TY - THES A1 - Rehlinghaus, Marc Christoph T1 - Verletzungen im Radsport. Im retro- und prospektiven Studiendesign. T1 - Cycling related injuries: a retro- and prospective study design N2 - Es wurden 398 Teilnehmende (männlich: n=343/86,2%; weiblich: n=54/13,6%) retrospektiv befragt. Aus dieser Befragung resultierten 509 Sturzereignisse mit insgesamt 1721 Einzelverletzungen. Zudem wurden von 96 Teilnehmenden (m=82; w=14) die Verletzungen über zwei Jahre prospektiv analysiert. In dieser Zeit kam es bei 43 Teilnehmenden (44,8%) zu 64 Sturzereignissen mit 201 Einzelverletzungen. Vor allem eigene Fehler, wie fehlende Fahrtechnik oder Überschätzung, wurden mit über 60% als Sturzursache genannt. Von den angegebenen Stürzen ereignete sich jeder Dritte bei Wettkämpfen. Die häufigsten Verletzungsregionen waren der Oberkörper und der Unterkörper. Es dominierten über alle Bereiche hinweg Schürfwunden und Prellungen. Die häufigsten Frakturen waren Clavikulafrakturen sowie Frakturen der Hand. Entsprechend waren bei den 17,49% der Teilnehmenden, bei denen eine operative Versorgung der Verletzung notwendig war, die häufigsten Eingriffe eine Wundversorgung und operativ versorgte Frakturen der Clavicula und der Handknochen. Abdominelle Organverletzungen waren selten (0,79%), führten jedoch zu zwei Splenektomien und einer Nephrektomie. Von den Teilnehmenden gaben 20% an, unter schmerzbedingten oder funktionellen Einschränkungen zu leiden. Diese sind aber meist leicht (13,5%). Der Radsport, gemessen an Verletzungen, die pro 1000 Stunden entstanden sind, zeigt kein erhöhtes Verletzungsrisiko im Vergleich zu anderen Sportarten. Adäquate Schutzausrüstung vermindert das Verletzungsrisiko und wird von den meisten RadsportlerInnen getragen. Durch Techniktraining und das Betreiben unterschiedlicher Radsportarten kann das Risiko einen Sturz zu erleiden, gesenkt werden. Bei den Sportschäden dominierten Beschwerden im Kniegelenk (19,28%) sowie Nacken- (13,62%) und Rückenbeschwerden (15,17%). Eine Verbesserung der Beschwerden oder vollständige Remission der Beschwerden wurde bei 59,22% der Teilnehmenden erreicht. N2 - Cycling has become increasingly popular in recent years. This study aims to investigate the incidence of cycling accidents as well as the overall accident mechanism. The influence of material, rider and environment on the occurrence of an accident will be shown in this study. In this trial 398 participants (male: 86.2% (n= 343), female: 13.6% (n= 54)) were surveyed retrospectively. This survey included 509 incidents with a a total of 1721 individual injuries. In addition was the data of 96 participants (male= 82, female= 14) injuries prospectively analyzed over two years. During this time, 64 incidents occurred to 43 participants (44.8%) with 201 individual injuries. Mainly human mistakes, such as lack of riding technique or overestimation, were in over 60% the cause of the incident. Of the stated incidents, every third occurred during competitions. The most common injury regions were the upper body and the lower body. Scrapes and bruises dominated across all bodyareas. The most common fractures were clavicle fractures and fractures of the hand. In 17.49% of participants surgical treatment of the injury was necessary. The most frequent interventions were wound care and surgically treated fractures of the clavicle and hand bones. Abdominal organ injuries were rare (0.79%) but resulted in two splenectomies and one nephrectomy. 20% of the participants reported suffering from pain-related or functional limitations after acute injuries. However, these were mostly mild injuries (13.5%). Cycling, as measured by injuries incurred per 1000 hours, showed no increased risk of injury compared to other sports. Adequate protective equipment reduces the risk of injury and is worn by most cycling athletes. Through technique training and the practice of different cycling activities, the risk of accidents can be reduced. Among the sports injuries were dominated by complaints in the knee joint (19.28%) and neck (13.62%) and back complaints (15.17%). An improvement of the complaints or complete remission of the complaints was achieved in 59.22% of the participants. Compared to other sports, cycling does not show an increased risk of injury. Recommended preventive measures are, above all, the wearing of protective clothing adapted to the cycling discipline and the completion of technical training. Organizers of cycling races should mark danger spots on routes and inform participants in advance. Women and men should start in separate fields. KW - Sporttraumatologie KW - Radsport KW - Sportverletzungen Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-320473 ER - TY - JOUR A1 - Patzer, Theresa Sophie A1 - Kunz, Andreas Steven A1 - Huflage, Henner A1 - Conrads, Nora A1 - Luetkens, Karsten Sebastian A1 - Pannenbecker, Pauline A1 - Paul, Mila Marie A1 - Ergün, Süleyman A1 - Bley, Thorsten Alexander A1 - Grunz, Jan-Peter T1 - Ultrahigh-resolution photon-counting CT in cadaveric fracture models: spatial frequency is not everything JF - Diagnostics N2 - In this study, the impact of reconstruction sharpness on the visualization of the appendicular skeleton in ultrahigh-resolution (UHR) photon-counting detector (PCD) CT was investigated. Sixteen cadaveric extremities (eight fractured) were examined with a standardized 120 kVp scan protocol (CTDI\(_{vol}\) 10 mGy). Images were reconstructed with the sharpest non-UHR kernel (Br76) and all available UHR kernels (Br80 to Br96). Seven radiologists evaluated image quality and fracture assessability. Interrater agreement was assessed with the intraclass correlation coefficient. For quantitative comparisons, signal-to-noise-ratios (SNRs) were calculated. Subjective image quality was best for Br84 (median 1, interquartile range 1–3; p ≤ 0.003). Regarding fracture assessability, no significant difference was ascertained between Br76, Br80 and Br84 (p > 0.999), with inferior ratings for all sharper kernels (p < 0.001). Interrater agreement for image quality (0.795, 0.732–0.848; p < 0.001) and fracture assessability (0.880; 0.842–0.911; p < 0.001) was good. SNR was highest for Br76 (3.4, 3.0–3.9) with no significant difference to Br80 and Br84 (p > 0.999). Br76 and Br80 produced higher SNRs than all kernels sharper than Br84 (p ≤ 0.026). In conclusion, PCD-CT reconstructions with a moderate UHR kernel offer superior image quality for visualizing the appendicular skeleton. Fracture assessability benefits from sharp non-UHR and moderate UHR kernels, while ultra-sharp reconstructions incur augmented image noise. KW - photon-counting KW - tomography KW - X-ray computed KW - fracture KW - cancellous bone KW - convolution kernel Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-319281 SN - 2075-4418 VL - 13 IS - 10 ER - TY - JOUR A1 - Watzling, Martin A1 - Klaus, Lorenz A1 - Weidemeier, Tamara A1 - Horder, Hannes A1 - Ebert, Regina A1 - Blunk, Torsten A1 - Bauer-Kreisel, Petra T1 - Three-dimensional breast cancer model to investigate CCL5/CCR1 expression mediated by direct contact between breast cancer cells and adipose-derived stromal cells or adipocytes JF - Cancers N2 - The tumor microenvironment (TME) in breast cancer is determined by the complex crosstalk of cancer cells with adipose tissue-inherent cells such as adipose-derived stromal cells (ASCs) and adipocytes resulting from the local invasion of tumor cells in the mammary fat pad. This leads to heterotypic cellular contacts between these cell types. To adequately mimic the specific cell-to-cell interaction in an in vivo-like 3D environment, we developed a direct co-culture spheroid model using ASCs or differentiated adipocytes in combination with MDA-MB-231 or MCF-7 breast carcinoma cells. Co-spheroids were generated in a well-defined and reproducible manner in a high-throughput process. We compared the expression of the tumor-promoting chemokine CCL5 and its cognate receptors in these co-spheroids to indirect and direct standard 2D co-cultures. A marked up-regulation of CCL5 and in particular the receptor CCR1 with strict dependence on cell–cell contacts and culture dimensionality was evident. Furthermore, the impact of direct contacts between ASCs and tumor cells and the involvement of CCR1 in promoting tumor cell migration were demonstrated. Overall, these results show the importance of direct 3D co-culture models to better represent the complex tumor–stroma interaction in a tissue-like context. The unveiling of tumor-specific markers that are up-regulated upon direct cell–cell contact with neighboring stromal cells, as demonstrated in the 3D co-culture spheroids, may represent a promising strategy to find new targets for the diagnosis and treatment of invasive breast cancer. KW - 3D breast cancer model KW - adipose-derived stromal cells KW - adipocytes KW - adipose tissue KW - spheroids KW - co-culture Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-362502 SN - 2072-6694 VL - 15 IS - 13 ER - TY - JOUR A1 - Mrestani, Achmed A1 - Lichter, Katharina A1 - Sirén, Anna-Leena A1 - Heckmann, Manfred A1 - Paul, Mila M. A1 - Pauli, Martin T1 - Single-molecule localization microscopy of presynaptic active zones in Drosophila melanogaster after rapid cryofixation JF - International Journal of Molecular Sciences N2 - Single-molecule localization microscopy (SMLM) greatly advances structural studies of diverse biological tissues. For example, presynaptic active zone (AZ) nanotopology is resolved in increasing detail. Immunofluorescence imaging of AZ proteins usually relies on epitope preservation using aldehyde-based immunocompetent fixation. Cryofixation techniques, such as high-pressure freezing (HPF) and freeze substitution (FS), are widely used for ultrastructural studies of presynaptic architecture in electron microscopy (EM). HPF/FS demonstrated nearer-to-native preservation of AZ ultrastructure, e.g., by facilitating single filamentous structures. Here, we present a protocol combining the advantages of HPF/FS and direct stochastic optical reconstruction microscopy (dSTORM) to quantify nanotopology of the AZ scaffold protein Bruchpilot (Brp) at neuromuscular junctions (NMJs) of Drosophila melanogaster. Using this standardized model, we tested for preservation of Brp clusters in different FS protocols compared to classical aldehyde fixation. In HPF/FS samples, presynaptic boutons were structurally well preserved with ~22% smaller Brp clusters that allowed quantification of subcluster topology. In summary, we established a standardized near-to-native preparation and immunohistochemistry protocol for SMLM analyses of AZ protein clusters in a defined model synapse. Our protocol could be adapted to study protein arrangements at single-molecule resolution in other intact tissue preparations. KW - active zone KW - nanotopology KW - neuromuscular junction KW - high-pressure freezing/freeze substitution KW - PFA in ethanol KW - dSTORM KW - Drosophila melanogaster Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304904 SN - 1422-0067 VL - 24 IS - 3 ER - TY - JOUR A1 - Bernuth, Silvia A1 - Vater, Adrian A1 - Fuchs, Konrad F. A1 - Meffert, Rainer H. A1 - Jakubietz, Rafael G. T1 - Perfusion changes in perforator-based propeller flaps JF - Journal of Reconstructive Microsurgery Open N2 - Background  To cover soft tissue defects, the perforator-based propeller flap offers the option to rotate healthy tissue into complex wounds. By rotating the flap, the perforator is torqued. As a result, perfusion changes are possible. Methods  A retrospective data analysis of patients was done, who received a propeller flap to cover soft tissue defects of the lower extremity as well as a peri- and postoperative perfusion monitoring with a laser-Doppler-spectrophotometry system. Additionally, patient-specific data were collected. Results  Seven patients were identified. Four patients experienced early complications, two epidermolysis of the distal flap areas, three wound healing disorders, and one partial flap necrosis. Intraoperative perfusion monitoring showed a decline of blood flow after incision of the flap, especially at distal flap site. In case of complications, there were prolonged blood flow declines up to the first postoperative day. Conclusion  Torqueing the perforator by rotating the flap can cause an impairment in inflow and outflow. If the impairment is prolonged, perfusion-associated complications are possible. The identification of a viable perforator is particularly important. In addition, a conservative postoperative mobilization is necessary to compensate for the impaired and adapting outflow. KW - propeller flap KW - perfusion KW - lower extremity Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350491 SN - 2377-0813 VL - 8 IS - 1 ER - TY - JOUR A1 - Renner, Tobias A1 - Otto, Paul A1 - Kübler, Alexander C. A1 - Hölscher-Doht, Stefanie A1 - Gbureck, Uwe T1 - Novel adhesive mineral-organic bone cements based on phosphoserine and magnesium phosphates or oxides JF - Journal of Materials Science: Materials in Medicine N2 - Present surgical situations require a bone adhesive which has not yet been developed for use in clinical applications. Recently, phosphoserine modified cements (PMC) based on mixtures of o-phosphoserine (OPLS) and calcium phosphates, such as tetracalcium phosphate (TTCP) or α-tricalcium phosphate (α-TCP) as well as chelate setting magnesium phosphate cements have gained increasing popularity for their use as mineral bone adhesives. Here, we investigated new mineral-organic bone cements based on phosphoserine and magnesium phosphates or oxides, which possess excellent adhesive properties. These were analyzed by X-ray diffraction, Fourier infrared spectroscopy and electron microscopy and subjected to mechanical tests to determine the bond strength to bone after ageing at physiological conditions. The novel biomineral adhesives demonstrate excellent bond strength to bone with approximately 6.6–7.3 MPa under shear load. The adhesives are also promising due to their cohesive failure pattern and ductile character. In this context, the new adhesive cements are superior to currently prevailing bone adhesives. Future efforts on bone adhesives made from phosphoserine and Mg2+ appear to be very worthwhile. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357342 VL - 34 ER - TY - THES A1 - Wetterich, Maximilian Michael T1 - Meniskuschirurgie: Eine Analyse zu aktuellen Behandlungsstrategien, Risikofaktoren, diagnostischen Verfahren und bisherigen ätiologischen Grundlagen T1 - Meniscus Surgery: An Analysis of Current Treatment Strategies, Risk Factors, Diagnostic Methods and Previous Etiological Bases N2 - Die Menisken sind ein vitaler Bestandteil für die Stabilität und Mobilität des Kniegelenks. Verletzungen des Meniskus weisen eine hohe Prävalenz in der Bevölkerung auf. Schätzungsweise sind bis zu 25% der Erwachsenen in den USA betroffen. Auch in Deutschland wird die Meniskusruptur mittlerweile als Berufskrankheit anerkannt. Die Studie ist als retrospektive Registerstudie designt. Alle Patienten wurden im Zeitraum vom 08.01.2009 bis zum 23.12.2019 am Universitätsklinikum in Würzburg operiert. Insgesamt schlossen wir 361 Patienten ein. Unter Ausschluss von Begleitverletzungen und Knochenmarksödemen konnten 41,6% der eingeschlossenen Fälle als isolierte Meniskusläsionen eingestuft werden, insbesondere bei jüngeren Patienten (<40 Jahre) ließ sich zudem ein adäquates Trauma nachweisen. Mögliche Risikofaktoren wurden auf deren Einfluss für eine Reläsion untersucht. Dabei stellte sich unter den Variablen BMI, Alter und OP-Technik lediglich letztere als ein signifikanter Faktor heraus (logRank von 0,019 5-Jahre-Follow-up; logRank von <0,001 10-Jahre- Follow-up). Die Diagnostik mittels MRT als Goldstandard und die Überprüfung derer Befunde in der Arthroskopie wiesen einen deutlichen Abfall der Sensitivität vom Innen- zum Außenmeniskus auf. Interessanter sind die Fälle, in denen eine Läsion übersehen wurde, falls auf dem anderen Meniskus eine Läsion festgestellt wurde. Zusammenfassend zeigt unsere Studie eindeutig, dass es isolierte Meniskusläsionen gibt. Auch Nahtverfahren, welche sich gerade weiterhin im Aufschwung befinden, müssten weiter auf die höheren Reläsionsraten untersucht und beobachtet werde. BMI als Risikofaktor für ein Therapieversagen bleibt weiterhin zu diskutieren auch mit Einbezug von sportlicher und körperlicher Aktivität. MRT als Goldstandard der nichtinvasiven Diagnostik wird unverändert bleiben. Jedoch sollte ein Fokus darauf geworfen werden, wann und unter welchen Umständen Läsionen übersehen werden. Dies erfordert weitere speziell dafür ausgerichtete Ausarbeitungen. N2 - The menisci are a vital part of the stability and mobility of the knee joint. Injuries to the meniscus have a high prevalence in the population. It is estimated that up to 25% of adults in the US are affected. In Germany, too, meniscus rupture is now recognized as an occupational disease. The study is designed as a retrospective registry study. All patients underwent surgery between January 8th, 2009 and December 23rd, 2019 at the University Hospital in Würzburg. In total, we included 361 patients. Excluding concomitant injuries and bone bruise, 41.6% of the included cases could be classified as isolated meniscal lesions. In addition, adequate trauma could be demonstrated, particularly in younger patients (<40 years). Possible risk factors were examined for their influence on a re-lesion. Among the variables BMI, age and surgical technique, only the latter turned out to be a significant factor (log rank of 0.019 5-year follow-up; log rank of <0.001 10-year follow-up). The diagnosis using MRI as the gold standard and the verification of their findings in arthroscopy showed a clear drop in sensitivity from the inner to the outer meniscus. More interesting are the cases where a lesion was missed if a lesion was found on the other meniscus. In summary, our study clearly shows that isolated meniscal lesions exist. Even suturing procedures, which are still on the upswing, should be further examined and observed for the higher failure rates. BMI as a risk factor for therapy failure remains to be discussed, also with the inclusion of sports and physical activity. MRI as the gold standard of non-invasive diagnostics will remain unchanged. However, a focus should be placed on when and under what circumstances lesions are missed. This requires further specially designed studies. KW - Meniskus KW - isoliert KW - Meniskusresektion KW - Meniskusläsion KW - Behandlung KW - Ätiologie KW - Reläsion KW - Meniskuschirurgie KW - MRT KW - Risikofaktoren Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-299000 ER - TY - JOUR A1 - Paul, Mila M. A1 - Mieden, Hannah J. A1 - Lefering, Rolf A1 - Kupczyk, Eva K. A1 - Jordan, Martin C. A1 - Gilbert, Fabian A1 - Meffert, Rainer H. A1 - Sirén, Anna-Leena A1 - Hoelscher-Doht, Stefanie T1 - Impact of a femoral fracture on outcome after traumatic brain injury — a matched-pair analysis of the TraumaRegister DGU\(^®\) JF - Journal of Clinical Medicine N2 - Traumatic brain injury (TBI) is the leading cause of death and disability in polytrauma and is often accompanied by concomitant injuries. We conducted a retrospective matched-pair analysis of data from a 10-year period from the multicenter database TraumaRegister DGU\(^®\) to analyze the impact of a concomitant femoral fracture on the outcome of TBI patients. A total of 4508 patients with moderate to critical TBI were included and matched by severity of TBI, American Society of Anesthesiologists (ASA) risk classification, initial Glasgow Coma Scale (GCS), age, and sex. Patients who suffered combined TBI and femoral fracture showed increased mortality and worse outcome at the time of discharge, a higher chance of multi-organ failure, and a rate of neurosurgical intervention. Especially those with moderate TBI showed enhanced in-hospital mortality when presenting with a concomitant femoral fracture (p = 0.037). The choice of fracture treatment (damage control orthopedics vs. early total care) did not impact mortality. In summary, patients with combined TBI and femoral fracture have higher mortality, more in-hospital complications, an increased need for neurosurgical intervention, and inferior outcome compared to patients with TBI solely. More investigations are needed to decipher the pathophysiological consequences of a long-bone fracture on the outcome after TBI. KW - traumatic brain injury KW - femoral fracture KW - damage control orthopedics KW - mortality Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-319363 SN - 2077-0383 VL - 12 IS - 11 ER - TY - THES A1 - Franke, Christian T1 - Gelenkknorpelintegration im Tissue Engineering: Untersuchung von Polyethylenglykol- und Hyaluronsäure-Komponenten für ein Adhäsivum und Etablierung eines biomechanischen Versuchsmodells T1 - Articular cartilage integration in tissue engineering: Investigation of polyethylene glycol and hyaluronic acid components for an adhesive and establishment of a biomechanical test model N2 - Gelenkknorpel besitzt aufgrund seiner avaskulären Natur und der fehlenden mitotischen Aktivität der Chondrozyten bei Schäden kaum Potential zur Selbstheilung. Traumatische Läsionen und degenerative Veränderungen münden im Krankheitsbild der Osteoarthrose, welches mit dem Untergang des Gelenkknorpels einhergeht. Ein neuerer Therapieansatz ist das Tissue Engineering von Gelenkknorpel, wobei jedoch die laterale Integration der Implantate mit dem nativen Knorpelgewebe problematisch bleibt. Ein Adhäsivum kann neben einer adäquaten Sofortadhäsion die Langzeitintegration fördern. In dieser Arbeit wurden verschiedene Polyethylenglykol (PEG)-basierte Zweikomponentenkleber, ausgehend vom kommerziell erhältlichen Gewebekleber CoSeal™, auf ihre Eignung für Gelenkknorpel untersucht. Dabei wurde Hyaluronsäure (HA) als physiologischer Bestandteil von Gelenkknorpel in thiolierter Form (HA-SH) als Komponente verwendet und auf seine prointegrativen Eigenschaften untersucht. Der den CoSeal™-Komponenten entsprechende 4-Succinimidyl-Glutarat/4-Thiol-PEG (4SG/4T-PEG)-Kleber hatte sich trotz seiner hohen Sofortadhäsionskraft auch nach der Substitution des 4T-PEG mit HA-SH als zu schnell in flüssiger Umgebung degradierend gezeigt, um eine suffiziente Langzeitintegration zu erreichen. Durch die Verwendung der langsamer degradierenden funktionellen 4-Succinimidyl-Carbonat-PEG (4C-PEG)-Komponente konnte die Langzeitadhäsionskraft in Kombination mit 4-Amin-PEG (4A-PEG) durch die stabilere Amid-Bindung zum einen und in Kombination mit HA-SH zum anderen signifikant gesteigert werden. Immunhistochemisch konnten bei beiden HA-haltigen Klebern Zeichen von Knorpelintegration nachgewiesen werden, während der 4C/4A-PEG-Kleber keine Integrationszeichen aufwies. Im 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromid (MTT)-Assay war bei keinem Adhäsivum eine zytotoxische Wirkung zu erkennen. Insgesamt bieten die untersuchten PEG-basierten Adhäsiva im Vergleich zu den weitverbreiteten Fibrinklebern eine deutlich höhere Sofortadhäsion, welche vergleichbar mit glutaraldehydbasierten Klebern ist. Allerdings können die initialen adhäsiven Kräfte, trotz histologisch nachweisbaren Integrationszeichen bei Inkorporation von HA, nicht langfristig aufrechterhalten werden, so dass Fibrinkleber weiterhin die Spitzengruppe in Sachen Langzeitadhäsion bilden. Da PEG eine ausgezeichnete Biokompatibilität, einfache Anwendbarkeit und zahlreiche weitere chemische Anpassungsmöglichkeiten zur Feinabstimmung der Degradationseigenschaften bietet, ist in Zukunft ein erfolgreicher Einsatz auch im Bereich von Gelenkknorpel denkbar. Für die experimentelle Untersuchung von Adhäsiva und Gelenkknorpel werden biomechanische Versuchsmodelle benötigt. Der Tensile-Test des Sandwich-Modells konnte im Rahmen dieser Arbeit erfolgreich etabliert und ein Protokoll festgelegt werden. In einem vergleichenden Versuch mit dem Push-Out-Test des Disc-Ring-Modells, welches als Referenzmodell dient, konnte in Bezug auf die Reproduzierbarkeit und Qualität der Messergebnisse die Gleichwertigkeit gezeigt werden. Insgesamt bietet er eine gute Alternative zum Push-Out-Test, um weiterführende Fragestellung, wie z.B. extrinsische Kraftwirkungen auf das Konstrukt, zu untersuchen. N2 - Articular cartilage has little potential for self-healing due to its avascular nature and the lack of mitotic activity of chondrocytes in case of damage. Traumatic injuries and degenerative changes lead to the development of osteoarthritis, which is characterized by the destruction of articular cartilage. A more recent therapeutic approach is tissue engineering of articular cartilage, but the lateral integration of implants with native cartilage tissue remains problematic. An adhesive can promote long-term integration in addition to adequate immediate adhesion. In this thesis, various polyethylene glycol (PEG)-based two-component adhesives, derived from the commercially available tissue adhesive CoSeal™, were investigated for their suitability for articular cartilage. Hyaluronic acid (HA), a physiological component of articular cartilage, was used as a component in its thiolated form (HA-SH) and examined for its pro-integrative properties. Despite its high immediate adhesive strength, the 4-succinimidyl-glutarate/4-thiol-PEG (4SG/4T-PEG) adhesive, whose components correspond to the CoSeal™ components, showed rapid degradation in a liquid environment even after substituting the 4T-PEG-component with HA-SH, which hindered sufficient long-term integration. By using the slower degrading functional 4-succinimidyl-carbonate-PEG (4C-PEG) component, the long-term adhesive strength was significantly increased in combination with 4-amine-PEG (4A-PEG) due to the resulting more stable amide bond an in combination with HA-SH. Immunohistochemical analysis showed signs of cartilage integration for both HA-containing adhesives, while the 4C/4A-PEG-adhesive showed no signs of integration. In the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, none of the adhesives exhibited cytotoxic effects. Overall, the investigated PEG-based adhesives offer a significantly higher immediate adhesive strength compared to the widely used fibrin glues, which is comparable to glutaraldehyde-based adhesives. However, despite histologically detectable signs of integration when HA was incorporated, the initial adhesive forces cannot be maintained in the long term, so fibrin glue continues to be at the forefront in terms of long-term adhesion. Since PEG offers excellent biocompatibility, easy applicability, and numerous other chemical customization options for fine-tuning degradation properties, successful use in the field of articular cartilage is conceivable in the future. For the experimental investigation of adhesives and articular cartilage, biomechanical test models are required. The tensile test of the sandwich model including a corresponding protocol was successfully established in this thesis. In a comparative experiment with the push-out test of the disc-ring model, which serves as a reference model, equivalence was demonstrated in terms of reproducibility and quality of test results. Overall, it provides a good alternative to the push-out test for investigating further questions, such as extrinsic force effects on the construct. KW - Knorpel KW - Hyaluronsäure KW - Gewebekleber KW - Polyethylenglykol KW - Knorpelintegration Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323375 ER - TY - THES A1 - Heinemann, Jonas T1 - Evaluation der aktuellen Therapie von Bandverletzungen am oberen Sprunggelenk T1 - Evaluation of the current therapy of ligament injuries of the upper ankle joint N2 - Die fibulare Kapselbandverletzung ist eine der häufigsten Verletzungen im Alltag und im Sport. Durch das hohe Patientenaufkommen mit finanziellen Auswirkungen entsteht eine Belastung für das Gesundheitssystem. Nicht selten wird die Verletzung bagatellisiert und endet in chronischen Folgen. Zur Erhebung der bis dato unklaren Versorgungsrealität führten wir eine Onlinebefragung durch. Kernfrage war, ob Einheitlichkeit in der Therapie der fibularen Kapselbandverletzung herrscht. Leitende Ärzte orthopädischer/ unfallchirurgischer Kliniken sowie GFFC-Mitglieder wurden online mittels standardisierten Fragebogens gebeten, an einer Befragung teilzunehmen. Untersuchte Faktoren waren Einsatz von Bildgebung, Ottawa Ankle Rules, Immobilisation, Belastung, Rehabilitationsmaßnahmen, OP-Indikationen, operative Techniken und generelle Handlungsleitlinien. Insgesamt 549 vollständig ausgefüllte Fragebögen wurden analysiert. Die Rückantwortquote lag bei 24,69 %. Gefragt nach der Diagnostik und Therapie unterscheiden sich die Antworten vermehrt in Abhängigkeit des jeweiligen Versorgungsstatus. Im Mittel wird die niedriggradige Verletzung mit einer Orthese oder einem Tape-/ Stützverband ruhiggestellt, die höhergradige anfangs auch mit einem Gips und im Verlauf mit einer Orthese. Drittgradig Verletzte erhalten unterstützend Unterarmgehstützen. Operiert wird bei der primären Verletzung selten. Im Falle einer OP wird in 72,5 % der Fälle arthroskopisch vorgegangen. Anhand unserer Ergebnisse wird deutlich, dass es eine grobe Behandlungspräferenz gibt: die konservative, frühfunktionelle Therapie mit einer Orthesenversorgung für vier bis sechs Wochen. Jedoch kann man von keiner Einheitlichkeit sprechen, da sich bei Teilaspekten derselben Verletzungsschwere unterschiedliche, teils widersprüchliche Behandlungspfade ergaben. Häufig unterschieden sich die Versorgungsstufen in ihrem Vorgehen. Als Problem sehen wir die fehlende Kenntnis, der zu dem Krankheitsbild gehörenden Leitlinie. Weitere Aufmerksamkeit und Aufklärung sind vonnöten. N2 - Fibular capsular ligament injury is one of the most common injuries in everyday life and in sports. The high volume of patients creates a burden with financial implications for the healthcare system. It is not uncommon for the injury to be trivialized which can cause chronic consequences. We conducted an online survey to investigate the hitherto unclear reality of care. The key question was whether there is a uniformity in the treatment of fibular capsular ligament injuries. Leading physicians of orthopedic/trauma surgery clinics and GFFC members were asked to participate in an online survey using a standardized questionnaire. Factors examined were use of imaging, Ottawa Ankle Rules, immobilization, weight bearing, rehabilitation measures, surgical indications, surgical techniques and general guidelines for action. A total of 549 completed questionnaires were analyzed. The response rate was 24.69%. When asked about diagnostics and therapy, the answers differed increasingly depending on the respective care status. On average, the low-grade injurie is immobilized with an orthosis or a tape/support bandage, the higher-grade injury is initially immobilized with a cast and later with an orthosis. Third-degree injuried patients receive supportive crutches. Surgery is rarely performed for primary injuries. In the case of surgery, arthroscopic surgery is performed in 72.5% of cases. Based on our results it becomes clear that there is a rough treatment preference: conservative, early functional therapy with an orthosis for four to six weeks. However, it is not possible to speak of uniformity, because for the same severity of injury, there are different, sometimes contradictory treatment paths for certain aspects. The care levels often differed in their approach. We see a problem in the lack of knowledge of the guideline. Further attention and education are needed. KW - Oberes Sprunggelenk KW - Sprunggelenk Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313189 ER -