ceramic artificial hip joint, and but also the cost for the patient.

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47

Kuo, Tsun-En, i 郭存恩. "The finite element study of contact behavior of the artificial hip joint". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/16799717978141555955.

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碩士
國立中興大學
機械工程學系所
96
In general, having used for some period, the gap between femoral head and the acetabular cup is increased and the gait analysis may loss its significance. This research mainly focuses on the application of the finite element analysis with Hertz contact theorem and discusses the destruction situation of artificial hip joint between stem and acetabular cup under the gravity loads. The stem with bone cement and cortical bone contact one another and contact elements are applied. It includes the derivation of gravity loads due to separation of stem and acetabular cup and comparison of mechanical behaviors in the stem, the bone cement and the cortical shell with and without contact elements. The results show that, the larger the separation between stem and acetabular cup is, the greater the impact load is and the nonlinear relation between them is present obviously. The larger the femoral head and acetabular cup are, the smaller the impact loads are. The stresses generated on the contact surface of the stem are much different from those calculated from the general finite element results and more physically significant.

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48

Lei, Jeen-Bon, i 雷震邦. "Analysis the Biocompatibilities and Mechanical Properites of TPU/HA Composited Artificial Hip Joint". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/16232388285360975258.

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碩士
中山醫學大學
醫學研究所
102
The implantation of Artificial Hip Joints (AHJ) that made by metallic material is the main stream of orthopedic surgery. Due to metallic implant devices have large elastic modulus, therefore, they produce Stress Shielding Effect and results in most of the metallic implants loosen in femur shaft. Not only aseptic loosening may be occurred after long-term usage of the metallic implants, but also metallic implants release metal particles and ions to human body that may induce inflammation. To avoid such adverse responses, AHJ made by selected non-metallic material would be a better solution. In this study, we use thermoplastic polyurethane (TPU) and hydroxyapatite (HA) composited material to make the AHJ . We have designed seven experiments to investigate the biocompatibility and mechanical properties of this novel AHJ composite material . We found that the composite material maybe developed as whole non-metallic artificial hip joint and be benefit to those elder patients and prevent them suffer prosthesis revision again.

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49

Bai, Yu-Wei, i 白譽瑋. "Investigation on the effect of the Cement/Stem interface characteristics on the mechanical behavior of artificial hip joint". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/57146286530705071839.

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碩士
國立勤益科技大學
機械工程系
99
The integrity of the cemented fixation interface is responsible for the long-term longevity of prostheses used for artificial hip replacement. Metallic stems with roughened surfaces are considered to provide stronger adhesion with cement. However, clinical studies have reported that roughened stems show a lower survival rate than polished stems. Therefore, this study was conducted to investigate the mechanical effect of stem surface finish in cemented hip replacement. To accomplish this, a series of cement/metal specimens were tested under different loading configurations to assess the mechanical characteristics of the interface between cement and metal specimens with different surface finishes. A finite elemental model of cemented femoral prostheses was then created, in which the cement/stem interface was assumed to be in different bonding states according to the experimentally measured interface properties. The failure probabilities of the cement mantle and cemented interface generated under physiological loadings were evaluated. The experimental results indicated that the polished metal produced higher interfacial tensile and lower shearing strengths than the roughened metal. In addition, the polished stems were predicted to have a lower probability of cement mantle failure and higher integrity of the cement/stem interface when compared to the roughened stem. Overall, the results of this study provide significant evidence to support the clinical outcomes of cemented hip prostheses with different stem surface finishes.

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