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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

The effect of four different manipulative techniques on Iliotibial Band Friction Syndrome (ITBFS) in terms of primary and secondary outcome measures

Botes, Jacques Andre January 2016 (has links)
Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / Background: Iliotibial band friction syndrome is a common dysfunction seen in athletes. Athletes develop biomechanical changes yet still continue with their sport. However, this syndrome limits their ability to participate at peak performance. This study determined which participants benefitted in terms of biomechanical and clinical outcomes in one of four groups: ankle joint, superior tibio-fibular joint, sacroiliac joint or a combination manipulation group (which contained any two of the three joint restrictions). Methods: This Durban University of Technology Institutional Research and Ethics Committee approved prospective clinical trial, utilised stratified sampling, with 48 participants across four groups: ankle (14); superior tibio-fibular (11), sacroiliac (12) and combination (11). The participants underwent six treatments in three weeks. Data collection occurred before consultations one, three, five and seven. The data included primary measures of the knee score questionnaire (KSQ), the algometer, the visual analogue scale (VAS) and the secondary measures of the Feiss line, the heel leg alignment, bilateral leg length, Q angle and tibio-femoral angle. All data was computed utilising the ANOVA testing, with a p-value <0.05 being significant and a 95% confidence interval. Pearson’s correlations were completed for intragroup associations between primary and secondary outcome measures. Results: The intragroup analysis revealed that all groups had significant changes in the KSQ and VAS, with the exception of the sacroiliac joint manipulation group (KSQ outcome not significant). Intergroup analysis revealed no differences between the groups with the exception of the combination group, which showed a significant increase in the tibio-femoral angle. Most commonly, the Pearson’s correlation revealed that changes in leg length were related to differences in primary outcome measures, irrespective of the group being tested. Conclusion: The outcomes of this study indicated that manipulation of the distal kinematic chain improved alignment and clinical outcomes to a greater degree than manipulating proximal restrictions. It is suggested with caution (due to limited sample size) that patients should first have their distal kinematic chain manipulated before more proximal joints are manipulated to achieve better outcomes. / M
182

Deformačně napěťová studie Burch-Schneiderovy dlahy / Strain Stress Study of Burch-Schneider Split

Řehák, Kamil January 2018 (has links)
This thesis deals with problems of the hip endoprosthetics area, namely total endoprosthesis (TEP) with Burch-Schneider (BS) split, in which there are many problems in clinical practice. The hip joint load depends on the patient weight and the performed activity. Sedentary job, little exercise, a lot of stress or poor eating habits and overweight associated with it affect negatively hip joint. Increasing hip joint wear and its pain in movement is necessary in several cases to be solved by a surgical procedure in which TEP is applied. When selecting and subsequently applying individual TEP, it is important to pay attention to creating conditions which will allow good fixation. In case of worse mechanical properties of bone tissue, it is very problematic to ensure stability of the implant. Based on several classifications which assess the degree of hip joint damage, it is possible to select a suitable TEP. The BS split, on which this work is focused, is dominantly used in cases of large defects in the acetabulum area. The use of this cage allows to bridgelarge defects and create a new centre of rotation of the hip. Knowledge of the mechanical properties of hip bone tissue can significantly affect the prediction of BS split damage. For this purpose, it was necessary to perform a biomechanical study, which is focused on the influence of worse mechanical properties of bone tissue on BS split failure. The computational modelling using finite element method implemented in the ANSY S software was used for the solution, which enables to solve the mechanical interaction between bone tissue and TEP with BS split. Due to the absence of bone tissue data before application of TEP with BS split, the variants before application of TEP and after application of resurfacing and standard TEP were solved. All variants were solved with the material properties of bone tissue that were determined based on CT images. In addition, all variants were solved for the case of degraded mechanical properties. Based on the numerical simulations results and the Mechanostat hypothesis, a bone tissue analysis of the hip joint was performed before and after application of TEP and TEP with BS split. The results show the influence of the computational model level, which considers the distribution of bone tissue through the inhomogeneous model of the material. Therefore, the degraded mechanical properties have a major impact on the stability and strain of the BS split, particularly in the cranial part of the acetabulum.
183

Návrh a vývoj experimentálního zařízení pro testování kloubní jamky TEP kyčelního kloubu a identifikace otěru pomocí optické metody / Design and Development of Experimental Device for Testing the TEP Acetabula and Wear Identification using Optical Method

Houfek, Martin January 2011 (has links)
Today is the implantation of joint replacements, although a radical, but very functional restoration frequent way ill joint. The implants are placed high demands on their biocompatible and long-term function, which is directly related to wear of joint replacements in the human body. Therefore, analysis of the complex behavior of the implant in the human body is a fundamental problem of biomechanics of implants. This issue is dedicated, this dissertation thesis. Dissertation thesis deals with the solution design and development of experimental device for testing the TEP acetabula and wear identification using optical method. The proposed device allows the joint burden hole TEP physiological manner, but by working with the acetabulum burdened by Power resultant joint axis passes through the hole. The physiological loading of articular wells and evaluating the size of the loss of polyethylene is currently intensively addressed. The results of this study may in the near future, serving as information for assessing the conduct of wear prosthetic hip joint in vivo. The work is devoted to solving the problem of the size required to detect the loss of polyethylene for joint replacement arthroplasty: Design and development of experimental equipment for testing the acetabulum of the hip joint arthroplasty. Identify wear using optical methods. Design and development of experimental equipment was made in the system Inventor Professional 2010 at the level of 3D modeling. Great attention was paid to the design fit into the acetabulum TEP testing machines and gripping the acetabulum into an optical device. Management options were tested with combinations of experimental equipment engines. Suggestions were made and then tests for fixing the acetabulum into an optical device. Has the possibility of depth analysis and identification of wear joined with innovative solutions to evaluate the loss of polyethylene acetabulum arthroplasty. Identification of abrasion (loss of polyethylene) joint arthroplasty holes were carried out experimental measurements using an optical holographic interferometry. The comprehensive analysis of the results of experimental measurement of the loss of polyethylene shows that this method can identify both the size but also an area where there is even to small changes in the surface, which depend on the abrasion. One can also say that using this method we are able to affect the will or displacements that affect the size of the loss of polyethylene in joint arthroplasty hole. Despite the number of known and lessons learned arising from the results of solving the problem of design and development of experimental equipment for testing the acetabulum and hip arthroplasty wear identification using optical methods, this work is that the initial study to identify problematics wear of joint replacements. Complete resolution of this issue is beyond the scope of one doctoral thesis.
184

Pravděpodobnosti porušení keramické součásti s využitím Weibullovy teorie nejslabšího článku / Failure probability of the ceramics part using Weibull weakest link theory

Kovář, Jaroslav January 2018 (has links)
This thesis compares Weibull weakest link theory with inclusion of one and all three principal stresses. Principal stresses needed for this theory were calculated with finite element method. The informational research is in the introduction of this thesis. It includes ceramic materials, Weibull weakest link theory, Gaussian quadrature over spherical surface and ceramic head of hip joint endoprothesis. Theoretical part is used for next calculations of probability of failure. The probability of failure of ceramic rod loaded by four-point bending is calculated in first calculations. This task is solved as contact in the next step. Next part of this thesis is about selection of suitable method of numerical integration. This method will be used in the calculation with all three principal stresses. The results of calculation with all three principal stresses are compared with the results of the calculation which includes only first principal stress. Firstly, this is done for cylindrical body and then used on head of hip joint endoprothesis. In the last part of this thesis, probability of fracture of head hip joint endoprothesis with shape deviation of nominal conicity is calculated.
185

A Paleopathological Assessment Of Osteoarthritis In The Lower Appendicular Joints Of Individuals From The Kellis 2 Cemetery In The Dakhleh Oasis, Egypt

Robin, Joshua B 01 January 2011 (has links)
Osteoarthritis (OA) is a degenerative pathological condition of the appendicular joints which affects the cartilage and underlying bone. OA is relatively common in both the archaeological and clinical context, and a significant amount of research has been conducted on this osteological condition. The purpose of this thesis is to assess the incidence, demographic prevalence, and general severity of hip and knee OA in a Roman-Christian period (50 A.D – 450 A.D) population sample from the Dakhleh Oasis, Egypt. The bioarchaeological sample originates from the Kellis 2 cemetery which is associated with the ancient town of Kellis. The town of Kellis is believed to have been a prosperous economic hub in Egypt, located in the Western Sahara Desert approximately 250 kilometers west of the Nile. The skeletal samples (n=135, 83 females and 51 males) was visually assessed for the osteological characteristics of OA in the hips and the knees. Joint surfaces of the hip include the acetabulum and femoral head. Joint surfaces of the knee include lateral/medial tibio-femoral compartments and the patellofemoral compartment. The ages of the individuals assessed in this study range from 19-72 years, and have been divided into five age categories which were then cross-tabulated with sex and OA incidence in order to determine demographic prevalence of OA. Findings indicate that age is a significant etiological factor of OA prevalence for both males and females. Males are afflicted by the disease significantly more than females in the hips (F: [L] 3.6%, [R] 5.9% and M: [L] 13.7%,[R] 13.7%) and also slightly more affected in the knees(F: [L] 17.5%,[R] 18.3% and M: [L] 22.9%,[R]21.3%). The acetabulum tends to be more arthritic than the femoral head for both males and females. Femoral condyles tend to be more arthritic than tibial condyles for both males and females. The patello-femoral compartment tends iv to be the most arthritic part of the knee while the medial condyles of both tibiae exhibit virtually no OA (with the exception of one individual). The joint surface observed with the highest OA prevalence is the femoral surface of the patella (F: [L] 17.5%,[R] 15.9% and M: [L] 21.3%,[R] 21.3%). The highest prevalence of OA by joint complex is observed on the left knee in males (22.9%), and the lowest prevalence of OA is observed on the left hip of females (3.6%). Both hip and knee joints have higher prevalence of unilateral OA manifestation than bilateral. Isotopic and archaeological evidence indicates that the individuals at Kellis maintained an agricultural subsistence regime, and that the males within the population may have been highly mobile migrating to and from the Dakhleh Oasis. Subsistence agriculture has its necessary physical demands which may have been a contributory factor to OA rates. Males show higher OA rates than females throughout the joints of the legs. Sexual dimorphism of OA for the hips is suggestive of sexual divisions of labor. OA of the knees lacks sexual dimorphism therefore the knee joint complex of males and females were likely subjected to similar levels of mechanical loading. It can be concluded based on the OA data that males and females exhibit similar activity, or biomechanical stress levels in the knee joint complexes. Males exhibit significantly higher pathological manifestation of OA in the hip joint complexes, indicative of higher levels of mechanical loading in the hip joint complex which can theoretically be attributed to sexual divisions of labor or perhaps terrestrial mobility

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