Dissertations / Theses on the topic 'Joints – Surgery'
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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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Bosanquet, Arthur G. "The effect of meniscal surgery on sheep temporomandibular joints." Title page, contents and summary only, 1988. http://web4.library.adelaide.edu.au/theses/09DM/09dmb741.pdf.
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Includes bibliographical references. Temporomandibular joint (TMJ) pain and dysfunction occurs commonly in the general population. Various surgical procedures have been used in the management of those patients who have not responded to conservative measures. Research into the surgical management of TMJ dysfunction and pathology has been restricted due to the lack of a suitable animal model. This study was undertaken initially to develop the sheep as an animal for TMJ research. The study has shown that Australian Merino sheep, with a TMJ broadly similar in size to humans, provides a satisfactory experimental model for TMJ research.
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Arslanian, Christine Lucy. "Pain perception and joint mobility before and after total knee arthroplasty." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276616.
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Joint mobility is dependent on comfort, thus pain is associated with mobility. This study examined the relationship between pain perception and joint mobility in arthritis patients before and after total knee arthroplasty. Pain perception was indicated by pain intensity, pain distress and pain expectation; joint mobility was represented by the degree of knee joint flexion. Visual analogue scales were used for pain intensity, pain distress and pain expectation; knee joint flexion as measured using a goniometer. Data were collected on 24 subjects preoperatively (T1), immediately postoperatively (T2) and forty-eight to seventy-two hours postoperatively (T3). Twenty-four subjects participated in the study. Significant paired t-test resulted for joint flexion at T1 and T3 and pain expectation at T2 and T3. Pearson product-moment correlation coefficients were significant for pain intensity and pain distress at all three times, pain intensity and joint flexion at T1 and pain intensity at T1 and at T2.
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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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Lam, Kwok-wai, and 林國偉. "Design and development of a new prosthetic device for proximal interphalangeal joint replacement." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3889161X.
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Zou, Haiou, and 鄒海歐. "The health related quality of life (HRQOL) of Chinese patients following total joint replacement surgery." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B27776116.
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Fowler, Nicola K. "Biomechanics of the rheumatoid proximal interphalangeal joint." Thesis, University of Strathclyde, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364344.
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Joshi, Shailesh Vasant. "Intra-operative shape acquisition of tibio-femoral joints using 3D laser scanning for computer assisted orthopaedic surgery : a proof of concept." Thesis, University of Strathclyde, 2015. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24915.
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Image registration is an important aspect in all computer assisted surgeries including Neurosurgery, Cranio-maxillofacial surgery and Orthopaedics. It is a process of developing a spatial relationship between pre-operative data, such as Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI) scans and the physical patient in the operating theatre. Current image registration techniques for Computer Assisted Orthopaedic Surgery (CAOS) in minimally invasive Unicompartmental Knee Arthroplasty (UKA) surgery are invasive, time consuming and often take 14-20 minutes and are therefore costly. The rationale for this study was to develop a new operating theatre compliant, quick, cost effective, contactless, automated technique for image registration during CAOS based on an accurate rigid body model of the ends of the exposed knee joint, produced using 3D laser scans taken intra-operatively by a Laser Displacement Sensor. Bespoke automated 3D laser scanning techniques based on the DAVID Laserscanner method were developed and were used to scan surface geometry of the knee joints in cadaveric legs. The laser scanned knee joint models were registered with the pre-operative (MRI/CT) models and the deviations were evaluated. Furthermore, trends in the deviations were studied along with a supportive validity study. Results indicated that the laser scanner can repeatedly produce accurate 3D models of the human tibio-femoral joint in the operating theatre. This study has provided a proof of concept for a new in situ automated shape acquisition and registration technique for CAOS with the potential for providing a quantitative assessment of the articular cartilage integrity during lower limb arthroplasty.
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Marzok, Mohamed Abdel-Moniem Abdel-Maksoud [Verfasser]. "Minimal invasive phalangeal joints surgery with the aid of the C-arm fluoroscopy technique / submitted by Mohamed Abdel-Moniem Abdel-Maksoud Marzok." Berlin : Mensch-und-Buch-Verl, 2006. http://d-nb.info/979382785/34.
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van, Essen Ellen. "The efficacy of arcuate dynamic traction splintage in the treatment of intra-articular fractures of the proximal interphalangeal joints of the hand a retrospective descriptive review : this dissertation [thesis] is submitted to Auckland University of Technology in partial fulfillment for the degree of Master of Health Science, October 2003 /." Full thesis. Abstract, 2003. http://puka2.aut.ac.nz/ait/theses/VanEssenE.pdf.
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Köhnlein, Werner Volker. "Acetabular morphology : implications for joint preserving surgery /." [S.l.] : [s.n.], 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Mcguire, Duncan Thomas. "Pyrocarbon proximal interphalangeal joint arthroplasty." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/11636.
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Arthritis of the proximal interphalangeal joint of the hand can be debilitating disease resulting in pain and stiffness. Treatment is initially conservative but with diseasse progression surgical treatment often becomes necessary. Arthroplasty is one of the surgical options available.
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Saro, Carlos. "Hallux valgus surgery : epidemiological aspects and clinical outcome /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-233-0/.
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Reátegui, Villegas Diego Artemio. "Repercusión de la hiperglicemia en el postoperatorio de pacientes operados de artroplastia total de rodilla." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/403586.
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La Diabetes Mellitus (DM) es una enfermedad metabólica cuya prevalencia va en aumento debido a los cambios en los hábitos de vida en la sociedad actual. En España se estimó en el 2006, que la prevalencia de la DM tipo 2 variaba entre el 4,8% y el 18,7%. En EEUU la prevalencia de la DM es de 9,3%. A nivel mundial, la prevalencia de la DM se estimó que era de 2,8% en el año 2000 y la previsión se elevaba a un 4,4% en el 2030.
Esta enfermedad está fuertemente vinculada al síndrome metabólico (SiMe), a la obesidad, la hipertensión arterial (HTA) y la dislipemia (DLP), que a su vez son factores de riesgo para la enfermedad cardiovascular (ECV) y para el infarto agudo de miocardio (IAM). Debido a estas asociaciones, y a las complicaciones que genera la DM, los pacientes diabéticos suponen un gran gasto sanitario para el presupuesto destinado a la salud en cualquier sociedad. El coste aproximado global a nivel mundial de la DM para el 2015 fue de $673 billones, que corresponde a un 11,6% del gasto estimado en salud a nivel mundial. Se prevee que para el año 2040 esta cantidad será de $802 billones.
La artroplastia total de rodilla (ATR) es un procedimiento de reemplazo articular utilizado actualmente como estándar internacional para el tratamiento de la degeneración articular de la rodilla causada por problemas artrósicos, reumatológicos y de algunas fracturas. Es una de las intervenciones más frecuentes en los servicios de cirugía ortopédica y traumatología.
Cada vez existen más casos de pacientes diabéticos o con alteraciones del metabolismo hidrocarbonado que se someten a este tipo de intervenciones. Se ha descrito que aproximadamente el 52% de pacientes con DM padecen de artrosis y que eventualmente necesitarán algún procedimiento de reemplazo articular. También existe mucha evidencia de que estos pacientes sufren mayor incidencia de complicaciones médicas, infecciosas y relacionadas al implante que los no diabéticos.
Además de los pacientes diabéticos, existe otro grupo de pacientes con alteraciones de la glicemia (hiperglicemia de estrés o diabéticos no conocidos) que están en riesgo de sufrir mayores complicaciones al ser sometidos a cirugía de reemplazo articular.
El propósito de esta tesis doctoral es el estudio de pacientes con alteraciones del metabolismo hidrocarbonado (diagnosticados o no de DM) que son sometidos a ATR. Se estudiará y determinará en que momento del período perioperatorio la hiperglicemia se relaciona con complicaciones post-quirúrgicas (médicas, infecciosas o mecánicas). Se detectará precozmente a aquellos pacientes con DM y con alteraciones de la glicemia (hiperglicemia de estrés o diabéticos no conocidos) durante el período postoperatorio de ATR y a través de una intervención realizada por el médico de atención primaria se estudiará si es posible la disminución de las complicaciones en este grupo de pacientes de riesgo.Each year, the number of diabetic patients and patients with alterations of the hydrocarbon metabolism that undergo total knee arthroplasty (TKA) increases. Approximately 52% of patients with DM suffer from osteoarthritis and will eventually need joint replacement procedure. There is also much evidence that these patients have a higher incidence of medical, infectious, and implant-related complications than non-diabetics. There is another group of patients with altered glycemic levels (stress hyperglycemia or unknown diabetics) who are at risk to suffer greater complications when undergoing joint replacement surgery. The purpose of this doctoral thesis is the study of patients with altered hydrocarbon metabolism (diabetics and non diabetics) who undergo TKA. Our first objective was to determine if there is an association between perioperative hyperglycemia and postoperative complications after one year of follow-up in patients undergoing TKA. We were able to establish that it is during the immediate postoperative period when hyperglycemia (≥126 mg/dl) correlates with medical and infectious postoperative complications. Our second objective was the early detection of patients with unknown changes in hydrocarbon metabolism during the hospitalization period after TKA, and to decrease the incidence of complications in this group of patients. We detected 31.6% of patients with hyperglycemia of stress during the postoperative period of TKA, and we were able to establish that patients who where controlled and treated by the primary care physician after surgery, had lower incidence of systemic medical, infectious and mechanical complications.
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White, Derek A. "Factors affecting changes in joint alignment following knee osteotomy surgery." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63389.pdf.
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Sanchez, Lynda M. "Using the Power of 3 with Total Joint Surgery Patients." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2057.
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The purpose of patient education is to provide patients and their families with the tools needed to care for themselves after discharge from the hospital, but shortened hospital stays, limited health literacy, language, and age can impede the patient's comprehension of the information provided. Researchers have found that the lack of effective patient education is related to 30-day hospital readmissions. The Power of 3 educational tool, designed by Sanchez and Cooknell, addressed the factors that impeded effective patient teaching by using the adult learning theory and low health literacy concepts. The Power of 3 was implemented as a quality improvement project in the Total Joint Center in October 2014. The purpose of this project was to assess the effect of an adult learning-based educational tool on the readmission rates for venous thrombus embolism and infection and on the effect on mobility in total joint surgery patients. This goal was accomplished by performing a retrospective chart review on 90 randomized patients, 45 before and 45 after implementation. The Power of 3 demonstrated a statistically significant change in the length of time a patient remained out of bed on the day of surgery after implementing the educational tool (0.75 hours vs. 1.514 hours, p = 0.0182, CI 95%). In addition, the number of patients that nursing staff documented who were out of bed was also statistically significant on the day of surgery (12 patients vs. 24, p = 0.0461, CI 95%). This educational tool can facilitate patient teaching by addressing language and educational barriers between patients and health care workers.
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Gunaratne, Gorokgodage Don Rajitha. "Laser Osteotomy and Optical Sensing for Advanced Robotic Joint Tissue Surgery." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/86697.
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As part of an industry supported project on robotics for orthopaedic surgery, we investigated new tools for robotic orthopaedics including, lasers for bone cutting, diffuse reflectance spectroscopy (DRS) and autofluorescence spectroscopy (AFS) of animal and human joint tissue. The DRS and AFS work had the aim of creating a sensing system which could be used in laser surgery to differentiate joint tissue.
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Jordaan, Pieter Willem. "Surface replacement of proximal interphalangeal joint (SR-PIPJ) arthroplasty - A case series." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20858.
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Surface replacement (SR) proximal interphalangeal joint replacement consists of a cobalt-chrome alloy component articulating with an ultra-high molecular weight polyethylene component. After experiencing a high rate of subsidence and complications with a pyrocarbon implant, our unit has changed to the cemented SR system in the hope of decreasing these complications. The main aim of this study was to determine whether this change in practice has led to a decrease in subsidence and complications. A retrospective chart review was performed including 43 joints in 28 patients. Subsidence was noted in 26% of the joints and complications in 31% of the joints. Even though subsidence remains a problem, the change in implant has led to a decrease in subsidence and other complications.
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Laurila, née Kostamovaara P. (Päivi). "Pain relief after joint surgery:a clinical study." Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:9514267958.
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Excessive pain after surgery causes many kinds of endocrine, metabolic and inflammatory responses, which may increase postoperative morbidity and mortality - especially among elderly patients. This study evaluated the effect of peripheral and central pain relief techniques after joint surgery.
Intravenously administered doses of 100 mg, 200 mg and 300 mg of ketoprofen decreased the requirement for opioid (fentanyl) in a dose-dependent manner by 38%, 45% and 53%, respectively, compared with a placebo, without any noticeable ceiling-effect, when administered after hip and knee arthroplasty. Patients receiving a 300 mg dose of ketoprofen had significantly lower postoperative pain scores than those receiving a placebo. There were no significant differences in incidences of nausea and vomiting, or in the amount of bleeding between the ketoprofen and placebo groups.
Intravenous doses of 200 mg of ketoprofen, 150 mg of diclofenac, and 120 mg of ketorolac produced similar postoperative pain scores and requirement for opioid (fentanyl) with no intergroup differences in the incidence of nausea and vomiting and in the amount of bleeding, when administered after hip arthroplasty.
The addition of ropivacaine, 1 mg·ml-1, did not decrease the requirement for epidural fentanyl administered via a patient-controlled analgesia device for postoperative pain relief after hip arthroplasty. Both drug infusions provided effective pain relief. The most common adverse effect was pruritus, which occurred in a similar number of patients in both groups.
An interscalene brachial plexus block with ropivacaine decreased the dose of PCA-delivered oxycodone by 78% after arthroscopic shoulder surgery while subacromial bursa blockade with ropivacaine decreased it by only 11 % compared to a placebo during the 20 hour study period. Postoperative pain scores were significantly lowest with a interscalene brachial plexus block.
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Pylios, Theodoros. "A new metacarpophalangeal joint replacement arthroplasty." Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/1004/.
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The metacarpophalangeal joint is vital for hand function. It is frequently affected by rheumatoid arthritis or osteoarthritis and in some cases the diseased joint is replaced with an implant. The past and current metacarpophalangeal joint replacements can be divided into three main categories: hinge implants, flexible implants and surface replacement implants. There is some frustration among hand surgeons as these implants fail in vivo in comparison with the replacement of larger joints such as the hip or knee. The aim of this study was a new design concept for the replacement of the diseased metacarpophalangeal joint. The biomechanics of the diseased rather than the normal metacarpophalangeal joint have been considered during the design requirements procedure. Retrospective analysis of the past and present designs has been considered. Following selection of the concept of the new metacarpophalangeal joint replacement design well established methods like lubrication analysis and contact stress analysis studies, laboratory wear tests and finite element analysis studies have been used for the evaluation of the final design. In this study a new metacarpophalangeal joint replacement has been proposed. The new implant is intended to provide a functional range of motion, sustain the forces that a diseased joint experiences and provide pain relief for the patient. The new proposed metacarpophalangeal joint replacement design tries to combine the benefits of a one piece flexible implant with those of a surface replacement implant design that utilizes the soft layered concept which has been proposed for larger synovial joints
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Stokoe, Susan Marie. "A finger function simulator and surface replacement prosthesis for the metacarpophalangeal joint." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6216/.
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Joint replacement surgery in the treatment of arthritic disease is now commonplace and on the whole very successful. Research into the design and development of prostheses has made major advances since the 1940s resulting in complex devices for almost all articulating joints of the body. In this thesis, a programme of work to design and test a surface replacement prosthesis for the metacarpophalangeal joint is presented. The anatomy and kinematics of the MCP joint are discussed for both normal and abnormal joint function and, based on these considerations, the design of a new surface replacement prosthesis is described. Various materials are explored with respect to their biocompatibility, durability and ease of fabrication with special attention being paid to one material - a new cross linked ultra-high molecular weight polyethylene - which is tested for wear and assessed for durability in long-term prototype tests. A finger function simulator is detailed which was designed and developed during this research programme, and results of tests on bone replicas, Swanson Silastic implants and prototypes of the new design are presented. The simulator can be easily modified to accept any MCP joint prosthesis for bench testing. Finally the stress response of the prototype design is studied using finite element analysis and modifications to the implant design and bone preparation are suggested.
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Hansen, Vicki Ann 1947. "Effects of preoperative group teaching on recovery of patients undergoing joint replacement surgery." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/278015.
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The Purpose of this quasi-experimental study was to test the effects of a multidisciplinary team teaching program on state anxiety, satisfaction with care, and length of hospital stay in patients (N = 38) undergoing hip and knee joint replacement. A multidisciplinary team composed of nurses, a social worker, and a physical therapist presented an one-hour structured teaching program to groups of patients and family members prior to surgery in a 350 bed teaching facility. Control subjects did not receive the structured teaching program. No significant differences in state anxiety, satisfaction with care, or length of hospital stay were found between the experimental subjects (n = 23) who received the teaching program and the control subjects (n = 15) who did not. The project did however, stimulate the development of a formal group teaching program and encouraged collaboration and communication among members of a multidisciplinary team of care providers.
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Santos, Catelli Danilo. "Femoroacetabular Impingement Syndrome and Total Hip Arthroplasty: Joint Biomechanics Before and After Surgery." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38638.
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Surgical interventions on the hip joint have greatly increased over the past decade, with the cumulative cost total hip arthroplasties (THA) alone exceeding $400B/year by 2020. Although positive patient-reported outcomes and satisfaction after THA and hip preservation for cam femoroacetabular impingement (FAI) are among the highest in orthopaedics, a limited number of research has investigated the biomechanics of dynamic activities following-up the surgery. This doctoral thesis examined the kinematics, muscle force component, and hip contact loading in pre- and postoperative patients during the deep squat motion. Specifically, this research: 1) examined muscle strength and pelvic kinematics in asymptomatic FAI, 2) examined lower-limb kinematics and muscle activity in postoperative patients who underwent either THA or FAI correction during a deep squat task, and 3) examined muscle force contributions and hip contact forces (HCF) during dynamic motion in postoperative FAI patients.
First, clinical and medical imaging evaluations classified the participants into three groups: symptomatic FAI, asymptomatic FAI (FAD – participants had the cam deformity, but no pain), and healthy controls. The FAD participants had significantly greater hip extensor strength compared to the FAI and CTRL groups, which allowed them to achieve greater pelvic mobility and squat as deep as the CTRL group.
Second, at the follow-up for the FAI surgery the patients showed increased pelvic ROM during the squat, and weakness associated with hip flexion and hip flexion-with-abduction were associated with postoperative alterations. For the THA follow-up analyses, the patients using a dual- mobility (DM) prosthesis reached an anterior pelvic tilt similarly to the CTRL during the dynamic parts of the squat; however, without returning its neutral tilt at the bottom of the squat, while the single- bearing (SB) prosthesis was associated with excessive hip abduction during the squat.
Third, a generic full-body musculoskeletal model (MSKM) was optimized to allow for the analysis of tasks with a high range of motion (ROM; e.g. deep squat task), which controlled muscle moment arms during the high joint flexions to avoid the model’s motor tendon units (MTU) to penetrate the bony structures and respect the anatomical via points. Simulation performed during gait demonstrated that FAI patients enhance medial-lateral hip stability postoperatively, allowing reduced dynamic forces of the muscles associated with the sagittal aspect of the gait due to a less compensatory strategy to stabilize the hip joint. Furthermore, simulations performed during deep squat showed a higher anterior pelvic tilt in postoperative FAI patients as a ‘restore to native’ mechanism once the cam-deformity was no longer present. Increased semimembranosus force was linked to higher vertical HCF and total magnitude.
The outcomes of this research include findings for gait and squat analyses that provide a better understanding of the pelvic mobility and hip muscle forces in hip diseases. In silico models can improve biomechanical assessment of postoperative patients in order to quantify surgical effectiveness and support clinicians in making subject-specific case decisions. The contributions also lay on the assertion of helping us to formulate future research directions in biomechanics applied to the orthopaedics field.
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Iyengar, Reethi. "Factors Associated with Hospital Entry into Joint Venture Arrangements with Ambulatory Surgery Centers." VCU Scholars Compass, 2011. https://scholarscompass.vcu.edu/etd/2436.
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This study presented an empirical analysis of the key market, regulatory, organizational, operational and financial factors associated with hospital entry into joint venture (JV) arrangements with Ambulatory Surgery Centers (ASCs) as examined through the framework of resource dependency theory complimented with neo-institutional theory. This study used a cross sectional design to examine hospitals that entered into a joint venture arrangement with ASCs in 2006 and 2007. The data for this study were drawn from five main sources: the American Hospital Association Annual Survey (AHA), the Area Resource File (ARF), the CMS (Center for Medicare and Medicaid Services) minimum dataset, the National Legislative Assembly Website and the CM case-mix files. Descriptive analysis and multivariate logistic regression were performed to examine the association of various factors in this study. The study found that market factors such as unemployment rate and percentage of elderly were strongly associated with the hospitals decision to joint venture with ASCs. Also organizational size (measured by bed size) was a significant factor in these decisions. Other factors which showed a marginal significance were Herfindahl-Hirschman Index, number of ASCs, certificate of need laws, ownership status, and operating expense per adjusted discharge of the hospital. This research project sheds light on joint venture arrangements between hospitals and ASCs at a very opportune time. In light of the new Health Reform Legislation, studying hospital-ASC joint ventures is very important. For hospitals and ASCs, and their collaborative interests such as joint ventures, Accountable Care Organizations (ACO’s) could either provide incentives to help improve quality of care to patients or stint on needed care by making them focus narrowly on higher margin services (Fisher and Shortell 2010; Shortell and Casalino 2010). Since policy measures should encourage the first and not the second outcome, it is important to have a transparent performance measurement system that can win the confidence of the provider organizations such as hospitals and ASCs. Lacking which, it may discourage joint venture arrangements between hospitals and ASCs in future.
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Mahomed, Aziza. "Properties of elastomers for small-joint replacements." Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/295/.
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Silicones are used to manufacture finger and wrist joints. However these joints have fractured prematurely in vivo. There is a lack of literature on the mechanical properties of silicones. The aim of this thesis was to investigate the viscoelastic and related properties of elastomers such as silicones and polyurethanes (suggested as a possible substitute for silicones in the implants) and to relate the properties to how an implant may perform in vivo. The viscoelastic properties of medical-grade silicones and Elast-Eon\(^{TM}\)3 were found to depend on frequency in compression. Above a certain frequency, the silicones appeared to undergo a transition from the rubbery to the glassy state. There is a danger that this could lead to the creation of fracture surfaces. The viscoelastic properties of the silicones were not significantly affected by the temperature; pre-treatment of specimens had no appreciable effect on the results. When the viscoelastic properties were measured in tension, there was a significant difference between the properties measured in tension and compression. Accelerated aging significantly increased the moduli of Elast-Eon\(^{TM}\)3, which is of some concern. The cross-link densities of the silicones were measured using a solvent swelling technique and the Flory-Rehner equation. The results showed that this method is useful as an approximate model.
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Kamucha, George N. "A non-invasive registration technique in hip-joint replacement surgery using laser radar imaging." Kassel : Kassel Univ. Press, 2003. http://deposit.d-nb.de/cgi-bin/dokserv?idn=970519281.
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Bills, Paul J. "The development of a geometric methodology for the determination of volumetric wear in total joint replacements & development of a total knee replacement joint using new and novel measurement techniques." Thesis, University of Huddersfield, 2007. http://eprints.hud.ac.uk/id/eprint/2020/.
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Total joint replacement is one of the most common elective surgical procedures performed worldwide, with an estimate of 1.5 million operations performed annually. It has long been recognised that wear analysis of total joint replacements is an important means in determining failure mechanisms, functionality and improving longevity of these devices. The standardised method for assessing wear volumes in such joints is through gravimetric means and it has been shown that this method is a useful tool for indicating simulated wear volumes. This method is, however, of little value when considering the case of a clinically explanted bearing surface for which, by definition, there is no ‘pre-wear’ data. The purpose of this thesis is to present a co-ordinate measuring machine (CMM) based technique for assessing the volumetric material loss in total joint replacement joints and to establish its effectiveness. To this end uncertainty calculations are completed for the specific case of orthopaedic component measurement. In this thesis methods have been developed in this thesis for measurement of in vitro wear of total knee replacement bearings and a number of knee joint simulator tests have been completed and their results discussed. An initial test investigating the possible use of metal-on-metal bearings for total knee replacement is described. A test profile for simulation of deep squat is developed, a simulator test completed and the results discussed. An adapted version of the developed CMM measurement method is further adapted and developed for measurement of clinical wear from retrieved bearings and the implications of this capability are examined and discussed. In tandem with this methods are developed for the mapping of wear location and component form deviation and the implications that this has for manufacturing control and wear potential is discussed at length. Overall future developments and work are explored.
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Wilson, David Robert. "Three-dimensional kinematics of the knee." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320163.
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Mina, Rina M. D. "Effectiveness of Dexamethasone Iontophoresis for Temporomandibular Joint Involvement in Juvenile Idiopathic Arthritis." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1305892368.
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Ivanov, Alexander. "Development, validation and clinical application of finite element human pelvis model." University of Toledo Health Science Campus / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=mco1213734675.
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Sun, Dan. "Abrasion-corrosion of cast CoCrMo in simulated hip joint environments." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/67337/.
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Metal-on-metal (MoM) hip joint replacements have been increasingly used for younger and more active patients in recent years due to their improved wear performance compared to conventional metal-on-polymer bearings. MoM bearings operate at body temperature within a corrosive joint environment and therefore are inevitably being subjected to wear and corrosion as well as the combined action of tribo-corrosion. Issues such as metal sensitivity/metallosis associated with high levels of metal ion release triggered by the wear and corrosion products remain critical concerns. During the past few decades, significant research has been conducted into understanding the wear/lubrication mechanisms within the MoM hip joints in order to improve their performance and thereby prolonging their life. However, not much attention has been given to the combined effect of wear and corrosion of such devices in the hip joint environment, in addition, the role of third body particles and the effects of proteins have not been well understood. In this work, a systemic approach is presented for the first time for the mapping of abrasion and tribo-corrosion performance of a cast CoCrMo (F75) in simulated hip joint environments. The effects of third body particles have been studied in the MoM context using 4 μm SiC, 1 μm and 300 nm Al2O3, as well as sub-micron BaSO4. Modified tribo-testers (micro-abrasion, nanoindenter/scratching) incorporating a novel electrochemical cell have been used to monitor the abrasion-corrosion behaviour of the alloy in situ. The effects of solution chemistry, abrasives size / concentration and presence of proteins on the wear / corrosion level, wear-corrosion mechanisms, and the depassivation/repassivation kinetics of the CoCrMo have been explored. A variety of surface and sub-surface characterization techniques have been employed to identify the microstructual wear mechanism interactions. Results show that the change of protein concentration (0, 25% and 50% bovine serum) and pH (pH 7.4 and pH 4.0) of the test solutions can significantly influence the protein adsorption behaviour, which subsequently influence the wear rates (synergy), wear mechanisms as well as the wear-induced corrosion currents of the CoCrMo. For abrasion-corrosion tests, reducing abrasive size from 4 μm to 300 nm and/or abrasive volume concentration from 0.238 vol% to 0.006 vol% results in different abrasion-corrosion wear mechanisms (rolling or grooving abrasion) and the average wear-induced corrosion currents show a linear correlation with wear rates for 4 μm and 1 μm abrasives. For low volume concentration (< 0.03 vol%) slurries containing bovine serum, organo-metallic conglomerates have been found within the wear scars. These conglomerates help separate the surfaces, impose less damage to the surface passive film and polish the wear scars through a chemical mechanical polishing mechanism. In addition, tribo-corrosion tests at micro-/nano- scales reveal the effects of single abrasive particle on the surface/sub-surface microstructual change. This investigation has revealed the nanoscale wear mechanisms that generate nanoscale wear debris, the mechanical mixing of the surface nanostructure with adsorbed denatured protein and also the slip/dislocation systems that are present near and on abraded surfaces that are likely to disrupt the surface passive films. The findings give a better understanding of the evolution of the sub-surface nanocrystalline structures and tribo-layers formation seen for the retrieved implants. This near surface nanostructure layer and phase transformation might offer better wear resistance through these inherent self-protecting mechanisms (i.e. increased hardness); conversely, it may become the precursors to debris ejection and enhanced ion-release into the CoCrMo joints. This work established an experimental technique that gives greater understanding of the tribocorrosion behaviour of cast CoCrMo in simulated hip joint environments. In particular, the roles of third body abrasive particles and proteins have been addressed, which are relevant to clinical applications. The material multi-scale wear mechanisms as well as the evolution of the surface / subsurface microstructures and tribo-layers have been elucidated, which provide new insights into the in vivo wear mechanisms of CoCrMo. The findings of this study may provide some important indications for improved MoM joint materials, design, manufacture and evaluation.
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Morier, Rita. "Dynamic joint mechanics as an objective clinical measure of ankle function." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61268.
Full textAbstract:
The purpose of the work contained in this thesis was to investigate whether experimental paradigms based on the system identification approach are an effective clinical assessment tool. This was accomplished by conducting two companion studies: a reliability study on a group of fifteen control subjects and a case study of an individual who had sustained a unilateral undisplaced ankle fracture. The data collected in both studies included ankle angular position, torque, and Tibialis Anterior and Triceps Surae electromyograms. From these data, measures of both static (e.g. range of motion) and dynamic (e.g. estimated elastic stiffness) joint function, were obtained.A number of clinically relevant variables (plantarflexion MVC, dorsiflexion MVC, range of motion, passive torque, K offset, low K region, and the intercept of the K-absolute torque relation) were shown to be reliable. In addition, the results of the case study demonstrated that it would be feasible to use these experimental procedures and analytic methods on individuals who have sustained orthopedic trauma. Finally, certain variables (the K offset, the slope and intercept of the K-torque relation, and a low stiffness region) appeared to be sensitive to the clinical changes associated with orthopedic pathology.
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Kamucha, George N. [Verfasser]. "A non-invasive registration technique in hip-joint replacement surgery using laser radar imaging / George N. Kamucha." Kassel : Kassel Univ. Press, 2003. http://d-nb.info/970519281/34.
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Parker, Trevor Wayne. "Functional outcome and complications after treatment of moderate to severe slipped upper femoral Epiphysis with a modified Dunn procedure." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5447.
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Andreou, Antonios. "The influence of facet joint geometry on lumbar segmental kinematics : an ex-vivo & in-vivo study." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20240.
Full textAbstract:
It has long been postulated that the facet joint geometry (FJG) has an important influence on lumbar segmental motion. Although their sagittal orientation has been described in detail, there are very few studies describing the three-dimensional (3D) FJG. None correlates the latter to segmental kinematics. In view, we developed a method to quantify 3D FJG and compared the results to segmental kinematics.In the ex-vivo set-up, facets of individual cadaveric vertebrae taken from a previous biomechanical. study were digitized using a 3D morphometer and the geometry of the facet joints in respect to the vertebra's local coordinate system was quantified. In the in-vivo set-up, re-recruited subjects from a previous kinematic study had a MRI of their lumbar spine. The images were digitized and the facet joint's 3D geometry was evaluated. The two methods used for FJG measurements were validated. Kinematic data derived from both previous studies was correlated with their respective FJG.
We did not find a significant influence of the FJG or tropism on lumbar segmental kinematics. Different coupling patterns were measured in the ex-vivo and in in-vivo experiments. This is likely due to the absence of muscle activity in the cadaveric specimen. Future in-vivo studies should be done with simultaneous muscle activity recording to better understand the coupling patterns. Studying FJG in defined spinal pathologies may render valuable information on the etiology of spinal diseases.
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Au, Yeung Siu-hong, and 歐陽紹康. "Health-related quality-of-life outcome after elective total joint arthroplasty in Hong Kong Chinese patients." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31971441.
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Cortez, Andre Luis Vieira. "Avaliação radiografica da posição condilar em pacientes submetidos a osteotomia Le Fort I para avanço maxilar." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289686.
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Orientador: Luis Augusto PasseriTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Foi realizado um estudo radiográfico prospectivo avaliando a angulação e o posicionamento condilar, por meio da radiografia submento-vértice e da tomografia convencional da articulação temporomandibular (ATM). Para o estudo, foram selecionados onze pacientes, que procuraram atendimento na Área de Cirurgia e Traumatologia Buco-Maxilo-Faciais da Faculdade de Odontologia de Piracicaba ¿ Unicamp, para correção cirúrgica de deformidade dentofacial. Todos estavam em tratamento ortodôntico preparatório e possuíam o mesmo diagnóstico de deficiência ântero-posterior de maxila, sendo o planejamento cirúrgico definido, após análise facial, análise dos modelos de estudo e traçados cefalométricos, como a osteotomia Le Fort I para avanço maxilar. As imagens radiográficas foram obtidas nos períodos pré-operatório imediato, pós-operatório imediato (1-2 semanas) e pós-operatório tardio (mínimo de 6 meses). Foram mensuradas a angulação axial dos côndilos e a medida linear sobre os cortes tomográficos, dos espaços articulares posterior, superior e anterior para as posições de máxima intercuspidação habitual e repouso, e a máxima abertura bucal, nos três períodos. As imagens das tomografias, juntamente com os traçados, foram digitalizadas e mensuradas por meio de um programa de computador (UTHSCSA Image Tool 3.0), após a sua devida calibração. Os dados foram colhidos três vezes, com um intervalo de no mínimo 24 horas e, então, a média submetida à análise estatística (ANOVA ¿ nível de significância de 5%). Os resultados não foram significativos para as medidas lineares dos espaços articulares em nenhum período, bem como para a medida angular axial dos côndilos. Na máxima abertura bucal, ocorreu diferença significativa (diminuição da abertura) para o período pós-operatório imediato, em ambos os lados. Concluiu-se que a osteotomia Le Fort I para avanço maxilar não causou alterações significativas na posição condilar nesse grupo de pacientes avaliados
Abstract: It was realized a prospective radiographic study of the angulation and position of the mandibular condyle, by means of submento-vertex radiograph and conventional tomography of the temporomandibular joint (TMJ). For the study, it was selected eleven patients who were referred to the Division of Oral and Maxillofacial Surgery of Piracicaba School of Dentistry ¿ Unicamp, for surgical correction of dentofacial deformity. All patients were under preparatory orthodontist therapy to surgical procedure and had the same diagnoses of anterior-posterior deficiency of maxilla, in which the final surgical goal, after facial analysis, model analysis and predictive radiographic tracings, was the Le Fort I osteotomy to advance the maxilla. The radiographic images were taken at the immediate preoperative, immediate post-operative (1-2 weeks) and late post-operative (minimum of 6 months). It was measured the axial angulation of the condyles and the linear measurements for the tomographic images, over the posterior, superior and anterior articular spaces in the maximal intercuspation and rest position, and the maximal opening, for the three periods. Tomographic images with the tracings were digitized and measured by means of a computer software (UTHSCSA Image Tool 3.0), after its adequate calibration. Data analysis was collected three times, with a minimum of 24 hours between them and, after that, the mean value was submitted to statistical analysis (ANOVA ¿ 5% of significance). The results were not statistically significant for the linear measurements of the articular spaces in any of the periods, as well as for the axial angular measurements of the condyles. In the maximal opening, there was significant difference (decrease of opening) for the immediate post-operative period, for both sides. In conclusion, Le Fort I osteotomy for maxillary advancement did not cause any significant changes in this specific group of patients evaluated.
Doutorado
Cirurgia e Traumatologia Buco-Maxilo-Faciais
Doutor em Clínica Odontológica
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Pizzol, Karina Eiras Dela Coleta. "Alterações do tecido mole, espaço faríngeo e estabilidade após avanço maxilo-mandibular xom rotação anti-horária e prótese total de ATM /." Araraquara : [s.n.], 2008. http://hdl.handle.net/11449/104485.
Full textAbstract:
Orientador: João Roberto GonçalvesBanca: Ary dos Santos-Pinto
Banca: Roberto Henrique Barbeiro
Banca: Darceny Zanetta Barbosa
Banca: Terumi Okada
Resumo: Este estudo avaliou a resposta do tecido mole, do espaço faríngeo e a estabilidade após avanço maxilo-mandibular com rotação anti-horária e reconstrução da ATM com próteses totais articulares do tipo TMJ Concepts system®. As mudanças cirúrgicas e pós-cirúrgicas foram analisadas utilizando-se telerradiografias laterais. Com o movimento cirúrgico, houve redução do ângulo do plano oclusal (14,9 ± 8,0°) e aumento do espaço aéreo faríngeo - PASnar (4,9mm). A região anterior da maxila moveu-se para a frente e para cima enquanto a porção posterior, para a frente e para baixo. A mandíbula avançou, e sofreu rotação no sentido anti-horário. No período pós-cirúrgico, a maxila apresentou alterações mínimas no plano horizontal, enquanto todas as medidas mandibulares permaneceram estáveis. A postura da cabeça (OPT/NS) mostrou flexão imediatamente após a cirurgia e extensão em longo prazo, enquanto a curvatura cervical (OPT/CVT) não apresentou mudanças. Os resultados cirúrgicos mostraram ainda aumento das distâncias entre a terceira vértebra cervical (C3) e o mento e desta com o hióide, permanecendo estáveis durante o período de observação. A distância entre o osso hióide e o plano mandibular reduziu durante e após a cirurgia. Já a resposta do tecido mole evidenciou diferentes razões entre tecido duro/mole nos pacientes com e sem genioplastia. As mudanças horizontais na morfologia do lábio superior após avanço, impacção da maxila, sutura em VY e sutura da base alar mostraram maior movimento do que as mudanças observadas em tecido duro. O avanço maxilo-mandibular com rotação anti-horária do plano oclusal associado a próteses totais de ATM (TMJ Concepts system®) mostrou-se estável durante o período de observação. O espaço aéreo faríngeo aumentou... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This study evaluated stability, soft tissue response and oropharyngeal airway space changes after maxillo-mandibular advancement and counter-clockwise rotation with TMJ reconstruction using TMJ Concepts system® total joint prostheses. Lateral cephalograms were analyzed to estimate surgical and post surgical changes. During surgery, the occlusal plane angle decreased 14.9 ± 8.0° and the retroglossal airway space (PASnar) increased 4.9mm. The anterior region of maxilla moved forward and upward while the posterior nasal spine moved downward and forward. The mandible changed forward and rotated in a counter-clockwise direction. At long-term follow-up evaluation the maxilla showed minor horizontal changes, while all mandibular measurements remained stable. Head posture (OPT/NS) showed flexure immediately after surgery and extension long-term post surgery, while cervical curvature (OPT/CVT) had no significant changes. Surgery increased the distances between the third cervical vertebrae (C3) and menton, and C3 and hyoid, remaining stable afterwards. The distance from the hyoid to the mandibular plane decreased during surgery and in the longest follow-up. Soft tissue response indicated different hard/soft tissue ratios between patients with or without genioplasties. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement, than observed in hard tissue. TMJ Concepts total joint prostheses associated with maxillo-mandibular advancement and counter-clockwise rotation showed to be stable during the follow-up observation period. Immediate increase in oropharyngeal airway dimension, was influenced by post-surgical changes in head posture but remained stable over the follow-up period. Soft tissue changes showed a known predictable response.
Doutor
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Irvine-Smith, Gregory Stuart. "A biomechanical investigation into the effects of decompressive surgery, on the stability of the lumbosacral joint in the dog." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/30034.
Full textAbstract:
The primary objective of this biomechanical study was to investigate the effect of decompressive surgery, specifically dorsal laminectomy and discectomy, on the stability of the lumbosacral joint in the dog. Different size laminectomies were compared with respect to their effect on lumbosacral stability. A total of eighteen lumbosacral motion units were collected from cadavers and divided into three groups. Group 1 was a control group and received no modification, Group 2 specimens received mini-dorsal laminectomies and discectomies (lamina of L7 caudal to the dorsal spinous process excised, lamina of S1 not affected) while Group 3 specimens received standard dorsal laminectomies and discectomies (75% of L7 lamina and 50% of S1 lamina excised). All specimens were potted in aluminium tubing and mounted in a four-point bending jig and tested in a load cell. Specimens were stressed to 21° in dorsiflexion and ventroflexion. The relevant surgical modification was then performed and the specimens re-tested to 21° in dorsiflexion and ventroflexion. All specimens were then tested to failure in ventroflexion. Force and angular displacement was recorded and used to obtain load-deformation curves for each specimen (5 curves for each specimen). From the load-deformation curves the stiffness (gradient of the graph) was determined at three set angles of deflection. These points were 6°-8°, 12°-16° and 18°-20°. The percentage change in stiffness for each specimen in both dorsiflexion and ventroflexion was obtained. Peak force at failure and angular deformation at failure were obtained when tested to failure in ventroflexion. When examining the overall stiffness of the specimen (dorsiflexion and ventroflexion and all angles of deflection) mini-dorsal laminectomy was shown to result in a 48.3% reduction in stiffness (P < 0.001) while standard dorsal laminectomy and discectomy resulted in a 59.8% reduction in stiffness (P < 0.001). These results were statistically significant. The difference between the two different types of laminectomies could be described as approaching significance (P=0.066). Larger group size would be required to determine whether this is in fact statistically significant Dorsal laminectomy combined with discectomy does have an effect on the stability of the lumbosacral joint. This may contribute to the relatively high recurrence rate following surgical treatment of degenerative lumbosacral stenosis especially in large breed highly active dogs. The study provides further support for decompressive surgery combined with a stabilisation technique when treating degenerative lumbosacral stenosis. It also provides potential support for the use of mini-dorsal laminectomies.Dissertation (MMedVet)--University of Pretoria, 2009.
Companion Animal Clinical Studies
unrestricted
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Quinci, Federico. "Towards a micromechanical insight into the visco-dynamic behaviour of UHMWPE for the modelling of knee joint replacement systems." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/363765/.
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Considerable progress has been made in understanding implant wear and developing numerical models to predict certain aspects of wear for new orthopaedic devices. However, any model of wear could be improved through a more accurate representation of the biomaterial micromechanics, including time-varying dynamic and inelastic behaviour such as viscous and plastic deformation as well as any history-dependent evolution of its microstructural properties. Under in-vivo conditions, the contact surface of the UHMWPE tibial insert evolves as a result of applied loads and complex multidirectional motions of the femoral component against it. Overt time, severe inelastic deformations and damage mechanisms occur and ultimately lead to wear. This process is accompanied by the release of UHMWPE debris in the surrounding tissues with the direct consequences of triggering an in ammatory response that leads to osteolysis and subsequently periprosthetic implant loosening. In that case a revision surgery is required. Motivated by these facts, the current research effort has been motivated by the need to gain a mechanistic insight into the micromechanical mechanisms associated with wear of UHMWPE in knee arthroplasty. To this end, two main lines of focus have been followed in this work. One line of focus concerns the inelastic mechanisms of deformation such as creep and plasticity since they are critical in altering the contact properties of the articulating surface of UHMWPE components, leading to damage and formation of wear debris. Therefore, the relative contributions of elastic, creep, and plastic deformations on the contact area, and so contact pressure has been investigated through different numerical techniques. Additionally, contact pressure is a critical input parameter of computational wear algorithms, and it is therefore essential to establish the nature of and quantify the interplay between contact pressure, contact area, creep and plastic deformations. What are the consequences of neglecting creep deformations on wear predictions? A first approach to investigate these aspects consisted in conducting a series of physicallybased finite element analyses replicating the mechanical characteristics and operating conditions of an AMTI Knee Simulator. Experimental creep testing on a unicondylar knee replacement system in a physiologically representative context was simulated. In both studies, linear elastic, plastic and time-varying visco-dynamic properties of computational models were benchmarked using literature data to predict contact deformations, pressures and areas. Results indicate that creep deformations have a significant effect on both experimental and simulated contact pressures at the surface of the UHMWPE tibial insert. The use of a purely elastoplastic constitutive model for UHMWPE lead to compressive deformations of the insert which were in general smaller than those predicted by a creep-capturing viscoelastic model. At high compressive loads, inelastic deformation mechanisms dominate the mechanical response of UHMWPE components by altering the surface geometry (i.e. contact area), and therefore the contact pressure. The second line of focus concerns the study of the role of transient and permanent polymer chain realignment during multidirectional sliding, and its potential correlation to wear. The main working hypothesis is that the evolution of the UHMWPE microstructure during multidirectional pin-on-disk (POD) tests can provide information on possible correlations between wear, sliding track characteristics and the mechanics of UHMWPE. Therefore, finite element-based POD tests were used to investigate the effects of motion paths in simulated multidirectional sliding motions on metrics related to the mechanical response of UHMWPE, with particular attention to evolution of molecular chain realignment. For this purpose, the concept of anticoaxiality as a measure of molecular chain realignment (or anisotropy) has been introduced. The concept of anticoaxiality as a measure of molecular chain realignment (or anisotropy) was introduced to quantify the deviation from mechanical isotropy of UHMWPE microstructure. Results from these metrics support the hypothesis that multidirectional sliding as well as long sliding distances produced microstructural changes in UHMWPE, resulting in an enhanced likelihood of material damage, and so wear.
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Barros, Luciano Pereira de [UNESP]. "Estudo experimental e comparativo entre as técnicas de pino em cavilha com fio fluorcarbono monofilamentar e colocefalectomia para estabilização coxofemoral em cães." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/89093.
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barros_lp_me_jabo.pdf: 894125 bytes, checksum: 291c2da790713462f8653ad7c1ce412f (MD5)No presente trabalho comparou-se, experimentalmente, duas técnicas: a estabilização coxofemoral com pino em cavilha ou “toggle pin” e a colocefalectomia. Foram utilizados 16 cães, machos ou fêmeas, distribuidos em dois grupos: o de Pino (GP) e o Colocefalectomia (GC), os quais foram separados em 4 subgrupos: animais com peso superior e, inferior ou igual a 15 kg. Avaliou-se o tempo de cirurgia, o grau de atrofia muscular, a deambulação e a dor, além de presença ou não de alterações radiograficas da articulação. O tempo cirúrgico, devido a maior complexidade da técnica do pino, foi menor no GC. A técnica do GP foi melhor quanto à recuperação do membro, apresentando menor atrofia muscular
On the present assay was compared experimentally between two techniques: hip joint stabilization with toggle pin and hip joint stabilization with head of the femur. Were used 16 dogs, female or male, distributed in 2 groups: the pin group (GP) and head of the femur group (GC), the groups were distributed in 4 subgroups: by weight equal, more or less than 15kg. Evaluating the time of surgery, and the notch of muscle atrophy, wander around the pain and also with the presence or not of alterations on the joint radiograph. The time of surgery is longer in the technique of pin than on the group GC, because the technique of pin had more complexity. So the technical of the group GP was better on the recovery member, which presented less muscle atrophy
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Pizzol, Karina Eiras Dela Coleta [UNESP]. "Alterações do tecido mole, espaço faríngeo e estabilidade após avanço maxilo-mandibular xom rotação anti-horária e prótese total de ATM." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104485.
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pizzol_kec_dr_arafo.pdf: 688008 bytes, checksum: 35e9164526c1e0e9be53fc6134f7ea9a (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este estudo avaliou a resposta do tecido mole, do espaço faríngeo e a estabilidade após avanço maxilo-mandibular com rotação anti-horária e reconstrução da ATM com próteses totais articulares do tipo TMJ Concepts system®. As mudanças cirúrgicas e pós-cirúrgicas foram analisadas utilizando-se telerradiografias laterais. Com o movimento cirúrgico, houve redução do ângulo do plano oclusal (14,9 ± 8,0°) e aumento do espaço aéreo faríngeo - PASnar (4,9mm). A região anterior da maxila moveu-se para a frente e para cima enquanto a porção posterior, para a frente e para baixo. A mandíbula avançou, e sofreu rotação no sentido anti-horário. No período pós-cirúrgico, a maxila apresentou alterações mínimas no plano horizontal, enquanto todas as medidas mandibulares permaneceram estáveis. A postura da cabeça (OPT/NS) mostrou flexão imediatamente após a cirurgia e extensão em longo prazo, enquanto a curvatura cervical (OPT/CVT) não apresentou mudanças. Os resultados cirúrgicos mostraram ainda aumento das distâncias entre a terceira vértebra cervical (C3) e o mento e desta com o hióide, permanecendo estáveis durante o período de observação. A distância entre o osso hióide e o plano mandibular reduziu durante e após a cirurgia. Já a resposta do tecido mole evidenciou diferentes razões entre tecido duro/mole nos pacientes com e sem genioplastia. As mudanças horizontais na morfologia do lábio superior após avanço, impacção da maxila, sutura em VY e sutura da base alar mostraram maior movimento do que as mudanças observadas em tecido duro. O avanço maxilo-mandibular com rotação anti-horária do plano oclusal associado a próteses totais de ATM (TMJ Concepts system®) mostrou-se estável durante o período de observação. O espaço aéreo faríngeo aumentou...
This study evaluated stability, soft tissue response and oropharyngeal airway space changes after maxillo-mandibular advancement and counter-clockwise rotation with TMJ reconstruction using TMJ Concepts system® total joint prostheses. Lateral cephalograms were analyzed to estimate surgical and post surgical changes. During surgery, the occlusal plane angle decreased 14.9 ± 8.0° and the retroglossal airway space (PASnar) increased 4.9mm. The anterior region of maxilla moved forward and upward while the posterior nasal spine moved downward and forward. The mandible changed forward and rotated in a counter-clockwise direction. At long-term follow-up evaluation the maxilla showed minor horizontal changes, while all mandibular measurements remained stable. Head posture (OPT/NS) showed flexure immediately after surgery and extension long-term post surgery, while cervical curvature (OPT/CVT) had no significant changes. Surgery increased the distances between the third cervical vertebrae (C3) and menton, and C3 and hyoid, remaining stable afterwards. The distance from the hyoid to the mandibular plane decreased during surgery and in the longest follow-up. Soft tissue response indicated different hard/soft tissue ratios between patients with or without genioplasties. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement, than observed in hard tissue. TMJ Concepts total joint prostheses associated with maxillo-mandibular advancement and counter-clockwise rotation showed to be stable during the follow-up observation period. Immediate increase in oropharyngeal airway dimension, was influenced by post-surgical changes in head posture but remained stable over the follow-up period. Soft tissue changes showed a known predictable response.
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Hon, Suet, and 韓雪. "Effectiveness of multi-factorial interventions in reducing post-operative delirium among elderly patients with hip fracture." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193053.
Full textAbstract:
According to the World Health Organisation, hip fracture among elderly people is a global public health problem, with 1.7 million cases worldwide in 1991, a figure due to the aging population and believed likely to increase. Post-operative delirium is a common complication following hip-fracture surgery, and occurs in 25% to 65% of cases (Gustafson 1988). It not only affects the rehabilitation progress of the elderly, but also prolongs hospitalisation, which in turn increases the financial burden on the government.
There are different ways of managing post-operative delirium among the elderly, including pharmacological and multifactorial interventions and education programmes. However, there is no standard nursing management of post-operative delirium in Hong Kong, and this affects both patient care and nursing standards. According to the National Institute for Health and Clinical Excellence (2011), multifactorial intervention is cost-effective and an effective method of reducing postoperative delirium, where nurses play an important role as gatekeepers, and thus allow such intervention to be introduced into the clinical setting. With this in mind, translational nursing research was performed by a review of four studies, to introduce the concept of multifactorial intervention to nurses, to formulate the implementation for the intervention, and finally to obtain feedback from colleagues.published_or_final_version
Nursing Studies
Master
Master of Nursing
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Akhavan, Jaleh. "The effect of a dyadic intervention on self-efficacy, physical functioning and anxiety in older adults post joint replacement surgery." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1761867951&sid=7&Fmt=2&clientId=48051&RQT=309&VName=PQD.
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Shi, Xiaojian, and 施曉健. "Reconstruction of ankylotic and resected mandibular condyle by transport distraction osteogenesis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39634486.
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Nathan, M. "Post-menisectomy atrophy of the quadriceps femoris : the role of the pneumatic tourniquet and the effects of exercise rehabilitation." Thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/26341.
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Yeung, Kwok Tai Cathay. "Effect of total knee replacement design and surgical technique on patello-femoral joint performance : an explicit finite element study." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/64812/.
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There is an increasing demand for total knee replacements (TKR). Young patients are placing increasing functional demands on modern TKR. Clinical experience has also shown the need for high flexion in patients after TKR. In this study, assessment of TKR performance subjected to deep knee bend was investigated. Patellar resurfacing in TKR is assumed to release pain and restore knee function. Despite the recent advance and success in TKR operation, patellar resurfacing has been associated with an increase in complications at the patello-femoral joint, and hence revisions following TKR. Complications include poor tracking, instability, wear, loosening and fractures. These complications have been attributed in part to the component design features (e.g. sagittal radius, depth, and orientation of the trochlear groove of the femur and the geometry of the patellar component surface) and surgical technique (e.g. component alignment and ligament balance). However, the influence of these factors on the overall performance of TKR has not been investigated extensively. The objective of the study was to determine the variation of patellar kinematics (tracking motion) and contact mechanics (contact force, area, pressure and stress) induced by component design and surgical technique. A three-dimensional finite element (FE) model of a PFC-Sigma TKR, including the tibio-femoral and patello-femoral joints was developed. Explicit FE analysis was used to simulate TKR under a deep knee flexion. The models predicted substantial increase in patellar pressure and stress with nonconforming patello-femoral articulating surfaces. Femoral groove orientation affected patellar tracking and contact mechanics. Extending femoral groove distally reduced patello-femoral contact stress at high flexion angles. Also, externally rotating the femoral component and adjusting the line of action of quadriceps pull would be beneficial by reducing patellar lateral force. The FE model used in the current study provided insight into the effect of component design parameters and surgical technique on patellofemoral kinematics and contact mechanics.
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Langie, Renan Cavalheiro. "Artroplastia biconvexa de Puricelli em articulação temporomandibular de ovelhas : avaliação da estabilidade da técnica cirúrgica, da funcionalidade articular e do peso corpóreo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/56461.
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Introdução: As patologias que afetam a articulação temporomandibular (ATM) compõem um grupo heterogêneo e são genericamente conhecidas como desordens temporomandibulares (DTM). Nos casos de patologias proliferativas ou ablativas nesta articulação, há indicação de intervenção cirúrgica. As técnicas de reconstrução da articulação temporomandibular são indicadas quando há destruição parcial ou completa dos tecidos articulares. A técnica de artroplastia biconvexa de Puricelli propõe a reconstrução da ATM por meio da instalação de duas superfícies convexas de polimetilmetacrilato, manipuladas durante o ato cirúrgico. Uma das superfícies é localizada na parede posterior e superior da fossa mandibular e a outra no segmento mandibular, ficando as duas superfícies convexas em contato entre si em um ponto. A técnica proposta por Puricelli em 1995 tem sido aplicada em pacientes desde o ano de 1978, apresentando sucesso clínico nos casos operados. Objetivos: Os autores buscam avaliar a técnica do ponto de vista de seu controle radiográfico, desempenho funcional, e do efeito de sua realização sobre o peso corpóreo, por meio de sua aplicação em um modelo animal. A amplitude máxima dos movimentos de abertura bucal e a lateralidade bilateral da mandíbula foram medidas e comparadas entre os diferentes tempos e grupos do estudo. A avaliação macroscópica e radiográfica da estabilidade das superfícies convexas de polimetilmetacrilato na ATM reconstruída foi verificada nos diferentes períodos pós-operatórios. A avaliação do peso dos animais foi realizada por meio da comparação entre o peso corpóreo pré-operatório e nos diferentes períodos pós-operatórios. Metodologia: Foi realizado um estudo experimental em modelo animal, controlado e parcialmente cego. A técnica de artroplastia biconvexa de Puricelli foi realizada na ATM esquerda de ovelhas. O grupo controle foi composto por quatro animais, dois para cada tempo do estudo. O grupo teste, o qual foi submetido à técnica, foi composto por dez animais, cinco para cada tempo do estudo. O projeto utilizou quatorze animais. Foram realizadas análises de estabilidade da reconstrução, da funcionalidade articular e do peso em dois tempos pós-operatórios, 45 e 90 dias. Resultados: Em todos os animais submetidos à técnica de artroplastia biconvexa de Puricelli, a reconstrução da ATM apresentou estabilidade macroscópica e radiográfica nos períodos pós-operatórios avaliados. Nos grupos teste (T45 e T90) e controle (C45) não se observou diferença estatística quanto à amplitude da abertura bucal máxima e lateralidade esquerda quando comparado nos três tempos avaliados (T0= pré-operatório, T1= pós-operatório imediato e T2= pós-operatório mediato previamente à morte). Na avaliação da amplitude do movimento de lateralidade direita, nos grupos teste (T45 e T90) houve diferença estatística entre os tempos T0 (33,6 ± 6,3) e T2 (23,0 ± 3,2), bem como entre os tempos T1 (37,2 ± 3,7) e T2 (23,0 ± 3,2), observando-se um p<0,001. Não houve diferença estatística entre os grupos T45, C45, T90 e C90, quanto à amplitude de abertura bucal e lateralidade esquerda nos diferentes deltas avaliados (T1-T0 e T2-T0). A variável amplitude de lateralidade direita apresentou diferença estatística no delta (pós-operatório mediato previamente à morte – préoperatório) entre os grupos T45 (-10,60 ± 4,67) e C45 (2,50 ± 2,12), bem como entre T90 (-13,00 ± 3,56) e C45(2,50 ± 2,12). O delta T1-T0 não apresentou diferenças significativas entre os grupos na variável analisada. Não houve diferença significativa na comparação entre a média do peso no período pré-operatório (T0) e a média do peso no período pós-operatório (T2) nos grupos T45, C45 e T90, bem como quando calculado o delta da subtração T2-T0, na comparação intragrupo. Conclusões: A reconstrução da articulação temporomandibular por meio da técnica de artroplastia biconvexa de Puricelli apresenta estabilidade macroscópica e radiográfica, não interfere na manutenção da amplitude dos movimentos de abertura bucal e lateralidade esquerda, reduz a amplitude dos movimentos de lateralidade direita sem interferência na função alimentar, e não interfere na manutenção do peso corpóreo nos períodos pós-operatórios avaliados.Introduction: The diseases that affect the temporomandibular joint (TMJ) are a heterogeneous group and are generically known as temporomandibular disorders (TMD). In cases of proliferative or ablative articular diseases, there is indication for surgical treatment. The techniques for reconstruction of the temporomandibular joint are indicated when there is partial or complete destruction of articular tissues. The Puricelli’s biconvenx arthroplasty technique proposes the reconstruction of the TMJ through the installation of two convex surfaces of polymethylmethacrylate manipulated during surgery. One of the surfaces is located in the posterior face and above the mandibular fossa and the other in the mandibular segment, being the two convex surfaces in contact with each other at one point. The technique proposed by Puricelli in 1995 has been applied in patients since the year 1978, with clinical success in the operated cases. Objectives: The authors intent to evaluate the technique by the point of view of their imaging control features, performance, and the effect of its implementation on body weight, through its application in animal model. The maximum amplitude of the movements of mouth opening and lateral jaw bilaterally were measured and compared between different periods and study groups. The macroscopic stability and imaging of the convex surfaces of polymethylmethacrylate reconstructed TMJ was evaluated at different postoperative periods. The evaluation of the animals' body weight was performed by comparing the preoperative measure and in different postoperative periods. Methodology: We conducted an experimental study in animal model, controlled, partially blinded. The Puricelli’s biconvenx arthroplasty technique was performed in the left TMJ of the sheep. The control group consisted of four animals, two for each study period. The test group, which underwent the technique consisted of ten animals, five for each study period. The project used fourteen animals. Analyses of reconstruction stability, articular functionality, and body weight were conducted in two days postoperatively, 45 and 90 days. Results: In all test animals, TMJ reconstruction was stable in macroscopic and radiographic postoperative periods evaluated. In the test (T45 and T90) and control groups (C45) was not observed statistical difference in the extent of mouth opening and maximum left lateral movement when compared in the three evaluated times (T0 = preoperative, T1 = immediate postoperative period and T2 = mediate post-surgery prior to death). In assessing the extent of the right lateral movement in the test group (T45 and T90) there was statistical difference betweenT0 (33.6 ± 6.3) and T2 (23.0 ± 3.2), and between T1 (37.2 ± 3.7) and T2 (23.0 ± 3.2), observing a p <0.001. There was no statistical difference between groups T45, C45, C90 and T90, as to the extent of mouth opening and left laterality assessed in different deltas (T1-T0 and T0-T2). The variable amplitude of right lateral presented a statistical difference in the delta (postoperative mediate prior to death - preoperative) between the T45 (-10.60 ± 4.67) and C45 and between T90 (-13.00 ± 3.56) and C45 (2.50 ± 2.12). The delta (T1-T0) showed no significant differences between groups on the analyzed variable. There was no significant difference between the average weight in the preoperative period (T0) and average weight in the postoperative period (T2) in groups T45, T90 and C45, as well as when calculated the variation of the delta T2-T0 in intragroup comparison. Conclusions: The temporomandibular joint reconstruction by using the Puricelli`s biconvex arthroplasty technique has macroscopic and radiographic stability, does not interfere with maintenance of range of motion to open the mouth and left lateral movement, reduces the amplitude of the right lateral movements without interfering with the feeding function and not interfere with the maintenance of body weight in the postoperative periods evaluated, when performed in the left TMJ of the sheep.
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Contador, Carmen Gragera. "Perioperatório nas artroscopias equinas." Bachelor's thesis, Escola Superior Agrária de Elvas - Instituto Politécnico de Portalegre, 2022. http://hdl.handle.net/10400.26/39919.
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O presente trabalho é um relatório de estágio resultado de um período de 3 meses de
estágio na clínica equina BJCM-Vet, entre Outubro de 2021 e Janeiro de 2022. O estágio
teve como principais áreas a medicina interna, odontologia, medicina desportiva e
ortopedia e cirugias (nomeadamente orquiectomias e artroscopias). A estagiária esteve
envolvida na preparação do material e instrumentos e realização de radiofrequências,
stock da clínica, profilaxia e resenhos. Neste sentido foi escolhido como tema principal
as artroscopias, indicadas na sua maioria para a remoção de fragmentos osteocondrais
nas articulações, ressaltando o papel que tem o Enfermeiro Veterinário durante este
tipo de cirugias. Durante o estágio foram acompanhados um total de 233 animais e
especificamente 41 cirugias, nomeadamente 14 artroscopias, 1 tenoscopia, 25
orquiectomias e 1 cirurgia oftalmológica. A artroscopia é um procedimento
minimamente invasivo que permite abordar a articulação através de uma pequena
incisão. O Enfermeiro Veterinário, como parte da equipa de cirugia, tem um papel crucial
na realização deste procedimento, de forma a reduzir o tempo da cirugia e facilitar o
trabalho aos cirurgiões, nomeadamente na avaliação pré-operatoria; na realização de
exames laboratoriais, anamnese e exame físico; no transoperatório; e no período pósoperatório. Constata-se assim que os cuidados perioperatórios são de elevada
importância para o suceso do procedimento cirúrgico, permitindo uma recuperação
com qualidade.The present report is a professional internship report resulting from a 3 month internship period at the equine clinic BJCM-VET, between October 2021 and January 2022. The internship had as prinicipal areas internal medicine, dentistry, sports medicine and orthopedics, surgeries (namely castrations and artroscopy), as well as the previous preparation of the necessary material and instruments, radiofrequencies, clinic stock, prophylaxis and reviews. In this sense, arthroscopies were chosen as the main topic, mostly indicated for the removal osteochondral fragments in the joints, emphasizing the role that the veterinary nurse has during this type of surgery. A total of 41 surgeries were followed, namely 14 arthroscopies, 1 tenoscopy, 25 orchiectomies and 1 ophtalmologic surgery. Arthroscopy is a minimally invasive procedure that allows addressing a joint through a small incision. The veterinary nurse, as part of the surgery team, has a crucial role in carrying out this procedure, in order to reduce the surgery time and facilitate the surgeons´work, namely in the preoperative evaluation; performing laboratory test, anamnesis and physical examination; intraoperatively; and in the postoperative period. It appears that perioperative care is of high importance for the success of the surgical procedure, allowing a quality recovery.
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Barros, Luciano Pereira de. "Estudo experimental e comparativo entre as técnicas de pino em cavilha com fio fluorcarbono monofilamentar e colocefalectomia para estabilização coxofemoral em cães /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/89093.
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Orientador: Cintia Lúcia ManiscalcoBanca: Paola Castro Moraes
Banca: Gustavo Garkalns de Souza Oliveira
Resumo: No presente trabalho comparou-se, experimentalmente, duas técnicas: a estabilização coxofemoral com pino em cavilha ou "toggle pin" e a colocefalectomia. Foram utilizados 16 cães, machos ou fêmeas, distribuidos em dois grupos: o de Pino (GP) e o Colocefalectomia (GC), os quais foram separados em 4 subgrupos: animais com peso superior e, inferior ou igual a 15 kg. Avaliou-se o tempo de cirurgia, o grau de atrofia muscular, a deambulação e a dor, além de presença ou não de alterações radiograficas da articulação. O tempo cirúrgico, devido a maior complexidade da técnica do pino, foi menor no GC. A técnica do GP foi melhor quanto à recuperação do membro, apresentando menor atrofia muscular
Abstract: On the present assay was compared experimentally between two techniques: hip joint stabilization with toggle pin and hip joint stabilization with head of the femur. Were used 16 dogs, female or male, distributed in 2 groups: the pin group (GP) and head of the femur group (GC), the groups were distributed in 4 subgroups: by weight equal, more or less than 15kg. Evaluating the time of surgery, and the notch of muscle atrophy, wander around the pain and also with the presence or not of alterations on the joint radiograph. The time of surgery is longer in the technique of pin than on the group GC, because the technique of pin had more complexity. So the technical of the group GP was better on the recovery member, which presented less muscle atrophy
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