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Dive into the research topics where Joerg Friesenbichler is active.

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Featured researches published by Joerg Friesenbichler.


International Journal of Cancer | 2014

The lymphocyte/monocyte ratio predicts poor clinical outcome and improves the predictive accuracy in patients with soft tissue sarcomas

Joanna Szkandera; Armin Gerger; Bernadette Liegl-Atzwanger; Gudrun Absenger; Michael Stotz; Joerg Friesenbichler; Slave Trajanoski; Tatjana Stojakovic; Katharina Eberhard; Andreas Leithner; Martin Pichler

Increasing evidence indicates the involvement of inflammation and coagulation in cancer progression and metastases. Inflammatory biomarkers hold great promise for improving the predictive ability of existing prognostic tools in cancer patients. In the present study, we investigated several inflammatory indices with regard to their prognostic relevance for predicting clinical outcome in soft tissue sarcoma (STS) patients. Three hundred and forty STS patients were divided into a training set (n = 170) and a validation set (n = 170). Besides well‐established clinico‐pathological prognostic factors, we evaluated the prognostic value of the neutrophil/lymphocyte (N/L) ratio, the lymphocyte/monocyte (L/M) ratio and the platelet/lymphocyte (P/L) ratio using Kaplan–Meier curves and univariate as well as multivariate Cox regression models. Additionally, we developed a nomogram by supplementing the L/M ratio to the well‐established Kattan nomogram and evaluated the predictive accuracy of this novel nomogram by applying calibration and Harrells concordance index (c‐index). In multivariate analysis, a low L/M ratio was significantly associated with decreased CSS and DFS (HR = 0.41, 95% CI = 0.18–0.97, p = 0.043; HR = 0.39, 95% CI = 0.16–0.91, p = 0.031, respectively) in the training set. Using the validation set for confirmation, we found also in multivariate analysis an independent value for CSS (HR = 0.33, 95% CI = 0.12–0.90, p = 0.03) and for DFS (HR = 0.36, 95% CI = 0.16–0.79, p = 0.01). The estimated c‐index was 0.74 using the original Kattan nomogram and 0.78 when the L/M ratio was added. Our study reports for the first time that the pre‐operative L/M ratio represents a novel independent prognostic factor for prediction the clinical outcome in STS patients. This easily determinable biomarker might be helpful in improved individual risk assessment.


Journal of the American Medical Informatics Association | 2010

Wikipedia and osteosarcoma: a trustworthy patients' information?

Andreas Leithner; Werner Maurer-Ertl; Mathias Glehr; Joerg Friesenbichler; Katharina Leithner; R. Windhager

The English version of the online encyclopedia, Wikipedia, has been recently reported to be the prominent source of online health information. However, there is little information concerning the quality of information found in Wikipedia. Therefore, we created a questionnaire asking for scope, completeness, and accuracy of information found on osteosarcoma. Three independent observers tested the English version of Wikipedia, as well as the patient version and the health professional version of the US National Cancer Institute (NCI) website. Answers were verified with authoritative resources and international guidelines. The results of our study demonstrate that the quality of osteosarcoma-related information found in the English Wikipedia is good but inferior to the patient information provided by the NCI. Therefore, non-peer-reviewed commonly used websites offering health information, such as Wikipedia, should include links to more definitive sources, such as those maintained by the NCI and professional international organizations on healthcare treatments. Furthermore, frequent checks should make sure such external links are to the highest quality and to the best-maintained aggregate sites on a given healthcare topic.


Orthopedics | 2011

Noninflammatory Pseudotumor Simulating Venous Thrombosis After Metal-on-Metal Hip Resurfacing

Werner Maurer-Ertl; Joerg Friesenbichler; Bernadette Liegl-Atzwanger; Gerda Kuerzl; Reinhard Windhager; Andreas Leithner

Metal-on-metal hip resurfacing has become a widespread procedure, especially in young, physically active patients. Pseudotumor is a new complication that can occur after hip resurfacing and metal-on-metal total hip arthroplasty (THA). This article presents a case of a 37-year-old woman who underwent metal-on-metal resurfacing of the left hip for symptomatic osteoarthritis. Twelve months following implantation, the patient reported painless swelling of the left lower leg. There was no clinical evidence of a deep venous thrombosis. Ultrasound and computed tomography showed a solid cystic lesion in the iliopsoas muscle, which communicated with the hip joint and compressed the external iliac vein. As a consequence, the cystic lesion was resected marginally. A few months later, the patient reported some discomfort in the groin and symptoms of instability, metallic clicking, and a restricted range of motion. Clinical and radiological examination revealed normal findings. Determining the serum concentration of cobalt and chromium revealed high increased levels of these metal ions. Ten months following excision of the pseudotumor, the patient reported recurrent swelling of the left lower leg. Computed tomography of the affected area showed a lobulated cystic formation; therefore, a relapse was suspected. At the second revision, the mass was excised and the implant was revised to a conventional ceramic-on-ceramic THA. At 30-month follow-up, the patient was doing well and there were no signs of local recurrence. Additionally, the metal ion levels of cobalt and chromium in the blood had significantly decreased.


International Orthopaedics | 2012

Serum metal ion levels after rotating-hinge knee arthroplasty: comparison between a standard device and a megaprosthesis.

Joerg Friesenbichler; Werner Maurer-Ertl; Patrick Sadoghi; Thomas Lovse; Reinhard Windhager; Andreas Leithner

PurposeThe effects of systemic metal ion exposure in patients with implants made of common prosthetic alloys continue to be a matter of concern. The aim of the study was to determine the measurement values of cobalt (Co), chromium (Cr) and molybdenum (Mo) in serum following rotating-hinge knee arthroplasty.MethodsBlood was taken from 25 patients [mean follow-up 35 (range nine to 67) months] treated with megaprostheses (n=17) or standard rotating-hinge devices (n=8) and analysed using electrothermal graphite furnace atomic absorption spectrometry (ET-ASS).ResultsDetermining the concentrations of metal ions following rotating-hinge knee arthroplasty revealed increments for Co and Cr but not Mo. Metal ion release was significantly higher in patients with megaprostheses compared to a standard rotating-hinge knee device (Co p=0,024; Cr p=0.025).ConclusionThe authors believe there might be an additional metal ion release from the surface of the prosthesis and not only from the articulating surfaces because, in cases of rotating-hinge knee prosthesis, there is a metal-on-polyethylene articulation and not a direct metal-on-metal junction. Nevertheless, long-term studies are required to determine adverse effects of Co, Cr and Mo following total hip replacement and total knee arthroplasty.


Zeitschrift für Naturforschung C | 2013

The influence of resveratrol on the synovial expression of matrix metalloproteinases and receptor activator of NF-kappaB ligand in rheumatoid arthritis fibroblast-like synoviocytes.

Mathias Glehr; Margherita Breisach; Sonja M. Walzer; Birgit Lohberger; Florentine Fürst; Joerg Friesenbichler; Beate Rinner; Alexander Avian; Reinhard Windhager; Andreas Leithner

Medication of rheumatoid arthritis (RA) remains challenging and often controversial concerning side effects or long-term complications. We investigated the effect of resveratrol, a phytoalexin discussed for its chondro-protective and anti-inflammatory qualities, on the synovial expression of matrix-degrading enzymes like matrix metalloproteinases (MMPs) and bone-remodelling proteins in RA fibroblast-like synoviocytes (FLS). Interleukin-1β- stimulated RA-FLS were treated with 100 μM resveratrol for 24 h. To evaluate the effect of resveratrol on the amount of bound/combined MMPs, a Luminex® xMAP multiplexing technology was used. The alteration in expression of receptor activator of nuclear factor- κB ligand (RANKL) and osteoprotegrin (OPG) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Resveratrol reduced the expression of MMP-1 (p = 0.022), MMP-3 (p = 0.021), and MMP-9 (p = 0.047). qRT-PCR showed a significant reduction in the relative abundance of the transcripts of OPG (p = 0.012) and RANKL (p = 0.018). Our in vitro findings indicate that resveratrol could be a new target for further pharmacological studies in the field of RA. In the future it could play a role as a possible substitute or supplement to currently used drugs against RA to prevent cartilage matrix degradation and pathological bone resorption due to inhibition of MMPs and RANKL


International Orthopaedics | 2012

Failure rate of a rotating hinge knee design due to yoke fracture of the hinged tibial insert: a retrospective data analysis and review of the literature

Joerg Friesenbichler; Ran Schwarzkopf; Patrick Sadoghi; Scott E. Marwin; Mathias Glehr; Werner Maurer-Ertl; Andreas Leithner

PurposeRotating hinge knee prostheses are known to provide inherent stability. Yoke fractures of the hinged tibial insert of modern generation rotating hinge devices are a matter of continued concern. The aim of this study was to describe incidence and management of yoke fracture of the LPS™ hinged tibial insert.MethodsRetrospective data analysis of two institutions identified 40 patients with a LPS™ total knee arthroplasty. Implant survival and prosthetic complications was calculated according to Kaplan-Meier.ResultsOut of the group of 40 patients, four fractures of the metal yoke occurred in four cases (failure rate: 10%). Furthermore, a second fracture occurred in two patients. The overall revision-free prosthetic survival was 57% at 38 months, while prosthetic survival until yoke fracture was 86% at 38 months.ConclusionHandling yoke fractures as mechanical complication includes replacing the hinged insert, stabilization of the joint and joint line height preservation in order to decrease the cantilever effect at the insert-base plate interface.


BMC Surgery | 2011

Auto-aggressive metallic mercury injection around the knee joint: a case report

Joerg Friesenbichler; Werner Maurer-Ertl; Patrick Sadoghi; Elisabeth Wolf; Andreas Leithner

BackgroundAccidental or intentional subcutaneous and/or intramuscular injection of metallic mercury is an uncommon form of poisoning. Although it does not carry the same risk as mercury vapour inhalation, it may cause destructive early and late reactions.Case PresentationHerein we present the case of a 29-year-old male patient who developed an obsessive-compulsive disorder causing auto-aggressive behaviour with injection of elemental mercury and several other foreign bodies into the soft tissues around the left knee about 15 years before initial presentation. For clinical examination X-rays and a CT-scan of the affected area were performed. Furthermore, blood was taken to determine the mercury concentration in the blood, which showed a concentration 17-fold higher than recommended. As a consequence, the mercury depots and several foreign bodies were resected marginally.ConclusionBlood levels of mercury will decrease rapidly following surgery, especially in combination with chelating therapy. In case of subcutaneous and intramuscular injection of metallic mercury we recommend marginal or wide excision of all contaminated tissue to prevent migration of mercury and chronic inflammation. Nevertheless, prolonged clinical and biochemical monitoring should be performed for several years to screen for chronic intoxication.


Scientific Reports | 2017

Clinical experience with the artificial bone graft substitute Calcibon used following curettage of benign and low-grade malignant bone tumors

Joerg Friesenbichler; Werner Maurer-Ertl; Marko Bergovec; Lukas A. Holzer; Kathrin Ogris; Lukas Leitner; Andreas Leithner

Artificial bone graft substitutes, such as Calcibon, are becoming increasingly interesting as they do not cause donor site morbidity which is an advantage compared to autologous bone grafts. The aim of this study was to evaluate the efficacy and potential complications associated with the use of Calcibon. Twenty-seven patients with benign and low-grade malignant bone tumors were treated with curettage and refilling of the bony cavity. Based on the radiological classification system of Neer, these lesions only comprised Grade I lesions, describing cysts that only require curettage and filling, but no additional treatment. At a mean follow up of six months we observed radiological consolidation without resorption of the bone graft substitute. These observations were also made at a mean follow-up of 13 and 32 months, respectively. According to the classification system of Goslings and Gouma we observed six surgical complications. Summing up, Calcibon seems to be a reliable bone graft substitute with low complication rates. However, delayed resorption should be expected. Calcibon seems to be an alternative to autologous bone grafts or allografts in adequate indications.


International Scholarly Research Notices | 2013

Evaluation of Stability of Rotating Hinge Knee Prostheses: A Biomechanical Study

Joerg Friesenbichler; Andreas Leithner; Mathias Glehr; Patrick Sadoghi; Werner Maurer-Ertl; Alexander Avian; Reinhard Windhager

Purpose. Rotating hinge knee prostheses should provide a stable situation following reconstruction. We performed a biomechanical analysis to establish the association between design of the central rotational stem (peg) and implants stability, in a theoretical setting. Methods. Six different rotating hinge designs were tested, and three observers performed two different measurements with a custom made biomechanical apparatus and laterally directed pressure. The aim was to assign the degree of tilting of the peg within the vertical post-in channel by extending the distraction as well as the maximum amount of distraction before the pegs dislocation. An intraclass-correlation coefficient (ICC) was calculated to determine the observers reliability. Results. Implant designs with cylindrical pegs of different lengths were superior to implant designs with conical or other shaped pegs concerning stability and maximum amount of distraction before dislocation, showing steep rising distraction-angular displacement curves. The ICC at 15 mm and 25 mm of distraction revealed high interobserver reliability (P < 0.001). Conclusion. The biomechanical analysis showed that rotating hinge prostheses with long and cylindrical pegs have the highest stability at any given amount of distraction. Designs with shorter and markedly tapered pegs may become unstable under conditions of mild joint distraction which has to be proven in future in vivo investigations.


Orthopedics | 2012

In vivo testing of knee stability after rotating-hinge total knee arthroplasty: a comparison of 2 knee systems.

Joerg Friesenbichler; Mathias Glehr; Patrick Sadoghi; Werner Maurer-Ertl; Florian Ott; Andreas Leithner

Rotating-hinge knee prostheses are used for reconstruction in cases of severe articular compromise and major bone loss. Biomechanical studies revealed that rotating-hinge designs with long and cylindrical pegs are more stable than devices with short and more tapered ones. Twenty-five patients underwent clinical examination using ultrasound, radiographs, and 3 different rating systems to examine the in vivo stability and functional outcome of 2 rotating-hinge knee systems. Overall, the study revealed that a stable reconstruction could be achieved with both tested devices, with good functional outcome. The results for medial and lateral lift-off during flexion and extension in ultrasonography were comparable, whereas the measured distraction of the Limb Preservation System (LPS/M.B.T.; DePuy, Warsaw, Indiana) was lower compared with the S-ROM Noiles prostheses (DePuy). The implant, the new formed capsule, and the remaining soft tissues have to maintain joint stability. Soft tissue reconstruction, especially the medial gastrocnemius flap, and the newly formed periprosthetic scar seems to prevent distraction of several millimeters. In addition, determining the lift-off with ultrasonography showed that the shape of the peg does not influence implants stability against lateral directed forces.

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Andreas Leithner

Medical University of Graz

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Patrick Sadoghi

Medical University of Graz

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Mathias Glehr

Medical University of Graz

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Reinhard Windhager

Medical University of Vienna

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Alexander Avian

Medical University of Graz

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Joanna Szkandera

Medical University of Graz

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Lukas A. Holzer

Medical University of Graz

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Armin Gerger

Medical University of Graz

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