Tesis: "Orthopaedics"

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Garfjeld-Roberts, Patrick. "Improving simulation training in orthopaedics". Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:c48dcc24-6850-476f-b143-b02cda4e0429.

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The way surgical trainees acquire technical skills is changing in modern surgical training programmes: simulation is proposed as a key part of those changes. Arthroscopy is a surgical technique that is increasing in both incidence and technical complexity; where simulation is becoming common, but evidence is limited. Real-world performance improvements can be measured following simulation training in other fields, but equivalent measures of intra-operative performance are inadequate. Thus, although surgical simulation is popular and improves simulated performance, there is little objective evidence that it improves intra-operative performance. The original contribution of this thesis is to objectively demonstrate the transfer of simulation training into improved intra-operative technical skills. To achieve this, a systematic literature review investigated the quantitative metrics currently used to measure arthroscopic performance, identifying wireless motion analysis as a potential method to assess performance intra-operatively. Motion analysis is a recognised objective method to measure surgical activity which correlates with surgical experience, so wireless motion analysis was validated against a wired motion analysis method commonly used in simulation but not feasible for intra-operative use. Wireless motion analysis metrics were further validated with a simulated arthroscopy list: this environment allowed deliberate practice of arthroscopic sub-skills with proximate feedback for independent practice. This simulated arthroscopy list with wireless motion analysis was used in two randomised studies: the penultimate study of this thesis investigated the impact of simulated practice on the arthroscopic learning curve and showed that performance improved rapidly with independent practice but was not modified by feedback, while the final study investigated additional simulation practice during early surgical training, and objectively demonstrated that additional simulation training improved intra-operative performance compared to traditional training alone. This thesis is the first to objectively show that simulation affects intra-operative behaviour. It sets the groundwork for further investigations into efficient, cost-effective simulation and the impact of simulation training on patient outcomes.

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Du, Plessis Jean-Pierre. "Orthopaedic implications of physeal arrest following meningococcal septicaemia". Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10387.

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Includes bibliographical references (leaves 45-46).
Thirteen patients seen at Red Cross Children's and Maitland Cottage hospitals have under gone complex treatment for the significant deformities caused by meningococcal septicaemia. These patients underwent 62 surgical procedures between them. These procedures were directed at the treatment of sequelae of growth arrest alone and excluded amputations, contracture releases, skin grafts and flaps. The extent of the surgical problems caused by this disease brought about the realisation that a thorough review of the literature and follow up of these patients was required. This would hopefully be of use in assessing the outcomes of various surgical treatment options employed and in developing guidelines for the future management of physeal arrest in these patients.

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Selvey, David M. "Traumatic posterior fracture-dislocation of the hip joint in adults". Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/26636.

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During the period July 1994 to September 1998 surgery was carried out on seventy-six hips in seventy-five patients that sustained posterior fracture-dislocation of their hip joints. During my training I was personally involved in thirteen of these cases and was the primary surgeon in seven cases. Because of my personal interest in these patients Dr Siboto provided me the records of all seventy-five patients for my scrutiny. While he has carried out the surgery on all but the seven cases which I operated on, the literature review, the correlating of the data and all of the interpretation is my own personal work. At surgery prospective records were kept of the degree of comminution of the fracture, the presence of marginal impacting and the presence of fragments in the joint. Fractures were then classified according to Thompson and Epstein (1951). The surgical time was recorded as well as the nature of the associated acetabular floor fracture when it occurred. Anatomical reconstruction was always attempted including elevation of marginal impaction and bone grafting where appropriate. Fragments were only discarded when too small and unattached to permit their inclusion in the reconstruction. All patients had neurological assessment preoperatively and their Sciatic nerves were explored and the state of the nerve recorded at surgery. The process of formulating this dissertation took place over a two-year period from September of 1997 until June of 1999. As a result, the number of patients examined in relationship to a specific subject is not constant but alters according to the group under scrutiny at that particular point in time. An initial review of sixty cases in September 1997 was carried out and then an additional fifteen patients up until September 1998 were included where relevant. The aim of carrying out this study was to gain a better understanding of this injury so that we could formulate a management protocol for our patients in Groote Schuur Hospital. First of all, I reviewed the literature to discover exactly what has been written about this pathology. In the process I hoped to gain a better understanding of the problem and attempt to define a more concise approach to the injury by consolidating the broad array of articles written on this subject. Then by reviewing our findings in our large series of patients I aimed to discover whether we were encountering similar problems to the surgeons who had preceded us and whether we had made any new discoveries that might positively contribute to the future management of these patients.

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4

Hobbs, Hayden Ronald. "Physeal Bar resection for partial growth plate arrest". Master's thesis, University of Cape Town, 2009. http://hdl.handle.net/11427/2843.

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Magampa, Ramanare. "Surgeon directed transcranial motor evoked potential spinal cord monitoring in spinal deformity surgery: A review of viability, safety and efficacy". Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/32793.

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Aims Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury facilitating early intervention which has a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon directed intra-operative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon directed TcMEP is presented in terms of viability, safety and efficacy. Methods A retrospective review was performed on a single surgeon's prospectively maintained database from 2010 to 2017 where TcMEP monitoring was utilised. The upper limbs were used as the control. A true alert was recorded when there was a 50% or more loss of amplitude of the lower limbs with maintained upper limb signals. Patients with true alerts were identified and their case history analysed. Results Of the 299 cases were reviewed, 279 (93.3%) had acceptable traces throughout and awoke with normal clinical neurological function. No case with normal traces had a post-operative clinical neurological deficit. True alerts occurred in 20 (6.7%) cases. The alert group diagnoses included adolescent idiopathic scoliosis 9 (45%) and congenital scoliosis 6 (30%). The incidence of deterioration based on diagnosis AIS was 9/153 (6%), congenital 6/30 (20%) and TB spine 2/16 (12.5%). Deterioration in congenital is much more common (p=0.02) when compared to AIS. 65% of alerts occurred during rod instrumentation and 15% during decompression of the internal apex in vertebral column resection surgery. 4 (20%) alert cases awoke with clinically detectable neurological compromise Conclusion Surgeon directed TcMEP monitoring has a 100% negative predictive value and allows early identification of physiological cord distress and immediate intervention. In resource constrained environments, surgeon directed TcMEP is a viable and effective method of intra-operative spinal cord monitoring. Clinical relevance • Surgeon directed TcMEP monitoring has a 100% negative predictive value. • In resource constrained environments, surgeon directed TcMEP is viable and effective • Level 3 evidence

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6

Vadivelu, Ramanan. "'Fixclips' : internal fixation system in paediatric orthopaedics". Thesis, University of Warwick, 2008. http://wrap.warwick.ac.uk/2305/.

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Jardenius, Daniel y Emil Johansson. "Fotens plantara tryck med hellånga variserande och valgiserande inläggskilar". Thesis, Jönköping University, Jönköping University, School of Health Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-6591.

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Abstract

Introduction

Wedged shoe insoles are used as a treatment for different problems in order to change the ground reaction force. They can secondary cause different loading patterns under the foot compared to normal. No previous study has, to the author’s knowledge, clinically evaluated the plantar foot pressure with different full-length wedges in normal persons.

Purpose

The purpose was to evaluate the plantar pressure with different degrees of full-length wedges in normal persons.

Method

Twenty persons with normal feet have participated in this single blind study. Wedges were produced clinically in four different shapes, 3° valgus, 0° flat, 3° varus och 6° varus. The test persons were told to walk with the wedges in their comfortable pace in a randomized order. The plantar pressure was measured in the medial and lateral heel as well as in the first and fifth metatarsal head.

Results

The results show significant increased mean pressure for varus wedges compared to flat as well as valgus wedges, in the area of the medial heel and first metatarsal joint. Also, valgus wedges show significant increased mean pressure compared to flat condition in area of the medial heel. There is no correlation between wedge height and mean pressure for any of the wedge conditions.

Conclusion

Treatment with wedges leads secondary to increased mean pressure for varus wedges compared to flat as well as valgus wedges, in medial heel and first metatarsal joint. Furthermore, valgus wedges show increased mean pressure compared to flat condition in medial heel. Patients sensitive to high plantar pressures in these areas should be treated with caution. Further studies are recommended.

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Borg, Tomas. "Pelvic Ring Injuries and Acetabular Fractures : Quality of Life Following Surgical Treatment". Doctoral thesis, Uppsala universitet, Ortopedi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-149168.

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The overall aim was to study outcome following surgery of the injured pelvis with focus on assessment from the patient’s perspective. All adult patients operatively treated for pelvic ring injuries or acetabular fractures at the Department of Orthopaedics, Uppsala University, starting 2003 were prospectively included and followed with quality of life (QoL) instruments for 2 years. The most common trauma mechanism was motor vehicle accident (MVA). Study I included 54 patients with pelvic ring injuries during the three-year period 2003-2005. The two instruments, SF-36 and LiSat-11, were used. In 45 responders lower than normative QoL and life satisfaction prevailed at two years after the injury. Study II included 12 patients with pelvic ring injuries or acetabular fractures sustained following a jump from height in an attempt to commit suicide. At four years all patients were still alive and SCID-interviews performed by a psychiatrist revealed low recurrence of self-destructive behaviour and high QoL in the younger patients. Study III included 136 patients with acetabular fractures where 52 had elementary and 84 associated fracture patterns. Fracture reduction was 0-1 mm in 106 patients and 2 mm or more in 30. QoL was significantly higher in patients with anatomically reduced fractures. Physical SF-36 domains improved with time, albeit QoL was lower than norm. Study IV had the aim to construct a condition-specific outcome instrument for patients with acetabular fractures. Closed and open questions were sent to 127 consecutive acetabular fracture patients at 6, 12 and 24 months following surgery. Responses were validated through factor analysis, scree tests, item reduction and principal component analysis which resulted in a multi-item verbal descriptive scale (VDS) with six condition-specific questions related to “Pain”, “Walking”, “Hip motion”, “Leg numbness”, “Sexual life”, “Operation scar” and a global question concerning impact on daily life activities for acetabular fracture assessment.

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9

Linder, Hugo y Viktor Rosenberg. "Mätning av axelkraft : En studie av en modell och prototyp för mätning av axelkraft vid abduktion". Thesis, KTH, Medicinteknik och hälsosystem, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231325.

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Vid rehabilitering är det viktigt att veta om och när muskler vid det skadade området återfår sin styrka. Gällande axelskador finns det idag ingen etablerad metod för mätning av muskelstyrka. I de metoder som testats är vissa attribut inte önskvärda och därför vill man på Karolinska universitetssjukhuset, Huddinge ta fram en ny, förbättrad metod. I metoden ska man kunna mäta en patients muskelstyrka och se skillnaden mellan mätningar över en tidsperiod. Av intresse är den maximala muskelstyrkan samt muskelstyrkan vid 45° abduktion och flexion. Projektet går ut på att ta fram en prototyp som kan användas enligt metoden och se om prototypen är lämplig. En testgrupp bestående av både friska och axelskadade personer genomförde tester för prototypens noggrannhet hos vinkelmätning, prototypens användbarhet samt lämplig vinkel för maximal muskelkraft i axeln. Resultatet visade att prototypens noggrannhet var inom det godkända intervallet för metoden. Användbarheten var också godkänd då alla testpersoner kunde använda prototypen inom de begränsningar vi satte. Vi såg ingen övergripande trend där maximal muskelkraft i axeln erhölls vid 45° även om det stämde för vissa individer. För vidare arbete och ökad validitet krävs fler studier med större testgrupper.
During rehabilitation, it is important to know if and when the muscles in the injured area have regained their strength. Regarding shoulder injuries, there is currently no established method of measuring muscle strength. In the methods tested, certain attributes are undesirable. Therefore, Karolinska Universitetssjukhuset, Huddinge is looking into developing a new, improved method. In this method, one should be able to measure a patient's muscle strength and study the difference in measurements over time. The maximum muscle strength and the muscle strength at 45 ° of abduction and flexion is of interest. The project is to produce a prototype that can be used according to the new method and see if the prototype is appropriate. A test group consisting of both healthy and shoulder injured patients performed tests regarding the prototype accuracy of angular measurement, prototype usability and appropriate angle for maximum muscle strength in the shoulder. The result showed that the prototype accuracy was within the approved range of the method. Usability was also approved as all test subjects could use the prototype within the limits we set. We did not see an overall trend in which maximum muscle force in the shoulder were obtained at 45 °. For further work and increased validity, further studies with larger test groups is required
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Kälfors, Seth y Patrik Lundman. "Samvetsstress hos ortopedingenjörer i Sverige". Thesis, Jönköping University, Hälsohögskolan, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49648.

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Background Stress and burnout in healthcare is a globally occurring problem that has been given attention in both media and research literature. Stress derives partly from a high workload and emotional exhaustion, but ethical and moral factors can also cause stress of conscience which in worst case can lead to burnout. Objectives There is a lack of studies regarding prosthetists and orthotists experience of stress. By using the validated survey Stress of Conscience Questionnaire (SCQ) the aim is to find out the level of stress in prosthetists and orthotists in Sweden. Method A web-based survey with the SCQ instrument was sent to prosthetists and orthotists in Sweden and the answers was compiled using SPSS. Results 68 people answered the survey. The situations that caused the highest stress of conscience for prosthetists and orthotists was when there was a lack of time to provide the care the patient needed, when there were incompatible demands in ones work and when ones work was so demanding that they did not have the energy to devote to their family as they wanted to. Conclusion The results are similar to results from studies made on other healthcare professions which implicates that stress of conscience is as likely for prosthetists and orthotists. A better understanding for causes of stress for prosthetists and orthotists could trough further studies contribute to a better healthcare-climate for both caregivers and patients. Keywords: conscience, stress, mental illness, prosthetists, orthotists
Bakgrund Stress och utbrändhet inom sjukvården är ett globalt förekommande problem som fått mycket uppmärksamhet inom både medier och forskningsvärlden. Stressen kommer delvis från en hög arbetsbörda och emotionella påfrestningar, men även etiska och moraliska faktorer kan ge upphov till samvetsstress som i värsta fall kan leda till utbrändhet. Syfte Det finns en brist på studier om ortopedingenjörers upplevelse av stress. Genom att använda den validerade enkäten Stress of Conscience Questionnaire (SCQ) är syftet att ta reda på nivån av stress hos legitimerade ortopedingenjörer i Sverige. Metod En webenkät med instrumentet SCQ skickades ut till ortopedingenjörer i Sverige och svaren sammanställdes med SPSS. Resultat 68 personer svarade på enkäten. De situationer som orsakar högst samvetsstress för ortopedingenjörer var då man inte upplevde tillräcklig tid till att ge god vård, då man utsätts för oförenliga krav i sitt arbete och då ens arbete är så krävande att man inte orkar ägna sig åt sina närmaste. Slutsatser Dessa resultat speglar resultat från studier gjorda på andra sjukvårdsyrken vilket skulle kunna betyda att samvetsstress är lika sannolikt inom ortopedingenjörsbranschen. En ökad förståelse för vad som orsakar stress för ortopedingenjörer kan genom vidare studier bidra till ett bättre vårdklimat för både kliniker och patienter. Nyckelord: samvete, stress, psykisk ohälsa, ortopedingenjörer

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Alvand, Abtin. "Improving surgical learning and performance at unicompartmental knee arthroplasty". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:faa3e695-2604-4c98-be88-25d7213c4f22.

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Surgery is a difficult skill to teach and even more difficult to assess. In the context of orthopaedic surgery, the Oxford unicompartmental knee arthroplasty (OUKA) is a commonly performed and technically challenging procedure with a variable and sometimes unsatisfactory revision rate. Thus there is a need to develop methods for optimising performance in this procedure. This thesis aims to use this procedure to explore ways of improving teaching methods and assessment methods, and the use of novel technologies to impact surgical performance. No validated technical skill assessment system currently exists to evaluate surgical performance during OUKA. A consensus-based framework of expert opinion (Delphi methodology) was therefore used to determine the essential technical steps of OUKA to aid development of a technical skill assessment system. A procedure-specific assessment scale named the Oxford Arthroplasty Technical Skill Score (OATSS) was produced. Two clinical studies were conducted to demonstrate the inter-rater reliability and construct validity of OATSS in the real operating theatre. This is the first time that a procedure-specific assessment scale has been developed and validated for a complex orthopaedic procedure. The Delphi methodology was also used to identify important radiographic parameters that could be used to predict clinical outcome following OUKA. Two cohort studies used post-operative radiographs of "failed" and "poorly functioning" OUKA cases (with matched controls) to identify several radiographic parameters that can predict the increased risk of a poor clinical outcome. A virtual reality (VR) based simulator (called ViTAL) was developed to teach the cognitive skills necessary for performing the OUKA procedure. This software-based learning environment was used in a randomised controlled study to assess its training effectiveness. This demonstrated that, when used alongside existing teaching modalities, ViTAL resulted in better acquisition of cognitive skills in novice trainees. A randomised controlled study was subsequently undertaken using anatomic dry-model bones in a surgical skills laboratory to determine the effect of cognitive skills training using the ViTAL simulator on the ability of orthopaedic trainees to perform the OUKA procedure. The previously validated OATSS assessment scale was used to evaluate surgical performance. Results demonstrated that this type of training not only improved acquisition of cognitive skills, but also resulted in better technical skill performance during OUKA procedures. This demonstrates, for the first time, the effectiveness of a purely cognitive VR-based simulator for improving technical skills during arthroplasty surgery. Patient-specific instrumentation (PSI) is a novel and exciting technological development within orthopaedic surgery. A prospective RCT was performed to compare OUKAs implanted using PSI with those implanted using conventional instrumentation. Intra-operative measurements, together with post-operative radiographic analyses, were performed to determine the accuracy of component positioning. With regards to positioning of the femoral component, there was no difference between the accuracy of PSI and conventional instrumentation. However, accuracy of PSI was poor with regards to positioning of the tibial component. Further improvement to the PSI is needed before this can be recommended for routine use. In conclusion, this thesis has demonstrated that improvement of learning and assessment methods is currently the safest and most feasible means of optimising surgical performance during the OUKA procedure. Although it is important to embrace novel training modalities and technological developments in an attempt to enhance surgical performance, they must be scientifically evaluated to ensure that they deliver real clinical improvements.

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sofi, karlsson y Thorkatla Dagny Thorarinsdottir. "Development and preliminary validation of a new brace appearance questionnaire : A new instrument to investigate, if idiopathic scoliosis patient’s perception of appearance of their Boston corset would influence their compliance and whether it is in a positive or negative way. (A mixed method study)". Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ. Ortopedteknisk plattform, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-45290.

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Aim: To preliminary validate a questionnaire that was developed in this study. The questionnaire was designed to investigate, if patient’s perception of appearance of their Boston corset influences their compliance, in a positive or negative way. Background: Going through brace treatment brings a lot of feelings for adolescent idiopathic scoliosis patients. Not having a “perfect body” decreases body image and self-esteem. It is highly likely that by changing the patients’ perspective of their brace into liking the appearance of it; the probability of positive compliance will increase in patients. Method: Mixed method approach was used to develop and validate a new questionnaire. The development and validation were done using literature, expert and patient groups. Qualitative data was evaluated, and quantitative data was analyzed using Pearson’s correlation coefficient and Cronbach alpha. Result: Preliminary validated questionnaire was created. The group used for validation were all idiopathic scoliosis patients, four boys and four girls, between the age of 6 and 15 years old. Conclusion and outlook: Further validation of the questionnaire is required before applying on future studies. Preliminary results indicate that patients who like the way they appear in their brace are also compliant.
Syfte: Att preliminär validera ett frågeformulär som utvecklades i denna studie. Frågeformuläret var utformat för att undersöka om patientens uppfattning om deras Boston korsett påverkar deras compliance på ett positivt eller negativt sätt. Bakgrund: Att genomgå korsettbehandling innebär många känslor för ungdomar med idiopatisk skolios. Att inte ha en "perfekt kropp" minskar kroppsbilden och självkänslan. Det är högst sannolikt att genom att förändra patienternas perspektiv på deras korsett till att tycka om utseendet på den; så ökar sannolikheten för compliance med positiva känslor. Metod: Mixed Metod användes för att utveckla och validera ett nytt frågeformulär. Utvecklingen och validering gjordes med hjälp av litteratur, expert- och patientgrupper. Kvalitativa data utvärderades och kvantitativa data analyserades med användning av Pearsons korrelationskoefficient och Cronbach alpha. Resultat: Ett preliminärt validerat frågeformulär skapades. Gruppen som användes för validering var idiopatiska skoliospatienter, fyra pojkar och fyra tjejer, mellan 6 och 15 år gamla. Slutsats: Ytterligare validering av frågeformuläret krävs före användning i framtida studier. Preliminära resultat indikerar att patienter som tycker om hur de ser ut i deras korsett också följer compliance med positiva känslor

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Busse, Patricia, Corina Vater, Maik Stiehler, Jörg Nowotny, Philip Kasten, Henriette Bretschneider, Stuart B. Goodman, Michael Gelinsky y Stefan Zwingenberger. "Cytotoxicity of drugs injected into joints in orthopaedics". British Editorial Soc. of Bone & Joint Surgery, 2019. https://tud.qucosa.de/id/qucosa%3A33832.

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Objectives Intra-articular injections of local anaesthetics (LA), glucocorticoids (GC), or hyaluronic acid (HA) are used to treat osteoarthritis (OA). Contrast agents (CA) are needed to prove successful intra-articular injection or aspiration, or to visualize articular structures dynamically during fluoroscopy. Tranexamic acid (TA) is used to control haemostasis and prevent excessive intra-articular bleeding. Despite their common usage, little is known about the cytotoxicity of common drugs injected into joints. Thus, the aim of our study was to investigate the effects of LA, GC, HA, CA, and TA on the viability of primary human chondrocytes and tenocytes in vitro. Methods Human chondrocytes and tenocytes were cultured in a medium with three different drug dilutions (1:2; 1:10; 1:100). The following drugs were used to investigate cytotoxicity: lidocaine hydrochloride 1%; bupivacaine 0.5%; triamcinolone acetonide; dexamethasone 21-palmitate; TA; iodine contrast media; HA; and distilled water. Normal saline served as a control. After an incubation period of 24 hours, cell numbers and morphology were assessed. Results Using LA or GC, especially triamcinolone acetonide, a dilution of 1:100 resulted in only a moderate reduction of viability, while a dilution of 1:10 showed significantly fewer cell counts. TA and CA reduced viability significantly at a dilution of 1:2. Higher dilutions did not affect viability. Notably, HA showed no effects of cytotoxicity in all drug dilutions. Conclusion The toxicity of common intra-articular injectable drugs, assessed by cell viability, is mainly dependent on the dilution of the drug being tested. LA are particularly toxic, whereas HA did not affect cell viability.

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Modena, Enrico <1981&gt. "Spectroscopic study of Bioceramics for Endodontic and Orthopaedics". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4860/1/modena_enrico_tesi.pdf.

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This thesis was aimed at investigating the physical-chemical properties and the behaviour in physiological environment of two classes of bioceramics: calcium silicate-based dental cements and alumina-based femoral heads for hip joint prostheses. The material characterization was performed using spectroscopic techniques such as that allow to obtain information on the molecular structure of the species and phases present in the analyzed samples. Raman, infrared and fluorescence spectroscopy was principally used. Calcium silicate cements, such as MTA (Mineral Trioxide Aggregate), are hydraulic materials that can set in presence of water: this characteristic makes them suitable for oral surgery and in particular as root-end filling materials. With the aim to improve the properties of commercial MTA cements, several MTA-based experimental formulations have been tested with regard to bioactivity (i.e. apatite forming ability) upon ageing in simulated body fluids. The formation of a bone-like apatite layer may support the integration in bone tissue and represents an essential requirement for osteoconduction and osteoinduction. The spectroscopic studies demonstrated that the experimental materials under study had a good bioactivity and were able to remineralize demineralized dentin. . Bioceramics thanks to their excellent mechanical properties and chemical resistance, are widely used as alternative to polymer (UHMWPE) and metal alloys (Cr-Co) for hip-joint prostesis. In order to investigate the in vivo wear mechanisms of three different generations of commercial bioceramics femoral heads (Biolox®, Biolox® forte, and Biolox® delta), fluorescence and Raman spectroscopy were used to investigate the surface properties and residual stresses of retrieved implants. Spectroscopic results suggested different wear mechanisms in the three sets of retrievals. Since Biolox® delta is a relatively recent material, the Raman results on its retrievals has been reported for the first time allowing to validate the in vitro ageing protocols proposed in the literature to simulate the effects of the in vivo wear.

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Modena, Enrico <1981&gt. "Spectroscopic study of Bioceramics for Endodontic and Orthopaedics". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4860/.

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This thesis was aimed at investigating the physical-chemical properties and the behaviour in physiological environment of two classes of bioceramics: calcium silicate-based dental cements and alumina-based femoral heads for hip joint prostheses. The material characterization was performed using spectroscopic techniques such as that allow to obtain information on the molecular structure of the species and phases present in the analyzed samples. Raman, infrared and fluorescence spectroscopy was principally used. Calcium silicate cements, such as MTA (Mineral Trioxide Aggregate), are hydraulic materials that can set in presence of water: this characteristic makes them suitable for oral surgery and in particular as root-end filling materials. With the aim to improve the properties of commercial MTA cements, several MTA-based experimental formulations have been tested with regard to bioactivity (i.e. apatite forming ability) upon ageing in simulated body fluids. The formation of a bone-like apatite layer may support the integration in bone tissue and represents an essential requirement for osteoconduction and osteoinduction. The spectroscopic studies demonstrated that the experimental materials under study had a good bioactivity and were able to remineralize demineralized dentin. . Bioceramics thanks to their excellent mechanical properties and chemical resistance, are widely used as alternative to polymer (UHMWPE) and metal alloys (Cr-Co) for hip-joint prostesis. In order to investigate the in vivo wear mechanisms of three different generations of commercial bioceramics femoral heads (Biolox®, Biolox® forte, and Biolox® delta), fluorescence and Raman spectroscopy were used to investigate the surface properties and residual stresses of retrieved implants. Spectroscopic results suggested different wear mechanisms in the three sets of retrievals. Since Biolox® delta is a relatively recent material, the Raman results on its retrievals has been reported for the first time allowing to validate the in vitro ageing protocols proposed in the literature to simulate the effects of the in vivo wear.

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Leung, Kit-ying y 梁潔瑩. "Anti-bacteria plasma-treated metallic surface for orthopaedics use". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41633994.

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Leung, Kit-ying. "Anti-bacteria plasma-treated metallic surface for orthopaedics use". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41633994.

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18

Kerr, Kathleen Margaret. "An investigation into the sit-stand-sit activity in normal subjects with total hip replacement". Thesis, Queen's University Belfast, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282227.

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Arnell, M. M. "Numerical descriptors of the intersegmental kinematics of gait". Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233041.

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20

Scammell, Brigitte Elfriede. "A study of sympathectomy and fracture repair". Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307327.

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21

Pringle, Wendy Suzanne. "Chorioallantoic membrane culture : its potential for toxicity assessment and its limitations for skeletal tissue culture". Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328538.

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22

George, Grammatopoulos. "Pseudotumours following hip resurfacing : minimising the clinical impact". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:04320e17-2cbc-40b1-b3a8-7b121daa8ecd.

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Metal-on-metal hip resurfacing arthroplasty (MoMHRA) is an alternative treatment option to total hip arthroplasty (THA), especially in the young and active. Despite the early successful results, reports of adverse soft-tissue reactions around the MoMHRA have caused increased concern. These reactions have been termed pseudotumours and have been shown to be associated with increased wear. However, their incidence and aetiology is not known. The broad aims of this thesis were to 1) determine the clinical impact of pseudotumour; and 2) identify ways of reducing the risk of pseudotumour. The clinical impact was determined by examining the incidence and prevalence of pseudotumours needing revision and the subsequent outcome following revision. At the Nuffield Orthopaedic Centre, the 10-year survival of the BHR, commonest MoMHRA used, was 87.1% (95%CI: 83.0% to 91.2%) and the 10-year incidence of revisions due to pseudotumour was 7.5% (95%CI: 4.3% to 10.7%). In a prevalence study of two tertiary referral centres, pseudotumour was identified as the most common revision indication. An outcome based, case-control study characterised outcome following revision due to pseudotumour as inferior to that following revision for any other failure mode, and inferior to the outcome of matched primary THAs. The inferior outcome was associated with the extensive tissue damage at revision. Risk factors contributing to development of pseudotumour were found to be both patient and surgeon related. Patient factors significantly increasing risk included female gender and small component size. Case control studies demonstrated two surgical factors that were associated with significantly increased risk; cup malorientation and a reduction in head neck ratio (HNR) at operation particularly in females. Furthermore, evidence based recommendations were provided on optimum cup orientation and screening practice. Surgeons should aim for a radiographic cup inclination/anteversion zone of 45°/20° ± 10°. Patients with mal-positioned cups, those with high HNR prior to surgery, and those that had significant HNR reduction with the MoMHRA should be considered at increased risk of developing a pseudotumour. An ex vivo study demonstrated that the majority of pseudotumours occur due to high prosthesis wear, and result from an exaggerated innate response with an accompanying variable immune response. However a small but significant number of pseudotumours (20%) were observed with low wear and a prominent immune response. Furthermore, the cups oriented within the optimum zone were associated with less wear. Hence, subsequent in vivo research focused on providing evidence-based guidance on how to achieve the target cup orientation and factors to consider in minimising the scatter in cup orientation observed following hip arthroplasty. This great scatter was mostly due to two factors: 1) the variability between surgeons at orientating a component at implantation and 2) the difference in the pelvic position between implantation and radiographic assessment. The angular offset was 5° for inclination and 8° for anteversion because of the different definitions at impaction and X-Ray. Surgeons should need to be aware of these factors. Greater amount of pelvic movement occurs during MoMHRA, in comparison to THA. To achieve the target MoMHRA cup orientation surgeons should implant the cup with an intra-operative inclination/anteversion of 40°/30°. It is concluded that pseudotumour following MoMHRA has a significant clinical impact. In order to minimise it, surgeons should appropriately select patients and optimise surgical technique to achieve optimum cup orientation and try to avoid reducing the native head neck ratio. Appreciation of risk factors for pseudotumour development (female gender, small size component, cup orientation, HNR reduction), would aid detection prior to extensive soft-tissue damage and improve inferior outcome associated with revision.

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23

Gray, Andrew Colin. "Damage control orthopaedics and the cognitive effects of cerebral fat embolus". Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/24640.

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This thesis consists of two clinical projects and a large animal (ovine) model of severe musculoskeletal trauma under terminal anaesthesia. It involved the analysis of haemodynamic, pulmonary embolic, coagulative and inflammatory response to bilateral femoral fractures and hypovolaemic shock comparing two different surgical strategies of fracture fixation (damage control versus early total care). This study aimed to better quantify the relative consequences of initial surgical management (external fixation versus intramedullary stabilisation) against a background of relative severe injury. Both clinical projects involved the use of Transcranial Doppler ultrasound monitoring of the cerebral circulation to quantify the cerebral embolic load, with detailed clinical cognitive testing and the measurement of a serum marker (S100B protein) of neuronal injury. One study involved trauma patients requiring intramedullary stabilisation of femoral and tibial diaphyseal fractures and the other examined patients undergoing primary lower limb arthroplasty. The primary aim of both studies was to accurately quantify cognitive change following surgery and to assess whether these measurements correlated with intraoperative cerebral embolic load and serum S100B protein concentrations following surgery. The animal study demonstrated a higher pulmonary embolic load with early intramedullary femoral fracture fixation compared to external fixation. However the initial fracture fixation method did not affect animal mortality or changes seen in the measured coagulation and inflammatory markers. Specific and quantifiable defects in cognitive function occurred following surgery in both clinical studies. However, no direct correlation was found between cognitive change and cerebral emboli detection. Altering surgical technique can reduce the embolic load. However a linear correlation between embolic load and clinical outcome was not established.

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24

Segar, Anand Hari. "The effect of obesity upon the lumbar spine". Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:0db5f091-0f6f-4686-957e-22c5390232b0.

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Back pain is a massive global public health problem with multiple contributing factors including obesity. Obesity is thought to be linked to back pain through mechanical factors. However, obesity also causes a systemic low-grade inflammatory milieu. This would suggest a possible biochemical link between obesity, intervertebral disc degeneration, and back pain. Furthermore, the relationship between obesity and the clinical presentation of spine patients is unclear. This thesis aims to examine the effect of and relationship between obesity, the intervertebral discs, and back pain from biochemical, clinical, and epidemiological perspectives. In this thesis, an in vitro study assessed the effect of leptin, a fat-specific cytokine, upon the intervertebral disc. The bovine intervertebral disc was used as a model in a cell culture system. An ex vivo study examined leptin and pro-inflammatory cytokines produced by paraspinal adipose tissue taken during routine surgical procedures from spinal patients. Plasma taken from patients presenting with low back pain was analysed by mass spectrometry and multiplex immunoassay to identify possible protein biomarkers. At an epidemiological level, statistical modelling of the Genodisc patient population was conducted. This was a pan-European study of 2636 patients presenting to tertiary spinal units. Analyses were performed to examine relationships between obesity, quantified by body mass index (BMI), and pain, clinical diagnosis, and spinal degeneration identified on magnetic resonance imaging (MRI). Leptin was shown to increase the production of and expression of degradative and pain-generating molecules by disc cells. A pro-inflammatory environment, especially IL-6, potentiated this response. Leptin and pro-inflammatory cytokines produced by paraspinal fat were unrelated to clinical symptoms. However, levels of the pro-inflammatory cytokines, TNF-α and IL-6, were raised in the plasma of patients with greater pain or those with spinal stenosis. Furthermore, clusterin and complement were identified, by mass spectrometry, as potential biomarkers for spine patients. Epidemiological analyses revealed that obesity was associated with greater back pain, although the magnitude of this association was small. Similarly, obesity was associated with a diagnosis of spinal stenosis. Finally, increased BMI was found to be an independent predictor of disc degeneration, spinal stenosis, and disc herniation on MRI. In summary, this thesis has furthered the clinical understanding of lumbar spine pathology and back pain. It will provide clinicians with a better framework to assess spine patients. These results show that obesity is associated with lumbar spine degeneration and pain. Leptin could be a factor mediating this relationship. Further studies should concentrate on clarifying the mechanism of action of leptin upon the intervertebral disc and assessing the longitudinal effect of obesity upon the lumbar spine. In this thesis, an in vitro study assessed the effect of leptin, a fat-specific cytokine, upon the intervertebral disc. The bovine intervertebral disc was used as a model in a cell culture system. An ex vivo study examined leptin and pro-inflammatory cytokines produced by paraspinal adipose tissue taken during routine surgical procedures from spinal patients. Plasma taken from patients presenting with low back pain was analysed by mass spectrometry and multiplex immunoassay to identify possible protein biomarkers. At an epidemiological level, statistical modelling of the Genodisc patient population was conducted. This was a pan-European study of 2636 patients presenting to tertiary spinal units. Analyses were performed to examine relationships between obesity, quantified by body mass index (BMI), and pain, clinical diagnosis, and spinal degeneration identified on magnetic resonance imaging (MRI). Leptin was shown to increase the production of and expression of degradative and pain-generating molecules by disc cells. A pro-inflammatory environment, especially IL-6, potentiated this response. Leptin and pro-inflammatory cytokines produced by paraspinal fat were unrelated to clinical symptoms. However, levels of the pro-inflammatory cytokines, TNF-α and IL-6, were raised in the plasma of patients with greater pain or those with spinal stenosis. Furthermore, clusterin and complement were identified, by mass spectrometry, as potential biomarkers for spine patients. Epidemiological analyses revealed that obesity was associated with greater back pain, although the magnitude of this association was small. Similarly, obesity was associated with a diagnosis of spinal stenosis. Finally, increased BMI was found to be an independent predictor of disc degeneration, spinal stenosis, and disc herniation on MRI. In summary, this thesis has furthered the clinical understanding of lumbar spine pathology and back pain. It will provide clinicians with a better framework to assess spine patients. These results show that obesity is associated with lumbar spine degeneration and pain. Leptin could be a factor mediating this relationship. Further studies should concentrate on clarifying the mechanism of action of leptin upon the intervertebral disc and assessing the longitudinal effect of obesity upon the lumbar spine.

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25

Minde, Jan. "Norrbottnian congenital insensitivity to pain". Doctoral thesis, Umeå universitet, Kirurgisk och perioperativ vetenskap, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-746.

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Congenital insensitivity to pain is a rare hereditary neuropathy. We present patients from a large family in Norrbotten, Sweden with a mutation in the nerve growth factor β gene (NGFß). Using a model of recessive inheritance, we identified an 8.3-Mb region on chromosome 1p11.2-p13.2 shared by the affected individuals in the family. Analysis of candidate genes in the disease-critical region revealed a mutation in the coding region of the NGFß gene specific for the disease haplotype. All three severely affected individuals were homozygous for the mutation. The disease haplotype was also observed in both unaffected and mildly affected family members, but in heterozygote form. We have identified 43 patients, 3 homozygous and 40 heterozygous. The homozygous patients have a severe congenital form with onset of symptoms at an early age, most often affecting the lower extremities with insidious progressive joint swellings or painless fractures. Fracture healing was normal, but the arthropathy was progressive, resulting in disabling Charcot joints with gross deformity and instability. These patients lacked deep pain perception in bones and joints and had no protective reflexes, leading to gross bone and joint complications. They also had abnormal temperature perception but normal ability to sweat. There was no mental retardation. Clinically, they fit best into the group HSAN type V. Sural nerve biopsies showed a moderate loss of thin myelinated fibers (Ad-fibers) and a severe reduction of unmyelinated fibers (C-fibers). 14 of the 40 heterozygous adult patients had mild or moderate problems with joint deformities, usually with only slight discomfort. Treatment was conservative with (if needed) different kinds of orthosis and in some cases joint replacement. Three patients had only neuropathy, and 16 patients had no symptoms. In congenital disorders like these, it is important to evaluate the age and also the slowly progressive nature, when considering treatment. There is an increased risk of growth disturbances in the very young. The orthopedic operations should therefore be planned from a long-term point of view, but patient education and orthosis are cornerstones in the treatment—to delay the development of neuropathic arthropathy. Arthrodesis, limb lengthening and spinal decompression with fusions are the only elective procedures that seem reasonable. This Norrbottnian disease is also interesting as a model system for the study of pain.

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26

Molloy, Timothy John St George Clinical School UNSW. "Gene expression in healing tendon". Awarded by:University of New South Wales. St George Clinical School, 2006. http://handle.unsw.edu.au/1959.4/23939.

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Tendon injury is painful and often debilitating, and is a one of the most prevalent soft tissue injuries encountered in the clinic. While common, the underlying molecular and genetic processes of tendon damage and repair remain poorly understood. The work described herein used genome-wide expression analyses to investigate tendon injury and healing from three perspectives. The first identified novel gene expression in tendon fibroblasts following their stimulation with nitric oxide (NO). Of particular relevance to tendon healing was the observation that stimulated fibroblasts express a number of extracellular matrix (ECM) genes in response to NO in a dose-dependent manner, and that NO significantly affects cellular adhesion, a critical process during tendon repair. These findings will be of use when optimising dosages of NO delivery in future work investigating NO as potential treatment for tendon injuries. The second study examined gene expression in an acute tendon injury model in the rat at 1, 7, and 21 days post injury, roughly representing the inflammation, proliferation, and remodelling phase of wound repair. Several novel genes and pathways were found to be differentially expressed at each stage of healing. Of particular interest were the presence of a significant number of genes related to glutamate signaling, a method of cellular communication that has not previously been shown to exist in tendon. Also upregulated were a number of genes which have previously only been associated with embryonic development. Finally, gene expression in a supraspinatus tendinopathy model in the rat was investigated. Several genetic pathways were identified in tendinopathic tendons which have not previously been associated with the disease, and, analogous to the acute injury model study, glutamate signaling gene overexpression was also prevalent. Further in vitro studies showed that the expression of these genes in tendon fibroblasts were stimulated by glutamate treatment, which in turn upregulated pro-apoptotic pathways causing cell death. This may prove to be an important causative factor in the tendon degeneration seen in tendinopathy, in which apoptosis has been identified as playing a significant role. The results of these studies contribute to a better understanding of the aetiology of several extremely common pathologies of this soft tissue, and may help to develop more targeted therapies for increasing the efficacy of tendon healing in future.

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27

Donell, Simon Thomas. "Mechanical factors in the management of osteoarthritis of the knee". Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368174.

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28

Eames, Michael H. A. "'Walking the tightrope' : the excursion of the centre of mass in children with spina bifida". Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322646.

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29

Salkinder, Rael, Toit J. Du y R. P. Lamberts. "Submuscular bridge plating of length-unstable paediatric femoral shaft fractures in children between the ages of 6 and 13". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/97179.

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30

Monk, Andrew Paul. "The patellofemoral joint : form and function". Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:96ce09f2-a72c-46ed-94fd-ed10213959fd.

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The patellofemoral joint (PFJ) is a common source of problems in Orthopaedics and is the source of poorly defined pain and poor function in both normal and replaced knees. Before problems of the PFJ can be fully comprehended a better understanding of the basic form and function of the PFJ is required. The aim of this thesis therefore is to investigate the shape and kinematics of the PFJ and their inter-relations in both normal and replaced knees. The first part of this thesis was concerned with the shape (or form) of the PFJ. Species from the human ancestry over the previous 400 million years were assembled and measurements taken from three dimensional, CT reconstructions, allowing the descriptions of evolutionary changes in the shape, and orientation of the patellofemoral joint in relation to the tibiofemoral compartments. The study chronicled the dramatic changes that occurred in relation to the adoption of the erect bipedal hominin stance which has resulted in varied anatomy at the PFJ, predisposing it to a wide range of pathologies. The articular surface geometry of normal human patellofemoral joints (bone and cartilage) were compared with those of total knee replacements, and patellofemoral joint replacements. Mapping of the trajectory of the apex of the trochlea groove revealed significant differences between native and replaced knees, with the trajectory being orientated laterally in normal knees and either centrally or medially in replaced knees. The second part of this work was concerned with the kinematics (or function) of the PFJ. With current technology it is impossible to measure coronal plane PFJ kinematics with any accuracy in both native and replaced knees. A novel method was developed combining Motion Analysis and UltraSound (MAUS). Validation experiments were undertaken that demonstrated acceptable error (1.8 mm). The MAUS technique was used to show statistically significant differences between the coronal plane kinematics of the patella in normal and replaced knees. In particular in some arthroplasty patients, the patella tracked in the opposite direction to that in normal subjects. The abnormal kinematics were a manifestation of non-anatomical joint replacements. This demonstrates that form and function are closely related. The interaction between form and function in the knee was further investigated using patients with anterior knee pain. Assessment was made of the relationship between patellar subluxation and multiple bony, cartilaginous and soft-tissue factors potentially predisposing to subluxation. The percentage of engagement of the patella in the trochlear groove in knee extension showed the strongest relationship with subluxation, with subjects less than 30% engaged tending to subluxate. This suggests that the most important factor in preventing subluxation is patellar engagement. A clinical study is now required to assess the effect of surgery aimed at improving engagement. The detailed insights into the variability of form and function in the PFJ obtained throughout this thesis will help address pathology in the native knee and guide decisions for new designs of knee replacements. A novel technology has been developed here for measuring patella kinematics which has great potential for future research. The MAUS technique will provide a clinical investigative tool and allow investigation into kinematic abnormalities in other joints.

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31

Cheng, Tegan Laura. "Injectable High Viscosity Liquid Carriers for Bone Tissue Engineering". Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15247.

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The clinical management of critical sized defects and traumatic bone injuries continues to challenge the orthopaedic field. The gold standard of treatment uses autologous bone grafting to promote repair. While effective in many cases, donor site morbidity is a common complication. The field of bone tissue engineering aims to develop viable alternatives to autologous bone graft. The bone graft substitute INFUSE® (bone morphogenetic protein-2 [BMP-2] in acellular collagen sponge) is currently in clinical use, however we and others have hypothesized that the collagen delivery system is suboptimal. This thesis aims to develop high viscosity sugar-based carriers as alternative delivery systems for BMP-2. Initial studies utilise sucrose acetate isobutyrate (SAIB), already in clinical trials for drug delivery. Rodent implantation and fracture models were used to compare SAIB for BMP-2 delivery as well as other adjunctive agents. SAIB/BMP-2 was also trialled in a pig model of hip osteonecrosis. Novel sugar-based carriers were developed using polycondensation and esterification and tested for biocompatibility and in vivo BMP-2 delivery. These studies represent an innovative approach to bone tissue engineering with multiple clinical applications.

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32

Brown, Steven R. "Characterisation of thermal sprayed hydroxyapatite coatings for use as a biological attachment system for prosthetic devices". Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307077.

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33

Kallin, Sara. "Deformation of human soft tissues : Experimental and numerical aspects". Licentiate thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för rehabilitering, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-45653.

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34

Kwong, Kevin Shek Chuen. "Vibration reponse analysis in orthopaedics and its application at the lumbar spine". Thesis, University of Strathclyde, 1995. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21914.

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Vibration response analysis has been carried out on human lumbar spines in-vitro and in-vivo. Random vibration in the frequency range between 20 Hz and 2 kHz was applied to the L5 spinous process in the antero-posterior direction while motion response was measured at the other spinous processes of the lumbar spine. Transfer mobility which defines the lumbar spine's motion response to vibratory force was evaluated by using the fast Fourier transform and spectral averaging technique. There was high damping during the in-vitro tests and the lumbar spine was found to behave as a segmented beam hinged at the thoracic and sacral ends. Fundamental mode shape was observed at frequencies lower than 150 Hz and this pattern was also observed with simulated fusion of the facet joints and interbody fusion. Mobility summated for the whole range of frequency could be modelled by an exponential expression. Useful parameters have been identified and they were found to relate to the lumbar spine's vibratory characteristics resulting from structural modifications. Vibration testing performed on normal subjects revealed that a relaxed lumbar spine was highly damped and non-resonant. First flexural vibration mode was observed only under the action of the back extensors. Averaged figures have been established for the coefficients of an exponential expression which fits closely to the summated mobility curve. The mobility and its attenuation coefficients in different frequency bands have been evaluated from twelve normal subjects. Localized attenuation of vibration response and the reduction in mobility were observed on a patient with osteoporotic lumbar spine. Mobility in the low frequencies was reduced while the medium and high band mobility were enhanced in patients with postero-lateral fusion and instrumentation for fixation of the lumbar spine. The attenuation pattern of these patients was consistent, and corresponded to the existence of structural enhancement.

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35

Bonney, Diva Maria Pires-Ferreira. "A case-based learning environment for trauma in orthopaedics : a comparative analysis". Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438181.

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36

Flynn, Sandra Dawn. "Perceptions of care and caring : an orthopaedic perspective". Thesis, University of Chester, 2013. http://hdl.handle.net/10034/314923.

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“Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn life around,” (Leo F Buscaglia 1924-1998). Caring is a universal phenomenon (Leininger, 1988a, 1991) that influences the way we think, feel and act and is the focus of debate worldwide. Studied since the days of Florence Nightingale and reflected in the literature are numerous theoretical opinions in the search for a comprehensive understanding of caring in the health experience of human beings (Newman et al., 1991). This ethnographic thesis has a caring science perspective (caring in orthopaedics) with the aim of acquiring a greater understanding of perceptions of caring in an orthopaedic clinical setting from both patient and health care professional perspectives. There is a wealth of literature relating to caring which attempts to define and interpret its meaning from several theoretical perspectives. In respect of institutional or professional caring, nursing has historically been synonymous with the notion of care and caring, modest research has been attributed to caring amongst other health care professionals in the wider context. The study used a sequential exploratory mixed methods design and was underpinned by Watson’s Theory of Transpersonal Care in order to discover and illuminate the essential caring behaviours valued by both care givers and care recipients. A total of 30 patients and 53 health care professionals consisting of doctors, nurses, physiotherapists and occupational therapists participated in the study through a three stage approach consisting of questionnaires, observation and semi-structured interviews. The findings revealed both similarities and differences between patients and health care professionals relating to the importance of positive caring behaviours revealed during caring interactions. The questionnaires disclosed that patients statistically rated caring behaviours demonstrated by health care professionals lower than the professionals rated themselves. The data analysis from the participant observation and semi-structured interviews established that although all of the caring caratives according to Watson’s Theory of Care were evident in caring interactions they varied as to the number of times they were exhibited by the respected health care professional groups. Overall patient perception of caring focused upon behaviours related to the caring carative ‘assurance of human presence’ whilst health care professionals considered caring behaviours relating to the caring carative ‘respectful deference’ as the most important. This thesis highlights the need of the patient to feel ‘cared for’ and ‘cared about’ and in today’s modern health care system caring should not be monopolised by one profession but instead the caring concept embraced and the caring dais shared by other professions.

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37

Hopper, Timothy Andrew John. "Quantitative MRI and Micro-CT of bone architecture : applications and limitations in orthopaedics". Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16149/1/Timothy_Hopper_Thesis.pdf.

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The aim of this thesis was to investigate some methods for quantitative analysis of bone structure, particularly techniques which might ultimately be applied post-operatively following orthopaedic reconstruction operations. Initially it was decided to explore the efficacy of MRI in quantifying the bone structure at high resolution by comparing high resolution MRI against 'gold standards' such as Scanning Electron Microscopy (SEM) and optical histology. This basic study provided a measure of the distortions in the morphological bone parameters derived from MR images due to susceptibility artefacts and partial volume effects. The study of bone architecture was then extended to a model of advanced renal osteodystrophy in a growing rat. For this study, high-resolution micro computed tomography (microCT) was used and as a result of the high resolution images obtained, three new bone morphological parameters were introduced to characterise the bone structure. The desire to study bone architecture post-operatively in hip replacements led to a preliminary study on ex-vivo sheep acetabulae following total hip replacement, to determine the extent that the bone architecture could be investigated around the acetabulum. The motivation for studying the acetabulum was based on the high occurrence of debonding at the bone / prosthesis interface. This study demonstrated the superior nature of 3D MRI over conventional x-ray radiographs in early quantitation of fibrous membranes located between the host bone and the non-metallic implant and/or the bone cement. The presence of such fibrous membranes is strongly indicative of failure of the prosthesis. When using clinical MRI to image post-operative hip replacement, the image quality is severely affected by the presence of the metallic implant. The head of the prosthesis is shaped like a metal sphere and is located in the acetabular cup. This problem was investigated by performing simulations of MR images in the presence of the field perturbation induced by the presence of a metal sphere, with the effects of slice excitation and frequency encoding incorporated into the simulations. The simulations were compared with experimental data obtained by imaging a phantom comprising a stainless steel ball bearing immersed in agarose gel. The simulations were used to predict the effects of changing imaging parameters that influence artefact size and also to show how current metal artefact reduction techniques such as view angle tilting (VAT) work and to identify their limitations. It was shown that 2D SE and VAT imaging techniques should not be used when metallic prosthesis are present due to extreme slice distortion, whereas 3D MRI provided a method that has no slice distortion, although the effects of using a frequency encoding gradient still remain.

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38

Hopper, Timothy Andrew John. "Quantitative MRI and Micro-CT of Bone Architecture: Applications and Limitations in Orthopaedics". Queensland University of Technology, 2005. http://eprints.qut.edu.au/16149/.

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The aim of this thesis was to investigate some methods for quantitative analysis of bone structure, particularly techniques which might ultimately be applied post-operatively following orthopaedic reconstruction operations. Initially it was decided to explore the efficacy of MRI in quantifying the bone structure at high resolution by comparing high resolution MRI against 'gold standards' such as Scanning Electron Microscopy (SEM) and optical histology. This basic study provided a measure of the distortions in the morphological bone parameters derived from MR images due to susceptibility artefacts and partial volume effects. The study of bone architecture was then extended to a model of advanced renal osteodystrophy in a growing rat. For this study, high-resolution micro computed tomography (microCT) was used and as a result of the high resolution images obtained, three new bone morphological parameters were introduced to characterise the bone structure. The desire to study bone architecture post-operatively in hip replacements led to a preliminary study on ex-vivo sheep acetabulae following total hip replacement, to determine the extent that the bone architecture could be investigated around the acetabulum. The motivation for studying the acetabulum was based on the high occurrence of debonding at the bone / prosthesis interface. This study demonstrated the superior nature of 3D MRI over conventional x-ray radiographs in early quantitation of fibrous membranes located between the host bone and the non-metallic implant and/or the bone cement. The presence of such fibrous membranes is strongly indicative of failure of the prosthesis. When using clinical MRI to image post-operative hip replacement, the image quality is severely affected by the presence of the metallic implant. The head of the prosthesis is shaped like a metal sphere and is located in the acetabular cup. This problem was investigated by performing simulations of MR images in the presence of the field perturbation induced by the presence of a metal sphere, with the effects of slice excitation and frequency encoding incorporated into the simulations. The simulations were compared with experimental data obtained by imaging a phantom comprising a stainless steel ball bearing immersed in agarose gel. The simulations were used to predict the effects of changing imaging parameters that influence artefact size and also to show how current metal artefact reduction techniques such as view angle tilting (VAT) work and to identify their limitations. It was shown that 2D SE and VAT imaging techniques should not be used when metallic prosthesis are present due to extreme slice distortion, whereas 3D MRI provided a method that has no slice distortion, although the effects of using a frequency encoding gradient still remain.

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39

Joyce, Ann C. "Perspectives of Women in Orthopaedic Surgery on Leadership Development". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6521.

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Over the past 50 years, the demographics of medical school graduates in the United States has changed dramatically with the number of women (47%) almost equaling the number of men in 2014 (AAMC, 2014). However, the Association of American Medical Colleges (2014) reports that orthopaedic surgery has the lowest proportion of female residents, instructors, assistants, associate, and full professors of all the sub-specialties and little has changed in the past several decades. Due to the healthcare reform and the changing needs of our society, it is importance to recruit, retain, and promote women into leadership positions. The purpose of this study is to ensure the success of women in orthopaedic surgery. A self-report survey was sent to all known women in orthopaedic surgery. The survey assessed perspectives of women in orthopaedic surgery in regards to organizational culture, leadership development, challenges, diversity, gender bias, recruitment, and retainment. An examination of the data provides insights into areas of improvement and implications for institutional practice. The results indicated that although institutions are making progress, more advocacy for gender equality, pro-family policies, and employee retention is needed.

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40

Mokáň, Dan. "Analýza a strategie firmy Beznoska s.r.o. na domácím a zahraničních trzích". Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-192552.

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The thesis analyses the company Beznoska s.r.o. on the domestic and foreign markets. It describes the activities and strategy of the company, which is engaged in the production of orthopaedic implants and implants in the field of orthopaedics. The second part of the thesis focuses on the analysis of the domestic market, i.e. the Czech Republic. It analyses particularly Ukraine from the foreign markets. Subsequently, by using comparison and analysis among the selected countries, it is searching for potential market for company expansion.

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41

Mushipe, Moses Taurayi. "Use of biomaterial particulates in bone repair". Thesis, Queen Mary, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367909.

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42

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

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

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43

Cook, Juliette Emma. "Fretting wear of total hip replacement femoral stems". Thesis, University of Exeter, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263286.

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44

Watkins, P. E. "A study of mechanical influences on fracture healing, and on fracture non-union". Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376622.

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45

Rout, R. "Molecular and cellular features of anteromedial gonarthrosis". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:29c40452-7641-4884-8ab4-ec2ad7cb4152.

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Anteromedial Gonarthrosis (AMG) is a distinct phenotype of knee osteoarthritis (OA), with a specific pattern of disease on the tibia. There is full thickness cartilage loss anteromedially, progressing to an area of damaged cartilage, and then to an area of macroscopically and histologically normal cartilage posteriorly. This reproducible pattern of disease can be considered to be a spatial model of OA progression and provides an alternative and less biologically varied set of specimens than the commonly used multiple joint compartments in which to quantify disease-related changes. The aim of this thesis was to explore in detail spatial and quantitative differences in cell, matrix and molecular features between areas of cartilage in AMG. A real time PCR study was undertaken comparing damaged and undamaged cartilage in AMG. Previous work from our research group had shown increased type I collagen content of undamaged cartilage in AMG. This gene expression study corroborated this finding by demonstrating increased COL1A1 expression in undamaged cartilage, compared to damaged cartilage. MMP1, MMP3, MMP13 and ADAMTS4 were also shown to have increased expression in undamaged cartilage. Since these changes arise in tissue before any macroscopic damage is apparent, these may indicate early changes of the cartilage matrix in AMG. In order to confirm that these changes are directly related to the damage process and not only to normal regional variations, Above Knee Amputations were collected from patients with peripheral vascular disease but no overt OA and a template of the AMG joint surface created to allow for matched regional sampling. Studies into their histology, immunoassays and qPCR were performed in order to compare results with those from AMG specimens. Histology demonstrated low scores throughout but allowed for a division into lower (macroscopically and histologically normal) and higher grade (surface wear/possible early signs of OA) groups. Immunoassays showed elevated type I collagen in high grade but not low grade groups in the posterior cartilage. No differences in mRNA expression were detected using qPCR suggesting that changes seen in AMG specimens were specific to the OA disease process. Because the causes of cell death in OA are not fully understood an immunohistochemical study into apoptosis was performed. TUNEL staining demonstrated higher levels of apoptosis, the more damaged the cartilage. The presence of Active Caspase 3, Cytochrome C, Active Bax and Bim with the same distributions demonstrated apoptosis occurring via the intrinsic or mitochondrial pathway. The high levels of 3-Nitrotyosine in more damaged cartilage implicated reactive oxygen species in apoptotic mechanisms. A microarray study was conducted comparing regions of damaged and undamaged cartilage in AMG. 389 genes were found to be significantly differentially expressed between regions. Several pathways rich in gene expression changes were highlighted including cellular development, inflammatory response and skeletal disorders. Results suggest complex changes in the signaling microenvironment of AMG and identify areas for future study. In summary, this thesis has highlighted several quantitative molecular and cellular differences between regions of cartilage in AMG, demonstrating its usefulness as a tight disease model. Gene expression differences corroborate changes previously seen by immunohistochemistry; microarray has shown the wider picture of gene expression changes. Apoptosis has been shown to occur via the intrinsic pathway and involve reactive oxygen species, highlighting this damage pathway as an important driver of cell loss. Most importantly this thesis has identified the apparently normal region in AMG specimens as a region undergoing considerable molecular changes and as a potential early disease model. The dysregulation of collagen I distribution seen in AMG and slightly worn AKA specimens is very interesting and suggests a possible early response to loading alterations caused by joint wear and opening the way for future experiments. The identification of wear patterns in AKA specimens specifically mapping to the zone of maximal damage in AMG confirms the site of initial injury and progression over time proposed in this model. These AKA specimens with no overt OA should therefore be used in future studies to assess emerging biomarkers of disease progression.

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46

Kendrick, Benjamin J. L. "Fixation of the Oxford unicompartmental knee replacement". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:0137ea96-ca9a-4f4e-8a37-53602903f28f.

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The Oxford Unicompartmental Knee Replacement (UKR) is a commonly performed procedure, with a good clinical outcome at 15 years, however, radiolucent lines are commonly found beneath the tibial tray. With the projected increase in knee arthroplasty, particularly in younger patients, implant longevity is of paramount importance. The aim of this thesis is to understand how fixation is achieved with the Oxford UKR and how it can be improved. A histological study demonstrated that in the presence of a radiolucent line the tibial bone-cement interface is made up of a combination of direct bony contact, fibrocartilage and fibrous tissue. The radiolucency is more marked when there is more soft tissue. However in all cases there is some direct bony contact. Cemented and cementless fixation was compared in a randomised controlled study using radiostereometric analysis and fluoroscopic imaging of the interfaces. In the first year the cementless tibial component subsided on average 0.28 mm and had an increased posterior slope of 0.40°, whereas the cemented component only subsided 0.09 mm, with a 0.10° increase in slope. In the second year both components had very little further subsidence (mean<0.05 mm) and no increase in posterior slope. In the second year a single cementless tibial component subsided greater than 0.15 mm, whereas four cemented components, all with radiolucencies, subsided more than 0.15 mm. At two years the cemented components had a significantly higher prevalence of radiolucency (62% v 29%), with 24% having a complete radiolucency, whereas no cementless components had a complete radiolucency. Two designs of lateral UKR were also compared. These had a flat tibial component that predominantly transmits compressive loading, and a domed component that also transmits shear. There was a lower prevalence of radiolucency in the domed tibia (13% v 60%), even though there was a similar amount of migration as the cemented medial tibial component. In conclusion radiolucent lines, both partial and complete, are common with cemented components, and may, in part, be a result of compressive loading. They are associated with good long-term results and direct bone cement contact indicating satisfactory fixation. However, they are also associated with increased migration and soft tissue at the interface suggesting that the fixation, although satisfactory, is suboptimal. The cementless components had no complete radiolucencies and low levels of migration in the second year. This suggests that bone ingrowth and secure fixation occurs reliably, and therefore that cementless fixation may be better than cemented for the Oxford UKR.

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47

Bottomley, Nicholas J. "Anteromedial osteoarthritis : a surgical perspective of incidence, progression and risk factors". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:34c87265-bbae-4018-b120-ef1d6bed73aa.

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Anteromedial osteoarthritis of the knee (AMOA) has been defined anatomically, histologically and radiologically and yet little is known about the epidemiology of the disease or the risk factors involved in the development of the disease. The broad aim of this thesis was to combine clinical insight with the utilisation of modern, large epidemiological datasets to provide information to inform better the clinical management of patients with AMOA. Specifically, the prevalence and incidence of AMOA, the time taken to progress from early disease to severe disease that may require surgical intervention, the radiological characterisation of disease and the assessment of mechanical risk factors implicit in the development of this pattern of disease are investigated. A cross-sectional study of the radiological prevalence of AMOA in a symptomatic cohort in a specialist secondary care knee clinic showed that AMOA was the commonest pattern of knee OA, present in more than 60% of symptomatic subjects. Less than 25% of subjects with AMOA presented with advanced or 'bone-on-bone' disease, emphasising the clinical importance of understanding the progression from earlier stages of disease to this advanced stage. A 20-year longitudinal radiographic study was performed on 1000 women to describe the prevalence, incidence and progression of AMOA. The prevalence of AMOA was 43% and the incidence over 20-years was 0.4. Life table analysis showed that the risk of developing advanced AMOA in a previously normal knee was 2.6%. Of those subjects with early radiological AMOA, 11% progressed to advanced 'bone-on-bone' disease within 10 years and 37% within 20 years. The role of mechanical risk factors in the development of AMOA showed that both anatomical limb and proximal tibial alignment were significantly more varus aligned in those that developed AMOA at 20-years. Assessment of the shape of the medial tibial plateau in a longitudinal MRI study showed that the angle of the upslope at the anterior aspect of the plateau was significantly increased in the group that subsequently developed AMOA. To enable AMOA to be studies in future MRI studies, the MRI description of the disease was defined. In summary, AMOA was shown to be the most common pattern of knee OA both in symptomatic surgical cohorts and in the community. The progression of the disease from an early stage to an advanced stage, which may require surgical intervention, was described for the first time. To enable better the recognition of AMOA in modern epidemiological studies, the MRI description of AMOA was defined and the clinical relevance of modern MRI was discussed. The anatomical alignment of the limb, the alignment of the proximal tibia and the morphology of the tibial plateau were all shown to have a role in the development of AMOA. Addressing these mechanical factors may provide a therapeutic surgical target for the management of patients with AMOA.

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48

Rumpf, Christian. "New minimally-invasive laser treatment in orthopaedics on spinal deformations and bone tumours". [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=961840242.

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49

Malis, Emma. "The Effect of Mechanical Stimuli on Healing Achilles Tendons in Rats". Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19329.

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Tendon healing is a slow process and the tendon may not regain its initial mechanical properties after rupture. Mechanical stimuli have shown to have positive effect on tendon healing. This study is the first to investigate the effect of vibration stimuli on healing tendons. Vibration was also compared to treadmill running, which has previously been used for mechanical stimuli.63 female Sprauge-Dawley rats were used. A 3 mm segment was removed from the Achilles tendon and the tendon was left to heal. The animals were subjected to 15 min of daily exercise, vibration or treadmill running or acted as controls without exercise. The study was divided into three experiments. Experiment 1; the animals had full time cage activity and was randomized into running, vibration and control group. Experiment 2; the animals were unloaded and randomized into vibration, running and control group. There was also a control group with full time cage activity in experiment 2. Experiment 3; the animals were unloaded and randomized into vibration and placebo group. 14 days after surgery the animals were killed and mechanical testing of the Achilles tendons was performed. The results showed no significant difference between the groups in experiment 1. Experiment 2 showed that controls with full time cage activity had higher peak load, stiffness and cross sectional area than unloaded running, vibration and control groups. In experiment 3, there was no significant difference between vibration and placebo group. In conclusion, this study shows that vibration, as applied here, does not affect tendon healing.

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50

Thompson, Mark S. "The design of a novel hip resurfacing prosthesis". Thesis, Queen Mary, University of London, 2001. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28944.

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Total hip replacement (THR) is one of the most successful and most frequently performed operations. For most implants the published rate of revision at 10 years is less than 10%. However the revision rates are higher for younger and more active patients who are likely to outlive their implants. The most frequent cause of THR failure is aseptic loosening, commonly accompanied by bone loss at the implant site. THR revisions give worse functional results and fail sooner than primary THR and are complicated by this loss of bone stock. A resurfacing hip prosthesis replaces the diseased surface layer of bone and cartilage and retains the majority of the femoral head. The stress distribution in the proximal femur is closer to that in an intact hip. A conservative resurfacing prosthesis will present the surgeon with no greater problems at revision than encountered at primary conventional 11-JR. Early designs of resurfacing prosthesis conserved femoral bone stock at the expense of acetabular bone. Revision rates were high and while some failures were caused by avascular necrosis and femoral neck fracture the predominant cause was acetabular loosening. The design of a bone conserving prosthesis requires knowledge of the shape of the bony surfaces of the hip joint. A survey of the morphology of the acetabulum showed a wide variation in shape. While early resurfacing designs had hemispherical acetabular cups the bony surface is less than hemispherical. The morphology and desired range of hip motion constrain prosthesis thickness and shape. A novel resurfacing design using a polyacetal femoral component and an UHMWPE acetabular component is proposed. This bearing combination has a lower volumetric wear rate than an equivalent Co-Cr on UHWMPE bearing. Computer modelling of the resurfacing concept showed that lower moduli materials reduced stress shielding and distributed implant-bone interface stresses more evenly. Mechanical testing of polyacetal following immersion in Ringer's solution showed substantial decreases in Young's modulus while strength was unaffected.

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