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:...

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:...

Die periprothetische Fraktur ist eine schwerwiegende Komplikation nach Implantation einer Hüftendoprothese und stellt hohe Anforderungen an das Therapieregime, den Operateur und das Material. Die Wahl des Therapieverfahrenes ist vom Frakturtyp, der Knochenqualität, der Prothesenstabilität und vom Allgemeinzustand des Patienten abhängig. Die Vergleichbarkeit der Ergebnisse zwischen verschiedenen Studien wird einerseits durch die individuellen Therapiestrategien und andererseits durch die Vielzahl an unterschiedlichen Klassifikationen erschwert. Das in der vorliegenden Arbeit anhand einer Vergleichsgruppen-Analyse nachuntersuchte Studienkollektiv bestand aus n = 23 Patienten in der Hauptgruppe und n = 19 Patienten in der Kontrollgruppe, deren klinische Behandlung zwischen 2002 und 2008 am Uniklinikum Leipzig durchgeführt wurde. Hierbei handelte es sich hauptsächlich um geriatrische Patienten mit einem erhöhten Frauenanteil. Die Analyse erfolgte mit einer medianen Follow-Up Zeit der Nachuntersuchung von zwei Jahren. Im Vergleich zu in Literaturdaten angegebenen Ursachen für die Implantation einer Hüftendoprothese zeigte sich in der Hauptgruppe eine höhere Rate an Patienten mit ursprünglicher proximaler Femurfraktur im Vergleich zu Coxarthrose. Die Studie ergab darüber hinaus, dass ein hohes Patientenalter bei der Primärimplantation zu einer kürzeren Standzeit der Prothese führte (p = 0,01++). Zur periprothetischen Fraktur war häufig unterhalb der Prothesenspitze lokalisiert und in den überwiegenden Fällen durch ein Niedrig-EnergieTrauma in Verbindung mit prädisponierenden Faktoren bedingt. Im Widerspruch mit der Literatur ereignete sich die periprothetische Fraktur in unserer Untersuchung häufiger und zeitlich eher bei Patienten mit zementierter Hüftendoprothese als bei denjenigen mit nicht zementierter Endoprothese (Beals and Tower, 1996). Die operative Frakturversorgung erfolgt bei gelockerter Endoprothese durch einen Prothesenwechsel und bei fester Endoprothese durch eine Osteosynthese. Die unterschiedlichen Frakturtypen und Versorgungsarten führten nicht zu einem signifikant unterschiedlichen funktionellen Ergebnis der Patienten, wobei im Vergleich der Frakturtypen vom Trend her Patienten mit Johansson I Fraktur das beste funktionelle Resultat erreichten. Bezüglich der Komplikationsrate zeigte sich in der plattenosteosynthetisch versorgten Patientengruppe im Vergleich zu der durch einen Prothesenwechsel versorgten Gruppe eine signifikant erhöhte Rate an Revisionseingriffen. Im Unterschied zur Kontrollgruppe war die postoperative Komplikationsrate in der Hauptgruppe erhöht und das funktionelle Endergebnis in den Scoresystemen signifikant schlechter. Bei der Therapie der periprothetischen Fraktur traten trotz der guten objektiven Beweglichkeit, Schmerzen und Einschränkungen in der Gehfähigkeit auf, die zu einer deutlichen Reduktion der Alltagskompetenzen führten. Aus diesem Grund sollten die Ziele der Therapie periprothetischer Frakturen in der Frakturprävention, Therapieoptimierung und Nachsorgeverbesserung liegen. Zu achten ist dabei auf eine individuell ausreichende postoperative Schmerztherapie und intensive frühfunktionelle physiotherapeutische Behandlung mit Förderung der Selbstständigkeit, wobei eine weitere wissenschaftliche Begleitung und Analyse der Behandlungsergebnisse zukünftig wünschenswert wäre.:Inhaltsverzeichnis 1 EINLEITUNG ...................................................................................................................................... 8 1.1 EINFÜHRUNG IN DIE THEMATIK ............................................................................................................ 8 1.2 ÄTIOLOGIE UND RISIKOFAKTOREN ....................................................................................................... 9 1.3 DIAGNOSTIK ..................................................................................................................................... 11 1.4 EINTEILUNGEN UND KLASSIFIKATIONEN ............................................................................................. 12 1.5 THERAPIE ......................................................................................................................................... 18 1.5.1 Prothesenwechsel ..................................................................................................................... 20 1.5.2 Plattenosteosynthese ................................................................................................................ 21 1.5.3 Retrograder Verriegelungsmarknagel ....................................................................................... 23 1.5.4 Fixateur externe ....................................................................................................................... 23 1.5.5 Cerclagen ............................................................................................................................... 24 1.5.6 Allgemeine Behandlungsziele ................................................................................................... 24 1.6 KOMPLIKATIONEN ............................................................................................................................. 25 1.7 FRAGESTELLUNG UND HYPOTHESE ..................................................................................................... 26 2 PATIENTEN UND METHODIK ........................................................................................................ 28 2.1 PATIENTENKOLLEKTIV ....................................................................................................................... 28 2.1.1 Hauptgruppe ............................................................................................................................ 28 2.2 KONTROLLGRUPPE ............................................................................................................................. 29 2.3 DATENERHEBUNG .............................................................................................................................. 30 2.4 DATENERFASSUNG ............................................................................................................................. 31 2.4.1 Fragebogen zur Krankengeschichte .......................................................................................... 31 2.4.2 Oxford Hip Score ..................................................................................................................... 31 2.4.3 Merle d´Aubigné-Score ............................................................................................................ 32 2.4.4 Harris Hip Score ...................................................................................................................... 33 2.5 STATISTIK ........................................................................................................................................ 35 3 ERGEBNISSE .................................................................................................................................... 37 3.1 HAUPTGRUPPE .................................................................................................................................. 37 3.1.1 Allgemeine Gruppenmerkmale .................................................................................................. 37 3.1.2 Art und Indikation der Endoprothese ........................................................................................ 39 3.1.3 Klassifikation und Trauma ....................................................................................................... 42 3.1.4 Komplikationen ........................................................................................................................ 50 3.1.5 Nachuntersuchungsergebnisse Hauptgruppe............................................................................. 53 3.1.6 Vergleich der Scoreergebnisse.................................................................................................. 63 3.2 KONTROLLGRUPPE ............................................................................................................................. 64 3.2.1 Allgemeine Gruppenmerkmale .................................................................................................. 64 7/ 112 3.2.2 Art und Indikation der Endoprothese ........................................................................................ 65 3.2.3 Komplikationen ........................................................................................................................ 67 3.2.4 Nachuntersuchungsergebnisse Kontrollgruppe ......................................................................... 68 3.3 VERGLEICH DER ERGEBNISSE VON HAUPT- UND KONTROLLGRUPPE .................................................... 74 4 DISKUSSION ..................................................................................................................................... 76 4.1 ALLGEMEINE GRUPPENMERKMALE..................................................................................................... 76 4.2 INDIKATION DER ENDOPROTHESE UND STANDZEIT .............................................................................. 78 4.3 PERIPROTHETISCHE FRAKTUR ............................................................................................................ 79 4.5 POSTOPERATIVER VERLAUF ............................................................................................................... 82 4.6 ERGEBNISSE DER NACHUNTERSUCHUNG ............................................................................................. 84 4.7 AUSBLICK ........................................................................................................................................ 87 5 ZUSAMMENFASSUNG ..................................................................................................................... 89 6 LITERATURVERZEICHNIS ............................................................................................................. 91 7 ABBILDUNGSVERZEICHNIS .......................................................................................................... 98 8 TABELLENVERZEICHNIS ............................................................................................................ 100 9 ABKÜRZUNGSVERZEICHNIS ...................................................................................................... 101 10 ANLAGEN ........................................................................................................................................ 102 10.1 OXFORD HIP SCORE .................................................................................................................... 102 10.2 SCORE NACHMERLE DÁUBIGNÉ UND POSTEL............................................................................... 104 10.3 HARRIS HIP SCORE ...................................................................................................................... 105 10.4 FRAGEBOGEN-PRIMÄRPROTHESE ................................................................................................. 106 10.5 FRAGEBOGEN-PERIPROTHETISCHE FRAKTUR ................................................................................ 108 11 ERKLÄRUNG ÜBER DIE EIGENSTÄNDIGE ABFASSUNG DER ARBEIT ............................... 110 12 DANKSAGUNG ............................................................................................................................... 111 13 LEBENSLAUF ................................................................................................................................. 112

Background: Modular mega-endoprosthesis systems are used to bridge very large bone defects and have become a widespread method in orthopaedic surgery for the treatment of tumours and revision arthroplasty. However, the indications for the use of modular mega-endoprostheses must be carefully considered. Implanting modular endoprostheses requires major, complication-prone surgery in which the limited salvage procedures should always be borne in mind. The management of periprosthetic infection is particularly difficult and beset with problems. Given this, the present study was designed to gauge the significance of periprosthetic infections in connection with modular mega-implants in the lower extremities among our own patients. Methods: Patients who had been fitted with modular endoprosthesis on a lower extremity at our department between September 1994 and December 2011 were examined retrospectively. A total of 101 patients with 114 modular prostheses were identified. Comprising 30 men (29.7 %) and 71 women (70.3 %), their average age at the time of surgery was 67 years (18–92 years). Results: The average follow-up period was 27 months (5 months and 2 weeks to 14 years and 11 months) and the drop-out rate was about 8.8 %. Altogether, there were 19 (17.7 %) endoprosthesis infections: 3 early infections and 16 late or delayed infections. The pathogen spectrum was dominated by coagulase-negative staphylococci (36 %) and Staphylococcus aureus (16 %), including 26 % multi-resistant pathogens. Reinfection occurred in 37 % of cases of infection. Tumours were followed by significantly fewer infections than the other indications. Infections were twice as likely to occur after previous surgery. Conclusion: In our findings modular endoprostheses (18 %) are much more susceptible to infection than primary endoprostheses (0.5–2,5 %). Infection is the most common complication alongside the dislocation of proximal femur endoprostheses. Consistent, radical surgery is essential – although even with an adequate treatment strategy, the recurrence rate is very high. Unfortunately, the functional results are frequently unsatisfactory, with amputation often being the last resort. Therefore, the indication for implantation must be carefully considered and discussed in great detail, especially in the case of multimorbid patients with previous joint infections.

<p>Current stabilization methods for periprosthetic fractures of the distal femur have been inadequate in achieving sufficient fixation and can lead to complications rates as high as 29%. Therefore, the overall objective of this study was to design, manufacture and evaluate (experimentally and computationally) a novel plating method for improving the treatment of periprosthetic fractures of the distal femur.</p> <p>Medial and lateral prototype plates were designed and manufactured based on the geometry of a synthetic femur and a femoral prosthesis. The two plates were linked via a compression screw and a small tab on each plate that inserts into pre-existing slots on the prosthesis to enhance rigidity of the construct. Synthetic femurs were used to assess the ability of the prototype plates to stabilize a periprosthetic fracture compared to a traditional single lateral plate. Each femur was subjected to a testing protocol that involved compressive and bending loading of the sample. The relative motion between the distal and proximal fragments during loading was then measured using both 2D and 3D motion tracking techniques. Both techniques revealed that the prototype bilateral plates were able to reduce motion of the fracture site compared to a single lateral plate.</p> <p>The final objective concerned the development of a finite element model to represent the experimental testing. The fracture gap motion obtained from the final model did not completely agree with the experimental data; however, additional experimental measurements found that the majority of these differences could be attributed to simplification made at the tab-slot interaction. Despite the difference, the model represents a significant step forward in the simulation of periprosthetic fracture treatment, and further refinement would allow for optimization of the plate design.</p> <p>Overall, the results of this thesis indicate that an alternative approach to treating periprosthetic fractures exists that is capable of improving fracture stabilization.</p> / Master of Applied Science (MASc)

Total hip and knee arthroplasty surgeries form an integral part of orthopaedic practice. With an increase of the primary arthroplasty surgeries performed, comes also an increase in the number of complications. The most common complications of these otherwise very successful procedures is periprosthetic joint infections which are also one of the most difficult to treat. In the first part of the study, we evaluated the primary bacterial resistance of the 14 most commonly used materials in the construction of joint prostheses. More specifically, we concentrated on how their surface treatment resists colonisation by specific bacterial species (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterococcus faecalis and Escherichia coli). The studied materials included metal alloys that are commonly used in the weight bearing parts of implants - CoCrNo, FeNiCr and Ti6A14V - but also polymeric and ceramic materials used in the bearing materials, represented by ultra-high- molecular-weight polyethylene (UHMWPE) and aluminium oxide (Al2O3). Our aim was to assess the relationship between material surface roughness and the sensitivity to colonisation by specific bacterial strains and to evaluate their affinity to different materials. Previous studies have proven that the roughness of...

Background: Modular mega-endoprosthesis systems are used to bridge very large bone defects and have become a widespread method in orthopaedic surgery for the treatment of tumours and revision arthroplasty. However, the indications for the use of modular mega-endoprostheses must be carefully considered. Implanting modular endoprostheses requires major, complication-prone surgery in which the limited salvage procedures should always be borne in mind. The management of periprosthetic infection is particularly difficult and beset with problems. Given this, the present study was designed to gauge the significance of periprosthetic infections in connection with modular mega-implants in the lower extremities among our own patients. Methods: Patients who had been fitted with modular endoprosthesis on a lower extremity at our department between September 1994 and December 2011 were examined retrospectively. A total of 101 patients with 114 modular prostheses were identified. Comprising 30 men (29.7 %) and 71 women (70.3 %), their average age at the time of surgery was 67 years (18–92 years). Results: The average follow-up period was 27 months (5 months and 2 weeks to 14 years and 11 months) and the drop-out rate was about 8.8 %. Altogether, there were 19 (17.7 %) endoprosthesis infections: 3 early infections and 16 late or delayed infections. The pathogen spectrum was dominated by coagulase-negative staphylococci (36 %) and Staphylococcus aureus (16 %), including 26 % multi-resistant pathogens. Reinfection occurred in 37 % of cases of infection. Tumours were followed by significantly fewer infections than the other indications. Infections were twice as likely to occur after previous surgery. Conclusion: In our findings modular endoprostheses (18 %) are much more susceptible to infection than primary endoprostheses (0.5–2,5 %). Infection is the most common complication alongside the dislocation of proximal femur endoprostheses. Consistent, radical surgery is essential – although even with an adequate treatment strategy, the recurrence rate is very high. Unfortunately, the functional results are frequently unsatisfactory, with amputation often being the last resort. Therefore, the indication for implantation must be carefully considered and discussed in great detail, especially in the case of multimorbid patients with previous joint infections.

No description available.

La pose d’implants mammaires est l’une des interventions chirurgicales les plus courantes en chirurgie plastique. Elle permet de reconstruire un sein après une mastectomie ou d’augmenter son volume pour améliorer le décolleté et la forme du sein. Depuis leur introduction dans les années 1960, les implants mammaires siliconés ont fait l’objet de multiples controverses et leur innocuité a pendant longtemps été questionnée. Ces dispositifs médicaux sont considérés comme sûr par la FDA mais ne sont pas pour autant exempts de complications. L’une d’entre elles, le silicone bleeding, se traduit par la migration de particules de silicone depuis le gel de l’implant vers la capsule péri-prothétique. Ces particules de silicone représentent une source potentielle d’inflammation chronique autour des implants mammaires dont les conséquences à long terme sur la santé des patientes ne sont pas claires. Bien que cette complication soit objectivée depuis les années 1970, il existe à l’heure actuelle peu de données sur la quantité de silicone qui est susceptible de migrer des implants mammaires. L’objectif principal de notre étude a été de quantifier les particules de silicone dans les capsules péri-prothétiques des implants mammaires en décrivant une nouvelle méthode de quantification basée sur une analyse histologique approfondie des spécimens de capsule. Les résultats préliminaires de notre étude ont permis de démontrer que des millions de particules de silicone peuvent diffuser dans la capsule péri-prothétique des implants mammaires siliconés et que l’ampleur du phénomène à tendance à croître avec la durée d’implantation. / The placement of breast implants is one of the most common surgical procedures in the field of plastic surgery. Although these medical devices are considered safe by the FDA, their use is not free of complications. One of these complications is silicone particle bleeding, or the migration of silicone particles from the breast implant into the peri-prosthetic capsule. These particles represent a potential source of chronic inflammation around breast implants, with unclear long-term consequences for patient health. Although this complication has been observed since the 1970s, there is currently very little data on the amount of silicone that is likely to migrate from breast implants. The primary objective of this study was to quantify silicone particles in the peri-prosthetic capsules of breast implants by describing a new method of quantification based on a thorough histological analysis of capsule specimens. Preliminary results of our study have shown that millions of silicone particles can diffuse into the periprosthetic capsule of silicone breast implants and that the amount of silicone particles tends to increase with the duration of implantation.

Polymethylmethacrylate (PMMA) removal during septic total joint arthroplasty revision is associated with a high fracture and perforation risk. Ultrasonic cement removal is considered a bone-preserving technique. Currently, there is still a lack of sound data on efficacy as it is difficult to detect smaller residues with reasonable technical effort. However, incomplete removal is associated with the risk of biofilm coverage of the residue. Therefore, the study aimed to investigate the efficiency of ultrasonic-based PMMA removal in a human cadaver model. The femoral components of a total hip and a total knee prosthesis were implanted in two cadaver femoral canals by 3rd generation cement fixation technique. Implants were then removed. Cement mantle extraction was performed with the OSCAR-3-System ultrasonic system (Orthofix®). Quantitative analysis of cement residues was carried out with dual-energy and microcomputer tomography. With a 20 µm resolution, in vitro microcomputer tomography visualized tiniest PMMA residues. For clinical use, dual-energy computer tomography tissue decomposition with 0.75 mm resolution is suitable. With ultrasound, more than 99% of PMMA was removed. Seven hundred thirty-four residues with a mean volume of 0.40 ± 4.95 mm3 were identified with only 4 exceeding 1 cm in length in at least one axis. Ultrasonic cement removal of PMMA was almost complete and can therefore be considered a highly effective technique. For the first time, PMMA residues in the sub-millimetre range were detected by computer tomography. Clinical implications of the small remaining PMMA fraction on the eradication rate of periprosthetic joint infection warrants further investigations.