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Dive into the research topics where Gerold Holzer is active.

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Featured researches published by Gerold Holzer.


Journal of Bone and Mineral Research | 2009

Hip fractures and the contribution of cortical versus trabecular bone to femoral neck strength.

Gerold Holzer; Gobert von Skrbensky; Lukas A. Holzer; Wolfgang Pichl

Osteoporotic fractures are caused by both cortical thinning and trabecular bone loss. Both are seen to be important for bone fragility. The relative contributions of cortical versus trabecular bone have not been established. The aim of this study was to test the contribution of cortical versus trabecular bone to femoral neck stability in bone strength. In one femur from each pair of 18 human cadaver femurs (5 female; 4 male), trabecular bone was completely removed from the femoral neck, providing one bone with intact and the other without any trabecular structure in the femoral neck. Geometrical, X‐ray, and DXA measurements were carried out before biomechanical testing (forces to fracture). Femoral necks were osteotomized, slices were analyzed for cross‐sectional area (CSA) and cross‐sectional moment of inertia (CSMI), and results were compared with biomechanical testing data. Differences between forces needed to fracture excavated and intact femurs (ΔF/F mean) was 7.0% on the average (range, 4.6–17.3%). CSA of removed spongiosa did not correlate with difference of fracture load (ΔF/F mean), nor did BMD. The relative contribution of trabecular versus cortical bone in respect to bone strength in the femoral neck seems to be marginal and seems to explain the subordinate role of trabecular bone and its changes in fracture risk and the effects of treatment options in preventing fractures.


Clinical Orthopaedics and Related Research | 1999

Parathyroid hormone enhances fracture healing : A preliminary report

Gerold Holzer; Mark Walden Lundy; James Richard Hartke; Thomas A. Einhorn

This investigation tested the hypothesis that daily parenterally administered parathyroid hormone (1-34) improves fracture healing. Twenty, 3-month-old, male Sprague Dawley rats weighing approximately 400 g each, underwent the production of closed, unilateral mid-diaphyseal femoral fractures. Animals were divided into two groups of 10; the animals received either a daily subcutaneous injection of delivery vehicle (0.9% saline) or 80 micrograms/kg parathyroid hormone. On Day 21 after fracture the animals were euthanized, the femurs were removed and subjected to biomechanical testing, bone densitometry (dual energy x-ray absorptiometry, peripheral quantitative computed tomography), and histologic examination. Treatment with parathyroid hormone resulted in statistically significant increases in callus area and strength. Histologic examination of the calluses showed an increase in the amount of new bone formed. No differences were observed in the weights of the animals or the sizes of the bones. Values obtained using dual energy x-ray absorptiometry and peripheral quantitative computed tomography indicate an increase in density in the parathyroid hormone treated fractures consistent with the histologic appearance and the findings of increased strength, although these bone density changes did not achieve statistical significance. These results suggest that parenterally administered parathyroid hormone (1-34) may enhance or accelerate normal fracture healing and support the concept that this hormone be tested clinically as a systemic treatment for fractures that are slow to heal.


European Journal of Cancer | 2009

Prognostic factors and outcomes for osteosarcoma: an international collaboration

Emilios E. Pakos; Andreas D. Nearchou; Robert J. Grimer; Haris D. Koumoullis; Adesegun Abudu; Jos A.M. Bramer; L. Jeys; Alessandro Franchi; Guido Scoccianti; Domenico Andrea Campanacci; Rodolfo Capanna; Jorge Aparicio; Marie-Dominique Tabone; Gerold Holzer; Fashid Abdolvahab; Philipp T. Funovics; Martin Dominkus; Inci Ilhan; Su Gülsün Berrak; Ana Patiño-García; Luis Sierrasesúmaga; Mikel San-Julian; Moira Garraus; Antonio Sergio Petrilli; Reynaldo Jesus Garcia Filho; Carla Renata Pacheco Donato Macedo; Maria Teresa de Seixas Alves; Sven Seiwerth; Rajaram Nagarajan; Timothy P. Cripe

We aimed to evaluate the prognostic significance of traditional clinical predictors in osteosarcoma through an international collaboration of 10 teams of investigators (2680 patients) who participated. In multivariate models the mortality risk increased with older age, presence of metastatic disease at diagnosis, development of local recurrence when the patient was first seen, use of amputation instead of limb salvage/wide resection, employment of unusual treatments, use of chemotherapeutic regimens other than anthracycline and platinum and use of methotrexate. It was also influenced by the site of the tumour. The risk of metastasis increased when metastatic disease was present at the time the patient was first seen and also increased with use of amputation or unusual treatment combinations or chemotherapy regimens not including anthracycline and platinum. Local recurrence risk was higher in older patients, in those who had local recurrence when first seen and when no anthracycline and platinum were used in chemotherapy. Results were similar when limited to patients seen after 1990 and treated with surgery plus combination chemotherapy. This large-scale international collaboration identifies strong predictors of major clinical outcomes in osteosarcoma.


Journal of Arthroplasty | 2014

The 50 Highest Cited Papers in Hip and Knee Arthroplasty

Lukas A. Holzer; Gerold Holzer

The 50 highest cited articles related to hip and knee arthroplasty were searched in Thomson ISI Web of Science®. The 50 highest cited articles had up to 2495 citations. The top 10 papers according to absolute number were cited 580 times at least. Most papers were published in the Journal of Bone and Joint Surgery American Volume (n = 22). Eight countries contributed to the list with most contributions from the United States (n = 30). The majority of papers were published since 1990 (n = 27). Studies focusing on the clinical outcome of hip arthroplasty dominate the literature in orthopedic arthroplasty in respect to absolute citations numbers. In the last decade however, papers on perioperative management have been published that show a high citation frequency.


Acta Orthopaedica | 2013

Expression of VEGF, its receptors, and HIF-1α in Dupuytren’s disease

Lukas A. Holzer; Andrej Cör; Gerhard Pfandlsteiner; Gerold Holzer

Background and purpose — Dupuytren’s disease (DD) is a benign fibroproliferative process that affects the palmar fascia. The pathology of DD shows similarities with wound healing and tumor growth; hypoxia and angiogenesis play important roles in both. We investigated the role of angiogenic proteins in DD. Patients and methods — The expression of vascular endothelial growth factor (VEGF), its receptors vascular endothelial growth factor receptor 1 (VEGFR1) and vascular endothelial growth factor receptor 2 (VEGFR2), hypoxia-inducible factor alfa (HIF-1α), and alfa-smooth muscle actin (α-SMA) were analyzed immunohistochemically in fragments of excised Dupuytren’s tissue from 32 patients. We compared these values to values for expression in a control group. Results — 15 of 32 samples could be attributed to the involutional phase (α-SMA positive), whereas 17 samples were considered to be cords at the residual phase (α-SMA negative). In the involutional phase, the HIF-1α and VEGFR2 expression was statistically significantly higher than in the residual phase and in the controls. Interpretation — Both the VEGFR2 receptor and HIF-1α were expressed in α-SMA positive myofibroblast-rich nodules with characteristics of DD in the active involutional phase. Thus, hypoxia and (subsequently) angiogenesis may have a role in the pathophysiology of DD.


Archives of Osteoporosis | 2011

New considerations on the management of osteoporosis in Central and Eastern Europe (CEE): summary of the “3rd Summit on Osteoporosis—CEE”, November 2009, Budapest, Hungary

Peter L. Lakatos; A. Balogh; E. Czerwinski; Hans Peter Dimai; Didier Hans; Gerold Holzer; R. Lorenc; Vladimir Palicka; Barbara Obermayer-Pietsch; Jan J. Stepan; István Takács; Heinrich Resch; Eastern Europe (Cee)

IntroductionIn November 2009, the “3rd Summit on Osteoporosis—Central and Eastern Europe (CEE)” was held in Budapest, Hungary. The conference aimed to tackle issues regarding osteoporosis management in CEE identified during the second CEE summit in 2008 and to agree on approaches that allow most efficient and cost-effective diagnosis and therapy of osteoporosis in CEE countries in the future.DiscussionThe following topics were covered: past year experience from FRAX® implementation into local diagnostic algorithms; causes of secondary osteoporosis as a FRAX® risk factor; bone turnover markers to estimate bone loss, fracture risk, or monitor therapies; role of quantitative ultrasound in osteoporosis management; compliance and economical aspects of osteoporosis; and osteoporosis and genetics. Consensus and recommendations developed on these topics are summarised in the present progress report.ConclusionLectures on up-to-date data of topical interest, the distinct regional provenances of the participants, a special focus on practical aspects, intense mutual exchange of individual experiences, strong interest in cross-border cooperations, as well as the readiness to learn from each other considerably contributed to the establishment of these recommendations. The “4th Summit on Osteoporosis—CEE” held in Prague, Czech Republic, in December 2010 will reveal whether these recommendations prove of value when implemented in the clinical routine or whether further improvements are still required.


Journal of Osteoporosis | 2015

The Most Cited Papers in Osteoporosis and Related Research

Lukas A. Holzer; Andreas Leithner; Gerold Holzer

Osteoporosis is a systemic disease of the bone that affects millions of people and causes burden for both the affected individual and health systems and societies worldwide. Since the 1970s much research has been done in the field of osteoporosis. The number of citations of a paper reflects its influence and importance to the field. Thomson ISI Web of Science database was searched to retrieve a list of the fifty most cited articles related to osteoporosis and its research. The fifty most cited articles in absolute numbers in the field of osteoporosis were cited from 877 to 3056 times (mean 1141 ± 537). Most papers were published in the basic science category (n = 23). 395 authors contributed; a single paper had between one and 62 authors (mean: 10.02 ± 9.9 authors). 12 authors (3.04%) contributed between 7 and 4 papers; 340 authors (86.1%) were at least named once. Corresponding authors were from eight countries with most contributions from the United States (n = 34, 68%). The majority of papers were published in the 1990s (n = 29). The list of 50 most cited papers presents citation classics in the field of osteoporosis and related research.


Journal of Hand Surgery (European Volume) | 2013

Guillaume Dupuytren: His Life and Surgical Contributions

Lukas A. Holzer; Vincent de Parades; Gerold Holzer

Guillaume Dupuytren (1777-1835) was one of the most influential surgeons of the past. He described and popularized many conditions, including Dupuytren disease, which continues to carry his name. This article reviews Guillaume Dupuytrens life and his contributions in surgery.


Acta Ortopedica Brasileira | 2013

Analysis of scientific articles published in two general orthopaedic journals

Lukas A. Holzer; Gerold Holzer

OBJECTIVE: To give an overview of the behaviour and scientific contributions of the Journal of Bone and Joint Surgery American (JBJS-A) and British Volume (JBJS-B). METHODS: 480 original articles published in 2009 were identified through a combined comprehensive computer and manual library search. Articles were assigned to 11 orthopaedic categories and by country, type and specialty of the institution. Possible grants and citations were analysed. USA led all countries in published articles (36,87%), followed by UK (20,62%) and South Korea (5,83%). Most studies published were performed at academic institutions (65,83 %), only 4,16% at private practices. RESULTS: Almost half of the articles (46,24%) were published in three categories: hip (19.16%), knee (13.75%) and trauma (13.33%). In both journals 47.15% articles had at least one funding source. A review of articles published in major journals allows to show how research in orthopaedics is distributed worldwide. CONCLUSION: This study shows that a variety of different journals is neccessary to reflect the broad spectrum of orthopaedics in depth. Level of Evidence III, Retrospective Comparative Study.


Acta Medica Bulgarica | 2017

Patterns in the Diagnosis and Treatment of Osteoporosis in Men: A Questionnaire-based Survey in Central and Eastern European Countries

M. A. Boyanov; E. Czerwinski; A. Shinkov; V. Palička; Peter L. Lakatos; C. Poiana; Juraj Payer; Zdenko Killinger; T. Kocjan; Olga Lesnyak; Gerold Holzer; Heinrich Resch

Summary To assess the current practice patterns in the diagnosis and treatment of male osteoporosis based on questionnaires. Questionnaires were presented and filled out by osteoporosis experts from Austria, Bulgaria, the Czech Republic, Hungary, Poland, Romania, Slovakia, Slovenia and Russia. The questions included focused on the proportion of male referrals to DXA, the main reasons for referral, the preferred measurement sites and reference database, the definition of male osteoporosis, needed laboratory investigations, data on calcium and vitamin D supplementation as well as on treatment modalities and their reimbursement rate. Men comprised 5 to 10% of all DXA referrals. The main reasons for referral were low back pain and fractures. Most of the respondents used the International male reference database. The diagnosis of osteoporosis was based mainly on a T-score below −2.5 after the age of 50, but a few respondents added fractures as a necessary condition. Only 1/3 of men visiting DXA sites are expected to have normal BMD. A consensus for the use of laboratory investigations in male osteoporosis is practically lacking. Treatment modalities include alendronate, risedronate, zoledronate, denosumab, rhPTH and strontium (with some restrictions for the latter three). Data on treatment adherence and persistence are generally lacking except for Austria, Romania and Slovakia. The levels of reimbursement vary a lot across countries. Osteoporosis in men is an under-recognized problem in CEE countries, leading to a tremendous gap in the diagnosis and treatment.

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Lukas A. Holzer

Medical University of Vienna

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Gobert von Skrbensky

Medical University of Vienna

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Heinrich Resch

Medical University of Vienna

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Christoph Krall

Medical University of Vienna

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Gerhard M. Hobusch

Medical University of Vienna

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Andrej Cör

University of Primorska

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Juraj Payer

Comenius University in Bratislava

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Afrodite Zendeli

Medical University of Vienna

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