TY - JOUR A1 - Steinert, Andre F. A1 - Rudert, Maximilian A1 - Sieker, Jakob T. T1 - "Symptomatic loosening of a total knee arthroplasty caused by a tibial chondrosarcoma – a case report" N2 - Premature implant loosening following total knee arthroplasty (TKA) can have several causes. In this article we report on a rare case of a 74 year old male patient suffering tibial component loosening 14 month after primary TKA. The patient did neither have any malignancies nor joint arthroplasty before. Upon clinical examination the range of motion in the diseased knee was painfully restricted to 80° of knee flexion, with the patient increasingly suffering sleeping and resting pain, and also at weight bearing. In standard radiographs, loosening of the TKA due to a large osteolysis at the tibial component was evident. Local computed tomography (CT) of the right knee revealed loosening of the tibial component due to a presumably malign bone tumor. For determination of the final diagnosis a representative biopsy of the tumor was taken by open surgery prior to the tumor resection. Histopathologic evaluation of the biopsy revealed a periprosthetic myxoid chondrosarcoma of the proximal tibia. Pre-operative staging examination included CT scans of lung and abdomen, as well as a bone scintigraphy which revealed no signs of tumor metastasis in the body. Surgical management comprised wide tumor resection and implantation of a hinged tumor knee arthroplasty with replacements of the distal femur and proximal tibia, as well as a patella tendon replacement using a synthetic ligament. Revision surgery was necessary twice due to impaired wound healing and critical soft tissue coverage, and treatment included a gastrocnemius muscle flap with skin mesh graft covering. Unfortunately long-term follow-up examinations could not be obtained, as the patient deceased due to an alveolitis during rehabilitation. In summary, the specifics of this rare case of aseptic TKA loosening, and the unusual circumstances of chondrosarcoma diagnosis and treatment are informative for those providing surgical treatment of similar cases. KW - Total knee arthroplasty KW - Bone tumor KW - Chondrosarcoma KW - Aseptic loosening Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110341 ER - TY - JOUR A1 - Klotz, Barbara A1 - Mentrup, Birgit A1 - Regensburger, Martina A1 - Zeck, Sabine A1 - Schneidereit, Jutta A1 - Schupp, Nicole A1 - Linden, Christian A1 - Merz, Cornelia A1 - Ebert, Regina A1 - Jakob, Franz T1 - 1,25-Dihydroxyvitamin D3 Treatment Delays Cellular Aging in Human Mesenchymal Stem Cells while Maintaining Their Multipotent Capacity JF - PLoS ONE N2 - 1,25-dihydroxyvitamin D3 (1,25D3) was reported to induce premature organismal aging in fibroblast growth factor-23 (Fgf23) and klotho deficient mice, which is of main interest as 1,25D3 supplementation of its precursor cholecalciferol is used in basic osteoporosis treatment. We wanted to know if 1,25D3 is able to modulate aging processes on a cellular level in human mesenchymal stem cells (hMSC). Effects of 100 nM 1,25D3 on hMSC were analyzed by cell proliferation and apoptosis assay, beta-galactosidase staining, VDR and surface marker immunocytochemistry, RT-PCR of 1,25D3-responsive, quiescence-and replicative senescence-associated genes. 1,25D3 treatment significantly inhibited hMSC proliferation and apoptosis after 72 h and delayed the development of replicative senescence in long-term cultures according to beta-galactosidase staining and P16 expression. Cell morphology changed from a fibroblast like appearance to broad and rounded shapes. Long term treatment did not induce lineage commitment in terms of osteogenic pathways but maintained their clonogenic capacity, their surface marker characteristics (expression of CD73, CD90, CD105) and their multipotency to develop towards the chondrogenic, adipogenic and osteogenic pathways. In conclusion, 1,25D3 delays replicative senescence in primary hMSC while the pro-aging effects seen in mouse models might mainly be due to elevated systemic phosphate levels, which propagate organismal aging. KW - perspectives KW - bone marrow KW - mutant mice KW - oxidative stress KW - transcription factors KW - vitamin-D-receptor KW - differentiation KW - tissue KW - 2',7'-dichlorofluorescin KW - homeostasis Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133392 VL - 7 IS - 1 ER - TY - THES A1 - Braag, Aaron T1 - 10 Jahres Ergebnisse nach muskelschonendem modifiziertem Watson Jones Zugang bei der Implantation von Hüfttotalendoprothesen T1 - 10-year results after a muscle-sparing modified Watson Jones approach in total hip arthroplasty N2 - Bei der Implantation von Hüfttotalendoprothesen (HTEP) finden seit etwa 15 Jahren minimalinvasive muskelschonende Zugänge zunehmend Verwendung. Langfristige Daten der Zugänge, insbesondere des minimalinvasiven anterolateralen Zuganges nach Watson-Jones (ALMI) sind in der Literatur bisher nur unzureichend vorhanden. Methodik: Ziel dieser Studie war es ein Kollektiv nach HTEP Implantation mit ALMI Zugang mit einem Kollektiv nach HTEP Implantation mit lateralem Zugang nach 10 Jahren hinsichtlich Gelenksfunktion, Muskelfunktion, Zufriedenheit und radiologischer Parameter zu vergleichen und etwaige Unterschiede in der Langzeitbilanz zu detektieren. Zwei Kollektive mit jeweils 29 operierten Hüftgelenken, Erstimplantation durch die gleichen Operateure in den Jahren 2005 bis 2008, wurden im Diakoniewerk München-Maxvorstadt nachuntersucht. Die dafür herangezogenen Parameter waren Harris Hip Score, Forgotten Joint Score-12, klinische Prüfung des Trendelenburg Zeichens, postoperative Röntgenbildgebung, Auftreten von Komplikationen und Narbenlänge. Ergebnisse & Schlussfolgerungen: Die beiden Kollektive zeigten in den Parametern Harris Hip Score, Forgotten Joint Score und klinische Prüfung des Trendelenburg Zeichens geringfügige Unterschiede zugunsten des ALMI Kollektivs, die jedoch nicht signifikant waren. Beide Kollektive erreichten in den beschriebenen Scores sehr gute bis exzellente Ergebnisse nach 10 Jahren. Das geringere Auftreten eines auffälligen Trendelenburg Zeichens im ALMI Kollektiv (13,8 vs. 6,9 %) gibt Hinweise auf eine verbesserte Funktion der Glutealmuskulatur durch die intraoperative Muskelschonung. Die beiden Zugänge zeigten in den radiologischen Parametern und der Komplikationsrate ebenbürtige Ergebnisse. Vermehrte Fehlpositionierungen wurden im ALMI Kollektiv nicht beobachtet. Unsere Beobachtungen passen zu den wenigen vorhandenen in der Literatur beschriebenen Ergebnissen von minimalinvasiven muskelschonenden Zugängen in der Langzeitbilanz. N2 - Minimally invasive, muscle-sparing approaches have been increasingly used for the implantation of total hip endoprostheses (HTEP) for about 15 years. Long-term data on the approaches, in particular the minimally invasive anterolateral approach according to Watson-Jones (ALMI), is currently absent in the literature. Methods: The aim of this study was to compare a collective after THA implantation with ALMI approach with a collective after THA implantation with lateral approach after 10 years regarding joint function, muscle function, satisfaction and radiological parameters and detect any differences in the long-term period. Two collectives, each with 29 operated hip joints, first implantation by the same surgeons in the years 2005 to 2008, were followed up in the Diakoniewerk Munich-Maxvorstadt. The parameters used were Harris Hip Score, Forgotten Joint Score-12, clinical assessment of the Trendelenburg sign, postoperative X-ray imaging, occurrence of complications and scar length. Results & Conclusions: The two collectives showed slight differences in favor of the ALMI collective in the parameters Harris Hip Score, Forgotten Joint Score and clinical examination of the Trendelenburg sign, but these were not significant. Both collectives achieved very good to excellent results in the described scores after 10 years. The lower occurrence of a noticeable Trendelenburg sign in the ALMI collective (13.8 vs. 6.9%) indicates an improved function of the gluteal muscles through intraoperative muscle protection. The two approaches showed equal results in the radiological parameters and the complication rate. Increased incorrect positioning was not observed in the ALMI collective. Our observations match the few existing results of minimally invasive, muscle-sparing approaches in the long-term period, which are described in the literature. KW - Minimalinvasiv KW - Hüftgelenkprothese KW - Hüft-TEP KW - anterolateral KW - MIS KW - Langzeit Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281416 ER - TY - THES A1 - Bockholt, Martin T1 - 9-11 Jahres Ergebnisse nach zementierter Titanschaft-Prothese (Müller-Geradschaftprothese) T1 - 9 -11 years results of cemented titanium Mueller straight stem in total hip replacement N2 - In den letzten Jahrzehnten ist die Anzahl der degenerativen Gelenkerkrankungen wie die Coxarthrose und somit die Zahl der zu implantierenden Hüfttotalendoprothesen stark gestiegen. Ziel der vorliegenden Arbeit ist es, langfristige Ergebnisse zementierter Titanschaftprothesen in Bezug auf aseptische Lockerungen zu ermitteln. Von den in der Orthopädischen Universitätsklinik Würzburg implantierten Hüfttotalendoprothesen von Januar 1990 bis März 1992 konnten nach durchschnittlich 9 Jahren 110 Hüfttotalendoprothesen klinisch und radiologisch nachuntersucht werden. Zum Zeitpunkt der Kontrolluntersuchung hatten die Patienten ein mittleres Alter von 76 Jahren. In allen Fällen wurden Müller-Geradschaftprothesen mit einer Ti-6A1-7Nb-Legierung in matter Oberfläche, Biolox®-Keramik-Köpfe sowie Knochenzement Palacos-® verwendet. Es wurde bei 4 Hüft-TEPs wegen aseptischer Lockerung ein Prothesenwechsel durchgeführt. Das nachuntersuchte Patientengut wurde in 3 Gruppen eingeteilt. Gruppe A rekrutierte sich aus denjenigen Patienten, bei denen keine radiologischen Lockerungszeichen erkennbar waren. Die Patienten mit mehr als einem Lysesaum jedoch mit festem Sitz der Schaftprothese im Vergleich zu den postoperativen Röntgenbildern wurden der Gruppe B zugeordnet. Letztendlich bildeten die Patienten mit ausgeprägten Lockerungszeichen bzw. vollständig gelockerte Prothesen die Gruppe C. Der Harris-Hip-Score der Gruppe A mit 85 ( 13) Punkten und der Gruppe B mit 86 ( 14) Punkten zeigte gute Ergebnisse. Der Harris-Score lag in der Gruppe C bei 76 (± 5) Punkten und erreichte somit ein mäßiges Ergebnis. Im Vergleich zu den Gruppen A und B erwies sich diese Punktezahl als signifikant schlechter. Die Patienten mit ausgeprägten Lockerungszeichen waren signifikant jünger (im Mittel 6 Jahre) als die der Gruppe ohne Lockerungssäume. Ebenfalls fanden wir einen signifikanten Unterschied im Bezug auf das Körpergewicht, Körpergewicht im Verhältnis zu zementierter Schaftoberfläche und Harris-Score (88 vs. 75 kg; 1,5 vs. 1,0 kg/cm; 76 vs. 85). Für Geschlecht, Schaftgröße, Schaftart, Aktivität, heterotope Ossifikationen und Body-Maß-Index traf dies nicht zu. Unter Berücksichtigung der erhobenen Daten (Harris-Hüft-Score und Quotient des Körpergewichts zur zementierten Schaftoberfläche) sollte eine möglichst große Prothese implantiert werden, um das Körpergewicht auf eine große Schaftoberfläche zu verteilen. Insgesamt hat sich die zementierte Müller-Geradschaftprothese aus Titanlegierung bewährt, so dass sie für die Behandlung von Nickelallergiker zu empfehlen ist. N2 - The purpose of this study was to obtain 9-11years results after total hip arthroplasty (THA) with cemented titanium stems (Mueller-Straight-Stem). 91 patients with a total of 110 THA were examined clinically and radiologically after an average follow-up of 9,5 years. Revisions for aseptic loosening were carried out in 4 cases (4%). Subsidence or varus position could only be observed in one of these cases. Radiolucent lines (RLL) were found in 37 cases, mainly located around the proximal zones of the stem (zone 1, 7, 8 and 14). The clinical results in the Harris score were good or excellent in 78% and satisfactory in 20% of the cases. The body weight was significantly higher (88 kg; d=5.4) in the 4 patients with aseptic loosening, compared to patients without RLL (75kg; d=15), especially the ratio body weight to surface of the stem showed a significant difference (1.5 kg/cm2 versus 1 kg/cm2; p<0.05). No significant differences were found in other factors, including sex, size or type of stem, Harris-score, heterotopic ossification or body-mass index. Good long-term results can be achieved with cemented titanium stem implants. In conclusion, this titanium implant may be recommended for patients with hypersensitivity against Chrome, Cobalt and Nickel. Implanting the biggest possible stem seems to be most beneficial. KW - Aseptische Lockerung KW - Hüftgelenk KW - Prothese KW - zementierte Hüfttotalendoprothesen KW - radiologische Lysesäume KW - Körpergewicht im Verhältnis zu zementierter Schaftoberfläche KW - total hip arthroplasty KW - radiolucent lines KW - aseptic loosening KW - ratio body weight to surface of the stem Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37635 ER - TY - JOUR A1 - Reichert, Johannes C. A1 - von Rottkay, Eberhard A1 - Roth, Franz A1 - Renz, Tim A1 - Hausmann, Johannes A1 - Kranz, Julius A1 - Rackwitz, Lars A1 - Nöth, Ulrich A1 - Rudert, Maximilian T1 - A prospective randomized comparison of the minimally invasive direct anterior and the transgluteal approach for primary total hip arthroplasty JF - BMC Musculoskeletal Disorders N2 - Background: The presented prospective randomized controlled single-centre study compares the clinical outcome up to 12 months after total hip arthroplasty using a minimally invasive single-incision direct anterior (DAA) and a direct transgluteal lateral approach. Methods: A total of 123 arthroplasties were evaluated utilizing the Harris Hip Score (HHS), the extra short musculoskeletal functional assessment questionnaire (XSFMA), the Short Form 36 (SF-36) health survey, a Stepwatch™ Activity Monitor (SAM), and a timed 25 m foot walk (T25-FW). Postoperative x-ray images after THA were reviewed to determine inclination and stem positioning. Results: At final follow-up, the XSFMA functional index scores were 10.3 (anterior) and 15.08 (lateral) while the bother index summed up to a score of 15.8 (anterior) and 21.66 (lateral) respectively, thus only differing significantly for the functional index (p = 0.040 and p = 0.056). The SF-36 physical component score (PCS) was 47.49 (anterior) and 42.91 (lateral) while the mental component score (MCS) summed up to 55.0 (anterior) and 56.23 (lateral) with a significant difference evident for the PCS (p = 0.017; p = 0.714). Patients undergoing THA through a DAA undertook a mean of 6402 cycles per day while those who had undergone THA through a transgluteal approach undertook a mean of 5340 cycles per day (p = 0.012). Furthermore, the obtained outcome for the T25-FW with 18.4 s (anterior) and 19.75 s (lateral) and the maximum walking distance (5932 m and 5125 m) differed significantly (p = 0.046 and p = 0.045). The average HHS showed no significant difference equaling 92.4 points in the anterior group and 91.43 in the lateral group (p = 0.477). The radiographic analysis revealed an average cup inclination of 38.6° (anterior) and 40.28° (lateral) without signs of migration. Conclusion: In summary, our outcomes show that after 1 year THA through the direct anterior approach results in a higher patient activity compared to THA utilizing a transgluteal lateral approach while no differences regarding hip function are evident. KW - total hip arthroplasty KW - direct anterior approach KW - minimally invasive KW - transgluteal approach KW - prospective study Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176072 VL - 19 IS - 241 ER - TY - JOUR A1 - Seefried, Lothar A1 - Mueller-Deubert, Sigrid A1 - Schwarz, Thomas A1 - Lind, Thomas A1 - Mentrup, Birgit A1 - Kober, Melanie A1 - Docheva, Denitsa A1 - Liedert, Astrid A1 - Kassem, Moustapha A1 - Ignatius, Anita A1 - Schieker, Matthias A1 - Claes, Lutz A1 - Wilke, Winfried A1 - Jakob, Franz A1 - Ebert, Regina T1 - A small scale cell culture system to analyze mechanobiology using reporter gene constructs and polyurethane dishes N2 - Mechanical forces are translated into biochemical signals and contribute to cell differentiation and phenotype maintenance. Mesenchymal stem cells and their tissuespecific offspring, as osteoblasts and chondrocytes, cells of cardiovascular tissues and lung cells are sensitive to mechanical loading but molecules and mechanisms involved have to be unraveled. It is well established that cellular mechanotransduction is mediated e.g. by activation of the transcription factor SP1 and by kinase signaling cascades resulting in the activation of the AP1 complex. To investigate cellular mechanisms involved in mechanotransduction and to analyze substances, which modulate cellular mechanosensitivity reporter gene constructs, which can be transfected into cells of interest might be helpful. Suitable small-scale bioreactor systems and mechanosensitive reporter gene constructs are lacking. To analyze the molecular mechanisms of mechanotransduction and its crosstalk with biochemically induced signal transduction, AP1 and SP1 luciferase reporter gene constructs were cloned and transfected into various cell lines and primary cells. A newly developed bioreactor and small-scale 24-well polyurethane dishes were used to apply cyclic stretching to the transfected cells. 1 Hz cyclic stretching for 30 min in this system resulted in a significant stimulation of AP1 and SP1 mediated luciferase activity compared to unstimulated cells. In summary we describe a small-scale cell culture/bioreactor system capable of analyzing subcellular crosstalk mechanisms in mechanotransduction, mechanosensitivity of primary cells and of screening the activity of putative mechanosensitizers as new targets, e.g. for the treatment of bone loss caused by both disuse and signal transduction related alterations of mechanotransduction. KW - Bioreaktor KW - Mechanical strain KW - mechanosensitive reporter KW - gene constructs KW - bioreactor Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68099 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Dhaliwal, Anand A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - A surgeon that switched to unrestricted kinematic alignment with manual instruments has a short learning curve and comparable resection accuracy and outcomes to those of an experienced surgeon JF - Journal of Personalized Medicine N2 - After starting an orthopedic practice, a surgeon with a fellowship in mechanically aligned (MA) TKA initiated this study to characterize their learning curve after they switched to unrestricted kinematic alignment (KA) TKA using manual instruments. Accordingly, the present study determined for the inexperienced (IE) surgeon the number of cases required to achieve consistent femoral resections and operating times, and whether the femoral resection accuracy, patient-reported outcome measures (PROMs), and component alignment were different from an experienced (E) surgeon. This prospective cohort study analyzed the IE surgeon's first 30 TKAs, all performed with KA, and 30 consecutive KA TKAs performed by an E surgeon. The resection accuracy or deviation was the calipered thickness of the distal and posterior medial and lateral femoral resections minus the planned resection thickness, which was the thickness of the corresponding condyle of the femoral component, minus 2 mm for cartilage wear, and 1 mm for the kerf of the blade. Independent observers recorded the femoral resection thickness, operative times, PROMs, and alignment. For each femoral resection, the deviation between three groups of patients containing ten consecutive KA TKAs, was either insignificant (p = 0.695 to 1.000) or within the 0.5 mm resolution of the caliper, which indicated no learning curve. More than three groups were needed to determine the learning curve for the operative time; however, the IE surgeon's procedure dropped to 77 min for the last 10 patients, which was 20 min longer than the E surgeon. The resection deviations of the IE and E surgeon were comparable, except for the posterolateral femoral resection, which the IE surgeon under-resected by a mean of −0.8 mm (p < 0.0001). At a mean follow-up of 9 and 17 months, the Forgotten Joint Score, Oxford Knee Score, KOOS, and the alignment of the components and limbs were not different between the IE and E surgeon (p ≥ 0.6994). A surgeon that switches to unrestricted KA with manual instruments can determine their learning curve by computing the deviation of the distal and posterior femoral resections from the planned resection. Based on the present study, an IE surgeon could have resection accuracy, post-operative patient outcomes, and component alignment comparable to an E surgeon. KW - total knee arthroplasty KW - kinematic alignment KW - learning curve KW - accuracy KW - efficiency Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281842 SN - 2075-4426 VL - 12 IS - 7 ER - TY - JOUR A1 - Thibaudeau, Laure A1 - Taubenberger, Anna V. A1 - Holzapfel, Boris M. A1 - Quent, Verena M. A1 - Fuehrmann, Tobias A1 - Hesami, Parisa A1 - Brown, Toby D. A1 - Dalton, Paul D. A1 - Power, Carl A. A1 - Hollier, Brett G. A1 - Hutmacher, Dietmar W. T1 - A tissue-engineered humanized xenograft model of human breast cancer metastasis to bone JF - Disease Models & Mechanisms N2 - The skeleton is a preferred homing site for breast cancer metastasis. To date, treatment options for patients with bone metastases are mostly palliative and the disease is still incurable. Indeed, key mechanisms involved in breast cancer osteotropism are still only partially understood due to the lack of suitable animal models to mimic metastasis of human tumor cells to a human bone microenvironment. In the presented study, we investigate the use of a human tissue-engineered bone construct to develop a humanized xenograft model of breast cancer-induced bone metastasis in a murine host. Primary human osteoblastic cell-seeded melt electrospun scaffolds in combination with recombinant human bone morphogenetic protein 7 were implanted subcutaneously in non-obese diabetic/severe combined immunodeficient mice. The tissue-engineered constructs led to the formation of a morphologically intact 'organ' bone incorporating a high amount of mineralized tissue, live osteocytes and bone marrow spaces. The newly formed bone was largely humanized, as indicated by the incorporation of human bone cells and human-derived matrix proteins. After intracardiac injection, the dissemination of luciferase-expressing human breast cancer cell lines to the humanized bone ossicles was detected by bioluminescent imaging. Histological analysis revealed the presence of metastases with clear osteolysis in the newly formed bone. Thus, human tissue-engineered bone constructs can be applied efficiently as a target tissue for human breast cancer cells injected into the blood circulation and replicate the osteolytic phenotype associated with breast cancer-induced bone lesions. In conclusion, we have developed an appropriate model for investigation of species-specific mechanisms of human breast cancer-related bone metastasis in vivo. KW - breast cancer KW - bone metastasis KW - humanized xenograft model KW - melt electrospinning KW - tissue engineering KW - osteotropism KW - in vivo KW - stem-cell niche KW - human prostate-cancer KW - morphogenetic protein KW - osteoprogenitor cells KW - endochondral ossification KW - mouse model KW - trabecular bone KW - calcium phosphate KW - skeletal metastases Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117466 VL - 7 IS - 2 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - A TKA insert with a lateral flat articular surface maximizes external and internal tibial orientations without anterior lift-off relative to low- and ultracongruent surfaces JF - Journal of Personalized Medicine N2 - Background: In total knee arthroplasty (TKA), inserts can have different levels of medial and lateral congruency determined by the acuteness of the upslopes of the anterior and posterior articular surfaces. The present study evaluated an insert with different levels of lateral congruency and a medial ball-in-socket congruency to test the hypothesis that a lateral flat (F) insert maximizes external tibial orientation at extension and internal orientation at 90° flexion and lowers the incidence of anterior lift-off relative to low-congruent (LC) and ultracongruent (UC) lateral inserts. Methods: Two surgeons treated 23 patients with unrestricted caliper-verified kinematic alignment (KA) and posterior cruciate ligament (PCL) retention. They randomly trialed inserts with a medial radial dial that functioned as a built-in goniometer by measuring the tibial orientation relative to a sagittal line on the femoral trial component. Anterior lift-off of the insert from the baseplate indicated PCL tightness. Results: The F insert’s mean of 9° of external tibial orientation was higher than that of the LC (5°, p < 0.0001) and UC inserts (2°, p < 0.0001). The −13° of internal tibial orientation at 90° flexion was higher than that of the LC (−9°, p < 0.0001) and UC inserts (−7°, p < 0.0001). The 0% incidence of anterior lift-off was less than that of the LC (26%) and UC inserts (57%) (p < 0.0001). Conclusions: Surgeons and implant manufacturers should know that adding congruency to the lateral articular surface limits external tibial orientation in extension and internal tibial orientation at 90° flexion and overtightens the PCL. These rotational limitations and flexion space tightness can adversely affect patellofemoral tracking and knee flexion. KW - total knee arthroplasty KW - kinematic alignment KW - implant design KW - PCL retention KW - congruency Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286142 SN - 2075-4426 VL - 12 IS - 8 ER - TY - THES A1 - Roller, Christian T1 - Abriebverhalten der Harris-Galante-Pfanne in Kombination mit 28mm Keramik- und Metallköpfen T1 - Wear behavior of the Harris-Galante-Acetabular-Cup in Kombination with 28mm Ceramic- and Metal-Heads N2 - Obwohl Simulatoruntersuchungen geringere Abriebwerte für Keramik-Köpfe gezeigt haben, konnten klinische Studien diese Erkenntnisse bisher nicht bestätigen. Bisher existiert keine Studie mit einer angemessenen Teststärke, die das Abriebverhalten von 28 mm CoCr- und Biolox-Köpfen vergleicht. Ziel dieser Studie war es, das in-vivo-Abriebverhalten von Keramik- und Metall-Köpfen in Verbindung mit der Harris-Galante-Pfanne zu untersuchen. Bei allen Patienten wurde ein zementfreies Pfannenimplantat nach Harris-Galante (Zimmer) implantiert. Die Inlays bestanden aus konventionell gefertigtem UHMWPE. 108 Patienten erhielten CoCr-Köpfe, 99 weitere Patienten wurden mit Keramik-Köpfen (Biolox) versorgt. Die 2D-Abriebrate wurde mit der Hip-analysis-suite von Martell über einen Zeitraum von 5,2 Jahren bei den Biolox- beziehungsweise 8 Jahren bei den CoCr-Köpfen untersucht. Die Metall-Köpfe zeigten einen linearen Abrieb von 0,14  0,11 mm pro Jahr, verglichen mit 0,13  0,08 mm pro Jahr bei den Keramik-Köpfen. Dieser Unterschied war, insbesondere nach Anpassung an die klinischen Einflussfaktoren, nicht signifikant (p = 0,46). Die Power-Analyse zeigte eine Teststärke von 80%, einen Unterschied von 28% (0,038 mm pro Jahr) zu detektieren. Die vorliegende Studie ist die erste, die das Abriebverhalten von 28 mm Metall- und Keramik-Köpfen im gleichen Pfannenimplantat mit ausreichender Teststärke vergleicht. Mit einer Teststärke von 80%, eine Abriebreduktion um 28% zu erkennen, zeigt diese Studie keinen Unterschied zwischen Biolox- und Metall-Köpfen in Verbindung mit konventionellen UHMWPE-Inlays in einer modularen Pfanne. N2 - Although hip simulator testing shows decreased wear with alumina ceramic femoral heads, several clinical series have not supported this finding. To our knowledge, no published series exists with adequate power to compare 28 mm alumina vs. cobalt chrome wear rates. Our purpose is to compare the in-vivo clinical performance of alumina and cobalt chrome femoral bearings in the Harris-Galante-Acetabular -Cup. Patients underwent primary cementless hip replacement using the HGP-I and II acetabular components (Zimmer) with 28 mm bearings and conventional ultra high molecular weight polyethylene liners. 108 implants received cobalt-chrome bearings while 99 received alumina (Biolox) bearings. 2D linear wear rates were calculated using Hip-analysis-suite developed by Martell et al. The Biolox-heads were followed up for 5,2 years, the CoCR-heads were followed up for 8 years. The metal bearings demonstrated a mean linear wear rate of 0.14 mm/yr. +/- 0.11 mm/yr., compared to 0.13 mm/yr. +/- 0.08 mm/yr. for alumina. This difference was not significant after adjusting for covariates and using the non-parametric Mann-Whitney test (p= 0.46). Post-hoc power analysis indicated 80% power to detect a 0.038 mm/yr. (28%) difference in wear rates. This is the first study with adequate power to assess wear between 28 mm alumina and cobalt chrome femoral heads. With 80% power to detect a 28% wear reduction, our series shows no advantage in wear performance for alumina ceramics on conventional UHMWPE in a modular cup design. KW - Abrieb KW - Hüftgelenk KW - Harris-Galante KW - Osteolysen KW - Polyethylen KW - Wear KW - Hip KW - Harris-Galante KW - Oseolysis KW - Polyethelen Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-14197 ER -