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The Impact of the Mechanical Dependence of the Components of Total Elbow Replacement on Implant Survivorship
Güttler, Kristián ; Landor, Ivan (advisor) ; Koudela, Karel (referee) ; Džupa, Valér (referee)
Drawing on long-term clinical experience, the dissertation provides an overview of the options for the reconstructive surgery of irreversibly damaged elbow joints and the individual structural directions in the development of total elbow replacements. The clinical study focuses on the comparison of the unconstrained Souter-Strathclyde elbow implant, which has been used at our workplace since 1987, and the semiconstrained Coonrad-Morrey implant, which we started to use in the nineties. The disadvantages of the Souter-Strathclyde implant consist of a relatively complex surgery technique and narrower indication which does not permit larger primary instability of the operated elbow and large bone defects. Due to these reasons in recent years the Coonrad-Morrey total elbow replacement has been the preferred option at our workplace. The main problem as regards the long-term survival of this implant is especially the wear of the polyethylene bushings of the fl oppy hinge. This can be solved through an early replacement of this hinge before substantial abrasive wear develops ultimately leading to the loosening of the whole implant. We have elaborated a methodology that maps the condition of the polyethylene bushings and at the same time examines the integration of the humeral and ulnar component in the...
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The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements
Fulín, Petr ; Pokorný, David (advisor) ; Koudela, Karel (referee) ; Gallo, Jiří (referee)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
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Intra-articular Calcaneal Fractures - Osteosynthesis with Calcaneal Locking Compression Plate - Contribution to Fill Defect in Body of Calcaneus
Zeman, Jaroslav ; Koudela, Karel (advisor) ; Plánka, Ladislav (referee) ; Skála-Rosenbaum, Jiří (referee)
Calcaneal fractures are common injuries that prevent patients from getting on with their normal life for a long time. They are usually caused by axial forces leading to impaction of the talus into the calcaneus. Falls and jumps from heights are the most common causes. These fractures also occur bilaterally. We used open reduction and internal fixation with a calcaneal LCP for the treatment of 98 patients with 114 calcaneal fractures in our department from August 2005 till December 2011. Bilateral fractures of the calcaneus occurred in 16 patients - 2 women and 14 men. On the day of injury plain radiographs of the calcaneus in lateral and axial projection were taken. Computed tomography was performed in all operated patients in sagittal, transversal and coronal planes. On the basis of CT findings the fractures were classified as Sanders types I - IV. Patients with type II and III fractures were indicated for surgical ORIF treatment. The results were evaluated using the Rowe score. The aim of the experimental work was to assess the biomechanical strength of the calcaneus without fracture and to compare it with the strength of the calcaneus after the osteosynthesis with an angular stable plate alone or in combination with filling of the calcaneal defect with injectable self-hardening hydroxyapatite...
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Single-Bundle versus Double-Bundle Technique of the Anatomical Anterior Cruciate Ligament Reconstruction
Zeman, Petr ; Koudela, Karel (advisor) ; Skála-Rosenbaum, Jiří (referee) ; Kalina, Radim (referee)
Purpose of the study: The aim of the study is to present a comparison of two years result of double-bundle versus single-bundle anatomical reconstruction of the anterior cruciate ligament using hamstring tendons and their fixation with bioabsorbable interference screws. Material and methods: A total of 110 patients with an isolated anterior cruciate ligament rupture and the healthy contralateral knee who met the indication criteria for double- bundle anterior cruciate ligament reconstruction were intra-operatively allocated at random to either double-bundle group (DB, n=55) or single-bundle group (SB, n=55). At two years after surgery, 82 patients (DB group, n=43; SB group, n=39), comprising 66 men and 16 women, were evaluated; the average age was 29 years and the injury-to- surgery interval was 81 days. Pre-operative and post-operative subjective criteria involved the subjective IKDC and Lysholm score were evaluated. Objectively, the occurrence of graft failure, range of motion deficit, return to pre-injury sports activity, side-to-side difference in anterior laxity of both knees in 20ř flexion on a GNRB laximeter at an applied pressure of 124 N and 250 N, and pivot shift phenomenon were assessed. Results: No statistically significant difference was found in pre-operative values between the two...
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Establishing optimal indications for distal radius fractures, based on fracture type, and comparison of the outcomes of clinical evaluation with mathematical modeling
Vlček, Martin ; Landor, Ivan (advisor) ; Džupa, Valér (referee) ; Koudela, Karel (referee)
Distal radius fractures are the most common types of break to the arm bones. Conservative treatment in unstable fracture types cannot guarantee healing of the bones in a correct anatomical position. Locking plate osteosynthesis is at present regarded as the method of choice in surgical treatment of all types of distal radius fractures. An issue to be solved concerns the role for intramedullary implants in these indications. The aim of our study was to find the optimal indication for each of the osteosynthesis method currently used in distal radius fractures. We evaluated the one-year results of treatment for distal radius fractures. The group evaluated comprised 49 conservatively treated fractures, 78 fractures treated by angle-stable locking plates with either rigiddirection or multidirectional screws and 35 fractures in which Targon DR intramedullary nails or X-screws were used. Some radiographic parameters were better in the patients treated by intramedullary osteosynthesis, while some of the functional outcomes were better in the fractures treated by plate osteosynthesis although this method was indicated in patients with significantly more complicated fractures. A mathematical model was used to simulate distal radius fractures, type C1 and type C2. The stability of both locking plate and intramedullary...
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Distribution and number of wear debris particles around jouint replacements
Veselý, Filip ; Sosna, Antonín (advisor) ; Zima, Tomáš (referee) ; Koudela, Karel (referee)
Aseptic loosening due to polyethylene wear presents one of the most frequently occurring joint replacement complications requiring a revision surgery. Numerous scientific works and publications deal with the issue of morphology, determination and distribution of wear particles. Few studies, however, determine reliably amounts of particles in individual periprosthetic zones. The objective of this work was to evaluate the correlation between amounts of wear particles and periprosthetic osteolysis findings. Description of distribution of these particles in the surroundings of joint replacement presented further objectives of the work. Wear particles were isolated from granuloma obtained during revisions of total hip replacements. Amounts of wear particles were determined using IRc. These findings were correlated with X-ray examinations and intraoperative findings. Method of progressive enzymatic degradation of tissue was used in order to describe wear particles distribution in polyethylene granuloma and surrounding periprosthetic tissues. Results showed uneven incidence of wear particles in the surroundings of the total joint replacement. The incidence correlated with X-ray examinations and intraoperative findings. Distribution of particles was described as well as new determination methods and further...
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The Impact of the Mechanical Dependence of the Components of Total Elbow Replacement on Implant Survivorship
Güttler, Kristián ; Landor, Ivan (advisor) ; Koudela, Karel (referee) ; Džupa, Valér (referee)
Drawing on long-term clinical experience, the dissertation provides an overview of the options for the reconstructive surgery of irreversibly damaged elbow joints and the individual structural directions in the development of total elbow replacements. The clinical study focuses on the comparison of the unconstrained Souter-Strathclyde elbow implant, which has been used at our workplace since 1987, and the semiconstrained Coonrad-Morrey implant, which we started to use in the nineties. The disadvantages of the Souter-Strathclyde implant consist of a relatively complex surgery technique and narrower indication which does not permit larger primary instability of the operated elbow and large bone defects. Due to these reasons in recent years the Coonrad-Morrey total elbow replacement has been the preferred option at our workplace. The main problem as regards the long-term survival of this implant is especially the wear of the polyethylene bushings of the fl oppy hinge. This can be solved through an early replacement of this hinge before substantial abrasive wear develops ultimately leading to the loosening of the whole implant. We have elaborated a methodology that maps the condition of the polyethylene bushings and at the same time examines the integration of the humeral and ulnar component in the...
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Utilization of local carriers of antibiotics for treatment of infection of locomotive apparatus
Melicherčík, Pavel ; Jahoda, David (advisor) ; Koudela, Karel (referee) ; Džupa, Valér (referee)
Infections of locomotive apparatus presents serious problem in orthopeadic and traumatology for a typical course with recidivisms and often evolution to bacterial resistance. Eradication of bacterial causers of infections of locomotive apparatus not have to be always reliable. One of possibility how to increase therapeutic potential is utilization a local aplication of antibiotics. Aim of dessertation thesis is verify influence of released glycopeptide antibiotic vancomycin from bone grafts in experiment in vitro after previous comparasion of properties in 34 chosen carriers from point of view both material constitution and elution characterization for different antibiotics on the strength of sources from accessible literature. The most widespread used local carrier of antibiotics is bone cement intended firstly to solve infections of alloplasties by two-stroke reimplantation. There is necessary subsequent its extraction compared to newer, biodegradable carriers. The best properties from a view of criteria suitable local carrier of antibiotics in orthopeadic and traumatology have carriers composed from several sort of materials, so-called composites. On the strength of results performed experiment we verified that bone grafts could be a good local carrier of vancomycin. Highest average...
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Periprosthetic osteolysis
Veigl, David ; Vavřík, Pavel (advisor) ; Vencovský, Jiří (referee) ; Koudela, Karel (referee)
Periprosthetic osteolysis remains the leading complication of total hip arthroplasty. It often results in aseptic loosening of the implant with a requirement for a revision surgery. Wear-generated particular debris is the main cause of initiating this destructive process. The most important cellular target for wear debris is a macrophage, which responds to particle challenge by activatig proinflamatory signals, which contribute to increased bone resorption. The activation of the RANKL/RANK/OPG system is considered to be a likely cause of periprosthetic osteolysis leading to implant failure. The aim of this study was to examine the possible correlation between the clinical extent of osteolysis, the number of wear particles and the expression of the osteoclastic mediator RANKL in the tissues around aseptically loosened cemented and non-cemened total hip replacements. Periprosthetic tissues were harvested from 59 patients undergoing revision hip replacement for aseptic loosening. We had observed RANKL-positive cells in 23 of our 59 patients, their presence was noted predominantly in tissues with a loosened cemented endoprosthesis. We have shown that RANKL is present only in the tissues with a large amount of wear debris and predominantly in the cases involving lacunar type of osteolysis. Key words:...
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