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1.
Sci Total Environ ; 725: 138478, 2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32304968

ABSTRACT

An inexorable depletion of groundwater occurs where groundwater abstraction exceeds the natural recharge, a typical state of (semi-)arid regions, which calls for sustainable management of groundwater resources. This study aims to assess the available storage and recharge rates on a national scale in time and space by modelling the natural recharge in combination with a method to evaluate changing groundwater volumes, which revealed measures to quantify the overdraft of the observed national groundwater resources in Jordan. Applying the combination of hydrological model and method to evaluate changing groundwater volumes, a climate-driven systematic decline of groundwater recharge was eliminated as responsible process, while overdraft leads to dropping groundwater tables. The major findings are, the intensity of groundwater abstraction from a basin becomes visible through the fact, that simulated baseflow exceeds significantly the observed baseflow. About 75% of Jordan's groundwater basins are subject to intense groundwater depletion, reaching annual rates of up to 1 m in some basins. The most affected areas are the basins Zarka, Azraq and the predominantly fossil groundwater reservoirs in Southern Jordan. Contrasting the past, when variable annual precipitation patterns did not negatively influence groundwater recharge, simulations show significantly reduced annual groundwater recharge all over Jordan. Particularly affected is the agricultural backbone in the Jordan Mountains, where recharge rates are predicted to vary between -30 mm/yr and +10 mm/yr in the coming decades, being reflected in the disappearance of freshwater springs and ascending saltwater. The applied methodology is relevant and transferable to other data- and water scarce areas worldwide, allowing (i) a fast estimation of groundwater reservoir development on a national scale and (ii) an investigation of long-term effects of overdraft.

2.
Sci Total Environ ; 706: 136066, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31864136

ABSTRACT

The infiltration of untreated wastewater into aquifers highly endangers the availability of fresh-water for human consumption in semi-arid areas. This growing problem of potable water scarcity urgently requires solutions for groundwater protection. Decision support systems for local wastewater treatments in settlements already exist. However, the main challenge of implementing these for regional groundwater protection is to identify where wastewater treatments are most efficient for the whole region. In this paper, we addressed this scale-crossing problem with an interdisciplinary approach that combines regional risk assessment and assessment of local wastewater treatment scenarios. We analysed the impact of polluting the groundwater using vulnerability, hazard, and risk assessments. Thus, we identified the need for semi-arid and karst-related adjustments, defined more suitable standards for wastewater hazard values, and accounted for the groundwater dynamics beyond the vertical flow paths. Using a lateral groundwater flow model, we analysed the impact of the pollution sources and linked the regional and local scale successfully. Furthermore, we combined the geoscientific results with the urban water engineering methods of area and cost assessments for local wastewater scenarios. Based on the example of the Wadi al Arab aquifer in Jordan, we showed that implementing an adapted treatment solution in one of the heavily polluted suburban settlements could reduce 12% of the aquifer pollution, which affects 93% of the potential aquifer users. This novel method helps to identify settlements with significant pollution impact on the groundwater, as well as the users, and also gives specific guidelines to establish the most efficient locally tailored treatment solution.

3.
Arthroscopy ; 35(12): 3302-3303, 2019 12.
Article in English | MEDLINE | ID: mdl-31785762

ABSTRACT

Why does one patient achieve better results than another with nonoperative orthopaedic treatment? Aside from the specific underlying pathology of knee pain, there are demographic factors, including mental health, body mass index, tobacco use, and pain perception, that influence the clinical results and should be considered as part of the equation.


Subject(s)
Mental Health , Pain , Body Mass Index , Humans , Tobacco Use
4.
Clin J Sport Med ; 28(5): 485-489, 2018 09.
Article in English | MEDLINE | ID: mdl-29952840

ABSTRACT

OBJECTIVE: For elite athletes to train and compete at peak performance levels, it is necessary to manage their pain efficiently and effectively. A recent consensus meeting on the management of pain in elite athletes concluded that there are many gaps in the current knowledge and that further information and research is required. This article presents the crystallization of these acknowledged gaps in knowledge. DATA SOURCES: Information was gathered from a wide variety of published scientific sources that were reviewed at the consensus meeting and the gaps in knowledge identified. MAIN RESULTS: Gaps have been identified in the epidemiology of analgesic use, the management of pain associated with minor injuries, and the field of play management of pain for athletes with major injuries. From a pharmacological perspective, there is a lack of information on the prescribing of opioid medications in elite athletes and more data are required on the use of local anesthetics injections, corticosteroids, and nonsteroidal anti-inflammatory drugs during training and in competition. Pain management strategies for the general population are widely available, but there are few for the elite sporting population and virtually none for elite athletes with a disability. More research is also needed in assessing cognitive-behavior therapies in improving specific outcomes and also into the new process of psychologically informed physiotherapy. A key issue is the paucity of data relating to incidence or prevalence of persistent pain and how this relates to persistent dysfunction, exercise performance, and physiological function in later life. CONCLUSIONS: The identification of the gaps in knowledge in the management of pain in elite athletes will provide a unified direction for the retrieval of information and further research that will provide reassurance, speed return to active sport, and benefit performance.


Subject(s)
Athletes , Pain Management/methods , Pain/drug therapy , Pain/epidemiology , Analgesics/therapeutic use , Analgesics, Opioid/therapeutic use , Anesthetics/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Athletic Injuries/drug therapy , Athletic Performance , Humans , Injections , Sports
5.
Z Orthop Unfall ; 156(3): 324-329, 2018 06.
Article in German | MEDLINE | ID: mdl-29529695

ABSTRACT

A meniscal injury should not automatically lead to surgery. Even in light of all the developments in arthroscopic surgery, non-operative management still has a place in the treatment algorithms for lesions around the knee. In this second publication of the German guidelines for meniscal surgery, the authors describe the various treatment possibilities, their indications and offer critical insight into the various therapeutic options. This will allow the patient and physician alike to make the proper individual decisions. Various German speaking associations addressing topics surrounding the knee have joined forces to develop these guidelines for meniscal lesions. The hope is that these two publications on the topic will shed light on the ongoing debate and offer some guidance.


Subject(s)
Decision Support Techniques , Guideline Adherence , Menisci, Tibial/surgery , Arthroscopy/methods , Combined Modality Therapy , Conservative Treatment/methods , Germany , Humans , Prognosis
6.
Br J Sports Med ; 51(17): 1245-1258, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28827314

ABSTRACT

Pain is a common problem among elite athletes and is frequently associated with sport injury. Both pain and injury interfere with the performance of elite athletes. There are currently no evidence-based or consensus-based guidelines for the management of pain in elite athletes. Typically, pain management consists of the provision of analgesics, rest and physical therapy. More appropriately, a treatment strategy should address all contributors to pain including underlying pathophysiology, biomechanical abnormalities and psychosocial issues, and should employ therapies providing optimal benefit and minimal harm. To advance the development of a more standardised, evidence-informed approach to pain management in elite athletes, an IOC Consensus Group critically evaluated the current state of the science and practice of pain management in sport and prepared recommendations for a more unified approach to this important topic.


Subject(s)
Athletic Injuries/therapy , Pain Management/methods , Pain Management/standards , Sports Medicine/standards , Analgesics/standards , Analgesics/therapeutic use , Athletes , Consensus , Humans , Organizations , Practice Guidelines as Topic , Return to Sport
7.
Sci Total Environ ; 544: 1045-58, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26779955

ABSTRACT

The Dead Sea region has faced substantial environmental challenges in recent decades, including water resource scarcity, ~1m annual decreases in the water level, sinkhole development, ascending-brine freshwater pollution, and seismic disturbance risks. Natural processes are significantly affected by human interference as well as by climate change and tectonic developments over the long term. To get a deep understanding of processes and their interactions, innovative scientific approaches that integrate disciplinary research and education are required. The research project DESERVE (Helmholtz Virtual Institute Dead Sea Research Venue) addresses these challenges in an interdisciplinary approach that includes geophysics, hydrology, and meteorology. The project is implemented by a consortium of scientific institutions in neighboring countries of the Dead Sea (Israel, Jordan, Palestine Territories) and participating German Helmholtz Centres (KIT, GFZ, UFZ). A new monitoring network of meteorological, hydrological, and seismic/geodynamic stations has been established, and extensive field research and numerical simulations have been undertaken. For the first time, innovative measurement and modeling techniques have been applied to the extreme conditions of the Dead Sea and its surroundings. The preliminary results show the potential of these methods. First time ever performed eddy covariance measurements give insight into the governing factors of Dead Sea evaporation. High-resolution bathymetric investigations reveal a strong correlation between submarine springs and neo-tectonic patterns. Based on detailed studies of stratigraphy and borehole information, the extension of the subsurface drainage basin of the Dead Sea is now reliably estimated. Originality has been achieved in monitoring flash floods in an arid basin at its outlet and simultaneously in tributaries, supplemented by spatio-temporal rainfall data. Low-altitude, high resolution photogrammetry, allied to satellite image analysis and to geophysical surveys (e.g. shear-wave reflections) has enabled a more detailed characterization of sinkhole morphology and temporal development and the possible subsurface controls thereon. All the above listed efforts and scientific results take place with the interdisciplinary education of young scientists. They are invited to attend joint thematic workshops and winter schools as well as to participate in field experiments.

8.
FEMS Microbiol Ecol ; 90(3): 956-69, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25348393

ABSTRACT

Abundant microbial mats, recently discovered in underwater freshwater springs in the hypersaline Dead Sea, are mostly dominated by sulfur-oxidizing bacteria. We investigated the source of sulfide and the activity of these communities. Isotopic analysis of sulfide and sulfate in the spring water showed a fractionation of 39-50‰ indicative of active sulfate reduction. Sulfate reduction rates (SRR) in the spring sediment (< 2.8 nmol cm(-3) day(-1)) are too low to account for the measured sulfide flux. Thus, sulfide from the springs, locally reduced salinity and O2 from the Dead Sea water are responsible for the abundant microbial biomass around the springs. The springs flow is highly variable and accordingly the local salinities. We speculate that the development of microbial mats dominated by either Sulfurimonas/Sulfurovum-like or Thiobacillus/Acidithiobacillus-like sulfide-oxidizing bacteria, results from different mean salinities in the microenvironment of the mats. SRR of up to 10 nmol cm(-3) day(-1) detected in the Dead Sea sediment are surprisingly higher than in the less saline springs. While this shows the presence of an extremely halophilic sulfate-reducing bacteria community in the Dead Sea sediments, it also suggests that extensive salinity fluctuations limit these communities in the springs due to increased energetic demands for osmoregulation.


Subject(s)
Fresh Water/microbiology , Natural Springs/microbiology , Salinity , Seawater/microbiology , Sulfates/metabolism , Sulfides/metabolism , Archaea/metabolism , Bacteria/metabolism , Biomass , Epsilonproteobacteria , Geologic Sediments/microbiology , Oxidation-Reduction
9.
Sci Total Environ ; 485-486: 828-841, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24767316

ABSTRACT

The overall aim of the this study, which was conducted within the framework of the multilateral IWRM project SUMAR, was to expand the scientific basement to quantify surface- and groundwater fluxes towards the hypersaline Dead Sea. The flux significance for the arid vicinity around the Dead Sea is decisive not only for a sustainable management in terms of water availability for future generations but also for the resilience of the unique ecosystems along its coast. Coping with different challenges interdisciplinary methods like (i) hydrogeochemical fingerprinting, (ii) satellite and airborne-based thermal remote sensing, (iii) direct measurement with gauging station in ephemeral wadis and a first multilateral gauging station at the river Jordan, (iv) hydro-bio-geochemical approach at submarine and shore springs along the Dead Sea and (v) hydro(geo)logical modelling contributed to the overall aim. As primary results, we deduce that the following: (i) Within the drainage basins of the Dead Sea, the total mean annual precipitation amounts to 300 mm a(−1) west and to 179 mm a(−1) east of the lake, respectively. (ii) The total mean annual runoff volumes from side wadis (except the Jordan River) entering the Dead Sea is approximately 58­66 × 10(6) m(3) a(−1) (western wadis: 7­15 × 10(6) m(3) a(−1); eastern wadis: 51 × 10(6) m(3) a(−1)). (iii) The modelled groundwater discharge from the upper Cretaceous aquifers in both flanks of the Dead Sea towards the lake amounts to 177 × 10(6) m(3) a(−1). (iv) An unexpected abundance of life in submarine springs exists, which in turn explains microbial moderated geo-bio-chemical processes in the Dead Sea sediments, affecting the highly variable chemical composition of on- and offshore spring waters.The results of this work show a promising enhancement of describing and modelling the Dead Sea basin as a whole.


Subject(s)
Environmental Monitoring/methods , Fresh Water/chemistry , Groundwater/chemistry , Water Movements , Desert Climate , Fresh Water/analysis , Groundwater/analysis , Jordan
10.
Article in German | MEDLINE | ID: mdl-23633255

ABSTRACT

Animal data, that could show a correlation between anesthetic exposure and longterm damage to the developing brain, have raised concern within the international anesthesiology community, but also in patients, parents and media. The evaluation of the available literature does not provide evidence for changes in routine anesthetic practice associated with the order, to establish evidence through increased basic and clinical research about the mechanisms and possible effects in humans.


Subject(s)
Anesthetics/adverse effects , Brain Diseases/chemically induced , Brain Diseases/physiopathology , Brain/drug effects , Brain/physiopathology , Evidence-Based Medicine , Animals , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Risk Assessment
11.
Orthop Rev (Pavia) ; 4(3): e28, 2012 Sep 04.
Article in English | MEDLINE | ID: mdl-23066496

ABSTRACT

American football is one of the leading causes of athletic-related injuries. Injury rates in female elite players are mostly unknown. We hypothesized that the injury rates of female was comparable to those in men's football during practice, as well as games. From 2009 to 2011, injury data were collected from the German female national team during training camps, World Championship 2010 and International friendly matches. The injury was categorized by location on the body and recorded as fracture/dislocation, strain, concussion, contusion or other injury. Injury rates were determined based on the exposure of an athlete to a game or practice event. The injury rate was calculated as the ratio of injuries per 1000 athlete exposures (AE). The rate of injury was significantly higher during games (58.8/1000 AE) than practices [16.3/1000 AE, (P<0.01)]. Furthermore, the injury rate in the tryouts was significantly higher (24.05/1000 AE) compared to other training sessions with the national team (11.24/1000 AE). Our findings show that the injury rates in female elite American football players can be compared to those described for male players. Higher injury rates during matches than in training should also be underlined.

12.
PLoS One ; 7(6): e38319, 2012.
Article in English | MEDLINE | ID: mdl-22679498

ABSTRACT

Due to its extreme salinity and high Mg concentration the Dead Sea is characterized by a very low density of cells most of which are Archaea. We discovered several underwater fresh to brackish water springs in the Dead Sea harboring dense microbial communities. We provide the first characterization of these communities, discuss their possible origin, hydrochemical environment, energetic resources and the putative biogeochemical pathways they are mediating. Pyrosequencing of the 16S rRNA gene and community fingerprinting methods showed that the spring community originates from the Dead Sea sediments and not from the aquifer. Furthermore, it suggested that there is a dense Archaeal community in the shoreline pore water of the lake. Sequences of bacterial sulfate reducers, nitrifiers iron oxidizers and iron reducers were identified as well. Analysis of white and green biofilms suggested that sulfide oxidation through chemolitotrophy and phototrophy is highly significant. Hyperspectral analysis showed a tight association between abundant green sulfur bacteria and cyanobacteria in the green biofilms. Together, our findings show that the Dead Sea floor harbors diverse microbial communities, part of which is not known from other hypersaline environments. Analysis of the water's chemistry shows evidence of microbial activity along the path and suggests that the springs supply nitrogen, phosphorus and organic matter to the microbial communities in the Dead Sea. The underwater springs are a newly recognized water source for the Dead Sea. Their input of microorganisms and nutrients needs to be considered in the assessment of possible impact of dilution events of the lake surface waters, such as those that will occur in the future due to the intended establishment of the Red Sea-Dead Sea water conduit.


Subject(s)
Fresh Water/microbiology , Seawater/microbiology , Archaea/genetics , Archaea/isolation & purification , Biofilms/growth & development , Chlorobi/genetics , Chlorobi/isolation & purification , Cyanobacteria/genetics , Cyanobacteria/isolation & purification , RNA, Ribosomal, 16S/genetics , Water Microbiology
13.
Med Monatsschr Pharm ; 32(2): 57-62, 2009 Feb.
Article in German | MEDLINE | ID: mdl-19263913

ABSTRACT

Reports regarding sport injuries frequently pertain to the knee. Although ligament and meniscus damage are the most common, cartilage injuries are of great interest. Even with the great variety of treatment modalities available, the healing of these cartilage injuries remains problematic. Due to the complex structure of hyaline cartilage joint surface, repair has proven to be very difficult. The conservative treatment options range from orthotic devices and physical therapy to systemic and intraarticular medication. In case of failure, a wide variety of surgical interventions exist. Among these surgical treatment forms, one must differentiate between the repair and the reconstruction of hyaline joint surfaces. In the latter group only the osteochondral autologous transplantation procedures allow for the reconstruction of a cartilaginous lesion with hyaline cartilage as part of a single procedure. This paper will provide an overview of most common therapeutic approaches to cartilage injuries available today. Even with the ongoing discussions with regard to cartilage healing, the basics such as the ligamentous stability of the affected joint, the mechanical axis of the extremity and good neuromuscular control must always be part of the algorithm.


Subject(s)
Algorithms , Cartilage/injuries , Wounds and Injuries/therapy , Humans , Knee Injuries/surgery , Knee Injuries/therapy , Plastic Surgery Procedures , Wounds and Injuries/surgery
14.
Acta Orthop ; 79(2): 235-43, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18484250

ABSTRACT

BACKGROUND AND PURPOSE: Symptomatic treatment of osteoarthritis of the knee with leeches is presently undergoing a renaissance. Previous studies have shown methodical weaknesses. In the present study patients were blinded regarding the treatment, and a control group was included to explore possible differences in various subjective clinical scores and intake of pain medication over time between leech therapy and placebo control. PATIENTS AND METHODS: 113 patients with advanced osteoarthritis of the knee were included. The patients were randomized to a single treatment group, group I (single leech application, n = 38), a double treatment group, group II (double application, n = 35), and a control group (n = 40). The second treatment in group II took place after an interval of 4 weeks. The treatment in the control group was simulated with the help of an "artificial leech". Results were documented with the KOOS and WOMAC scores and also a visual analog scale (VAS) for pain. Changes in the use of pain medication were monitored over 26 weeks. RESULTS: An improvement in KOOS and WOMAC scores, and also in VAS, was found in all 3 groups following treatment. These improvements were statistically significant for treatment groups I and II during the complete follow-up period. The reduction in individual requirements for pain medication was also statistically significant. The greatest improvement was seen in the group treated twice with the leeches, with a long-term reduction of joint stiffness and improved function in the activities of daily living. INTERPRETATION: Leech therapy can reduce symptoms caused by osteoarthritis. Repeated use of the leeches appears to improve the long-term results. We have not determined whether the positive outcome of the leech therapy is caused by active substances released during the leeching, the placebo effect, or the high expectations placed on this unusual treatment form.


Subject(s)
Leeching , Osteoarthritis, Knee/therapy , Aged , Female , Follow-Up Studies , Humans , Leeching/adverse effects , Leeching/methods , Male , Middle Aged , Treatment Outcome
15.
Arch Orthop Trauma Surg ; 128(9): 1007-11, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18389265

ABSTRACT

INTRODUCTION: Autologous bone graft is the golden standard for bone grafting, but little is known about the influence of various preservation techniques used during surgery immediately following harvest on the osseous structures and graft vitality. Several studies focussed on the optimal treatment of the bone during harvest and implantation, but only few examined the intraoperative storage conditions on the back table. The aim of our study was to examine the influence of various intraoperative preservation techniques on human cancellous bone at different points to optimize the storage during surgery. MATERIALS AND METHODS: Cancellous bone was harvested during hip arthroplasty and stored for 2 and 4 h under dry conditions, inside a swab moistened with saline solution or in saline solution, 5% glucose solution or culture medium. After the storage period, the bone was cultured and examined 7 days after the first cells grew out in one of these groups. Following the identification of the cells as osteoblast-like cells, the cultures were analysed by fluorescence staining, cell count and the XTT-test. RESULTS: Fluorescence staining revealed no avital cells in all groups. Dry storage of the bone led to significantly lower cell metabolism after 2 h compared to saline solution and 5% glucose solution. The same was true after 4 h dry storage compared to the moistened swab, and glucose and culture medium. Cell count was significantly lower after 2 h of dry storage compared to saline solution and culture medium. CONCLUSIONS: Perioperative storage of cancellous bone under dry conditions should be avoided. The bone graft should be stored in saline or 5% glucose solution or a moistened swab.


Subject(s)
Femur/transplantation , Perioperative Care , Specimen Handling/methods , Aged , Cell Count , Cells, Cultured , Culture Media , Female , Femur/cytology , Fluorescence , Glucose , Humans , Male , Middle Aged , Sodium Chloride , Staining and Labeling , Transplantation, Autologous
16.
Arch Orthop Trauma Surg ; 128(12): 1461-6, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18330583

ABSTRACT

INTRODUCTION: Autologous bone graft is the gold standard for the filling of large osseous defects. Because of its limited supply and complications such as pain, bleeding or infection, the development of alternative bone substitutes has been the subject of several studies. In clinical practice, the most commonly used bone substitutes are calcium phosphates like hydroxyapatite or tricalcium phosphate. With the aim to improve the osseointegration of these materials, growth factors such as bone morphogenetic protein-2 (BMP-2) have been added. Preferably, an injectable bone substitute should be made available. Hyaluronic acid is a component of the extracellular matrix of many tissues, including bone. We examined the bone regenerative effect of commercially available, injectable hyaluronic acid (Hyalart) with and without addition of bone morphogenetic protein-2 (BMP-2). MATERIALS AND METHODS: Trepanation defects of 9.4 mm diameter in the intercondylar groove of sheep femora were filled with pure and augmented (200 microg BMP-2) hyaluronic acid. As controls, empty defects and defects treated with autologous bone graft harvested from the contralateral side were used. After 3 months, the defects were analysed by fluorescence microscopy after intravital fluorescence staining, contact microradiography, histology and histomorphometry. RESULTS: Treatment of the defects with loaded and unloaded hyaluronic acid resulted in a significant lack of bone formation inside the defects. Untreated defects showed an amount of 5.1% newly formed bone, and defects treated with autologous bone graft revealed a bone content of 20%. The difference between both groups was statistically significant (P < 0.05). Furthermore, there was neither a remarkable effect in the periphery of the defects nor ectopic bone formation. CONCLUSION: The application of the used injectable hyaluronic acid (Hyalart) with and without BMP-2 is not advantageous as sole bone substitute for the filling of osseous defects.


Subject(s)
Bone Morphogenetic Protein 2/pharmacology , Bone Regeneration/drug effects , Bone Substitutes/pharmacology , Hyaluronic Acid/pharmacology , Osteogenesis/drug effects , Animals , Bone Cysts/therapy , Bone Neoplasms/therapy , Bone Transplantation/methods , Disease Models, Animal , Femur , Injections, Intralesional , Osteogenesis/physiology , Probability , Random Allocation , Reference Values , Risk Factors , Sheep , Transplantation, Autologous , Treatment Failure
17.
J Biomater Appl ; 22(6): 559-76, 2008 May.
Article in English | MEDLINE | ID: mdl-18194994

ABSTRACT

Bone morphogenetic protein-2 (BMP-2) is a well-known osteoinductive protein, which requires a carrier for local application. As an alternative to the previously described carriers, an in situ hardening, resorbable, and osteoconductive beta-tricalcium phosphate cement (TCP) is tested. Trepanation defects in the bovine distal femoral epiphysis are filled with a composite consisting of TCP and 200 microg rhBMP-2 per cm3 TCP, autologous bone graft, pure TCP, or left empty. A radiological follow-up is performed after 7 weeks and 3 months. The sheep are euthanized and bone samples are analyzed by microradiography, histology, and histomorphometry. Microradiography and histology show similar results for pure TCP and the composite. The defects are filled with trabecular bone and newly formed bone is in close contact with the remaining TCP-particles. The majority of the cement is resorbed, in the composite group the amount of remaining cement particles is reduced. Defects treated with autologous bone graft are filled completely, while untreated defects shows only a small amount of bone originating from the rim of the defect. Histomorphometry of the defects treated with pure TCP shows a significantly increased bone content in comparison to defects treated with the composite or autologous bone graft. Analysis of the remaining cement particles shows significantly less cement in the TCP/rhBMP-2 group in comparison to pure TCP. The sum of bone and cement content in the rhBMP-2 group shows amounts comparable to the calcified structures found following autologous bone grafting. The addition of rhBMP-2 to the TCP leads to faster remodeling of the defect comparable to autologous bone graft, while defects treated with pure TCP are not completely remodeled.


Subject(s)
Bone Cements , Bone Morphogenetic Proteins/pharmacology , Bone Remodeling/drug effects , Calcium Phosphates , Transforming Growth Factor beta/pharmacology , Animals , Bone Morphogenetic Protein 2 , Cattle , Humans , Male , Recombinant Proteins/pharmacology , Sheep
18.
Arch Orthop Trauma Surg ; 128(7): 701-7, 2008 Jul.
Article in English | MEDLINE | ID: mdl-17653560

ABSTRACT

INTRODUCTION: Even following the introduction of the "third generation" cementing technique, an improvement of the fixation of the acetabular component similar to that of the femoral has not been shown in clinical studies. The goal of the present study was to achieve a better stability with the use of an amphiphilic bonder while preserving the mechanically important subchondral sclerosis. MATERIALS AND METHODS: In a total of 20 sheep, a cemented total hip replacement was implanted. In the treatment group (n = 10), the implantation was carried out following surface conditioning of the acetabular bed with an amphiphilic bonder. All the sheep were followed for 9 months. To assess the biocompatibility, the osseous ingrowth at the cement-bone interface was depicted with the help of an in vivo fluorescent marking of the osteoblasts. Additionally, conventional radiographs were obtained over the course of treatment. Finally, the ovine pelvic regions were split following a standardized technique allowing for histological evaluation of the cement-bone interfaces. RESULTS: The acetabular components of the treatment group revealed a stable cement-bone compound. In the control group, the implants were easily dislodged from their beds. This finding was consistent with the radiological and histological results, which had revealed increased, progressive lytic radiolucent lines and the interposition of fibrous tissue at the cement-bone interface in the control group compared to the treatment group. The bonder was biocompatible. CONCLUSION: Following the application of the bonder, the cemented acetabular components revealed an improved stability without signs of inflammation or neoplasia in a viable acetabular osseous bed. With the help of this technique, the in vivo longevities of cemented acetabular components can be increased in the clinical setting without sacrificing the biomechanical relevant subchondral sclerosis.


Subject(s)
Acetabulum/surgery , Arthroplasty, Replacement, Hip/methods , Hip Prosthesis , Joint Instability/prevention & control , Polymethyl Methacrylate/pharmacology , Acetabulum/pathology , Analysis of Variance , Animals , Arthroplasty, Replacement, Hip/adverse effects , Cementation/methods , Disease Models, Animal , Female , Immunohistochemistry , Joint Instability/diagnostic imaging , Osteogenesis , Polymethyl Methacrylate/chemistry , Probability , Prosthesis Design , Prosthesis Implantation , Radiography , Random Allocation , Reference Values , Risk Factors , Sensitivity and Specificity , Sheep, Domestic
19.
J Biomed Mater Res B Appl Biomater ; 85(1): 87-92, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17696156

ABSTRACT

Basic fibroblast growth factor is a well known osteostimulative protein. The effects of basic fibroblast growth factor are dose-dependent and, when used with a carrier, influenced by the release kinetics. Aim of our study was to determine the effects of a composite of basic fibroblast growth factor and a newly developed, in situ setting tricalcium phosphate (TCP) cement. A trepanation defect in the distal femoral epiphysis of Merino-Mix sheep with a diameter of 9.4 mm and 10 mm depth was filled with the in situ setting TCP cement combined with 0 or 200 microg of bFGF/cm(3) TCP, autologous bone graft or left empty. The sheep were euthanized after 3 months. The defect and the periimplant area were examined by microradiography, histology, and histomorphometry. The data was analyzed with the help of the Wilcoxon and Kruskal-Wallis tests. Defects filled with TCP with or without bFGF showed a close bone-cement contact. The histomorphometric analysis revealed that the addition of bFGF inhibited the ingrowth of bone significantly, while the resorption of the cement was not influenced. In conclusion, the clinical application of this bFGF/TCP-composite does not seem promising. The reason for the inhibition of new bone formation will be discussed, but requires further investigation.


Subject(s)
Biocompatible Materials , Bone Cements , Calcium Phosphates , Fibroblast Growth Factor 2 , Osteogenesis/physiology , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/metabolism , Bone Cements/chemistry , Bone Cements/metabolism , Calcium Phosphates/chemistry , Calcium Phosphates/metabolism , Drug Carriers/chemistry , Drug Carriers/metabolism , Femur/cytology , Femur/pathology , Femur/physiology , Fibroblast Growth Factor 2/chemistry , Fibroblast Growth Factor 2/metabolism , Implants, Experimental , Male , Materials Testing , Rats , Sheep, Domestic
20.
Eur Spine J ; 15 Suppl 5: 604-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16474944

ABSTRACT

Epithelioid sarcoma is a rare and highly malignant soft tissue tumor that is commonly found in the extremities and rarely in the trunk area. This malignant tumor often mimics granuloma or nodular fasciitis, which causes a delay in establishing the diagnosis. This type of cancer has a high recurrence rate. Surgical treatment requires wide radical resection. The objective of this case report is to highlight the unique location of a rare neoplasm and to illustrate the relentless course of epithelioid sarcoma despite initial radical resection. A 14-year-old boy was admitted to our facility with a soft tissue mass on the right lower thoracic spine. The large tumor mass had deeply penetrated into the muscles, infiltrated the neuroforamen of T9-T10 level, and compressed the dural sac. Immunohistological study of the biopsy was highly consistent with an epithelioid sarcoma. Wide excision of the mass, laminectomy and spine fusion with instrumentation was performed. The patient received chemotherapy and irradiation. The first recurrence of the neoplasm was seen as a contralateral metastasis 21 months after the resection. On the last follow-up, 3 years postoperatively, the patient was in a good general condition. However, further progression of the sarcoma had to be recognized. Our case encompasses multiple features that represent negative prognostic factors. Initial wide excision of the neoplasm and adjuvant therapy including chemotherapy and irradiation seem to slow down the relentless course of epithelioid sarcoma in the trunk.


Subject(s)
Orthopedic Procedures , Sarcoma/diagnosis , Soft Tissue Neoplasms/diagnosis , Spinal Neoplasms/diagnosis , Thoracic Vertebrae , Adolescent , Biopsy , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Neoplasm Invasiveness , Neoplasm Recurrence, Local , Orthopedic Fixation Devices , Positron-Emission Tomography , Postoperative Period , Radiography, Thoracic , Sarcoma/surgery , Soft Tissue Neoplasms/surgery , Spinal Fusion , Spinal Neoplasms/surgery
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