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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.
161

Avaliação da articulação coxofemoral ipsilateral em indivíduos do sexo masculino com ruptura do ligamento cruzado anterior com e sem contato físico

Lopes Junior, Osmar Valadão January 2012 (has links)
Objetivo: Avaliar a amplitude de movimento (ADM) do quadril em pacientes que sofreram lesão do ligamento cruzado anterior (LCA), por traumatismo direto, e compará-la a de pacientes com a lesão por entorse sem contato físico sobre o joelho. Fazer uma análise radiográfica do quadril dos indivíduos avaliados. Método: A ADM do quadril foi avaliada em 35 pacientes com lesão do LCA ocorrida por traumatismo direto (grupo com contato) e comparada a de 45 pacientes que sofreram a lesão por entorse do joelho sem contato físico (grupo sem contato). A amplitude rotacional do quadril também foi avaliada segundo os pontos de corte de 70° e 80°. Exames radiográficos do quadril foram realizados para avaliar a presença de deformidade tipo cam e tipo pincer. Resultados: A ADM do quadril foi estatisticamente superior nos pacientes do grupo com contato. Os pacientes do grupo sem contato tiveram uma amplitude rotacional do quadril de 66,1° ± 8,4° comparada a 79,4° ± 10,6° do grupo com contato (p<0,001). Dos pacientes do grupo sem contato, 77,8% e 93,3% tiveram uma amplitude de rotação do quadril menor do que 70° e 80°, respectivamente, comparada a 17,1% e 42,9% do grupo com contato (p<0,001). Não houve diferença na prevalência de deformidade tipo cam ou pincer entre os grupos. A prevalência de cam e pincer não foi maior nos pacientes com limitação da amplitude de movimento. Conclusão: Na amostra avaliada, os pacientes com lesão do LCA ocorrida por entorse do joelho sem contato físico tiveram menor amplitude de movimento do quadril do que pacientes vítimas da lesão do LCA por traumatismo direto. A presença de deformidade tipo cam ou pincer foi semelhente em ambos os grupos e não esteve relacionada a uma diminuição da amplitude de movimento do quadril. / Objective: To evaluate the range of motion (ROM) of the hip in patients who suffered contact anterior cruciate ligament (ACL) injury and compare it to patients with non-contact ACL injury. To performe a hip radiographic analysis of all subjects included. Method: ROM of the hip was evaluated in 35 patients with contact ACL injury (contact group) and compared to that of 45 patients who suffered a non-contact ACL injury (non-contact group). The sum of hip rotation (IR+ER) was also assessed according to the cutoff points of 70° and 80°. Radiographic hip were performed to assess the presence of deformity cam and pincer type. Results: ROM of the hip was statistically higher in the patients with contact ACL injury. The average sum of hip rotation was 66.1° ± 8.4° in non-contact group compared to 79.4° ± 10.6° in contact group (p<0.001). Seventy-seven percent of patients in non-contact group had a sum of hip rotation less than 70° and 93% had less than 80°, repectivally, compared to 17.1% and 42.9% in the contact group (p<0.001). The prevalence of cam or pincer deformity was similar between groups. Cam or pincer deformity was not more frequent in patients with limited range of motion of the hip. Conclusion: In our study, patients with contact ACL injury had greater range of motion of the hip than patients that suffered non-contact ACL injury. The presence of deformity cam or pincer was similar in both groups and was not related to a decreased range of motion of the hip.
162

Avaliação radiográfica comparativa de quadris dolorosos e sem dor em indivíduos adultos / Comparative radiograph evaluation of adult patients with and with out hip pain

Omar Ferreira Miguel 15 September 2010 (has links)
O objetivo do estudo foi correlacionar a presença de alterações radiográficas em quadris de pacientes portadores de dor no quadril a um grupo de pacientes sem dor no quadril. Foram avaliados 122 pacientes com dor no quadril, e 100 pacientes sem dor no quadril. Todos com idade entre 20 e 50 anos. Os pacientes foram submetidos a exames radiográficos, nas incidências AP de pelve ortostático, falso perfil de Lequesne, Dunn, Dunn 45° e Ducroquet. Os parâmetros avaliados foram inclinação e versão acetabular, ângulo CE de Wiberg, espaço articular superolateral, ângulo , ângulo de Lequesne, ângulo VCA, diferença entre o raio da cabeça e do colo femorais (off set), esfericidade da cabeça femoral e a presença de ressalto na transição da cabeça com o colo femoral. Concluiu-se que as melhores incidências para o diagnóstico de impacto femoroacetabular são AP de pelve ortostático, Dunn 45° e Ducroquet, e que as seguintes alterações estão correlacionadas com dor nos quadris: off set diminuído, ângulo aumentado, ângulo de Lequesne aumentado, ângulo CE de Wiberg diminuído, espaço articular diminuído e presença de ressalto na transição cabeça-colo femoral / This study aimed to compare two groups of patients, with and with out hip pain, and correlate them with the existence of radiograph alterations. Weve studied 122 patients with hip pain and 100 asymptomatic; the ages were between 20 to 50 years old in both groups. All patients were roentnographicaly studied in anteroposterior pelvis in orthostatic position, Lequesne false profile, Dunns, Dunns 45° and Ducroquets view. The radiograph parameters analized were the acetabular inclination and vertion, Wiberg CE angle, Lequesne VCA angle, Lequesnes antevertion angle (), angle, superior and lateral joint space, femoral off set, nonspherical of the femoral head and the presence of a bump on the head-neck transition. We conclude that the best incidences to diagnosis of femoroacetabular impingement are AP pelvis orthostatic, Dunn 45° and Ducroquet. The following alterations are correlate with hip pain: lower off set, higher angle, higher Lequesne angle, lower CE angle of Wiberg, lower articular space and bump in the femoral head-neck transition
163

Avaliação da articulação coxofemoral ipsilateral em indivíduos do sexo masculino com ruptura do ligamento cruzado anterior com e sem contato físico

Lopes Junior, Osmar Valadão January 2012 (has links)
Objetivo: Avaliar a amplitude de movimento (ADM) do quadril em pacientes que sofreram lesão do ligamento cruzado anterior (LCA), por traumatismo direto, e compará-la a de pacientes com a lesão por entorse sem contato físico sobre o joelho. Fazer uma análise radiográfica do quadril dos indivíduos avaliados. Método: A ADM do quadril foi avaliada em 35 pacientes com lesão do LCA ocorrida por traumatismo direto (grupo com contato) e comparada a de 45 pacientes que sofreram a lesão por entorse do joelho sem contato físico (grupo sem contato). A amplitude rotacional do quadril também foi avaliada segundo os pontos de corte de 70° e 80°. Exames radiográficos do quadril foram realizados para avaliar a presença de deformidade tipo cam e tipo pincer. Resultados: A ADM do quadril foi estatisticamente superior nos pacientes do grupo com contato. Os pacientes do grupo sem contato tiveram uma amplitude rotacional do quadril de 66,1° ± 8,4° comparada a 79,4° ± 10,6° do grupo com contato (p<0,001). Dos pacientes do grupo sem contato, 77,8% e 93,3% tiveram uma amplitude de rotação do quadril menor do que 70° e 80°, respectivamente, comparada a 17,1% e 42,9% do grupo com contato (p<0,001). Não houve diferença na prevalência de deformidade tipo cam ou pincer entre os grupos. A prevalência de cam e pincer não foi maior nos pacientes com limitação da amplitude de movimento. Conclusão: Na amostra avaliada, os pacientes com lesão do LCA ocorrida por entorse do joelho sem contato físico tiveram menor amplitude de movimento do quadril do que pacientes vítimas da lesão do LCA por traumatismo direto. A presença de deformidade tipo cam ou pincer foi semelhente em ambos os grupos e não esteve relacionada a uma diminuição da amplitude de movimento do quadril. / Objective: To evaluate the range of motion (ROM) of the hip in patients who suffered contact anterior cruciate ligament (ACL) injury and compare it to patients with non-contact ACL injury. To performe a hip radiographic analysis of all subjects included. Method: ROM of the hip was evaluated in 35 patients with contact ACL injury (contact group) and compared to that of 45 patients who suffered a non-contact ACL injury (non-contact group). The sum of hip rotation (IR+ER) was also assessed according to the cutoff points of 70° and 80°. Radiographic hip were performed to assess the presence of deformity cam and pincer type. Results: ROM of the hip was statistically higher in the patients with contact ACL injury. The average sum of hip rotation was 66.1° ± 8.4° in non-contact group compared to 79.4° ± 10.6° in contact group (p<0.001). Seventy-seven percent of patients in non-contact group had a sum of hip rotation less than 70° and 93% had less than 80°, repectivally, compared to 17.1% and 42.9% in the contact group (p<0.001). The prevalence of cam or pincer deformity was similar between groups. Cam or pincer deformity was not more frequent in patients with limited range of motion of the hip. Conclusion: In our study, patients with contact ACL injury had greater range of motion of the hip than patients that suffered non-contact ACL injury. The presence of deformity cam or pincer was similar in both groups and was not related to a decreased range of motion of the hip.
164

Napjatostní analýza keramické hlavice totální kyčelní endoprotézy zatížené dle ISO 7206-5 / Stress analysis of the total hip joint endoprosthesis head under ISO 7206-5 loading

Varga, Jozef January 2008 (has links)
The aim of this work is to analyse axisymetric tasks by norm ISO 7206-5, which is used to determination of static strength of ceramic heads. In the numeric analysis there will be considered form variances from nominal conicalness and circularity of stem sections i.e. possible variances caused by production. Furthermore form changes of recess inside of the head measured on real samples will be considered. All these variances from nominal values are necessary to analyse in more details, because they can participate in destruction of ceramic heads. The stem system, ceramic head and load cone (DHK) will be simulated as a 2D axisymetric task and 3D quarter symetrical task. That is why is necessary to undertake also comparing analysis of 2D and 3D tasks and compare results or eventually evaluate the error. This problem is solved using of Finite element System ANSYS 11.0.
165

Deformačně napěťová analýza BS dlahy / Strain stress analysis of BS splint

Řehák, Kamil January 2010 (has links)
This master‘s thesis deals with strain-stress analysis of hip joint together with the final applied total endoprosthesis with Burch-Schneider cage. The main point of my work was to find the solution of stress–strain analysis state, which has been mentioned before in connection with Burch-Schneider cage. I describe the technique of geometric creation of whole body system, component´s materials or conditions which are neccessary for calculation. In coclusion there are results achieved in variants. In the first option the case of bone tissue was considered, which don’t reach degradation mechanical properties effect straining under Burch-Schneider cage. In some cases when the bone tissue is untimely forced, the necrosis of bone tissue takes place under Burch-Schneider cage. This possibility is described in the second option of type. For every option there was a case which was calculated with applied screw or without it. In all option mechanical features of cancellous bone tissue and their change influence on achieved results were considered. This problem was solved computational simulation in commercial software Ansys Workbench 12.0.
166

Mapování tloušťky mazacího filmu u náhrad velkých kloubů člověka / Mapping of lubricating film thickness of human big joints replacements

Bosák, Dalibor January 2012 (has links)
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.
167

Konstrukce simulátoru kyčelního kloubu / Design of hip joint simulator

Žonda, Peter January 2016 (has links)
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.
168

Größere Köpfe kompensieren erhöhte HTEP-Luxationsgefahr bei Hochrisikopatienten: Eine Fallserie mit Literaturüberblick: Größere Köpfe kompensieren erhöhte HTEP-Luxationsgefahr beiHochrisikopatienten: Eine Fallserie mit Literaturüberblick

Philipp, Henry Peter 06 September 2016 (has links)
Die Zielsetzung dieser Arbeit besteht darin zu prüfen, ob die Luxationsrate bei Hochrisikopatienten durch den Einsatz von 40-mm- und 44-mm-Köpfen im Vergleich zu Patienten mit maximal 36-mm-Köpfen reduziert werden kann. Hierzu wurden die im Zeitraum von September 2009 bis Mai 2014 hüftendoprothetisch versorgten Patienten mit einem erhöhten Luxationsrisiko erfasst und die Verläufe auf Luxationen überprüft. Zur Risikobewertung diente eine eigens entwickelte Klassifikation. Des Weiteren erfolgte die Analyse der postoperativen Verläufe, der Röntgenbilder und eines Telefoninterviews in den Fällen, in denen Köpfe ≥ 40 mm zum Einsatz kamen. Im Untersuchungszeitraum wurden 288 Hüftendoprotheseneingriffe mit erhöhtem Luxationsrisiko durchgeführt. Bei 278 HTEP-Implantationen erfolgte der Einsatz von Gelenkköpfen ≤ 36 mm. In dieser Gruppe betrug die Luxationsrate 15,1% (n=42). Bei 10 Patienten wurden 40-mm- oder 44-mm-Gelenkköpfe eingesetzt. In diesen Fällen wurde das Luxationsrisiko entsprechend der vorgeschlagenen Klassifikation mit 3A (hoch) bis 4B (sehr hoch) bewertet. Bei einem mittleren Follow up von 22,8 Monaten wurde bei diesen Patienten keine Luxation festgestellt. Die mit 40-mm- sowie 44-mm-Köpfen erzielten Ergebnisse und die aktuelle Literatur sprechen für eine wesentlich höhere Gelenkstabilität und eine deutlich verminderte Luxationsneigung größerer Köpfe. Deren Einsatz ist daher gegenwärtig bei Risiko-patienten gerechtfertigt, sofern dieser in Abhängigkeit vom Pfannenaußendurch-messer konstruktiv möglich ist. In der weiteren Entwicklung der Hüftendoprothetik sollte die Verwendung größerer Köpfe angestrebt werden.:Inhaltsverzeichnis Bibliographische Beschreibung Abkürzungsverzeichnis 1. Einleitung 1.1 Bedeutung der Hüftendoprothetik 1.2 Hüftendoprothesenluxation 1.2.1 Definition und Häufigkeit 1.2.2 Ursachen 1.2.3 Einteilung und Klassifikation 1.2.4 Risikofaktoren 1.2.5 Beurteilung des Luxationsrisikos bei hüftendoprothetischen Eingriffen 1.2.6 Ursachen des luxations-mindernden Effektes großer Köpfe 1.2.7 Vorgehen nach Luxation 1.2.7.1 Diagnostik 1.2.7.2 Therapie 1.3 Zielsetzung der Arbeit 2. Publikation 3. Zusammenfassung 4. Literaturverzeichnis 5. Tabellenverzeichnis 6. Abbildungsverzeichnis 7. Erklärung über die eigenständige Abfassung der Arbeit 8. Lebenslauf und wissenschaftlicher Werdegang 9. Danksagung 10. Anlagen Anlage 1 - Dokumentationsbogen Patienten mit Großköpfen Anlage 2 - Telefoninterviewbogen zu 40/44mm Köpfen
169

Har retroverterade höfter större grad av passiv flexion i ett mer abducerat och utåtroterat läge? / Does retroverted hips have greater passive hip flexion in combination with abduction and external rotation?

Bergqvist, Noah, Johansson, Elias January 2023 (has links)
Introduktion: Anatomiska variationer i det muskuloskeletala systemet är vanliga bland oss människor och behöver inte nödvändigtvis medföra ökad risk för besvär, men kan påverka en individs funktion. Inom fysioterapi är det viktigt med vetskapen om anatomiska variationers påverkan för att optimalt individanpassa behandling. En typ av anatomisk variation är vinkeln av lårbenshalsen gentemot frontalplanet. Det finns en stark evidens för hur lårbenshalsens vinkel påverkar höftens inåt- och utåtrotation, men det finns begränsad information om hur det påverkar rörligheten i andra rörelseriktningar.   Syfte: Att undersöka om höfter med ‘femoral neck retroversion’ (FNR) har en större grad av passiv flexion i kombination med utåtrotation och abduktion jämfört med enbart passiv flexion i sagittalplan.    Metod: För att avgöra om höfter mötte inklusionskriteriet att en retroversion fanns användes Craig ́s test. Interbedömarreliabilitet av Craig´s test undersöktes med ‘intraclass correlation coefficient’ (ICC). Passiv inåt/utåtrotation mättes sittande på brits och passiv flexion i sagittalplan utfördes ryggliggandes. Vid mätning av passiv flexion i kombination med utåtrotation och abduktion letades det potentiella läget där låret kunde nå närmast bröstet. Goniometer av typ Brodin med 31 cm skänklar användes vid samtliga mätningar. Wilcoxons icke-parametriska test användes för att analysera differensen mellan passiv flexion i kombination med utåtrotation och abduktion och passiv flexion i sagittalplan.  Resultat: 23 personer mellan 18 och 48 år rekryterades, varav 10 kvinnor och 13 män. Därmed undersöktes 46 ben. ICC vid Craig´s test blev 0.73, vilket klassas som moderat reliabilitet. En signifikant skillnad mellan passiv flexion i sagittalplan och passiv flexion i kombination med utåtrotation och abduktion sågs för inkluderade ben (p &lt;0.001). Medianen för denna skillnad var 19o.  Slutsats: Retroverterade höfter har en större grad av passiv flexion i ett mer abducerat och utåtroterat läge jämfört med enbart passiv flexion i sagittalplan. Vidare forskning bör undersöka om det finns ett samband mellan den exakta FNR-vinkeln och differensen mellan flexion i sagittalplan och flexion i kombination med utåtrotation och abduktion. Vidare kan även differensen i flexion jämföras mellan olika grupper med FNR, ‘femoral neck anteversion’ (FNA) och normalspann. Validitet och reliabilitet bör undersökas närmare för metoden att bestämma flexionsvinkel i ett mer abducerat och utåtroterat läge.
170

Friction and lubrication behaviour of hip resurfacing metal-on-metal and ZTA ceramic on CFR peek implants with various diameters and clearances. Friction and lubrication behaviour of hip resurfacing Co-Cr-Mo and zirconia toughened alumina ceramic heads against carbon fibre reinforced poly-ether-ether-ketone cups with various diameters and clearances have been investigated using serum-based lubricants.

Ehmaida, Mutyaa M. January 2012 (has links)
Total hip joint prostheses made of CoCrMo heads versus ultra high molecular weight polyethylene (UHMWPE) cups have a limited lifetime, mainly due to the wear of the UHMWPE cups as a result of high friction between the articulating surfaces leading to osteolysis and implant loosening with revision surgery becoming inevitable in more active patients. Tribology plays an important role in developing the design, minimizing wear and reducing friction of hip joint prostheses in order to improve their long-term performance, with good lubricating properties. Metal-on-metal hip resurfacing prostheses have shown significantly lower wear rates compared with conventional metal-on-polyethylene implants and thus osteolysis is potentially reduced leading to increased lifetime of the prosthesis. Nevertheless, excessive wear of metal-on-metal joints leads to metal ion release, causing pseudo-tumours and osteolysis. An alternative approach to such bearings is the use of newly developed carbon fiber-reinforced poly-ether-ether-ketone (CFR PEEK) acetabular cups articulating against ceramic femoral heads due to their better wear resistance compared to UHMWPE. In this study, therefore, friction and lubrication properties of large diameter, as cast, Co-Cr-Mo metal-on-metal hip resurfacing implants with various diameters and clearances have been investigated and compared to those of the newly developed zirconia toughened alumina (ZTA) ceramic femoral heads articulating against carbon fiber reinforced poly-ether-ether-ketone (CFR PEEK) acetabular cups with different diameters and clearances. Friction hip simulator was used to measure frictional torque and then friction factors were calculated along with Sommerfeld numbers leading to Stribeck analysis and hence the lubricating mode was also investigated. This involved using lubricants based on pure bovine serum (BS) and diluted bovine serum (25 vol. %BS+75 vol. %distilled water) with and without carboxymethyl cellulose (CMC) (as gelling agent). Standard Rheometer was used to measure lubricant viscosity ranged from 0.0014 to 0.236 Pas at a shear rate of 3000 . Pure bovine serum, diluted bovine serum without CMC and with CMC (25BS+75DW+0.5gCMC and +1gCMC) showed pseudoplastic flow behaviour up to shear rate of ¿139 above which a Newtonian flow with significant increase in shear stress was observed. The viscosity flow curves for the 25BS+75DW+2gCMC, +3.5gCMC and +5gCMC showed only shear thinning up to a shear rate of 3000 . The shear rate application modified the flow behaviour of bovine serum from a pseudoplastic to a Newtonian flow depending on its purity and CMC content. This will cause a different frictional behaviour depending on joint diameter and clearance, as seen in this work. The experimental data were compared with theoretical iv predictions of the lubricating regimes by calculating theoretical film thickness and lambda ratio. The metal-on-metal Biomet ReCaps showed similar trends of Stribeck curves, i.e. friction factors decreased from ~0.12 to ~0.05 as Sommerfeld numbers increased in the range of viscosities ~0.001-0.04Pas indicating mixed lubrication regimes above which the friction factor increased to ~0.13 at a viscosity of 0.236Pas. The Stribeck analyses suggested mixed lubrication as the dominant mode with the lowest friction factor in the range ~0.09 - ~0.05 at the physiological viscosities of ~0.01 to ~0.04 Pas and that such joints can be used for more active patients as compared to the conventional total hip replacement joints with 28mm diameter. The Stribeck curves for all ZTA ceramic-on-CFR PEEK components illustrated a similar trend with BS fluids showing higher friction factors (in the range 0.22-0.13) than the diluted BS+CMC fluids (in the range 0.24-0.05). The friction tests revealed boundary-mixed lubrication regimes for the ZTA ceramic-on-CFR-PEEK joints. The results, so far, are promising and suggest clearly that the newly developed ZTA ceramic femoral heads articulating against CFR PEEK cups have similar friction and lubrication behaviour at optimum clearances to those of currently used metal-onmetal hip resurfacing implants at the range of viscosities 0.00612 to 0.155Pas. These results clearly suggest that the ZTA ceramic-on-CFR-PEEK joints showed low friction at the physiological viscosities of ~0.01Pas in the range ~0.1-0.05, suggesting that these novel joints may be used as an alternative material choice for the reduction of osteolysis. The result of this investigation has suggested that the optimum clearance for the 52mm diameter MOM Biomet ReCaps could be ~170¿m. However, 48 and 54mm joints showed lower friction due to clearances to be >200¿m. For the 52mm ZTA ceramic-on-CFR-PEEK joints the optimum clearance seems to be ¿ 630¿m radial clearance. These results suggested that increased clearance bearings have the potential to generate low friction and hence no risk of micro- or even macro-motion for the ceramic-on-CFR-PEEK joints. This study found no correlation between theoretical predictions and experimental data for all metal-onmetal and ZTA ceramic-on-CFR PEEK bearings at the physiological viscosity (0.0127Pas). However, at lubricant viscosity of 0.00157Pas, the theoretical prediction of lubrication regime correlated well with the experimental data, both illustrating boundary lubrication. As expected, a decrease in viscosity resulted decrease in the film thickness.

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