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Sample records for experimental orthopedic implants

  1. Porous metal for orthopedics implants

    OpenAIRE

    Matassi, Fabrizio; Botti, Alessandra; Sirleo, Luigi; Carulli, Christian; Innocenti, Massimo

    2013-01-01

    Porous metal has been introduced to obtain biological fixation and improve longevity of orthopedic implants. The new generation of porous metal has intriguing characteristics that allows bone healing and high osteointegration of the metallic implants. This article gives an overview about biomaterials properties of the contemporary class of highly porous metals and about the clinical use in orthopaedic surgery.

  2. New biomaterials for orthopedic implants

    Directory of Open Access Journals (Sweden)

    Ong KL

    2015-09-01

    Full Text Available Kevin L Ong, Brian Min Yun, Joshua B WhiteExponent, Inc., Philadelphia, PA, USAAbstract: With the increasing use of orthopedic implants worldwide, there continues to be great interest in the development of novel technologies to further improve the effective clinical performance of contemporary treatment modalities and devices. Continuing research interest also exists in developing novel bulk biomaterials (eg, polycarbonate urethanes, silicon or novel formulations of existing but less widely used biomaterials (eg, polyaryletherketones, polyetheretherketone. There is also growing focus on customizing the material properties of bioabsorbables and composite materials with fillers such as bioactive ceramics. In terms of tissue engineering, more recent developments have focused on basic engineering and biological fundamentals to use cells, signaling factors, and the scaffold material itself to better restore tissue and organ structure and function. There has also been recent controversy with the use of injectables as a nonsurgical approach to treat joint disorders, but more attention is being directed toward the development of newer formulations with different molecular weights. The industry has also continuously sought to improve coatings to supplement the function of existing implants, with the goal of improving their osseointegrative qualities and incorporating antimicrobial properties. These include the use of bone morphogenetic protein, bisphosphonates, calcium phosphate, silicon nitride, and iodine. Due to the widespread use of bone graft materials, recent developments in synthetic graft materials have explored further development of bioactive glass, ceramic materials, and porous titanium particles. This review article provides an overview of ongoing efforts in the above research areas.Keywords: coatings, scaffolds, bioabsorbables, bone graft, injectables

  3. Bioactive glass coatings for orthopedic metallic implants

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    Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki; Tomsia, Antoni P.

    2003-06-30

    The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.

  4. Power harvesting using PZT ceramics embedded in orthopedic implants.

    Science.gov (United States)

    Chen, Hong; Liu, Ming; Jia, Chen; Wang, Zihua

    2009-09-01

    Battery lifetime has been the stumbling block for many power-critical or maintenance-free real-time embedded applications, such as wireless sensors and orthopedic implants. Thus a piezoelectric material that could convert human motion into electrical energy provides a very attractive solution for clinical implants. In this work, we analyze the power generation characteristics of stiff lead zirconate titanate (PZT) ceramics and the equivalent circuit through extensive experiments. Our experimental framework allows us to explore many important design considerations of such a PZT-based power generator. Overall we can achieve a PZT element volume of 0.5 x 0.5 x 1.8 cm, which is considerably smaller than the results reported so far. Finally, we outline the application of our PZT elements in a total knee replacement (TKR) implant.

  5. Metallic artifact in MRI after removal of orthopedic implants

    International Nuclear Information System (INIS)

    Bagheri, Mohammad Hadi; Hosseini, Mehrdad Mohammad; Emami, Mohammad Jafar; Foroughi, Amin Aiboulhassani

    2012-01-01

    Objective: The aim of the present study was to evaluate the metallic artifacts in MRI of the orthopedic patients after removal of metallic implants. Subjects and methods: From March to August 2009, 40 orthopedic patients operated for removal of orthopedic metallic implants were studied by post-operative MRI from the site of removal of implants. A grading scale of 0–3 was assigned for artifact in MR images whereby 0 was considered no artifact; and I–III were considered mild, moderate, and severe metallic artifacts, respectively. These grading records were correlated with other variables including the type, size, number, and composition of metallic devices; and the site and duration of orthopedic devices stay in the body. Results: Metallic susceptibly artifacts were detected in MRI of 18 of 40 cases (45%). Screws and pins in removed hardware were the most important factors for causing artifacts in MRI. The artifacts were found more frequently in the patients who had more screws and pins in the removed implants. Gender, age, site of implantation of the device, length of the hardware, composition of the metallic implants (stainless steel versus titanium), and duration of implantation of the hardware exerted no effect in producing metallic artifacts after removal of implants. Short TE sequences of MRI (such as T1 weighted) showed fewer artifacts. Conclusion: Susceptibility of metallic artifacts is a frequent phenomenon in MRI of patients upon removal of metallic orthopedic implants.

  6. Metallic artifact in MRI after removal of orthopedic implants.

    Science.gov (United States)

    Bagheri, Mohammad Hadi; Hosseini, Mehrdad Mohammad; Emami, Mohammad Jafar; Foroughi, Amin Aiboulhassani

    2012-03-01

    The aim of the present study was to evaluate the metallic artifacts in MRI of the orthopedic patients after removal of metallic implants. From March to August 2009, 40 orthopedic patients operated for removal of orthopedic metallic implants were studied by post-operative MRI from the site of removal of implants. A grading scale of 0-3 was assigned for artifact in MR images whereby 0 was considered no artifact; and I-III were considered mild, moderate, and severe metallic artifacts, respectively. These grading records were correlated with other variables including the type, size, number, and composition of metallic devices; and the site and duration of orthopedic devices stay in the body. Metallic susceptibly artifacts were detected in MRI of 18 of 40 cases (45%). Screws and pins in removed hardware were the most important factors for causing artifacts in MRI. The artifacts were found more frequently in the patients who had more screws and pins in the removed implants. Gender, age, site of implantation of the device, length of the hardware, composition of the metallic implants (stainless steel versus titanium), and duration of implantation of the hardware exerted no effect in producing metallic artifacts after removal of implants. Short TE sequences of MRI (such as T1 weighted) showed fewer artifacts. Susceptibility of metallic artifacts is a frequent phenomenon in MRI of patients upon removal of metallic orthopedic implants. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Clinical potential of implantable wireless sensors for orthopedic treatments.

    Science.gov (United States)

    Karipott, Salil Sidharthan; Nelson, Bradley D; Guldberg, Robert E; Ong, Keat Ghee

    2018-04-01

    Implantable wireless sensors have been used for real-time monitoring of chemicals and physical conditions of bones, tendons and muscles to diagnose and study orthopedic diseases and injuries. Due to the importance of these sensors in orthopedic care, a critical review, which not only analyzes the underlying technologies but also their clinical implementations and challenges, will provide a landscape view on their current state and their future clinical role. Areas covered: By conducting an extensive literature search and following the leaders of orthopedic implantable wireless sensors, this review covers the battery-powered and battery-free wireless implantable sensor technologies, and describes their implementation for hips, knees, spine, and shoulder stress/strain monitoring. Their advantages, limitations, and clinical challenges are also described. Expert commentary: Currently, implantable wireless sensors are mostly limited for scientific investigations and demonstrative experiments. Although rapid advancement in sensors and wireless technologies will push the reliability and practicality of these sensors for clinical realization, regulatory constraints and financial viability in medical device industry may curtail their continuous adoption for clinical orthopedic applications. In the next five years, these sensors are expected to gain increased interest from researchers, but wide clinical adoption is still unlikely.

  8. Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein.

    Directory of Open Access Journals (Sweden)

    Andreas Baranowski

    Full Text Available Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES, and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants

  9. A touch probe method of operating an implantable RFID tag for orthopedic implant identification.

    Science.gov (United States)

    Liu, Xiaoyu; Berger, J Lee; Ogirala, Ajay; Mickle, Marlin H

    2013-06-01

    The major problem in operating an implantable radio-frequency identification (RFID) tag embedded on an orthopedic implant is low efficiency because of metallic interference. To improve the efficiency, this paper proposes a method of operating an implantable passive RFID tag using a touch probe at 13.56 MHz. This technology relies on the electric field interaction between two pairs of electrodes, one being a part of the touch probe placed on the surface of tissue and the other being a part of the tag installed under the tissue. Compared with using a conventional RFID antenna such as a loop antenna, this method has a better performance in the near field operation range to reduce interference with the orthopedic implant. Properly matching the touch probe and the tag to the tissue and the implant reduces signal attenuation and increases the overall system efficiency. The experiments have shown that this method has a great performance in the near field transcutaneous operation and can be used for orthopedic implant identification.

  10. Bacterial adherence to tantalum versus commonly used orthopedic metallic implant materials.

    Science.gov (United States)

    Schildhauer, Thomas A; Robie, Bruce; Muhr, Gert; Köller, Manfred

    2006-07-01

    Evaluation of bacterial adhesion to pure tantalum and tantalum-coated stainless steel versus commercially pure titanium, titanium alloy (Ti-6Al-4V), and grit-blasted and polished stainless steel. Experimental in vitro cell culture study using Staphylococcus aureus and Staphylococcus epidermidis to evaluate qualitatively and quantitatively bacterial adherence to metallic implants. A bacterial adhesion assay was performed by culturing S. aureus (ATCC 6538) and S. epidermidis (clinical isolate) for one hour with tantalum, tantalum-coated stainless steel, titanium, titanium alloy, grit-blasted and polished stainless steel metallic implant discs. Adhered living and dead bacteria were stained using a 2-color fluorescence assay. Adherence was then quantitatively evaluated by fluorescence microscopy and digital image processing. Qualitative adherence of the bacteria was analyzed with a scanning electron microscope. The quantitative data were related to the implant surface roughness (Pa-value) as measured by confocal laser scanning microscopy. Bacterial adherence of S. aureus varied significantly (p = 0.0035) with the type of metallic implant. Pure tantalum presented with significantly (p titanium alloy, polished stainless steel, and tantalum-coated stainless steel. Furthermore, pure tantalum had a lower, though not significantly, adhesion than commercially pure titanium and grit-blasted stainless steel. Additionally, there was a significantly higher S. aureus adherence to titanium alloy than to commercially pure titanium (p = 0.014). S. epidermidis adherence was not significantly different among the tested materials. There was no statistically significant correlation between bacterial adherence and surface roughness of the tested implants. Pure tantalum presents with a lower or similar S. aureus and S. epidermidis adhesion when compared with commonly used materials in orthopedic implants. Because bacterial adhesion is an important predisposing factor in the development of

  11. PEEK Biomaterials in Trauma, Orthopedic, and Spinal Implants

    Science.gov (United States)

    Kurtz, S. M.; Devine, J. N.

    2007-01-01

    Since the 1980s, polyaryletherketones (PAEKs) have been increasingly employed as biomaterials for trauma, orthopedic, and spinal implants. We have synthesized the extensive polymer science literature as it relates to structure, mechanical properties, and chemical resistance of PAEK biomaterials. With this foundation, one can more readily appreciate why this family of polymers will be inherently strong, inert, and biocompatible. Due to its relative inertness, PEEK biomaterials are an attractive platform upon which to develop novel bioactive materials, and some steps have already been taken in that direction, with the blending of HA and TCP into sintered PEEK. However, to date, blended HA-PEEK composites have involved a trade-off in mechanical properties in exchange for their increased bioactivity. PEEK has had the greatest clinical impact in the field of spine implant design, and PEEK is now broadly accepted as a radiolucent alternative to metallic biomaterials in the spine community. For mature fields, such as total joint replacements and fracture fixation implants, radiolucency is an attractive but not necessarily critical material feature. PMID:17686513

  12. Selective laser sintering of calcium phosphate materials for orthopedic implants

    Science.gov (United States)

    Lee, Goonhee

    control of micro and macro pore structure, to maximize bone healing and provide sufficient mechanical strength. It also permits the complete removal of the polymeric binders that are resided in the SLS process. In collaboration with the University of Texas Health Science Center at San Antonio and BioMedical Enterprises, Inc., porous implants based on anatomical geometry have been successfully implanted in rabbits and dogs. These histologic animal studies reveal excellent biocompatibility and show its great potential for commercial custom-fit implant manufacture. The second research effort involves fabrication of fully dense bone for application in dental restoration and load-bearing orthopedic functions. Calcium phosphate glass melts, proven to be biocompatible in the first effort, were cast into carbon molds. Processes were developed for preparing the molds. These carbon molds of anatomic shape can be prepared from either Computer Numerical Control (CNC) milling of slab stock or SLS processing of thermoset-coated graphite powder. The CNC milling method provides accurate dimension of the molds in a short period of time, however, the capable geometries are limited; generally two pieces of molds are required for complex shapes. The SLS method provides very complex shape green molds. However, they need to go through pyrolysis of thermoset binder to provide the high temperature capability reached at calcium phosphate melt temperatures (1100°C) and noticeable shrinkage was observed during pyrolysis. The cast glass was annealed to develop polycrystalline calcium phosphate. This process also exhibits great potential.

  13. In-vivo orthopedic implant diagnostic device for sensing load, wear, and infection

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    Evans, III, Boyd McCutchen; Thundat, Thomas G.; Komistek, Richard D.; Dennis, Douglas A.; Mahfouz, Mohamed

    2006-08-29

    A device for providing in vivo diagnostics of loads, wear, and infection in orthopedic implants having at least one load sensor associated with the implant, at least one temperature sensor associated with the implant, at least one vibration sensor associated with the implant, and at least one signal processing device operatively coupled with the sensors. The signal processing device is operable to receive the output signal from the sensors and transmit a signal corresponding with the output signal.

  14. Biological Strategies for Improved Osseointegration and Osteoinduction of Porous Metal Orthopedic Implants

    Science.gov (United States)

    Riester, Scott M.; Bonin, Carolina A.; Kremers, Hilal Maradit; Dudakovic, Amel; Kakar, Sanjeev; Cohen, Robert C.; Westendorf, Jennifer J.

    2015-01-01

    The biological interface between an orthopedic implant and the surrounding host tissue may have a dramatic effect upon clinical outcome. Desired effects include bony ingrowth (osseointegration), stimulation of osteogenesis (osteoinduction), increased vascularization, and improved mechanical stability. Implant loosening, fibrous encapsulation, corrosion, infection, and inflammation, as well as physical mismatch may have deleterious clinical effects. This is particularly true of implants used in the reconstruction of load-bearing synovial joints such as the knee, hip, and the shoulder. The surfaces of orthopedic implants have evolved from solid-smooth to roughened-coarse and most recently, to porous in an effort to create a three-dimensional architecture for bone apposition and osseointegration. Total joint surgeries are increasingly performed in younger individuals with a longer life expectancy, and therefore, the postimplantation lifespan of devices must increase commensurately. This review discusses advancements in biomaterials science and cell-based therapies that may further improve orthopedic success rates. We focus on material and biological properties of orthopedic implants fabricated from porous metal and highlight some relevant developments in stem-cell research. We posit that the ideal primary and revision orthopedic load-bearing metal implants are highly porous and may be chemically modified to induce stem cell growth and osteogenic differentiation, while minimizing inflammation and infection. We conclude that integration of new biological, chemical, and mechanical methods is likely to yield more effective strategies to control and modify the implant–bone interface and thereby improve long-term clinical outcomes. PMID:25348836

  15. PREPARATION AND CHARACTERIZATION OF Ti-Al-Nb ALLOYS FOR ORTHOPEDIC IMPLANTS

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    Oliveira V.

    1998-01-01

    Full Text Available Pure titanium shows very interesting characteristics such as high strength-to-weight ratio, very good corrosion resistance and excellent biocompatibility, which make this material appropriate for use in orthopedic and dental implants. Due to the mechanical properties of pure titanium, its use in implants is restricted to applications which involve moderate mechanical stress, such as dental implants. In applications where high mechanical strength is necessary, like orthopedic implants, it is appropriate to employ titanium-based alloys, which have better properties than pure titanium. The present work is related to the microstructure and corrosion resistance characterization of the Ti-6Al-7Nb alloy, designed to be used in orthopedic prostheses.

  16. Value and clinical application of orthopedic metal artifact reduction algorithm in CT scans after orthopedic metal implantation

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    Hu, Yi; Pan, Shinong; Zhao, Xudong; Guo, Wenli; He, Ming; Guo, Qiyong [Shengjing Hospital of China Medical University, Shenyang (China)

    2017-06-15

    To evaluate orthopedic metal artifact reduction algorithm (O-MAR) in CT orthopedic metal artifact reduction at different tube voltages, identify an appropriate low tube voltage for clinical practice, and investigate its clinical application. The institutional ethical committee approved all the animal procedures. A stainless-steel plate and four screws were implanted into the femurs of three Japanese white rabbits. Preoperative CT was performed at 120 kVp without O-MAR reconstruction, and postoperative CT was performed at 80–140 kVp with O-MAR. Muscular CT attenuation, artifact index (AI) and signal-to-noise ratio (SNR) were compared between preoperative and postoperative images (unpaired t test), between paired O-MAR and non-O-MAR images (paired Student t test) and among different kVp settings (repeated measures ANOVA). Artifacts' severity, muscular homogeneity, visibility of inter-muscular space and definition of bony structures were subjectively evaluated and compared (Wilcoxon rank-sum test). In the clinical study, 20 patients undertook CT scan at low kVp with O-MAR with informed consent. The diagnostic satisfaction of clinical images was subjectively assessed. Animal experiments showed that the use of O-MAR resulted in accurate CT attenuation, lower AI, better SNR, and higher subjective scores (p < 0.010) at all tube voltages. O-MAR images at 100 kVp had almost the same AI and SNR as non-O-MAR images at 140 kVp. All O-MAR images were scored ≥ 3. In addition, 95% of clinical CT images performed at 100 kVp were considered satisfactory. O-MAR can effectively reduce orthopedic metal artifacts at different tube voltages, and facilitates low-tube-voltage CT for patients with orthopedic metal implants.

  17. Value and clinical application of orthopedic metal artifact reduction algorithm in CT scans after orthopedic metal implantation

    International Nuclear Information System (INIS)

    Hu, Yi; Pan, Shinong; Zhao, Xudong; Guo, Wenli; He, Ming; Guo, Qiyong

    2017-01-01

    To evaluate orthopedic metal artifact reduction algorithm (O-MAR) in CT orthopedic metal artifact reduction at different tube voltages, identify an appropriate low tube voltage for clinical practice, and investigate its clinical application. The institutional ethical committee approved all the animal procedures. A stainless-steel plate and four screws were implanted into the femurs of three Japanese white rabbits. Preoperative CT was performed at 120 kVp without O-MAR reconstruction, and postoperative CT was performed at 80–140 kVp with O-MAR. Muscular CT attenuation, artifact index (AI) and signal-to-noise ratio (SNR) were compared between preoperative and postoperative images (unpaired t test), between paired O-MAR and non-O-MAR images (paired Student t test) and among different kVp settings (repeated measures ANOVA). Artifacts' severity, muscular homogeneity, visibility of inter-muscular space and definition of bony structures were subjectively evaluated and compared (Wilcoxon rank-sum test). In the clinical study, 20 patients undertook CT scan at low kVp with O-MAR with informed consent. The diagnostic satisfaction of clinical images was subjectively assessed. Animal experiments showed that the use of O-MAR resulted in accurate CT attenuation, lower AI, better SNR, and higher subjective scores (p < 0.010) at all tube voltages. O-MAR images at 100 kVp had almost the same AI and SNR as non-O-MAR images at 140 kVp. All O-MAR images were scored ≥ 3. In addition, 95% of clinical CT images performed at 100 kVp were considered satisfactory. O-MAR can effectively reduce orthopedic metal artifacts at different tube voltages, and facilitates low-tube-voltage CT for patients with orthopedic metal implants

  18. Metal artifact reduction image reconstruction algorithm for CT of implanted metal orthopedic devices: a work in progress

    International Nuclear Information System (INIS)

    Liu, Patrick T.; Pavlicek, William P.; Peter, Mary B.; Roberts, Catherine C.; Paden, Robert G.; Spangehl, Mark J.

    2009-01-01

    Despite recent advances in CT technology, metal orthopedic implants continue to cause significant artifacts on many CT exams, often obscuring diagnostic information. We performed this prospective study to evaluate the effectiveness of an experimental metal artifact reduction (MAR) image reconstruction program for CT. We examined image quality on CT exams performed in patients with hip arthroplasties as well as other types of implanted metal orthopedic devices. The exam raw data were reconstructed using two different methods, the standard filtered backprojection (FBP) program and the MAR program. Images were evaluated for quality of the metal-cement-bone interfaces, trabeculae ≤1 cm from the metal, trabeculae 5 cm apart from the metal, streak artifact, and overall soft tissue detail. The Wilcoxon Rank Sum test was used to compare the image scores from the large and small prostheses. Interobserver agreement was calculated. When all patients were grouped together, the MAR images showed mild to moderate improvement over the FBP images. However, when the cases were divided by implant size, the MAR images consistently received higher image quality scores than the FBP images for large metal implants (total hip prostheses). For small metal implants (screws, plates, staples), conversely, the MAR images received lower image quality scores than the FBP images due to blurring artifact. The difference of image scores for the large and small implants was significant (p=0.002). Interobserver agreement was found to be high for all measures of image quality (k>0.9). The experimental MAR reconstruction algorithm significantly improved CT image quality for patients with large metal implants. However, the MAR algorithm introduced blurring artifact that reduced image quality with small metal implants. (orig.)

  19. Development and Evaluation of Polyvinyl Alcohol-Hydrogels as an Artificial Atrticular Cartilage for Orthopedic Implants

    Directory of Open Access Journals (Sweden)

    Masanori Kobayashi

    2010-04-01

    Full Text Available Due to its excellent biocompatibility and mechanical properties, various different applications of polyvinyl alcohol-hydrogels (PVA-H has been attempted in many fields. In the field of orthopedic surgery, we have been engaged for long time in research on the clinical applications of PVA-H as a artificial cartilage, and have performed many basic experiments on the mechanical properties, synthesis of PVA-H, and developed orthopedic implants using PVA-H. From these studies, many applications of artificial articular cartilage, intervertbral disc and artificial meniscus etc. have been developed. This review will present the overview of the applications and recent advances of PVA-H cartilages, and discuss clinical potential of PVA-H for orthopedics implant.

  20. Development and Evaluation of Polyvinyl Alcohol-Hydrogels as an Artificial Atrticular Cartilage for Orthopedic Implants

    Science.gov (United States)

    Kobayashi, Masanori; Hyu, Hyon Suong

    2010-01-01

    Due to its excellent biocompatibility and mechanical properties, various different applications of polyvinyl alcohol-hydrogels (PVA-H) has been attempted in many fields. In the field of orthopedic surgery, we have been engaged for long time in research on the clinical applications of PVA-H as a artificial cartilage, and have performed many basic experiments on the mechanical properties, synthesis of PVA-H, and developed orthopedic implants using PVA-H. From these studies, many applications of artificial articular cartilage, intervertbral disc and artificial meniscus etc. have been developed. This review will present the overview of the applications and recent advances of PVA-H cartilages, and discuss clinical potential of PVA-H for orthopedics implant.

  1. Application of computer graphics in the design of custom orthopedic implants.

    Science.gov (United States)

    Bechtold, J E

    1986-10-01

    Implementation of newly developed computer modelling techniques and computer graphics displays and software have greatly aided the orthopedic design engineer and physician in creating a custom implant with good anatomic conformity in a short turnaround time. Further advances in computerized design and manufacturing will continue to simplify the development of custom prostheses and enlarge their niche in the joint replacement market.

  2. Readability of Patient Education Materials From the Web Sites of Orthopedic Implant Manufacturers.

    Science.gov (United States)

    Yi, Meghan M; Yi, Paul H; Hussein, Khalil I; Cross, Michael B; Della Valle, Craig J

    2017-12-01

    Prior studies indicate that orthopedic patient education materials are written at a level that is too high for the average patient. The purpose of this study was to assess the readability of online patient education materials provided by orthopedic implant manufacturers. All patient education articles available in 2013 from the web sites of the 5 largest orthopedic implant manufacturers were identified. Each article was evaluated with the Flesch-Kincaid (FK) readability test. The number of articles with readability ≤ the eighth-grade level (average reading ability of US adults) and the sixth-grade level (recommended level for patient education materials) was determined. Mean readability levels of each company's articles were compared using analysis of variance (significance set at P articles were reviewed from the 5 largest implant manufacturers. The mean overall FK grade level was 10.9 (range, 3.8-16.1). Only 58 articles (10%) were written ≤ the eighth-grade level, and only 13 (2.2%) were ≤ the sixth-grade level. The mean FK grade level was significantly different among groups (Smith & Nephew = 12.0, Stryker = 11.6, Biomet = 11.3, DePuy = 10.6, Zimmer = 10.1; P education materials from implant manufacturers are written at a level too high to be comprehended by the average patient. Future efforts should be made to improve the readability of orthopedic patient education materials. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Friction wear and dissolution of orthopedic implant systems

    International Nuclear Information System (INIS)

    Ektessabi, A.M.; Shikine, S.; Hamdi, M.; Kitamura, N.; Rokkum, M.; Johansson, C.

    2000-01-01

    Bio-medical implants release metallic elements during the long periods of time while inserted in the human body. The chemical interactions between the tissues and surface of the implants, and the mechanical friction of implants cause the release of metals into the human tissues. In this study we investigated the distribution and the chemical-state of the metallic elements in the tissues around a failed implant system using PIXE (proton induced x-ray emission) and SR-XRF (synchrotron radiation x-ray fluorescence) spectroscopies. The specimens were from the causes of patients with diagnosed arthritis. The implant consisted of a stem and a metal backing made of Ti-6Al-4V, an implant head made of stainless steel, and a polyethylene (PE) cup. Both the stem and the metal backing had a plasma-sprayed HAp surface coating. Distribution and concentration of dissolved elements in tissues surrounding implants were examined and quantified using PIXE analysis. Similar specimen from the same case was further investigated using SR-XRF analysis. Chemical-states of the dissolved elements were also studied by XAFS (x-ray absorption fine structure) analysis. From results of these measurements, it is confirmed that the tissues surrounding implants contained metallic elements such as Fe, Cr, Ni, and Ti. These elements are originated from the implant. Furthermore, it was made clear that the chemical-state of Fe had changed as a consequence of dissolution of Fe in the organic tissues. (author)

  4. Scattering of the radiofrequency electromagnetic field by orthopedic bone support frame implants

    International Nuclear Information System (INIS)

    Mohsin, S.A.; Sheikh, N.M.

    2009-01-01

    The interaction of the fields in MRI (Magnetic Resonance Imaging) with orthopedic implants is investigated. The primary interaction is the scattering of the MRI RF (Radiofrequency) field by the implants. As a specific case study, the scattel-cd field due to a bone support frame implant is computed by the finite-element-method. The support frame has steel pins of significant length embedded in tissue. The induced surface current distributions on the steel pins and the spatial electric field distributions in the surrounding tissue have been obtained. (author)

  5. Mechanical Behavior of Polymer Nano Bio Composite for Orthopedic Implants

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    Marimuthu, K., Dr.; Rajan, Sankar

    2018-04-01

    The bio-based polymer composites have been the focus of many scientific and research projects, as well as many commercial programs. In recent years, scientists and engineers have been working together to use the inherent strength and performance of the new class of bio-based composites which is compactable with human body and can act as a substitute for living cells. In this stage the polymer composites also stepped into human bone implants as a replacement for metallic implants which was problems like corrosion resistance and high cost. The polymer composite have the advantage that it can be molded to the required shape, the polymers have high corrosion resistance, less weight and low cost. The aim of this research is to develop and analyze the suitable bio compactable polymer composite for human implants. The nano particles reinforced polymer composites provides good mechanical properties and shows good tribological properties especially in the total hip and knee replacements. The graphene oxide powders are bio compactable and acts as anti biotic. GO nano powder where reinforced into High-density polyethylene in various weight percentage of 0.5% to 2%. The performance of GO nano powder shows better tribological properties. The material produced does not cause any pollution to the environment and at the same time it can be bio compactable and sustainable. The product will act environmentally friendly.

  6. Sistema de fabrico rápido de implantes ortopédicos Rapid manufacturing system of orthopedics implants

    Directory of Open Access Journals (Sweden)

    Carlos Relvas

    2009-06-01

    Full Text Available Este estudo teve como objectivo o desenvolvimento uma metodologia de fabrico rápido de implantes ortopédicos, em simultaneidade com a intervenção cirúrgica, considerando duas potenciais aplicações na área ortopédica: o fabrico de implantes anatomicamente adaptados e o fabrico de implantes para substituição de perdas ósseas. A inovação do trabalho desenvolvido consiste na obtenção in situ da geometria do implante, através da impressão directa de um material elastomérico (polivinilsiloxano que permite obter com grande exactidão a geometria pretendida. Após digitalização do modelo obtido em material elastomérico, o implante final é fabricado por maquinagem recorrendo a um sistema de CAD/CAM dedicado. O implante após esterilização, pode ser colocado no paciente. O conceito foi desenvolvido com recurso a tecnologias disponíveis comercialmente e de baixo custo. O mesmo foi testado sob a forma de uma artroplastia da anca realizada in vivo numa ovelha. O acréscimo de tempo de cirurgia foi de 80 minutos sendo 40 directamente resultantes do processo de fabrico do implante. O sistema desenvolvido revelou-se eficiente no alcance dos objectivos propostos, possibilitando o fabrico de um implante durante um período de tempo perfeitamente compatível com o tempo de cirurgia.This study, aimed the development of a methodology for rapid manufacture of orthopedic implants simultaneously with the surgical intervention, considering two potential applications in the fields of orthopedics: the manufacture of anatomically adapted implants and implants for bone loss replacement. This work innovation consists on the capitation of the in situ geometry of the implant by direct capture of the shape using an elastomeric material (polyvinylsiloxane which allows fine detail and great accuracy of the geometry. After scanning the elastomeric specimen, the implant is obtained by machining using a CNC milling machine programmed with a dedicated CAD

  7. Improvement on corrosion resistance of NiTi orthopedic materials by carbon plasma immersion ion implantation

    International Nuclear Information System (INIS)

    Poon, Ray W.Y.; Ho, Joan P.Y.; Luk, Camille M.Y.; Liu Xuanyong; Chung, Jonathan C.Y.; Chu, Paul K.; Yeung, Kelvin W.K.; Lu, William W.; Cheung, Kenneth M.C.

    2006-01-01

    Nickel-titanium shape memory alloys (NiTi) have potential applications as orthopedic implants because of their unique super-elastic properties and shape memory effects. However, the problem of out-diffusion of harmful Ni ions from the alloys during prolonged use inside a human body must be overcome before they can be widely used in orthopedic implants. In this work, we enhance the corrosion resistance of NiTi using carbon plasma immersion ion implantation and deposition (PIII and D). Our corrosion and simulated body fluid tests indicate that either an ion-mixed amorphous carbon coating fabricated by PIII and D or direct carbon PIII can drastically improve the corrosion resistance and block the out-diffusion of Ni from the materials. Results of atomic force microscopy (AFM) indicate that both C 2 H 2 -PIII and D and C 2 H 2 -PIII do not roughen the original flat surface to an extent that can lead to degradation in corrosion resistance

  8. An overview of recent advances in designing orthopedic and craniofacial implants.

    Science.gov (United States)

    Mantripragada, Venkata P; Lecka-Czernik, Beata; Ebraheim, Nabil A; Jayasuriya, Ambalangodage C

    2013-11-01

    Great deal of research is still going on in the field of orthopedic and craniofacial implant development to resolve various issues being faced by the industry today. Despite several disadvantages of the metallic implants, they continue to be used, primarily because of their superior mechanical properties. In order to minimize the harmful effects of the metallic implants and its by-products, several modifications are being made to these materials, for instance nickel-free stainless steel, cobalt-chromium and titanium alloys are being introduced to eliminate the toxic effects of nickel being released from the alloys, introduce metallic implants with lower modulus, reduce the cost of these alloys by replacing rare elements with less expensive elements etc. New alloys like tantalum, niobium, zirconium, and magnesium are receiving attention given their satisfying mechanical and biological properties. Non-oxide ceramics like silicon nitride and silicon carbide are being currently developed as a promising implant material possessing a combination of properties such as good wear and corrosion resistance, increased ductility, good fracture and creep resistance, and relatively high hardness in comparison to alumina. Polymer/magnesium composites are being developed to improve mechanical properties as well as retain polymer's property of degradation. Recent advances in orthobiologics are proving interesting as well. This paper thus deals with the latest improvements being made to the existing implant materials and includes new materials being introduced in the field of biomaterials. Copyright © 2013 Wiley Periodicals, Inc.

  9. Implant vendors and hospitals: competing influences over product choice by orthopedic surgeons.

    Science.gov (United States)

    Burns, Lawton R; Housman, Michael G; Booth, Robert E; Koenig, Aaron

    2009-01-01

    Vendors of hip and knee implants court orthopedic surgeons to adopt their products. Hospitals, which have to pay for these products, now court the same surgeons to help reduce the number of vendors and contain implant costs. This study measures the surgeon's perceived alignment of interests with both vendors and hospitals and gauges surgeons' exposure and receptivity to hospital cost-containment efforts. We surveyed all practicing orthopedists performing 12 or more implant procedures annually in Pennsylvania. The survey identified the surgeon's preferred vendor, tenure with that vendor, use of the vendor during residency training, receipt of financial payments from the vendor, alignment of interests with both vendor and hospital stakeholders, and exposure and receptivity to hospital cost-containment efforts. Surgeons have long-standing relationships with implant vendors, but only a small proportion receive financial payments. Surgeons align most closely with the vendor's sales representative and least closely with the hospital's purchasing manager. Paradoxically, surgeons support hospital efforts to limit the number of vendors but report that their own choice of vendor is not constrained. The major drivers of surgeons' alignment and stance toward cost containment are their tenure with and receipt of financial payments from the vendor. Hospitals face a competitive disadvantage in capturing the attention of orthopedists, compared with implant vendors. The vendors' advantage stems from historical, financial, and service benefits offered to surgeons. Hospital executives now seek to offer comparable benefits to surgeons.

  10. Massive subacromial-subdeltoid bursitis with rice bodies secondary to an orthopedic implant.

    Science.gov (United States)

    Urruela, Adriana M; Rapp, Timothy B; Egol, Kenneth A

    2012-09-01

    Both early and late complications following open reduction and internal fixation of proximal humerus fractures have been reported extensively in the literature. Although orthopedic implants are known to cause irritation and inflammation, to our knowledge, this is the first case report to describe a patient with rice bodies secondary to an orthopedic implant. Although the etiology of rice bodies is unclear, histological studies reveal that they are composed of an inner amorphous core surrounded by collagen and fibrin. The differential diagnosis in this case included synovial chondromatosis, infection, and the formation of a malignant tumor. Additional imaging studies, such as magnetic resonance imaging, and more specific tests were necessary to differentiate the rice bodies due to bursitis versus neoplasm, prior to excision. The patient presented 5 years following open reduction and internal fixation of a displaced proximal humerus fracture, with swelling in the area of the previous surgical site. Examination revealed a large, painless tumor-like mass on the anterior aspect of the shoulder. The patient's chief concern was the unpleasant aesthetic of the mass; no pain was reported. Upon excision of the mass, the patient's full, painless range of motion returned.

  11. Anodization: a promising nano-modification technique of titanium implants for orthopedic applications.

    Science.gov (United States)

    Yao, Chang; Webster, Thomas J

    2006-01-01

    Anodization is a well-established surface modification technique that produces protective oxide layers on valve metals such as titanium. Many studies have used anodization to produce micro-porous titanium oxide films on implant surfaces for orthopedic applications. An additional hydrothermal treatment has also been used in conjunction with anodization to deposit hydroxyapatite on titanium surfaces; this is in contrast to using traditional plasma spray deposition techniques. Recently, the ability to create nanometer surface structures (e.g., nano-tubular) via anodization of titanium implants in fluorine solutions have intrigued investigators to fabricate nano-scale surface features that mimic the natural bone environment. This paper will present an overview of anodization techniques used to produce micro-porous titanium oxide structures and nano-tubular oxide structures, subsequent properties of these anodized titanium surfaces, and ultimately their in vitro as well as in vivo biological responses pertinent for orthopedic applications. Lastly, this review will emphasize why anodized titanium structures that have nanometer surface features enhance bone forming cell functions.

  12. C-reactive protein, erythrocyte sedimentation rate and orthopedic implant infection.

    Directory of Open Access Journals (Sweden)

    Kerryl E Piper

    Full Text Available BACKGROUND: C-reactive protein (CRP and erythrocyte sedimentation rate (ESR have been shown to be useful for diagnosis of prosthetic hip and knee infection. Little information is available on CRP and ESR in patients undergoing revision or resection of shoulder arthroplasties or spine implants. METHODS/RESULTS: We analyzed preoperative CRP and ESR in 636 subjects who underwent knee (n=297, hip (n=221 or shoulder (n=64 arthroplasty, or spine implant (n=54 removal. A standardized definition of orthopedic implant-associated infection was applied. Receiver operating curve analysis was used to determine ideal cutoff values for differentiating infected from non-infected cases. ESR was significantly different in subjects with aseptic failure infection of knee (median 11 and 53.5 mm/h, respectively, p=<0.0001 and hip (median 11 and 30 mm/h, respectively, p=<0.0001 arthroplasties and spine implants (median 10 and 48.5 mm/h, respectively, p=0.0033, but not shoulder arthroplasties (median 10 and 9 mm/h, respectively, p=0.9883. Optimized ESR cutoffs for knee, hip and shoulder arthroplasties and spine implants were 19, 13, 26, and 45 mm/h, respectively. Using these cutoffs, sensitivity and specificity to detect infection were 89 and 74% for knee, 82 and 60% for hip, and 32 and 93% for shoulder arthroplasties, and 57 and 90% for spine implants. CRP was significantly different in subjects with aseptic failure and infection of knee (median 4 and 51 mg/l, respectively, p<0.0001, hip (median 3 and 18 mg/l, respectively, p<0.0001, and shoulder (median 3 and 10 mg/l, respectively, p=0.01 arthroplasties, and spine implants (median 3 and 20 mg/l, respectively, p=0.0011. Optimized CRP cutoffs for knee, hip, and shoulder arthroplasties, and spine implants were 14.5, 10.3, 7, and 4.6 mg/l, respectively. Using these cutoffs, sensitivity and specificity to detect infection were 79 and 88% for knee, 74 and 79% for hip, and 63 and 73% for shoulder arthroplasties, and 79 and

  13. Review of the regulations for the use of stainless steels for orthopedic implants in Argentina

    International Nuclear Information System (INIS)

    Daga, Bernardo; Rivera, Graciela; Boeri, Roberto

    2007-01-01

    Motivated by the relatively high rate of failure of orthopedic implants in Argentina, the authors review the current normative regulating the use of stainless steels in the fabrication of these metallic parts in the country, and compare it with the regulations currently in use in other countries. The analysis shows that several standards in effect in the country do not comply with broadly recognized international standards. This situation is aggravated by a recent revision of the normative that failed to improve the quality standards to reach levels similar to those applied in developed countries or even in MERCOSUR associates. The national organization in charge of implant certification in Argentina, complying with the law, accepts the applicability of IRAM standards to certify stainless steels implants. In the opinion of the authors, the current practice used to certify implants does not guarantee the structural stability and biocompatibility of the devices, increasing the risk of failure in service, and escalating the cost of the public health care system

  14. Hydrogel delivery of lysostaphin eliminates orthopedic implant infection by Staphylococcus aureus and supports fracture healing.

    Science.gov (United States)

    Johnson, Christopher T; Wroe, James A; Agarwal, Rachit; Martin, Karen E; Guldberg, Robert E; Donlan, Rodney M; Westblade, Lars F; García, Andrés J

    2018-05-29

    Orthopedic implant infections are a significant clinical problem, with current therapies limited to surgical debridement and systemic antibiotic regimens. Lysostaphin is a bacteriolytic enzyme with high antistaphylococcal activity. We engineered a lysostaphin-delivering injectable PEG hydrogel to treat Staphylococcus aureus infections in bone fractures. The injectable hydrogel formulation adheres to exposed tissue and fracture surfaces, ensuring efficient, local delivery of lysostaphin. Lysostaphin encapsulation within this synthetic hydrogel maintained enzyme stability and activity. Lysostaphin-delivering hydrogels exhibited enhanced antibiofilm activity compared with soluble lysostaphin. Lysostaphin-delivering hydrogels eradicated S. aureus infection and outperformed prophylactic antibiotic and soluble lysostaphin therapy in a murine model of femur fracture. Analysis of the local inflammatory response to infections treated with lysostaphin-delivering hydrogels revealed indistinguishable differences in cytokine secretion profiles compared with uninfected fractures, demonstrating clearance of bacteria and associated inflammation. Importantly, infected fractures treated with lysostaphin-delivering hydrogels fully healed by 5 wk with bone formation and mechanical properties equivalent to those of uninfected fractures, whereas fractures treated without the hydrogel carrier were equivalent to untreated infections. Finally, lysostaphin-delivering hydrogels eliminate methicillin-resistant S. aureus infections, supporting this therapy as an alternative to antibiotics. These results indicate that lysostaphin-delivering hydrogels effectively eliminate orthopedic S. aureus infections while simultaneously supporting fracture repair. Copyright © 2018 the Author(s). Published by PNAS.

  15. Insight of magnesium alloys and composites for orthopedic implant applications – a review

    Directory of Open Access Journals (Sweden)

    R Radha

    2017-09-01

    Full Text Available Magnesium (Mg and its alloys have been widely researched for orthopedic applications recently. Mg alloys have stupendous advantages over the commercially available stainless steel, Co-Cr-Ni alloy and titanium implants. Till date, extensive mechanical, in-vitro and in-vivo studies have been done to improve the biomedical performance of Mg alloys through alloying, processing conditions, surface modification etc. This review comprehensively describes the strategies for improving the mechanical and degradation performance of Mg alloys through properly tailoring the composition of alloying elements, reinforcements and processing techniques. It also highlights the status and progress of research in to (i the selection of nutrient elements for alloying, reinforcement and its effects (ii type of Mg alloy system (binary, ternary and quaternary and composites (iii grain refinement for strengthening through severe plastic deformation techniques. Furthermore it also emphasizes on the importance of Mg composites with regard to hard tissue applications.

  16. High-strength, surface-porous polyether-ether-ketone for load-bearing orthopedic implants.

    Science.gov (United States)

    Evans, Nathan T; Torstrick, F Brennan; Lee, Christopher S D; Dupont, Kenneth M; Safranski, David L; Chang, W Allen; Macedo, Annie E; Lin, Angela S P; Boothby, Jennifer M; Whittingslow, Daniel C; Carson, Robert A; Guldberg, Robert E; Gall, Ken

    2015-02-01

    Despite its widespread clinical use in load-bearing orthopedic implants, polyether-ether-ketone (PEEK) is often associated with poor osseointegration. In this study, a surface-porous PEEK material (PEEK-SP) was created using a melt extrusion technique. The porous layer was 399.6±63.3 μm thick and possessed a mean pore size of 279.9±31.6 μm, strut spacing of 186.8±55.5 μm, porosity of 67.3±3.1% and interconnectivity of 99.9±0.1%. Monotonic tensile tests showed that PEEK-SP preserved 73.9% of the strength (71.06±2.17 MPa) and 73.4% of the elastic modulus (2.45±0.31 GPa) of as-received, injection-molded PEEK. PEEK-SP further demonstrated a fatigue strength of 60.0 MPa at one million cycles, preserving 73.4% of the fatigue resistance of injection-molded PEEK. Interfacial shear testing showed the pore layer shear strength to be 23.96±2.26 MPa. An osseointegration model in the rat revealed substantial bone formation within the pore layer at 6 and 12 weeks via microcomputed tomography and histological evaluation. Ingrown bone was more closely apposed to the pore wall and fibrous tissue growth was reduced in PEEK-SP when compared to non-porous PEEK controls. These results indicate that PEEK-SP could provide improved osseointegration while maintaining the structural integrity necessary for load-bearing orthopedic applications. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  17. Nanoparticulate zinc oxide as a coating material for orthopedic and dental implants.

    Science.gov (United States)

    Memarzadeh, Kaveh; Sharili, Amir S; Huang, Jie; Rawlinson, Simon C F; Allaker, Robert P

    2015-03-01

    Orthopedic and dental implants are prone to infection. In this study, we describe a novel system using zinc oxide nanoparticles (nZnO) as a coating material to inhibit bacterial adhesion and promote osteoblast growth. Electrohydrodynamic atomisation (EHDA) was employed to deposit mixtures of nZnO and nanohydroxyapatite (nHA) onto the surface of glass substrates. Nano-coated substrates were exposed to Staphylococcus aureus suspended in buffered saline or bovine serum to determine antimicrobial activity. Our results indicate that 100% nZnO and 75% nZnO/25% nHA composite-coated substrates have significant antimicrobial activity. Furthermore, osteoblast function was explored by exposing cells to nZnO. UMR-106 cells exposed to nZnO supernatants showed minimal toxicity. Similarly, MG-63 cells cultured on nZnO substrates did not show release of TNF-α and IL-6 cytokines. These results were reinforced by both proliferation and differentiation studies which revealed that a substrate coated with exclusively nZnO is more efficient than composite surface coatings. Finally, electron and light microscopy, together with immunofluorescence staining, revealed that all cell types tested, including human mesenchymal cell (hMSC), were able to maintain normal cell morphology when adhered onto the surface of the nano-coated substrates. Collectively, these findings indicate that nZnO can, on its own, provide an optimal coating for future bone implants that are both antimicrobial and biocompatible. © 2014 Wiley Periodicals, Inc.

  18. Diamond-like carbon coatings with zirconium-containing interlayers for orthopedic implants.

    Science.gov (United States)

    Choudhury, Dipankar; Lackner, Juergen; Fleming, Robert A; Goss, Josh; Chen, Jingyi; Zou, Min

    2017-04-01

    Six types of diamond-like carbon (DLC) coatings with zirconium (Zr)-containing interlayers on titanium alloy (Ti-6Al-4V) were investigated for improving the biotribological performance of orthopedic implants. The coatings consist of three layers: above the substrate a layer stack of 32 alternating Zr and ZrN sublayers (Zr:ZrN), followed by a layer comprised of Zr and DLC (Zr:DLC), and finally a N-doped DLC layer. The Zr:ZrN layer is designed for increasing load carrying capacity and corrosion resistance; the Zr:DLC layer is for gradual transition of stress, thus enhancing layer adhesion; and the N-doped DLC layer is for decreasing friction, squeaking noises and wear. Biotribological experiments were performed in simulated body fluid employing a ball-on-disc contact with a Si 3 N 4 ball and a rotational oscillating motion to mimic hip motion in terms of gait angle, dynamic contact pressures, speed and body temperature. The results showed that the Zr:DLC layer has a substantial influence on eliminating delamination of the DLC from the substrates. The DLC/Si 3 N 4 pairs significantly reduced friction coefficient, squeaking noise and wear of both the Si 3 N 4 balls and the discs compared to those of the Ti-6Al-4V/Si 3 N 4 pair after testing for a duration that is equivalent to one year of hip motion in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A low power cyclic ADC design for a wireless monitoring system for orthopedic implants

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yi; Li Fule; Chen Hong; Zhang Chun; Wang Zhihua, E-mail: chenyi02@mails.tsinghua.edu.c [Tsinghua National Laboratory for Information Science and Technology, Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

    2009-08-15

    This paper presents a low power cyclic analog-to-digital convertor (ADC) design for a wireless monitoring system for orthopedic implants. A two-stage cyclic structure including a single to differential converter, two multiplying DAC functional blocks (MDACs) and some comparators is adopted, which brings moderate speed and moderate resolution with low power consumption. The MDAC is implemented with the common switched capacitor method. The 1.5-bit stage greatly simplifies the design of the comparator. The operational amplifier is carefully optimized both in schematic and layout for low power and offset. The prototype chip has been fabricated in a United Microelectronics Corporation (UMC) 0.18-{mu}m 1P6M CMOS process. The core of the ADC occupies only 0.12 mm{sup 2}. With a 304.7-Hz input and 4-kHz sampling rate, the measured peak SNDR and SFDR are 47.1 dB and 57.8 dBc respectively and its DNL and INL are 0.27 LSB and 0.3 LSB, respectively. The power consumption of the ADC is only 12.5 {mu}W in normal working mode and less than 150 nW in sleep mode. (semiconductor integrated circuits)

  20. In vitro study of nanostructured diopside coating on Mg alloy orthopedic implants

    International Nuclear Information System (INIS)

    Razavi, Mehdi; Fathi, Mohammadhossein; Savabi, Omid; Vashaee, Daryoosh; Tayebi, Lobat

    2014-01-01

    The high corrosion rate of Mg alloys has hindered their application in various areas, particularly for orthopedic applications. In order to decrease the corrosion rate and to improve the bioactivity, mechanical stability and cytocompatibility of the Mg alloy, nanostructured diopside (CaMgSi 2 O 6 ) has been coated on AZ91 Mg alloy using a combined micro arc oxidation (MAO) and electrophoretic deposition (EPD) method. The crystalline structure, the morphology and the composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Electrochemical corrosion test, immersion test, and compression test were used to evaluate the corrosion resistance, the in vitro bioactivity and the mechanical stability of the samples, respectively. The cytocompatibility of the samples was tested by the cell viability and the cell attachment of L-929 cells. The results confirmed that the diopside coating not only slows down the corrosion rate, but also enhances the in vitro bioactivity, mechanical stability and cytocompatibility of AZ91 Mg alloy. Therefore, Mg alloy coated with nanostructured diopside offers a promising approach for biodegradable bone implants. - Highlights: • The diopside coating was applied on Mg alloy using the combined MAO and EPD methods. • The corrosion resistance of the diopside coated Mg alloy was noticeably improved. • The in vitro bioactivity of the diopside coated Mg alloy was considerably increased. • The mechanical stability of biodegradable Mg alloy was enhanced by diopside coating. • The cytocompatibility of the Mg alloy was improved employing diopside coating

  1. Evaluation of MR issues for the latest standard brands of orthopedic metal implants: Plates and screws

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Yue-fen, E-mail: zou_yf@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, No. 300 Guangzhou Road, Nanjing (China); Chu, Bin, E-mail: 18262636700@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, No. 300 Guangzhou Road, Nanjing (China); Wang, Chuan-bing, E-mail: wangchuanb_csr@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, No. 300 Guangzhou Road, Nanjing (China); Hu, Zhi-yi, E-mail: huzhiyi@medmail.com.cn [Department of Spine Surgery, The First Affiliated Hospital of Nanjing Medical University, No. 300 Guangzhou Road, Nanjing (China)

    2015-03-15

    Highlights: •Although previous studies have indicated that most of the orthopedic implants are compatible in MR imaging system especially for titanium alloy, there are still concerns about the safety of patients with stainless steel implants, who were refused to a MR scan in most cases in our country. •In this study, it was verified that both titanium alloy and stainless steel materials (plates and screws) cause a weak force and low MRI-related heating at a 1.5-T or less, which do not pose an additional hazard or risk to patients. In addition, we also had explored the influence of different sequences and parameters on size of metallic artifacts to obtain optimized pulse sequences with appropriate parameters for reducing artifacts, which would be convenient and useful in clinical work. -- Abstract: Purpose: The study was performed to evaluate magnetic resonance (MR) issues for the latest standard brands of plates and screws used in orthopedic surgery at a 1.5-T MR system, including the safety and metallic artifacts. Methods: The plates and screws (made of titanium alloy and stainless steel materials, according to the latest standard brands) were assessed for displacement in degrees, MRI-related heating and artifacts at a 1.5-T MR system. The displacement in degrees of the plates and screws was evaluated on an angel-measurement instrument at the entrance of the MR scanner. The MRI-related heating was assessed on a swine leg fixed with a plate by using a “worst-case” pulse sequence. A rectangular water phantom was designed to evaluate metallic artifacts of a screw on different sequences (T1/T2-weighted FSE, STIR, T2-FSE fat saturation, GRE, DWI) and then artifacts were evaluated on T2-weighted FSE sequence by modifying the scanning parameters including field of view (FOV), echo train length (ETL) and bandwidth to identify the influence of parameters on metallic artifacts. 15 volunteers with internal vertebral fixation (titanium alloy materials) were scanned

  2. Evaluation of MR issues for the latest standard brands of orthopedic metal implants: Plates and screws

    International Nuclear Information System (INIS)

    Zou, Yue-fen; Chu, Bin; Wang, Chuan-bing; Hu, Zhi-yi

    2015-01-01

    Highlights: •Although previous studies have indicated that most of the orthopedic implants are compatible in MR imaging system especially for titanium alloy, there are still concerns about the safety of patients with stainless steel implants, who were refused to a MR scan in most cases in our country. •In this study, it was verified that both titanium alloy and stainless steel materials (plates and screws) cause a weak force and low MRI-related heating at a 1.5-T or less, which do not pose an additional hazard or risk to patients. In addition, we also had explored the influence of different sequences and parameters on size of metallic artifacts to obtain optimized pulse sequences with appropriate parameters for reducing artifacts, which would be convenient and useful in clinical work. -- Abstract: Purpose: The study was performed to evaluate magnetic resonance (MR) issues for the latest standard brands of plates and screws used in orthopedic surgery at a 1.5-T MR system, including the safety and metallic artifacts. Methods: The plates and screws (made of titanium alloy and stainless steel materials, according to the latest standard brands) were assessed for displacement in degrees, MRI-related heating and artifacts at a 1.5-T MR system. The displacement in degrees of the plates and screws was evaluated on an angel-measurement instrument at the entrance of the MR scanner. The MRI-related heating was assessed on a swine leg fixed with a plate by using a “worst-case” pulse sequence. A rectangular water phantom was designed to evaluate metallic artifacts of a screw on different sequences (T1/T2-weighted FSE, STIR, T2-FSE fat saturation, GRE, DWI) and then artifacts were evaluated on T2-weighted FSE sequence by modifying the scanning parameters including field of view (FOV), echo train length (ETL) and bandwidth to identify the influence of parameters on metallic artifacts. 15 volunteers with internal vertebral fixation (titanium alloy materials) were scanned

  3. Evaluation of MR issues for the latest standard brands of orthopedic metal implants: plates and screws.

    Science.gov (United States)

    Zou, Yue-Fen; Chu, Bin; Wang, Chuan-Bing; Hu, Zhi-Yi

    2015-03-01

    The study was performed to evaluate magnetic resonance (MR) issues for the latest standard brands of plates and screws used in orthopedic surgery at a 1.5-T MR system, including the safety and metallic artifacts. The plates and screws (made of titanium alloy and stainless steel materials, according to the latest standard brands) were assessed for displacement in degrees, MRI-related heating and artifacts at a 1.5-T MR system. The displacement in degrees of the plates and screws was evaluated on an angel-measurement instrument at the entrance of the MR scanner. The MRI-related heating was assessed on a swine leg fixed with a plate by using a "worst-case" pulse sequence. A rectangular water phantom was designed to evaluate metallic artifacts of a screw on different sequences (T1/T2-weighted FSE, STIR, T2-FSE fat saturation, GRE, DWI) and then artifacts were evaluated on T2-weighted FSE sequence by modifying the scanning parameters including field of view (FOV), echo train length (ETL) and bandwidth to identify the influence of parameters on metallic artifacts. 15 volunteers with internal vertebral fixation (titanium alloy materials) were scanned with MR using axial and sagittal T2-FSE, sagittal T2-FSE fat suppression and STIR with conventional and optimized parameters, respectively. Then all images were graded by two experienced radiologists having the experience of more than 7 years under double-blind studies that is neither of them knew which was conventional parameter group and optimized parameter group. The average deflection angle of titanium alloy and stainless steel implants were 4.3° and 7.7°, respectively, (less than 45°) which indicated that the magnetically induced force was less than the weight of the object. The deflection angle of the titanium alloy implants was less than the stainless steel one (t=9.69, Ptitanium alloy before and after the scan was 0.48°C and stainless steel implants was 0.74°C, respectively, with the background temperature

  4. Investigating the structure and biocompatibility of niobium and titanium oxides as coatings for orthopedic metallic implants.

    Science.gov (United States)

    Pradhan, D; Wren, A W; Misture, S T; Mellott, N P

    2016-01-01

    Applying sol gel based coatings to orthopedic metallic implant materials can significantly improve their properties and lifespan in vivo. For this work, niobium (Nb2O5) and titanium (TiO2) oxides were prepared via solution processing in order to determine the effect of atomic arrangement (amorphous/crystalline) on bioactivity. Thermal evaluation on the synthesized materials identified an endotherm for Nb2O5 at 75 °C with 40% weight loss below 400 °C, and minimal weight loss between 400 and 850 °C. Regarding TiO2 an endotherm was present at 92 °C with 25% weight loss below 400 °C, and 4% between 400 and 850 °C. Phase evolution was determined using High Temperature X-ray Diffraction (HT-XRD) where amorphous-Nb2O5 (450 °C), hexagonal-Nb2O5 (525 °C), orthorhombic-Nb2O5 (650 °C), amorphous-TiO2 (275 °C) and tetragonal TiO2 (500 °C) structures were produced. Simulated body fluid (SBF) testing was conducted over 1, 7 and 30 days and resulted in positive chemical and morphological changes for crystalline Nb2O5 (525 °C) and TiO2 (500 °C) after 30 days of incubation. Rod-like CaP deposits were observed on the surfaces using Scanning Electron Microscopy (FE-SEM) and Grazing Incidence-X-ray Diffraction (GI-XRD) shows that the deposits were X-ray amorphous. Cell viability was higher with the TiO2 (122%) samples when compared to the growing cell population while Nb2O5 samples exhibited a range of viability (64-105%), partially dependent on materials atomic structure. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Prevalence and antibiotic resistance of 15 minor staphylococcal species colonizing orthopedic implants.

    Science.gov (United States)

    Arciola, C R; Campoccia, D; An, Y H; Baldassarri, L; Pirini, V; Donati, M E; Pegreffi, F; Montanaro, L

    2006-04-01

    Several species belonging to Staphylococcus genus (non Sau/ non Sep species) exhibit increasing abilities as opportunistic pathogens in colonisation of periprosthesis tissues. Here we report on antibiotic resistance of 193 strains, belonging to non Sau/ non Sep species, consecutively collected from orthopedic implant infections in a period of about 40 months. The 193 strains (representing 17% of all staphylococci isolated) were analysed for their antibiotic resistance to 16 different drugs. Five species turned out more prevalent, ranging from 1 to 5%: S. hominis (4.2%), S. haemolyticus (3.7%), S. capitis (2.7%), S. warneri (2.6%), and S. cohnii (1.6%). Among these, the prevalence of antibiotic resistance to penicillins was similar, ranging from 51% to 66%. Conversely, significant differences were observed for all the remaining antibiotics. For S. haemolyticus the resistances to oxacillin and imipenem, the four aminoglycosides and erythromycin were at least twice that of the other three species which were compared. S. warneri was on the contrary the species with the lowest occurrence of resistant strains. Ten species appeared only rarely at the infection sites: S. lugdunensis, S. caprae, S. equorum, S. intermedius, S. xylosus, S. simulans, S. saprophyticus, S. pasteuri, S. sciuri, and S. schleiferi. The behaviours of these species, often resistant to penicillins, were individually analysed. Differences in both the frequencies and the panels of antibiotic resistances observed among the non Sau/ non Sep species: i) suggest that horizontal spreading of resistance factors, if acting, was not sufficient per se to level their bio-diversities; ii) highlight and confirm the worrisome appearance within the Staphylococcus genus of emerging "new pathogens", not homogeneous for their virulence and antibiotic resistance prevalence, which deserve to be recognised and treated individually.

  6. In vitro study of nanostructured diopside coating on Mg alloy orthopedic implants

    Energy Technology Data Exchange (ETDEWEB)

    Razavi, Mehdi, E-mail: mehdi.razavi@okstate.edu [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Fathi, Mohammadhossein [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Dental Materials Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Savabi, Omid [Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); Vashaee, Daryoosh [School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Tayebi, Lobat, E-mail: lobat.tayebi@okstate.edu [School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States)

    2014-08-01

    The high corrosion rate of Mg alloys has hindered their application in various areas, particularly for orthopedic applications. In order to decrease the corrosion rate and to improve the bioactivity, mechanical stability and cytocompatibility of the Mg alloy, nanostructured diopside (CaMgSi{sub 2}O{sub 6}) has been coated on AZ91 Mg alloy using a combined micro arc oxidation (MAO) and electrophoretic deposition (EPD) method. The crystalline structure, the morphology and the composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Electrochemical corrosion test, immersion test, and compression test were used to evaluate the corrosion resistance, the in vitro bioactivity and the mechanical stability of the samples, respectively. The cytocompatibility of the samples was tested by the cell viability and the cell attachment of L-929 cells. The results confirmed that the diopside coating not only slows down the corrosion rate, but also enhances the in vitro bioactivity, mechanical stability and cytocompatibility of AZ91 Mg alloy. Therefore, Mg alloy coated with nanostructured diopside offers a promising approach for biodegradable bone implants. - Highlights: • The diopside coating was applied on Mg alloy using the combined MAO and EPD methods. • The corrosion resistance of the diopside coated Mg alloy was noticeably improved. • The in vitro bioactivity of the diopside coated Mg alloy was considerably increased. • The mechanical stability of biodegradable Mg alloy was enhanced by diopside coating. • The cytocompatibility of the Mg alloy was improved employing diopside coating.

  7. Effect of a preoperative decontamination protocol on surgical site infections in patients undergoing elective orthopedic surgery with hardware implantation.

    Science.gov (United States)

    Bebko, Serge P; Green, David M; Awad, Samir S

    2015-05-01

    Surgical site infections (SSIs), commonly caused by methicillin-resistant Staphylococcus aureus (MRSA), are associated with significant morbidity and mortality, specifically when hardware is implanted in the patient. Previously, we have demonstrated that a preoperative decontamination protocol using chlorhexidine gluconate washcloths and intranasal antiseptic ointment is effective in eradicating MRSA in the nose and on the skin of patients. To examine the effect of a decontamination protocol on SSIs in patients undergoing elective orthopedic surgery with hardware implantation. A prospective database of patients undergoing elective orthopedic surgery with hardware implantation at the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Texas, was analyzed from October 1, 2012, to December 31, 2013. Cohort groups before and after the intervention were compared. Starting in May 2013, during their preoperative visit, all of the patients watched an educational video about MRSA decontamination and were given chlorhexidine washcloths and oral rinse and nasal povidone-iodine solution to be used the night before and the morning of scheduled surgery. Thirty-day SSI rates were collected according to the definitions of the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance. Data on demographics, comorbidities such as chronic obstructive pulmonary disease and coronary artery disease, tobacco use, alcohol use, and body mass index were also collected. Univariate analysis was performed between the 2 groups of patients. Multivariate analysis was used to identify independent predictors of SSI. A total of 709 patients were analyzed (344 controls and 365 patients who were decolonized). Both groups were well matched with no significant differences in age, body mass index, sex, or comorbidities. All of the patients (100%) completed the MRSA decontamination protocol. The SSI rate in the intervention group was significantly lower (1.1%; 4 of

  8. Value of monoenergetic dual-energy CT (DECT) for artefact reduction from metallic orthopedic implants in post-mortem studies.

    Science.gov (United States)

    Filograna, Laura; Magarelli, Nicola; Leone, Antonio; Guggenberger, Roman; Winklhofer, Sebastian; Thali, Michael John; Bonomo, Lorenzo

    2015-09-01

    The aim of this ex vivo study was to assess the performance of monoenergetic dual-energy CT (DECT) reconstructions to reduce metal artefacts in bodies with orthopedic devices in comparison with standard single-energy CT (SECT) examinations in forensic imaging. Forensic and clinical impacts of this study are also discussed. Thirty metallic implants in 20 consecutive cadavers with metallic implants underwent both SECT and DECT with a clinically suitable scanning protocol. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. Image quality of the seven monoenergetic images and of the corresponding SECT image was assessed qualitatively and quantitatively by visual rating and measurements of attenuation changes induced by streak artefact. Qualitative and quantitative analyses showed statistically significant differences between monoenergetic DECT extrapolated images and SECT, with improvements in diagnostic assessment in monoenergetic DECT at higher monoenergies. The mean value of OPTkeV was 137.6 ± 4.9 with a range of 130 to 148 keV. This study demonstrates that monoenergetic DECT images extrapolated at high energy levels significantly reduce metallic artefacts from orthopedic implants and improve image quality compared to SECT examination in forensic imaging.

  9. Value of monoenergetic dual-energy CT (DECT) for artefact reduction from metallic orthopedic implants in post-mortem studies

    International Nuclear Information System (INIS)

    Filograna, Laura; Magarelli, Nicola; Leone, Antonio; Bonomo, Lorenzo; Guggenberger, Roman; Winklhofer, Sebastian; Thali, Michael John

    2015-01-01

    The aim of this ex vivo study was to assess the performance of monoenergetic dual-energy CT (DECT) reconstructions to reduce metal artefacts in bodies with orthopedic devices in comparison with standard single-energy CT (SECT) examinations in forensic imaging. Forensic and clinical impacts of this study are also discussed. Thirty metallic implants in 20 consecutive cadavers with metallic implants underwent both SECT and DECT with a clinically suitable scanning protocol. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. Image quality of the seven monoenergetic images and of the corresponding SECT image was assessed qualitatively and quantitatively by visual rating and measurements of attenuation changes induced by streak artefact. Qualitative and quantitative analyses showed statistically significant differences between monoenergetic DECT extrapolated images and SECT, with improvements in diagnostic assessment in monoenergetic DECT at higher monoenergies. The mean value of OPTkeV was 137.6 ± 4.9 with a range of 130 to 148 keV. This study demonstrates that monoenergetic DECT images extrapolated at high energy levels significantly reduce metallic artefacts from orthopedic implants and improve image quality compared to SECT examination in forensic imaging. (orig.)

  10. Value of monoenergetic dual-energy CT (DECT) for artefact reduction from metallic orthopedic implants in post-mortem studies

    Energy Technology Data Exchange (ETDEWEB)

    Filograna, Laura [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland); Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Rome (Italy); Magarelli, Nicola; Leone, Antonio; Bonomo, Lorenzo [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Rome (Italy); Guggenberger, Roman; Winklhofer, Sebastian [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Thali, Michael John [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland)

    2015-09-15

    The aim of this ex vivo study was to assess the performance of monoenergetic dual-energy CT (DECT) reconstructions to reduce metal artefacts in bodies with orthopedic devices in comparison with standard single-energy CT (SECT) examinations in forensic imaging. Forensic and clinical impacts of this study are also discussed. Thirty metallic implants in 20 consecutive cadavers with metallic implants underwent both SECT and DECT with a clinically suitable scanning protocol. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. Image quality of the seven monoenergetic images and of the corresponding SECT image was assessed qualitatively and quantitatively by visual rating and measurements of attenuation changes induced by streak artefact. Qualitative and quantitative analyses showed statistically significant differences between monoenergetic DECT extrapolated images and SECT, with improvements in diagnostic assessment in monoenergetic DECT at higher monoenergies. The mean value of OPTkeV was 137.6 ± 4.9 with a range of 130 to 148 keV. This study demonstrates that monoenergetic DECT images extrapolated at high energy levels significantly reduce metallic artefacts from orthopedic implants and improve image quality compared to SECT examination in forensic imaging. (orig.)

  11. Investigating the structure and biocompatibility of niobium and titanium oxides as coatings for orthopedic metallic implants

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, D.; Wren, A.W.; Misture, S.T.; Mellott, N.P., E-mail: mellott@alfred.edu

    2016-01-01

    Applying sol gel based coatings to orthopedic metallic implant materials can significantly improve their properties and lifespan in vivo. For this work, niobium (Nb{sub 2}O{sub 5}) and titanium (TiO{sub 2}) oxides were prepared via solution processing in order to determine the effect of atomic arrangement (amorphous/crystalline) on bioactivity. Thermal evaluation on the synthesized materials identified an endotherm for Nb{sub 2}O{sub 5} at 75 °C with 40% weight loss below 400 °C, and minimal weight loss between 400 and 850 °C. Regarding TiO{sub 2} an endotherm was present at 92 °C with 25% weight loss below 400 °C, and 4% between 400 and 850 °C. Phase evolution was determined using High Temperature X-ray Diffraction (HT-XRD) where amorphous-Nb{sub 2}O{sub 5} (450 °C), hexagonal-Nb{sub 2}O{sub 5} (525 °C), orthorhombic-Nb{sub 2}O{sub 5} (650 °C), amorphous-TiO{sub 2} (275 °C) and tetragonal TiO{sub 2} (500 °C) structures were produced. Simulated body fluid (SBF) testing was conducted over 1, 7 and 30 days and resulted in positive chemical and morphological changes for crystalline Nb{sub 2}O{sub 5} (525 °C) and TiO{sub 2} (500 °C) after 30 days of incubation. Rod-like CaP deposits were observed on the surfaces using Scanning Electron Microscopy (FE-SEM) and Grazing Incidence-X-ray Diffraction (GI-XRD) shows that the deposits were X-ray amorphous. Cell viability was higher with the TiO{sub 2} (122%) samples when compared to the growing cell population while Nb{sub 2}O{sub 5} samples exhibited a range of viability (64–105%), partially dependent on materials atomic structure. - Highlights: • Niobium and titanium oxides were prepared to determine the effect of structure on bioactivity. • Simulated body fluid testing resulted in positive surface chemical and morphological changes. • Amorphous, rod-like CaP deposits were observed on the surfaces. • Niobium oxide exhibited a range of viability partially dependent on materials atomic structure.

  12. Analyses and comparison of a novel, hybrid, multifunctional orthopedic composite and implant

    Science.gov (United States)

    Dicicco, Michael

    In the orthopedic/medical device industry, 2, 2' -bis-(4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (Bis-GMA)- and diurethanedimethacrylate (DUDMA)-based polymeric biomaterials have become well-known substitutes for polymethylmethacrylate (PMMA)- and ultra-high molecular weight polyethylene (UHMWPE)-based biomaterials, respectively. The development of these polymeric biomaterials cannot continue without direct comparison studies against currently marketed materials. The initiative for this research stems wholly from developing analytical methodologies that assist in qualifying novel biomaterials under development, by evaluating their chemical properties, performance, and safety. The goals of this research were: (i) Characterize the assay/quality of every resin component and quantify elution of extractable monomers from novel, DUDMA-based RHAKOSS(TM) implant, (ii) Determine degree of conversion (alpha) and rate of polymerization (Rp) for novel, Bis-GMA-based CORTOSS(TM) composite, (iii) Assess risk for radical-induced post-surgical cytotoxicity for CORTOSS, (iv) Determine if surface radical chemistries occur for sterilized RHAKOSS and assess its oxidative stability, and (v) Quantify antibiotic elution from antibiotic-impregnated CORTOSS and identify factors that control elution. The phenomena studied necessitated the utilization of several analytical spectroscopic techniques; fluorometry, differential scanning calorimetry (DSC), electron paramagnetic resonance (EPR), ultraviolet-visible (UV-VIS), attenuated total reflectance---Fourier-transform infrared (ATR-FTIR), and high performance liquid chromatography (HPLC). A battery of lateral chemical techniques were employed as well; including molecular derivatization/tagging, phase partitioning, spin-trapping, and thermal annealing. Results demonstrated that RHAKOSS monomer percent compositions were prepared according to formulations and monomer elution was virtually undetectable, serving as an empirical gauge to

  13. Customizable cap implants for neurophysiological experimentation.

    Science.gov (United States)

    Blonde, Jackson D; Roussy, Megan; Luna, Rogelio; Mahmoudian, Borna; Gulli, Roberto A; Barker, Kevin C; Lau, Jonathan C; Martinez-Trujillo, Julio C

    2018-04-22

    Several primate neurophysiology laboratories have adopted acrylic-free, custom-fit cranial implants. These implants are often comprised of titanium or plastic polymers, such as polyether ether ketone (PEEK). Titanium is favored for its mechanical strength and osseointegrative properties whereas PEEK is notable for its lightweight, machinability, and MRI compatibility. Recent titanium/PEEK implants have proven to be effective in minimizing infection and implant failure, thereby prolonging experiments and optimizing the scientific contribution of a single primate. We created novel, customizable PEEK 'cap' implants that contour to the primate's skull. The implants were created using MRI and/or CT data, SolidWorks software and CNC-machining. Three rhesus macaques were implanted with a PEEK cap implant. Head fixation and chronic recordings were successfully performed. Improvements in design and surgical technique solved issues of granulation tissue formation and headpost screw breakage. Primate cranial implants have traditionally been fastened to the skull using acrylic and anchor screws. This technique is prone to skin recession, infection, and implant failure. More recent methods have used imaging data to create custom-fit titanium/PEEK implants with radially extending feet or vertical columns. Compared to our design, these implants are more surgically invasive over time, have less force distribution, and/or do not optimize the utilizable surface area of the skull. Our PEEK cap implants served as an effective and affordable means to perform electrophysiological experimentation while reducing surgical invasiveness, providing increased strength, and optimizing useful surface area. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  14. Cobalt-alloy implant debris induce HIF-1α hypoxia associated responses: a mechanism for metal-specific orthopedic implant failure.

    Directory of Open Access Journals (Sweden)

    Lauryn Samelko

    Full Text Available The historical success of orthopedic implants has been recently tempered by unexpected pathologies and early failures of some types of Cobalt-Chromium-Molybdenum alloy containing artificial hip implants. Hypoxia-associated responses to Cobalt-alloy metal debris were suspected as mediating this untoward reactivity at least in part. Hypoxia Inducible Factor-1α is a major transcription factor involved in hypoxia, and is a potent coping mechanism for cells to rapidly respond to changing metabolic demands. We measured signature hypoxia associated responses (i.e. HIF-1α, VEGF and TNF-α to Cobalt-alloy implant debris both in vitro (using a human THP-1 macrophage cell line and primary human monocytes/macrophages and in vivo. HIF-1α in peri-implant tissues of failed metal-on-metal implants were compared to similar tissues from people with metal-on-polymer hip arthroplasties, immunohistochemically. Increasing concentrations of cobalt ions significantly up-regulated HIF-1α with a maximal response at 0.3 mM. Cobalt-alloy particles (1 um-diameter, 10 particles/cell induced significantly elevated HIF-1α, VEGF, TNF-α and ROS expression in human primary macrophages whereas Titanium-alloy particles did not. Elevated expression of HIF-1α was found in peri-implant tissues and synovial fluid of people with failing Metal-on-Metal hips (n = 5 compared to failed Metal-on-Polymer articulating hip arthroplasties (n = 10. This evidence suggests that Cobalt-alloy, more than other metal implant debris (e.g. Titanium alloy, can elicit hypoxia-like responses that if unchecked can lead to unusual peri-implant pathologies, such as lymphocyte infiltration, necrosis and excessive fibrous tissue growths.

  15. How to Choose between the Implant Materials Steel and Titanium in Orthopedic Trauma Surgery: Part 2 - Biological Aspects.

    Science.gov (United States)

    Perren, S M; Regazzoni, P; Fernandez, A A

    2017-01-01

    BIOLOGICAL ASPECTS OF STEEL AND TITANIUM AS IMPLANT MATERIAL IN ORTHOPEDIC TRAUMA SURGERY The following case from the ICUC database, where a titanium plate was implanted into a flourishing infection, represents the clinical experience leading to preferring titanium over steel. (Fig. 1) (6). Current opinions regarding biological aspects of implant function. The "street" opinions regarding the biological aspects of the use of steel versus titanium as a surgical trauma implant material differ widely. Statements of opinion leaders range from "I do not see any difference in the biological behavior between steel and titanium in clinical application" to "I successfully use titanium implants in infected areas in a situation where steel would act as foreign body "sustaining" infection." Furthermore, some comments imply that clinical proof for the superiority of titanium in human application is lacking. The following tries to clarify the issues addressing the different aspects more through a practical clinical approach than a purely scientific one, this includes simplifications. Today's overall biocompatibility of implant materials is acceptable but: As the vast majority of secondary surgeries are elective procedures this allows the selection of implant materials with optimal infection resistance. The different biological reactions of stainless steel and titanium are important for this segment of clinical pathologies. Biological tole - rance (18) depends on the toxicity and on the amount of soluble implant material released. Release, diffusion and washout through blood circulation determine the local concentration of the corrosion products. Alloying components of steel, especially nickel and chromium, are less than optimal in respect to tissue tolerance and allergenicity. Titanium as a pure metal provides excellent biological tolerance (3, 4, 16). Better strength was obtained by titanium alloys like TiAl6V4. The latter found limited application as surgical implants. It

  16. Effects of gold coating on experimental implant fixation

    DEFF Research Database (Denmark)

    Zainali, Kasra; Danscher, Gorm; Jakobsen, Thomas

    2009-01-01

    Insertions of orthopedic implants are traumatic procedures that trigger an inflammatory response. Macrophages have been shown to liberate gold ions from metallic gold. Gold ions are known to act in an antiinflammatory manner by inhibiting cellular NF-kappa B-DNA binding and suppressing I-kappa B......-kinase activation. The present study investigated whether gilding implant Surfaces augmented early implant osseointegration and implant fixation by its modulatory effect on the local inflammatory response. Ion release was traced by autometallographic silver enhancement. Gold-coated cylindrical porous coated Ti6Al4V...

  17. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    OpenAIRE

    Landgraeber, Stefan; Jäger, Marcus; Jacobs, Joshua J.; Hallab, Nadim James

    2014-01-01

    All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older peop...

  18. Influence of Statins locally applied from orthopedic implants on osseous integration

    Directory of Open Access Journals (Sweden)

    Pauly Stephan

    2012-10-01

    Full Text Available Abstract Background Simvastatin increases the expression of bone morphogenetic protein 2 (BMP-2 in osteoblasts, therefore it is important to investigate the influence of statins on bone formation, fracture healing and implant integration. The aim of the present study was to investigate the effect of Simvastatin, locally applied from intramedullary coated and bioactive implants, on bone integration using biomechanical and histomorphometrical analyses. Methods Eighty rats received retrograde nailing of the femur with titanium implants: uncoated vs. polymer-only (poly(D,L-lactide vs. polymer plus drug coated (either Simvastatin low- or high dosed; “SIM low/ high”. Femurs were harvested after 56 days for radiographic and histomorphometric or biomechanical analysis (push-out. Results Radiographic analysis revealed no pathological findings for animals of the control and SIM low dose group. However, n=2/10 animals of the SIM high group showed osteolysis next to the implant without evidence of bacterial infection determined by microbiological analysis. Biomechanical results showed a significant decrease in fixation strength for SIM high coated implants vs. the control groups (uncoated and PDLLA. Histomorphometry revealed a significantly reduced total as well as direct bone/implant contact for SIM high- implants vs. controls (uncoated and PDLLA-groups. Total contact was reduced for SIM low vs. uncoated controls. Significantly reduced new bone formation was measured around SIM high coated implants vs. both control groups. Conclusions This animal study suggests impaired implant integration with local application of Simvastatin from intramedullary titanium implants after 8 weeks when compared to uncoated or carrier-only coated controls.

  19. Wear resistance of laser-deposited boride reinforced Ti-Nb-Zr-Ta alloy composites for orthopedic implants

    International Nuclear Information System (INIS)

    Samuel, Sonia; Nag, Soumya; Scharf, Thomas W.; Banerjee, Rajarshi

    2008-01-01

    The inherently poor wear resistance of titanium alloys limits their application as femoral heads in femoral (hip) implants. Reinforcing the soft matrix of titanium alloys (including new generation β-Ti alloys) with hard ceramic precipitates such as borides offers the possibility of substantially enhancing the wear resistance of these composites. The present study discusses the microstructure and wear resistance of laser-deposited boride reinforced composites based on Ti-Nb-Zr-Ta alloys. These composites have been deposited using the LENS TM process from a blend of elemental Ti, Nb, Zr, Ta, and boron powders and consist of complex borides dispersed in a matrix of β-Ti. The wear resistance of these composites has been compared with that of Ti-6Al-4V ELI, the current material of choice for orthopedic femoral implants, against two types of counterfaces, hard Si 3 N 4 and softer SS440C stainless steel. Results suggest a substantial improvement in the wear resistance of the boride reinforced Ti-Nb-Zr-Ta alloys as compared with Ti-6Al-4V ELI against the softer counterface of SS440. The presence of an oxide layer on the surface of these alloys and composites also appears to have a substantial effect in terms of enhanced wear resistance

  20. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    Directory of Open Access Journals (Sweden)

    Stefan Landgraeber

    2014-01-01

    Full Text Available All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older people (>75 yrs of total joint replacement revision surgery. In some people implant debris (particles and ions from metals can influence the adaptive immune system as well, giving rise to the concept of metal sensitivity. However, a consensus of studies agrees that the dominant form of this response is due to innate reactivity by macrophages to implant debris where both danger (DAMP and pathogen (PAMP signalling elicit cytokine-based inflammatory responses. This paper discusses implant debris induced release of the cytokines and chemokines due to activation of the innate (and the adaptive immune system and the subsequent formation of osteolysis. Different mechanisms of implant-debris reactivity related to the innate immune system are detailed, for example, danger signalling (e.g., IL-1β, IL-18, IL-33, etc., toll-like receptor activation (e.g., IL-6, TNF-α, etc., apoptosis (e.g., caspases 3–9, bone catabolism (e.g., TRAP5b, and hypoxia responses (Hif1-α. Cytokine-based clinical and basic science studies are in progress to provide diagnosis and therapeutic intervention strategies.

  1. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    Science.gov (United States)

    Landgraeber, Stefan; Jäger, Marcus; Jacobs, Joshua J.; Hallab, Nadim James

    2014-01-01

    All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older people (>75 yrs) of total joint replacement revision surgery. In some people implant debris (particles and ions from metals) can influence the adaptive immune system as well, giving rise to the concept of metal sensitivity. However, a consensus of studies agrees that the dominant form of this response is due to innate reactivity by macrophages to implant debris where both danger (DAMP) and pathogen (PAMP) signalling elicit cytokine-based inflammatory responses. This paper discusses implant debris induced release of the cytokines and chemokines due to activation of the innate (and the adaptive) immune system and the subsequent formation of osteolysis. Different mechanisms of implant-debris reactivity related to the innate immune system are detailed, for example, danger signalling (e.g., IL-1β, IL-18, IL-33, etc.), toll-like receptor activation (e.g., IL-6, TNF-α, etc.), apoptosis (e.g., caspases 3–9), bone catabolism (e.g., TRAP5b), and hypoxia responses (Hif1-α). Cytokine-based clinical and basic science studies are in progress to provide diagnosis and therapeutic intervention strategies. PMID:24891761

  2. Effects of orthopedic implants with a polycaprolactone polymer coating containing bone morphogenetic protein-2 on osseointegration in bones of sheep.

    Science.gov (United States)

    Niehaus, Andrew J; Anderson, David E; Samii, Valerie F; Weisbrode, Steven E; Johnson, Jed K; Noon, Mike S; Tomasko, David L; Lannutti, John J

    2009-11-01

    To determine elution characteristics of bone morphogenetic protein (BMP)-2 from a polycaprolactone coating applied to orthopedic implants and determine effects of this coating on osseointegration. 6 sheep. An in vitro study was conducted to determine BMP-2 elution from polycaprolactone-coated implants. An in vivo study was conducted to determine the effects on osseointegration when the polycaprolactone with BMP-2 coating was applied to bone screws. Osseointegration was assessed via radiography, measurement of peak removal torque and bone mineral density, and histomorphometric analysis. Physiologic response was assessed by measuring serum bone-specific alkaline phosphatase activity and uptake of bone markers. Mean +/- SD elution on day 1 of the in vitro study was 263 +/- 152 pg/d, which then maintained a plateau at 59.8 +/- 29.1 pg/d. Mean peak removal torque for screws coated with polycalprolactone and BMP-2 (0.91 +/- 0.65 dN x m) and screws coated with polycaprolactone alone (0.97 +/- 1.30 dN.m) did not differ significantly from that for the control screws (2.34 +/- 1.62 dN x m). Mean bone mineral densities were 0.535 +/- 0.060 g/cm(2), 0.596 +/- 0.093 g/cm(2), and 0.524 +/- 0.142 g/cm(2) for the polycaprolactone-BMP-2-coated, polycaprolactone-coated, and control screws, respectively, and did not differ significantly among groups. Histologically, bone was in closer apposition to the implant with the control screws than with either of the coated screws. BMP-2 within the polycaprolactone coating did not stimulate osteogenesis. The polycaprolactone coating appeared to cause a barrier effect that prevented formation of new bone. A longer period or use of another carrier polymer may result in increased osseointegration.

  3. Ica-expression and gentamicin susceptibility of Staphylococcus epidermidis biofilm on orthopedic implant biomaterials

    NARCIS (Netherlands)

    Nuryastuti, Titik; Krom, Bastiaan P.; Aman, Abu T.; Busscher, Henk J.; van der Mei, Henny C.

    Ica-expression by Staphylococcus epidermidis and slime production depends on environmental conditions such as implant material and presence of antibiotics. Here, we evaluate biofilm formation and ica-expression of S. epidermidis strains on biomaterials involved in total hip-and knee arthroplasty

  4. Performances of low-dose dual-energy CT in reducing artifacts from implanted metallic orthopedic devices

    Energy Technology Data Exchange (ETDEWEB)

    Filograna, Laura [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Institute of Radiology, Rome (Italy); University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland); Magarelli, Nicola; Leone, Antonio; Bonomo, Lorenzo [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Institute of Radiology, Rome (Italy); De Waure, Chiara; Calabro, Giovanna Elisa [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Research Centre for Health Technology Assessment, Department of Public Health, Section of Hygiene, Rome (Italy); Finkenstaedt, Tim [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Thali, Michael John [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland)

    2016-07-15

    The objective was to evaluate the performances of dose-reduced dual-energy computed tomography (DECT) in decreasing metallic artifacts from orthopedic devices compared with dose-neutral DECT, dose-neutral single-energy computed tomography (SECT), and dose-reduced SECT. Thirty implants in 20 consecutive cadavers underwent both SECT and DECT at three fixed CT dose indexes (CTDI): 20.0, 10.0, and 5.0 mGy. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV, and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. In each group, the image quality of the seven monoenergetic images and of the SECT image was assessed qualitatively and quantitatively by visually rating and by measuring the maximum streak artifact respectively. The comparison between SECT and OPTkeV evaluated overall within all groups showed a significant difference (p <0.001), with OPTkeV images providing better images. Comparing OPTkeV with the other DECT images, a significant difference was shown (p <0.001), with OPTkeV and 130-keV images providing the qualitatively best results. The OPTkeV images of 5.0-mGy acquisitions provided percentages of images with scores 1 and 2 of 36 % and 30 % respectively, compared with 0 % and 33.3 % of the corresponding SECT images of 10- and 20-mGy acquisitions. Moreover, DECT reconstructions at the OPTkeV of the low-dose group showed higher CT numbers than the SECT images of dose groups 1 and 2. This study demonstrates that low-dose DECT permits a reduction of artifacts due to metallic implants to be obtained in a similar manner to neutral-dose DECT and better than reduced or neutral-dose SECT. (orig.)

  5. TiZrNbTaMo high-entropy alloy designed for orthopedic implants: As-cast microstructure and mechanical properties.

    Science.gov (United States)

    Wang, Shao-Ping; Xu, Jian

    2017-04-01

    Combining the high-entropy alloy (HEA) concept with property requirement for orthopedic implants, we designed a Ti 20 Zr 20 Nb 20 Ta 20 Mo 20 equiatomic HEA. The arc-melted microstructures, compressive properties and potentiodynamic polarization behavior in phosphate buffer solution (PBS) were studied in detail. It was revealed that the as-cast TiZrNbTaMo HEA consisted of dual phases with bcc structure, major bcc1 and minor bcc2 phases with the lattice parameters of 0.3310nm and 0.3379nm, respectively. As confirmed by nanoindentation tests, the bcc1 phase is somewhat harder and stiffer than the bcc2 phase. The TiZrNbTaMo HEA exhibited Young's modulus of 153GPa, Vickers microhardness of 4.9GPa, compressive yield strength of σ y =1390MPa and apparent plastic strain of ε p ≈6% prior to failure. Moreover, the TiZrNbTaMo HEA manifested excellent corrosion resistance in PBS, comparable to the Ti6Al4V alloy, and pitting resistance remarkably superior to the 316L SS and CoCrMo alloys. These preliminary advantages of the TiZrNbTaMo HEA over the current orthopedic implant metals in mechanical properties and corrosion resistance offer an opportunity to explore new orthopedic-implant alloys based on the TiZrNbTaMo concentrated composition. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Activation of human leukocytes on tantalum trabecular metal in comparison to commonly used orthopedic metal implant materials.

    Science.gov (United States)

    Schildhauer, T A; Peter, E; Muhr, G; Köller, M

    2009-02-01

    We analyzed leukocyte functions and cytokine response of human leukocytes toward porous tantalum foam biomaterial (Trabecular Metaltrade mark, TM) in comparison to equally sized solid orthopedic metal implant materials (pure titanium, titanium alloy, stainless steel, pure tantalum, and tantalum coated stainless steel). Isolated peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) were cocultured with equally sized metallic test discs for 24 h. Supernatants were analyzed for cytokine content by enzyme-linked immunosorbent assay. Compared to the other used test materials there was a significant increase in the release of IL (interleukin)-1ra and IL-8 from PMN, and of IL-1ra, IL-6, and TNF-alpha from PBMC in response to the TM material. The cytokine release correlated with surface roughness of the materials. In contrast, the release of IL-2 was not induced showing that mainly myeloid leukocytes were activated. In addition, supernatants of these leukocyte/material interaction (conditioned media, CM) were subjected to whole blood cell function assays (phagocytosis, chemotaxis, bacterial killing). There was a significant increase in the phagocytotic capacity of leukocytes in the presence of TM-conditioned media. The chemotactic response of leukocytes toward TM-conditioned media was significantly higher compared to CM obtained from other test materials. Furthermore, the bactericidal capacity of whole blood was enhanced in the presence of TM-conditioned media. These results indicate that leukocyte activation at the surface of TM material induces a microenvironment, which may enhance local host defense mechanisms.

  7. Corrosion resistance and in vitro response of laser-deposited Ti-Nb-Zr-Ta alloys for orthopedic implant applications.

    Science.gov (United States)

    Samuel, Sonia; Nag, Soumya; Nasrazadani, Seifollah; Ukirde, Vaishali; El Bouanani, Mohamed; Mohandas, Arunesh; Nguyen, Kytai; Banerjee, Rajarshi

    2010-09-15

    While direct metal deposition of metallic powders, via laser deposition, to form near-net shape orthopedic implants is an upcoming and highly promising technology, the corrosion resistance and biocompatibility of such novel metallic biomaterials is relatively unknown and warrants careful investigation. This article presents the results of some initial studies on the corrosion resistance and in vitro response of laser-deposited Ti-Nb-Zr-Ta alloys. These new generation beta titanium alloys are promising due to their low elastic modulus as well as due the fact that they comprise of completely biocompatible alloying elements. The results indicate that the corrosion resistance of these laser-deposited alloys is comparable and in some cases even better than the currently used commercially-pure (CP) titanium (Grade 2) and Ti-6Al-4V ELI alloys. The in vitro studies indicate that the Ti-Nb-Zr-Ta alloys exhibit comparable cell proliferation but enhanced cell differentiation properties as compared with Ti-6Al-4V ELI. (c) 2010 Wiley Periodicals, Inc.

  8. Molecular characterization of a prevalent ribocluster of methicillin-sensitiveStaphylococcus aureus from orthopedic implant infections. Correspondencewith MLST CC30

    Directory of Open Access Journals (Sweden)

    Lucio eMontanaro

    2016-02-01

    Full Text Available ABSTRACTStaphylococcus aureus is the leading etiologic agent of orthopedic implant infections. Here a ribocluster of 27 S. aureus strains underwent further molecular characterization and subtyping by multilocus sequence typing (MLST and spa-typing. This cluster had been detected by automated ribotyping (with EcoRI as restriction enzyme of 200 S. aureus isolates from periprosthetic infections come for revision at the Rizzoli Orthopaedic Institute. The ribocluster, consisting of agr type III isolates, with a 74% co-presence of bone sialoprotein-binding (bbp and collagen-binding (cna genes, turned out devoid of mecA and IS256 and exhibited a high prevalence of toxic shock syndrome toxin gene (tst, 85%. Sequences achieved by spa typing and MLST were analyzed by BURP and goeBURST. Two predominant spa types, t012 (32% and t021 (36%, and one predominant sequence type, ST30 (18/27, 67%, a Staphylococcus aureus lineage spread worldwide and regarded as the ancestor of MLST CC30, were identified. Two new sequence types (ST2954, ST2960 and one new spa type (t13129 were detected for the first time. BURP clustered the isolates into two spa clonal complexes, CC021/012 (22/27, 81% and CC166 (4/27, 15%, plus one singleton, while goeBURST recognized solely MLST CC30. Interestingly, the 27-strains cluster detected by ribotyping corresponded exactly to CC30.

  9. The promising application of graphene oxide as coating materials in orthopedic implants: preparation, characterization and cell behavior

    International Nuclear Information System (INIS)

    Zhao, Changhong; Lu, Xiuzhen; Liu, Johan; Zanden, Carl

    2015-01-01

    To investigate the potential application of graphene oxide (GO) in bone repair, this study is focused on the preparation, characterization and cell behavior of graphene oxide coatings on quartz substrata. GO coatings were prepared on the substrata using a modified dip-coating procedure. Atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman spectroscopy results demonstrated that the as-prepared coatings in this study were homogeneous and had an average thickness of ∼67 nm. The rapid formation of a hydroxyapatite (HA) layer in the simulated body fluid (SBF) on GO coated substrata at day 14, as proved by SEM and x-ray diffraction (XRD), strongly indicated the bioactivity of coated substrata. In addition, MC3T3-E1 cells were cultured on the coated substrata to evaluate cellular activities. Compared with the non-coated substrata and tissue culture plates, no significant difference was observed on the coated substrata in terms of cytotoxicity, viability, proliferation and apoptosis. However, interestingly, higher levels of alkaline phosphatase (ALP) activity and osteocalcin (OC) secretion were observed on the coated substrata, indicating that GO coatings enhanced cell differentiation compared with non-coated substrata and tissue culture plates. This study suggests that GO coatings had excellent biocompatibility and more importantly promoted MC3T3-E1 cell differentiation and might be a good candidate as a coating material for orthopedic implants. (paper)

  10. Implant healing in experimental animal models of diabetes.

    Science.gov (United States)

    Le, Nga N; Rose, Michael B; Levinson, Howard; Klitzman, Bruce

    2011-05-01

    Diabetes mellitus is becoming increasingly prevalent worldwide. Additionally, there is an increasing number of patients receiving implantable devices such as glucose sensors and orthopedic implants. Thus, it is likely that the number of diabetic patients receiving these devices will also increase. Even though implantable medical devices are considered biocompatible by the Food and Drug Administration, the adverse tissue healing that occurs adjacent to these foreign objects is a leading cause of their failure. This foreign body response leads to fibrosis, encapsulation of the device, and a reduction or cessation of device performance. A second adverse event is microbial infection of implanted devices, which can lead to persistent local and systemic infections and also exacerbates the fibrotic response. Nearly half of all nosocomial infections are associated with the presence of an indwelling medical device. Events associated with both the foreign body response and implant infection can necessitate device removal and may lead to amputation, which is associated with significant morbidity and cost. Diabetes mellitus is generally indicated as a risk factor for the infection of a variety of implants such as prosthetic joints, pacemakers, implantable cardioverter defibrillators, penile implants, and urinary catheters. Implant infection rates in diabetic patients vary depending upon the implant and the microorganism, however, for example, diabetes was found to be a significant variable associated with a nearly 7.2% infection rate for implantable cardioverter defibrillators by the microorganism Candida albicans. While research has elucidated many of the altered mechanisms of diabetic cutaneous wound healing, the internal healing adjacent to indwelling medical devices in a diabetic model has rarely been studied. Understanding this healing process is crucial to facilitating improved device design. The purpose of this article is to summarize the physiologic factors that

  11. Carbon-carbon composites for orthopedic prosthesis and implants. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T D; Klett, J W; Strizak, J P [Oak Ridge National Lab., TN (United States); Baker, C [FMI, Biddeford, ME (United States)

    1998-01-21

    The prosthetic implant market is extensive. For example, because of arthritic degeneration of hip and knee cartilage and osteoporotic fractures of the hip, over 200,000 total joint replacements (TJRs) are performed in the United States each year. Current TJR devices are typically metallic (stainless steel, cobalt, or titanium alloy) and are fixed in the bone with polymethylacrylate (PMMA) cement. Carbon-carbon composite materials offer several distinct advantages over metals for TJR prosthesis. Their mechanical properties can be tailored to match more closely the mechanical properties of human bone, and the composite may have up to 25% porosity, the size and distribution of which may be controlled through processing. The porous nature of carbon-carbon composites will allow for the ingrowth of bone, achieving biological fixation, and eliminating the need for PMMA cement fixation.

  12. Wear and damage of articular cartilage with friction against orthopedic implant materials.

    Science.gov (United States)

    Oungoulian, Sevan R; Durney, Krista M; Jones, Brian K; Ahmad, Christopher S; Hung, Clark T; Ateshian, Gerard A

    2015-07-16

    The objective of this study was to measure the wear response of immature bovine articular cartilage tested against glass or alloys used in hemiarthroplasties. Two cobalt chromium alloys and a stainless steel alloy were selected for these investigations. The surface roughness of one of the cobalt chromium alloys was also varied within the range considered acceptable by regulatory agencies. Cartilage disks were tested in a configuration that promoted loss of interstitial fluid pressurization to accelerate conditions believed to occur in hemiarthroplasties. Results showed that considerably more damage occurred in cartilage samples tested against stainless steel (10 nm roughness) and low carbon cobalt chromium alloy (27 nm roughness) compared to glass (10 nm) and smoother low or high carbon cobalt chromium (10 nm). The two materials producing the greatest damage also exhibited higher equilibrium friction coefficients. Cartilage damage occurred primarily in the form of delamination at the interface between the superficial tangential zone and the transitional middle zone, with much less evidence of abrasive wear at the articular surface. These results suggest that cartilage damage from frictional loading occurs as a result of subsurface fatigue failure leading to the delamination. Surface chemistry and surface roughness of implant materials can have a significant influence on tissue damage, even when using materials and roughness values that satisfy regulatory requirements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Risk assessment of electromagnetic fields exposure with metallic orthopedic implants: a cadaveric study.

    Science.gov (United States)

    Crouzier, D; Selek, L; Martz, B-A; Dabouis, V; Arnaud, R; Debouzy, J-C

    2012-02-01

    Metallic materials are well known to strongly interact with electromagnetic fields. While biological effects of such field have been extensively studied, only few works dealt with the interactions of electromagnetic waves with passive metallic device implanted in biological system. Hence only several numerical and phantom simulation studies were focusing on this aspect, whereas no in situ anatomic experiment has been previously performed. In this study the effect of electromagnetic waves on eight different orthopaedic medical devices (six plates from 55 to 318mm length, a total knee and a total hip prosthesis) were explored on six human cadavers. To mimic a random environmental exposure resulting from the most common frequencies band used in domestic environment and medical applications (TV and radio broadcasting, cell phone communication, MRI, diathermy treatment), a multifrequency generator emitting in VHF, UHF, GSM and GCS frequency bands was used. The different medical devices were exposed to an electromagnetic field at 50W/m(2) and 100W/m(2). After 6min exposure, the temperature was measured on three points close to each medical device, and the induced currents were estimated. No significant temperature increase (<0.2°C) was finally detected; beside, a slight induced tension (up to 1.1V) was recorded but would appear too low to induce any biological side effect. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  14. Applied biomechanics to evaluate the properties of laser beam treated orthopedic implants

    International Nuclear Information System (INIS)

    Pieretti, Eurico Felix

    2016-01-01

    Laser beam marking is used to ensure biomaterials’ identification and traceability. The texturing imparts greater adhesion to the surfaces of implantable medical devices. The aim of this work was to evaluate the surface behaviour of the austenitic stainless steel ABNT NBR ISO 5832-1 marked and textured by optical fiber laser beam using selected parameters, changing the pulse frequency; in face of its biomechanical behaviour, through tests of tensile strength, fatigue and wear; verify the localized corrosion susceptibility by electrochemical tests in a solution that simulates the body fluids; and analyze microstructural changes. The treatments performed altered the biomaterials roughness and their micro hardness as a function of the increase of the pulse frequency. The microstructure and chemical composition of the surfaces underwent changes that directly affected the passive layer of the stainless steels, triggering the corrosion process. This effect was evidenced by SVET, XPS and characterization of electronic properties of the passive film by the Mott-Schottky technique. These two types of laser treatments increased the surfaces' magnetic susceptibility. The parameters used for the marking and texturing did not induce a decrease in the cellular viability of the samples, as no cytotoxicity was showed even after prolonged incubation. This biomaterial was adequate on the biomechanical tests, since the laser treatments, under the conditions used, did not induce the formation of surface tensions of magnitude capable of leading the fatigue fracture, indicating infinite fatigue life; the region of fracture by tension could not be related to the laser marking. The wear volume decreased as a function of the increase in micro hardness produced by the increase of the pulse frequency in the texturing. The visual character of the markings and texturing was assured after the majority of the tests performed. (author)

  15. Influence of Si addition on the microstructure and mechanical properties of Ti-35Nb alloy for applications in orthopedic implants.

    Science.gov (United States)

    Tavares, A M G; Ramos, W S; de Blas, J C G; Lopes, E S N; Caram, R; Batista, W W; Souza, S A

    2015-11-01

    In the development of new materials for orthopedic implants, special attention has been given to Ti alloys that show biocompatible alloy elements and that are capable of reducing the elastic modulus. Accordingly, Ti-Nb-Si alloys show great potential for application. Thus, this is a study on the microstructures and properties of Ti-35Nb-xSi alloys (x=0, 0.15, 0.35 and 0.55) (wt%) which were thermally treated and cooled under the following conditions: furnace cooling (FC), air cooling (AC), and water quenching (WQ). The results showed that Si addition is effective to reduce the density of omega precipitates making beta more stable, and to produce grain refinement. Silicides, referred as (Ti,Nb)3Si, were formed for alloys containing 0.55% Si, and its formation presumably occurred during the heating at 1000°C. In all cooling conditions, the hardness values increased with the increasing of Si content, as a result from the strong Si solid solution strengthening effect, while the elastic modulus underwent a continuous reduction due to the reduction of omega precipitates in beta matrix. Lower elastic moduli were observed in water-quenched alloys, which concentration of 0.15% Si was more effective in their reduction, with value around 65 GPa. Regarding Ti-35Nb-xSi alloys (x=0, 0.15 and 0.35), the "double yield point" phenomenon, which is typical of alloys with shape memory effect, was observed. The increase in Si concentration also produced an increase from 382 MPa to 540 MPa in the alloys' mechanical strength. Ti-35Nb-0.55Si alloy, however, showed brittle mechanical behavior which was related to the presence of silicides at the grain boundary. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Gentamicin-loaded poly(lactic-co-glycolic acid) microparticles for the prevention of maxillofacial and orthopedic implant infections

    International Nuclear Information System (INIS)

    Flores, Claudia; Degoutin, Stephanie; Chai, Feng; Raoul, Gwenael; Hornez, Jean-Chritophe; Martel, Bernard; Siepmann, Juergen; Ferri, Joel; Blanchemain, Nicolas

    2016-01-01

    Trauma and orthopedic surgery can cause infections as any open surgical procedures. Such complications occur in only1 to 5% of the cases, but the treatment is rather complicated due to bacterial biofilm formation and limited drug access to the site of infection upon systemic administration. An interesting strategy to overcome this type of complications is to prevent bacterial proliferation and biofilm formation via the local and controlled release of antibiotic drugs from the implant itself. Obviously, the incorporation of the drug into the implant should not affect the latter's biological and mechanical properties. In this context, we optimized the preparation process for gentamicin-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles, which can be incorporated in the macropores of calcium phosphate-based bone substitutes. Microparticles were prepared using a double emulsion solvent extraction/evaporation technique. The processing parameters were optimized in order to provide an average microparticle size of about 60 μm, allowing for incorporation inside the macropores (100 μm) of the hydroxyapatite scaffold. Gentamicin-loaded PLGA microparticles showed a sustained release for 25–30 days and a rapid antibacterial activity due to a burst effect, the extent of which was controlled by the initial loading of the microparticles. SEM pictures revealed a highly porous microparticle structure, which can help to reduce the micro environmental pH drop and autocatalytic effects. The biological evaluation showed the cytocompatibility and non-hemolytic property of the microparticles, and the antibacterial activity against Staphylococcus aureus under the given conditions. - Highlights: • The optimization of microparticle preparation parameters allows to obtain a size compatible with the bone substitute porosity • PDL% has a direct impact on the burst effect, a control release of gentamicin was obtained • The incorporation of microparticles into the macroporosity

  17. Gentamicin-loaded poly(lactic-co-glycolic acid) microparticles for the prevention of maxillofacial and orthopedic implant infections

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Claudia [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France); Degoutin, Stephanie [Univ. Lille, 59000 Lille (France); UMET, Ingénierie des Systèmes Polymères, Université de Lille 1, 59655 Villeneuve d' Ascq (France); Chai, Feng [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France); Raoul, Gwenael [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France); Service Chirurgie Maxillo-Faciale, CHRU de Lille, 59000 Lille (France); Hornez, Jean-Chritophe [Laboratoire des Matériaux Céramiques et Procédés Associés (LMCPA), Université de Valenciennes, 59300 Valenciennes (France); Martel, Bernard [Univ. Lille, 59000 Lille (France); UMET, Ingénierie des Systèmes Polymères, Université de Lille 1, 59655 Villeneuve d' Ascq (France); Siepmann, Juergen [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France); Ferri, Joel [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France); Service Chirurgie Maxillo-Faciale, CHRU de Lille, 59000 Lille (France); Blanchemain, Nicolas, E-mail: nicolas.blanchemain@univ-lille2.fr [Univ. Lille, 59000 Lille (France); INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, 59000 Lille (France)

    2016-07-01

    Trauma and orthopedic surgery can cause infections as any open surgical procedures. Such complications occur in only1 to 5% of the cases, but the treatment is rather complicated due to bacterial biofilm formation and limited drug access to the site of infection upon systemic administration. An interesting strategy to overcome this type of complications is to prevent bacterial proliferation and biofilm formation via the local and controlled release of antibiotic drugs from the implant itself. Obviously, the incorporation of the drug into the implant should not affect the latter's biological and mechanical properties. In this context, we optimized the preparation process for gentamicin-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles, which can be incorporated in the macropores of calcium phosphate-based bone substitutes. Microparticles were prepared using a double emulsion solvent extraction/evaporation technique. The processing parameters were optimized in order to provide an average microparticle size of about 60 μm, allowing for incorporation inside the macropores (100 μm) of the hydroxyapatite scaffold. Gentamicin-loaded PLGA microparticles showed a sustained release for 25–30 days and a rapid antibacterial activity due to a burst effect, the extent of which was controlled by the initial loading of the microparticles. SEM pictures revealed a highly porous microparticle structure, which can help to reduce the micro environmental pH drop and autocatalytic effects. The biological evaluation showed the cytocompatibility and non-hemolytic property of the microparticles, and the antibacterial activity against Staphylococcus aureus under the given conditions. - Highlights: • The optimization of microparticle preparation parameters allows to obtain a size compatible with the bone substitute porosity • PDL% has a direct impact on the burst effect, a control release of gentamicin was obtained • The incorporation of microparticles into the

  18. New Ti-Alloys and Surface Modifications to Improve the Mechanical Properties and the Biological Response to Orthopedic and Dental Implants: A Review

    Science.gov (United States)

    Kirmanidou, Yvoni; Sidira, Margarita; Drosou, Maria-Eleni; Bennani, Vincent; Bakopoulou, Athina; Tsouknidas, Alexander; Michailidis, Nikolaos; Michalakis, Konstantinos

    2016-01-01

    Titanium implants are widely used in the orthopedic and dentistry fields for many decades, for joint arthroplasties, spinal and maxillofacial reconstructions, and dental prostheses. However, despite the quite satisfactory survival rates failures still exist. New Ti-alloys and surface treatments have been developed, in an attempt to overcome those failures. This review provides information about new Ti-alloys that provide better mechanical properties to the implants, such as superelasticity, mechanical strength, and corrosion resistance. Furthermore, in vitro and in vivo studies, which investigate the biocompatibility and cytotoxicity of these new biomaterials, are introduced. In addition, data regarding the bioactivity of new surface treatments and surface topographies on Ti-implants is provided. The aim of this paper is to discuss the current trends, advantages, and disadvantages of new titanium-based biomaterials, fabricated to enhance the quality of life of many patients around the world. PMID:26885506

  19. A novel co-culture model of murine K12 osteosarcoma cells and S. aureus on common orthopedic implant materials: 'the race to the surface' studied in vitro.

    Science.gov (United States)

    McConda, David B; Karnes, Jonathan M; Hamza, Therwa; Lindsey, Brock A

    2016-07-01

    Infection is a major cause of orthopedic implant failure. There are few studies assessing both tissue cell and bacterial adherence on common orthopedic implant materials in a co-culture environment. An in vitro co-culture model was created using K12 osteosarcoma cells and Staphylococcus aureus in a medium incubated over metal disks for 48 h. The results showed that, in the presence of S. aureus, there were fewer osteosarcoma cells attached to the disks for all substrata tested. There were significantly more osteosarcoma cells adhering to the cobalt chrome than the stainless steel and titanium disks. Overall, in the presence of osteosarcoma cells, there were more bacteria adhering to the disks for all the substrata tested, with significantly more bacteria adhering to the stainless steel disks compared to cobalt chrome and titanium disks. Scanning electron microscopy verified that osteosarcoma cells and bacteria were adherent to the metal disks after incubation for 48 h. Furthermore, the observation that more bacteria were in the co-culture than in the control sample suggests that the osteosarcoma cells serve as a nutrient source for the bacteria. Future models assessing the interaction of osteogenic cells with bacteria on a substratum would be improved if the model accounted for the role of the immune system in secondary bone healing.

  20. Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants

    Czech Academy of Sciences Publication Activity Database

    Stráský, J.; Havlíková, Jana; Bačáková, Lucie; Harcuba, P.; Mhaede, M.; Janeček, M.

    2013-01-01

    Roč. 213, Sep 15 (2013), s. 73-78 ISSN 0169-4332 R&D Projects: GA ČR(CZ) GAP107/12/1025 Institutional support: RVO:67985823 Keywords : Ti-6A1-4V * surface treatment * cell proliferation * orthopedics Subject RIV: JG - Metallurgy Impact factor: 2.538, year: 2013

  1. Angulated Dental Implants in Posterior Maxilla FEA and Experimental Verification

    Directory of Open Access Journals (Sweden)

    Hamed A. Hamed

    2018-02-01

    Full Text Available AIM: This study aimed to evaluate the effect of different implant angulations in posterior maxilla on stress distribution by finite element analysis and verify its results experimentally. METHODS: Two simplified models were prepared for an implant placed vertically and tilted 25° piercing the maxillary sinus. Geometric models' components were prepared by Autodesk Inventor then assembled in ANSYS for finite element analysis. The results of finite element analysis were verified against experimental trials results which were statistically analysed using student t-test (level of significance p < 0.05. RESULTS: Implant - abutment complex absorbed the load energy in case of vertical implant better than the case of angulated one. That was reflected on cortical bone stress, while both cases showed stress levels within the physiological limits. Comparing results between FEA and experiment trials showed full agreement. CONCLUSION: It was found that the tilted implant by 25° can be utilised in the posterior region maxilla for replacing maxillary first molar avoiding sinus penetration. The implant-bone interface and peri-implant bones received the highest Von Mises stress. Implant - bone interface with angulated implant received about 66% more stresses than the straight one.

  2. Microbiota in experimental periodontitis and peri-implantitis in dogs.

    Science.gov (United States)

    Charalampakis, Georgios; Abrahamsson, Ingemar; Carcuac, Olivier; Dahlén, Gunnar; Berglundh, Tord

    2014-09-01

    To analyze the microbial profile around teeth and implants following ligature removal in experimental periodontitis and peri-implantitis in dogs. Four implants with similar geometry and with two different surface characteristics (implant A: turned/implant B: TiUnite; NobelBiocare AB) were placed pairwise in the right side of the mandible 3 months after tooth extraction in five dogs. Experimental periodontitis and peri-implantitis were initiated 3 months later by ligature placement around implants and mandibular premolars and plaque formation. The ligatures were removed after 10 weeks. Microbial samples were obtained using paper points immediately after ligature removal, at 10 and 25 weeks after ligature removal. The microbiological analysis was performed by "checkerboard" DNA-DNA hybridization, including a panel of 16 bacterial species. The amount of bone loss that occurred during the period following ligature removal was significantly larger at implants with a modified surface than at implants with a turned surface and at teeth. The microbiological analysis revealed that the total bacterial load increased during the period following ligature removal and established an anaerobic Gram-negative microflora. It is suggested that the large variation in regard to the microbial profiles makes interpretation of a correlation between disease progression and microbial profiles difficult. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Angulated Dental Implants in Posterior Maxilla FEA and Experimental Verification.

    Science.gov (United States)

    Hamed, Hamed A; Marzook, Hamdy A; Ghoneem, Nahed E; El-Anwar, Mohamed I

    2018-02-15

    This study aimed to evaluate the effect of different implant angulations in posterior maxilla on stress distribution by finite element analysis and verify its results experimentally. Two simplified models were prepared for an implant placed vertically and tilted 25° piercing the maxillary sinus. Geometric models' components were prepared by Autodesk Inventor then assembled in ANSYS for finite element analysis. The results of finite element analysis were verified against experimental trials results which were statistically analysed using student t-test (level of significance p < 0.05). Implant - abutment complex absorbed the load energy in case of vertical implant better than the case of angulated one. That was reflected on cortical bone stress, while both cases showed stress levels within the physiological limits. Comparing results between FEA and experiment trials showed full agreement. It was found that the tilted implant by 25° can be utilised in the posterior region maxilla for replacing maxillary first molar avoiding sinus penetration. The implant-bone interface and peri-implant bones received the highest Von Mises stress. Implant - bone interface with angulated implant received about 66% more stresses than the straight one.

  4. Improvements of anti-corrosion and mechanical properties of NiTi orthopedic materials by acetylene, nitrogen and oxygen plasma immersion ion implantation

    International Nuclear Information System (INIS)

    Poon, Ray W.Y.; Ho, Joan P.Y.; Liu Xuanyong; Chung, C.Y.; Chu, Paul K.; Yeung, Kelvin W.K.; Lu, William W.; Cheung, Kenneth M.C.

    2005-01-01

    Nickel-titanium shape memory alloys (NiTi) are useful materials in orthopedics and orthodontics due to their unique super-elasticity and shape memory effects. However, the problem associated with the release of harmful Ni ions to human tissues and fluids has been raising safety concern. Hence, it is necessary to produce a surface barrier to impede the out-diffusion of Ni ions from the materials. We have conducted acetylene, nitrogen and oxygen plasma immersion ion implantation (PIII) into NiTi alloys in an attempt to improve the surface properties. All the implanted and annealed samples surfaces exhibit outstanding corrosion and Ni out-diffusion resistance. Besides, the implanted layers are mechanically stronger than the substrate underneath. XPS analyses disclose that the layer formed by C 2 H 2 PIII is composed of mainly TiC x with increasing Ti to C concentration ratios towards the bulk. The nitrogen PIII layer is observed to be TiN, whereas the oxygen PIII layer is composed of oxides of Ti 4+ , Ti 3+ and Ti 2+

  5. A study of calcium carbonate/multiwalled-carbon nanotubes/chitosan composite coatings on Ti–6Al–4V alloy for orthopedic implants

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Rasha A., E-mail: rashaauf@yahoo.com [Chemistry Department, Faculty of Science, Taif University (Saudi Arabia); Forensic Chemistry Laboratories, Medico Legal Department, Ministry of Justice, Cairo (Egypt); Fekry, Amany M. [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt); Farghali, R.A. [Chemistry Department, Faculty of Science, Taif University (Saudi Arabia); Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2013-11-15

    In an attempt to increase the stability, bioactivity and corrosion resistance of Ti–6Al–4V alloy, chitosan (CS) biocomposite coatings reinforced with multiwalled-carbon nanotubes (MWCNTs), and calcium carbonate (CaCO{sub 3}) for surface modification were utilized by electroless deposition. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) reveals the formation of a compact and highly crosslinked coatings. Electrochemical techniques were used to investigate the coats stability and resistivity for orthopedic implants in simulated body fluid (SBF). The results show that E{sub st} value is more positive in the following order: CaCO{sub 3}/MWCNTs/CS > CS/MWCNTs > CS > MWCNTs. The calculated i{sub corr} was 0.02 nA cm{sup −2} for CaCO{sub 3}/MWCNTs/CS which suggested a high corrosion resistance.

  6. Surgical site infection in orthopedic implants and its common bacteria with their sensitivities to antibiotics, in open reduction internal fixation

    International Nuclear Information System (INIS)

    Shah, M.Q.; Zardad, M.S.; Khan, A.; Ahmed, S.; Awan, A. S.; Mohammad, T.

    2017-01-01

    Surgical site infection in orthopaedic implants is a major problem, causing long hospital stay, cost to the patient and is a burden on health care facilities. It increases rate of non-union, osteomyelitis, implant failure, sepsis, multiorgan dysfunction and even death. Surgical site infection is defined as pain, erythema, swelling and discharge from wound site. Surgical site infection in orthopaedic implants is more challenging to the treating orthopaedic surgeon as the causative organism is protected by a biofilm over the implant's surface. Antibiotics cannot cross this film to reach the bacteria's, causing infection. Method: This descriptive case series study includes 132 patients of both genders with ages between 13 years to 60 years conducted at Orthopaedic Unit, Ayub Medical College, Abbottabad from 1st October 2015 to 31st March 2016. Patients with close fractures of long bones were included in the study to determine the frequency of surgical site infection in orthopaedic implants and the type of bacteria involved and their sensitivity to various antibiotics. All implants were of stainless steel. The implants used were Dynamic hip screws, Dynamic compression screws, plates, k-wires, Interlocking nails, SIGN nails, Austin Moore prosthesis and tension band wires. Pre-op and post-op antibiotics used were combination of Sulbactum and Cefoperazone which was given 1 hour before surgery and continued for 72 hours after surgery. Patients were followed up to 4 weeks. Pus was taken on culture stick, from those who developed infection. Results were entered in the pro forma. Results: A total of 132 patients of long bone fractures, who were treated with open reduction and internal fixation, were studied. Only 7 patients developed infection. Staphylococcus Aureus was isolated from all 7 patients. Staphylococcus aureus was sensitive to Linezolid, Fusidic Acid, and vancomycin. Cotrimoxazole, tetracycline, Gentamycin and Clindamycin were partially effective. Conclusion

  7. In vitro and in vivo biocompatibility and osteogenesis of graphene-reinforced nanohydroxyapatite polyamide66 ternary biocomposite as orthopedic implant material

    Directory of Open Access Journals (Sweden)

    Zhang S

    2016-07-01

    bone screws were implanted in canine femoral condyles, and postoperative histology revealed no obvious damage to the liver, spleen, kidneys, brain, or other major organs. The bone tissue around the implant grew well and was directly connected to the implant. The soft tissues showed no obvious inflammatory reaction, which demonstrated the good biocompatibility of the screws. These observations indicate that graphene-reinforced nHA/PA66 composites have great potential for application in bone tissue engineering. Keywords: graphene, orthopedic biomaterials, cell differentiation, stem cells, bone tissue engineering 

  8. Reposição cirúrgico-ortopédica de implante mal posicionado: relato de caso Surgical-orthopedic repositioning of malpositioned implant: a case report

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Ferreira da Silva

    2005-06-01

    Full Text Available A reabilitação bucal por meio da colocação de implantes dentários tem se tornado um procedimento freqüente da clínica odontológica. Falhas no planejamento ou na execução da técnica podem levar a casos onde, apesar de osseointegrado, o implante não apresenta condições de restauração satisfatória devido ao seu mal posicionamento. Diversos autores têm relatado a possibilidade de se utilizar osteotomias segmentares de maxila ou mandíbula para reposicionar um segmento alveolar com implante, mostrando que esta pode ser uma técnica efetiva e previsível para restaurar implantes em posição anatômica comprometida. O presente trabalho apresenta o caso clínico de uma paciente de 20 anos de idade onde foi realizada osteotomia segmentar de maxila associada à distração osteogênica para correção de um implante mal posicionado.Oral rehabilitation through dental implants has become a common procedure at dental practice. However, if the implant is placed in an inappropriate position either because of inadequate presurgical planning or poor surgical technique, it may be unrestorable in spite of osseointegrated. Many authors have reported the possibility of using segmental maxillary or mandibular osteotomies to reposition an alveolar segment with its implants. This can be an effective, predictable technique for restoring implants in a compromised anatomic position. This paper presents a case report describing the use of this procedure associated to distraction osteogeneis to reposition one malpositioned implant in a 20 years old girl.

  9. Evaluation of bone loss in antibacterial coated dental implants: An experimental study in dogs

    DEFF Research Database (Denmark)

    Gallardo, Maria Godoy; Manzanares-Céspedes, Maria Cristina; Sevilla, Pablo

    2016-01-01

    _Ag (silver electrodeposition treatment, 10 units), and Ti_TSP (silanization treatment, 10 units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated...

  10. Bone reactions at implants subjected to experimental peri-implantitis and static load. A study in the dog

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2002-01-01

    during a 12-week interval, the screws were reactivated. Thus, the model included 3 different experimental sites of each surface group: group M+L (mucositis+load); group P (peri-implantitis); group P+L (peri-implantitis+load). Fluorochrome labels were injected and standardized radiographs obtained....... The animals were sacrificed and block biopsies of all implant sites dissected and prepared for histological analysis. RESULTS: It was demonstrated that the lateral static load failed to induce peri-implant bone loss at implants with mucositis and failed to enhance the bone loss at implants with experimental...... peri-implantitis. The proportion of bone labels and the bone density in the interface zone were significantly higher in group P+L than in group P. CONCLUSION: It is suggested that a lateral static load with controlled forces may not be detrimental to implants exhibiting mucositis or peri-implantitis....

  11. Strategies for achieving orthopedic service line success.

    Science.gov (United States)

    Lang, Stacey; Powers, Kristi

    2013-12-01

    Healthcare finance leaders can work with orthopedic surgeons to support better outcomes, clinically and financially, by: Establishing innovative partnerships among hospital leaders, orthopedic surgeons, and implant vendors. Developing and enforcing expectations around contracting and vendor behavior. Establishing a forum for open communication. Building a bundled payment structure. Finding ways to differentiate from the competition.

  12. A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Han Yong; Zhou Jianhong; Zhang Lan; Xu Kewei, E-mail: yonghan@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China)

    2011-07-08

    We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca{sup 2+}, Sr{sup 2+} and PO{sub 4}{sup 3-} ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca{sub 0.5}Sr{sub 0.5}TiO{sub 3} pre-formed on the TiO{sub 2} and grow in length to nanofibers at the expense of Ca{sup 2+}, Sr{sup 2+} and PO{sub 4}{sup 3-} ions that migrate from the TiO{sub 2}. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

  13. A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold.

    Science.gov (United States)

    Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

    2011-07-08

    We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2+, Sr2+ and PO4(3-) ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2+, Sr2+ and PO4(3-) ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

  14. Development and characterization of multi-element doped hydroxyapatite bioceramic coatings on metallic implants for orthopedic applications

    International Nuclear Information System (INIS)

    Furko, M.; Havasi, V.; Kónya, Z.; Grünewald, D.; Detsch, R.; Boccaccini, A.R.; Balázsi, C.

    2018-01-01

    Multi-element modified bioactive hydroxyapatite bioceramic (mHAp) coatings were successfully developed onto surgical grade titanium alloy material (Ti6Al4V). The coatings were prepared by pulse current deposition from electrolyte containing adequate amounts of calcium nitrate and ammonium dihydrogen phosphate at 70C. The pure HAp layer was doped and co-deposited with Ag, Zn, Mg, Sr ions. The biocompatible properties of layers were investigated by seeding osteoblast-like MG-63 cells onto the samples’ surface. The biocompatible measurements revealed enhanced bioactivity of modified HAp compared to uncoated implant materials and pure bioceramic coating. The morphology and structure of coatings and cells were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) as well as FT-IR and XRD measurements. The biodegradable properties of samples were investigated by electrochemical potentiodynamic measurements. [es

  15. Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant?abutment connection

    OpenAIRE

    Semper-Hogg, Wiebke; Kraft, Silvan; Stiller, Sebastian; Mehrhof, Juergen; Nelson, Katja

    2012-01-01

    Objectives Position stability of the abutment should be investigated in four implant systems with a conical implant?abutment connection. Materials and methods Previously developed formulas and an established experimental setup were used to determine the position stability of the abutment in the four implant systems with a conical implant?abutment connection and different positional index designs: The theoretical rotational freedom was calculated by using the dimensions of one randomly selecte...

  16. Technologien rund um orthopädische Implantate: Vortrag gehalten bei Prosthesia Meet & Match; Innovate in Orthopedic Implants; Innovez dans les Implants Orthopediques; Orthopaidsche Implantate: entwickeln wir sie weiter; Thursday, March 29th 2012, Illkirch

    OpenAIRE

    Schneider, Urs

    2012-01-01

    Die Innovationstreiber alternde Gesellschaft, dynamsiche Veränderungen in der Gesundheitspolitik der Zielländer, spezielle Marktveränderungen im Gesundheitswesen, Technologietrends und Fortentwicklung orthopädischer Therapieverfahren werden diskutiert. Im Forschungsfeld neuer Materialien hat die Welt der orthopädischen Implantate mittlerweile alle anderen Medizintechnikfelder hinter sich gelassen. Neue technische Lösungen des Fraunhofer IPA und der Fraunhofer Gesellschaft werden vorgestellt....

  17. Medical Issues: Orthopedics

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > orthopedics Orthopedics In SMA, muscle weakness can cause ...

  18. Implant stability and marginal bone level of microgrooved zirconia dental implants: A 3-month experimental study on dogs

    Directory of Open Access Journals (Sweden)

    Delgado-Ruíz Rafael Arcesio

    2014-01-01

    Full Text Available Background/Aim. The modification of implant surfaces could affect mechanical implant stability as well as dynamics and quality of peri-implant bone healing. The aim of this 3-month experimental study in dogs was to investigate implant stability, marginal bone levels and bone tissue response to zirconia dental implants with two laser-micro-grooved intraosseous surfaces in comparison with nongrooved sandblasted zirconia and sandblasted, high-temperature etched titanium implants. Methods. Implant surface characterization was performed using optical interferometric profilometry and energy dispersive X-ray spectroscopy. A total of 96 implants (4 mm in diameter and 10 mm in length were inserted randomly in both sides of the lower jaw of 12 Fox Hound dogs divided into groups of 24 each: the control (titanium, the group A (sandblasted zirconia, the group B (sandblasted zirconia plus microgrooved neck and the group C (sandblasted zirconia plus all microgrooved. All the implants were immediately loaded. Insertion torque, periotest values, radiographic crestal bone level and removal torque were recorded during the 3-month follow-up. Qualitative scanning electon micro-scope (SEM analysis of the bone-implant interfaces of each group was performed. Results. Insertion torque values were higher in the group C and control implants (p the control > the group B > the group A (p the control > the group B > the group A (p < 0.05. SEM showed that implant surfaces of the groups B and C had an extra bone growth inside the microgrooves that corresponded to the shape and direction of the microgrooves. Conclusion. The addition of micro-grooves to the entire intraosseous surface of zirconia dental implants enhances primary and secondary implant stability, promotes bone tissue ingrowth and preserves crestal bone levels.

  19. Spontaneous progression of ligature induced peri-implantitis at implants with different surface roughness: an experimental study in dogs

    DEFF Research Database (Denmark)

    Berglundh, T; Gotfredsen, K; Zitzmann, N U

    2007-01-01

    : The aim of the current experiment was to study the progression of peri-implantitis around implants with different surface roughness. MATERIAL AND METHODS: In five beagle dogs, three implants with either a sandblasted acid-etched surface (SLA) or a polished surface (P) were installed bilaterally......BACKGROUND: Peri-implantitis is associated with the presence of submarginal plaque, soft-tissue inflammation and advanced breakdown of the supporting bone. The progression of peri-implantitis following varying periods of continuing plaque accumulation has been studied in animal models. OBJECTIVE...... in the edentulous premolar regions. After 3 months on a plaque control regimen, experimental peri-implantitis was induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. After this 4-month period, ligatures were removed...

  20. Superficial or deep implantation of motor nerve after denervation: an experimental study--superficial or deep implantation of motor nerve.

    Science.gov (United States)

    Askar, Ibrahím; Sabuncuoglu, Bízden Tavíl

    2002-01-01

    Neurorraphy, conventional nerve grafting technique, and artificial nerve conduits are not enough for repair in severe injuries of peripheral nerves, especially when there is separation of motor nerve from muscle tissue. In these nerve injuries, reinnervation is indicated for neurotization. The distal end of a peripheral nerve is divided into fascicles and implanted into the aneural zone of target muscle tissue. It is not known how deeply fascicles should be implanted into muscle tissue. A comparative study of superficial and deep implantation of separated motor nerve into muscle tissue is presented in the gastrocnemius muscle of rabbits. In this experimental study, 30 white New Zealand rabbits were used and divided into 3 groups of 10 rabbits each. In the first group (controls, group I), only surgical exposure of the gastrocnemius muscle and motor nerve (tibial nerve) was done without any injury to nerves. In the superficial implantation group (group II), tibial nerves were separated and divided into their own fascicles. These fascicles were implanted superficially into the lateral head of gastrocnemius muscle-aneural zone. In the deep implantation group (group III), the tibial nerves were separated and divided into their own fascicles. These fascicles were implanted around the center of the muscle mass, into the lateral head of the gastrocnemius muscle-aneural zone. Six months later, histopathological changes and functional recovery of the gastrocnemius muscle were investigated. Both experimental groups had less muscular weight than in the control group. It was found that functional recovery was achieved in both experimental groups, and was better in the superficial implantation group than the deep implantation group. EMG recordings revealed that polyphasic and late potentials were frequently seen in both experimental groups. Degeneration and regeneration of myofibrils were observed in both experimental groups. New motor end-plates were formed in a scattered

  1. Experimental investigation of commercial small diameter dental implants in porcine mandibular segments.

    Science.gov (United States)

    Hasan, Istabrak; Heinemann, Friedhelm; Schwegmann, Monika; Keilig, Ludger; Stark, Helmut; Bourauel, Christoph

    2017-02-01

    Small diameter (mini) dental implants have become more popular in recent years as alternatives to classical implant treatment in clinical cases with critical bony situations. However, an in-depth scientific analysis of the mechanical and biomechanical effects of small diameter implants has not yet been published. The aim of the present study was to investigate experimentally different commercial mini implants by measuring their displacements under immediate loading. Twelve commercially available mini implants were measured. Implants were inserted into porcine mandibular segments and loaded by means of a predefined displacement of 0.5 mm of the loading system. The implants were loaded at an angle of 30° to the implant long axis using the self-developed biomechanical hexapod measurement system. Implant displacements were registered. The experimental results were compared to the numerical ones from a previous study. Measured implant displacements were within the range of 39-194 μm. A large variation in the displacements was obtained among the different implant systems due to the different designs and thread profiles. Comparing experimental and numerical results, the displacements that were obtained numerically were within the range of 79-347 μm. The different commercial mini implants showed acceptable primary stability and could be loaded immediately after their insertion.

  2. Evaluation of bone loss in antibacterial coated dental implants: An experimental study in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Godoy-Gallardo, Maria [Department of Micro- and Nanotechnology, Technical University of Denmark, Kongens Lyngby (Denmark); Manzanares-Céspedes, Maria Cristina [Unidad de Anatomía y Embriología Humana, Faculty of Dentistry, University of Barcelona, Barcelona (Spain); Sevilla, Pablo [Department of Mechanics, Escola Universitària Salesiana de Sarrià (EUSS), Barcelona (Spain); Nart, José [Department of Periodontology, School of Dentistry, Universitat Internacional de Catalunya, Sant Cugat (Spain); Manzanares, Norberto [Unidad de Anatomía y Embriología Humana, Faculty of Dentistry, University of Barcelona, Barcelona (Spain); Manero, José M. [Biomaterials, Biomechanics and Tissue Engineering Group, Dept. Materials Science and Metallurgical Engineering, Technical University of Catalonia (UPC-BarcelonaTECH), Barcelona (Spain); Centre for Research in NanoEngineering (CRNE), UPC-BarcelonaTECH, Barcelona (Spain); Gil, Francisco Javier [Universitat Internacional de Catalunya, Sant Cugat (Spain); Boyd, Steven K. [McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, Alberta (Canada); Rodríguez, Daniel, E-mail: daniel.rodriguez.rius@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Dept. Materials Science and Metallurgical Engineering, Technical University of Catalonia (UPC-BarcelonaTECH), Barcelona (Spain); Centre for Research in NanoEngineering (CRNE), UPC-BarcelonaTECH, Barcelona (Spain)

    2016-12-01

    The aim of this study was to evaluate the in vivo effect of antibacterial modified dental implants in the first stages of peri-implantitis. Thirty dental implants were inserted in the mandibular premolar sites of 5 beagle dogs. Sites were randomly assigned to Ti (untreated implants, 10 units), Ti-Ag (silver electrodeposition treatment, 10 units), and Ti-TSP (silanization treatment, 10 units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated by ligature placement. Ligatures were removed 2 months later, and plaque formation was allowed for 2 additional months. Clinical and radiographic analyses were performed during the study. Implant-tissue samples were prepared for micro computed tomography, backscattered scanning electron microscopy, histomorphometric and histological analyses and ion release measurements. X-ray, SEM and histology images showed that vertical bone resorption in treated implants was lower than in the control group (P < 0.05). This effect is likely due to the capacity of the treatments to reduce bacteria colonization on the implant surface. Histological analysis suggested an increase of peri-implant bone formation on silanized implants. However, the short post-ligature period was not enough to detect differences in clinical parameters among implant groups. Within the limits of this study, antibacterial surface treatments have a positive effect against bone resorption induced by peri-implantitis. - Highlights: • Dental implants were modified with two antibacterial treatments, silver and TESPSA silanization. • Performance of the modified dental implants was studied in vivo. • Treated implants showed less peri-implant bone resorption. • Decrease in bone resorption was attributed to the antibacterial surface treatments. • Silane treatment enhanced bone regeneration around dental implants.

  3. Evaluation of bone loss in antibacterial coated dental implants: An experimental study in dogs

    International Nuclear Information System (INIS)

    Godoy-Gallardo, Maria; Manzanares-Céspedes, Maria Cristina; Sevilla, Pablo; Nart, José; Manzanares, Norberto; Manero, José M.; Gil, Francisco Javier; Boyd, Steven K.; Rodríguez, Daniel

    2016-01-01

    The aim of this study was to evaluate the in vivo effect of antibacterial modified dental implants in the first stages of peri-implantitis. Thirty dental implants were inserted in the mandibular premolar sites of 5 beagle dogs. Sites were randomly assigned to Ti (untreated implants, 10 units), Ti-Ag (silver electrodeposition treatment, 10 units), and Ti-TSP (silanization treatment, 10 units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated by ligature placement. Ligatures were removed 2 months later, and plaque formation was allowed for 2 additional months. Clinical and radiographic analyses were performed during the study. Implant-tissue samples were prepared for micro computed tomography, backscattered scanning electron microscopy, histomorphometric and histological analyses and ion release measurements. X-ray, SEM and histology images showed that vertical bone resorption in treated implants was lower than in the control group (P < 0.05). This effect is likely due to the capacity of the treatments to reduce bacteria colonization on the implant surface. Histological analysis suggested an increase of peri-implant bone formation on silanized implants. However, the short post-ligature period was not enough to detect differences in clinical parameters among implant groups. Within the limits of this study, antibacterial surface treatments have a positive effect against bone resorption induced by peri-implantitis. - Highlights: • Dental implants were modified with two antibacterial treatments, silver and TESPSA silanization. • Performance of the modified dental implants was studied in vivo. • Treated implants showed less peri-implant bone resorption. • Decrease in bone resorption was attributed to the antibacterial surface treatments. • Silane treatment enhanced bone regeneration around dental implants.

  4. Experimental study on bone tissue reaction around HA implants radiated after implantation

    International Nuclear Information System (INIS)

    Kudo, Masato; Matsui, Yoshiro; Tamura, Sayaka; Chen, Xuan; Uchida, Haruo; Mori, Kimie; Ohno, Kohsuke; Michi, Ken-ichi

    1998-01-01

    This study was conducted to investigate histologically and histomorphometrically the tissue reaction around hydroxylapatite (HA) implants that underwent irradiation in 3 different periods in the course of bone healing after implantation. The cylindrical high-density HA implants were implanted in 48 Japanese white rabbit mandibles. A single 15 Gy dose was applied to the mandible 5, 14, or 28 days after implantation. The rabbits were sacrificed 7, 14, 28, and 90 days after irradiation. Nonirradiated rabbits were used as controls. CMR, labeling with tetracycline and calcein, and non-decalcified specimens stained with toluidine blue were used for histological analyses and histomorphometric measurements. The results were as follows: In the rabbits irradiated 5 days after implantation, the HA-bone contact was observed later than that in the controls and the bone-implant contact surface ratio was lower than that in the controls at examination because necrosis of the newly-formed bone occurred just after irradiation. HA-bone contact of the rabbits irradiated 14 and 28 days after implantation was similar to that of the controls. And, bone remodeling was suppressed in rabbits of each group sacrificed at 90 days after irradiation. The results suggested that a short interval between implantation and irradiation causes direct contact between HA implant and bone and a long lapse of time before irradiation hardly affects the bone-implant contact, but delays bone remodeling. Therefore, it is necessary to prevent overloading the HA implants irradiated after implantation and pay utmost attention to conditions around the bone-implant contact. (author)

  5. Effect of insertion torque on titanium implant osseointegration: an animal experimental study.

    Science.gov (United States)

    Duyck, Joke; Roesems, Rutger; Cardoso, Marcio V; Ogawa, Toru; De Villa Camargos, Germana; Vandamme, Katleen

    2015-02-01

    To evaluate the effect of implant insertion torque on the peri-implant bone healing and implant osseointegration. Bilaterally in the tibia of five adult New Zealand white rabbits, 20 implants were installed, subdivided into four groups, corresponding to two insertion torque conditions (low, 50 Ncm) and 2 experimental periods (2 weeks vs. 4 weeks of healing). The implant insertion torque was determined by the surgical drill diameter relative to the implant diameter. Implant osseointegration was evaluated by quantitative histology (bone-to-implant contact with host bone [BIC-host], with neoformed bone [BIC-de novo], with both bone types [BIC-total], and peri-implant bone [BA/TA]). Every response was modelled over time using GEE (general estimation equation) with an unstructured variance-covariance matrix to correct for dependency between the measurements from one animal. The statistical significance level of α = 0.05 was applied. Significantly, more BIC-host and BIC-total were recorded for H implants compared with L implants after 2 week of healing (P = 0.010 and P = 0.0001, respectively). However, this result was no longer found for the extended healing period. Furthermore, BIC-total significantly increased over time for L implants (P torque led to an increased BA/TA after 4 week of healing (P torque implants installed in the rabbit tibial bone osseointegrate with considerable de novo bone formation. This bone neoformation enables L implants to catch up, already during the early osseointegration stage, the initial inferior amount BIC contact compared with that of H implants. A negative impact of the created strain environment accompanying H insertion torque implant installation on the biological process of osseointegration could not be observed, at least not at tissue level. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Expansão rápida da maxila ancorada em implantes: uma nova proposta para expansão ortopédica na dentadura permanente Rapid maxillary expansion anchored by implants: a new proposal to orthopedic expansion in the permanent dentition

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2007-06-01

    Full Text Available OBJETIVO: este trabalho apresenta um método para expansão ortopédica da maxila, na dentadura permanente, utilizando implantes como ancoragem. METODOLOGIA: detalharam-se os procedimentos cirúrgicos e laboratoriais da confecção de um expansor com ancoragem dento-óssea em crânio seco humano. Dois implantes de titânio foram colocados na região anterior do palato, e o parafuso Hyrax adaptado de modo que a expansão ancorou-se nos implantes e nos primeiros molares permanentes. RESULTADOS: o experimento laboratorial em crânio seco mostrou que o procedimento apresenta-se anatômica e operacionalmente viável. Os implantes suportaram a força gerada pela ativação do parafuso expansor, redundando na separação transversal das hemimaxilas. CONCLUSÕES: vislumbra-se que a expansão rápida da maxila ancorada em implantes (ERMAI poderá potencializar a eficiência da expansão ortopédica, assim como reduzir o custo periodontal dos procedimentos convencionais de expansão. Futuros estudos clínicos são necessários para testar essas hipóteses.AIM: This study presents a method for maxillary orthopedic expansion, in the permanent dentition, using implants as anchorage. METHODS: Surgical and laboratorial procedures for the construction of a tooth-bone-borne expansor was detailed in a human dry skull. Two titanium implants were placed in the anterior region of the palate and a Hyrax screw was adapted in a way that the expansion was anchored both on the palatal implants and on permanent first molars. RESULTS: The laboratorial experiment in dry skull showed that the procedure is operationally and anatomically possible. The implants supported the force generated by the expansion screw activation and the maxilla halves were transversally split. CONCLUSIONS: Rapid maxillary expansion anchored on implants can increase the efficiency of orthopedic expansion and decrease the periodontal sequela caused by conventional RME. Further clinical studies are

  7. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    Directory of Open Access Journals (Sweden)

    Stamatović Novak

    2013-01-01

    Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

  8. Experimental studies of N~+ implantation into CVD diamond thin films

    Institute of Scientific and Technical Information of China (English)

    辛火平; 林成鲁; 王建新; 邹世昌; 石晓红; 林梓鑫; 周祖尧; 刘祖刚

    1997-01-01

    The effects of N+ implantation under various conditions on CVD diamond films were analyzed with Raman spectroscopy, four-point probe method, X-ray diffraction (XRD), Rutherford backseattering spectroscopy (RBS), ultraviolet photoluminescence spectroscopy (UV-PL), Fourier transformation infrared absorption spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the N+ implantation doping without any graphitization has been successfully realized when 100 keV N+ ions at a dosage of 2 × 1016 cm-2 were implanted into diamond films at 550℃ . UV-PL spectra indicate that the implanted N+ ions formed an electrically inactive deep-level impurity in diamond films. So the sheet resistance of the sample after N+ implantation changed little. Carbon nitride containing C≡N covalent bond has been successfully synthesized by 100 keV, 1.2×1018 N/cm2 N+ implantation into diamond films. Most of the implanted N+ ions formed C≡N covalent bonds with C atoms. The others were free state nitroge

  9. Experimental research of covered stent implanted in canine hepatic artery

    International Nuclear Information System (INIS)

    Zhou Bing; Liu Linxiang; Li Minghua; Wang Yongli; Cheng Yongde

    2007-01-01

    Objective: To evaluate the feasibility of success rate of implantation, post-procedure stenosis rate, apposition ability and endothelialization level, etc. for implantation with balloon-expandable covered stent in canine hepatic artery. Methods: 8 adult canines were implanted with balloon-expendable stents covered by expandable poly Teflon ester membrane (e-PTFEM). Follow-up DSA was performed immediately, 2, 4 and 12 wk after the procedure. The canines were sacrificed for histopathologic examination and statistical analysis with correlation of implantation manenvor and angiographic manifestations. Results: 8 cases were all implanted with the covered stents in proper hepatic artery/right hepatic artery successfully; showing good apposition ability and non-opacification of the separated branches. 2 cases showed intraluminal obvious stenosis( > 50%)of the stent at 2 weeks follow-up, so did 3 cases at 12 weeks follow-up, and the total stenosis rate was 37.5% and 5 cases manifested full endothelialization (3 different locations of the sample all manifested full endothelialization), 3 cased manifested partial endothelialization (at least 1 location of the sample didn't show full endothelialization), and the two terminal parts were easier to get endothelialization than the central part. Before and after the stent implantation, hepatic function of all cases didn't demonstrate any obvious changes. Conclusions: Balloon-expandable covered stent can be implanted in canine hepatic artery. successfully, with good apposition ability, full endothelialization, and no influence on hepatic function. (authors)

  10. In vivo study of nanostructured diopside (CaMgSi{sub 2}O{sub 6}) coating on magnesium alloy as biodegradable orthopedic implants

    Energy Technology Data Exchange (ETDEWEB)

    Razavi, Mehdi, E-mail: mrzavi2659@gmail.com [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Fathi, Mohammadhossein [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Dental Materials Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Savabi, Omid [Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); Razavi, Seyed Mohammad [School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); Heidari, Fariba; Manshaei, Maziar [Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); Vashaee, Daryoosh [School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Tayebi, Lobat, E-mail: lobat.tayebi@okstate.edu [School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States)

    2014-09-15

    Highlights: • In vitro biocompatibility of biodegradable Mg alloy was improved by diopside coating. • In vivo biocompatibility of biodegradable Mg alloy was improved by diopside coating. • Degradation behavior of biodegradable Mg alloy was improved by diopside coating. - Abstract: In order to improve the corrosion resistance and bioactivity of a biodegradable magnesium alloy, we have recently prepared a nanostructured diopside (CaMgSi{sub 2}O{sub 6}) coating on AZ91 magnesium alloy through a combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) method (reported elsewhere). In this work, we performed a detailed biocompatibility analysis of the implants made by this material and compared their performance with those of the uncoated and micro arc oxidized magnesium implants. The biocompatibility evaluation of samples was performed by culturing L-929 cells and in vivo animal study, including implantation of samples in greater trochanter of rabbits, radiography and histological examinations. The results from both the in vitro and in vivo studies indicated that the diopside/MAO coated magnesium implant significantly enhanced cell viability, biodegradation resistance and new bone formation compared with both the uncoated and the micro-arc oxidized magnesium implants. Our data provides an example of how the proper surface treatment of magnesium implants can overcome their drawbacks in terms of high degradation rate and gas bubble formation under physiological conditions.

  11. In vivo study of nanostructured diopside (CaMgSi2O6) coating on magnesium alloy as biodegradable orthopedic implants

    International Nuclear Information System (INIS)

    Razavi, Mehdi; Fathi, Mohammadhossein; Savabi, Omid; Razavi, Seyed Mohammad; Heidari, Fariba; Manshaei, Maziar; Vashaee, Daryoosh; Tayebi, Lobat

    2014-01-01

    Highlights: • In vitro biocompatibility of biodegradable Mg alloy was improved by diopside coating. • In vivo biocompatibility of biodegradable Mg alloy was improved by diopside coating. • Degradation behavior of biodegradable Mg alloy was improved by diopside coating. - Abstract: In order to improve the corrosion resistance and bioactivity of a biodegradable magnesium alloy, we have recently prepared a nanostructured diopside (CaMgSi 2 O 6 ) coating on AZ91 magnesium alloy through a combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) method (reported elsewhere). In this work, we performed a detailed biocompatibility analysis of the implants made by this material and compared their performance with those of the uncoated and micro arc oxidized magnesium implants. The biocompatibility evaluation of samples was performed by culturing L-929 cells and in vivo animal study, including implantation of samples in greater trochanter of rabbits, radiography and histological examinations. The results from both the in vitro and in vivo studies indicated that the diopside/MAO coated magnesium implant significantly enhanced cell viability, biodegradation resistance and new bone formation compared with both the uncoated and the micro-arc oxidized magnesium implants. Our data provides an example of how the proper surface treatment of magnesium implants can overcome their drawbacks in terms of high degradation rate and gas bubble formation under physiological conditions

  12. Acceleration of Medpor implant fibrovascularization with local vascular endothelial growth-factor injections: An experimental study

    Directory of Open Access Journals (Sweden)

    Mert Demirel

    2015-12-01

    Full Text Available Objective: Medpor is a biocompatible, high-density porous polyethylene implant that is used for multiple indications in plastic surgery. The most frequent complications associated with the Medpor implant are infection and implant exposure. The primary cause of these complications is poor fibrovascularization of the Medpor implant and poor nourishment of the overlying skin. The present experimental study aimed to determine whether vascular endothelial growth factor (VEGF could accelerate and increase Medpor implant fibrovascularization in vivo, and thereby improve local nourishment and prevent complications. Materials and Methods: The Medpor implant was inserted under the dorsal skin area in 40 Sprague-Dawley rats. 20 rats receiving local VEGF injections comprised the study group. The control group received saline injections. Fibrovascularization of the Medpor implants was compared. Results: In the rats injected with VEGF, the Medpor implant fibrovascularized faster, and there were more newly formed blood vessels, as compared with those in the control group. Conclusion: These findings have led to our use of VEGF-like agents that the accelerate angiogenesis in the Medpor implant as a means to reduce the incidence of such complications as infection and implant exposure. [Arch Clin Exp Surg 2015; 4(4.000: 196-201

  13. Platelet-rich plasma in orthopedic therapy: a comparative systematic review of clinical and experimental data in equine and human musculoskeletal lesions.

    Science.gov (United States)

    Brossi, Patrícia M; Moreira, Juliana J; Machado, Thaís S L; Baccarin, Raquel Y A

    2015-04-22

    This systematic review aimed to present and critically appraise the available information on the efficacy of platelet rich plasma (PRP) in equine and human orthopedic therapeutics and to verify the influence of study design and methodology on the assumption of PRP's efficacy. We searched Medline, PubMed, Embase, Bireme and Google Scholar without restrictions until July 2013. Randomized trials, human cohort clinical studies or case series with a control group on the use of PRP in tendons, ligaments or articular lesions were included. Equine clinical studies on the same topics were included independently of their design. Experimental studies relevant to the clarification of PRP's effects and mechanisms of action in tissues of interest, conducted in any animal species, were selected. This review included 123 studies. PRP's beneficial effects were observed in 46.7% of the clinical studies, while the absence of positive effects was observed in 43.3%. Among experimental studies, 73% yielded positive results, and 7.9% yielded negative results. The most frequent flaws in the clinical trials' designs were the lack of a true placebo group, poor product characterization, insufficient blinding, small sampling, short follow-up periods, and adoption of poor outcome measures. The methods employed for PRP preparation and administration and the selected outcome measures varied greatly. Poor study design was a common feature of equine clinical trials. From studies in which PRP had beneficial effects, 67.8% had an overall high risk of bias. From the studies in which PRP failed to exhibit beneficial effects, 67.8% had an overall low risk of bias. Most experimental studies revealed positive effects of PRP. Although the majority of equine clinical studies yielded positive results, the human clinical trials' results failed to corroborate these findings. In both species, beneficial results were more frequently observed in studies with a high risk of bias. The use of PRP in musculoskeletal

  14. Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

    International Nuclear Information System (INIS)

    Pilmane, M; Salms, G; Salma, I; Skagers, A; Locs, J; Loca, D; Berzina-Cimdina, L

    2011-01-01

    Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNFα), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both - experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.

  15. Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

    Energy Technology Data Exchange (ETDEWEB)

    Pilmane, M [Riga Stradins University, Institute of Anatomy and Anthropology, Dzirciema 16, LV-1007, Riga (Latvia); Salms, G; Salma, I; Skagers, A [Riga Stradins University, Department of Oral and Maxillofacial Surgery, Dzirciema 20. LV-1007, Riga (Latvia); Locs, J; Loca, D; Berzina-Cimdina, L, E-mail: pilmane@latnet.lv [Riga Technical University, Riga Biomaterials innovation and development centre, Pulka 3/3, LV-1007, Riga (Latvia)

    2011-06-23

    Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNF{alpha}), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both - experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.

  16. Trends in Medicare Reimbursement for Orthopedic Procedures: 2000 to 2016.

    Science.gov (United States)

    Eltorai, Adam E M; Durand, Wesley M; Haglin, Jack M; Rubin, Lee E; Weiss, Arnold-Peter C; Daniels, Alan H

    2018-03-01

    Understanding trends in reimbursement is critical to the financial sustainability of orthopedic practices. Little research has examined physician fee trends over time for orthopedic procedures. This study evaluated trends in Medicare reimbursements for orthopedic surgical procedures. The Medicare Physician Fee Schedule was examined for Current Procedural Terminology code values for the most common orthopedic and nonorthopedic procedures between 2000 and 2016. Prices were adjusted for inflation to 2016-dollar values. To assess mean growth rate for each procedure and subspecialty, compound annual growth rates were calculated. Year-to-year dollar amount changes were calculated for each procedure and subspecialty. Reimbursement trends for individual procedures and across subspecialties were compared. Between 2000 and 2016, annual reimbursements decreased for all orthopedic procedures examined except removal of orthopedic implant. The orthopedic procedures with the greatest mean annual decreases in reimbursement were shoulder arthroscopy/decompression, total knee replacement, and total hip replacement. The orthopedic procedures with the least annual reimbursement decreases were carpal tunnel release and repair of ankle fracture. Rate of Medicare procedure reimbursement change varied between subspecialties. Trauma had the smallest decrease in annual change compared with spine, sports, and hand. Annual reimbursement decreased at a significantly greater rate for adult reconstruction procedures than for any of the other subspecialties. These findings indicate that reimbursement for procedures has steadily decreased, with the most rapid decrease seen in adult reconstruction. [Orthopedics. 2018; 41(2):95-102.]. Copyright 2018, SLACK Incorporated.

  17. Robotics in Orthopedics: A Brave New World.

    Science.gov (United States)

    Parsley, Brian S

    2018-02-16

    Future health-care projection projects a significant growth in population by 2020. Health care has seen an exponential growth in technology to address the growing population with the decreasing number of physicians and health-care workers. Robotics in health care has been introduced to address this growing need. Early adoption of robotics was limited because of the limited application of the technology, the cumbersome nature of the equipment, and technical complications. A continued improvement in efficacy, adaptability, and cost reduction has stimulated increased interest in robotic-assisted surgery. The evolution in orthopedic surgery has allowed for advanced surgical planning, precision robotic machining of bone, improved implant-bone contact, optimization of implant placement, and optimization of the mechanical alignment. The potential benefits of robotic surgery include improved surgical work flow, improvements in efficacy and reduction in surgical time. Robotic-assisted surgery will continue to evolve in the orthopedic field. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Experimental rat lung tumor model with intrabronchial tumor cell implantation.

    Science.gov (United States)

    Gomes Neto, Antero; Simão, Antônio Felipe Leite; Miranda, Samuel de Paula; Mourão, Lívia Talita Cajaseiras; Bezerra, Nilfácio Prado; Almeida, Paulo Roberto Carvalho de; Ribeiro, Ronaldo de Albuquerque

    2008-01-01

    The objective of this study was to develop a rat lung tumor model for anticancer drug testing. Sixty-two female Wistar rats weighing 208 +/- 20 g were anesthetized intraperitoneally with 2.5% tribromoethanol (1 ml/100 g live weight), tracheotomized and intubated with an ultrafine catheter for inoculation with Walker's tumor cells. In the first step of the experiment, a technique was established for intrabronchial implantation of 10(5) to 5 x 10(5) tumor cells, and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from high-resolution computed tomography (HRCT) with findings from necropsia and determining time of survival. The tumor take rate was 94.7% for implants with 4 x 10(5) tumor cells, HRCT and necropsia findings matched closely (r=0.953; p<0.0001), the median time of survival was 11 days, and surgical mortality was 4.8%. The present rat lung tumor model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. HRCT was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

  19. Experimental identification of nitrogen-vacancy complexes in nitrogen implanted silicon

    Science.gov (United States)

    Adam, Lahir Shaik; Law, Mark E.; Szpala, Stanislaw; Simpson, P. J.; Lawther, Derek; Dokumaci, Omer; Hegde, Suri

    2001-07-01

    Nitrogen implantation is commonly used in multigate oxide thickness processing for mixed signal complementary metal-oxide-semiconductor and System on a Chip technologies. Current experiments and diffusion models indicate that upon annealing, implanted nitrogen diffuses towards the surface. The mechanism proposed for nitrogen diffusion is the formation of nitrogen-vacancy complexes in silicon, as indicated by ab initio studies by J. S. Nelson, P. A. Schultz, and A. F. Wright [Appl. Phys. Lett. 73, 247 (1998)]. However, to date, there does not exist any experimental evidence of nitrogen-vacancy formation in silicon. This letter provides experimental evidence through positron annihilation spectroscopy that nitrogen-vacancy complexes indeed form in nitrogen implanted silicon, and compares the experimental results to the ab initio studies, providing qualitative support for the same.

  20. The effects of hydroxyapatite coating and bone allograft on fixation of loaded experimental primary and revision implants

    DEFF Research Database (Denmark)

    Søballe, Kjeld; Mouzin, Olivier R G; Kidder, Louis A

    2003-01-01

    We used our established experimental model of revision joint replacement to examine the roles of hydroxyapatite coating and bone graft in improving the fixation of revision implants. The revision protocol uses the Søballe micromotion device in a preliminary 8-week period of implant instability...... a titanium alloy (Ti) or a hydroxyapatite (HA) 6.0 mm plasma-sprayed implant, in the presence or absence of allograft packed into the initial 0.75 mm peri-implant gap. The contralateral limb is subjected to primary surgery with the same implant configuration, and serves as control. 8 implants were included...

  1. Processing considerations with plasma-based ion implantation of polymers: theoretical aspects, limitations, and experimental results

    International Nuclear Information System (INIS)

    Lacoste, A.; Pelletier, J.

    2003-01-01

    Processing of polymers using plasma-based ion implantation techniques (PBII) has general implications in terms of plasma specifications and pulse characteristics. In particular, the different aspects of the processing of polymer layers are discussed as functions of plasma density, pulse duration, and layer characteristics (thickness and permittivity). Clearly, severe limitations (true implantation energy, arcing) may appear for high-density plasmas as well as for long pulse durations, when processing polymer layers with thickness in the mm range. A review of the experimental results of ion implantation in polymeric materials via PBII processing is presented. The experimental results demonstrate the possibility of processing polymer layers with the PBII technique, but with severe limitations resulting from the process itself

  2. The Mechanical Properties and In Vitro Biocompatibility of PM-Fabricated Ti-28Nb-35.4Zr Alloy for Orthopedic Implant Applications

    Science.gov (United States)

    Xu, Wei; Li, Ming; Wen, Cuie; Lv, Shaomin; Liu, Chengcheng; Lu, Xin

    2018-01-01

    A biocompatible Ti-28Nb-35.4Zr alloy used as bone implant was fabricated through the powder metallurgy process. The effects of mechanical milling and sintering temperatures on the microstructure and mechanical properties were investigated systematically, before in vitro biocompatibility of full dense Ti-28Nb-35.4Zr alloy was evaluated by cytotoxicity tests. The results show that the mechanical milling and sintering temperatures have significantly effects on the density and mechanical properties of the alloys. The relative density of the alloy fabricated by the atomized powders at 1500 °C is only 83 ± 1.8%, while the relative density of the alloy fabricated by the ball-milled powders can rapidly reach at 96.4 ± 1.3% at 1500 °C. When the temperature was increased to 1550 °C, the alloy fabricated by ball-milled powders achieve full density (relative density is 98.1 ± 1.2%). The PM-fabricated Ti-28Nb-35.4Zr alloy by ball-milled powders at 1550 °C can achieve a wide range of mechanical properties, with a compressive yield strength of 1058 ± 35.1 MPa, elastic modulus of 50.8 ± 3.9 GPa, and hardness of 65.8 ± 1.5 HRA. The in vitro cytotoxicity test suggests that the PM-fabricated Ti-28Nb-35.4Zr alloy by ball-milled powders at 1550 °C has no adverse effects on MC3T3-E1 cells with cytotoxicity ranking of 0 grade, which is nearly close to ELI Ti-6Al-4V or CP Ti. These properties and the net-shape manufacturability makes PM-fabricated Ti-28Nb-35.4Zr alloy a low-cost, highly-biocompatible, Ti-based biomedical alloy. PMID:29601517

  3. The Mechanical Properties and In Vitro Biocompatibility of PM-Fabricated Ti-28Nb-35.4Zr Alloy for Orthopedic Implant Applications.

    Science.gov (United States)

    Xu, Wei; Li, Ming; Wen, Cuie; Lv, Shaomin; Liu, Chengcheng; Lu, Xin; Qu, Xuanhui

    2018-03-30

    A biocompatible Ti-28Nb-35.4Zr alloy used as bone implant was fabricated through the powder metallurgy process. The effects of mechanical milling and sintering temperatures on the microstructure and mechanical properties were investigated systematically, before in vitro biocompatibility of full dense Ti-28Nb-35.4Zr alloy was evaluated by cytotoxicity tests. The results show that the mechanical milling and sintering temperatures have significantly effects on the density and mechanical properties of the alloys. The relative density of the alloy fabricated by the atomized powders at 1500 °C is only 83 ± 1.8%, while the relative density of the alloy fabricated by the ball-milled powders can rapidly reach at 96.4 ± 1.3% at 1500 °C. When the temperature was increased to 1550 °C, the alloy fabricated by ball-milled powders achieve full density (relative density is 98.1 ± 1.2%). The PM-fabricated Ti-28Nb-35.4Zr alloy by ball-milled powders at 1550 °C can achieve a wide range of mechanical properties, with a compressive yield strength of 1058 ± 35.1 MPa, elastic modulus of 50.8 ± 3.9 GPa, and hardness of 65.8 ± 1.5 HRA. The in vitro cytotoxicity test suggests that the PM-fabricated Ti-28Nb-35.4Zr alloy by ball-milled powders at 1550 °C has no adverse effects on MC3T3-E1 cells with cytotoxicity ranking of 0 grade, which is nearly close to ELI Ti-6Al-4V or CP Ti. These properties and the net-shape manufacturability makes PM-fabricated Ti-28Nb-35.4Zr alloy a low-cost, highly-biocompatible, Ti-based biomedical alloy.

  4. Tourniquets in orthopedic surgery

    Directory of Open Access Journals (Sweden)

    Jai Prakash Sharma

    2012-01-01

    Full Text Available Tourniquets are commonly used in limb surgeries, be it orthopedic or plastic surgeries. But the inflation pressures, the duration, and release guidelines are still not clear. According to a survey, majority of orthopedic surgeons inflate the tourniquet to fixed pressures for the upper and the lower limbs without considering the baseline blood pressure of the patient on whom the tourniquets are being applied. This review was designed to recall and review the safe use of tourniquets and the various techniques that can be employed to minimize the complications of tourniquet use. Google, science direct, and pubmed were searched for appropriate literature and relevant articles were identified.

  5. From acid etching treatments to tribocorrosive properties of dental implants: do some experimental results on surface treatments have an influence on the tribocorrosion behaviour of dental implants?

    International Nuclear Information System (INIS)

    Geringer, Jean; Demanget, Nicolas; Pellier, Julie

    2013-01-01

    Surface treatments of dental implants aim at promoting osseointegration, i.e. the anchorage of the metallic part. Titanium-, grade II–V, based material is used as a bulk material for dental implants. For promoting the anchorage of this metallic biomaterial in human jaw, some strategies have been applied for improving the surface state, i.e. roughness, topography and coatings. A case study, experimental study, is described with the method of acid etching on titanium grade 4, CpTi. The main goal is to find the right proportion in a mixture of two acids in order to obtain the best surface state. Finally, a pure theoretical prediction is quite impossible and some experimental investigations are necessary to improve the surface state. The described acid etching is compared with some other acid etching treatments and some coatings available on dental implants. Thus, the discussion is focused on the tribocorrosion behaviour of titanium-based materials. The purpose of the coating is that the lifetime under tribocorrosion is limited. Moreover, the surgery related to the implantation has a huge impact on the stability of dental implants. Thus, the performance of dental implants depends on factors related to surgery (implantation) that are difficult to predict from the biomaterial characteristics. From the tribocorrosion point of view, i.e. during the mastication step, the titanium material is submitted to some deleterious factors that cause the performance of dental implants to decrease. (paper)

  6. Synthesis and evaluation of MgF2 coatings by chemical conversion on magnesium alloys for producing biodegradable orthopedic implants of temporary use

    International Nuclear Information System (INIS)

    Casanova, P Y; Jaimes, K J; Parada, N J; Viejo, F; Hernández-Barrios, C A; Aparicio, M; Coy, A E

    2013-01-01

    The aim of the present work was the synthesis of biodegradable MgF 2 coatings by chemical conversion on the commercial Elektron 21 and AZ91D magnesium alloys, in aqueous HF solutions for different concentrations and temperatures. The chemical composition and morphology of the coatings were analyzed by scanning electron microscopy (SEM-EDX) and X-ray diffraction (XRD). On the other hand, their corrosion behavior was evaluated by gravimetric and electrochemical measurements in Hank's solution at 37°C for different immersion times. The experimental results revealed that chemical conversion in HF produced MgF 2 coatings which corrosion resistance was enhanced by increasing the HF concentration. Further, the microstructure and composition of the base alloy played a key role on the growth and degradation mechanisms of the MgF 2 coatings

  7. Effect of alpha-lipoic acid on endometrial implants in an experimental rat model.

    Science.gov (United States)

    Pınar, Neslihan; Soylu Karapınar, Oya; Özcan, Oğuzhan; Özgür, Tümay; Bayraktar, Suphi

    2017-10-01

    To investigate the antioxidant and anti-inflammatory effects of alpha-lipoic acid (ALA) in the treatment of endometriosis in an experimental rat model by evaluating biochemical and histopathologic parameters. Experimental endometriosis was induced by the peritoneal implantation of autologous endometrial tissue. The rats were randomly divided into two groups with eight rats each. Group I was intraperitoneally administered ALA 100 mg/kg/day for 14 days. Group II was intraperitoneally administered saline solution at the same dosage and over the same period. Endometrial implant volume was measured in both groups both pre- and post-treatment. Tumor necrosis factor alpha (TNF-α) was measured in peritoneal fluid. Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were assessed in serum. The implants were histopathologically evaluated. In the ALA group, the serum TOS and OSI levels, the endometrial implant volumes, the TNF-α levels in serum and peritoneal fluid, and the histopathologic scores were significantly lower compared to the control group (P < 0.05). Alpha-lipoic acid may have a therapeutic potential in the treatment of endometriosis due to its antioxidant and anti-inflammatory effects. © 2017 Société Française de Pharmacologie et de Thérapeutique.

  8. 3D-printed patient-specific applications in orthopedics

    Directory of Open Access Journals (Sweden)

    Wong KC

    2016-10-01

    Full Text Available Kwok Chuen Wong Department of Orthopedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong Abstract: With advances in both medical imaging and computer programming, two-dimensional axial images can be processed into other reformatted views (sagittal and coronal and three-dimensional (3D virtual models that represent a patients’ own anatomy. This processed digital information can be analyzed in detail by orthopedic surgeons to perform patient-specific orthopedic procedures. The use of 3D printing is rising and has become more prevalent in medical applications over the last decade as surgeons and researchers are increasingly utilizing the technology’s flexibility in manufacturing objects. 3D printing is a type of manufacturing process in which materials such as plastic or metal are deposited in layers to create a 3D object from a digital model. This additive manufacturing method has the advantage of fabricating objects with complex freeform geometry, which is impossible using traditional subtractive manufacturing methods. Specifically in surgical applications, the 3D printing techniques can not only generate models that give a better understanding of the complex anatomy and pathology of the patients and aid in education and surgical training, but can also produce patient-specific surgical guides or even custom implants that are tailor-made to the surgical requirements. As the clinical workflow of the 3D printing technology continues to evolve, orthopedic surgeons should embrace the latest knowledge of the technology and incorporate it into their clinical practice for patient-specific orthopedic applications. This paper is written to help orthopedic surgeons stay up-to-date on the emerging 3D technology, starting from the acquisition of clinical imaging to 3D printing for patient-specific applications in orthopedics. It 1 presents the necessary steps to prepare the medical images that are

  9. Experimental Analysis of Temperature Differences During Implant Site Preparation: Continuous Drilling Technique Versus Intermittent Drilling Technique.

    Science.gov (United States)

    Di Fiore, Adolfo; Sivolella, Stefano; Stocco, Elena; Favero, Vittorio; Stellini, Edoardo

    2018-02-01

    Implant site preparation through drilling procedures may cause bone thermonecrosis. The aim of this in vitro study was to evaluate, using a thermal probe, overheating at implant sites during osteotomies through 2 different drilling methods (continuous drilling technique versus intermittent drilling technique) using irrigation at different temperatures. Five implant sites 13 mm in length were performed on 16 blocks (fresh bovine ribs), for a total of 80 implant sites. The PT-100 thermal probe was positioned 5 mm from each site. Two physiological refrigerant solutions were used: one at 23.7°C and one at 6.0°C. Four experimental groups were considered: group A (continuous drilling with physiological solution at 23.7°C), group B (intermittent drilling with physiological solution at 23.7°C), group C (continuous drilling with physiological solution at 6.0°C), and group D (intermittent drilling with physiological solution at 6.0°C). The Wilcoxon rank-sum test (2-tailed) was used to compare groups. While there was no difference between group A and group B (W = 86; P = .45), statistically significant differences were observed between experimental groups A and C (W = 0; P =.0001), B and D (W = 45; P =.0005), and C and D (W = 41; P = .003). Implant site preparation did not affect the overheating of the bone. Statistically significant differences were found with the refrigerant solutions. Using both irrigating solutions, bone temperature did not exceed 47°C.

  10. Determination of the frictional coefficient of the implant-antler interface: experimental approach.

    Science.gov (United States)

    Hasan, Istabrak; Keilig, Ludger; Staat, Manfred; Wahl, Gerhard; Bourauel, Christoph

    2012-10-01

    The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5-0.7 and 0.3-0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens.

  11. Surgical simulation training in orthopedics: current insights.

    Science.gov (United States)

    Kalun, Portia; Wagner, Natalie; Yan, James; Nousiainen, Markku T; Sonnadara, Ranil R

    2018-01-01

    While the knowledge required of residents training in orthopedic surgery continues to increase, various factors, including reductions in work hours, have resulted in decreased clinical learning opportunities. Recent work suggests residents graduate from their training programs without sufficient exposure to key procedures. In response, simulation is increasingly being incorporated into training programs to supplement clinical learning. This paper reviews the literature to explore whether skills learned in simulation-based settings results in improved clinical performance in orthopedic surgery trainees. A scoping review of the literature was conducted to identify papers discussing simulation training in orthopedic surgery. We focused on exploring whether skills learned in simulation transferred effectively to a clinical setting. Experimental studies, systematic reviews, and narrative reviews were included. A total of 15 studies were included, with 11 review papers and four experimental studies. The review articles reported little evidence regarding the transfer of skills from simulation to the clinical setting, strong evidence that simulator models discriminate among different levels of experience, varied outcome measures among studies, and a need to define competent performance in both simulated and clinical settings. Furthermore, while three out of the four experimental studies demonstrated transfer between the simulated and clinical environments, methodological study design issues were identified. Our review identifies weak evidence as to whether skills learned in simulation transfer effectively to clinical practice for orthopedic surgery trainees. Given the increased reliance on simulation, there is an immediate need for comprehensive studies that focus on skill transfer, which will allow simulation to be incorporated effectively into orthopedic surgery training programs.

  12. Dexamethasone intravitreal implant downregulates PDGFR-α and upregulates caveolin-1 in experimental branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Cehofski, Lasse Jørgensen; Kruse, Anders; Magnusdottir, Sigriður Olga

    2018-01-01

    while the left control eye was given an identical injection without an implant. Fifteen days after BRVO and DEX implant intervention the retinas were excised and analyzed with tandem mass tag based mass spectrometry. A total of 26 significantly changed proteins were identified. Dexamethasone...... following an intervention with a dexamethasone (DEX) implant this study combined an experimental model of BRVO with proteomic techniques. In six Danish Landrace pigs experimental BRVO was induced in both eyes using argon laser. After inducing BRVO a DEX implant was injected in the right eye of each animal......-α and caveolin-1 were confirmed with immunohistochemistry. DEX implant intervention may inhibit PDGF signaling by decreasing the retinal level of PDGFR-α while an increased content of caveolin-1 may help maintain the integrity of the blood-retinal barrier....

  13. Applied biomechanics to evaluate the properties of laser beam treated orthopedic implants; Biomêcanica aplicada na avaliação de propriedades de implantes ortopédicos metálicos tratados por feixe laser

    Energy Technology Data Exchange (ETDEWEB)

    Pieretti, Eurico Felix

    2016-07-01

    Laser beam marking is used to ensure biomaterials’ identification and traceability. The texturing imparts greater adhesion to the surfaces of implantable medical devices. The aim of this work was to evaluate the surface behaviour of the austenitic stainless steel ABNT NBR ISO 5832-1 marked and textured by optical fiber laser beam using selected parameters, changing the pulse frequency; in face of its biomechanical behaviour, through tests of tensile strength, fatigue and wear; verify the localized corrosion susceptibility by electrochemical tests in a solution that simulates the body fluids; and analyze microstructural changes. The treatments performed altered the biomaterials roughness and their micro hardness as a function of the increase of the pulse frequency. The microstructure and chemical composition of the surfaces underwent changes that directly affected the passive layer of the stainless steels, triggering the corrosion process. This effect was evidenced by SVET, XPS and characterization of electronic properties of the passive film by the Mott-Schottky technique. These two types of laser treatments increased the surfaces' magnetic susceptibility. The parameters used for the marking and texturing did not induce a decrease in the cellular viability of the samples, as no cytotoxicity was showed even after prolonged incubation. This biomaterial was adequate on the biomechanical tests, since the laser treatments, under the conditions used, did not induce the formation of surface tensions of magnitude capable of leading the fatigue fracture, indicating infinite fatigue life; the region of fracture by tension could not be related to the laser marking. The wear volume decreased as a function of the increase in micro hardness produced by the increase of the pulse frequency in the texturing. The visual character of the markings and texturing was assured after the majority of the tests performed. (author)

  14. Prefabrication of a vascularized nerve graft by vessel implantation: preliminary report of an experimental model.

    Science.gov (United States)

    Cavadas, P C; Vera-Sempere, F J

    1994-01-01

    Regeneration through vascularized nerve grafts (VNG) seems to be better than nonvascularized nerve grafts (NVNG), especially in hostile beds. We report on an experimental technique of prefabrication of VNG by direct vessel implantation. An arteriovenous fistula was created in the groin region with autologous vein grafts in the Wistar rat model, and implanted into the sciatic nerve. Five weeks later the sciatic VNG was elevated on the prefabricated pedicle. The flap was free-transferred orthotopically over a silicone sheet to impede plasmatic imbibition. Flap viability at 3 days was complete. India ink injection of the AV fistula resulted in capillary ink filling within the nerve and surrounding tissues. Histologic sections of the flap were examined, revealing its neovascularity. In an ongoing study, the regeneration through this prefabricated VNG is being compared to native VNG.

  15. The effects of hydroxyapatite coating and bone allograft on fixation of loaded experimental primary and revision implants.

    Science.gov (United States)

    Søballe, Kjeld; Mouzin, Olivier R G; Kidder, Louis A; Overgaard, Søren; Bechtold, Joan E

    2003-06-01

    We used our established experimental model of revision joint replacement to examine the roles of hydroxyapatite coating and bone graft in improving the fixation of revision implants. The revision protocol uses the Søballe micromotion device in a preliminary 8-week period of implant instability for the presence of particulate polyethylene. During this procedure, a sclerotic endosteal bone rim forms, and a dense fibrous membrane is engendered, having macrophages with ingested polyethylene and high levels of inflammatory cytokines. At the time of revision after 8 weeks, the cavity is revised with either a titanium alloy (Ti) or a hydroxyapatite (HA) 6.0 mm plasma-sprayed implant, in the presence or absence of allograft packed into the initial 0.75 mm peri-implant gap. The contralateral limb is subjected to primary surgery with the same implant configuration, and serves as control. 8 implants were included in each of the 8 treatment groups (total 64 implants in 32 dogs). The observation period was 4 weeks after revision. Outcome measures are based on histomorphometry and mechanical pushout properties. The revision setting was always inferior to its primary counterpart. Bone graft improved the revision fixation in all treatment groups, as also did the HA coating. The sole exception was revision-grafted HA implants, which reached the same fixation as primary Ti and HA grafted implants. The revision, which was less active in general, seems to need the dual stimulation of bone graft and HA implant surface, to obtain the same level of fixation associated with primary implants. Our findings suggest that the combination of HA implant and bone graft may be of benefit in the clinical revision implant setting.

  16. Implant surface preparation in the surgical treatment of experimental peri-implantitis with autogenous bone graft and ePTFE membrane in cynomolgus monkeys

    DEFF Research Database (Denmark)

    Schou, Søren; Holmstrup, Palle; Jørgensen, Torben

    2003-01-01

    peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology......peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology...

  17. Orthopedic radiology in the postoperative patient (practical orthopedic radiology)

    International Nuclear Information System (INIS)

    Weissman, B.N.; Gelman, M.I.

    1987-01-01

    This course examines various aspects of the radiologic examination of postoperative orthopedic patients. The operative indications, pertinent aspects of surgical technique, expected postoperative radiographic appearances, and radiographic findings indicating postoperative complications are discussed. The evaluation of total joint replacement surgery, spinal surgery, lower extremity procedures, and failed orthopedic devices and appliances are covered

  18. Experimental and numerical study of cemented bone-implant interface behaviour

    Directory of Open Access Journals (Sweden)

    P. Zlamal

    2011-01-01

    Full Text Available Although the total hip replacement (THR is a long-proven method of surgical treatment of diseases and disorders of the human hip, the surgery brings some risk of long-term instability of the joint. The aim of the research was to investigate the cemented bone-implant interface behavior. The main problems (cement layer degradation and bone-cement interface debonding during physiological loading conditions have been investigated using a custom hip simulator. The experimental setup was designed to allow cyclic loading of the sample of pelvic bone with implanted cemented acetabular component. The hip contact force of required direction and magnitude was applied to the implant using a spherical femoral component head. The most unfavorable activity (downstairs walking was simulated. The process of damage accumulation in the fixation was monitored by repeated scanning using high resolution micro Computed Tomography (µCT. Use of micro-focus source and large high-resolution flat panel detector allows investigation of structural changes and crack propagation both in the cement layer and the trabecular bone.

  19. Orthopedic X-ray diagnostics

    International Nuclear Information System (INIS)

    Bernau, A.

    1982-01-01

    Positioning techniques have been developed as a means of standardizing skeleton pictures so as to facilitate functional interpretations in orthopedics. Standard positions are described as well as specific orthopedic and traumatological problems. The list of positions must, of course, be incomplete as there are too many. Access to the subject is facilitated by a systematic approach. (orig.) [de

  20. Experimental studies of thorium ion implantation from pulse laser plasma into thin silicon oxide layers

    Science.gov (United States)

    Borisyuk, P. V.; Chubunova, E. V.; Lebedinskii, Yu Yu; Tkalya, E. V.; Vasilyev, O. S.; Yakovlev, V. P.; Strugovshchikov, E.; Mamedov, D.; Pishtshev, A.; Karazhanov, S. Zh

    2018-05-01

    We report the results of experimental studies related to implantation of thorium ions into thin silicon dioxide by pulsed plasma flux expansion. Thorium ions were generated by laser ablation from a metal target, and the ionic component of the laser plasma was accelerated in an electric field created by the potential difference (5, 10 and 15 kV) between the ablated target and a SiO2/Si (0 0 1) sample. The laser ablation system installed inside the vacuum chamber of the electron spectrometer was equipped with a YAG:Nd3  +  laser having a pulse energy of 100 mJ and time duration of 15 ns in the Q-switched regime. The depth profile of thorium atoms implanted into the 10 nm thick subsurface areas together with their chemical state as well as the band gap of the modified silicon oxide at different conditions of implantation processes were studied by means of x-ray photoelectron spectroscopy and reflected electron energy loss spectroscopy methods. Analysis of the chemical composition showed that the modified silicon oxide film contains complex thorium silicates. Depending on the local concentration of thorium atoms, the experimentally established band gaps were located in the range 6.0–9.0 eV. Theoretical studies of the optical properties of the SiO2 and ThO2 crystalline systems were performed by ab initio calculations within hybrid functional. The optical properties of the SiO2/ThO2 composite were interpreted on the basis of the Bruggeman effective medium approximation. A quantitative assessment of the yield of isomeric nuclei in ‘hot’ laser plasma at the early stages of expansion was performed. The estimates made with experimental results demonstrated that the laser implantation of thorium ions into the SiO2 matrix can be useful for further research of low-lying isomeric transitions in a 229Th isotope with energy of 7.8 +/- 0.5 eV.

  1. Evaluation on the movement of endosseous titanium implants under continuous orthodontic forces: an experimental study in the dog.

    Science.gov (United States)

    Hsieh, Yao-Dung; Su, Ching-Ming; Yang, Yi-Hsin; Fu, Earl; Chen, Hui-Lin; Kung, Suefang

    2008-06-01

    The purpose of this study was to evaluate the movement of pure titanium implants under different continuous forces in the edentulous alveolar ridge. Four pairs of titanium implants were inserted into the right maxillary and mandibular post-extraction edentulous ridge of the experimental dog. Three different levels of continuous force (100, 200, and 500 g) were loaded onto three pairs of adjacent implant abutments using a memory Ni-Ti coil spring for up to 6 months and the remaining two implant abutments as the control group received no force. The positions of implant abutments were observed and the distances between the implants abutment at the top, middle and base levels were measured at the 0th, 2nd, 3rd, 6th and 8th month of the follow-up period. There was no significant change in the distances between adjacent abutments loaded with 100 or 200 g continuous forces throughout the entire study period. However, significantly more movement of implant abutments was noted in the 500 g pair after the 3rd month of loading when compared with the 200 or the 100 g pair (both P < 0.001). This change further increased at the 6th month (P < 0.001, 0.01, respectively). Moreover, the difference in the measurements at the top, middle and base level indicated that the two adjacent implants moved in a tipping manner in the 500 g pair after 3 and 6 months of loading. The osseointegrated implants remained stable and rigid with a pulling force of 100 and 200 g after 6 months of loading. However, when the force reached 500 g, the implants moved in an inward-tipping pattern. The results suggested that endosseous titanium implants might not necessarily be rigid anchorages under all circumstances.

  2. Comparison of two dental implant surface modifications on implants with same macrodesign: an experimental study in the pelvic sheep model.

    Science.gov (United States)

    Ernst, Sabrina; Stübinger, Stefan; Schüpbach, Peter; Sidler, Michéle; Klein, Karina; Ferguson, Stephen J; von Rechenberg, Brigitte

    2015-08-01

    The aim of this study was to compare two different surfaces of one uniform macro-implant design in order to focus exclusively on the osseointegration properties after 2, 4 and 8 weeks and to discuss the animal model chosen. In six mature sheep, n = 36 implants with a highly crystalline and phosphate-enriched anodized titanium oxide surface (TiU) and n = 36 implants with a hydrophilic, sandblasted, large grit and acid-etched surface (SLA) were placed in the pelvic bone. TiU implants were custom-made to match the SLA implant design. The implant stability and bone-to-implant contact (BIC) were assessed by resonance frequency (ISQ), backscatter scanning electron microscopy (B-SEM), light microscopy (LM), micro-CT and intravital fluorochrome staining. Biomechanical removal torque testing was performed. Overall, no statistically significant differences in BIC total (trabecular + cortical) between TiU and SLA were found via LM and B-SEM. BIC values (B-SEM; LM) in both groups revealed a steady rise in trabecular bone attachment to the implant surface after 2, 4 and 8 weeks. In the 2- to 4-week time interval in the TiU group (P = 0.005) as well as in the SLA group (P = 0.01), a statistically significant increase in BIC trabecular could be observed via LM. B-SEM values confirmed the statistically significant increase for TiU (P = 0.001). In both groups, BIC trabecular values after 8 weeks were significantly higher (P ≤ 0.05) than after 2 weeks (B-SEM; LM). Biomechanical data confirmed the histological data. The two surfaces proved comparable osseointegration in this sheep model. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. CT and MRI techniques for imaging around orthopedic hardware

    Energy Technology Data Exchange (ETDEWEB)

    Do, Thuy Duong; Skornitzke, Stephan; Weber, Marc-Andre [Heidelberg Univ. (Germany). Dept. of Clinical Radiology; Sutter, Reto [Uniklinik Balgrist, Zurich (Switzerland). Radiology

    2018-01-15

    Orthopedic hardware impairs image quality in cross-sectional imaging. With an increasing number of orthopedic implants in an aging population, the need to mitigate metal artifacts in computed tomography and magnetic resonance imaging is becoming increasingly relevant. This review provides an overview of the major artifacts in CT and MRI and state-of-the-art solutions to improve image quality. All steps of image acquisition from device selection, scan preparations and parameters to image post-processing influence the magnitude of metal artifacts. Technological advances like dual-energy CT with the possibility of virtual monochromatic imaging (VMI) and new materials offer opportunities to further reduce artifacts in CT and MRI. Dedicated metal artifact reduction sequences contain algorithms to reduce artifacts and improve imaging of surrounding tissue and are essential tools in orthopedic imaging to detect postoperative complications in early stages.

  4. Transcatheter aortic value implantation with self-expandable nitinol valved stent: an experimental study in sheep

    International Nuclear Information System (INIS)

    Jiang Haibin; Huang Xinmiao; Bai Yuan

    2011-01-01

    Objective: to determine the feasibility and safety of transcatheter aortic valve implantation with domestic self-expandable nitinol valved stent in experimental sheep. Methods: A fresh pig pericardium was cross-linked with a 0.6% glutaraldehyde solution for 36 hours and then sutured on a nitinol self-expandable stent. Ten healthy sheep of (46.00±2.60) kg body weight were chosen for the study. Under general anesthesia, the device was delivered through catheter into the native aortic valve of the sheep via the femoral artery or abdominal aorta. The animals were followed up for three months. Results: Six devices were successfully delivered at the desired position in six sheep with no occurrence of complications. Angiographic and hemodynamic studies confirmed that the stents were fixed at correct position with competent valve function immediately and 90 days after the procedure. Technical failure or fatal complications occurred in the remaining four sheep. Conclusion: Implantation of a domestic nitinol self-expandable stent at the aortic valve position through a transcatheter approach is feasible in experimental sheep. (authors)

  5. Healing of experimental femoral defects in rats after implantation of collagen-calcium phosphate biocomposites

    Directory of Open Access Journals (Sweden)

    O. V. Korenkov

    2017-06-01

    Full Text Available The aim of this study was to investigate the healing process of experimental defects of the femoral shaft diaphysis of rats after implantation of osteoplastic material Collapan into its cavity. In experi-mental animals, a perforated defect with diameter of 2.5 mm was created in the medullary canal of the femoral shaft and filled with osteoplastic material Collapan. In control rats, the defect was left un-filled. The bone fragments were examined on the 15th and 30th day by light microscopy morphometry and scanning electron microscopy. It was found that application of osteoplastic material Collapan in the femoral diaphysis defect optimised reparative osteogenesis, showed high biocompatibility, osteo-conductive properties, resorption ability and good integration with tissue-specific structures of the regenerate

  6. Development and implantation of application systems for reduction and analysis of experimental data in Nuclear Physics area

    International Nuclear Information System (INIS)

    Cardoso Junior, J.L.; Schelin, H.R.; Lemos, B.J.K.C.; Tanaka, E.H.; Castro, A.T.C.G.

    1984-01-01

    Several application systems for reduction and analysis of experimental data are described. These codes were development and/or implanted in tee IEAv/CTA CYBER 170/750 system. A brief description of the experimental data acquisition modes and the necessary reduction for analysis is given. Information on the purposes, uses and access of the codes are given [pt

  7. The influence of Young's modulus of loaded implants on bone remodeling: an experimental and numerical study in the goat knee.

    NARCIS (Netherlands)

    Stoppie, N.; Oosterwyck, H. Van; Jansen, J.A.; Wolke, J.G.C.; Wevers, M.; Naert, I.

    2009-01-01

    The aim of this study was to examine the influence of the Young's modulus of the implant material on the bone remodeling in a loaded condition. A combined animal experimental and computational study was set up. The animal experimental group comprised of 16 Saanen goats, each receiving one titanium

  8. Synthetic, implantable polymers for local delivery of IUdR to experimental human malignant glioma

    International Nuclear Information System (INIS)

    Williams, Jeffery A.; Yuan Xuan; Dillehay, Larry E.; Shastri, Venkatram R.; Brem, Henry; Williams, Jerry R.

    1998-01-01

    Purpose: Recently, polymeric controlled delivery of chemotherapy has been shown to improve survival of patients with malignant glioma. We evaluated whether we could similarly deliver halogenated pyrimidines to experimental intracranial human malignant glioma. To address this issue we studied the in vitro release from polymers and the in vivo drug delivery of IUdR to experimental human U251 glioblastoma xenografts. Methods and Materials: In vitro: To measure release, increasing (10%, 30%, 50%) proportions of IUdR in synthetic [(poly(bis(p-carboxyphenoxy)-propane) (PCPP):sebacic acid (SA) polymer discs were serially incubated in buffered saline and the supernatant fractions were assayed. In vivo: To compare local versus systemic delivery, mice bearing flank xenografts had intratumoral or contralateral flank IUdR polymer (50% loading) treatments. Mice bearing intracranial (i.c.) xenografts had i.c. versus flank IUdR polymer treatments. Four or 8 days after implantation of polymers, mice were sacrificed and the percentage tumor cells that were labeled with IUdR was measured using quantitative microscopic immunohistochemistry. Results: In vitro: Increasing percentage loadings of IUdR resulted in higher percentages of release: 43.7 + 0.1, 70.0 + 0.2, and 90.2 + 0.2 (p < 0.001 ANOVA) for the 10%, 30%, and 50% loadings, respectively. In vivo: For the flank tumors, both the ipsilateral and contralateral IUdR polymers resulted in similarly high percentages labeling of the tumors versus time. For the ipsilateral IUdR polymers, the percentage of tumor cellular labeling after 4 days versus 8 days was 45.8 ± 7.0 versus 40.6 ± 3.9 (p = NS). For the contralateral polymer implants, the percentage of tumor cellular labeling were 43.9 ± 10.1 versus 35.9 ± 5.2 (p = NS) measured 4 days versus 8 days after implantation. For the i.c. tumors treated with extracranial IUdR polymers, the percentage of tumor cellular labeling was low: 13.9 ± 8.8 and 11.2 ± 5.7 measured 4 and 8 days

  9. Biomechanical evaluation of one-piece and two-piece small-diameter dental implants: In-vitro experimental and three-dimensional finite element analyses.

    Science.gov (United States)

    Wu, Aaron Yu-Jen; Hsu, Jui-Ting; Chee, Winston; Lin, Yun-Te; Fuh, Lih-Jyh; Huang, Heng-Li

    2016-09-01

    Small-diameter dental implants are associated with a higher risk of implant failure. This study used both three-dimensional finite-element (FE) simulations and in-vitro experimental tests to analyze the stresses and strains in both the implant and the surrounding bone when using one-piece (NobelDirect) and two-piece (NobelReplace) small-diameter implants, with the aim of understanding the underlying biomechanical mechanisms. Six experimental artificial jawbone models and two FE models were prepared for one-piece and two-piece 3.5-mm diameter implants. Rosette strain gauges were used for in-vitro tests, with peak values of the principal bone strain recorded with a data acquisition system. Implant stability as quantified by Periotest values (PTV) were also recorded for both types of implants. Experimental data were analyzed statistically using Wilcoxon's rank-sum test. In FE simulations, the peak value and distribution of von-Mises stresses in the implant and bone were selected for evaluation. In in-vitro tests, the peak bone strain was 42% lower for two-piece implants than for one-piece implants. The PTV was slightly lower for one-piece implants (PTV = -6) than for two-piece implants (PTV = -5). In FE simulations, the stresses in the bone and implant were about 23% higher and 12% lower, respectively, for one-piece implants than those for two-piece implants. Due to the higher peri-implant bone stresses and strains, one-piece implants (NobelDirect) might be not suitable for use as small-diameter implants. Copyright © 2016. Published by Elsevier B.V.

  10. Results of bone regenerate study after osteosynthesis with bioinert and calcium phosphate-coated bioactive implants in experimental femoral neck fractures (experimental study

    Directory of Open Access Journals (Sweden)

    K. S. Kazanin

    2015-01-01

    Full Text Available Objective - to analyze the results of X-ray, cytomorphometric and immunohistochemistry experimental studies of bone regenerates after osteosynthesis with bioinert and calcium phosphate-coated bioactive implants. Material and methods. The study was conducted on experimental femoral neck fractures in rabbit males. Reparative osteogenesis processes were studied in groups of bioinert titanium implant osteosynthesis and calcium phosphate-coated bioactive titanium implant osteosynthesis. The animals were clinically followed-up during the postoperative period. X-ray, cytomorphometric and immunohistochemistry studies of samples extracted from femoral bones were conducted over time on days 1, 7, 14, 30 and 60. The animal experiments were kept and treated according to recommendations of international standards, Helsinki Declaration on animal welfare and approved by the local ethics committee. All surgeries were performed under anesthesia, and all efforts were made to minimize the suffering of the animals. Results. In the animal group without femoral neck fracture osteosynthesis, femoral neck pseudoarthrosis was observed at the end of the experiment. The results of cytomorphometric and immunohistochemistry studies conducted on day 60 of the experiment confirmed that the cellular composition of the bone regenerate in the group of calcium phosphate-coated bioactive titanium implants corresponded to a more mature bone tissue than in the group of bioinert titanium implants. Conclusion. The results of the statistical analysis of cytomorphometric and immunohistochemistry data show that the use of calcium phosphate-coated bioactive titanium implants allows to achieve significantly earlier bone tissue regeneration.

  11. Bone Morphometric Evaluation around Immediately Placed Implants Covered with Porcine-Derived Pericardium Membrane: An Experimental Study in Dogs

    Directory of Open Access Journals (Sweden)

    Ryo Jimbo

    2012-01-01

    Full Text Available Objective. To investigate whether porcine-derived bioresorbable pericardium membrane coverage enhances the osseointegration around implants placed in fresh extraction sockets. Study Design. Twenty-four commercially available endosseous implants were placed in the fresh extraction sockets of the mandibular first molar of mature beagles (. On one side, implants and osteotomy sites were covered with porcine-derived bioresorbable pericardium membranes, whereas on the other side, no membranes were used. After 6 weeks, samples were retrieved and were histologically processed for histomorphometric analysis. Results. The histological observation showed that bone loss and soft tissue migration in the coronal region of the implant were evident for the control group, whereas bone fill was evident up to the neck of the implant for the membrane-covered group. Bone-to-implant contact was significantly higher for the membrane-covered group compared to the control group, 75% and 45% (, respectively. Conclusion. The experimental membranes proved to regenerate bone around implants placed in fresh extraction sockets without soft tissue intrusion.

  12. Slow drilling speeds for single-drill implant bed preparation. Experimental in vitro study.

    Science.gov (United States)

    Delgado-Ruiz, R A; Velasco Ortega, E; Romanos, G E; Gerhke, S; Newen, I; Calvo-Guirado, J L

    2018-01-01

    To evaluate the real-time bone temperature changes during the preparation of the implant bed with a single-drill protocol with different drill designs and different slow drilling speeds in artificial type IV bone. For this experimental in vitro study, 600 implant bed preparations were performed in 10 bovine bone disks using three test slow drilling speeds (50/150/300 rpm) and a control drilling speed (1200 rpm). The temperature at crestal and apical areas and time variations produced during drilling with three different drill designs with similar diameter and length but different geometry were recorded with real-life thermographic analysis. Statistical analysis was performed by two-way analysis of variance. Multiple comparisons of temperatures and time with the different drill designs and speeds were performed with the Tukey's test. T Max values for the control drilling speed with all the drill designs (D1 + 1200; D2 + 1200; D3 + 1200) were higher compared to those for the controls for 11 ± 1.32 °C (p drilling at 50 rpm resulted in the lowest temperature increment (22.11 ± 0.8 °C) compared to the other slow drilling speeds of 150 (24.752 ± 1.1 °C) and 300 rpm (25.977 ± 1.2 °C) (p drilling speeds compared to that for the control drilling speed. Slow drilling speeds required significantly more time to finish the preparation of the implant bed shown as follows: 50 rpm > 150 rpm > 300 rpm > control (p drill protocol with slow drilling speeds (50, 150, and 300 rpm) without irrigation in type IV bone increases the temperature at the coronal and apical levels but is below the critical threshold of 47 °C. The drill design in single-drill protocols using slow speeds (50, 150, and 300 rpm) does not have an influence on the thermal variations. The time to accomplish the implant bed preparation with a single-drill protocol in type IV bone is influenced by the drilling speed and not by the drill design. As the speed decreases, then

  13. Greening of orthopedic surgery.

    Science.gov (United States)

    Lee, Rushyuan J; Mears, Simon C

    2012-06-01

    Every year, 4 billion pounds of waste are produced by health care facilities, and the amount continues to increase annually. In response, a movement toward greening health care has been building, with a particular focus on the operating room. Between 20% and 70% of health care waste originates from a hospital's operating room, and up to 90% of operating room waste is improperly sorted and sent for costly and unneeded hazardous waste processing. Recent successful changes include segregation of hospital waste, substitution of the ubiquitous polypropylene plastic wrap used for the sterilization and handling of surgical equipment with metal cases, and the reintroduction of reusable surgical gowns. Orthopedic-related changes include the successful reprocessing and reuse of external fixators, shavers, blades, burs, and tourniquets. These changes have been shown to be environmentally and economically beneficial. Early review indicates that these changes are feasible, but a need exists for further evaluation of the effect on the operating room and flow of the surgical procedure and of the risks to the surgeons and operating room staff. Other key considerations are the effects of reprocessed and reused equipment on patient care and outcome and the role of surgeons in helping patients make informed decisions regarding surgical care. The goals of this study were to summarize the amount and types of waste produced in hospitals and operating rooms, highlight the methods of disposal used, review disposal methods that have been developed to reduce waste and improve recycling, and explore future developments in greening health care. Copyright 2012, SLACK Incorporated.

  14. Effect of titanium dental implants on proton therapy delivered for head tumors: experimental validation using an anthropomorphic head phantom

    Science.gov (United States)

    Oancea, C.; Shipulin, K.; Mytsin, G.; Molokanov, A.; Niculae, D.; Ambrožová, I.; Davídková, M.

    2017-03-01

    A dosimetric experiment was performed at the Medico-Technical Complex in the Joint Institute for Nuclear Research, Dubna, to investigate the effects of metallic dental implants in the treatment of head and neck tumours with proton therapy. The goal of the study was to evaluate the 2D dose distributions of different clinical treatment plans measured in an anthropomorphic phantom, and compare them to predictions from a treatment planning system. The anthropomorphic phantom was sliced into horizontal segments. Two grade 4 Titanium implants were inserted between 2 slices, corresponding to a maxillary area. GafChromic EBT2 films were placed between the segments containing the implants to measure the 2D delivered dose. Two different targets were designed: the first target includes the dental implants in the isocentre, and in the second target, the proton beam is delivered through the implants, which are located at the entrance region of the Bragg curve. The experimental results were compared to the treatment plans made using our custom 3D Treatment Planning System, named RayTreat. To quantitatively determine differences in the isodose distributions (measured and calculated), the gamma index (3 mm, 3%) was calculated for each target for the matrix value in the region of high isodose (> 90%): for the experimental setup, which includes the implants in the SOBP region, the result obtained was 84.3%. When the implants were localised in the entrance region of the Bragg curve, the result obtained was 86.4%. In conclusion, the uncertainties introduced by the clinically planned dose distribution are beyond reasonable limits. The linear energy transfer spectra in close proximity to the implants were investigated using solid state nuclear track detectors (TED). Scattered particles outside the target were detected.

  15. Effect of titanium dental implants on proton therapy delivered for head tumors: experimental validation using an anthropomorphic head phantom

    International Nuclear Information System (INIS)

    Oancea, C.; Shipulin, K.; Mytsin, G.; Molokanov, A.; Niculae, D.; Ambrožová, I.; Davídková, M.

    2017-01-01

    A dosimetric experiment was performed at the Medico-Technical Complex in the Joint Institute for Nuclear Research, Dubna, to investigate the effects of metallic dental implants in the treatment of head and neck tumours with proton therapy. The goal of the study was to evaluate the 2D dose distributions of different clinical treatment plans measured in an anthropomorphic phantom, and compare them to predictions from a treatment planning system. The anthropomorphic phantom was sliced into horizontal segments. Two grade 4 Titanium implants were inserted between 2 slices, corresponding to a maxillary area. GafChromic EBT2 films were placed between the segments containing the implants to measure the 2D delivered dose. Two different targets were designed: the first target includes the dental implants in the isocentre, and in the second target, the proton beam is delivered through the implants, which are located at the entrance region of the Bragg curve. The experimental results were compared to the treatment plans made using our custom 3D Treatment Planning System, named RayTreat. To quantitatively determine differences in the isodose distributions (measured and calculated), the gamma index (3 mm, 3%) was calculated for each target for the matrix value in the region of high isodose (> 90%): for the experimental setup, which includes the implants in the SOBP region, the result obtained was 84.3%. When the implants were localised in the entrance region of the Bragg curve, the result obtained was 86.4%. In conclusion, the uncertainties introduced by the clinically planned dose distribution are beyond reasonable limits. The linear energy transfer spectra in close proximity to the implants were investigated using solid state nuclear track detectors (TED). Scattered particles outside the target were detected.

  16. Is Salvage of Recently Infected Breast Implant After Breast Augmentation or Reconstruction Possible? An Experimental Study.

    Science.gov (United States)

    Castus, P; Heymans, O; Melin, P; Renwart, L; Henrist, C; Hayton, E; Mordon, S; Leclère, F M

    2018-04-01

    The reinsertion of an infected implant when peri-prosthetic infection occurs early after breast augmentation or breast reconstruction remains controversial. In this experimental study, the authors tried to remove bacteria, and their biofilm, from the colonized surface of breast prostheses, without damaging their integrity. A total of 112 shell samples of silicone breast prostheses, smooth (SPSS) and textured (TPSS), were colonized by S. epidermidis (SE) or S. aureus (SA) strains, all able to produce biofilms. After 15 days, all the samples were removed from the contaminated culture broth and constituted 4 groups of 20 contaminated samples: SPSS/SE (group I), SPSS/SA (group II), TPSS/SE (group III), TPSS/SE (group IV). In another group-group SEM-, 16 colonized samples were used for documentation with scanning electron microscopy (SEM). The remaining 16 samples were used to test the limits of detection of the sterility test. All samples of groups I-IV and 8 samples of group SEM were « washed » with a smooth brush in a povidone-iodine bath and rinsed with saline solution. A subset of the washed samples was sent for SEM and the others were immersed in sterile broth and were incubated at 35 °C for 3 weeks (groups I-IV). Fifteen days after contamination, all the samples in groups I-IV were colonized. In the SEM group, SEM images attested to the presence of bacteria in biofilm attached to the shells. After cleaning, SEM did not reveal any bacteria and there was no visible alteration in the outer structure of the shell. Sterility tests performed after decontamination in groups I-IV remained negative for all the samples. Breast prostheses recently contaminated with Staphylococci, frequently involved in peri-prosthetic breast implant infection and capable of producing biofilms, can be efficiently decontaminated by the procedure used in this study. Our decontamination procedure did not alter the surface structure of the prostheses. This decontamination procedure

  17. Managing orthopedics and neurosciences costs through standard treatment protocols.

    Science.gov (United States)

    McGinnity, E S; Pluth, T E

    1994-06-01

    High-cost, high-volume specialty programs such as orthopedics and neurosciences find themselves in a position of evaluating the costs and in some cases the appropriateness of medical practices in response to payer scrutiny and provider selection processes. Orthopedics and neurosciences programs are at a stage of development analogous to that of cardiovascular care several years ago. Many of the same trends have come into play, such as payer "carve-outs" for orthopedic services, payer selection of centers of excellence based on cost and quality, reduction of Medicare reimbursement, greater use of high-cost technology, the decline of profitability due to "older, sicker, and tougher" patients, and the recent emergence of national orthopedic specialty networks oriented to national contracts for care. In an era in which payers demand value on both sides of the cost-plus-quality equation, programs are challenged to maximize the return on a patient population rife with "no-win" situations. In the orthopedic service line these include a high proportion of Medicare patients and chronic conditions such as workers' compensation medical back cases or repetitive motion injuries, which can be elusive to diagnose and expensive to treat. Many hospitals continue to lose money on joint replacement surgeries, the largest-volume orthopedic inpatient service, primarily because of the high Medicare population and the cost of implants. Neuroservices, while still relatively well reimbursed, face a rising proportion of Medicare payments as patients live longer and develop chronic, degenerative conditions. Inpatient days are decreasing due to payer pressures to limit hospital stays and to shift inpatient care to outpatient services. Some hospitals "have lost interest in (the orthopedic) service line during the last five years because of recent trends in orthopedic-related inpatient volume and payment." But by managing costs strategically, both the neurosciences and orthopedics service lines

  18. The effect of interstitial 125I seeds implantation on intestinal wall: a pathological observation in experimental dogs

    International Nuclear Information System (INIS)

    Ning Houfa; Zhang Fenglian; Shen An; Cao Guiwen; Cui Xinjiang

    2010-01-01

    Objective: To observe the radiation injury of the bowel wall due to the implantation of interstitial 125 I seeds in experimental dogs. Methods: A total of 12 healthy male dogs were randomly and equally divided into 3 experimental groups and 1 control group, with 3 dogs in each group.In the experimental groups, two 125 I seeds with the active radiation dose of 0.8mCi were symmetrically implanted under the serous membrane of the dog's small intestinal wall. The dogs were fed for 14 days (group A), for one month (group B) and for two months (group C) respectively when the animals were scheduled to be sacrificed. The dogs' general condition was observed till they were sacrificed. The seed-implanting intestinal segments were then removed and dyed with HE staining method for electronic microscopic exam. The histopathologic findings were recorded and the results were compared between four groups. Results: No obvious histopathological changes were found in the dog's bowel wall 14 days after the implantation. One month after the procedure cellular injury was observed under electronic microscope, and two months after the operation partial fibrosis of the intestinal wall appeared but no ulceration or perforation occurred. Conclusion: The implantation of 125 I seeds can cause reversible cellular injuries of the intestinal wall in experimental dogs, the degree of the damage reaches its peak at one month after the implant when the partial fibrosis of bowel wall becomes evident. However, the seeds do not cause any serious complications, such as ulceration or perforation. (authors)

  19. Biodegradable Orthopedic Magnesium-Calcium (MgCa Alloys, Processing, and Corrosion Performance

    Directory of Open Access Journals (Sweden)

    Yuebin Guo

    2012-01-01

    Full Text Available Magnesium-Calcium (Mg-Ca alloy has received considerable attention as an emerging biodegradable implant material in orthopedic fixation applications. The biodegradable Mg-Ca alloys avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. They also provide sufficient mechanical strength in load carrying applications as opposed to biopolymers. However, the key issue facing a biodegradable Mg-Ca implant is the fast corrosion in the human body environment. The ability to adjust degradation rate of Mg-Ca alloys is critical for the successful development of biodegradable orthopedic implants. This paper focuses on the functions and requirements of bone implants and critical issues of current implant biomaterials. Microstructures and mechanical properties of Mg-Ca alloys, and the unique properties of novel magnesium-calcium implant materials have been reviewed. Various manufacturing techniques to process Mg-Ca based alloys have been analyzed regarding their impacts on implant performance. Corrosion performance of Mg-Ca alloys processed by different manufacturing techniques was compared. In addition, the societal and economical impacts of developing biodegradable orthopedic implants have been emphasized.

  20. Experimental and computational analysis of micromotions of an uncemented femoral knee implant using elastic and plastic bone material models

    NARCIS (Netherlands)

    Berahmani, Sanaz; Janssen, Dennis; Verdonschot, Nico

    2017-01-01

    It is essential to calculate micromotions at the bone-implant interface of an uncemented femoral total knee replacement (TKR) using a reliable computational model. In the current study, experimental measurements of micromotions were compared with predicted micromotions by Finite Element Analysis

  1. Experimental and numerical study of cemented bone-implant interface behaviour

    Czech Academy of Sciences Publication Activity Database

    Kytýř, Daniel; Doktor, Tomáš; Jiroušek, Ondřej; Zlámal, Petr; Pokorný, D.

    2011-01-01

    Roč. 15, č. 15 (2011), s. 5-13 ISSN 1971-8993 R&D Projects: GA ČR(CZ) GAP105/10/2305 Institutional research plan: CEZ:AV0Z20710524 Keywords : bone-cement interface * computed tomography * hip simulator * crack detection Subject RIV: FI - Traumatology, Orthopedics http://www.gruppofrattura.it/index.php?option=com_content&task=view&id=90&Itemid=284

  2. Medical photography: principles for orthopedics.

    Science.gov (United States)

    Uzun, Metin; Bülbül, Murat; Toker, Serdar; Beksaç, Burak; Kara, Adnan

    2014-04-05

    Medical photography is used clinically for patient evaluation, treatment decisions, and scientific documentation. Although standards for medical photography exist in many branches of medicine, we have not encountered such criteria in publications in the area of orthopedics. This study aims to (1) assess the quality of medical images used in an orthopedic publication and (2) to propose standards for medical photography in this area. Clinical photographs were reviewed from all issues of a journal published between the years 2008 and 2012. A quality of clinical images was developed based on the criteria published for the specialties of dermatology and cosmetic surgery. All images were reviewed on the appropriateness of background, patient preparation, and technique. In this study, only 44.9% of clinical images in an orthopedic publication adhered to the proposed conventions. Standards have not been established for medical photography in orthopedics as in other specialty areas. Our results suggest that photographic clinical information in orthopedic publications may be limited by inadequate presentation. We propose that formal conventions for clinical images should be established.

  3. [Significance of various implantate localizations of Sparks prostheses, experimental studies in rats].

    Science.gov (United States)

    Brieler, H S; Parwaresch, R; Thiede, A

    1976-01-01

    Our investigations show that Sparks prostheses after subcutaneous implantation are suitable for vascular grafting. At the end of the organization period the connective tissue becomes strong, and after the third and fourth weeks collagenous and elastic fibers can be seen. Ten weeks after s.c. implantation, collagenous fibers predominate. After this the Sparks prostheses can be used as a vascular graft. Intraperitoneal implantation, however, shows a histologically different picture with characteristic findings: only fat cells can be observed, a strong granulation tissue with elastic and collagenous fibers is not present. After intraperitoneal implantation Sparks prostheses are therefore unsuitable for vascular grafts.

  4. Correlation of experimental damage data for the development of the UT-MARLOWE Monte Carlo ion implant simulator

    International Nuclear Information System (INIS)

    Morris, M. F.; Tian, S.; Chen, Y.; Tasch, A.; Baumann, S.; Kirchhoff, J. F.; Hummel, R.; Prussin, S.; Kamenitsa, D.; Jackson, J.

    1999-01-01

    The Monte Carlo ion implant simulator UT-MARLOWE has usually been verified using a large array of Secondary Ion Mass Spectroscopy (SIMS) data (∼200 profiles per ion species)(1). A model has recently been developed (1) to explicitly simulate defect production, diffusion, and their interactions during the picosecond 'defect production stage' of ion implantation. In order to thoroughly validate this model, both SIMS and various damage measurements were obtained (primarily channeling-Rutherford Backscattering Spectroscopy, Differential Reflectometry and Tapered Groove Profilometry, but supported with SEM and XTEM data). In general, the data from the various experimental techniques was consistent, and the Kinetic Accumulation Damage Model (KADM) was developed and validated using this data. This paper discusses the gathering of damage data in conjunction with SIMS in support of the development of an ion implantation simulator

  5. Imaging of orthopedic sports injuries

    International Nuclear Information System (INIS)

    Vanhoenacker, F.M.; Gielen, J.L.; Maas, M.

    2007-01-01

    This volume provides an updated review of imaging abnormalities in orthopedic sports injuries. The first part of the book contains background information on relevant basic science and general imaging principles in sports traumatology. The second part comprises a topographic discussion of sports injuries. Each chapter highlights the merit of different imaging techniques, focused on a specific clinical problem. In the third part, natural history, monitoring and follow-up by imaging are discussed. This well-illustrated book will be of value for musculoskeletal radiologists, orthopedic surgeons, sports physicians and everyone else involved in sports medicine. (orig.)

  6. Artificial implantation materials; Sztuczne materialy implantacyjne

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowska-Szumiel, M [Akademia Medyczna, Warsaw (Poland)

    1997-10-01

    The radiation techniques for sterilization of orthopedic materials and high performance biomaterials have been reviewed. The radiation formulation of synthetic biomaterials for implantation and other medical use have been also performed. 18 refs, 3 tabs.

  7. Pectin nanocoating of titanium implant surfaces - an experimental study in rabbits

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna Aleksandra; Dirscherl, Kai; Jørgensen, Bodil

    2017-01-01

    that may increase adhesion of bone proteins, and bone cells at the implant surface. Nanocoating with pectins, plant cell wall-derived polysaccharides, is frequently done using rhamnogalacturonan-I (RG-I). AIM: The aim of the study was to evaluate the effect of nanocoating titanium implants with plant cell...... wall-derived rhamnogalacturonan-I, on bone healing and osseointegration. MATERIAL AND METHODS: Machined titanium implants were coated with three modifications of rhamnogalacturonan-I (RG-I). Chemical and physical surface properties were examined before insertion of nanocoated implants (n = 96....... The bone response to the nanocoated implants was analyzed qualitatively and quantitatively after 2, 4, 6, and 8 weeks of healing using light microscopy and histomorphometric methods. RESULTS: The RG-I coating influenced the surface chemical composition; wettability and roughness, making the surface more...

  8. Osteoporotic rat models for evaluation of osseointegration of bone implants

    NARCIS (Netherlands)

    Alghamdi, H.S.A.; Beucken, J.J.J.P van den; Jansen, J.A.

    2014-01-01

    Osseointegration of dental and orthopedic bone implants is the important process that leads to mechanical fixation of implants and warrants implant functionality. In view of increasing numbers of osteoporotic patients, bone implant surface optimization strategies with instructive and drug-loading

  9. Relationship of microstructure to fracture topography in orthopedic alloys

    International Nuclear Information System (INIS)

    Gilbertson, L.N.

    1976-01-01

    Two major alloys used for orthopedic implants are 316L stainless steel and a cast cobalt--chromium--molybdenum alloy similar to Haynes Stellite 21. Another alloy that is just being introduced is Ti--6Al--4V. All three of these alloys are used in different conditions with different microstructures. Standard specimens with typical microstructures encountered in orthopedic applications were loaded to fracture in both overload and fatigue modes. Different rates of loading were also used in some cases. The fracture surfaces of these standard samples were analyzed in the Scanning Electron Microscope. An attempt was made to relate the fracture behavior, as evidenced by the fracture typography, to the microstructure of the alloy as revealed by metallography

  10. Histologic Changes of Implanted Gore Bio-A in an Experimental Animal Model

    Directory of Open Access Journals (Sweden)

    Kwan Koo Yeo

    2014-01-01

    Full Text Available Gore Bio-A has been reported to be an ideal synthetic bioabsorbable scaffold material for hernia repair. The purpose of this study was to determine the effectiveness of Gore Bio-A in soft tissue augmentation. Six New Zealand white rabbits were used in the study. Five subcutaneous pockets were created on the back of the rabbit, and 20×20 mm sized square shaped Gore Bio-A sheets, each 1.5 mm, 3 mm, 4.5 mm, 6 mm, and 7.5 mm in thickness, were implanted into each pocket (1 layer to 5 layers. To analyze the morphologic and histologic changes, the implants were harvested 1, 3, and 6 months after implantation. Following the gross analysis, absorption rate was accelerated with increased implant duration and decreased thickness. Histological analysis of the implants demonstrated progressive neovascularization, fibroblast infiltration, and neocollagenation over time. Six months after implantation, Gore Bio-A was almost absorbed and degenerated, not maintaining its volume. Based on this study, Gore Bio-A was revealed as a biocompatible material; however, it is not suitable for soft tissue augmentation because it is absorbed in the process of changing into soft tissue without maintaining its own volume. Therefore, this material is incomplete and needs more study to overcome this limitation.

  11. Comparison of experimental target currents with analytical model results for plasma immersion ion implantation

    International Nuclear Information System (INIS)

    En, W.G.; Lieberman, M.A.; Cheung, N.W.

    1995-01-01

    Ion implantation is a standard fabrication technique used in semiconductor manufacturing. Implantation has also been used to modify the surface properties of materials to improve their resistance to wear, corrosion and fatigue. However, conventional ion implanters require complex optics to scan a narrow ion beam across the target to achieve implantation uniformity. An alternative implantation technique, called Plasma Immersion Ion Implantation (PIII), immerses the target into a plasma. The ions are extracted from the plasma directly and accelerated by applying negative high-voltage pulses to the target. An analytical model of the voltage and current characteristics of a remote plasma is presented. The model simulates the ion, electron and secondary electron currents induced before, during and after a high voltage negative pulse is applied to a target immersed in a plasma. The model also includes analytical relations that describe the sheath expansion and collapse due to negative high voltage pulses. The sheath collapse is found to be important for high repetition rate pulses. Good correlation is shown between the model and experiment for a wide variety of voltage pulses and plasma conditions

  12. [Carbon fiber-reinforced plastics as implant materials].

    Science.gov (United States)

    Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R

    2003-01-01

    Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

  13. Selective laser melting porous metallic implants with immobilized silver nanoparticles kill and prevent biofilm formation by methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    van Hengel, Ingmar A. J.; Riool, Martijn; Fratila-Apachitei, Lidy E.; Witte-Bouma, Janneke; Farrell, Eric; Zadpoor, Amir A.; Zaat, Sebastian A. J.; Apachitei, Iulian

    2017-01-01

    Implant-associated infection and limited longevity are two major challenges that orthopedic devices need to simultaneously address. Additively manufactured porous implants have recently shown tremendous promise in improving bone regeneration and osseointegration, but, as any conventional implant,

  14. Osseointegration of dental implants in extraction sockets preserved with porous titanium granules - an experimental study.

    Science.gov (United States)

    Verket, Anders; Lyngstadaas, Ståle P; Rønold, Hans J; Wohlfahrt, Johan C

    2014-02-01

    This study investigated osseointegration of dental implants inserted in healed extraction sockets preserved with porous titanium granules (PTG). Three adult female minipigs (Gøttingen minipig; Ellegaard A/S, Dalmose, Denmark) had the mandibular teeth P2, P3 and P4 extracted. The extraction sockets were preserved with metallic PTG (Tigran PTG; Tigran Technologies AB, Malmö, Sweden) n = 12, heat oxidized white porous titanium granules (WPTG) (Tigran PTG White) n = 12 or left empty (sham) n = 6. All sites were covered with collagen membranes (Bio-Gide; Geistlich Pharma, Wolhausen, Switzerland) and allowed 11 weeks of healing before implants (Straumann Bone Level; Straumann, Basel, Switzerland) were inserted. The temperature was measured during preparation of the osteotomies. Resonance frequency analysis (RFA, Osstell; Osstell AB, Gothenburg, Sweden) was performed at implant insertion and at termination. After 6 weeks of submerged implant healing, the pigs were euthanized and jaw segments were excised for microCT and histological analyses. In the temperature and RFA analyses no significant differences were recorded between the test groups. The microCT analysis demonstrated an average bone volume of 61.7% for the PTG group compared to 50.3% for the WPTG group (P = 0.03) and 57.1% for the sham group. Histomorphometry demonstrated an average bone-to-implant contact of 68.2% for the PTG group compared to 36.6% for the WPTG group and 60.9% for the sham group (n.s). Eight out of ten implants demonstrated apical osseous defects in the WPTG group, but similar defects were observed in all groups. PTG preserved extraction sockets demonstrate a similar outcome as the sham control group for all analyses suggesting that this material potentially can be used for extraction socket preservation prior to implant installment. Apical osseous defects were however observed in all groups including the sham group, and a single cause could not be determined. © 2012 John Wiley & Sons A/S.

  15. Machining of a bioactive nanocomposite orthopedic fixation device.

    Science.gov (United States)

    Sparnell, Amie; Aniket; El-Ghannam, Ahmed

    2012-08-01

    Bioactive ceramics bond to bone and enhance bone formation. However, they have poor mechanical properties which restrict their machinability as well as their application as load bearing implants. The goal of this study was to machine bioactive fixation screws using a silica-calcium phosphate nanocomposite (SCPC50). The effect of compact pressure, holding time, and thermal treatment on the microstructure, machinability, and mechanical properties of SCPC50 cylinders were investigated. Samples prepared by powder metallurgy technique at compact pressure range of 100-300 MPa and treated at 900°C/1 h scored a poor machinability rating of (1/5) due to the significant formation of amorphous silicate phase at the grain boundaries. On the other hand, lowering of compact pressure and sintering temperature to 30 MPa/3 h and 700°C/2 h, respectively, minimized the formation of the amorphous phase and raised the machinability rating to (5/5). The modulus of elasticity and ultimate strength of machinable SCPC50 were 10.8 ± 2.0 GPa and 72.8 ± 22.8 MPa, respectively, which are comparable to the corresponding values for adult human cortical bone. qRT-PCR analyses showed that bone cells attached to SCPC50 significantly upregulated osteocalcin mRNA expression as compared to the cells on Ti-6Al-4V. Moreover, cells attached to SCPC50 produced mineralized bone-like tissue within 8 days. On the other hand, cells attached to Ti-6Al-4V failed to produce bone mineral under the same experimental conditions. Results of the study suggest that machinable SCPC50 has the potential to serve as an attractive new material for orthopedic fixation devices. Copyright © 2012 Wiley Periodicals, Inc.

  16. Experimental conical-head abutment screws on the microbial leakage through the implant-abutment interface: an in vitro analysis using target-specific DNA probes.

    Science.gov (United States)

    Pita, Murillo S; do Nascimento, Cássio; Dos Santos, Carla G P; Pires, Isabela M; Pedrazzi, Vinícius

    2017-07-01

    The aim of this in vitro study was to identify and quantify up to 38 microbial species from human saliva penetrating through the implant-abutment interface in two different implant connections, external hexagon and tri-channel internal connection, both with conventional flat-head or experimental conical-head abutment screws. Forty-eight two-part implants with external hexagon (EH; n = 24) or tri-channel internal (TI; n = 24) connections were investigated. Abutments were attached to implants with conventional flat-head or experimental conical-head screws. After saliva incubation, Checkerboard DNA-DNA hybridization was used to identify and quantify up to 38 bacterial colonizing the internal parts of the implants. Kruskal-Wallis test followed by Bonferroni's post-tests for multiple comparisons was used for statistical analysis. Twenty-four of thirty-eight species, including putative periodontal pathogens, were found colonizing the inner surfaces of both EH and TI implants. Peptostreptococcus anaerobios (P = 0.003), Prevotella melaninogenica (P abutment screws have impacted the microbial leakage through the implant-abutment interface. Implants attached with experimental conical-head abutment screws showed lower counts of microorganisms when compared with conventional flat-head screws. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Estudo experimental da biocompatibilidade de novo material para implante orbitário

    Directory of Open Access Journals (Sweden)

    Rodrigo Beraldi Kormann

    2013-06-01

    Full Text Available OBJETIVO:Avaliar a biocompatibilidade de material FullCure 720®, que é uma resina, na confecção de implante orbitário. Avaliou-se a resposta clínica dos animais, toxicidade sistêmica e a resposta inflamatória crônica. Os animais foram pesados, exames bioquímicos e resposta inflamatória foram avaliados. Foi efetuada evisceração e colocado implante esférico orbitário. Os animais foram acompanhados durante o período de 60 dias, onde se avaliou o comportamento clínico e sinais locais. Após este período, procedeu-se a eutanásia seguida da enucleação. Foi realizada análise macroscópica e histomorfométrica. Os resultados revelaram comportamento normal dos animais, com ausência de exposição ou extrusão dos implantes, morte de algum animal e ausência de toxicidade sistêmica. Houve formação de uma cápsula fibrosa entre a capa escleral e o implante orbitário, resposta inflamatória considerada normal quando em contato com o tecido do coelho. A resina FullCure 720® utilizada como implante orbitário, mostrou-se biocompatível neste estudo.

  18. Implante Autólogo Ovariano no Omento Maior: Estudo Experimental Ovarian Autotransplantation to the Greater Omentum: Experimental Model

    Directory of Open Access Journals (Sweden)

    Luiz Ronaldo Alberti

    2002-01-01

    Full Text Available Objetivos: avaliar os aspectos morfofuncionais de ovários implantados no omento maior, bem como a melhor técnica para implantação do ovário: se íntegro ou fatiado. Métodos: foram divididas aleatoriamente 40 ratas Wistar com ciclos estrais normais em quatro grupos: Grupo I (n = 5, controle - laparotomia; Grupo II (n = 5, ooforectomia total bilateral; Grupo III (n = 15, implante autólogo íntegro no omento maior e Grupo IV (n = 15, implante autólogo fatiado no omento maior. Realizaram-se esfregaços vaginais nos 3º e 6º mes pós-operatório e estudos histológicos dos implantes ovarianos, avaliando-se: degeneração, fibrose, reação inflamatória, angiogênese, cistos foliculares, desenvolvimento folicular e corpos lúteos. Resultados: os animais do Grupo I ciclaram normalmente. As ratas do Grupo II não apresentaram ciclo, permanecendo em diestro. No Grupo III, 11 ratas permaneceram em diestro, três apresentaram ciclos incompletos e apenas uma ciclou normalmente. No Grupo IV, três animais não ciclaram, oito tiveram esfregaços vaginais incompletos e quatro ciclaram normalmente. Os achados histológicos dos animais pertencentes ao Grupo III evidenciaram histoarquitetura normal em dez ratas, porém nas outras cinco, houve degeneração ovariana. No Grupo IV, 14 ratas tiveram ovários com histoarquitetura preservada e em apenas uma houve sinais de degeneração. Conclusões: o implante autólogo ovariano no omento maior foi viável, obtendo-se melhor preservação morfofuncional com a implantação de fatias.Purpose: in order to maintain the gonadal function after oophorectomy, morphofunctional aspects of ovarian autotransplantation to the greater omentum and the best kind of implantation, intact or sliced, were investigated. Methods: forty cycling female Wistar rats were randomly divided into four groups: Group I (n = 5, control - laparotomy; Group II (n = 5, bilateral oophorectomy; Group III (n = 10, intact ovarian

  19. Reliable experimental setup to test the pressure modulation of Baerveldt Implant tubes for reducing post-operative hypotony

    Science.gov (United States)

    Ramani, Ajay

    Glaucoma encompasses a group of conditions that result in damage to the optic nerve and can cause loss of vision and blindness. The nerve is damaged due to an increase in the eye's internal (intraocular) pressure (IOP) above the nominal range of 15 -- 20 mm Hg. There are many treatments available for this group of diseases depending on the complexity and stage of nerve degradation. In extreme cases where drugs or laser surgery do not create better conditions for the patient, ophthalmologists use glaucoma drainage devices to help alleviate the IOP. Many drainage implants have been developed over the years and are in use; but two popular implants are the Baerveldt Glaucoma Implant and the Ahmed Glaucoma Valve Implant. Baerveldt Implants are non-valved and provide low initial resistance to outflow of fluid, resulting in post-operative complications such as hypotony, where the IOP drops below 5 mm of Hg. Ahmed Glaucoma Valve Implants are valved implants which initially restrict the amount of fluid flowing out of the eye. The long term success rates of Baerveldt Implants surpass those of Ahmed Valve Implants because of post-surgical issues; but Baerveldt Implants' initial effectiveness is poor without proper flow restriction. This drives the need to develop new ways to improve the initial effectiveness of Baerveldt Implants. A possible solution proposed by our research team is to place an insert in the Baerveldt Implant tube of inner diameter 305 microns. The insert must be designed to provide flow resistance for the early time frame [e.g., first 30 -- 60 post-operative days] until sufficient scar tissue has formed on the implant. After that initial stage with the insert, the scar tissue will provide the necessary flow resistance to maintain the IOP above 5 mm Hg. The main objective of this project was to develop and validate an experimental apparatus to measure pressure drop across a Baerveldt Implant tube, with and without inserts. This setup will be used in the

  20. Effect of plasma-rich in platelet-derived growth factors on peri-implant bone healing: An experimental study in canines

    Science.gov (United States)

    Birang, Reza; Torabi, Alireza; Shahabooei, Mohammad; Rismanchian, Mansour

    2012-01-01

    Background: Tissue engineering principles can be exploited to enhance alveolar and peri-implant bone reconstruction by applying such biological factors as platelet-derived growth factors. The objective of the present study is to investigate the effect of autologous plasma-rich in growth factors (on the healing of peri-implant bone in canine mandible). Materials and Methods: In this prospective experimental animal study, two healthy canines of the Iranian mix breed were selected. Three months after removing their premolar teeth on both sides of the mandible, 12 implants of the Osteo Implant Corporationsystem, 5 mm in diameter and 10 mm in length, were selected to be implanted. Plasma rich in growth factors (PRGF) were applied on six implants while the other six were used as plain implants without the plasma. The implants were installed in osteotomy sites on both sides of the mandible to be removed after 4 weeks with the surrounding bones using a trephine bur. Mesio-distal sections and implant blocks, 50 μ in diameter containing the peri-implant bone, were prepared By basic fuchin toluidine-bluefor histological and histomorphometric evaluation by optical microscope. The data were analyzed using Mann-Whitney Test (PPRGF and control groups had no statistically significant differences (P=0.261, P=0.2) although the parameters showed higher measured values in the PRGF group. However, compared to the control, application of PRGF had significantly increased bone-to-implant contact (P=0.028) Conclusion: Based on the results, it may be concluded that application of PRGF on the surface of implant may enhance bone-to-implant contact. PMID:22363370

  1. Anchorage of titanium implants with different surface characteristics: an experimental study in rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2000-01-01

    ) TiO2-blasted with particles of grain size 10 to 53 microns; (3) TiO2-blasted, grain size 63 to 90 microns; (4) TiO2-blasted, grain size 90 to 125 microns; (5) titanium plasma-sprayed (TPS). The surface topography was determined by the use of an optical instrument. Twelve rabbits, divided into two...... groups, had a total of 120 implants inserted in the tibiae. One implant from each of the five surface categories was placed within the left tibia of each rabbit. By a second operation, implants were installed in the right tibia, after 2 weeks in group A and after 3 weeks in group B. Fluorochrome labeling...

  2. Experimental and numerical research of mechanical behaviour of titanium alloy hip implant

    Czech Academy of Sciences Publication Activity Database

    Čolić, K.; Sedmak, A.; Legweel, K.; Milošević, M.I.; Nitrović, N.; Mišković, Ž.; Hloch, Sergej

    2017-01-01

    Roč. 24, č. 3 (2017), s. 709-713 ISSN 1330-3651 Institutional support: RVO:68145535 Keywords : biomedical implant * digital image correlation * finite element method * Ti-6Al-4V alloy Subject RIV: JQ - Machines ; Tools OBOR OECD: Mechanical engineering Impact factor: 0.723, year: 2016 https://hrcak.srce.hr/index.php?id_clanak_jezik=269849&show=clanak

  3. No effect of hydroxyapatite particles in phagocytosable sizes on implant fixation: an experimental study in dogs

    DEFF Research Database (Denmark)

    Rahbek, O; Kold, S; Bendix, K

    2005-01-01

    particles (n = 8), or (4) hyaluronic acid and PE particles (n = 8). After 4 weeks, the animals were killed. The implant interface was evaluated by pushout testing until failure and by histomorphometry. Both HA and PE particles were found to be phagocytosed by macrophage-like cells in the interfacial tissue...

  4. Bone tissue engineering for spine fusion : An experimental study on ectopic and orthotopic implants in rats

    NARCIS (Netherlands)

    van Gaalen, SM; Dhert, WJA; van den Muysenberg, A; Oner, FC; van Blitterswijk, C; Verbout, AJ; de Bruijn, J.D.

    2004-01-01

    Alternatives to the use of autologous bone as a bone graft in spine surgery are needed. The purpose of this study was to examine tissue-engineered bone constructs in comparison with control scaffolds without cells in a posterior spinal implantation model in rats. Syngeneic bone marrow cells were

  5. Osseointegration and biocompatibility of different metal implants - a comparative experimental investigation in sheep

    Science.gov (United States)

    2012-01-01

    Background In the present study, 4 different metallic implant materials, either partly coated or polished, were tested for their osseointegration and biocompatibility in a pelvic implantation model in sheep. Methods Materials to be evaluated were: Cobalt-Chrome (CC), Cobalt-Chrome/Titanium coating (CCTC), Cobalt-Chrome/Zirconium/Titanium coating (CCZTC), Pure Titanium Standard (PTST), Steel, TAN Standard (TANST) and TAN new finish (TANNEW). Surgery was performed on 7 sheep, with 18 implants per sheep, for a total of 63 implants. After 8 weeks, the specimens were harvested and evaluated macroscopically, radiologically, biomechanically (removal torque), histomorphometrically and histologically. Results Cobalt-Chrome screws showed significantly (p = 0.031) lower removal torque values than pure titanium screws and also a tendency towards lower values compared to the other materials, except for steel. Steel screws showed no significant differences, in comparison to cobalt-chrome and TANST, however also a trend towards lower torque values than the remaining materials. The results of the fluorescence sections agreed with those of the biomechanical test. Histomorphometrically, there were no significant differences of bone area between the groups. The BIC (bone-to-implant-contact), used for the assessment of the osseointegration, was significantly lower for cobalt-chrome, compared to steel (p = 0.001). Steel again showed a lower ratio (p = 0.0001) compared to the other materials. Conclusion This study demonstrated that cobalt-chrome and steel show less osseointegration than the other metals and metal-alloys. However, osseointegration of cobalt-chrome was improved by zirconium and/or titanium based coatings (CCTC, TANST, TAN, TANNEW) being similar as pure titanium in their osseointegrative behavior. PMID:22400715

  6. EXPERIMENTAL RESEARCH OF REGENERATIVE FEATURES IN BONE TISSUES AROUND IMPLANTS AFTER ONE-STAGE BILATERAL TOTAL HIP REPLACEMENT

    Directory of Open Access Journals (Sweden)

    V. M. Mashkov

    2012-01-01

    Full Text Available Objective: to research the specific features of regenerative processes of bone tissue around implants after one-stage bilateral total hip replacement in experiment. Material and methods: 27 total hip replacement operations have been performed in 18 rabbits of breed "chinchilla" to which bipolar femoral endoprosthesis made of titanic alloy PT-38, one type-size, with friction pair metal-on-metal and neck-shaft angle 165 degrees have been implanted: total unilateral hip replacement operations have been performed in 9 animals (control group, one-stage bilateral total hip replacement operations have been performed in 9 animals (experimental group. During research they have been on radiological and clinical checking-up. After the experiment the animals had histological tests of the tissues around endoprosthesis components. Results and conclusions: After one-stage bilateral total hip replacement in early terms of research more expressed changes of bone tissue in the form of its thinning and decompaction were found around implants. One-stage bilateral total hip replacement did not essentially influence on the speed of osteogenesis around endoprothesis components in comparison with unilateral total hip replacement, so in late terms of observation in both groups the fixing of endoprothesis components did not differ.

  7. Experimental substantiation of the design of a prosthetic heart valve for «valve-in-valve» implantation

    Directory of Open Access Journals (Sweden)

    K. Yu. Klyshnikov

    2017-01-01

    Full Text Available The aim of the study was to perform a series of in vitro tests of a prototype of the developing heart valve prosthesis to evaluate its functional characteristics. Materials and methods. In this work we have used the frames and full prototypes of the prosthesis, consisting of a stent-like stainless steel support frame with mounted biological leaflets and cover. The authors evaluated the calculated and experimental forces necessary for the displacement of the sutureless implanted prosthesis using the test machine under uniaxial tension. The risk of defects and damages to the supporting framework as a result of implantation was evaluated by scanning electron microscopy. The hydrodynamic characteristics of the prosthesis were investigated under physiological conditions and «valvein-valve» implantation. Evaluation of the ergonomics and applicability of the proposed construction on the cadaver heart model of cattle was carried out. Results. As a result of the forces assessment, it was found that the force required to shear the prosthesis was 3.12 ± 0.37 N, while the calculated value was 1.7 N, which is significantly lower than the obtained value. The comparison of the images obtained with small and large magnifications demonstrated the absence of critical surface defects. Additional analysis under the super-large magnifications also did not reveal problem areas. During the hydrodynamic study, it was shown that the average transplant gradient increased slightly from 2.8–3.4 to 3.2–4.5 mm Hg for the initial prosthesis and the «valve-in-valve» complex, respectively. The decrease of the effective orifice area was 6–9% relative to the initial one. Evaluation of the implantation technique demonstrated the consistency of the approach: the use of the developed holder in combination with the balloon implantation system made it possible to position the prosthesis throughout the procedure. Conclusion. The series of tests demonstrates the consistency

  8. Histomorphometric and removal torque analysis for TiO2-blasted titanium implants. An experimental study on dogs

    DEFF Research Database (Denmark)

    Gotfredsen, K; Nimb, L; Hjörting-Hansen, E

    1992-01-01

    The aim of the present study was to compare the anchorage of TiO2-blasted screw and cylindrical implants with conventionally used machine-produced screw and cylindrical implants inserted immediately in extraction sockets on dogs. 6 adult mongrel dogs had 3rd and 4th mandibular premolars extracted...... bilaterally and 24 commercial pure titanium implants were placed immediately in extraction sockets and covered with mucoperiosteum. Each dog had inserted 4 implants: 1 screw implant and 1 cylindrical implant blasted with titanium-dioxide-particles; 1 screw implant and 1 cylindrical implant with machine...

  9. Wholistic orthopedics: Is this the right way to treat geriatric orthopedic patients?

    OpenAIRE

    John Ebnezar; Yogita Bali; Rakesh John

    2017-01-01

    Geriatric orthopedic problems poses different challenges in their management. Conventional treatment methods like drugs, physiotherapy and surgeries are inadequate. A Geriatric orthopedic patient suffers as a whole and not in isolation. This article highlights the importance of managing geriatric orthopedic patients as a whole and outlines the various steps of wholistic management.

  10. Wholistic orthopedics: Is this the right way to treat geriatric orthopedic patients?

    Directory of Open Access Journals (Sweden)

    John Ebnezar

    2017-01-01

    Full Text Available Geriatric orthopedic problems poses different challenges in their management. Conventional treatment methods like drugs, physiotherapy and surgeries are inadequate. A Geriatric orthopedic patient suffers as a whole and not in isolation. This article highlights the importance of managing geriatric orthopedic patients as a whole and outlines the various steps of wholistic management.

  11. Nanotechnology: the scope and potential applications in orthopedic surgery.

    Science.gov (United States)

    Gavaskar, Ashok; Rojas, D; Videla, F

    2018-03-30

    Nanotechnology involves manipulation of matter measuring 1-100 nm in at least one of its dimensions at the molecular level. Engineering and manipulation of matter at the molecular level has several advantages in the field of medicine (nanomedicine) since most of the biological molecules exist and function at a nanoscale. Though promising, questions still remain on how much of this will ultimately translate into achieving better patient care. Concerns of cost-effectiveness and nanotechnology safety still remain unclear. Orthopedics is an attractive area for the application of nanotechnology since the bone, and its constituents such as hydroxyapatite, Haversian systems, and the collagen fibrils are nanocompounds. The major orthopedic applications of nanotechnology involve around (i) effective drug delivery systems for antibiotics and chemotherapeutic agents, (ii) surface preparation of implants and prosthesis to improve osteointegration and reduce biofilm formation, (iii) controlled drug eluting systems to combat implant-related infections, (iv) tissue engineering for scaffolds preparation to deal with bone and cartilage defects, and (v) diagnostic applications in the field of oncology and musculoskeletal infections.

  12. Zirconium, calcium, and strontium contents in magnesium based biodegradable alloys modulate the efficiency of implant-induced osseointegration

    Science.gov (United States)

    Mushahary, Dolly; Sravanthi, Ragamouni; Li, Yuncang; Kumar, Mahesh J; Harishankar, Nemani; Hodgson, Peter D; Wen, Cuie; Pande, Gopal

    2013-01-01

    Development of new biodegradable implants and devices is necessary to meet the increasing needs of regenerative orthopedic procedures. An important consideration while formulating new implant materials is that they should physicochemically and biologically mimic bone-like properties. In earlier studies, we have developed and characterized magnesium based biodegradable alloys, in particular magnesium-zirconium (Mg-Zr) alloys. Here we have reported the biological properties of four Mg-Zr alloys containing different quantities of strontium or calcium. The alloys were implanted in small cavities made in femur bones of New Zealand White rabbits, and the quantitative and qualitative assessments of newly induced bone tissue were carried out. A total of 30 experimental animals, three for each implant type, were studied, and bone induction was assessed by histological, immunohistochemical and radiological methods; cavities in the femurs with no implants and observed for the same period of time were kept as controls. Our results showed that Mg-Zr alloys containing appropriate quantities of strontium were more efficient in inducing good quality mineralized bone than other alloys. Our results have been discussed in the context of physicochemical and biological properties of the alloys, and they could be very useful in determining the nature of future generations of biodegradable orthopedic implants. PMID:23976848

  13. Sequential healing at implants installed immediately into extraction sockets. An experimental study in dogs.

    Science.gov (United States)

    Mainetti, Tomaso; Lang, Niklaus P; Bengazi, Franco; Favero, Vittorio; Soto Cantero, Luis; Botticelli, Daniele

    2016-01-01

    To compare the sequential healing at implants installed in a healed alveolar bony ridge or immediately after tooth extraction without functional load. In the mandible of 12 dogs, the mesial roots of the first molars were endodontically treated, the tooth hemisected, and the distal roots extracted. After 3 months, the mesial roots of the fourth premolars were endodontically treated, the tooth hemisected, and the distal roots extracted in one side of the mandible. Implants were placed immediately into extraction sockets (IPIES) of the fourth premolar and in the healed sites in the molar regions. Healing abutments were placed, and the flaps were sutured to allow a non-submerged healing. The time of surgery and of sacrifices were planned in such a way to obtain biopsies representing the healing after 1 and 2 weeks and 1 and 3 months, respectively. Ground sections were prepared for histological evaluation of tissues components on the implant surface and the coronal termination level of osseointegration (M-B). New bone apposition on the implant surface was slightly higher at the healed compared to the IPIES sites, being 7.4% and 4.1% after 1 week, and 67.3% and 65.3% after 3 months, respectively. Old bone was progressively resorbed, from 27.0% and 21.9% after 1 week, to 2.5% and 2.0% after 3 months, at healed and IPIES sites, respectively. M-B was 1.4 mm and 2.6 mm after 1 week, 1.2 mm and 1.2 mm after 3 months, at healed and IPIES sites, respectively. Similar patterns of sequential osseointegration were found at implants installed in healed alveolar bone or in alveolar sockets immediately after tooth extraction. The coronal termination level of osseointegration, that was different after 1 week, was found similar at the 3-month observation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Physicians founders of orthopedic surgery in Serbia

    Directory of Open Access Journals (Sweden)

    Bumbaširević Marko

    2004-01-01

    Full Text Available The beginnings of the development of orthopedic surgery in Serbia have been related to the name of Dr Nikola Krstic and his first radiography of the hand in 1908. The foundation of the Orthopedic Ward, led by Dr Nikola Krstic, within the General State Hospital in Belgrade, in 1919, marks the definition of orthopedics as a separate branch of surgery. In addition to Dr Nikola Krstic, Dr Borivoje Lalovic and Temp. Docent Dr Borivoje Gradojevic, who published the first orthopedics textbook in Serbian in 1934, also worked at the orthopedic ward between the two world wars. The work at the orthopedic ward, which grew into a clinic in 1947, was continued by Prof. Dr Milos Simovic, Prof. Dr Svetislav Stojanovic and Prof, dr Ljubisa Boric. Their successors would have high achievements: Prof. Dr Zivojin Bumbasirevic became the only orthopedist who was a regular member of the Serbian Academy of Sciences and Arts, and Chief of Staff Dr Predrag Klisic and Prof. Dr Branko Radulovic provide impetus for further development of orthopedics by founding Specialist Orthopedics Hospital "Banjica".

  15. Imaging of orthopedic trauma and surgery

    International Nuclear Information System (INIS)

    Berquist, T.H.

    1986-01-01

    This book bridges the communication gap, between the radiologist and the orthopedic surgeon in regard to trauma. It also combines ease of use with authoritative information, and includes in each discussion a review of the pertinent anatomy, mechanism of injury, and radiology and orthopedic classification

  16. [Experimental study on vascular bundle implantation combined with cellular transplantation in treating rabbit femoral head necrosis].

    Science.gov (United States)

    Chen, Shuang-Tao; Zhang, Wei-Ping; Liu, Chang-An; Wang, Jun-Jiang; Song, Heng-Yi; Chai, Zhi-wen

    2013-03-01

    To discuss the feasibility of vascular bundle implantation combined with allogeneic bone marrow stromal cells (BMSCs) transplantation in treating rabbit femoral head osteonecrosis and bone defect, in order to explore a new method for the treatment of femoral head necrosis. Thirty-six New Zealand rabbits were randomly divided into three groups,with 12 rabbits in each group. Bilateral femoral heads of the rabbits were studied in the experiment. The models were made by liquid nitrogen frozen, and the femoral heads were drilled to cause bone defect. Group A was the control group,group B was stem cells transplantaion group of allograft marrow stromal,and group C was stem cells transplantation group of allograft marrow stromal combined with vascular bundle implantation. Three rabbits of each group were sacrificed respectively at 2, 4, 8, 12 weeks after operation. All specimens of the femoral heads were sliced for HE staining. Furthermore ,vascular density and the percentage of new bone trabecula of femoral head coronary section in defect area were measured and analyzed statistically. In group C,new bone trabecula and original micrangium formed at the 2nd week after operation; new bone trabecula was lamellar and interlaced with abundant micrangium at the 8th week;at the 12th week,the broadened,coarsened bone trabecula lined up regularly,and the mature bone trabecula and new marrow were visible. At the 2nd week after operation,there was no statistical significance in the percentage of new bone trabecula of femoral head coronary section in defect area between group B and C. While at 4, 8, 12 week after operation, vascular density and the percentage of new bone trabecula of femoral head coronary section in defect area of group C was higher than that of group B. Allogeneic bone marrow stromal cells cultured in vivo can form new bone trabecula, and can be applied to allotransplant. Vascular bundle implanted into the bone defect area of femoral head necrosis could improve blood

  17. Enhanced osteoblast adhesion on nanostructured selenium compacts for anti-cancer orthopedic applications

    Directory of Open Access Journals (Sweden)

    Phong Tran

    2008-10-01

    Full Text Available Phong Tran1, Thomas J Webster21Physics Department; 2Division of Engineering and Department of Orthopedics, Brown University, Providence, USAAbstract: Metallic bone implants possess numerous problems limiting their long-term efficacy, such as poor prolonged osseointegration, stress shielding, and corrosion under in vivo environments. Such problems are compounded for bone cancer patients since numerous patients receive orthopedic implants after cancerous bone resection. Unfortunately, current orthopedic materials were not originally developed to simultaneously increase healthy bone growth (as in traditional orthopedic implant applications while inhibiting cancerous bone growth. The long-term objective of the present research is to investigate the use of nano-rough selenium to prevent bone cancer from re-occurring while promoting healthy bone growth for this select group of cancer patients. Selenium is a well known anti-cancer chemical. However, what is not known is how healthy bone cells interact with selenium. To determine this, selenium, spherical or semispherical shots, were pressed into cylindrical compacts and these compacts were then etched using 1N NaOH to obtain various surface structures ranging from the micron, submicron to nano scales. Changes in surface chemistry were also analyzed. Through these etching techniques, results of this study showed that biologically inspired surface roughness values were created on selenium compacts to match that of natural bone roughness. Moreover, results showed that healthy bone cell adhesion increased with greater nanometer selenium roughness (more closely matching that of titanium. In this manner, this study suggests that nano-rough selenium should be further tested for orthopedic applications involving bone cancer treatment.Keywords: selenium, nano-rough, osteoblast, cancer, chemopreventive

  18. What expects orthopedic surgeon from bone scan?

    International Nuclear Information System (INIS)

    Sutter, B.; Cazenave, A.

    2003-01-01

    The isotope bone scan continues to be one of the 'lost widely performed nuclear medicine investigations. Beyond the common clinical indication like detection of skeletal metastases, bone scan use is increasing in benign orthopedic conditions, and after orthopedic surgery, despite development of new investigations modalities (US, MRI). Three (or two) phase bone scintigraphy, Single Photon Emission Computer Tomography have increased its value and provided new clinical roles. This review emphasizes through some practical clinical examples how to increase diagnostic value of the method and to offer an adapted response to the orthopedic surgeon's attempts. (author)

  19. Estudo experimental da aplicação do ventrículo artificial eletromecânico pulsátil implantável Experimental study of pulsatile implantable electromechanical artificial ventricle

    Directory of Open Access Journals (Sweden)

    Jarbas Jakson Dinkhuysen

    2011-03-01

    Full Text Available OBJETIVO: Apresentar os resultados da aplicação deste dispositivo em animais de experimentação, promovendo auxílio hemodinâmico apenas ao ventrículo esquerdo (VE. MÉTODOS: Entre junho 2002 e outubro 2009, foram implantados em 27 bezerros com idade 2½ a 4 meses e peso 80/100 kg e, por meio de anestesia geral e ventilação controlada e de toracotomia lateral esquerda, era introduzida cânula no ápice do VE e anastomose término/lateral de tubo vascular de politetrafluoretileno (PTFE com a porção descendente da aorta torácica, ambos interligados ao dispositivo implantado no subcutâneo abaixo do diafragma (24 e intratorácico (três. Em cinco bezerros, o dispositivo foi aplicado com auxílio de circulação extracorpórea (CEC e, em 22, sem CEC. RESULTADOS: Ocorreram dois óbitos durante o implante e três por causas diversas nas primeiras horas de pós-operatório (PO, sendo um relacionado ao dispositivo. A sobrevivência entre o 1º e 6º dia de PO ocorreu em 17 animais e entre o 8º e 31º dia de PO em cinco, com causas determinantes diversas, não só por problemas clínico/cirúrgicos, mas também relacionados ao dispositivo. O impacto hemodinâmico avaliado pela análise da pressão sistêmica mostrou incremento que variou de 20 a 40 mmHg e os dados laboratoriais analisados demonstraram baixos impactos traumáticos à crase sanguínea e boa biocompatibilidade. CONCLUSÃO: Trata-se de pesquisa árdua e complexa onde a cada experimento são identificados problemas não só de implantabilidade, mas também relacionados ao dispositivo, que vão sendo sistematicamente corrigidos, tornando-o cada vez mais seguro e eficaz.OBJECTIVE: The objective is to present the results of the application this device in experimental animals unloading only the left ventricle. METHODS: Between June 2002 and October 2009, were implanted in 27 calfs with age between 2½ to 4 months and 80 to 100 kg of weight, with general anaesthesia and controled

  20. The implantation of separating aortic stent-graft into the canine thoracic aorta: an experimental study

    International Nuclear Information System (INIS)

    Xia Jinguo; Shi Haibin; Yang Zhengqiang; Li Chao; Liu Sheng; Zu Qingquan; Li Linsun

    2011-01-01

    Objective: to assess the technical feasibility of implanting separating stent-graft into the canine thoracic aorta and to study its biocompatibility. Methods: Twelve adult dogs were randomly and equally divided into three groups. The right femoral artery was cut open, through which the separating stent-graft was inserted and deployed in the canine thoracic aorta, with the proximal end of the graft being quite close to the origin of the left subclavian artery. the technical feasibility of the deployment process was assessed. Angiography was performed at 4, 8 and 12 weeks after stent-graft placement to evaluate the position and patency of the stent-graft. Then the dogs were sacrificed and the specimens were collected for pathologic study. Both gross and microscopic examinations were made to evaluate the fixation of the stent-graft with the vessel wall, the endothelialization of stent-graft surface and the pathologic changes of the vascular wall. Results: A total of ten separating stent-grafts were successfully deployed in the canine thoracic aorta, no migration or deformation occurred. One dog died of massive bleeding due to the rupture of the right femoral artery which occurred when the delivery system containing the inner bare stent was inserted through the right femoral artery. Death occurred in another dog as a result of the ascending aorta rupture caused by the migration of outer-layer stent-graft. Angiography was conducted at 4, 8 and 12 weeks after stent-graft placement. No migration, deformation, rupture or stenosis of the implanted stent-grafts were observed. The formation of intima on the inner surface of the bare stent appeared at 4 weeks, which became more and more obvious with the time passing, and at 12 weeks complete endothelialization of stent-graft surface was observed. Conclusion: Technically, it is feasible to deploy the separating aortic stent-graft into the canine thoracic aorta. Moreover, the separating aortic stent-graft carries excellent

  1. Cardiovascular effects of right ventricle-pulmonary artery valved conduit implantation in experimental pulmonic stenosis

    International Nuclear Information System (INIS)

    Saida, Y.; Tanaka, R.; Fukushima, R.; Hoshi, K.; Hira, S.; Soda, A.; Iizuka, T.; Ishikawa, T.; Nishimura, T.; Yamane, Y.

    2009-01-01

    Right ventricle (RV)-pulmonary artery (PA) valved conduit (RPVC) implantation decreases RV systolic pressure in pulmonic stenosis (PS) by forming a bypass route between the RV and the PA. The present study evaluates valved conduits derived from canine aortae in a canine model of PS produced by pulmonary artery banding (PAB). Pulmonary stenosis was elicited using PAB in 10 conditioned beagles aged 8 months. Twelve weeks after PAB, the dogs were assigned to one group that did not undergo surgical intervention and another that underwent RPVC using denacol-treated canine aortic valved grafts (PAB+RPVC). Twelve weeks later, the rate of change in the RV-PA systolic pressure gradient was significantly decreased in the PAB+RPVC, compared with the PAB group (60.5+-16.7% vs. 108.9+-22.9%; p0.01). In addition, the end-diastolic RV free wall thickness (RVFWd) was significantly reduced in the PAB+RPVC, compared with the PAB group (8.2+-0.2 vs. 9.4+-0.7 mm; p0.05). Thereafter, regurgitation was not evident beyond the conduit valve and the decrease in RV pressure overload induced by RPVC was confirmed. The present results indicate that RPVC can be performed under a beating heart without cardiopulmonary bypass and adapted to dogs with various types of PS, including 'supra valvular' PS or PS accompanied by dysplasia of the pulmonary valve. Therefore, we consider that this method is useful for treating PS in small animals

  2. Marginal bone-level alterations of loaded zirconia and titanium dental implants: an experimental study in the dog mandible.

    Science.gov (United States)

    Thoma, Daniel S; Benic, Goran I; Muñoz, Fernando; Kohal, Ralf; Sanz Martin, Ignacio; Cantalapiedra, Antonio G; Hämmerle, Christoph H F; Jung, Ronald E

    2016-04-01

    The aim was to test whether or not the marginal bone-level alterations of loaded zirconia implants are similar to the bone-level alterations of a grade 4 titanium one-piece dental implant. In six dogs, all premolars and the first molars were extracted in the mandible. Four months later, three zirconia implants (BPI, VC, ZD) and a control titanium one-piece (STM) implant were randomly placed in each hemimandible and left for transmucosal healing (baseline). Six months later, CAD/CAM crowns were cemented. Sacrifice was scheduled at 6-month postloading. Digital X-rays were taken at implant placement, crowns insertion, and sacrifice. Marginal bone-level alterations were calculated, and intra- and intergroup comparisons performed adjusted by confounding factors. Implants were successfully placed. Until crown insertion, two implants were fractured (one VC, one ZD). At sacrifice, 5 more implants were (partly) fractured (one BPI, four ZD), and one lost osseointegration (VC). No decementation of crowns occurred. All implant systems demonstrated a statistically significant (except VC) loss of marginal bone between baseline and crown insertion ranging from 0.29 mm (VC; P = 0.116) to 0.80 mm (ZD; P = 0.013). The estimated marginal bone loss between baseline and 6 months of loading ranged between 0.19 mm (BPI) and 1.11 mm (VC), being statistically significant for STM and VC only (P implants and control implants (STM vs. BPI P = 0.007; vs. VC P = 0.001; vs. ZD P = 0.011). Zirconia implants were more prone to fracture prior to and after loading with implant-supported crowns compared to titanium implants. Individual differences and variability in the extent of the bone-level changes during the 12-month study period were found between the different implant types and materials. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Anchorage of TiO2-blasted, HA-coated, and machined implants: an experimental study with rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Wennerberg, A; Johansson, C

    1995-01-01

    The purpose of this study was to evaluate the histometrical and biomechanical anchorage of TiO2-blasted implants and TiO2-blasted implants coated with hydroxyapatite. The control implants were machined. Twenty-six rabbits had a total of 156 implants placed in the proximal part of the tibia. Each...... rabbit had a machined, a TiO2-blasted, and a TiO2-blasted, HA-coated implant placed in each tibia. After a healing period of 3 and 12 weeks, respectively, the implants placed in the right tibia were used for removal torque test, and the implants placed in the left tibia were used for histomorphometrical...

  4. Design and Validation of Implantable Passive Mechanisms for Orthopedic Surgery

    Science.gov (United States)

    2017-10-01

    delamination was observed in some of the samples after soaking overnight in water . Delamination resulted in a non-uniform layer of coating. This...prognosis, treatment , and/or rehabilitation of a disease, injury or condition, or to improve the quality of life. Examples include: • data or...Muscle and Tendons. Biomedical Engineering, IEEE Transactions on, 62(9), 2208-2214. [3] G. N. O’Dell, Anatomy of the human grey body: grey anatomy

  5. Battlefield Acquired Immunogenicity to Metals Affects Orthopedic Implant Outcome

    Science.gov (United States)

    2013-10-01

    include minor bruising/hematoma (12.3%), diaphoresis with hypotension (2.6%), syncope (ə%), and cellulitis or phlebitis (ə%). Standard aseptic...Diaphoresis with hypotension (2.6%) • Syncope (ə%) • Cellulitis or Phlebitis (ə%) The following information will be collected for all AEs: • Date/time

  6. Experimental evaluation of an online gamma-camera imaging of permanent seed implantation (OGIPSI) prototype for partial breast irradiation

    International Nuclear Information System (INIS)

    Ravi, Ananth; Caldwell, Curtis B.; Pignol, Jean-Philippe

    2008-01-01

    Previously, our team used Monte Carlo simulation to demonstrate that a gamma camera could potentially be used as an online image guidance device to visualize seeds during permanent breast seed implant procedures. This could allow for intraoperative correction if seeds have been misplaced. The objective of this study is to describe an experimental evaluation of an online gamma-camera imaging of permanent seed implantation (OGIPSI) prototype. The OGIPSI device is intended to be able to detect a seed misplacement of 5 mm or more within an imaging time of 2 min or less. The device was constructed by fitting a custom built brass collimator (16 mm height, 0.65 mm hole pitch, 0.15 mm septal thickness) on a 64 pixel linear array CZT detector (eValuator-2000, eV Products, Saxonburg, PA). Two-dimensional projection images of seed distributions were acquired by the use of a digitally controlled translation stage. Spatial resolution and noise characteristics of the detector were measured. The ability and time needed for the OGIPSI device to image the seeds and to detect cold spots was tested using an anthropomorphic breast phantom. Mimicking a real treatment plan, a total of 52 103 Pd seeds of 65.8 MBq each were placed on three different layers at appropriate depths within the phantom. The seeds were reliably detected within 30 s with a median error in localization of 1 mm. In conclusion, an OGIPSI device can potentially be used for image guidance of permanent brachytherapy applications in the breast and, possibly, other sites

  7. Radiotherapy and risk of implantable cardioverter-defibrillator malfunctions: experimental data from direct exposure at increasing doses.

    Science.gov (United States)

    Zecchin, Massimo; Artico, Jessica; Morea, Gaetano; Severgnini, Mara; Bianco, Elisabetta; De Luca, Antonio; Fantasia, Anna Zorzin; Salvatore, Luca; Milan, Vittorino; Lucarelli, Matteo; Dissegna, Roberta; Cannatà, Antonio; Sinagra, Gianfranco

    2018-04-01

    During radiotherapy, in patients with implantable cardioverter-defibrillators (ICDs) malfunctions are considered more likely if doses more than 2 Gy reach the ICD site; however, most malfunctions occur with high-energy (>10 MV) radiations, and the risk is less defined using 6-MV linear accelerators. The purpose of the study is to experimentally evaluate the occurrence of malfunctions in ICDs radiated with a 6-MV linear accelerator at increasing photon doses. Thirty-two ICDs from all manufacturers (31 explanted and one demo) were evaluated; all devices with a sufficient battery charge underwent multiple radiations with a 6-MV photon beam reaching a cumulative dose at ICD site of 0.5, 1, 2, 3, 5 and 10 Gy and interrogated after every session. All antitachycardia therapies were left enabled; two ICDs were connected to a rhythm simulator (one simulating a complete atrioventricular block without ventricular activity) and visually monitored by external ECG and the ICD programmer during radiation. Thirteen ICDs were excluded before radiation because of battery depletion; after radiation up to the cumulative dose at the cardiac implantable electronic device site of 10 Gy, in the remaining 19 devices, programmation and battery charge remained unchanged and no switch to safety mode was observed; oversensing, pacing inhibition or inappropriate antitachycardia therapy were neither recorded nor visually observed during radiation. With a low-energy accelerator, neither malfunctions nor electromagnetic interferences were detected radiating the ICDs at doses usually reaching the ICD pocket during radiotherapy sessions. In this context, magnet application to avoid oversensing and inappropriate therapy seems, therefore, useless.

  8. Gallium-containing hydroxyapatite for potential use in orthopedics

    International Nuclear Information System (INIS)

    Melnikov, P.; Teixeira, A.R.; Malzac, A.; Coelho, M. de B.

    2009-01-01

    A novel material that may be recommended for grafts and implants stimulating bone growth has been obtained by introducing gallium ions (up to 11.0 mass%) into crystalline lattice of hydroxyapatite. The doping was carried out using gallium nitrate and sodium gallate solutions. In both cases, lattice parameters of gallium-doped hydroxyapatite are identical to those of pure synthetic hydroxyapatite. Gallium does not replace calcium as a result of heterovalent substitution and consequently produces no distortions in the framework of hydroxyapatite matrix. It remains strongly fixed in the form of solid solution of intercalation. According to scanning electron microscopy images gallium insertion does not cause any morphological alterations in hydroxyapatite structure and the product developed meets physico-chemical criteria for biomaterial to be employed in orthopedic practice and local handling of traumatic injuries. Its future usage opens the opportunity to enhance osteosynthesis and calcium retention in loco.

  9. Validation of an experimental polyurethane model for biomechanical studies on implant supported prosthesis - tension tests

    Directory of Open Access Journals (Sweden)

    Mariane Miyashiro

    2011-06-01

    Full Text Available OBJECTIVES: The complexity and heterogeneity of human bone, as well as ethical issues, frequently hinder the development of clinical trials. The purpose of this in vitro study was to determine the modulus of elasticity of a polyurethane isotropic experimental model via tension tests, comparing the results to those reported in the literature for mandibular bone, in order to validate the use of such a model in lieu of mandibular bone in biomechanical studies. MATERIAL AND METHODS: Forty-five polyurethane test specimens were divided into 3 groups of 15 specimens each, according to the ratio (A/B of polyurethane reagents (PU-1: 1/0.5, PU-2: 1/1, PU-3: 1/1.5. RESULTS: Tension tests were performed in each experimental group and the modulus of elasticity values found were 192.98 MPa (SD=57.20 for PU-1, 347.90 MPa (SD=109.54 for PU-2 and 304.64 MPa (SD=25.48 for PU-3. CONCLUSION: The concentration of choice for building the experimental model was 1/1.

  10. Healing at implants placed in an alveolar ridge with a sloped configuration: an experimental study in dogs.

    Science.gov (United States)

    Abrahamsson, Ingemar; Welander, Maria; Linder, Elena; Berglundh, Tord

    2014-02-01

    To study healing around implants placed in an alveolar ridge with a sloped lingual-buccal configuration. Six Labrador dogs were used. Buccal bone defects were prepared in the mandible after extraction of premolars. Three months later, two test implants with a sloped marginal design and two control implants were placed in the chronic defect area with a sloped lingual-buccal configuration of each premolar region. The test implants were placed in such a way that the buccal margin of the implant coincided with the buccal bone crest. The lingual margin of the control implants was placed to a similar depth as the lingual margin of the test implants. Abutments were connected to the implants in the right mandibular premolar region and flaps were sutured around the neck of the abutments. In the left side of the mandible, cover screws were placed and the flaps were sutured to cover the implants. Biopsies were obtained 4 months later and prepared for histological examination. It was demonstrated that healing around implants placed in an alveolar ridge with a sloped lingual-buccal configuration resulted in the preservation of a vertical discrepancy between the lingual and buccal marginal bone levels around implants with either a regular cylindrical outline or a modified marginal portion that matched the slope of the alveolar ridge. As the marginal buccal portion of the control implants with a regular design had no bone support, it is suggested that implants with a modified marginal portion may be considered in recipient sites with a sloped lingual-buccal configuration. © 2012 Wiley Periodicals, Inc.

  11. [Orthopedic management of spina bifida].

    Science.gov (United States)

    Biedermann, R

    2014-07-01

    Spina bifida is associated with congenital deformities, such as kyphosis, spinal malformations, teratological hip dislocations, clubfeet, vertical talus and also with acquired deformities due to muscle imbalance and impaired biomechanics. The degree of the acquired deformities and the mobility of the patient depend on the level of the spinal lesion. Neurological symptoms are mostly asymmetric and there is an inconsistent correlation between the anatomical level of the lesion and muscle function. Deficits of sensation are usually one to two levels lower than the motor level. An exact neurological diagnosis should not be made before the second or third year of life and an early prognosis about walking ability should be avoided. The level L3 and therefore function of the quadriceps is a functional milestone after which modified independent ambulation with the use of ankle foot orthoses (AFO) and crutches is possible. The basic principle is to support verticalization and gait even when loss of ambulation is later expected. It is also important to support and maintain sitting ability for high lesions, if necessary with correction of the spinal deformity. Findings in gait analysis have shifted the focus of treatment from radiological criteria to functional improvement, thus maintenance of the flexibility of the hip is the main goal of hip surgery. Reduction of the hip often leads to stiffness and has a high redislocation rate. Clubfoot deformities should be treated early and foot arthrodesis and stiffness have to be avoided. Another focus is the prevention of joint contracture by early prophylactic treatment. The purpose of management is to maximize the functional potential of the child. Subjective well-being, absence of pain, mobility and socialization are the main goals. This does not necessarily imply ambulation; nevertheless, verticalization and associated orthotic management is one major objective of the orthopedic management of spina bifida.

  12. Novel Development of Biocompatible Coatings for Bone Implants

    Directory of Open Access Journals (Sweden)

    Nicholas Yue Hou

    2015-10-01

    Full Text Available Prolonged life expectancy also results in an increased need for high-performance orthopedic implants. It has been shown that a compromised tissue-implant interface could lead to adverse immune-responses and even the dislodging of the implant. To overcome these obstacles, our research team has been seeking ways to decrease the risk of faulty tissue-implant interfaces by improving the biocompatibility and the osteo-inductivity of conventional orthopedic implants using ultrafine particle coatings. These particles were enriched with various bioactive additives prior to coating, and the coated biomaterial surfaces exhibited significantly increased biocompatibility and osteoinductivity. Physical assessments firstly confirmed the proper incorporation of the bioactive additives after examining their surface chemical composition. Then, in vitro assays demonstrated the biocompatibility and osteo-inductivity of the coated surfaces by studying the morphology of attached cells and their mineralization abilities. In addition, by quantifying the responses, activities and gene expressions, cellular evaluations confirmed the positive effects of these polymer based bioactive coatings. Consequently, the bioactive ultrafine polymer particles demonstrated their ability in improving the biocompatibility and osteo-inductivity of conventional orthopedic implants. As a result, our research team hope to apply this technology to the field of orthopedic implants by making them more effective medical devices through decreasing the risk of implant-induced immune responses and the loosening of the implant.

  13. Morphological Changes in Blood Cells After Implantation of Titanium and Plastic Clips in the Neurocranium - Experimental Study on Dogs.

    Science.gov (United States)

    Katica, Muhamed; Celebicic, Mirza; Gradascevic, Nedzad; Obhodzas, Muamer; Suljić, Enra; Ocuz, Muhamed; Delibegovic, Samir

    2017-04-01

    Various studies confirm the biocompatibility and efficacy of clips for certain target tissues, but without any comparative analysis of hematological parameters. Therefore, we conducted a study to assess the possible association of the implantation of titanium and plastic clips in the neurocranium with possible morphological changes in the blood cells of experimental animals. As a control, the peripheral blood smears were taken before surgery from 12 adult dogs that were divided into two experimental groups. After placing titanium and plastic clips in the neurocranium, the peripheral blood of the first group was analyzed on the seventh postoperative day, while the peripheral blood of the second group was analyzed on the sixtieth day. By microscopy of the blood smears, the following parameters were analyzed: the presence of poikilocytosis of the red blood cells, degenerative changes in the leukocytes and leukogram. There were no statistically significant differences between the mean values of the groups. Monocytosis was detected (first group 22.83 % and second 16.30 %), as well as neutropenia (46.80 %, in the second group). Degenerative changes to neutrophils and the occurrence of atypical lymphocytes were observed in the second experimental group (60 th postoperative day). A mild adverse effect from the biomaterials present in the neurocranium of dogs was detected, affecting the majority of leukocytic cells. A chronic recurrent inflammatory process was caused by the presence of the plastic and titanium clips in the brain tissue. No adverse effect of biomaterials on erythrocytes in the neurocranium was detected in the dogs studied. Further studies are necessary to explain the occurrence of degenerative changes in the neutrophils and lymphocytes.

  14. Implants for orthodontic anchorage

    Science.gov (United States)

    Zheng, Xiaowen; Sun, Yannan; Zhang, Yimei; Cai, Ting; Sun, Feng; Lin, Jiuxiang

    2018-01-01

    Abstract Implantanchorage continues to receive much attention as an important orthodontic anchorage. Since the development of orthodontic implants, the scope of applications has continued to increase. Although multiple reviews detailing implants have been published, no comprehensive evaluations have been performed. Thus, the purpose of this study was to comprehensively evaluate the effects of implants based on data published in review articles. An electronic search of the Cochrane Library, Medline, Embase, Ebsco and Sicencedirect for reviews with “orthodontic” and “systematic review or meta analysis” in the title, abstract, keywords, or full text was performed. A subsequent manual search was then performed to identify reviews concerning orthodontic implants. A manual search of the orthodontic journals American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), European Journal of Orthodontics (EJO), and Angle Othodontist was also performed. Such systematic reviews that evaluated the efficacy and safety of orthodontic implants were used to indicate success rates and molar movements. A total of 23 reviews were included in the analysis. The quality of each review was assessed using a measurement tool for Assessment of Multiple Systematic Reviews (AMSTAR), and the review chosen to summarize outcomes had a quality score of >6. Most reviews were less than moderate quality. Success rates of implants ranged in a broad scope, and movement of the maxillary first molar was superior with implants compared with traditional anchorage. PMID:29595673

  15. Guided tissue regeneration ensures osseointegration of dental implants placed into extraction sockets. An experimental study in monkeys

    DEFF Research Database (Denmark)

    Warrer, L; Gotfredsen, K; Hjørting-Hansen, E

    1991-01-01

    on the buccal and palatal aspects of the maxillary molars in both sides of the jaw. The second molars were then extracted and self tapping titanium implants of the screw type (Astra Dental Implants) were inserted into the sockets of the largest roots. In the coronal portion of the sockets, a void was always...... present between the implant and the socket walls. In one side of the jaw, a membrane (Gore-Tex Augmentation Material) was adjusted to cover the implant. The implant in the other side of the jaw served as control and was only covered by the tissue flaps. Microscopic analysis after 3 months of healing...... technique can secure complete osseointegration of implants inserted immediately into extraction sockets....

  16. Chronic behavior evaluation of a micro-machined neural implant with optimized design based on an experimentally derived model.

    Science.gov (United States)

    Andrei, Alexandru; Welkenhuysen, Marleen; Ameye, Lieveke; Nuttin, Bart; Eberle, Wolfgang

    2011-01-01

    Understanding the mechanical interactions between implants and the surrounding tissue is known to have an important role for improving the bio-compatibility of such devices. Using a recently developed model, a particular micro-machined neural implant design aiming the reduction of insertion forces dependence on the insertion speed was optimized. Implantations with 10 and 100 μm/s insertion speeds showed excellent agreement with the predicted behavior. Lesion size, gliosis (GFAP), inflammation (ED1) and neuronal cells density (NeuN) was evaluated after 6 week of chronic implantation showing no insertion speed dependence.

  17. Artificial intelligence for analyzing orthopedic trauma radiographs.

    Science.gov (United States)

    Olczak, Jakub; Fahlberg, Niklas; Maki, Atsuto; Razavian, Ali Sharif; Jilert, Anthony; Stark, André; Sköldenberg, Olof; Gordon, Max

    2017-12-01

    Background and purpose - Recent advances in artificial intelligence (deep learning) have shown remarkable performance in classifying non-medical images, and the technology is believed to be the next technological revolution. So far it has never been applied in an orthopedic setting, and in this study we sought to determine the feasibility of using deep learning for skeletal radiographs. Methods - We extracted 256,000 wrist, hand, and ankle radiographs from Danderyd's Hospital and identified 4 classes: fracture, laterality, body part, and exam view. We then selected 5 openly available deep learning networks that were adapted for these images. The most accurate network was benchmarked against a gold standard for fractures. We furthermore compared the network's performance with 2 senior orthopedic surgeons who reviewed images at the same resolution as the network. Results - All networks exhibited an accuracy of at least 90% when identifying laterality, body part, and exam view. The final accuracy for fractures was estimated at 83% for the best performing network. The network performed similarly to senior orthopedic surgeons when presented with images at the same resolution as the network. The 2 reviewer Cohen's kappa under these conditions was 0.76. Interpretation - This study supports the use for orthopedic radiographs of artificial intelligence, which can perform at a human level. While current implementation lacks important features that surgeons require, e.g. risk of dislocation, classifications, measurements, and combining multiple exam views, these problems have technical solutions that are waiting to be implemented for orthopedics.

  18. The influence of external ultrasound on the histologic architecture of the organic capsule around smooth silicone implants: experimental study in rats.

    Science.gov (United States)

    Mendes, F H; Viterbo, F; DeLucca, L

    2008-05-01

    Capsular contracture is the main complication related to breast silicone implants, and its prevention remains a medical challenge. The authors present experimental research examining the effect of external ultrasound on the formation and contracture of peri-implant capsules. In this study, 42 male Wistar rats had a 2-mm smooth surface implant placed in a dorsal submuscular pocket. They then were separated into "ultrasound" and "control" groups that received repeated external applications either with or without the ultrasound power on. Ultrasound applications were given three times a week for a period of 90 days. After that, both groups were housed under the same conditions with no application scheduled. Five animals of each group, killed at 30, 60, 90, and 180 days, had their implants removed along with the capsule, which received a special histologic preparation via annular sectioning that provided wide circumferential observation of the capsular tissue. Sections were stained with hematoxylin/eosin stain, Masson's trichrome stain, and Pricrosirius Red stain for regular microscopic evaluation under normal and polarized light. Histologic data showed that capsules from the ultrasound and control groups had statistically significant differences. Ultrasound application developed a capsular architecture similar to that shown within textured silicone implants, and its effect had an early definition with subsequent stabilization. The authors conclude that early and repeated external ultrasound application enhances the thickness, cellular count, and vascularity of smooth silicone capsular tissue, whereas it diminishes the pattern of parallel orientation of collagen fibers.

  19. Caval filter implantation under MRI control - experimental in vitro and in vivo investigations

    International Nuclear Information System (INIS)

    Neuerburg, J.; Buecker, A.; Adam, G.; Leenen, M.; Guenther, R.W.; Hurtak, M.S.W.

    1997-01-01

    Purpose: An instrument has been developed for the introduction of caval filters which can be used with MRI; it has been investigated in in vitro and in in vivo experiments. Material and method: The ferromagnetic components of a commercially available instrument for the femoral introduction of the MR-eye TM Tulip IVC filter were changed for similar, non-ferromagnetic parts and the lock and dilator marked with dysprosium oxide rings. The instrument was used in a flow phantom and in animal experiments (two domestic pigs) in order to insert filters under MRI control on a 1.5 T Philips Gyroscan with integrated mobile digital subtraction angiography. Results: Both in vitro and in vivo, the introducer, catheter and caval filter could be identified by MRI and positioned under MRI control. The position of the filter as indicated by MRI corresponded with radiological and macroscopic findings in all cases (5 phantoms, 2 pigs). Conclusion: The early experimental results indicate that percutaneous introduction of caval filters with placement under MRI control is possible. (orig.) [de

  20. Experimental model of biofilm implant-related osteomyelitis to test combination biomaterials using biofilms as initial inocula.

    Science.gov (United States)

    Williams, Dustin L; Haymond, Bryan S; Woodbury, Kassie L; Beck, J Peter; Moore, David E; Epperson, R Tyler; Bloebaum, Roy D

    2012-07-01

    Currently, the majority of animal models that are used to study biofilm-related infections use planktonic bacterial cells as initial inocula to produce positive signals of infection in biomaterials studies. However, the use of planktonic cells has potentially led to inconsistent results in infection outcomes. In this study, well-established biofilms of methicillin-resistant Staphylococcus aureus were grown and used as initial inocula in an animal model of a Type IIIB open fracture. The goal of the work was to establish, for the first time, a repeatable model of biofilm implant-related osteomyelitis, wherein biofilms were used as initial inocula to test combination biomaterials. Results showed that 100% of animals that were treated with biofilms developed osteomyelitis, whereas 0% of animals not treated with biofilm developed infection. The development of this experimental model may lead to an important shift in biofilm and biomaterials research by showing that when biofilms are used as initial inocula, they may provide additional insights into how biofilm-related infections in the clinic develop and how they can be treated with combination biomaterials to eradicate and/or prevent biofilm formation. Copyright © 2012 Wiley Periodicals, Inc.

  1. Boron-implantation-induced crystalline-to-amorphous transition in nickel: An experimental assessment of the generalized Lindemann melting criterion

    International Nuclear Information System (INIS)

    Liu, P.C.; Okamoto, P.R.; Zaluzec, N.J.; Meshii, M.

    1999-01-01

    The generalized Lindemann melting hypothesis has recently been used to develop a unified thermodynamic criterion for melting applicable to both heat-induced melting and disorder-induced crystalline-to-amorphous (c-a) transformation. The hypothesis stipulates that the sum left-angle μ 2 right-angle Total of the static and dynamic root-mean-square (rms) atomic displacements is a constant fraction of the nearest-neighbor distance along the melting curve of a solid. To test this hypothesis, energy-filtered selected area electron-diffraction intensity measurements were used to determine the generalized Lindemann parameter δ=√ (left-angle μ 2 right-angle Total ) /d nn , in which d nn represents the nearest-neighbor distance, as a function of boron concentration during implantation of 50-keV ampersand hthinsp;B + into polycrystalline Ni at 77 K. The onset of amorphization was found to occur close to 10 at.ampersand hthinsp;% boron, which is in good agreement with the value predicted by T o curve calculated using the generalized Lindemann hypothesis. Moreover, the critical value of the generalized Lindemann parameter for amorphization, δ Critical =0.115±0.01, is within experimental error, identical to that for Ni just below its thermodynamic melting temperature of T=1728 ampersand hthinsp;K, hence providing a direct confirmation for the generalized Lindemann melting hypothesis. copyright 1999 The American Physical Society

  2. [Research and analysis to Shui nationality medicine treatment orthopedics & traumatology].

    Science.gov (United States)

    Hu, Jian-Shan; Li, Pu; Yang, Yong; Chen, Xin-Chun; Lin, Li

    2013-05-01

    To investigated Shui nationality folk medicine's awareness to orthopedics & traumatology, the history of orthopedics & traumatology treatment, Shui nationality folk doctors' practicing medicine, heritage, diagnosis and treatment methods and tools, etc, through investigated drug resources category and distribution characteristics of Shui nationality medicine to orthopedics & traumatology treatment, explored and finished Shui nationality medicine orthopedics & traumatology treatment theoretical system. After more than 5 years' exploration and finishing, preliminarily formed the theoretical system framework and medicine application characteristics of Shui nationality medicine treating orthopedics & traumatology. Shui nationality medicine treatment orthopedics & traumatology has distinctive national style, and worthy to further exploration and research.

  3. Surgeons' Perspectives on Premium Implants in Total Joint Arthroplasty.

    Science.gov (United States)

    Wasterlain, Amy S; Bello, Ricardo J; Vigdorchik, Jonathan; Schwarzkopf, Ran; Long, William J

    2017-09-01

    Declining total joint arthroplasty reimbursement and rising implant prices have led many hospitals to restrict access to newer, more expensive total joint arthroplasty implants. The authors sought to understand arthroplasty surgeons' perspectives on implants regarding innovation, product launch, costs, and cost-containment strategies including surgeon gain-sharing and patient cost-sharing. Members of the International Congress for Joint Reconstruction were surveyed regarding attitudes about implant technology and costs. Descriptive and univariate analyses were performed. A total of 126 surgeons responded from all 5 regions of the United States. Although 76.9% believed new products advance technology in orthopedics, most (66.7%) supported informing patients that new implants lack long-term clinical data and restricting new implants to a small number of investigators prior to widespread market launch. The survey revealed that 66.7% would forgo gain-sharing incentives in exchange for more freedom to choose implants. Further, 76.9% believed that patients should be allowed to pay incremental costs for "premium" implants. Surgeons who believed that premium products advance orthopedic technology were more willing to forgo gain-sharing (P=.040). Surgeons with higher surgical volume (P=.007), those who believed implant companies should be allowed to charge more for new technology (Pnew implants with patients. Many surgeons support alternative payment models permitting surgeons and patients to retain implant selection autonomy. Most respondents prioritized patient beneficence and surgeon autonomy above personal financial gain. [Orthopedics. 2017; 40(5):e825-e830.]. Copyright 2017, SLACK Incorporated.

  4. EXPERIMENTAL AND CLINICAL STUDY OF PHENOTYPIC FEATURES OF S. EPIDERMIDIS STRAINS AND THEIR ROLE IN THE EMERGENCE AND DEVELOPMENT OF IMPLANT-ASSOCIATED INFECTION AFTER ORTHOPAEDIC SURGERY

    Directory of Open Access Journals (Sweden)

    S. A. Bozhkova

    2014-01-01

    Full Text Available S. epidermidis is one of the most common cause of implant-associated infections. Infections due to S. epidermidis rarely develops into life-threatening, however, its prevalence and the difficulties in treating constitute a serious financial burden to the health care system. This study is based on the investigation of phenotypic features (ability to biofilm formation and resistance to antibiotics of S. epidermidis strains isolated from patients with deep surgical site infection after implantation of orthopaedic devices, and on the investigation of the dynamics of clinical and morphological changes during the development of implant-associated infection due to S. epidermidis based on in vivo experimental models. Multidrug-resistance was found in 23% MSSE isolates and 97,3% - MRSE. Vancomycin, linezolid and fosfomycin were the most active in relation to these pathogens. About 40% of the tested isolates were strong biofilm-producing strains. 43,2% of MRSE strains and only 21,4% of MSSE isolates demonstrated strong biofilm production. The proposed experimental model shows that intra-operative infection of implant by multidrug-resistant clinical MRSE strain led to the development of osteomyelitis in rats for 4 weeks after surgery, in spite of the revision operation and installation of antimicrobial cement spacer in the area of bone defect. Thus, S. epidermidis is a clinically significant aetiological factor with high risk of development of infections after major orthopaedic surgery.

  5. Evaluation of guided bone generation around implants placed into fresh extraction sockets: an experimental study in dogs

    DEFF Research Database (Denmark)

    Gotfredsen, K; Nimb, L; Buser, D

    1993-01-01

    Immediate placement of implants into fresh extraction sockets would have the principal advantage of decreasing the recommended period of healing. It also would result in a guided placement of the implant, and it could reduce the resorption of the alveolar bone in the extraction area. However, when...... an implant is placed immediately into an extraction socket, it may not engage the walls of the socket near the crest of the alveolar ridge. With the presence of a bone defect around an implant, ingrowth of soft tissue could compromise the achievement of osseointegration in the crestal bone area....... The objective of this study was to evaluate the crestal bone healing response adjacent to implants placed immediately into fresh extraction sockets with and without covering membranes. Eight adult mongrel dogs had the third and fourth mandibular premolars extracted bilaterally. Thirty-two submerged titanium...

  6. A paradigm for the development and evaluation of novel implant topologies for bone fixation: in vivo evaluation.

    Science.gov (United States)

    Long, Jason P; Hollister, Scott J; Goldstein, Steven A

    2012-10-11

    While contemporary prosthetic devices restore some function to individuals who have lost a limb, there are efforts to develop bio-integrated prostheses to improve functionality. A critical step in advancing this technology will be to securely attach the device to remnant bone. To investigate mechanisms for establishing robust implant fixation in bone while undergoing loading, we previously used a topology optimization scheme to develop optimized orthopedic implants and then fabricated selected designs from titanium (Ti)-alloy with selective laser sintering (SLS) technology. In the present study, we examined how implant architecture and mechanical stimulation influence osseointegration within an in vivo environment. To do this, we evaluated three implant designs (two optimized and one non-optimized) using a unique in vivo model that applied cyclic, tension/compression loads to the implants. Eighteen (six per implant design) adult male canines had implants surgically placed in their proximal, tibial metaphyses. Experimental duration was 12 weeks; daily loading (peak load of ±22 N for 1000 cycles) was applied to one of each animal's bilateral implants for the latter six weeks. Following harvest, osseointegration was assessed by non-destructive mechanical testing, micro-computed tomography (microCT) and back-scatter scanning electron microscopy (SEM). Data revealed that implant loading enhanced osseointegration by significantly increasing construct stiffness, peri-implant trabecular morphology, and percentages of interface connectivity and bone ingrowth. While this experiment did not demonstrate a clear advantage associated with the optimized implant designs, osseointegration was found to be significantly influenced by aspects of implant architecture. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Contributing risk factors for orthopedic device related infections in sina hospital, tehran, iran.

    Science.gov (United States)

    Hadadi, A; Zehtab, M J; Babagolzadeh, H; Ashraf, H

    2011-02-01

    In spite of decreasing incidence of orthopedic device-related infections to 1%, nowadays, device-related infection still remains a diagnostic, therapeutic and cost-related problem. The objective of this study is to evaluate the contributing risk factors for orthopedic device-related infections in Sina Hospital, Tehran, Iran. Three hundred and thirty patients who underwent orthopedic device implantation from 2002-2006 were enrolled; among them, 110 patients were complicated with infection. Descriptive and logistic regression analyses were performed to determine the risk factors for device related infections. Patients with infection were older compared to those without infection. The Staphylococcus aureus was the commonest organism. A correlation was observed between wound infection and external fixation, an underlying health condition, and addiction which were independent risk factors for a device related infection. Orthopedic device-related infection puts a great financial burden on patients and hospital resources and could lead to morbidity and mortality in patients. So, appropriate pre and postoperative wound care for dirty wounds, especially when external fixators are used, and in patients with poor conditions or addiction should be done with more caution.

  8. A novel implantation model for evaluation of bone healing response to dental implants: the goat iliac crest.

    NARCIS (Netherlands)

    Schouten, C.; Meijer, G.J.; Beucken, J.J.J.P van den; Spauwen, P.H.M.; Jansen, J.A.

    2010-01-01

    OBJECTIVES: Despite the availability of numerous animal models for testing the biological performance of dental and orthopedic implants, the selection of a suitable model is complex. This paper presents a new model for objective and standardized evaluation of bone responses to implants using the

  9. Hydroxyapatite electrodeposition on anodized titanium nanotubes for orthopedic applications

    Science.gov (United States)

    Parcharoen, Yardnapar; Kajitvichyanukul, Puangrat; Sirivisoot, Sirinrath; Termsuksawad, Preecha

    2014-08-01

    Nanotubes modification for orthopedic implants has shown interesting biological performances (such as improving cell adhesion, cell differentiation, and enhancing osseointegration). The purpose of this study is to investigate effect of titanium dioxide (TiO2) nanotube feature on performance of hydroxyapatite-coated titanium (Ti) bone implants. TiO2 nanotubes were prepared by anodization using ammonium fluoride electrolyte (NH4F) with and without modifiers (PEG400 and Glycerol) at various potential forms, and times. After anodization, the nanotubes were subsequently annealed. TiO2 nanotubes were characterized by scanning electron microscope and X-ray diffractometer. The amorphous to anatase transformation due to annealing was observed. Smooth and highly organized TiO2 nanotubes were found when high viscous electrolyte, NH4F in glycerol, was used. Negative voltage (-4 V) during anodization was confirmed to increase nanotube thickness. Length of the TiO2 nanotubes was significantly increased by times. The TiO2 nanotube was electrodeposited with hydroxyapatite (HA) and its adhesion was estimated by adhesive tape test. The result showed that nanotubes with the tube length of 560 nm showed excellent adhesion. The coated HA were tested for biological test by live/dead cell straining. HA coated on TiO2 nanotubes showed higher cells density, higher live cells, and more spreading of MC3T3-E1 cells than that growing on titanium plate surface.

  10. Integration of implant planning workflows into the PACS infrastructure

    Science.gov (United States)

    Gessat, Michael; Strauß, Gero; Burgert, Oliver

    2008-03-01

    The integration of imaging devices, diagnostic workstations, and image servers into Picture Archiving and Communication Systems (PACS) has had an enormous effect on the efficiency of radiology workflows. The standardization of the information exchange between the devices with the DICOM standard has been an essential precondition for that development. For surgical procedures, no such infrastructure exists. With the increasingly important role computerized planning and assistance systems play in the surgical domain, an infrastructure that unifies the communication between devices becomes necessary. In recent publications, the need for a modularized system design has been established. A reference architecture for a Therapy Imaging and Model Management System (TIMMS) has been proposed. It was accepted by the DICOM Working Group 6 as the reference architecture for DICOM developments for surgery. In this paper we propose the inclusion of implant planning systems into the PACS infrastructure. We propose a generic information model for the patient specific selection and positioning of implants from a repository according to patient image data. The information models are based on clinical workflows from ENT, cardiac, and orthopedic surgery as well as technical requirements derived from different use cases and systems. We show an exemplary implementation of the model for application in ENT surgery: the selection and positioning of an ossicular implant in the middle ear. An implant repository is stored in the PACS. It makes use of an experimental implementation of the Surface Mesh Module that is currently being developed as extension to the DICOM standard.

  11. Awareness campaign. Orthopedic Hospital of Oklahoma launches awareness campaign.

    Science.gov (United States)

    2007-01-01

    The Orthopedic Hospital of Oklahoma is a 25-bed inpatient and outpatient center with one focus: Orthopedics. To acquaint people with its services and build brand awareness to drive market share, the hospital launched a print campaign featuring actual patients.

  12. Zirconium, calcium, and strontium contents in magnesium based biodegradable alloys modulate the efficiency of implant-induced osseointegration

    Directory of Open Access Journals (Sweden)

    Mushahary D

    2013-08-01

    Full Text Available Dolly Mushahary,1,2 Ragamouni Sravanthi,2 Yuncang Li,2 Mahesh J Kumar,1 Nemani Harishankar,4 Peter D Hodgson,1 Cuie Wen,3 Gopal Pande2 1Institute for Frontier Materials, Deakin University, Geelong, Australia; 2CSIR- Centre for Cellular and Molecular Biology, Hyderabad, India; 3Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Hawthorn, Australia; 4National Institute of Nutrition (ICMR, Tarnaka, Hyderabad, India Abstract: Development of new biodegradable implants and devices is necessary to meet the increasing needs of regenerative orthopedic procedures. An important consideration while formulating new implant materials is that they should physicochemically and biologically mimic bone-like properties. In earlier studies, we have developed and characterized magnesium based biodegradable alloys, in particular magnesium-zirconium (Mg-Zr alloys. Here we have reported the biological properties of four Mg-Zr alloys containing different quantities of strontium or calcium. The alloys were implanted in small cavities made in femur bones of New Zealand White rabbits, and the quantitative and qualitative assessments of newly induced bone tissue were carried out. A total of 30 experimental animals, three for each implant type, were studied, and bone induction was assessed by histological, immunohistochemical and radiological methods; cavities in the femurs with no implants and observed for the same period of time were kept as controls. Our results showed that Mg-Zr alloys containing appropriate quantities of strontium were more efficient in inducing good quality mineralized bone than other alloys. Our results have been discussed in the context of physicochemical and biological properties of the alloys, and they could be very useful in determining the nature of future generations of biodegradable orthopedic implants. Keywords: osteoblasts, bone mineralization, corrosion, osseointegration, surface energy, peri-implant

  13. Immediate implant placement using a biodegradable barrier, polyhydroxybutyrate-hydroxyvalerate reinforced with polyglactin 910. An experimental study in dogs

    DEFF Research Database (Denmark)

    Gotfredsen, K; Nimb, L; Hjørting-Hansen, E

    1994-01-01

    The purpose of this study was to evaluate the use of a biodegradable membrane of polyhydroxybutyrate-hydroxyvalerate copolymer reinforced with polyglactin 910 fibers, as an occlusive barrier over implants placed into fresh extraction sockets. Ten dogs had the 3rd and 4th mandibular premolars...... extracted bilaterally. Each dog had 4 Astra Dental Implants placed directly into the fresh extraction sockets. The top of the fixtures was placed at the same level as the top of the buccal cortical bone. The two implants in the right side were covered with the hydrolyzable polyester material...

  14. 915 MHz microwave ablation with implanted internal cooled-shaft antenna: Initial experimental study in in vivo porcine livers

    International Nuclear Information System (INIS)

    Cheng Zhigang; Xiao Qiujin; Wang Yang; Sun Yuanyuan; Lu Tong; Liang Ping

    2011-01-01

    Purpose: To explore a preferred power output for further clinical application based on the ablated lesions induced by the four power outputs of 915 MHz microwave in experimental study of in vivo porcine livers. Materials and methods: A KY2000-915 microwave ablation system with an implanted 915 MHz internal cooled-shaft antenna was used in this study. A total of 24 ablations were performed in eight in vivo porcine livers. The energy was applied for 10 min at microwave output powers of 50 W, 60 W, 70 W, and 80 W. Long-axis and short-axis diameters of the coagulation zone were measured on all gross specimens. Results: The shapes of the 915 MHz microwave ablation lesions were elliptical commonly. As the power increased, the long-axis and short-axis diameters of the coagulation zone had a tendency to rise. But the long-axis diameter of the ablated lesion at 50 W was not significantly smaller than that of the ablated lesion at 60 W (P > 0.05) and there were no statistical differences in short-axis diameters of the ablated lesion among the three power outputs of 60 W, 70 W and 80 W (P > 0.05). After 10 min irradiation of 60 W, the long-axis and short-axis diameters of the coagulation zone were 5.02 ± 0.60 cm and 3.65 ± 0.46 cm, respectively. Conclusions: For decreasing the undesired damages of liver tissues along the shaft and the number of antenna in further clinically percutaneous microwave ablation treatment, the power of 60 W may be a preferred setting among the four power outputs used in present study.

  15. Prosthesis infections after orthopedic joint replacement

    DEFF Research Database (Denmark)

    Song, Zhijun; Borgwardt, Lotte; Høiby, Niels

    2013-01-01

    Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore...

  16. Molecular imaging promotes progress in orthopedic research.

    Science.gov (United States)

    Mayer-Kuckuk, Philipp; Boskey, Adele L

    2006-11-01

    Modern orthopedic research is directed towards the understanding of molecular mechanisms that determine development, maintenance and health of musculoskeletal tissues. In recent years, many genetic and proteomic discoveries have been made which necessitate investigation under physiological conditions in intact, living tissues. Molecular imaging can meet this demand and is, in fact, the only strategy currently available for noninvasive, quantitative, real-time biology studies in living subjects. In this review, techniques of molecular imaging are summarized, and applications to bone and joint biology are presented. The imaging modality most frequently used in the past was optical imaging, particularly bioluminescence and near-infrared fluorescence imaging. Alternate technologies including nuclear and magnetic resonance imaging were also employed. Orthopedic researchers have applied molecular imaging to murine models including transgenic mice to monitor gene expression, protein degradation, cell migration and cell death. Within the bone compartment, osteoblasts and their stem cells have been investigated, and the organic and mineral bone phases have been assessed. These studies addressed malignancy and injury as well as repair, including fracture healing and cell/gene therapy for skeletal defects. In the joints, molecular imaging has focused on the inflammatory and tissue destructive processes that cause arthritis. As described in this review, the feasibility of applying molecular imaging to numerous areas of orthopedic research has been demonstrated and will likely result in an increase in research dedicated to this powerful strategy. Molecular imaging holds great promise in the future for preclinical orthopedic research as well as next-generation clinical musculoskeletal diagnostics.

  17. Emotional intelligence in orthopedic surgery residents.

    Science.gov (United States)

    Chan, Kevin; Petrisor, Brad; Bhandari, Mohit

    2014-04-01

    Emotional intelligence (EI) is the ability to understand and manage emotions in oneself and others. It was originally popularized in the business literature as a key attribute for success that was distinct from cognitive intelligence. Increasing focus is being placed on EI in medicine to improve clinical and academic performance. Despite the proposed benefits, to our knowledge, there have been no previous studies on the role of EI in orthopedic surgery. We evaluated baseline data on EI in a cohort of orthopedic surgery residents. We asked all orthopedic surgery residents at a single institution to complete an electronic version of the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). We used completed questionnaires to calculate total EI scores and 4 branch scores. Data were analyzed according to a priori cutoff values to determine the proportion of residents who were considered competent on the test. Data were also analyzed for possible associations with age, sex, race and level of training. Thirty-nine residents (100%) completed the MSCEIT. The mean total EI score was 86 (maximum score 145). Only 4 (10%) respondents demonstrated competence in EI. Junior residents (p = 0.026), Caucasian residents (p = 0.009) and those younger than 30 years (p = 0.008) had significantly higher EI scores. Our findings suggest that orthopedic residents score low on EI based on the MSCEIT. Optimizing resident competency in noncognitive skills may be enhanced by dedicated EI education, training and testing.

  18. Neonatal maxillary orthopedics: past to present

    NARCIS (Netherlands)

    Kuijpers-Jagtman, A.M.; Prahl, C.; Berkowitz, S.

    2013-01-01

    Neonatal maxillary orthopedics was introduced in the treatment protocol for cleft lip and palate in the 1950s of the last century. A wide range of appliances has been designed with pin-retained active appliances at one end of the spectrum and passive appliances at the other. Although neonatal

  19. Morphological and chemical evaluation of bone with apatite-coated Al2O3 implants as scaffolds for bone repair

    Directory of Open Access Journals (Sweden)

    A. L. M. Maia F.

    2013-12-01

    Full Text Available The clinical challenge in the reconstruction of bone defects has stimulated several studies in search of alternatives to repair these defects. The ceramics are considered as synthetic scaffolds and are used in dentistry and orthopedics. This study aimed to evaluate by micro energy-dispersive X-ray fluorescence spectrometry (µ-EDXRF and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS, the influence of uncoated and apatite-coated Al2O3 implants on bone regeneration. Twelve samples of Al2O3 implants were prepared and half of this samples (n = 6 were apatite-coated by the modified biomimetic method and then the ceramic material were implanted in the tibia of rabbits. Three experimental groups were tested: Group C - control, surgery procedure without ceramic implant, Group Ce - uncoated Al2O3 implants (n = 6 and Group CeHA - apatite-coated Al2O3 implants (n = 6. The deposition of bone tissue was determined by measuring the weight content of Ca and P through surface mapping of bone-implant interface by µ-EDXRF and through point analysis by EDS. It was observed after thirty days of treatment a greater deposition of Ca and P in the group treated with CeHA (p <0.001 compared to group C. The results suggest that ceramic coated with hydroxyapatite (CeHA can be an auxiliary to bone deposition in tibia defect model in rabbits.

  20. Influence of titanium implant surface characteristics on bone regeneration in dehiscence-type defects: an experimental study in dogs.

    Science.gov (United States)

    Schwarz, Frank; Sager, Martin; Kadelka, Ines; Ferrari, Daniel; Becker, Jürgen

    2010-05-01

    The aim of the present study was to compare bone regeneration in dehiscence-type defects at titanium implants with chemically modified sandblasted/acid-etched (modSLA) or dual acid-etched surfaces with a calcium phosphate nanometre particle modification (DCD/CaP). Buccal dehiscence-type defects were surgically created following implant site preparation in both the upper and the lower jaws of 12 fox hounds. Both types of implants were randomly allocated in a split-mouth design and left to heal in a submerged position for 2 and 8 weeks. Dissected blocks were processed for histomorphometrical analysis [e.g. new bone height (NBH), percentage of bone-to-implant contact (BIC), area of new bone fill (BF), and area of mineralized tissue (MT) within BF]. At 2 and 8 weeks, both groups revealed comparable mean BF (2.3+/-0.6 to 2.5+/-0.6 mm(2)versus 2.0+/-0.6 to 1.4+/-0.5 mm(2)) and MT (31.1+/-14.3-83.2+/-8.2%versus 38.9+/-15.9-84.4+/-6.3%) values. However, modSLA implants revealed significantly higher mean NBH (2.4+/-0.8 to 3.6+/-0.3 mm versus 0.9+/-0.8 to 1.8+/-1.4 mm) and BIC (53.3+/-11.3-79.5+/-6.6%versus 19.3+/-16.4-47.2+/-30.7%) values than DCD/CaP implants. ModSLA implants may have a higher potential to support osseointegration in dehiscence-type defects than DCD/CaP implants.

  1. Surface modification of implants in long bone.

    Science.gov (United States)

    Förster, Yvonne; Rentsch, Claudia; Schneiders, Wolfgang; Bernhardt, Ricardo; Simon, Jan C; Worch, Hartmut; Rammelt, Stefan

    2012-01-01

    Coatings of orthopedic implants are investigated to improve the osteoinductive and osteoconductive properties of the implant surfaces and thus to enhance periimplant bone formation. By applying coatings that mimic the extracellular matrix a favorable environment for osteoblasts, osteoclasts and their progenitor cells is provided to promote early and strong fixation of implants. It is known that the early bone ongrowth increases primary implant fixation and reduces the risk of implant failure. This review presents an overview of coating titanium and hydroxyapatite implants with components of the extracellular matrix like collagen type I, chondroitin sulfate and RGD peptide in different small and large animal models. The influence of these components on cells, the inflammation process, new bone formation and bone/implant contact is summarized.

  2. Evaluation of a New Dental Implant Cervical Design in Comparison with a Conventional Design in an Experimental American Foxhound Model.

    Science.gov (United States)

    Pérez-Albacete Martínez, Maria Ángeles; Pérez-Albacete Martínez, Carlos; Maté Sánchez De Val, José Eduardo; Ramos Oltra, María Luisa; Fernández Domínguez, Manuel; Calvo Guirado, Jose Luis

    2018-03-21

    The aim of this study was to evaluate osseointegration and crestal bone height in implants with a triangular cervical design in comparison with a standard rounded cervical design. The control group consisted of 24 implants with a standard cervical design, and the test group of 24 implants with a triangular cervical design. The implants were inserted in healed bone in six American Foxhounds. Crestal bone height and tissue thickness in the cervical portion were measured after 12 weeks healing. Data analysis found mean crestal bone loss of: 0.31 ± 0.24 mm on the buccal side, 0.35 ± 0.14 mm on the lingual in the test group, and 0.71 ± 0.28 mm buccal loss, and 0.42 ± 0.30 mm lingual in the control group; with statistically significant differences on the buccal aspect ( p = 0.0019). Mean tissue thickness in the test group was 1.98 ± 0.17 mm on the buccal aspect, and 2.43 ± 0.93 mm in the lingual; in the control group it was 2.48 ± 0.61 mm buccal thickness, and 2.88 ± 0.14 mm lingual, with significant differences on both aspects ( p = 0.0043; p = 0.0029). The results suggest that greater thickness of peri-implant tissue can be expected when the triangular cervical implant design is used rather than the standard cervical design.

  3. Experimental and numerical optical characterization of plasmonic copper nanoparticles embedded in ZnO fabricated by ion implantation and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Le, Khai Q. [Faculty of Science and Technology, Hoa Sen University, Ho Chi Minh City (Viet Nam); Department of Physics, Faculty of Science, Jazan University, P.O. Box 114, 45142 Jazan (Saudi Arabia); Nguyen, Hieu P.T. [Department of Electrical and Computer Engineering, New Jersey Institute of Technology, NJ 07102 (United States); Ngo, Quang Minh [Institute of Material Sciences, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi (Viet Nam); Canimoglu, Adil [Nigde University, Faculty of Arts and Sciences, Physics Department, Nigde (Turkey); Can, Nurdogan, E-mail: cannurdogan@yahoo.com [Celal Bayar University, Faculty of Arts and Sciences, Department of Physics, Muradiye, Manisa (Turkey); Department of Physics, Faculty of Science, Jazan University, P.O. Box 114, 45142 Jazan (Saudi Arabia)

    2016-06-05

    Here we describe the successfully fabrication of metal nanoparticle crystals by implanting copper (Cu) ions into single zinc oxide (ZnO) crystals with ion energy of 400 keV at ion doses of 1 × 10{sup 16} to 1 × 10{sup 17} ions/cm{sup 2}. After implantation and post-annealing treatment, the Cu implanted ZnO produces a broad range of luminescence emissions, ranging from green to yellow. A green luminescence peak at 550 nm could be ascribed to the isolated Cu ions. The changes in luminescence emission bands between the initial implant and annealed suggest that the implants give rise to clustering Cu nanoparticles in the host matrix but that the annealing process dissociates these. Numerical modelling of the Cu nanoparticles was employed to simulate their optical properties including the extinction cross section, electron energy loss spectroscopy and cathodoluminescence. We demonstrate that the clustering of nanoparticles generates Fano resonances corresponding to the generation of multiple resonances, while the isolation of nanoparticles results in intensity amplification. - Highlights: • We present the fabrication of metal nanoparticle crystals by implanting Cu into ZnO. • The luminescence properties were studied at different annealing temperature. • Numerical modelling of the Cu nanoparticles was employed. • We demonstrate that the clustering of nanoparticles generates Fano resonances.

  4. Bone modelling at fresh extraction sockets: immediate implant placement versus spontaneous healing: an experimental study in the beagle dog.

    Science.gov (United States)

    Vignoletti, Fabio; Discepoli, Nicola; Müller, Anna; de Sanctis, Massimo; Muñoz, Fernando; Sanz, Mariano

    2012-01-01

    The purpose of this investigation is to describe histologically the undisturbed healing of fresh extraction sockets when compared to immediate implant placement. In eight beagle dogs, after extraction of the 3P3 and 4P4, implants were inserted into the distal sockets of the premolars, while the mesial sockets were left to heal spontaneously. Each animal provided four socket sites (control) and four implant sites (test). After 6 weeks, animals were sacrificed and tissue blocks were dissected, prepared for ground sectioning. The relative vertical buccal bone resorption in relation to the lingual bone was similar in both test and control groups. At immediate implant sites, however, the absolute buccal bone loss observed was 2.32 (SD 0.36) mm, what may indicate that while an apical shift of both the buccal and lingual bone crest occurred at the implant sites, this may not happen in naturally healing sockets. The results from this investigation showed that after tooth extraction the buccal socket wall underwent bone resorption at both test and control sites. This resorption appeared to be more pronounced at the implant sites, although the limitations of the histological evaluation method utilized preclude a definite conclusion. © 2011 John Wiley & Sons A/S.

  5. Evaluation of a New Dental Implant Cervical Design in Comparison with a Conventional Design in an Experimental American Foxhound Model

    Directory of Open Access Journals (Sweden)

    Maria Ángeles Pérez-Albacete Martínez

    2018-03-01

    Full Text Available The aim of this study was to evaluate osseointegration and crestal bone height in implants with a triangular cervical design in comparison with a standard rounded cervical design. The control group consisted of 24 implants with a standard cervical design, and the test group of 24 implants with a triangular cervical design. The implants were inserted in healed bone in six American Foxhounds. Crestal bone height and tissue thickness in the cervical portion were measured after 12 weeks healing. Data analysis found mean crestal bone loss of: 0.31 ± 0.24 mm on the buccal side, 0.35 ± 0.14 mm on the lingual in the test group, and 0.71 ± 0.28 mm buccal loss, and 0.42 ± 0.30 mm lingual in the control group; with statistically significant differences on the buccal aspect (p = 0.0019. Mean tissue thickness in the test group was 1.98 ± 0.17 mm on the buccal aspect, and 2.43 ± 0.93 mm in the lingual; in the control group it was 2.48 ± 0.61 mm buccal thickness, and 2.88 ± 0.14 mm lingual, with significant differences on both aspects (p = 0.0043; p = 0.0029. The results suggest that greater thickness of peri-implant tissue can be expected when the triangular cervical implant design is used rather than the standard cervical design.

  6. Stress Distribution in Single Dental Implant System: Three-Dimensional Finite Element Analysis Based on an In Vitro Experimental Model.

    Science.gov (United States)

    Rezende, Carlos Eduardo Edwards; Chase-Diaz, Melody; Costa, Max Doria; Albarracin, Max Laurent; Paschoeto, Gabriela; Sousa, Edson Antonio Capello; Rubo, José Henrique; Borges, Ana Flávia Sanches

    2015-10-01

    This study aimed to analyze the stress distribution in single implant system and to evaluate the compatibility of an in vitro model with finite element (FE) model. The in vitro model consisted of Brånemark implant; multiunit set abutment of 5 mm height; metal-ceramic screw-retained crown, and polyurethane simulating the bone. Deformations were recorded in the peri-implant region in the mesial and distal aspects, after an axial 300 N load application at the center of the occlusal aspect of the crown, using strain gauges. This in vitro model was scanned with micro CT to design a three-dimensional FE model and the strains in the peri-implant bone region were registered to check the compatibility between both models. The FE model was used to evaluate stress distribution in different parts of the system. The values obtained from the in vitro model (20-587 με) and the finite element analysis (81-588 με) showed agreement among them. The highest stresses because of axial and oblique load, respectively were 5.83 and 40 MPa for the cortical bone, 55 and 1200 MPa for the implant, and 80 and 470 MPa for the abutment screw. The FE method proved to be effective for evaluating the deformation around single implant. Oblique loads lead to higher stress concentrations.

  7. Preparation Methods for Improving PEEK’s Bioactivity for Orthopedic and Dental Application: A Review

    Directory of Open Access Journals (Sweden)

    Davood Almasi

    2016-01-01

    Full Text Available There is an increased interest in the use of polyether ether ketone (PEEK for orthopedic and dental implant applications due to its elastic modulus close to that of bone, biocompatibility, and its radiolucent properties. However, PEEK is still categorized as bioinert due to its low integration with surrounding tissues. Many studies have reported on methods to increase the bioactivity of PEEK, but there is still one-preparation method for preparing bioactive PEEK implant where the produced implant with desirable mechanical and bioactivity properties is required. The aim of this review is to present the progress of the preparation methods for improvement of the bioactivity of PEEK and to discuss the strengths and weaknesses of the existing methods.

  8. A New Experimental Design for Bacterial Microleakage Investigation at the Implant-Abutment Interface: An In Vitro Study.

    Science.gov (United States)

    Zipprich, Holger; Miatke, Sven; Hmaidouch, Rim; Lauer, Hans-Christoph

    2016-01-01

    This study aimed to test bacterial microleakage at the implant-abutment interface (IAI) before and after dynamic loading using a new chewing simulation. Fourteen implant systems (n = 5 samples of each) were divided into two groups: (1) systems with conical implant-abutment connections (IACs), and (2) systems with flat IACs. For collecting samples without abutment disconnection, channels (Ø = 0.3 mm) were drilled into implants perpendicularly to their axes, and stainless-steel cannulas were adhesively glued inside these channels to allow a sterilized rinsing solution to enter the implant interior and to exit with potential contaminants for testing. Implants were embedded in epoxy resin matrices, which were supported by titanium cylinders with lateral openings for inward and outward cannulas. Abutments were tightened and then provided with vertically adjustable, threaded titanium balls, which were cemented using composite cement. Specimens were immersed in a bacterial liquid and after a contact time of 15 minutes, the implant interior was rinsed prior to chewing simulation (0 N ≘ static seal testing). Specimens were exposed to a Frankfurt chewing simulator. Two hundred twenty force cycles per power level (110 in ± X-axis) were applied to simulate a daily masticatory load of 660 chewing cycles (equivalent to 1,200,000 cycles/5 years). The applied load was gradually increased from 0 N to a maximum load of 200 N in 25-N increments. The implant interior was rinsed to obtain samples before each new power level. All samples were tested using fluorescence microscopy; invading microorganisms could be counted and evaluated. No bacterial contamination was detected under static loading conditions in both groups. After loading, bacterial contamination was detected in one sample from one specimen in group 1 and in two samples from two specimens in group 2. Controlled dynamic loading applied in this study simulated a clinical situation and enabled time-dependent analysis

  9. A long-term in vivo investigation on the effects of xenogenous based, electrospun, collagen implants on the healing of experimentally-induced large tendon defects.

    Science.gov (United States)

    Oryan, A; Moshiri, A; Parizi Meimandi, A; Silver, I A

    2013-09-01

    This study was designed to investigate the effect of novel 3-dimensional (3-D) collagen implants on the healing of large, experimentally-induced, tendon-defects in rabbits. Forty mature male white New Zealand rabbits were divided randomly into treated and control groups. Two cm of the left Achilles tendon was excised and the gap was spanned by Kessler suture. In the treated group, a novel 3-D collagen implant was inserted between the cut ends of the tendon. No implant was used in the control group. During the course of the experiment the bioelectrical characteristics of the healing and normal tendons of both groups were investigated weekly. At 120 days post injury (DPI), the tendons were dissected and inspected for gross pathology, examined by transmission and scanning electron microscopy, and their biomechanical properties, percentage dry matter and hydroxyproline concentration assessed. The collagen implant significantly improved the bioelectrical characteristics, gross appearance and tissue alignment of the healed, treated tendons, compared to the healed, control scars. It also significantly increased fibrillogenesis, diameter and density of the collagen fibrils, dry matter content, hydroxyproline concentration, maximum load, stiffness, stress and modulus of elasticity of the treated tendons, as compared to the control tendons. Treatment also significantly decreased peri-tendinous adhesions, and improved the hierarchical organization of the tendon from the collagen fibril to fibre-bundle level. 3-D xenogeneic-based collagen implants induced newly regenerated tissue that was ultrastructurally and biomechanically superior to tissue that was regenerated by natural unassisted healing. This type of bioimplant was biocompatible, biodegradable and appeared suitable for clinical use.

  10. Refining experimental dental implant testing in the Göttingen Minipig using 3D computed tomography-A morphometric study of the mandibular canal.

    Directory of Open Access Journals (Sweden)

    Giuliano M Corte

    Full Text Available This study reports morphometric and age-related data of the mandibular canal and the alveolar ridge of the Göttingen Minipig to avoid complications during in vivo testing of endosseus dental implants and to compare these data with the human anatomy. Using 3D computed tomography, six parameters of the mandibular canal as well as the alveolar bone height and the alveolar ridge width were measured in Göttingen Minipigs aged 12, 17 and 21 months. Our null hypothesis assumes that the age and the body mass have an influence on the parameters measured. The study found that the volume, length and depth of the mandibular canal all increase with age. The width of the canal does not change significantly with age. The body mass does not have an influence on any of the measured parameters. The increase in canal volume appears to be due to loss of deep spongy bone in the posterior premolar and molar regions. This reduces the available space for dental implantations, negatively affecting implant stability and potentially the integrity of the inferior alveolar neurovascular bundle. Dynamic anatomical changes occur until 21 months. On ethical grounds, using minipigs younger than 21 months in experimental implant dentistry is inadvisable. Paradoxically the measurements of the 12 months old pigs indicate a closer alignment of their mandibular anatomy to that of humans suggesting that they may be better models for implant studies. Given the variability in mandibular canal dimensions in similar age cohorts, the use of imaging techniques is essential for the selection of individual minipigs for dental prosthetic interventions and thus higher success rates.

  11. Ab-initio calculation and experimental observation of room temperature ferromagnetism in 50 keV nitrogen implanted rutile TiO2

    Science.gov (United States)

    Luitel, Homnath; Chakrabarti, Mahuya; Sarkar, A.; Dechoudhury, S.; Bhowmick, D.; Naik, V.; Sanyal, D.

    2018-02-01

    Room temperature magnetic properties of 50 keV N4+ ion beam implanted rutile TiO2 have been theoretically and experimentally studied. Ab-initio calculation under the frame work of density functional theory has been carried out to study the magnetic properties of the different possible nitrogen related defects in TiO2. Spin polarized density of states calculation suggests that both Ninst and NO can induce ferromagnetic ordering in rutile TiO2. In both cases the 2p orbital electrons of nitrogen atom give rise to the magnetic moment in TiO2. The possibility of the formation of N2 molecule in TiO2 system is also studied but in this case no significant magnetic moment has been observed. The magnetic measurements, using SQUID magnetometer, results a ferromagnetic ordering even at room temperature for the 50 keV N4+ ion beam implanted rutile TiO2.

  12. The metabolism of 32P-CP-PLLA seed implanted in the liver and its damage to the normal liver tissue: a study in the experimental dogs

    International Nuclear Information System (INIS)

    Tan Zhongbao; Liu Lu; Guo Jinhe; Zhu Guangyu; Wang Fuan; Nie Qi; Gao Hailin; Teng Gaojun

    2010-01-01

    Objective: To investigate the effects of intratumoral implantation of 32 P -CP-PLLA seeds on the normal canine liver tissue and to explore the metabolism of 32 P-CP-PLLA seeds implanted in the liver of experimental dogs. Methods: Twelve beagles were enrolled in this study. The dogs were randomly and equally divided into four groups: group A (185 MBq), group B (370 MBq), group C (740 MBq) and group D (0 MBq). By using laparotomy procedure 32 P-CP-PLLA seeds were implanted into dog's liver. CT scan was performed before operation as well as before the dog was sacrificed. All dogs were sacrificed three months after the implantation. Before the procedure and 1, 2, 4, 8 and 12 weeks after the procedure the blood tests and serum biochemical tests were conducted. One dog from group B and group C was selected respectively and was fed in a metabolic cage. Within one month after the procedure the cpm in feces and in urine was determined every 24 hours. One dog was picked out from each of the three groups and was punctured to get its liver tissue for pathologic exam each time at 1, 2, 4, 8 and 12 weeks after the implantation, and SPECT imaging was also performed at the same time. Pathologic study, both macroscopic and microscopic (including optical and electronic microscopy) was made to observe the liver damage after the dog was sacrificed. The statistical analysis was processed by using SPSS 13.0 software and the measuring data were expressed with mean ± standard deviation (x ± s). Results: Two months after the procedure, serological examination found that the serum alkaline phosphatase (BKP) in both group B and group C was significantly higher than that in other groups, the difference was statistically significant (P 32 P-CP-PLLA seeds was manifested as a spherical lesion which was encysted by a layer of fibrous tissue with an edematous zone peripherally. Conclusion: The implantation of 32 P-CP-PLLA seeds in dog's liver causes only localized hepatic damage with no general

  13. Role of tissue engineered collagen based tridimensional implant on the healing response of the experimentally induced large Achilles tendon defect model in rabbits: a long term study with high clinical relevance.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali

    2013-05-14

    Tendon injury is one of the orthopedic conditions poses with a significant clinical challenge to both the surgeons and patients. The major limitations to manage these injuries are poor healing response and development of peritendinous adhesions in the injured area. This study investigated the effectiveness of a novel collagen implant on tendon healing in rabbits. Seventy five mature White New-Zealand rabbits were divided into treated (n = 55) and control (n = 20) groups. The left Achilles tendon was completely transected and 2 cm excised. The defects of the treated animals were filled with collagen implants and repaired with sutures, but in control rabbits the defects were sutured similarly but the gap was left untreated. Changes in the injured and normal contralateral tendons were assessed weekly by measuring the diameter, temperature and bioelectrical characteristics of the injured area. Clinical examination was done and scored. Among the treated animals, small pilot groups were euthanized at 5, 10, 15, 20, 30, 40 and 60 (n = 5 at each time interval) and the remainder (n = 20) and the control animals at 120 days post injury (DPI). The lesions of all animals were examined at macroscopic and microscopic levels and the dry matter content, water delivery and water uptake characteristics of the lesions and normal contralateral tendons of both groups were analyzed at 120 DPI. This novel collagen implant was biodegradable, biocompatible and possibly could be considered as a substitute for auto and allografts in clinical practice in near future.

  14. Harnessing Nanotopography to Enhance Osseointegration of Clinical Orthopedic Titanium Implants—An in Vitro and in Vivo Analysis

    Directory of Open Access Journals (Sweden)

    Vitali Goriainov

    2018-04-01

    Full Text Available Despite technological advancements, further innovations in the field of orthopedics and bone regeneration are essential to meet the rising demands of an increasing aging population and associated issues of disease, injury and trauma. Nanotopography provides new opportunities for novel implant surface modifications and promises to deliver further improvements in implant performance. However, the technical complexities of nanotopography fabrication and surface analysis have precluded identification of the optimal surface features to trigger osteogenesis. We herein detail the osteoinductive potential of discrete nanodot and nanowire nanotopographies. We have examined the ability of modified titanium and titanium alloy (Ti64 surfaces to induce bone-specific gene activation and extracellular matrix protein expression in human skeletal stem cells (SSCs in vitro, and de novo osteogenic response within a murine calvarial model in vivo. This study provides evidence of enhanced osteogenic response to nanowires 300 surface modifications, with important implications for clinical orthopedic application.

  15. iPad apps for orthopedic surgeons.

    Science.gov (United States)

    Franko, Orrin I; Bhola, Siddharth

    2011-12-01

    The development and distribution of mobile applications, or apps, designed for medical professionals and patients is quickly expanding, and within this group are apps designed specifically for orthopedic use. Currently, the most popular mobile apps are sponsored by private companies and focus on delivering device-specific information. If this trend toward the use of privately funded educational materials continues, regulations may need to be established to ensure that the information provided is accurate, honest, and supported by peer-reviewed literature. It will likely be the responsibility of the orthopedic community to ensure that the development and use of these apps has appropriate oversight and validation as they are incorporated into clinical practice and training. Copyright © 2011, SLACK Incorporated.

  16. Overview of Implant Infections in Orthopaedics Department: Retrospective Study

    Directory of Open Access Journals (Sweden)

    Tugrul Bulut

    2014-12-01

    Full Text Available In this study, our aim was to evaluate the antibiotic susceptibility of bacteria isolated from orthopedic implant infections. Within two years operated 1996 patients in an orthopedics and traumatology clinic were retrospectively investigated. Seventy-six (76/1996, 3.8% orthopedic implant infections were detected. Isolated bacteria and their antibiotic susceptibility patterns were analyzed. The bacteries isolated from implant related infections and antibiotic sensitivity patterns were evaluated retrospectively in our orthopaedics and traumatology clinic. Staphylococcus aureus was the predominant organism (30.3%. Gram negative bacterias were isolated in 65.8% of our patients. No resistance was determined against vancomycin and linezolid in gram positive bacterias. Imipenem, amicasin and cefepim was seen as the most effective antibiotics for gram negative bacterias.

  17. Methods of orthopedic treatment of dentition defects

    Directory of Open Access Journals (Sweden)

    Konnov V.V.

    2016-09-01

    Full Text Available The article is devoted to the methods of orthopedic treatment of dentition defects. To restore the functionality and individual aesthetic standards of dental system, with different types of partial loss of teeth, depending on the anatomical and topographical conditions, various kinds of dental prosthesis designs are used in the oral cavity: non-removable (bridges, cantilever, adhesive dentures and removable (laminar and clasp dental prostheses, as well as their combinations.

  18. Level of evidence gap in orthopedic research.

    Science.gov (United States)

    Baldwin, Keith D; Bernstein, Joseph; Ahn, Jaimo; McKay, Scott D; Sankar, Wudbhav N

    2012-09-01

    Level of evidence is the most widely used metric for the quality of a publication, but instances exist in which a Level I study is neither feasible nor desirable. The goal of this study was to evaluate the level of evidence gap in current orthopedic research, which the authors defined as the disparity between the level of evidence that would be required to optimally answer the primary research question and the level of evidence that was actually used. Five orthopedic surgeons (K.D.B., J.B., J.A., S.D.M., W.N.S.) evaluated blinded articles from the first 6 months of 2010 in the Journal of Bone and Joint Surgery (American Volume) (JBJS-Am), classifying the study type and design and extracting a primary research question from each article. Each evaluator then defined the study type and method, along with the level of evidence that would ideally be used to address the primary research question. The level of evidence gap was then calculated by subtracting the actual level of evidence of the manuscript from the level of evidence of the idealized study. Of the 64 JBJS-Am manuscripts eligible for analysis, the average level of evidence was between Level II and III (mean, 2.73). The average level of evidence gap was 1.06 compared with the JBJS-Am-designated level of evidence and 1.28 compared with the evaluators' assessment. Because not all questions require Level I studies, level of evidence alone may not be the best metric for the quality of orthopedic surgery literature. Instead, the authors' concept of a level of evidence gap may be a better tool for assessing the state of orthopedic research publications. Copyright 2012, SLACK Incorporated.

  19. An advanced simulator for orthopedic surgical training.

    Science.gov (United States)

    Cecil, J; Gupta, Avinash; Pirela-Cruz, Miguel

    2018-02-01

    The purpose of creating the virtual reality (VR) simulator is to facilitate and supplement the training opportunities provided to orthopedic residents. The use of VR simulators has increased rapidly in the field of medical surgery for training purposes. This paper discusses the creation of the virtual surgical environment (VSE) for training residents in an orthopedic surgical process called less invasive stabilization system (LISS) surgery which is used to address fractures of the femur. The overall methodology included first obtaining an understanding of the LISS plating process through interactions with expert orthopedic surgeons and developing the information centric models. The information centric models provided a structured basis to design and build the simulator. Subsequently, the haptic-based simulator was built. Finally, the learning assessments were conducted in a medical school. The results from the learning assessments confirm the effectiveness of the VSE for teaching medical residents and students. The scope of the assessment was to ensure (1) the correctness and (2) the usefulness of the VSE. Out of 37 residents/students who participated in the test, 32 showed improvements in their understanding of the LISS plating surgical process. A majority of participants were satisfied with the use of teaching Avatars and haptic technology. A paired t test was conducted to test the statistical significance of the assessment data which showed that the data were statistically significant. This paper demonstrates the usefulness of adopting information centric modeling approach in the design and development of the simulator. The assessment results underscore the potential of using VR-based simulators in medical education especially in orthopedic surgery.

  20. Proximal spinal muscular atrophy: current orthopedic perspective

    Directory of Open Access Journals (Sweden)

    Haaker G

    2013-11-01

    Full Text Available Gerrit Haaker, Albert Fujak Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany Abstract: Spinal muscular atrophy (SMA is a hereditary neuromuscular disease of lower motor neurons that is caused by a defective "survival motor neuron" (SMN protein that is mainly associated with proximal progressive muscle weakness and atrophy. Although SMA involves a wide range of disease severity and a high mortality and morbidity rate, recent advances in multidisciplinary supportive care have enhanced quality of life and life expectancy. Active research for possible treatment options has become possible since the disease-causing gene defect was identified in 1995. Nevertheless, a causal therapy is not available at present, and therapeutic management of SMA remains challenging; the prolonged survival is increasing, especially orthopedic, respiratory and nutritive problems. This review focuses on orthopedic management of the disease, with discussion of key aspects that include scoliosis, muscular contractures, hip joint disorders, fractures, technical devices, and a comparative approach of conservative and surgical treatment. Also emphasized are associated complications including respiratory involvement, perioperative care and anesthesia, nutrition problems, and rehabilitation. The SMA disease course can be greatly improved with adequate therapy with established orthopedic procedures in a multidisciplinary therapeutic approach. Keywords: spinal muscular atrophy, scoliosis, contractures, fractures, lung function, treatment, rehabilitation, surgery, ventilation, nutrition, perioperative management

  1. [Orthopedics and patients under national socialism dictatorship].

    Science.gov (United States)

    Thomann, K D; Rauschmann, M

    2001-10-01

    The 12-year dictatorship of National Socialism represents a decisive event in the history of orthopedics in Germany. Treatment and care was limited to those patients whose prognosis promised their reintegration into the work force. Those orthopedic patients with mental and psychological handicaps no longer came under the care of orthopedists and were potential candidates for annihilation. Despite concerted efforts to the contrary, as can be gleaned from the lists of topics at the annual meetings, the prevailing political circumstances encumbered scientific activities. The almost total isolation from international contacts had a negative effect. Orthopedists were hindered in their work by the law on sterilization, which provided for sterilization in cases of severe physical deformity. Some orthopedists even considered the presence of hip dysplasia to be an indication. The roles played by Georg Hohmann, Hellmut Eckhardt, Lothar Kreuz, and other leading orthopedists are described in detail. It can be regarded as certain that Hohmann and Eckhardt were able to prevent dire consequences for their orthopedic patients and the profession by cautious tactics. The ethnical problems of involvement with National Socialism are thoroughly discussed.

  2. Influence of Palatal Coverage and Implant Distribution on Implant Strain in Maxillary Implant Overdentures.

    Science.gov (United States)

    Takahashi, Toshihito; Gonda, Tomoya; Mizuno, Yoko; Fujinami, Yozo; Maeda, Yoshinobu

    2016-01-01

    Maxillary implant overdentures are often used in clinical practice. However, there is no agreement or established guidelines regarding prosthetic design or optimal implant placement configuration. The purpose of this study was to examine the influence of palatal coverage and implant number and distribution in relation to impact strain under maxillary implant overdentures. A maxillary edentulous model with implants and experimental overdentures with and without palatal coverage was fabricated. Four strain gauges were attached to each implant, and they were positioned in the anterior, premolar, and molar areas. A vertical occlusal load of 98 N was applied through a mandibular complete denture, and the implant strains were compared using one-way analysis of variance (P = .05). The palatolabial strain was much higher on anterior implants than on other implants in both denture types. Although there was no significant difference between the strain under dentures with and without palatal coverage, palateless dentures tended to result in higher implant strain than dentures with palatal coverage. Dentures supported by only two implants registered higher strain than those supported by four or six implants. Implants under palateless dentures registered higher strain than those under dentures with palatal coverage. Anterior implants exhibited higher palatolabial strain than other implants regardless of palatal coverage and implant configuration; it is therefore recommended that maxillary implant overdentures should be supported by six implants with support extending to the distal end of the arch.

  3. Light microscopic identification and semiquantification of polyethylene particles in methylmethacrylate and paraffin-embedded experimental bone implant specimens

    DEFF Research Database (Denmark)

    Rahbek, O; Kold, S; Overgaard, S

    2005-01-01

    The aim of this study was to evaluate the identification of polyethylene (PE) particles in relatively thick methylmethacrylate (MMA) sections widely used in bone implant research. The sensitivity and specificity were compared between decalcified paraffin-embedded oil red O (ORO) stained and MMA-e...

  4. Effect of membranes and porous hydroxyapatite on healing in bone defects around titanium dental implants. An experimental study in monkeys

    DEFF Research Database (Denmark)

    Gotfredsen, K; Warrer, K; Hjørting-Hansen

    1991-01-01

    The purpose of the present study was to examine the effect of treating bony craters around titanium dental implant with polytetrafluoroethylene membranes (PTFE), with and without grafting of hydroxyapatite (HA), and with HA alone. 4 standardized bone defects were prepared in the alveolar ridge...

  5. A chlorhexidine-releasing epoxy-based coating on titanium implants prevents Staphylococcus aureus experimental biomaterial-associated infection

    NARCIS (Netherlands)

    Riool, M.; Dirks, A. J.; Jaspers, V.; de Boer, L.; Loontjens, T. J.; van der Loos, C. M.; Florquin, S.; Apachitei, I.; Rijk, L. N.; Keul, H. A.; Zaat, S. A.

    2017-01-01

    Prevention of biomaterial-associated infections (BAI) remains a challenging problem, in particular due to the increased risk of resistance development with the current antibiotic-based strategies. Metallic orthopaedic devices, such as non-cemented implants, are often inserted under high mechanical

  6. Electrochemical coating of dental implants with anodic porous titania for enhanced osteointegration

    Directory of Open Access Journals (Sweden)

    Amirreza Shayganpour

    2015-11-01

    Full Text Available Clinical long-term osteointegration of titanium-based biomedical devices is the main goal for both dental and orthopedical implants. Both the surface morphology and the possible functionalization of the implant surface are important points. In the last decade, following the success of nanostructured anodic porous alumina, anodic porous titania has also attracted the interest of academic researchers. This material, investigated mainly for its photocatalytic properties and for applications in solar cells, is usually obtained from the anodization of ultrapure titanium. We anodized dental implants made of commercial grade titanium under different experimental conditions and characterized the resulting surface morphology with scanning electron microscopy equipped with an energy dispersive spectrometer. The appearance of nanopores on these implants confirm that anodic porous titania can be obtained not only on ultrapure and flat titanium but also as a conformal coating on curved surfaces of real objects made of industrial titanium alloys. Raman spectroscopy showed that the titania phase obtained is anatase. Furthermore, it was demonstrated that by carrying out the anodization in the presence of electrolyte additives such as magnesium, these can be incorporated into the porous coating. The proposed method for the surface nanostructuring of biomedical implants should allow for integration of conventional microscale treatments such as sandblasting with additive nanoscale patterning. Additional advantages are provided by this material when considering the possible loading of bioactive drugs in the porous cavities.

  7. Hydroxyapatite electrodeposition on anodized titanium nanotubes for orthopedic applications

    Energy Technology Data Exchange (ETDEWEB)

    Parcharoen, Yardnapar [Department of Biological Engineering, Faculty of Engineering, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand); Kajitvichyanukul, Puangrat [Center of Excellence on Environmental Research and Innovation, Faculty of Engineering, Naresuan University, Phitsanulok (Thailand); Sirivisoot, Sirinrath [Department of Biological Engineering, Faculty of Engineering, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand); Termsuksawad, Preecha, E-mail: preecha.ter@kmutt.ac.th [Division of Materials Technology, School of Energy, Environment and Materials, King Mongkut' s University of Technology Thonburi, 126 Pracha Uthit Rd., Bang Mod, ThungKhru, Bangkok 10140 (Thailand)

    2014-08-30

    Highlights: • We found that different anodization time of titanium significantly effects on nanotube length which further impacts adhesion strength of hydroxyapatite coating layers. • Adhesion strength of Hydroxyapatite (HA) coated on titanium dioxide nanotubes is better than that of HA coated on titanium plate. • Hydroxyapatite coated on titanium dioxide nanotubes showed higher cell density and better spreading of MC3T3-E1 cells (bone-forming cells) than that coated on titanium plate surface. - Abstract: Nanotubes modification for orthopedic implants has shown interesting biological performances (such as improving cell adhesion, cell differentiation, and enhancing osseointegration). The purpose of this study is to investigate effect of titanium dioxide (TiO{sub 2}) nanotube feature on performance of hydroxyapatite-coated titanium (Ti) bone implants. TiO{sub 2} nanotubes were prepared by anodization using ammonium fluoride electrolyte (NH{sub 4}F) with and without modifiers (PEG400 and Glycerol) at various potential forms, and times. After anodization, the nanotubes were subsequently annealed. TiO{sub 2} nanotubes were characterized by scanning electron microscope and X-ray diffractometer. The amorphous to anatase transformation due to annealing was observed. Smooth and highly organized TiO{sub 2} nanotubes were found when high viscous electrolyte, NH{sub 4}F in glycerol, was used. Negative voltage (−4 V) during anodization was confirmed to increase nanotube thickness. Length of the TiO{sub 2} nanotubes was significantly increased by times. The TiO{sub 2} nanotube was electrodeposited with hydroxyapatite (HA) and its adhesion was estimated by adhesive tape test. The result showed that nanotubes with the tube length of 560 nm showed excellent adhesion. The coated HA were tested for biological test by live/dead cell straining. HA coated on TiO{sub 2} nanotubes showed higher cells density, higher live cells, and more spreading of MC3T3-E1 cells than that

  8. Sol-Gel Derived Hydroxyapatite Coating on Mg-3Zn Alloy for Orthopedic Application

    Science.gov (United States)

    Singh, Sanjay; Manoj Kumar, R.; Kuntal, Kishor Kumar; Gupta, Pallavi; Das, Snehashish; Jayaganthan, R.; Roy, Partha; Lahiri, Debrupa

    2015-04-01

    In recent years, magnesium and its alloys have gained a lot of interest as orthopedic implant constituents because their biodegradability and mechanical properties are closer to that of human bone. However, one major concern with Mg in orthopedics is its high corrosion rate that results in the reduction of mechanical integrity before healing the bone tissue. The current study evaluates the sol-gel-derived hydroxyapatite (HA) coating on a selected Mg alloy (Mg-3Zn) for decreasing the corrosion rate and increasing the bioactivity of the Mg surface. The mechanical integrity of the coating is established as a function of the surface roughness of the substrate and the sintering temperature of the coating. Coating on a substrate roughness of 15-20 nm and sintering at 400°C shows the mechanical properties in similar range of bone, thus making it suitable to avoid the stress-shielding effect. The hydroxyapatite coating on the Mg alloy surface also increases corrosion resistance very significantly by 40 times. Bone cells are also found proliferating better in the HA-coated surface. All these benefits together establish the candidature of sol-gel HA-coated Mg-3Zn alloy in orthopedic application.

  9. Influence of orthopedic reinforced gloves versus double standard gloves on contamination events during small animal orthopedic surgery.

    Science.gov (United States)

    Hayes, Galina; Singh, Ameet; Gibson, Tom; Moens, Noel; Oblak, Michelle; Ogilvie, Adam; Reynolds, Debbie

    2017-10-01

    To determine the influence of orthopedic reinforced gloves on contamination events during small animal orthopedic surgery. Prospective randomized controlled trial SAMPLE POPULATION: Two hundred and thirty-seven pairs of orthopedic gloves (474 gloves) and 203 pairs of double standard gloves (812 gloves) worn during 193 orthopedic procedures. Primary and assistant surgeons were randomized to wear either orthopedic reinforced gloves or double gloves. Gloves were leak tested to identify perforations at the end of procedures. Perforations detected intraoperatively or postoperatively were recorded. A contamination event was defined as at least one perforation on either hand for orthopedic reinforced gloves, or a perforation of both the inner and outer glove on the same hand for double gloves. Baseline characteristics between the 2 intervention groups were similar. There was no difference in contamination events between the double-gloved and orthopedic gloved groups (OR = 0.95, 95% CI = 0.49-1.87, P = .89). The same percentage of contamination events (8% glove pairs used) occurred in the double gloved group (17 contamination events) and in the orthopedic gloved group (19 contamination events). The odds of a contamination event increased by 1.02 (95% CI 1.01-1.03, P contamination events in small animal orthopedic procedures. Surgeons reluctant to double glove due to perceptions of decreased dexterity and discomfort may safely opt for wearing orthopedic gloves, which may improve their compliance. © 2017 The American College of Veterinary Surgeons.

  10. Nanotechnology-enhanced orthopedic materials fabrications, applications and future trends

    CERN Document Server

    Yang, Lei

    2015-01-01

    Nanotechnology-Enhanced Orthopedic Materials provides the latest information on the emergence and rapid development of nanotechnology and the ways it has impacted almost every aspect of biomedical engineering. This book provides readers with a comprehensive overview of the field, focusing on the fabrication and applications of these materials, presenting updated, practical, and systematic knowledge on the synthesis, processing, and modification of nanomaterials, along with the rationale and methodology of applying such materials for orthopedic purposes. Topics covered include a wide range of orthopedic material formulations, such as ceramics, metals, polymers, biomolecules, and self-assemblies. Final sections explore applications and future trends in nanotechnology-enhanced orthopedic materials. Details practical information on the fabrication and modification of new and traditional orthopedic materials Analyzes a wide range of materials, designs, and applications of nanotechnology for orthopedics Investigate...

  11. Orthopedic complications of linear morphea: Implications for early interdisciplinary care.

    Science.gov (United States)

    Schoch, Jennifer J; Schoch, Bradley S; Werthel, Jean David; McIntosh, Amy L; Davis, Dawn M R

    2018-01-01

    Linear morphea of the limb primarily affects children, and extracutaneous manifestations are common. Orthopedic surgeons are often essential in the care of patients with linear morphea, yet there are few reports outlining specific orthopedic complications in this population. We sought to improve the understanding of orthopedic complications in linear morphea of the limb. Between 1999 and 2014, 51 children were evaluated for linear morphea of an extremity. Twenty-six (51%) had documented orthopedic manifestations. Outcome measures included limb length discrepancy, angular malalignment, limb atrophy, and orthopedic surgical intervention. Joint contractures were most common, affecting 88% of patients, followed by limb atrophy, angular deformity, and limb length discrepancy; 14% required surgical intervention. Despite the use of systemic immunosuppressive therapy in many patients, approximately half of patients with linear morphea of an extremity have orthopedic disease. Early orthopedist involvement is crucial to improve limb alignment and preserve function. © 2017 Wiley Periodicals, Inc.

  12. Bone Ceramic® at Implants Installed Immediately into Extraction Sockets in the Molar Region: An Experimental Study in Dogs.

    Science.gov (United States)

    Pereira, Flávia Priscila; Hochuli-Vieira, Eduardo; Maté Sánchez de Val, José E; De Santis, Enzo; Salata, Luiz Antonio; Botticelli, Daniele

    2016-04-01

    The aim of this paper was to study the healing of 1-1.4 mm wide buccal defects at implants placed immediately into extraction sockets (IPIES) filled with a mixture of synthetic hydroxyapatite (HA) 60% and beta-tricalciumphosphate (TCP) 40% or left with the clot alone and both covered with collagen membranes. Eight Labrador dogs were used and implants were placed immediately into the extraction sockets of the first molar bilaterally. A mixture of synthetic HA 60% and beta-TCP 40% at the test or the clot alone at the control sites were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membrane and a non-submerged healing was allowed. After 4 months, the animals were euthanized, biopsies harvested and processed for histomorphometric analysis. At the time of installation, residual buccal defects occurred that were 1.1 mm and 1.4 mm wide and 3 mm and 4 mm deep at the control and test sites, respectively. After 4 months of healing, the top of the bony crest and the coronal level of osseointegration were located respectively at 0.1 ± 1.8 mm and 1.5 ± 1.8 mm at the test, and 0.6 ± 1.6 mm and 1.2 ± 0.7 mm at the control sites apically to the implant shoulder. Bone-to-implant contact at the buccal aspect was 34.9 ± 25.9% and 36.4 ± 17.3% at the test and control sites, respectively. No statistically significant differences were found between test and control sites for any of the variables analyzed at the buccal aspects. The use of a mixture of synthetic HA 60% and beta-TCP 40% to fill residual buccal defects 1-1.4 mm wide at IPIES did not improve significantly the results of healing. © 2015 Wiley Periodicals, Inc.

  13. A histologic analysis of the effects of stainless steel and titanium implants adjacent to tendons: an experimental rabbit study.

    Science.gov (United States)

    Nazzal, Adam; Lozano-Calderón, Santiago; Jupiter, Jesse B; Rosenzweig, Jaime S; Randolph, Mark A; Lee, Sang Gil P

    2006-09-01

    The current trend is to treat distal radius fractures with open reduction and internal fixation with either titanium or stainless steel plates. Both provide stable fixation; however, there is minimal evidence concerning the soft-tissue response to these materials. Our objective was to evaluate the response of adjacent extensor tendons to titanium and stainless steel in a rabbit in vivo model and to evaluate the influence of time. Forty rabbits were divided into 5 groups of 8 rabbits each. Groups I and II had unilateral osteotomy of the distal radius followed by dorsal fixation with titanium and stainless steel plates, respectively. Groups III and IV had fixation with titanium and stainless steel, respectively, but without osteotomy. Group V had surgical dissection without osteotomy or plates. Two animals per group were killed at 1, 4, 12, and 24 weeks. The specimens (distal radius, plate, overlying soft tissue, and extensor tendon) were harvested en bloc for histologic analysis. For interface preservation between implant and tissues the specimens were embedded in methylmethacrylate, sectioned, and stained with hematoxylin-eosin. Histologic analysis showed a fibrous tissue layer formed over both implants between the plate and the overlying extensor tendons in the groups treated with plating independently of the material and the presence or absence of osteotomy. This fibrous layer contained the majority of debris. Metallic particles were not observed in the tendon or muscle substance of any animals; however, they were visualized in the tenosynovium. Hematoxylin-eosin-stained sections of groups I through IV showed proliferative fibroblasts and metallic particles; however, this layer was not observed in group V. Statistical analysis did not show differences between the groups regarding the number of cells or metallic particles. Our results indicate that both implants generated adjacent reactive inflammatory tissue and particulate debris. There was no difference in cell

  14. A Fully Implantable Stimulator With Wireless Power and Data Transmission for Experimental Investigation of Epidural Spinal Cord Stimulation.

    Science.gov (United States)

    Xu, Qi; Hu, Dingyin; Duan, Bingyu; He, Jiping

    2015-07-01

    Epidural spinal cord stimulation (ESCS) combined with partial weight-bearing therapy (PWBT) has been shown to facilitate recovery of functional walking for individuals after spinal cord injury (SCI). The investigation of neural mechanisms of recovery from SCI under this treatment has been conducted broadly in rodent models, yet a suitable ESCS system is still unavailable. This paper describes a practical, programmable, and fully implantable stimulator for laboratory research on rats to explore fundamental neurophysiological principles for functional recovery after SCI. The ESCS system is composed of a personal digital assistant (PDA), an external controller, an implantable pulse generator (IPG), lead extension, and stimulating electrodes. The stimulation parameters can be programmed and adjusted through a graphical user interface on the PDA. The external controller is placed on the rat back and communicates with the PDA via radio-frequency (RF) telemetry. An RF carrier from the class-E power amplifier in the external controller provides both data and power for the IPG through an inductive link. The IPG is built around a microcontroller unit to generate voltage-regulated pulses delivered to the bipolar electrode for ESCS in rats. The encapsulated IPG measures 22 mm × 23 mm × 7 mm with a mass of  ∼  3.78 g. This fully implantable batteryless stimulator provided a simplified and efficient method to carry out chronic experiments in untethered animals for medical electro-neurological research.

  15. In vitro characterizations of mesoporous hydroxyapatite as a controlled release delivery device for VEGF in orthopedic applications.

    Science.gov (United States)

    Poh, Chye Khoon; Ng, Suxiu; Lim, Tee Yong; Tan, Hark Chuan; Loo, Joachim; Wang, Wilson

    2012-11-01

    Following bone implant surgery, prolonged ischemic conditions at the implant site often result in postsurgical complications like failure of osseointegration at the bone-implant interface which can lead to implant failure. Thus, restoration of the vascular supply is paramount to the proper development of the bone. High surface area mesostructured materials have been shown to be attractive candidates for bone regeneration to enhance cell adhesion and cell proliferation. This study uses hydroxyapatite, a naturally occurring mineral in the bone, fabricated to a range of suitable pore sizes, infused with vascular endothelial growth factor (VEGF), to be progressively released to stimulate revascularization. In this study, several characterizations including nitrogen adsorption analysis, Fourier-transformed infrared spectroscopy, X-ray diffraction, field emission scanning electron microscope, and transmission electron microscope were used to evaluate the synthesized mesoporous hydroxyapatite (MHA). The results showed that MHA can gradually release VEGF for enhancing revascularization, which is beneficial for orthopedic applications. Copyright © 2012 Wiley Periodicals, Inc.

  16. New orthopaedic implant management tool for computer-assisted planning, navigation, and simulation: from implant CAD files to a standardized XML-based implant database.

    Science.gov (United States)

    Sagbo, S; Blochaou, F; Langlotz, F; Vangenot, C; Nolte, L-P; Zheng, G

    2005-01-01

    Computer-Assisted Orthopaedic Surgery (CAOS) has made much progress over the last 10 years. Navigation systems have been recognized as important tools that help surgeons, and various such systems have been developed. A disadvantage of these systems is that they use non-standard formalisms and techniques. As a result, there are no standard concepts for implant and tool management or data formats to store information for use in 3D planning and navigation. We addressed these limitations and developed a practical and generic solution that offers benefits for surgeons, implant manufacturers, and CAS application developers. We developed a virtual implant database containing geometrical as well as calibration information for orthopedic implants and instruments, with a focus on trauma. This database has been successfully tested for various applications in the client/server mode. The implant information is not static, however, because manufacturers periodically revise their implants, resulting in the deletion of some implants and the introduction of new ones. Tracking these continuous changes and keeping CAS systems up to date is a tedious task if done manually. This leads to additional costs for system development, and some errors are inevitably generated due to the huge amount of information that has to be processed. To ease management with respect to implant life cycle, we developed a tool to assist end-users (surgeons, hospitals, CAS system providers, and implant manufacturers) in managing their implants. Our system can be used for pre-operative planning and intra-operative navigation, and also for any surgical simulation involving orthopedic implants. Currently, this tool allows addition of new implants, modification of existing ones, deletion of obsolete implants, export of a given implant, and also creation of backups. Our implant management system has been successfully tested in the laboratory with very promising results. It makes it possible to fill the current gap

  17. Nursing documentation and length of stay in orthopedic surgery

    NARCIS (Netherlands)

    Paans, Wolter; Krijnen, Wim

    2016-01-01

    Nursing outcome calculation, and future possibilities. An example in orthopedic specialty nursing. Comparing nursing diagnoses in hip prosthesis patients and knee prosthesis patients in a Dutch hospital.

  18. Medical Crowdfunding for Patients Undergoing Orthopedic Surgery.

    Science.gov (United States)

    Durand, Wesley M; Johnson, Joseph R; Eltorai, Adam E M; Daniels, Alan H

    2018-01-01

    Crowdfunding for medical expenses is growing in popularity. Through several websites, patients create public campaign profiles to which donors can contribute. Research on medical crowdfunding is limited, and there have been no studies of crowdfunding in orthopedics. Active medical crowdfunding campaigns for orthopedic trauma, total joint arthroplasty, and spine surgery were queried from a crowdfunding website. The characteristics and outcomes of crowdfunding campaigns were abstracted and analyzed. For this study, 444 campaigns were analyzed, raising a total of $1,443,528. Among the campaigns that received a donation, mean amount raised was $4414 (SE, $611). Multivariate analysis showed that campaigns with unspecified location (odds ratio, 0.26; P=.0008 vs West) and those for total joint arthroplasty (odds ratio, 0.35; P=.0003 vs trauma) had significantly lower odds of receipt of any donation. Description length was associated with higher odds of donation receipt (odds ratio, 1.13 per +100 characters; Pcrowdfunding may be disproportionately available to patients with specific diagnoses, those from specific regions, those who are able to craft a lengthy descriptive narrative, and those with access to robust digital social networks. Clinicians are likely to see a greater proportion of patients turning to crowdfunding as it grows in popularity. Patients may ask physicians for information about crowdfunding or request testimonials to support campaigns. Surgeons should consider their response to such requests individually. These findings shed light on the dynamics of medical crowdfunding and support robust personal and professional deliberation. [Orthopedics. 2018; 41(1):e58-e63.]. Copyright 2017, SLACK Incorporated.

  19. Ion implantation

    International Nuclear Information System (INIS)

    Dearnaley, Geoffrey

    1975-01-01

    First, ion implantation in semiconductors is discussed: ion penetration, annealing of damage, gettering, ion implanted semiconductor devices, equipement requirements for ion implantation. The importance of channeling for ion implantation is studied. Then, some applications of ion implantation in metals are presented: study of the corrosion of metals and alloys; influence or ion implantation on the surface-friction and wear properties of metals; hyperfine interactions in implanted metals

  20. Damage control in orthopedics and traumatology

    International Nuclear Information System (INIS)

    Martinez R, Alfredo

    2006-01-01

    The damage control allows the clinician to institute a rapid process that avoids early death from over aggressive treatment of an injury and lack of attention to the underlying physiological state of victim. This concept allows rapid control and support of the patients underlying physiological condition in an attempt to avoid the triad of death: bleeding, hypothermia and metabolic acidosis. We revised the several indications to damage control in orthopedics in the patients with polytrauma, isolated extremity injury as femur fracture, and the geriatric patients and crane cephalic trauma

  1. Imaging of orthopedic trauma and surgery

    International Nuclear Information System (INIS)

    Berquist, T.H.

    1985-01-01

    This book presents papers on imaging techniques for diagnosis of trauma of bones. A comparative evaluation is presented for planning of proper diagnosis and treatment. Various techniques discussed are routine radiography; computerized tomography, NMR imaging, angiography, ultrasonography; and use of radioisotopes. The mechanism of injury of bone joints of upper and lower limbs and spine is discussed after discussing the anatomy of each in the beginning of each paper. Topics titled are healing of fractures; fractures of pelvis; knee; shoulder; foot and ankle; fractures of humerus; stress fractures; and orthopedic radiology. Prosthesis use and plastic surgery of joints is also discussed

  2. Prevention of Infection in Orthopedic Prosthetic Surgery.

    Science.gov (United States)

    Chirca, Ioana; Marculescu, Camelia

    2017-06-01

    Total joint arthroplasty is a generally safe orthopedic procedure; however, infection is a potentially devastating complication. Multiple risk factors have been identified for development of prosthetic joint infections. Identification of patients at risk and preoperative correction of known risk factors, such as smoking, diabetes mellitus, anemia, malnutrition, and decolonization of Staphylococcus carriers, represent well-established actions to decrease the infection risk. Careful operative technique, proper draping and skin preparation, and appropriate selection and dosing of antimicrobials for perioperative prophylaxis are also very important in prevention of infection. Published by Elsevier Inc.

  3. Orthopedic Resident Anatomy Review Course: A Collaboration between Anatomists and Orthopedic Surgeons

    Science.gov (United States)

    DeFriez, Curtis B.; Morton, David A.; Horwitz, Daniel S.; Eckel, Christine M.; Foreman, K. Bo; Albertine, Kurt H.

    2011-01-01

    A challenge for new residents and senior residents preparing for board examinations is refreshing their knowledge of basic science disciplines, such as human gross anatomy. The Department of Orthopaedics at the University of Utah School of Medicine has for many years held an annual Orthopedic Resident Anatomy Review Course during the summer months…

  4. Magnetic resonance evaluation of luminal patency after polylactide stent implantation: an experimental study in a rabbit aorta model

    International Nuclear Information System (INIS)

    Hietala, Eeva-Maija; Salminen, Ulla-Stina; Harjula, Ari L.J.; Maasilta, Paula; Staahls, Anders; Vaelimaa, Tero; Kivisaari, Leena

    2003-01-01

    Intravascular metallic stents cause magnetic field distortions, disturbing luminal detection. Our aim was to evaluate the effect of polylactic acid (PLA) stents on magnetic resonance angiography (MRA). Biodegradable double spiral helical PLA stents (n=12) or stainless steel (SS) (n=6) stents were implanted into the infrarenal aortas of New Zealand White rabbits. All SS- and 6 PLA-stented animals as well as 6 non-operated control rabbits were imaged with gadolinium-enhanced MRA (1.5 T), and infrarenal aortic diameters (proximal, distal, and narrowest), together with the stent artifact, were measured. Six of the PLA-stented rabbits were followed up, and MRA was assessed at 2, 6, 9, and 12 months after the stent implantation. Image artifacts caused by the SS stents were visualized in all cases. The PLA stents caused no magnetic field distortion, allowing imaging of the underlying vessel including the vessel lumen. In the follow-up group of 6 rabbits with a PLA stent, 5 of 6 were patent at the end of the follow-up of 12 months. These stents allowed luminal detection at all time points, with no significant differences in aortic measurements emerging during the whole follow-up period. When immediately postoperatively scanned SS and PLA rabbits were compared with controls, no differences were observable in proximal diameters. Instead, the percentage of distal luminal loss was greater in the PLA-stented rabbits, as compared with SS stents (p<0.01). The PLA stenting in small vessels allows evaluation of luminal patency with MRA both immediately after implantation and during follow-up. (orig.)

  5. Pericytes for the treatment of orthopedic conditions.

    Science.gov (United States)

    James, Aaron W; Hindle, Paul; Murray, Iain R; West, Christopher C; Tawonsawatruk, Tulyapruek; Shen, Jia; Asatrian, Greg; Zhang, Xinli; Nguyen, Vi; Simpson, A Hamish; Ting, Kang; Péault, Bruno; Soo, Chia

    2017-03-01

    Pericytes and other perivascular stem cells are of growing interest in orthopedics and tissue engineering. Long regarded as simple regulators of angiogenesis and blood pressure, pericytes are now recognized to have MSC (mesenchymal stem cell) characteristics, including multipotentiality, self-renewal, immunoregulatory functions, and diverse roles in tissue repair. Pericytes are typified by characteristic cell surface marker expression (including αSMA, CD146, PDGFRβ, NG2, RGS5, among others). Although alone no marker is absolutely specific for pericytes, collectively these markers appear to selectively identify an MSC-like pericyte. The purification of pericytes is most well described as a CD146 + CD34 - CD45 - cell population. Pericytes and other perivascular stem cell populations have been applied in diverse orthopedic applications, including both ectopic and orthotopic models. Application of purified cells has sped calvarial repair, induced spine fusion, and prevented fibrous non-union in rodent models. Pericytes induce these effects via both direct and indirect mechanisms. In terms of their paracrine effects, pericytes are known to produce and secrete high levels of a number of growth and differentiation factors both in vitro and after transplantation. The following review will cover existing studies to date regarding pericyte application for bone and cartilage engineering. In addition, further questions in the field will be pondered, including the phenotypic and functional overlap between pericytes and culture-derived MSC, and the concept of pericytes as efficient producers of differentiation factors to speed tissue repair. Copyright © 2016. Published by Elsevier Inc.

  6. Disparities in internet use among orthopedic outpatients.

    Science.gov (United States)

    Walsh, Kenneth P; Rehman, Saqib; Goldhirsh, Jessie

    2014-02-01

    Internet access has lagged behind for patients with lower incomes and from certain ethnic groups. This study investigated the possible improvement of access to health-related information on the Internet for all patients in an urban outpatient setting, regardless of socioeconomic background. A 28-question survey was completed by 100 orthopedic outpatients evaluating associations between their age, ethnicity, income, or education level and their access to the Internet. The survey also examined how patients used the Internet to obtain information about their medical condition, their privacy concerns when conducting online research, and their use of mobile phones as a primary means of Internet access. The Internet was used by 57% of orthopedic outpatients in this urban setting. Internet access decreased with advancing age but increased with increasing income and education, findings consistent with similar studies. Despite the inability to identify an association between ethnicity and Internet access in this patient population, fewer Latinos (33%) than whites (67%) or African Americans (77%) sought information about their medical condition. Among patients who used a mobile phone as the primary method for online access, 74% were African American or Latino and 26% were white. This difference in mobile phone use for online access suggests that mobile phones have provided ethnic minorities with greater Internet access and thus may have narrowed the digital divide among the races. Copyright 2014, SLACK Incorporated.

  7. Hydroxyapatite-lignin composite as a metallic implant-bone tissue osseointegration improver: experimental study in dogs

    Directory of Open Access Journals (Sweden)

    Fabrício Luciani Valente

    2015-01-01

    Full Text Available The study aimed to evaluate biocompatibility, osteoconduction and osseointegration of a pasty composite of hydroxyapatite (20% and lignin (80% as a promoter of metal implant and bone tissue integration. An intramedullary Schanz pin was implanted in both tibias of fifteen bitches. In the left tibia, the pin was coated with the biomaterial at the time of surgery. Marrow cavity was also filled with the biomaterial. Right limb did not receive the biomaterial, then constituting the control group. Tibias were harvested from five animals at 8, 60 and 150 days after surgery; three of them were analyzed by histological and biomechanical assessment and the two remaining tibias by X-ray diffraction. Results showed that the biomaterial is biocompatible, with osteoconductivity and osseointegration properties. Histological analysis and diffractograms showed the presence of hydroxyapatite in samples in all periods, although the presence of organic material of low crystallinity was variable. There was no statistical difference in the forces required for removal of the biocompatibility, osteoconductivity and osseointegration, it was not able to promote a better intramedullary pin anchorage.

  8. Radioactive implant induced x-ray emission technique for noninvasive determination of iodine content in thyroid: experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Amano, R; Ando, A; Hiraki, T [Kanazawa Univ. (Japan). School of Allied Medical Professions; Tonami, N; Hisada, K [Kanazawa Univ. (Japan). School of Medicine

    1984-02-01

    A new technique, radioactive implant x-ray emission spectrometry to determine the in vivo iodine content of the human thyroid is proposed. The variations of counting rate and effective excitation efficiencies of I Ksub(..cap alpha..) (28.6 keV) with iodine content, thyroid volume and skin-thyroid distance were studied for the /sup 201/Tl source to examine the properties of excitation and photon attenuation. As a result, the gland depth and volume could be estimated from the peak ratios of 30.7 keV/167.6 keV and 28.6 keV/167.6 keV. Using a 1 MBq /sup 201/Tl implant source, the detectable minimum iodine concentration found was approximately 70 ..mu..g/g for 2000 s measuring time in the phantom experiment. The effectiveness of the RIXE technique is discussed. It was concluded that the /sup 201/Tl RIXE spectrometry might serve to determine the in vivo iodine content of the human thyroid.

  9. Radioactive implant induced x-ray emission technique for noninvasive determination of iodine content in thyroid: experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Amano, R; Tonami, N; Ando, A; Hiraki, T; Hisada, K

    1984-02-01

    A new technique, radioactive implant x-ray emission spectrometry to determine the in vivo iodine content of the human thyroid is proposed. The variations of counting rate and effective excitation efficiencies of I K alpha (28.6 keV) with iodine content, thyroid volume and skin-thyroid distance were studied for the /sup 201/Tl source to examine the properties of excitation and photon attenuation. As a result, the gland depth and volume could be estimated from the peak ratios of 30.7 keV/167.6 keV and 28.6 keV/167.6 keV. Using a 1 MBq /sup 201/Tl implant source, the detectable minimum iodine concentration found was approximately 70 micrograms/g for 2000 s measuring time in the phantom experiment. The effectiveness of the RIXE technique is discussed. It was concluded that the /sup 201/Tl RIXE spectrometry might serve to determine the in vivo iodine content of the human thyroid.

  10. Evaluation of the Surface Treatment on Bone Healing in a Transmucosal 1-mm Area of Implant Abutment: An Experimental Study in the Rabbit Tibia.

    Science.gov (United States)

    Gehrke, Sergio Alexandre; da Silva Neto, Ulisses Tavares

    2016-06-01

    The objective of the present study was to investigate the effect on bone tissue healing patterns in 1-mm area treated in the transmucosal surface of the abutment in the tibia of rabbits. Forty-six abutments were divided into two groups: control group (CG) with 14 abutments with smooth surface and experimental group (EG) with 32 abutments presenting a 1-mm area of the transmucosal surface treated through sandblasting with microparticles of titanium oxide followed by acid etching. Five samples of each group were analyzed using an optical laser profilometer for surface roughness characterization. Thirty-six Morse taper implants (3.5 mm in diameter and 7 mm in length) were inserted 1.5 mm subcrestal into the tibiae of nine rabbits. The implants were removed after 8, 10, and 12 weeks for histological analysis. The histological slides were prepared and analyzed qualitatively in relation to the new bone at the interface bone-abutment and quantitatively, in relation to bone height from the base of the implant. These data were computed and statistically compared inside the groups using analysis of variance and the U-test between groups for same time. Both groups exhibited bone growth in the direction and over the surface of the abutments, with good healing. However, the EG group showed an increased height of bone formation in the crestal direction, and highly significant differences were observed (p abutment with treatment of the surface facilitated the maintenance of bone height around the abutment compared with the same abutment with the totally smooth surface. © 2015 Wiley Periodicals, Inc.

  11. Miniscrew implant applications in contemporary orthodontics

    Directory of Open Access Journals (Sweden)

    Hong-Po Chang

    2014-03-01

    Full Text Available The need for orthodontic treatment modalities that provide maximal anchorage control but with minimal patient compliance requirements has led to the development of implant-assisted orthodontics and dentofacial orthopedics. Skeletal anchorage with miniscrew implants has no patient compliance requirements and has been widely incorporated in orthodontic practice. Miniscrew implants are now routinely used as anchorage devices in orthodontic treatment. This review summarizes recent data regarding the interpretation of bone data (i.e., bone quantity and quality obtained by preoperative diagnostic computed tomography (CT or by cone-beam computed tomography (CBCT prior to miniscrew implant placement. Such data are essential when selecting appropriate sites for miniscrew implant placement. Bone characteristics that are indications and contraindications for treatment with miniscrew implants are discussed. Additionally, bicortical orthodontic skeletal anchorage, risks associated with miniscrew implant failure, and miniscrew implants for nonsurgical correction of occlusal cant or vertical excess are reviewed. Finally, implant stability is compared between titanium alloy and stainless steel miniscrew implants.

  12. Quantifying He-point defect interactions in Fe through coordinated experimental and modeling studies of He-ion implanted single-crystal Fe

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xunxiang, E-mail: xunxianghu@berkeley.edu [Department of Nuclear Engineering, University of California, Berkeley, CA 94720-1730 (United States); Xu, Donghua; Wirth, Brian D. [Department of Nuclear Engineering, University of California, Berkeley, CA 94720-1730 (United States); Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996-2300 (United States)

    2013-11-15

    Understanding the effects of helium on the microstructural evolution and mechanical properties of structural materials are among the most challenging issues in fusion materials research. In this work, we combine thermal helium desorption spectroscopy (THDS) with positron annihilation spectroscopy (PAS) and a spatially dependent cluster dynamics model to investigate the energetics of helium-point defect interactions in helium-implanted single-crystal iron. The combination of modeling and thermal desorption measurements allows identification of the binding energies of small He–V clusters, the migration energy of single vacancy and possible mechanisms (e.g., shrinkage of He{sub 3}V{sub 2} clusters) responsible for measured Helium desorption peaks, and the effect of impurities (e.g., carbon) on these values. Furthermore, the model predicts the depth dependence of the helium and helium–vacancy clusters as a function of time and temperature during the thermal desorption measurement. Here, we report the THDS measurement results as a function of He implantation energy from 10 to 40 keV at a fluence level of 1 × 10{sup 15} He/cm{sup 2}, along with selected PAS measurements. The experimental results are compared to the modeling predictions to evaluate the extent to which self-consistent values of the He-point defect binding and interaction energies and diffusivities can explain the data.

  13. Cochlear implants and medical tourism.

    Science.gov (United States)

    McKinnon, Brian J; Bhatt, Nishant

    2010-09-01

    To compare the costs of medical tourism in cochlear implant surgery performed in India as compared to the United States. In addition, the cost savings of obtaining cochlear implant surgery in India were compare d to those of other surgical interventions obtained as a medical tourist. Searches were conducted on Medline and Google using the search terms: 'medical tourism', 'medical offshoring', 'medical outsourcing', 'cochlear implants' and 'cochlear implantation'. The information regarding cost of medical treatment was obtained from personal communication with individuals familiar with India's cochlear implantation medical tourism industry. The range of cost depended on length of stay as well as the device chosen. Generally the cost, inclusive of travel, surgery and device, was in the range of $21,000-30,000, as compared to a cost range of $40,000-$60,000 in the US. With the escalating cost of healthcare in the United States, it is not surprising that some patients would seek to obtain surgical care overseas at a fraction of the cost. Participants in medical tourism often have financial resources, but lack health insurance coverage. While cardiovascular and orthopedic surgery performed outside the United States in India at centers that cater to medical tourists are often performed at one-quarter to one-third of the cost that would have been paid in the United States, the cost differential for cochlear implants is not nearly as favorable.

  14. Laser speckle technology in stomatology. diagnostics of stresses and strains of hard biotissues and orthodontic and orthopedic structures

    Science.gov (United States)

    Denisova, Yu. L.; Bazylev, N. B.; Rubnikovich, S. P.; Fomin, N. A.

    2013-07-01

    We have investigated the formation and dynamics of speckle biofi elds formed by hard biotissues of the oral cavity irradiated with low-intensity radiation. We present experimental methods for diagnosing the stressed-strained state of the maxillodental system and orthodontic and orthopedic structures based on speckle technologies and crosscorrelation analysis of speckle biofi elds.

  15. Nuclear magnetic resonance imaging in orthopedics

    International Nuclear Information System (INIS)

    Peters, P.E.; Matthiass, H.H.; Reiser, M.

    1990-01-01

    NMR imaging (MR tomography) allows the non-invasive diagnostic evaluation of cartilage, ligaments, tendons and muscles of the limbs, joints and the vertebral spine. The images are characterized by a good spatial resolution, and in contrast to the X-ray CT, sectional images can be done in all planes, as well as three-dimensional image reconstructions. The book reviews the current state of the art and foreseeable developments of NMR imaging of the supporting and connective tissue, also discussing the application of paramagnetic contrast media, and the novel NMR spectroscopy as a method pointing into the future. All contributions discussing the clinical aspects have been written jointly by experts in orthopedics and radiology. (orig.) With 153 figs., 8 tabs [de

  16. Health-economic evaluation in implant trials: design considerations.

    Science.gov (United States)

    Alt, Volker; Pavlidis, Theodoros; Szalay, Gabor; Heiss, Christian; Schnettler, Reinhard

    2009-01-01

    In today's world, demonstration of the safety, efficacy, and quality of a new treatment strategy is no longer sufficient in many countries for market entry and reimbursement in the public healthcare system. This implies that new implants in orthopedic and orthopedic trauma surgery not only must be shown to lead to better medical outcome compared with the standard of care implant, but also must be shown to exhibit "good value" for the money for the public health-care system based on sound economic data from health-economic studies. The purpose of this article is to elucidate a framework for health-economic aspects alongside implant trials, with the assumption that the new implant is more costly but potentially better than the control implant. Cost-effectiveness, cost-utility, and cost-benefit studies are suitable for the assessment of the health-economic value of a new implant. The following criteria should be considered for a health-economic study design in the context with an implant: i) it should state medical benefits of the new implant compared with the control implant; ii) it should precise the type of health economic study; iii) it should define the methodological approach, perspective of the study, and types of costs; iv) if necessary, it should state discount costs and/benefits; and v) a sound sensitivity analysis should be included. Furthermore, close cooperation between researchers, clinicians, and health economists is essential.

  17. POROUS POLYMER IMPLANTS FOR REPAIR OF FULL-THICKNESS DEFECTS OF ARTICULAR-CARTILAGE - AN EXPERIMENTAL-STUDY IN RABBIT AND DOG

    NARCIS (Netherlands)

    JANSEN, HWB; VETH, RPH; NIELSEN, HKL; DEGROOT, JH; PENNINGS, AJ

    1992-01-01

    Full-thickness defects of articular cartilage were repaired by implantation of porous polymer implants in rabbits and dogs. The quality of the repair tissue was determined by collagen typing with antibodies. Implants with varying pore sizes and chemical composition were used. The effect of loading

  18. Tumor hepático experimental (VX-2 em coelho: implantação do modelo no Brasil Experimental liver tumor (VX-2 in rabbits: implantation of the model in Brazil

    Directory of Open Access Journals (Sweden)

    Rogério Saad Hossne

    2002-08-01

    Full Text Available Os estudos para a investigação de novas modalidades terapêuticas em biologia tumoral, deveriam passar por estudos experimentais prévios. Neste sentido dispõem-se hoje de uma grande variedade de modelos tumorais experimentais; em determinadas investigações faz-se necessária a adequação do modelo tumoral às necessidades biológicas, patológicas e experimentais dos estudos. Desta forma, em nosso serviço, buscávamos um modelo tumoral hepático para estudos experimentais que se adequasse às seguintes características: fácil manipulação, crescimento controlável, evolução e agressividade semelhantes aos seres humanos. Os dados da literatura nos levaram a busca do tumor hepático VX-2, em coelhos. Neste artigo discutimos as vantagens da utilização deste modelo experimental e a sua introdução em nosso país.Studies for investigation of new therapeutic modalities in tumoral biology should be based on previous experimental studies. Then, there are a great variety of tumoral experimental models today. Some investigations have been done necessary an adaptation of the tumoral model to the needing of the studies biological and pathological. So, in our laboratory, we looked for a tumoral hepatic model for experimental studies with the following characteristics: easy manipulation, control of growing, evolution and aggressiveness like to humans. Data of the literature took us the search of the hepatic tumor VX-2, in rabbits. In this article we discussed the advantages of use this experimental model and its introduction in our country. Experimental hepatic tumor (VX-2 in rabbit. Implantation of the model in Brazil.

  19. Osseointegration of zirconia implants: an SEM observation of the bone-implant interface.

    Science.gov (United States)

    Depprich, Rita; Zipprich, Holger; Ommerborn, Michelle; Mahn, Eduardo; Lammers, Lydia; Handschel, Jörg; Naujoks, Christian; Wiesmann, Hans-Peter; Kübler, Norbert R; Meyer, Ulrich

    2008-11-06

    The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Göttinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level.

  20. Orthopedic Health: Osteoarthritis— What You Should Know (quiz)

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Orthopedic Health Osteoarthritis— What You Should Know Past Issues / Spring 2009 ... Javascript on. How much do you know about osteoarthritis, its causes, and its therapies? Take this quiz ...

  1. Comparing consensus guidelines on thromboprophylaxis in orthopedic surgery

    NARCIS (Netherlands)

    Struijk-Mulder, M. C.; Ettema, H. B.; Verheyen, C. C.; Büller, H. R.

    2010-01-01

    BACKGROUND: Different guidelines exist regarding the prevention of venous thromboembolism (VTE) in orthopedic surgery. OBJECTIVES: We aimed to compare (inter)national guidelines and analyse differences. Methods: MEDLINE, the Cochrane Library and the internet were searched for guidelines on the

  2. Value of PCR in sonication fluid for the diagnosis of orthopedic hardware-associated infections: Has the molecular era arrived?

    Science.gov (United States)

    Renz, Nora; Cabric, Sabrina; Morgenstern, Christian; Schuetz, Michael A; Trampuz, Andrej

    2018-04-01

    Bone healing disturbance following fracture fixation represents a continuing challenge. We evaluated a novel fully automated polymerase chain reaction (PCR) assay using sonication fluid from retrieved orthopedic hardware to diagnose infection. In this prospective diagnostic cohort study, explanted orthopedic hardware materials from consecutive patients were investigated by sonication and the resulting sonication fluid was analyzed by culture (standard procedure) and multiplex PCR (investigational procedure). Hardware-associated infection was defined as visible purulence, presence of a sinus tract, implant on view, inflammation in peri-implant tissue or positive culture. McNemar's chi-squared test was used to compare the performance of diagnostic tests. For the clinical performance all pathogens were considered, whereas for analytical performance only microorganisms were considered for which primers are included in the PCR assay. Among 51 patients, hardware-associated infection was diagnosed in 38 cases (75%) and non-infectious causes in 13 patients (25%). The sensitivity for diagnosing infection was 66% for peri-implant tissue culture, 84% for sonication fluid culture, 71% (clinical performance) and 77% (analytical performance) for sonication fluid PCR, the specificity of all tests was >90%. The analytical sensitivity of PCR was higher for gram-negative bacilli (100%), coagulase-negative staphylococci (89%) and Staphylococcus aureus (75%) than for Cutibacterium (formerly Propionibacterium) acnes (57%), enterococci (50%) and Candida spp. (25%). The performance of sonication fluid PCR for diagnosis of orthopedic hardware-associated infection was comparable to culture tests. The additional advantage of PCR was short processing time (PCR has the potential to complement conventional cultures. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Monitoring the osseointegration process in porous Ti6Al4V implants produced by additive manufacturing: an experimental study in sheep.

    Science.gov (United States)

    Kayacan, Mehmet C; Baykal, Yakup B; Karaaslan, Tamer; Özsoy, Koray; Alaca, İlker; Duman, Burhan; Delikanlı, Yunus E

    2018-04-01

    This study investigated the design and osseointegration process of transitive porous implants that can be used in humans and all trabecular and compact bone structure animals. The aim was to find a way of forming a strong and durable tissue bond on the bone-implant interface. Massive and transitive porous implants were produced on a direct metal laser sintering machine, surgically implanted into the skulls of sheep and kept in place for 12 weeks. At the end of the 12-week period, the Massive and porous implants removed from the sheep were investigated by scanning electron microscopy (SEM) to monitor the osseointegration process. In the literature, each study has selected standard sizes for pore diameter in the structures they use. However, none of these involved transitional porous structures. In this study, as opposed to standard pores, there were spherical or elliptical pores at the micro level, development channels and an inner region. Bone cells developed in the inner region. Transitive pores grown gradually in accordance with the natural structure of the bone were modeled in the inner region for cells to develop. Due to this structure, a strong and durable tissue bond could be formed at the bone-implant interface. Osseointegration processes of Massive vs. porous implants were compared. It was observed that cells were concentrated on the surface of Massive implants. Therefore, osseointegration between implant and bone was less than that of porous implants. In transitive porous implants, as opposed to Massive implants, an outer region was formed in the bone-implant interface that allowed tissue development.

  4. Pediatric orthopedic surgery in humanitarian aid.

    Science.gov (United States)

    Sales de Gauzy, J; Trinchero, J-F; Jouve, J-L

    2017-02-01

    Pediatric orthopedic surgery in humanitarian aid is conducted mainly in cooperation with emerging countries. Each mission is different, and depends on numerous parameters such as the country, the frequency of such missions, the pathologies encountered, the local structure and team, and the non-governmental organization (NGO) involved. Pathologies vary in etiology (tuberculosis, poliomyelitis) and severity. Each mission requires the presence of an experienced surgeon. Working conditions are often rudimentary. Surgical indications should be restricted to procedures that are going to be effective, with minimal postoperative complications, without any surgical "acrobatics". Teaching should be in association with the local university, and adapted to local needs. Mission objectives need to be realistic. Surgical indications should be adapted to local conditions, and the surgeon needs to be able to say "no" to procedures involving undue risk. The surgeon on mission should cooperate with local teams and be able to adapt to unusual situations. Assessment of results is essential to improving efficacy and evaluating the success of the mission. Copyright © 2016. Published by Elsevier Masson SAS.

  5. Orthopedic rehabilitation using the "Rutgers ankle" interface.

    Science.gov (United States)

    Girone, M; Burdea, G; Bouzit, M; Popescu, V; Deutsch, J E

    2000-01-01

    A novel ankle rehabilitation device is being developed for home use, allowing remote monitoring by therapists. The system will allow patients to perform a variety of exercises while interacting with a virtual environment (VE). These game-like VEs created with WorldToolKit run on a host PC that controls the movement and output forces of the device via an RS232 connection. Patients will develop strength, flexibility, coordination, and balance as they interact with the VEs. The device will also perform diagnostic functions, measuring the ankle's range of motion, force exertion capabilities and coordination. The host PC transparently records patient progress for remote evaluation by therapists via our existing telerehabilitation system. The "Rutgers Ankle" Orthopedic Rehabilitation Interface uses double-acting pneumatic cylinders, linear potentiometers, and a 6 degree-of-freedom (DOF) force sensor. The controller contains a Pentium single-board computer and pneumatic control valves. Based on the Stewart platform, the device can move and supply forces and torques in 6 DOFs. A proof-of-concept trial conducted at the University of Medicine and Dentistry of New Jersey (UMDNJ) provided therapist and patient feedback. The system measured the range of motion and maximum force output of a group of four patients (male and female). Future medical trials are required to establish clinical efficacy in rehabilitation.

  6. Physician-Hospital Alignment in Orthopedic Surgery.

    Science.gov (United States)

    Bushnell, Brandon D

    2015-09-01

    The concept of "alignment" between physicians and hospitals is a popular buzzword in the age of health care reform. Despite their often tumultuous histories, physicians and hospitals find themselves under increasing pressures to work together toward common goals. However, effective alignment is more than just simple cooperation between parties. The process of achieving alignment does not have simple, universal steps. Alignment will differ based on individual situational factors and the type of specialty involved. Ultimately, however, there are principles that underlie the concept of alignment and should be a part of any physician-hospital alignment efforts. In orthopedic surgery, alignment involves the clinical, administrative, financial, and even personal aspects of a surgeon's practice. It must be based on the principles of financial interest, clinical authority, administrative participation, transparency, focus on the patient, and mutual necessity. Alignment can take on various forms as well, with popular models consisting of shared governance and comanagement, gainsharing, bundled payments, accountable care organizations, and other methods. As regulatory and financial pressures continue to motivate physicians and hospitals to develop alignment relationships, new and innovative methods of alignment will also appear. Existing models will mature and evolve, with individual variability based on local factors. However, certain trends seem to be appearing as time progresses and alignment relationships deepen, including regional and national collaboration, population management, and changes in the legal system. This article explores the history, principles, and specific methods of physician-hospital alignment and its critical importance for the future of health care delivery. Copyright 2015, SLACK Incorporated.

  7. Regional anesthesia techniques for ambulatory orthopedic surgery.

    LENUS (Irish Health Repository)

    O'Donnell, Brian D

    2012-02-03

    PURPOSE OF REVIEW: The purpose of this review is to present advances in the use of regional anesthetic techniques in ambulatory orthopedic surgery. New findings regarding the use of both neuraxial anesthesia and peripheral nerve block are discussed. RECENT FINDINGS: Neuraxial anesthesia: The use of short-acting local anesthetic agents such as mepivacaine, 2-chloroprocaine, and articaine permits rapid onset intrathecal anesthesia with early recovery profiles. Advantages and limitations of these agents are discussed.Peripheral nerve block: Peripheral nerve blocks in limb surgery have the potential to transform this patient cohort into a truly ambulatory, self-caring group. Recent trends and evidence regarding the benefits of regional anesthesia techniques are presented.Continuous perineural catheters permit extension of improved perioperative analgesia into the ambulatory home setting. The role and reported safety of continuous catheters are discussed. SUMMARY: In summary, shorter acting, neuraxial, local anesthetic agents, specific to the expected duration of surgery, may provide superior recovery profiles in the ambulatory setting. A trend towards more peripheral and selective nerve blocks exists. The infrapatellar block is a promising technique to provide analgesia following knee arthroscopy. Improved analgesia seen in the perioperative period can be safely and effectively extended to the postoperative period with the use of perineural catheters.

  8. Our experience with orthopedic surgery in hemophiliacs

    Directory of Open Access Journals (Sweden)

    Poenaru Dan V.

    2006-01-01

    Full Text Available Introduction: Patients having severe hemophilia (levels of deficient factor below 1% frequently suffer from disabling chronic arthropathy. An adequate substitution treatment using the coagulation factor VIII or IX concentrates renders an elective surgery feasible. Objective: The objective of the study was to check the results of different surgical procedures in the treatment of hemophilic arthropathies, and to propose the best protocol of their treatment. Methods: This is a retrospective study on 26 hemophilic patients operated in the Orthopedics and Trauma Clinic II, Timisoara, from 2002 to 2005. Elective surgical procedures were mainly performed in the knee (21 arthroscopic procedures, 1 open arthrodesis, elbow (2 open synovectomies, 2 radial head excisions, ankle (1 arthroscopic synovectomy and debridement and thigh (1 giant pseudo tumor excision, other minor procedures. The results after operations on moderate and severe chronic knee, elbow and ankle arthropathy were evaluated, with approximately 24-month follow-up period. Results: Arthroscopic procedures (22 yielded good and satisfactory results with significant improvement according to the evaluation criteria recommended by the World Hemophilia Federation (Gilbert clinical score, Pettersson radiological score, NUSS MRI score. Conclusion: Mini-invasive elective surgery in moderate to severe chronic arthropathy produces good results when performed in a specialized center and with multi-disciplinary approach.

  9. 3D-printed patient-specific applications in orthopedics

    OpenAIRE

    Wong KC

    2016-01-01

    Kwok Chuen Wong Department of Orthopedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong Abstract: With advances in both medical imaging and computer programming, two-dimensional axial images can be processed into other reformatted views (sagittal and coronal) and three-dimensional (3D) virtual models that represent a patients’ own anatomy. This processed digital information can be analyzed in detail by orthopedic surgeons to perform p...

  10. How Useful are Orthopedic Surgery Residency Web Pages?

    Science.gov (United States)

    Oladeji, Lasun O; Yu, Jonathan C; Oladeji, Afolayan K; Ponce, Brent A

    2015-01-01

    Medical students interested in orthopedic surgery residency positions frequently use the Internet as a modality to gather information about individual residency programs. Students often invest a painstaking amount of time and effort in determining programs that they are interested in, and the Internet is central to this process. Numerous studies have concluded that program websites are a valuable resource for residency and fellowship applicants. The purpose of the present study was to provide an update on the web pages of academic orthopedic surgery departments in the United States and to rate their utility in providing information on quality of education, faculty and resident information, environment, and applicant information. We reviewed existing websites for the 156 departments or divisions of orthopedic surgery that are currently accredited for resident education by the Accreditation Council for Graduate Medical Education. Each website was assessed for quality of information regarding quality of education, faculty and resident information, environment, and applicant information. We noted that 152 of the 156 departments (97%) had functioning websites that could be accessed. There was high variability regarding the comprehensiveness of orthopedic residency websites. Most of the orthopedic websites provided information on conference, didactics, and resident rotations. Less than 50% of programs provided information on resident call schedules, resident or faculty research and publications, resident hometowns, or resident salary. There is a lack of consistency regarding the content presented on orthopedic residency websites. As the competition for orthopedic websites continues to increase, applicants flock to the Internet to learn more about orthopedic websites in greater number. A well-constructed website has the potential to increase the caliber of students applying to a said program. Copyright © 2015 Association of Program Directors in Surgery. Published by

  11. Synergistic effects of bisphosphonate and calcium phosphate nanoparticles on peri-implant bone responses in osteoporotic rats

    NARCIS (Netherlands)

    Alghamdi, H.S.A.; Bosco, R.; Both, S.K.; Iafisco, M.; Leeuwenburgh, S.C.G.; Jansen, J.A.; Beucken, J.J.J.P van den

    2014-01-01

    The prevalence of osteoporosis will increase within the next decades due to the aging world population, which can affect the bone healing response to dental and orthopedic implants. Consequently, local drug targeting of peri-implant bone has been proposed as a strategy for the enhancement of

  12. Orthopedic surgery-related benign uptake on FDG-PET. Case examples and pitfalls

    International Nuclear Information System (INIS)

    Liu, Y.

    2009-01-01

    Orthopedic surgical procedures often create some special postoperative complications, which may demonstrate abnormally increased or focal uptake for an extended period of time on fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT images. The distinction of normal from pathologic, benign from malignant uptake is very important to minimize the number of false positive results. To date, very little data have been published regarding surgical-related benign musculoskeletal uptake on PET-CT imaging. In this paper, we present to the readers some case examples of FDG PET-CT imaging for postoperative fracture, infection or osteomyelitis, metallic implants, aggressive bone edge, heterotopic ossification, granuloma and neuroma. We also discuss potential pitfalls to recognize these orthopedic surgery-related complications and identify benign nature of increased FDG uptake. In all cases, the patient's medical and surgical history would be of paramount importance to the radiologists/nuclear medicine physicians who interprets the scan. It is also crucial to carefully correlate FDG uptake with the anatomy on the co-registered CT images in all transaxial, coronal and sagittal views in order to identify the location and pattern of uptake. (author)

  13. Osteoblast adhesion on novel machinable calcium phosphate/lanthanum phosphate composites for orthopedic applications.

    Science.gov (United States)

    Ergun, Celaletdin; Liu, Huinan; Webster, Thomas J

    2009-06-01

    Lanthanum phosphate (LaPO(4), LP) was combined with either hydroxyapatite (HA) or tricalcium phosphate (TCP) to form novel composites for orthopedic applications. In this study, these composites were prepared by wet chemistry synthesis and subsequent powder mixing. These HA/LP and TCP/LP composites were characterized in terms of phase stability and microstructure evolution during sintering using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Their machinability was evaluated using a direct drilling test. For HA/LP composites, LP reacted with HA during sintering and formed a new phase, Ca(8)La(2)(PO(4))(6)O(2), as a reaction by-product. However, TCP/LP composites showed phase stability and the formation of a weak interface between TCP and LP machinability when sintered at 1100 degrees C, which is crucial for achieving desirable properties. Thus, these novel TCP/LP composites fulfilled the requirements for machinability, a key consideration for manufacturing orthopedic implants. Moreover, the biocompatibility of these novel LP composites was studied, for the first time, in this paper. In vitro cell culture tests demonstrated that the LP and its composites supported osteoblast (bone-forming cell) adhesion similar to natural bioceramics (such as HA and TCP). In conclusion, these novel LP composites should be further studied and developed for more effectively treating bone related diseases or injuries. 2008 Wiley Periodicals, Inc.

  14. Implante de tubo valvulado bioprótese "stentless" em posição aórtica: estudo experimental em ovinos A juvenile sheep model for the stentless bioprostheses implanted as aortic root replacements

    Directory of Open Access Journals (Sweden)

    Paulo César SANTOS

    2002-03-01

    Full Text Available INTRODUÇÃO: O tratamento das lesões valvares representa um grande desafio dentro da cirurgia cardiovascular, pois, até os dias atuais, não temos um substituto ideal para as valvas do coração. As próteses atualmente disponíveis apresentam vantagens e desvantagens; as mecânicas exigem anticoagulação definitiva e as biológicas apresentam baixa durabilidade. Para se chegar a um substituto ideal, são necessárias várias fases, desde a escolha e o preparo do material até o implante em animal de grande porte. Esta última é muito importante, pois a escolha do animal deve ser criteriosa. Ovinos juvenís são animais dóceis de fácil manipulação e suas características anatômicas e biológicas se assemelham muito ao que ocorre com o ser humano e as próteses "stentless" são substitutos mais próximos dos homoenxertos. MATERIAL E MÉTODO: Foram operados 30 ovinos juvenís com idade variando de 4,4 a 6,3 meses, peso de 25 a 37 kg, sendo 28 machos. Todos os animais foram submetidos a circulação extracorpórea para implante de bioprótese "stentless" montada em tubo de aorta porcina, com reimplante de artérias coronárias. A operação foi realizada com hipotermia moderada e cardioplegia gelada. O período de seguimento foi de 30 dias e, ao final, realizado ecocardiograma. RESULTADOS: Houve 8 (26,6% óbitos no intra-operatório e 6 (27,7% óbitos no seguimento. O tempo médio de CEC foi de 98 min. Foi realizado ecocardiograma em 16 animais e em nenhum caso foram vistos sinais de endocardite ou outras alterações; a fração média de ejeção foi de 74%. CONCLUSÃO: Este modelo experimental utilizando ovinos para o estudo de biopróteses "stentless" em posição aórtica mostrou-se bem reprodutível e a performance do enxerto bastante factível de ser avaliada, pois ovinos são animais dóceis e de fácil manipulação no seguimento tardio.INTRODUCTION: Often, studies on aortic prosthetic valves analyze their performance not at the

  15. Orthopedic injuries associated with backyard trampoline use in children.

    Science.gov (United States)

    Black, G Brian; Amadeo, Ryan

    2003-06-01

    Trampolining on an outdoor oval or circular trampoline is a popular activity for children but is associated with a number of orthopedic injuries, especially in children between the ages of 5 and 15 years. In this paper we review the orthopedic injuries in children associated with backyard trampoline use, through our experience with a series of children admitted to the Winnipeg Children's Hospital, the only tertiary care pediatric centre in Manitoba. We reviewed the charts, x-ray films and operative reports for 80 children under 16 years old (mean 9 yr, with 14 [18%] children between 2 and 4 yr) with an orthopedic injury sustained when using a trampoline in the backyard. We noted the mechanism of injury and type and severity of orthopedic injury sustained. Fifty-two (65%) children were injured on the trampoline mat, and 24 (30%) were injured when they were ejected from the trampoline. Sixty (75%) children sustained a fracture or fracture-dislocation. Forty-eight (80%) orthopedic injuries occurred in the upper extremity. No child died as a result of a trampoline injury. The use of the "backyard" trampoline by young children can cause significant orthopedic injury.

  16. Chemoprophylaxis in cardiac and orthopedic surgery: comparison of cephalothin and cephapirin.

    Science.gov (United States)

    Bryant, R E; Hartstein, A I; Starr, A; Beals, R K

    1982-09-01

    In a retrospective sequential study we determined the rate of infection occurring despite cephalothin or cephapirin chemoprophylaxis in orthopedic and cardiac surgery done from 1973 to 1977. The incidence of infection after prosthetic hip placement or open reduction of hip fracture was 3.4% and 1.0% in patients receiving cephalothin or cephapirin, respectively. The infection rate after prosthetic heart valve implantation was 3.5% in those receiving cephalothin and 1.6% in those receiving cephapirin. There was no significant difference in infection rate, duration of fever greater than or equal to 38.0 C, or length of postoperative hospitalization. The efficacy of selected antistaphylococcal antibiotics in preventing colonization of human fibrin clots by staphylococci was studied. Although cephapirin was effective at lower concentration, the activity of cephalothin and cephapirin was comparable. Cephalothin and cephapirin have equivalent chemoprophylactic activity by clinical and microbiological criteria, permitting cost to be used as a basis for choosing between these antibiotics.

  17. Polymers as Carriers of Gentamicin in Traumatology and Orthopedic Surgery - Current State Of Knowledge.

    Science.gov (United States)

    Witkowski, Jarosław; Wnukiewicz, Witold; Reichert, Paweł

    2016-01-01

    Osteomyelitis in patients undergoing surgery because of injuries and diseases of the musculoskeletal system is a serious clinical, economic and social problem. It is one of the greatest therapeutic challenges in traumatology and orthopedic surgery. To achieve the best results in the treatment of osteomyelitis, surgical debridement and intravenous antibiotic therapy is supported by local antibiotic delivery. Many different substances can be used as drug carriers. In this study we present and compare some polymers used as carriers of gentamicin. Some of them, such as poly(methyl methacrylate), are well known and have been used for 30 years, and others, such as polycaprolactone, polyacrylic acid, polyanhydrides, poly-trimethylene carbonate, polylactide, polyglycolide and poly(trimethylene carbonate), are perspectives for the future. In this study, we have tried to briefly present all of these polymers and compare some of their features. We have concentrated on the pharmacokinetics and bioactivity of such implants, which are important aspects for their potential practical use.

  18. In-111-labeled leukocyte scintigraphy in suspected orthopedic prosthesis infection: comparison with other imaging modalities

    International Nuclear Information System (INIS)

    Magnuson, J.E.; Brown, M.L.; Hauser, M.F.; Berquist, T.H.; Fitzgerald, R.H. Jr.; Klee, G.G.

    1988-01-01

    When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively

  19. Damping Factor as a Diagnostic Parameter for Assessment of Osseointegration during the Dental Implant Healing Process: An Experimental Study in Rabbits.

    Science.gov (United States)

    Feng, Sheng-Wei; Ho, Kuo-Ning; Chan, Ya-Hui; Chang, Kai-Jung; Lai, Wei-Yi; Huang, Haw-Ming

    2016-12-01

    The purpose of this study was to evaluate the possibility of using damping factor (DF) analysis to provide additional information on osseointegration of dental implants during the healing period. A total of 30 dental implants were installed in the bilateral femoral condyles of 15 rabbits. A DF analyzer detected with an impulse-forced vibration method and a commercialized dental implant stability analyzer based on resonance frequency (RF) analysis were used to measure the implant stability immediately after implant placement and 1, 2, 4, and 8 weeks post-surgically. Results of DF and RF analyses at different time points were compared with the corresponding osseointegration performance of dental implants via micro-computed tomography (micro-CT), histological and histomorphometrical analysis. The DF values revealed a decrease with time and reached 0.062 ± 0.007 at 8 weeks after implantation, which is almost 50% lower than the initial value. Moreover, highly significant correlations between DF values and bone volume densities (R 2  = 0.9797) and percentages of bone-to-implant contact measured at trabecular bone area (R 2  = 0.9773) were also observed. These results suggested that DF analysis combined with RF analysis results in a more sensitive assessment of changes in the dental implant/bone complex during the healing period than RF analysis alone.

  20. Cochlear Implants

    Science.gov (United States)

    ... implant, including: • How long a person has been deaf, •The number of surviving auditory nerve fibers, and • ... Implant, Severe Sensoryneurial Hearing Loss Get Involved Professional Development Practice Management ENT Careers Marketplace Privacy Policy Terms ...

  1. Outpatient parenteral antimicrobial therapy for orthopedic infections – a successful public healthcare experience in Brazil

    Directory of Open Access Journals (Sweden)

    Priscila Rosalba Oliveira

    2016-05-01

    Full Text Available Treatment of orthopedic infections usually requires prolonged antimicrobial therapy, ranging from 14 days up to 6 months. Nowadays, rising levels of antimicrobial resistance demands parenteral therapy for many patients. Outpatient parenteral antimicrobial therapy (OPAT is a modality that allows treatment out of hospital in these situations. In Brazil, where a public universal healthcare system allows full coverage for all citizens, implantation and dissemination of OPAT programs would be beneficial for patients and for the system, because it would allow a better allocation of health resources. The Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina da USP (IOT started, in July 2013, a partnership with municipal health authorities in Sao Paulo, Brazil, in order to initiate an OPAT program in which patients discharged from that hospital would be able to continue antimicrobial therapy at primary care facilities. When necessary, patients could also receive their therapy at the day-hospital located at IOT. Primary care nursing and physician staff were trained about antimicrobial infusion and peripherally inserted central catheter manipulation. An OPAT specific antimicrobial protocol was designed and a special reference and counter-reference organized. As a result, 450 primary healthcare professionals were trained. In the first year of this program, 116 patients were discharged for OPAT. Chronic and acute osteomyelitis were most frequent diagnosis. Teicoplanin, ertapenem and tigecycline were the most used drugs. Duration of treatment varied from 10 to 180 days (average 101, median 42. Total sum of days in OPAT regimen was 11,698. Only 3 patients presented adverse effects. Partnership between services of different levels of complexity allowed implantation of a safe and effective public healthcare OPAT program for treatment of orthopedic infections. This program can serve as a model for developing similar strategies

  2. The Quality of Cost-Utility Analyses in Orthopedic Trauma.

    Science.gov (United States)

    Nwachukwu, Benedict U; Schairer, William W; O'Dea, Evan; McCormick, Frank; Lane, Joseph M

    2015-08-01

    As health care in the United States transitions toward a value-based model, there is increasing interest in applying cost-effectiveness analysis within orthopedic surgery. Orthopedic trauma care has traditionally underemphasized economic analysis. The goals of this review were to identify US-based cost-utility analysis in orthopedic trauma, to assess the quality of the available evidence, and to identify cost-effective strategies within orthopedic trauma. Based on a review of 971 abstracts, 8 US-based cost-utility analyses evaluating operative strategies in orthopedic trauma were identified. Study findings were recorded, and the Quality of Health Economic Studies (QHES) instrument was used to grade the overall quality. Of the 8 studies included in this review, 4 studies evaluated hip and femur fractures, 3 studies analyzed upper extremity fractures, and 1 study assessed open tibial fracture management. Cost-effective interventions identified in this review include total hip arthroplasty (over hemiarthroplasty) for femoral neck fractures in the active elderly, open reduction and internal fixation (over nonoperative management) for distal radius and scaphoid fractures, limb salvage (over amputation) for complex open tibial fractures, and systems-based interventions to prevent delay in hip fracture surgery. The mean QHES score of the studies was 79.25 (range, 67-89). Overall, there is a paucity of cost-utility analyses in orthopedic trauma; however, the available evidence suggests that certain operative interventions can be cost-effective. The quality of these studies, however, is fair, based on QHES grading. More attention should be paid to evaluating the cost-effectiveness of operative intervention in orthopedic trauma. Copyright 2015, SLACK Incorporated.

  3. Recent advances in standing equine orthopedic surgery.

    Science.gov (United States)

    O'Brien, Thomas; Hunt, Robert J

    2014-04-01

    In all surgeries with the patient standing under chemical and physical restraint, patient compliance is of the utmost importance. All fractures of the third metacarpal or metatarsal condyles and sagittal fracture of the first phalanx are not amenable to internal fixation with the horse standing, and young unhandled horses may not have a suitable disposition for standing surgical treatment of septic pedal osteitis, or implantation and removal of transphyseal screws. Previous operator experience in performing the procedure or technique under general anesthesia is beneficial. Appreciation of appropriate topographic anatomic landmarks is important, and intraoperative radiographic control is useful. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Combined stent implantation and embolization with liquid 2-polyhydroxyethyl methacrylate for treatment of experimental canine wide-necked aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Klisch, J.; Zitt, J.; Schumacher, M. [Section of Neuroradiology, University of Freiburg (Germany); Schellhammer, F. [Department of Radiology, University of Cologne, Cologne (Germany); Scheufler, K.M. [Department of Neurosurgery, University of Freiburg (Germany); Pagenstecher, A. [Department of Neuropathology, University of Freiburg, Freiburg (Germany); Nagursky, H. [Department of Oral and Maxillofacial Surgery, University of Freiburg, Freiburg (Germany)

    2002-06-01

    The purpose of the study was the evaluation of 2-polyhydroxyethyl methacrylate (2-P-HEMA) for endovascular liquid embolization of experimental side-wall aneurysms following stent protection in a canine model. The swelling behaviour and polymerization characteristics of 2-P-HEMA in different solutions were investigated in vitro. Different methods for applications were tested in a latex aneurysm model under pulsatile flow conditions. Twenty broad-based carotid side-wall aneurysms were microsurgically produced in five dogs. Four weeks after surgery self-expandable nitinol stents were placed, covering the orifice of the aneurysms. 2-P-HEMA was injected via a microcatheter, which was positioned through the meshwork of the stent. Control angiography was performed immediately after treatment and after 1, 6 and 9 months. In-vivo stent placement succeeded in all but one case. Two aneurysms occluded spontaneously after stent placement. Combined embolization of 17 aneurysms using a stent and 2-P-HEMA was performed. Eleven aneurysms could be primarily completely occluded (65%). A small remaining neck was evident in six aneurysms. Efflux of 2-P-HEMA during the process of embolization was observed in seven aneurysms, due to an excess volume of 2-P-HEMA. The excessive 2-P-HEMA led to significant vessel stenosis in two cases. Two carotid arteries (three treated aneurysms) occluded after 1 month, due to insufficient anticoagulation management. Histological examination of embolized aneurysms revealed no foreign-body or inflammatory reaction. A smooth neo-intimal layer covered the stented vessel segment. Liquid embolization of side-wall aneurysms with 2-P-HEMA is technically feasible. Embolotherapy of aneurysms with liquid agents still has the risk that embolic material will exit even when it is stent-protected. To avoid this problem, stents with smaller strut diameter and/or additional balloon-protection are required. The inert 2-P-HEMA seems to be a promising agent for combining

  5. Chemical and structural analysis of the bone-implant interface by TOF-SIMS, SEM, FIB and TEM: Experimental study in animal

    International Nuclear Information System (INIS)

    Palmquist, Anders; Emanuelsson, Lena; Sjövall, Peter

    2012-01-01

    Although bone-anchored implants are widely used in reconstructive medicine, the mechanism of osseointegration is still not fully understood. Novel analytical tools are needed to further understand this process, where both the chemical and structural aspects of the bone-implant interface are important. The aim of this study was to evaluate the advantages of combining time-of-flight secondary ion mass spectroscopy (TOF-SIMS) with optical (LM), scanning (SEM) and transmission electron microscopy (TEM) techniques for studying the bone-implant interface of bone-anchored implants. Laser-modified titanium implants with surrounded bone retrieved after 8 weeks healing in rabbit were dehydrated and resin embedded. Three types of sample preparation were studied to evaluate the information gained by combining TOF-SIMS, SEM, FIB and TEM. The results show that imaging TOF-SIMS can provide detailed chemical information, which in combination with structural information from microscopy methods provide a more complete characterization of anatomical structures at the bone-implant interface. By investigating various sample preparation techniques, it is shown that grinded cross section samples can be used for chemical imaging using TOF-SIMS, if careful consideration of potential preparation artifacts is taken into account. TOF-SIMS analysis of FIB-prepared bone/implant cross section samples show distinct areas corresponding to bone tissue and implant with a sharp interface, although without chemical information about the organic components.

  6. Safety and Biocompatibility of a New High-Density Polyethylene-Based Spherical Integrated Porous Orbital Implant: An Experimental Study in Rabbits

    Directory of Open Access Journals (Sweden)

    Ivan Fernandez-Bueno

    2015-01-01

    Full Text Available Purpose. To evaluate clinically and histologically the safety and biocompatibility of a new HDPE-based spherical porous orbital implants in rabbits. Methods. MEDPOR (Porex Surgical, Inc., Fairburn, GA, USA, OCULFIT I, and OCULFIT II (AJL Ophthalmic S.A., Vitoria, Spain implants were implanted in eviscerated rabbis. Animals were randomly divided into 6 groups (n=4 each according to the 3 implant materials tested and 2 follow-up times of 90 or 180 days. Signs of regional pain and presence of eyelid swelling, conjunctival hyperemia, and amount of exudate were semiquantitatively evaluated. After animals sacrifice, the implants and surrounding ocular tissues were processed for histological staining and polarized light evaluation. Statistical study was performed by ANOVA and Kaplan-Meier analysis. Results. No statistically significant differences in regional pain, eyelid swelling, or conjunctival hyperemia were shown between implants and/or time points evaluated. However, amount of exudate differed, with OCULFIT I causing the smallest amount. No remarkable clinical complications were observed. Histological findings were similar in all three types of implants and agree with minor inflammatory response. Conclusions. OCULFIT ophthalmic tolerance and biocompatibility in rabbits were comparable to the clinically used MEDPOR. Clinical studies are needed to determine if OCULFIT is superior to the orbital implants commercially available.

  7. Safety and Biocompatibility of a New High-Density Polyethylene-Based Spherical Integrated Porous Orbital Implant: An Experimental Study in Rabbits

    Science.gov (United States)

    Fernandez-Bueno, Ivan; Di Lauro, Salvatore; Alvarez, Ivan; Lopez, Jose Carlos; Garcia-Gutierrez, Maria Teresa; Fernandez, Itziar; Larra, Eva; Pastor, Jose Carlos

    2015-01-01

    Purpose. To evaluate clinically and histologically the safety and biocompatibility of a new HDPE-based spherical porous orbital implants in rabbits. Methods. MEDPOR (Porex Surgical, Inc., Fairburn, GA, USA), OCULFIT I, and OCULFIT II (AJL Ophthalmic S.A., Vitoria, Spain) implants were implanted in eviscerated rabbis. Animals were randomly divided into 6 groups (n = 4 each) according to the 3 implant materials tested and 2 follow-up times of 90 or 180 days. Signs of regional pain and presence of eyelid swelling, conjunctival hyperemia, and amount of exudate were semiquantitatively evaluated. After animals sacrifice, the implants and surrounding ocular tissues were processed for histological staining and polarized light evaluation. Statistical study was performed by ANOVA and Kaplan-Meier analysis. Results. No statistically significant differences in regional pain, eyelid swelling, or conjunctival hyperemia were shown between implants and/or time points evaluated. However, amount of exudate differed, with OCULFIT I causing the smallest amount. No remarkable clinical complications were observed. Histological findings were similar in all three types of implants and agree with minor inflammatory response. Conclusions. OCULFIT ophthalmic tolerance and biocompatibility in rabbits were comparable to the clinically used MEDPOR. Clinical studies are needed to determine if OCULFIT is superior to the orbital implants commercially available. PMID:26689343

  8. The Synergistic Effect of Leukocyte Platelet-Rich Fibrin and Micrometer/Nanometer Surface Texturing on Bone Healing around Immediately Placed Implants: An Experimental Study in Dogs

    Science.gov (United States)

    Neiva, Rodrigo F.; Gil, Luiz Fernando; Tovar, Nick; Janal, Malvin N.; Marao, Heloisa Fonseca; Pinto, Nelson; Coelho, Paulo G.

    2016-01-01

    Aims. This study evaluated the effects of L-PRF presence and implant surface texture on bone healing around immediately placed implants. Methods. The first mandibular molars of 8 beagle dogs were bilaterally extracted, and implants (Blossom™, Intra-Lock International, Boca Raton, FL) were placed in the mesial or distal extraction sockets in an interpolated fashion per animal. Two implant surfaces were distributed per sockets: (1) dual acid-etched (DAE, micrometer scale textured) and (2) micrometer/nanometer scale textured (Ossean™ surface). L-PRF (Intraspin system, Intra-Lock International) was placed in a split-mouth design to fill the macrogap between implant and socket walls on one side of the mandible. The contralateral side received implants without L-PRF. A mixed-model ANOVA (at α = 0.05) evaluated the effect of implant surface, presence of L-PRF, and socket position (mesial or distal), individually or in combination on bone area fraction occupancy (BAFO). Results. BAFO values were significantly higher for the Ossean relative to the DAE surface on the larger mesial socket. The presence of L-PRF resulted in higher BAFO. The Ossean surface and L-PRF presence resulted in significantly higher BAFO. Conclusion. L-PRF and the micro-/nanometer scale textured surface resulted in increased bone formation around immediately placed implants. PMID:28042577

  9. The Synergistic Effect of Leukocyte Platelet-Rich Fibrin and Micrometer/Nanometer Surface Texturing on Bone Healing around Immediately Placed Implants: An Experimental Study in Dogs

    Directory of Open Access Journals (Sweden)

    Rodrigo F. Neiva

    2016-01-01

    Full Text Available Aims. This study evaluated the effects of L-PRF presence and implant surface texture on bone healing around immediately placed implants. Methods. The first mandibular molars of 8 beagle dogs were bilaterally extracted, and implants (Blossom™, Intra-Lock International, Boca Raton, FL were placed in the mesial or distal extraction sockets in an interpolated fashion per animal. Two implant surfaces were distributed per sockets: (1 dual acid-etched (DAE, micrometer scale textured and (2 micrometer/nanometer scale textured (Ossean™ surface. L-PRF (Intraspin system, Intra-Lock International was placed in a split-mouth design to fill the macrogap between implant and socket walls on one side of the mandible. The contralateral side received implants without L-PRF. A mixed-model ANOVA (at α=0.05 evaluated the effect of implant surface, presence of L-PRF, and socket position (mesial or distal, individually or in combination on bone area fraction occupancy (BAFO. Results. BAFO values were significantly higher for the Ossean relative to the DAE surface on the larger mesial socket. The presence of L-PRF resulted in higher BAFO. The Ossean surface and L-PRF presence resulted in significantly higher BAFO. Conclusion. L-PRF and the micro-/nanometer scale textured surface resulted in increased bone formation around immediately placed implants.

  10. Serious Leisure and People with Orthopedic Impairment: Benefits and Constraints

    Directory of Open Access Journals (Sweden)

    Manolya AKSATAN

    2017-12-01

    Full Text Available There are many people around the world who have different types of disabilities. Understanding their needs is the first step of developing policies to increase their quality of life and satisfaction. Leisure is an essential need of disabled people and it plays an important role in disabled people’s lives. The purpose of this study is to gain a deep understanding on the serious leisure activities of people with orthopedic impairment, and also both benefits and constraints involved with serious leisure. Therefore, semi-structured in-depth interviews were conducted with 17 people who have orthopedic impairment. The data collected through interviews was analyzed by using a coding process. Findings of the study indicate that people with orthopedic impairment pursue many leisure activities. The research revealed that the participants were aware of significant individual and community benefits of serious leisure activities. Although the benefits of leisure for private and community life are obvious for people with orthopedic impairment, it is not always easy for them to pursue serious leisure activities. Disabled people recognize that there are many constraints involved with serious leisure. Based on the findings, these constraints are explained as psychological factors, family support, level of orthopedic impairment, community awareness and environmental factors, work and income.

  11. Patient Attitudes Toward Orthopedic Surgeon Ownership of Related Ancillary Businesses.

    Science.gov (United States)

    Yi, Paul H; Cross, Michael B; Johnson, Staci R; Rasinski, Kenneth A; Nunley, Ryan M; Della Valle, Craig J

    2016-08-01

    Physician ownership of businesses related to orthopedic surgery, such as surgery centers, has been criticized as potentially leading to misuse of health care resources. The purpose of this study was to determine patients' attitudes toward surgeon ownership of orthopedic-related businesses. We surveyed 280 consecutive patients at 2 centers regarding their attitudes toward surgeon ownership of orthopedic-related businesses using an anonymous questionnaire. Three surgeon ownership scenarios were presented: (1) owning a surgery center, (2) physical therapy (PT), and (3) imaging facilities (eg, Magnetic Resonance Imaging scanner). Two hundred fourteen patients (76%) completed the questionnaire. The majority agreed that it is ethical for a surgeon to own a surgery center (73%), PT practice (77%), or imaging facility (77%). Most (>67%) indicated that their surgeon owning such a business would have no effect on the trust they have in their surgeon. Although >70% agreed that a surgeon in all 3 scenarios would make the same treatment decisions, many agreed that such surgeons might perform more surgery (47%), refer more patients to PT (61%), or order more imaging (58%). Patients favored surgeon autonomy, however, believing that surgeons should be allowed to own such businesses (78%). Eighty-five percent agreed that patients should be informed if their surgeon owns an orthopedic-related business. Although patients express concern over and desire disclosure of surgeon ownership of orthopedic-related businesses, the majority believes that it is an ethical practice and feel comfortable receiving care at such a facility. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Does thromboprophylaxis prevent venous thromboembolism after major orthopedic surgery?

    Directory of Open Access Journals (Sweden)

    Evrim Eylem Akpinar

    2013-06-01

    Full Text Available OBJECTIVE: Pulmonary embolism (PE is an important complication of major orthopedic surgery. The aim of this study was to evaluate the incidence of venous thromboembolism (VTE and factors influencing the development of VTE in patients undergoing major orthopedic surgery in a university hospital. METHODS: Patients who underwent major orthopedic surgery (hip arthroplasty, knee arthroplasty, or femur fracture repair between February of 2006 and June of 2012 were retrospectively included in the study. The incidences of PE and deep vein thrombosis (DVT were evaluated, as were the factors influencing their development, such as type of operation, age, and comorbidities. RESULTS: We reviewed the medical records of 1,306 patients. The proportions of knee arthroplasty, hip arthroplasty, and femur fracture repair were 63.4%, 29.9%, and 6.7%, respectively. The cumulative incidence of PE and DVT in patients undergoing major orthopedic surgery was 1.99% and 2.22%, respectively. Most of the patients presented with PE and DVT (61.5% and 72.4%, respectively within the first 72 h after surgery. Patients undergoing femur fracture repair, those aged ≥ 65 years, and bedridden patients were at a higher risk for developing VTE. CONCLUSIONS: Our results show that VTE was a significant complication of major orthopedic surgery, despite the use of thromboprophylaxis. Clinicians should be aware of VTE, especially during the perioperative period and in bedridden, elderly patients (≥ 65 years of age.

  13. The effect of different surgical drilling procedures on full laser-etched microgrooves surface-treated implants: an experimental study in sheep.

    Science.gov (United States)

    Jimbo, Ryo; Tovar, Nick; Yoo, Daniel Y; Janal, Malvin N; Anchieta, Rodolfo B; Coelho, Paulo G

    2014-09-01

    To evaluate the influence of instrumentation technique on the early osseointegration histomorphometrics and biomechanical fixation of fully laser-etched microgrooves implant surfaces in a sheep model. Six sheep were subjected to bilateral hip surgeries 3 and 6 weeks before euthanasia. A total of 48 implants (∅4.5 mm, 8 mm in length) were distributed among four sites (8 per animal) and placed in bone sites drilled to 4.6 mm (reamer), 4.1 mm (loose), 3.7 mm (medium) and 3.2 mm (tight) in diameter. After healing, the animals were euthanized and half of the implants were biomechanically tested, while the remainder was subjected to non-decalcified histologic processing. The histomorphometric parameters assessed were bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Statistical analysis was performed using a mixed-model analysis of variance with significance level set at P bone seemed to be in contact to the implant surface, at 3 weeks, whereas the implants placed in press-fit situations were mainly supported by cortical bone. The laser-etched microgrooved implant presented osteoconductive and biocompatible properties for all surgical procedures tested. However, procedures providing increasingly higher press-fit scenarios presented the strongest histomorphometric and biomechanical responses at 3 and 6 weeks. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Evolving trauma and orthopedics training in the UK.

    Science.gov (United States)

    Inaparthy, Praveen K; Sayana, Murali K; Maffulli, Nicola

    2013-01-01

    The ever-growing population of the UK has resulted in increasing demands on its healthcare service. Changes have been introduced in the UK medical training system to avoid loss of training time and make it more focused and productive. Modernizing medical careers (MMC) was introduced in 2005. This promised to reduce the training period for a safe trauma specialist, in trauma and orthopedics, to 10 years. At around the same time, the European Working Time Directive (EWTD) was introduced to reduce the working hours for junior doctors in training, to improve patient safety and also work-life balance of junior doctors. Introduction of the assessment tools from Orthopedic Competency assessment project (OCAP) will help tailor the training according to the needs of the trainee. The aim of this article is to review the changes in the UK orthopedic surgical training over the past two decades. Copyright © 2012 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  15. Improving surgeon utilization in an orthopedic department using simulation modeling

    Directory of Open Access Journals (Sweden)

    Simwita YW

    2016-10-01

    Full Text Available Yusta W Simwita, Berit I Helgheim Department of Logistics, Molde University College, Molde, Norway Purpose: Worldwide more than two billion people lack appropriate access to surgical services due to mismatch between existing human resource and patient demands. Improving utilization of existing workforce capacity can reduce the existing gap between surgical demand and available workforce capacity. In this paper, the authors use discrete event simulation to explore the care process at an orthopedic department. Our main focus is improving utilization of surgeons while minimizing patient wait time.Methods: The authors collaborated with orthopedic department personnel to map the current operations of orthopedic care process in order to identify factors that influence poor surgeons utilization and high patient waiting time. The authors used an observational approach to collect data. The developed model was validated by comparing the simulation output with the actual patient data that were collected from the studied orthopedic care process. The authors developed a proposal scenario to show how to improve surgeon utilization.Results: The simulation results showed that if ancillary services could be performed before the start of clinic examination services, the orthopedic care process could be highly improved. That is, improved surgeon utilization and reduced patient waiting time. Simulation results demonstrate that with improved surgeon utilizations, up to 55% increase of future demand can be accommodated without patients reaching current waiting time at this clinic, thus, improving patient access to health care services.Conclusion: This study shows how simulation modeling can be used to improve health care processes. This study was limited to a single care process; however the findings can be applied to improve other orthopedic care process with similar operational characteristics. Keywords: waiting time, patient, health care process

  16. Applications of Metal Additive Manufacturing in Veterinary Orthopedic Surgery

    Science.gov (United States)

    Harrysson, Ola L. A.; Marcellin-Little, Denis J.; Horn, Timothy J.

    2015-03-01

    Veterinary medicine has undergone a rapid increase in specialization over the last three decades. Veterinarians now routinely perform joint replacement, neurosurgery, limb-sparing surgery, interventional radiology, radiation therapy, and other complex medical procedures. Many procedures involve advanced imaging and surgical planning. Evidence-based medicine has also become part of the modus operandi of veterinary clinicians. Modeling and additive manufacturing can provide individualized or customized therapeutic solutions to support the management of companion animals with complex medical problems. The use of metal additive manufacturing is increasing in veterinary orthopedic surgery. This review describes and discusses current and potential applications of metal additive manufacturing in veterinary orthopedic surgery.

  17. Osteogenic protein-1 increases the fixation of implants grafted with morcellised bone allograft and ProOsteon bone substitute: an experimental study in dogs

    DEFF Research Database (Denmark)

    Jensen, T B; Overgaard, S; Lind, M

    2007-01-01

    Impacted bone allograft is often used in revision joint replacement. Hydroxyapatite granules have been suggested as a substitute or to enhance morcellised bone allograft. We hypothesised that adding osteogenic protein-1 to a composite of bone allograft and non-resorbable hydroxyapatite granules...... (ProOsteon) would improve the incorporation of bone and implant fixation. We also compared the response to using ProOsteon alone against bone allograft used in isolation. We implanted two non-weight-bearing hydroxyapatite-coated implants into each proximal humerus of six dogs, with each implant...... surrounded by a concentric 3 mm gap. These gaps were randomly allocated to four different procedures in each dog: 1) bone allograft used on its own; 2) ProOsteon used on its own; 3) allograft and ProOsteon used together; or 4) allograft and ProOsteon with the addition of osteogenic protein-1. After three...

  18. [Enforcing osseointegration of dental implantates spray-coated by bioceramics with the help of hyaluronic acid and hydroxyapatite gel in experimental conditions].

    Science.gov (United States)

    Kulakov, A A; Volozhin, A I; Tkachenko, V M; Doktorov, A A; Salim, Ibrakhim Samir

    2007-01-01

    Influence of HAP-gel (2 g of 2% solution of hyaluronic acid mixed with 0,5 g of hydroxyapatite and 0,1 ml of colloidal silver) upon osseointegration in case of delayed introduction of titanium implantates in dog jaw. By scanning electron microscopy it was shown that solely use either of HAP-gel or of ceramic spraying increased direct contact area between bone and implantates in the 6 and 9 months time period. Combination of spray-coated ceramic with HAP-gel was effective in 3 months after implantation, when solely the HAP-gel or the ceramic spraying were little effective. In the following terms of experiment (6 and 9 months) significant differences between groups 3 and 4 (implantate with ceramic spraying but without HAP-gel in the alveolus and implantate with ceramic spraying and with HAP-gel in the alveolus) were not found. The area of implantate integration with jaw bone (cortical part of it was excluded) was equal to 80% and was maximal for the given conditions of the experiment.

  19. HA-Coated Implant

    DEFF Research Database (Denmark)

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    of improving the fixation of implants. Of these, hydroxyapatite (HA) is the most widely used and most extensively investigated. HA is highly osseoconductive, and the positive effect is well documented in both basic and long-term clinical research [1–6]. This chapter describes experimental and clinical studies...

  20. The prospect of carbon fiber implants in radiotherapy

    Science.gov (United States)

    Xiao‐bin, Tang; Chang‐ran, Geng; Da, Chen

    2012-01-01

    Because of their superior characteristics, carbonaceous materials, which are still at their early stage of development, have garnered significant interest. Because of their low atomic number, carbonaceous orthopedic implants possess radiation properties similar to biological tissues and, therefore, they are more suitable to patients in need of radiotherapy. The effects of stainless steel, titanium, and carbon plates on radiation dose distributions were investigated in this work using Monte Carlo simulations and TLD measurements for 6 MV photon beams. It is found that carbon plates will neither increase the incident surface dose, nor lead to the decrease of exit surface dose (the effect of a second build‐up). Carbon fiber orthopedic implants have a good prospect for radiotherapy patients because they have minimal perturbation effects on the radiotherapy dose distribution. PACS number: 87.55.K‐,87.55.Gh, 87.55.ne PMID:22766953

  1. Looking at the Social Activity for Adolescents with Orthopedic Impairments

    Science.gov (United States)

    Biastro, Leslie; Frank, Heather; Larwin, Karen H.

    2015-01-01

    Adolescents with identified orthopedic impairments are often less likely to participate in social activities outside of the school setting. However, the adolescents who are able to participate in activities have higher social skills, more academic successes, and show more satisfaction in their roles as family member or friend. The aim of this…

  2. Socioeconomic value of orthopedic devices: evidence and methodological challenges

    Directory of Open Access Journals (Sweden)

    Sorenson C

    2012-10-01

    Full Text Available Corinna Sorenson,1,2 Michael Drummond2,31LSE Health, London School of Economics, London, UK; 2European Health Technology Institute for Socioeconomic Research, Brussels, Belgium; 3Centre for Health Economics, University of York, York, UKAbstract: With continued technological advances in orthopedic devices and increasingly limited health care resources, greater attention will be placed on substantiating the socioeconomic value of these devices. Therefore, this study focused on a systematic review of available economic evaluations of selected orthopedic devices (n = 33 studies to assess their impact on different clinical and economic outcomes. The existing evidence suggests that they have important benefits to patients, including reduced risk of fractures, increased mobility and functioning, and enhanced quality of life, and do so cost effectively or with cost savings. However, we have identified several methodological obstacles to sufficient ascertainment of value, such as a lack of robust information on health economic outcomes and long-term evidence. We also identify areas where additional research is needed to assess more fully the value of orthopedic devices.Keywords: medical devices, orthopedics, health economic evaluation

  3. Survey of 2582 Cases of Acute Orthopedic Trauma

    Science.gov (United States)

    Soleymanha, Mehran; Mobayen, Mohammadreza; Asadi, Kamran; Adeli, Alborz; Haghparast-Ghadim-Limudahi, Zahra

    2014-01-01

    Background: Orthopedic injuries are among the most common causes of mortality, morbidity, hospitalization, and economic burden in societies. Objectives: In this research, we study the prevalence of different types of trauma requiring orthopedic surgery. Patients and Methods: We conducted a cross-sectional study on 2582 patients with acute orthopedic injuries admitted to the orthopedic emergency ward at the Poursina Hospital (a referral center in Guilan province (northern Iran), during December 2010 through September 2011. Patients were examined and the data collection form was filled for each patient. Data were analyzed by SPSS software version 19 and were listed in tables. Results: Of 2582 included cases, 1940 were male and 642 were female, with a mean age of 34.5 years. Most injuries were seen in the 25 to 44 year age group from rural areas. The highest frequency of trauma related to falls. On the other hand, bicycling and shooting had the lowest frequencies. There were 18 cases with limb amputation. Overall, 66.5% of patients had fractures, 5% had soft tissue lacerations, and 10% had dislocations. Conclusions: Identification of risk factors and methods of prevention is one of the most important duties of healthcare systems. Devising plans to minimize these risk factors and familiarizing people with them is prudent. PMID:25717444

  4. Rivaroxaban for Thromboprophylaxis After Nonelective Orthopedic Trauma Surgery in Switzerland

    DEFF Research Database (Denmark)

    Hoffmeyer, Pierre; Simmen, Hanspeter; Jakob, Marcel

    2017-01-01

    This study investigated the effectiveness and the outcomes of rivaroxaban vs the standard of care for venous thromboembolic prophylaxis in patients undergoing fracture-related surgery. A total of 413 patients undergoing fracture-related surgery from 9 Swiss orthopedic and trauma centers were enro...

  5. Frequency of orthopedic diseases in horses: A retrospective study

    Directory of Open Access Journals (Sweden)

    Kovač Milomir

    2002-01-01

    Full Text Available This retrospective study determined the frequency of orthopedic diseases in horses. It was possible to establish 141 specific orthopedic diagnoses in 1955 horses with lameness. In 14.58 % horses, multiple pathologic orthopedic changes were determined. In 61.84 % cases, the pathologic changes were present on the thoracic limb, 28,86 % on the pelvic limb and other parts of the oganism (neck, spine, muscles in 9.29 % cases. Pathologic changes on the tendons, ligaments, tendon sheats, bursae and muscles were determined in 31.51 % cases. Diseases of the hoof were present in 25.82 % cases. According to our investigation the most frequent orthopedic diseases are: podarthritis (acute, chronic, septic (5.04 %, navicular disease (4.69 %, tendinitis m. flexor digitalis superfacialis (4.51 %, kissing spine syndrom (4.30 % periarthritis et osteoarthrosis tarsi (3.30 %, distal metacarpal/metatarzophalengeal tendovaginitis (3.30 % and high suspensory ligament desmitis (3.12 %. Most frequent fractures were diagnosed on the metacarpal/metatarsal bone II and IV (2.56 %. Osteochondrossis dissecans was most frequently determined in the tarsocrural (1.26 % and the metacarpophalengeal joint (1.56 %.

  6. Web-based patient education in orthopedics : Systematic review

    NARCIS (Netherlands)

    Dekkers, T.; Melles, M.; Groeneveld, B.S.; de Ridder, H.

    2018-01-01

    Background: Patients with orthopedic conditions frequently use the internet to find health information. Patient education that is distributed online may form an easily accessible, time- and cost-effective alternative to education delivered through traditional channels such as one-on-one

  7. Radiation injuries to the skeleton and their orthopedic treatment

    International Nuclear Information System (INIS)

    Franz, R.; Rahnfeld, R.

    1978-01-01

    70 patients subjected to orthopedic treatment and radiotherapy for skeletal tumors have been examined. It was found that serious radiation injuries frequently occurred. Above all there were contractures, disordered healing of wounds, ulcerations, and scolioses and kyphoses of the growing skeleton. Therefore, in the case of diseases of the skeleton, it is recommended to restrain radiotherapy. It has to be rejected in child's age

  8. Orthopedic trauma surgery in the morbidly obese patient.

    Science.gov (United States)

    Bozzio, Anthony E; Gala, Raj J; Villasenor, Mario A; Hao, Jiandon; Mauffrey, Cyril

    2014-05-01

    The treatment of morbidly obese patients in orthopedic trauma differs in many ways compared to injured patients with normal body mass indices. This paper highlights key differences and ways to overcome obstacles. We present specific tips, as well as considerations for initial planning, positioning for surgery, intra-operative strategies, and a discussion on both anesthesia and imaging. Several treatment strategies have been shown to have better results in morbidly obese patients. Pre-operative planning is necessary for minimizing risk to the patient. The prevalence of morbid obesity has increased in the USA in the past quarter century. Treatment for orthopedic injuries in morbidly obese patients requires a multidisciplinary approach that addresses not only their orthopedic injuries, but also medical co-morbidities. A team of medicine doctors, anesthesiologists, X-ray technicians, physical and occupational therapists, respiratory therapists, and social workers is needed in addition to the orthopedic surgeon. Modifications in both pre-operative planning and intra-operative strategies may be necessary in order to accommodate the patient. This paper presents numerous technical tips that can aid in providing stable fixation for fractures, as well as addressing peri-operative issues specific to the morbidly obese.

  9. Readability of Orthopedic Trauma Patient Education Materials on the Internet.

    Science.gov (United States)

    Mohan, Rohith; Yi, Paul H; Morshed, Saam

    In this study, we used the Flesch-Kincaid Readability Scale to determine the readability levels of orthopedic trauma patient education materials on the American Academy of Orthopaedic Surgeons (AAOS) website and to examine how subspecialty coauthorship affects readability level. Included articles from the AAOS online patient education library and the AAOS OrthoPortal website were categorized as trauma or broken bones and injuries on the AAOS online library or were screened by study authors for relevance to orthopedic trauma. Subsequently, the Flesch-Kincaid scale was used to determine each article's readability level, which was reported as a grade level. Subspecialty coauthorship was noted for each article. A total of 115 articles from the AAOS website were included in the study and reviewed. Mean reading level was grade 9.1 for all articles reviewed. Nineteen articles (16.5%) were found to be at or below the eighth-grade level, and only 1 article was at or below the sixth-grade level. In addition, there was no statistically significant difference between articles coauthored by the various orthopedic subspecialties and those authored exclusively by AAOS. Orthopedic trauma readability materials on the AAOS website appear to be written at a reading comprehension level too high for the average patient to understand.

  10. Ion implantation

    International Nuclear Information System (INIS)

    Johnson, E.

    1986-01-01

    It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

  11. Comparison of new bone formation, implant integration, and biocompatibility between RGD-hydroxyapatite and pure hydroxyapatite coating for cementless joint prostheses--an experimental study in rabbits.

    Science.gov (United States)

    Bitschnau, Achim; Alt, Volker; Böhner, Felicitas; Heerich, Katharina Elisabeth; Margesin, Erika; Hartmann, Sonja; Sewing, Andreas; Meyer, Christof; Wenisch, Sabine; Schnettler, Reinhard

    2009-01-01

    This is the first work to report on additional Arginin-Glycin-Aspartat (RGD) coating on precoated hydroxyapatite (HA) surfaces regarding new bone formation, implant bone contact, and biocompatibility compared to pure HA coating and uncoated stainless K-wires. There were 39 rabbits in total with 6 animals for the RGD-HA and HA group for the 4 week time period and 9 animals for each of the 3 implant groups for the 12 week observation. A 2.0 K-wire either with RGD-HA or with pure HA coating or uncoated was placed into the intramedullary canal of the tibia. After 4 and 12 weeks, the tibiae were harvested and three different areas of the tibia were assessed for quantitative and qualitative histology for new bone formation, direct implant bone contact, and formation of multinucleated giant cells. Both RGD-HA and pure HA coating showed statistically higher new bone formation and implant bone contact after 12 weeks than the uncoated K-wire. There were no significant differences between the RGD-HA and the pure HA coating in new bone formation and direct implant bone contact after 4 and 12 weeks. The number of multinucleated giant did not differ significantly between the RGD-HA and HA group after both time points. Overall, no significant effects of an additional RGD coating on HA surfaces were detected in this model after 12 weeks. (c) 2008 Wiley Periodicals, Inc.

  12. Near-miss event assessment in orthopedic surgery: Antimicrobial prophylaxis noncompliance.

    Science.gov (United States)

    Bonfait, H; Delaunay, C; de Thomasson, E; Charrois, O

    2010-09-01

    Antimicrobial prophylaxis is one of the main safety measures to be enforced when implanting any medical device; surveys of practice, however, have found poor compliance. This study is based on analysis of 153 dedicated in-depth analysis forms sent to orthopedic surgeons who had reported an antimicrobial prophylaxis-related near-miss event (NME) during the year 2008 as part of their certification report to the official organization, Orthorisq (orthopaedic Patient safety risk management agency). Antimicrobial prophylaxis guidelines exist in 95% of French centers, but in 14% are not available in the right place. 88% of orthopedic surgeons consider them well-adapted to their practice. Most declarations follow fortuitous discovery by the surgeon of an immediate peri-operative malfunction. Human causes were found in 92% of declarations, general organizational causes in 50% and material causes in 28%. Regarding corrective action, 65% of respondents reported implementing a second-order procedure, and only 20% were able to resume truly regular antimicrobial prophylaxis. The main reason for poor or non-performance of antimicrobial prophylaxis was "omission by negligence or oversight", reported in 56% of declarations. Proposals for improvement were: revised antimicrobial prophylaxis guidelines specifying "who does what"; guideline awareness checks on new, temporary and locum-tenens staff; patient involvement in personal data collection; and implementation of a check-list in line with WHO and French Health Authority recommendations. These improvement proposals were taken on board in the antimicrobial prophylaxis consensus update currently being drawn up by the French Society for Anesthesia and Intensive Care. Level IV, Decision Analyses Study. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  13. Publication Productivity of Early-Career Orthopedic Trauma Surgeons.

    Science.gov (United States)

    Hake, Mark E; Lee, John J; Goulet, James A

    2016-01-01

    The goals of this study were to: (1) define the publication productivity of early-career orthopedic trauma surgeons over time; (2) compare the early-career publication productivity of recent orthopedic trauma fellowship graduates vs their more senior colleagues; and (3) determine the proportion of fellowship graduates who meet the Orthopaedic Trauma Association (OTA) publication criteria for active membership early in their careers. Orthopedic trauma fellowship graduates from 1982 to 2007 were analyzed. A literature search was performed for each fellow's publications for the 6-year period beginning the year of fellowship graduation. Publication productivity was compared between early and recent groups of graduates, 1987 to 1991 and 2003 to 2007, respectively. Fulfillment of OTA publication criteria was determined. Seventy-nine percent of graduates contributed to 1 or more publications. The recent group produced more total publications per graduate (4.06 vs 3.29, P=.01) and more coauthor publications (2.60 vs 2.04, P=.019) than the early group. The number of first-author publications did not differ between groups (1.46 vs 1.25, P=.26). A greater percentage of the recent group met current OTA publication criteria compared with the early group (51% vs 35%, P=.04). The findings showed that recent orthopedic trauma graduates had increased publication productivity compared with their more senior colleagues, although a proportion had not qualified for active OTA membership 6 years into their career. Overall, these data are encouraging and suggest that young orthopedic trauma surgeons remain committed to sustaining a high level of academic excellence. Copyright 2016, SLACK Incorporated.

  14. Surviving a Site Audit: Tips for Good Clinical Practice in an Implant Trial

    NARCIS (Netherlands)

    E.M.M. van Lieshout (Esther); S.M. Zielinski (Stephanie)

    2009-01-01

    textabstractAbstract The number of clinical trials involving implants for trauma and orthopedic surgery is increasing. The International Conference of Harmonization-Good Clinical Practice (ICH-GCP) guideline has been developed in order to assure that the rights, safety, and well-being of trial

  15. miR-451 deficiency is associated with altered endometrial fibrinogen alpha chain expression and reduced endometriotic implant establishment in an experimental mouse model.

    Directory of Open Access Journals (Sweden)

    Warren B Nothnick

    Full Text Available Endometriosis is defined as the growth of endometrial glandular and stromal components in ectopic locations and affects as many as 10% of all women of reproductive age. Despite its high prevalence, the pathogenesis of endometriosis remains poorly understood. MicroRNAs, small non-coding RNAs that post-transcriptionally regulate gene expression, are mis-expressed in endometriosis but a functional role in the disease pathogenesis remains uncertain. To examine the role of microRNA-451 (miR-451 in the initial development of endometriosis, we utilized a novel mouse model in which eutopic endometrial fragments used to induce endometriosis were deficient for miR-451. After induction of the disease, we evaluated the impact of this deficiency on implant development and survival. Loss of miR-451 expression resulted in a lower number of ectopic lesions established in vivo. Analysis of differential protein profiles between miR-451 deficient and wild-type endometrial fragments revealed that fibrinogen alpha polypeptide isoform 2 precursor was approximately 2-fold higher in the miR-451 null donor endometrial tissue and this elevated expression of the protein was associated with altered expression of the parent fibrinogen alpha chain mRNA and protein. As this polypeptide contains RGD amino acid "cell adhesion" motifs which could impact early establishment of lesion development, we examined and confirmed using a cyclic RGD peptide antagonist, that endometrial cell adhesion and endometriosis establishment could be respectively inhibited both in vitro and in vivo. Collectively, these results suggest that the reduced miR-451 eutopic endometrial expression does not enhance initial establishment of these fragments when displaced into the peritoneal cavity, that loss of eutopic endometrial miR-451 expression is associated with altered expression of fibrinogen alpha chain mRNA and protein, and that RGD cyclic peptide antagonists inhibit establishment of endometriosis

  16. Particle migration and gap healing around trabecular metal implants

    DEFF Research Database (Denmark)

    Rahbek, O; Kold, S; Zippor, Berit

    2005-01-01

    Bone on-growth and peri-implant migration of polyethylene particles were studied in an experimental setting using trabecular metal and solid metal implants. Cylindrical implants of trabecular tantalum metal and solid titanium alloy implants with a glass bead blasted surface were inserted either i...

  17. Experimental study of PLLA/INH slow release implant fabricated by three dimensional printing technique and drug release characteristics in vitro.

    Science.gov (United States)

    Wu, Gui; Wu, Weigang; Zheng, Qixin; Li, Jingfeng; Zhou, Jianbo; Hu, Zhilei

    2014-07-19

    Local slow release implant provided long term and stable drug release in the lesion. The objective of this study was to fabricate biodegradable slow release INH/PLLA tablet via 3 dimensional printing technique (3DP) and to compare the drug release characteristics of three different structured tablets in vitro. Three different drug delivery systems (columnar-shaped tablet (CST), doughnut-shaped tablet (DST) and multilayer doughnut-shaped tablet (MDST)) were manufactured by the three dimensional printing machine and isoniazid was loaded into the implant. Dynamic soaking method was used to study the drug release characteristics of the three implants. MTT cytotoxicity test and direct contact test were utilized to study the biocompatibility of the implant. The microstructures of the implants' surfaces were observed with electron microscope. The PLLA powder in the tablet could be excellently combined through 3DP without disintegration. Electron microscope observations showed that INH distributed evenly on the surface of the tablet in a "nest-shaped" way, while the surface of the barrier layer in the multilayer doughnut shaped tablet was compact and did not contain INH. The concentration of INH in all of the three tablets were still higher than the effective bacteriostasis concentration (Isoniazid: 0.025 ~ 0.05 μg/ml) after 30 day's release in vitro. All of the tablets showed initial burst release of the INH in the early period. Drug concentration of MDST became stable and had little fluctuation starting from the 6th day of the release. Drug concentration of DST and CST decreased gradually and the rate of decrease in concentration was faster in DST than CST. MTT cytotoxicity test and direct contact test indicated that the INH-PLLA tablet had low cytotoxicity and favorable biocompatibility. Three dimensional printing technique was a reliable technique to fabricate complicated implants. Drug release pattern in MDST was the most stable among the three implants. It was

  18. Efectos de diferentes tratamientos antiosteoporóticos sobre la osteointegración de implantes dentales en un modelo experimental en conejos

    OpenAIRE

    Almagro Fernández, María Isabel

    2011-01-01

    Los ensayos clínicos sugieren que la pérdida de masa ósea con el deterioro de la microarquitectura que caracteriza a la osteoporosis se considera un factor de riesgo para la osteointegración de los implantes dentales. Sin embargo, existen pocos estudios comparativos que proporcionen información sobre los efectos que el tratamiento antiosteoporótico provoca en la osteointegración de implantes dentales en estos pacientes. La hipótesis de esta tesis es que el tratamiento antiosteo...

  19. A comparative study of zirconium and titanium implants in rat: osseointegration and bone material quality.

    Science.gov (United States)

    Hoerth, Rebecca M; Katunar, María R; Gomez Sanchez, Andrea; Orellano, Juan C; Ceré, Silvia M; Wagermaier, Wolfgang; Ballarre, Josefina

    2014-02-01

    Permanent metal implants are widely used in human medical treatments and orthopedics, for example as hip joint replacements. They are commonly made of titanium alloys and beyond the optimization of this established material, it is also essential to explore alternative implant materials in view of improved osseointegration. The aim of our study was to characterize the implant performance of zirconium in comparison to titanium implants. Zirconium implants have been characterized in a previous study concerning material properties and surface characteristics in vitro, such as oxide layer thickness and surface roughness. In the present study, we compare bone material quality around zirconium and titanium implants in terms of osseointegration and therefore characterized bone material properties in a rat model using a multi-method approach. We used light and electron microscopy, micro Raman spectroscopy, micro X-ray fluorescence and X-ray scattering techniques to investigate the osseointegration in terms of compositional and structural properties of the newly formed bone. Regarding the mineralization level, the mineral composition, and the alignment and order of the mineral particles, our results show that the maturity of the newly formed bone after 8 weeks of implantation is already very high. In conclusion, the bone material quality obtained for zirconium implants is at least as good as for titanium. It seems that the zirconium implants can be a good candidate for using as permanent metal prosthesis for orthopedic treatments.

  20. Characteristics of Orthopedic Publications in High-Impact General Medical Journals.

    Science.gov (United States)

    Nwachukwu, Benedict U; Kahlenberg, Cynthia A; Lehman, Jason D; Lyman, Stephen; Marx, Robert G

    2017-05-01

    Orthopedic studies are occasionally published in high-impact general medical journals; these studies are often given high visibility and have significant potential to impact health care policy and inform clinical decision-making. The purpose of this review was to investigate the characteristics of operative orthopedic studies published in high-impact medical journals. The number of orthopedic studies published in high-impact medical journals is relatively low; however, these studies demonstrate methodological characteristics that may bias toward nonoperative treatment. Careful analysis and interpretation of orthopedic studies published in these journals is warranted. [Orthopedics. 2017; 40(3):e405-e412.]. Copyright 2017, SLACK Incorporated.

  1. Monitoring of implanted stem cell migration in vivo: A highly resolved in vivo magnetic resonance imaging investigation of experimental stroke in rat

    Science.gov (United States)

    Hoehn, Mathias; Küstermann, Ekkehard; Blunk, James; Wiedermann, Dirk; Trapp, Thorsten; Wecker, Stefan; Föcking, Melanie; Arnold, Heinz; Hescheler, Jürgen; Fleischmann, Bernd K.; Schwindt, Wolfram; Bührle, Christian

    2002-01-01

    In vivo monitoring of stem cells after grafting is essential for a better understanding of their migrational dynamics and differentiation processes and of their regeneration potential. Migration of endogenous or grafted stem cells and neurons has been described in vertebrate brain, both under normal conditions from the subventricular zone along the rostral migratory stream and under pathophysiological conditions, such as degeneration or focal cerebral ischemia. Those studies, however, relied on invasive analysis of brain sections in combination with appropriate staining techniques. Here, we demonstrate the observation of cell migration under in vivo conditions, allowing the monitoring of the cell dynamics within individual animals, and for a prolonged time. Embryonic stem (ES) cells, constitutively expressing the GFP, were labeled by a lipofection procedure with a MRI contrast agent and implanted into rat brains. Focal cerebral ischemia had been induced 2 weeks before implantation of ES cells into the healthy, contralateral hemisphere. MRI at 78-μm isotropic spatial resolution permitted the observation of the implanted cells with high contrast against the host tissue, and was confirmed by GFP registration. During 3 weeks, cells migrated along the corpus callosum to the ventricular walls, and massively populated the borderzone of the damaged brain tissue on the hemisphere opposite to the implantation sites. Our results indicate that ES cells have high migrational dynamics, targeted to the cerebral lesion area. The imaging approach is ideally suited for the noninvasive observation of cell migration, engraftment, and morphological differentiation at high spatial and temporal resolution. PMID:12444255

  2. Effects of orthopedic insoles on static balance of older adults wearing thick socks.

    Science.gov (United States)

    Ma, Christina Zong-Hao; Wong, Duo Wai-Chi; Wan, Anson Hong-Ping; Lee, Winson Chiu-Chun

    2018-06-01

    The wearing of socks and insoles may affect the ability of the foot to detect tactile input influencing postural balance. The aim of this study was to investigate whether (1) thick socks adversely affected the elderly postural balance and (2) orthopedic insoles could improve the elderly postural balance while wearing thick socks. Repeated-measures study design. In total, 14 healthy older adults were recruited. A monofilament test was conducted to evaluate foot plantar sensation with and without thick socks. Subjects then performed the Romberg tests under three conditions: (1) barefoot, (2) with socks only, and (3) with both socks and insoles. Postural balance was assessed by measuring the center of pressure movement during standing in each experimental condition. Thick socks significantly decreased the monofilament score ( p thick socks ( p thick socks reduces plantar pressure sensitivity and increases postural sway which may increase risk of falls. Orthopedic insoles and footwear with similar design could potentially be a cost-effective method in maintaining postural balance when wearing thick socks.

  3. The Effect of Listening to Music on Postoperative Pain in Adult Orthopedic Patients.

    Science.gov (United States)

    Schneider, Melissa A

    2018-03-01

    Pain is a common occurrence after orthopedic surgery. Patients need additional resources to manage their pain. The purpose of this study was to determine if listening to music has a positive effect on pain scores and satisfaction in the postoperative adult orthopedic patient. There are limited studies demonstrating statistically significant decreases in postoperative pain in this group. A secondary purpose was to expose nurses on a standard medical-surgical unit to an intervention, supported by the holistic nursing model that they could use in their care. This study was a descriptive, comparative, quasi-experimental design. Patients listened to prerecorded music on individual CD players and recorded pre-post pain scores with the intervention. A satisfactory survey was completed at discharge. Results demonstrated a statistically significant reduction in patients' pain scores after listening to music. Length of listening time had no effect. Patients expressed overall satisfaction, and 100% of participants would recommend this intervention to others. Listening to music is beneficial as an adjunct to pain medication and contributes to increased patient satisfaction. It is hoped that the information gained from this study will lead to an enhancement in the standard of care for postoperative patients.

  4. Pedicle screws with a thin hydroxyapatite coating for improving fixation at the bone-implant interface in the osteoporotic spine: experimental study in a porcine model.

    Science.gov (United States)

    Ohe, Makoto; Moridaira, Hiroshi; Inami, Satoshi; Takeuchi, Daisaku; Nohara, Yutaka; Taneichi, Hiroshi

    2018-03-30

    OBJECTIVE Instrumentation failure caused by the loosening of pedicle screws (PSs) in patients with osteoporosis is a serious problem after spinal surgery. The addition of a thin hydroxyapatite (HA) surface coating applied by using a sputtering process was reported recently to be a promising method for providing bone conduction around an implant without a significant risk of coating-layer breakage. In this study, the authors evaluated the biomechanical and histological features of the bone-implant interface (BII) of PSs with a thin HA coating in an in vivo porcine osteoporotic spine model. METHODS Three types of PSs (untreated/standard [STPS], sandblasted [BLPS], and HA-coated [HAPS] PSs) were implanted into the thoracic and lumbar spine (T9-L6) of 8 mature Clawn miniature pigs (6 ovariectomized [osteoporosis group] and 2 sham-operated [control group] pigs). The spines were harvested from the osteoporosis group at 0, 2, 4, 8, 12, or 24 weeks after PS placement and from the control group at 0 or 24 weeks. Their bone mineral density (BMD) was measured by peripheral quantitative CT. Histological evaluation of the BIIs was conducted by performing bone volume/tissue volume and bone surface/implant surface measurements. The strength of the BII was evaluated with extraction torque testing. RESULTS The BMD decreased significantly in the osteoporosis group (p < 0.01). HAPSs exhibited the greatest mean extraction peak torque at 8 weeks, and HAPSs and BLPSs exhibited significantly greater mean torque than the STPSs at 12 weeks (p < 0.05). The bone surface/implant surface ratio was significantly higher for HAPSs than for STPSs after 2 weeks (p < 0.05), and bonding between bone and the implant surface was maintained until 24 weeks with no detachment of the coating layer. In contrast, the bone volume/tissue volume ratio was significantly higher for HAPSs than for BLPSs or STPSs only at 4 weeks. CONCLUSIONS Using PSs with a thin HA coating applied using a sputtering process

  5. Lithium chloride enhances bone regeneration and implant osseointegration in osteoporotic conditions.

    Science.gov (United States)

    Jin, Yifan; Xu, Lihua; Hu, Xiaohui; Liao, Shixian; Pathak, Janak L; Liu, Jinsong

    2016-10-06

    Osteoporotic patients have a high risk of dental and orthopedic implant failure. Lithium chloride (LiCl) has been reported to enhance bone formation. However, the role of LiCl in the success rate of dental and orthopedic implants in osteoporotic conditions is still unknown. We investigated whether LiCl enhances implant osseointegration, implant fixation, and bone formation in osteoporotic conditions. Sprague-Dawley female rats (n = 18) were ovariectomized (OVX) to induce osteoporosis, and another nine rats underwent sham surgery. Three months after surgery, titanium implants were implanted in the tibia of the OVX and sham group rats. After implantation, the OVX rats were gavaged with 150 mg/kg/2 days of LiCl (OVX + LiCl group) or saline (OVX group), and sham group rats were gavaged with saline for 3 months. Implant osseointegration and bone formation were analyzed using histology, biomechanical testing, and micro computed tomography (micro-CT). More bone loss was observed in the OVX group compared to the control, and LiCl treatment enhanced bone formation and implant fixation in osteoporotic rats. In the OVX group, bone-implant contact (BIC) was decreased by 81.2 % compared to the sham group. Interestingly, the OVX + LiCl group showed 4.4-fold higher BIC compared to the OVX group. Micro-CT data of tibia from the OVX + LiCl group showed higher bone volume, trabecular thickness, trabecular number, and osseointegration compared to the OVX group. Maximum push-out force and implant-bone interface shear strength were 2.9-fold stronger in the OVX + LiCl group compared to the OVX group. In conclusion, LiCl enhanced implant osseointegration, implant fixation, and bone formation in osteoporotic conditions, suggesting LiCl as a promising therapeutic agent to prevent implant failure and bone loss in osteoporotic conditions.

  6. Implantable wireless powered light emitting diode (LED) for near-infrared photoimmunotherapy: device development and experimental assessment in vitro and in vivo.

    Science.gov (United States)

    Nakajima, Kohei; Kimura, Toshihiro; Takakura, Hideo; Yoshikawa, Yasuo; Kameda, Atsushi; Shindo, Takayuki; Sato, Kazuhide; Kobayashi, Hisataka; Ogawa, Mikako

    2018-04-13

    The aim of this study was to develop and assess a novel implantable, wireless-powered, light-emitting diode (LED) for near-infrared photoimmunotherapy (NIR-PIT). NIR-PIT is a recently developed cancer therapy that uses NIR light and antibody-photosensitizer conjugates and is able to induce cancer-specific cell death. Due to limited light penetration depth it is currently unable to treat tumors in deep tissues. Use of implanted LED might potentially overcome this limitation. The wireless LED system was able to emit NIR light up to a distance of 20 cm from the transmitter coil by using low magnetic fields as compliant with limits for use in humans. Results indicated that the LED system was able to kill tumor cells in vitro and to suppress tumor growth in implanted tumor-bearing mice. Results indicated that the proposed implantable wireless LED system was able to suppress tumor growth in vivo . These results are encouraging as wireless LED systems such as the one here developed might be a possible solution to treat tumors in deep regions in humans. Further research in this area would be important. An implantable LED system was developed. It consisted of a LED capsule including two LED sources and a receiver coil coupled with an external coil and power source. Wireless power transmission was guaranteed by using electromagnetic induction. The system was tested in vitro by using EGFR-expressing cells and HER2-expressing cells. The system was also tested in vivo in tumor-bearing mice.

  7. Carmustine Implant

    Science.gov (United States)

    ... works by slowing or stopping the growth of cancer cells in your body. ... are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving carmustine implant, call your doctor. Carmustine may harm the fetus.

  8. Cochlear Implants

    Science.gov (United States)

    ... NIDCD A cochlear implant is a small, complex electronic device that can help to provide a sense ... Hearing Aids Retinitis Pigmentosa - National Eye Institute Telecommunications Relay Services Usher Syndrome Your Baby's Hearing Screening News ...

  9. Scientific justification of development of domestic attachments and their clinic-biomechanical assessment of effectiveness at a denture with use of implants

    OpenAIRE

    SALIMOV ODILKHON

    2016-01-01

    Motivation to use of implantation artificial limbs are high esthetic and adaptation opportunities of such designs. However, treatment with use of implants has the increased risk of complications. Fixing of an orthopedic design to implants is the reason of one of widespread complications. Along with it, high cost of import production limits possibility of their broad application. Localization of development and production of latch fastenings from domestic materials will allow improving renderi...

  10. Additive manufacturing technologies of porous metal implants

    Directory of Open Access Journals (Sweden)

    Yang Quanzhan

    2014-06-01

    Full Text Available Biomedical metal materials with good corrosion resistance and mechanical properties are widely used in orthopedic surgery and dental implant materials, but they can easily cause stress shielding due to the significant difference in elastic modulus between the implant and human bones. The elastic modulus of porous metals is lower than that of dense metals. Therefore, it is possible to adjust the pore parameters to make the elastic modulus of porous metals match or be comparable with that of the bone tissue. At the same time, the open porous metals with pores connected to each other could provide the structural condition for bone ingrowth, which is helpful in strengthening the biological combination of bone tissue with the implants. Therefore, the preparation technologies of porous metal implants and related research have been drawing more and more attention due to the excellent features of porous metals. Selective laser melting (SLM and electron beam melting technology (EBM are important research fields of additive manufacturing. They have the advantages of directly forming arbitrarily complex shaped metal parts which are suitable for the preparation of porous metal implants with complex shape and fine structure. As new manufacturing technologies, the applications of SLM and EBM for porous metal implants have just begun. This paper aims to understand the technology status of SLM and EBM, the research progress of porous metal implants preparation by using SLM and EBM, and the biological compatibility of the materials, individual design and manufacturing requirements. The existing problems and future research directions for porous metal implants prepared by SLM and EBM methods are discussed in the last paragraph.

  11. Listening to Brain Microcircuits for Interfacing With External World-Progress in Wireless Implantable Microelectronic Neuroengineering Devices: Experimental systems are described for electrical recording in the brain using multiple microelectrodes and short range implantable or wearable broadcasting units.

    Science.gov (United States)

    Nurmikko, Arto V; Donoghue, John P; Hochberg, Leigh R; Patterson, William R; Song, Yoon-Kyu; Bull, Christopher W; Borton, David A; Laiwalla, Farah; Park, Sunmee; Ming, Yin; Aceros, Juan

    2010-01-01

    Acquiring neural signals at high spatial and temporal resolution directly from brain microcircuits and decoding their activity to interpret commands and/or prior planning activity, such as motion of an arm or a leg, is a prime goal of modern neurotechnology. Its practical aims include assistive devices for subjects whose normal neural information pathways are not functioning due to physical damage or disease. On the fundamental side, researchers are striving to decipher the code of multiple neural microcircuits which collectively make up nature's amazing computing machine, the brain. By implanting biocompatible neural sensor probes directly into the brain, in the form of microelectrode arrays, it is now possible to extract information from interacting populations of neural cells with spatial and temporal resolution at the single cell level. With parallel advances in application of statistical and mathematical techniques tools for deciphering the neural code, extracted populations or correlated neurons, significant understanding has been achieved of those brain commands that control, e.g., the motion of an arm in a primate (monkey or a human subject). These developments are accelerating the work on neural prosthetics where brain derived signals may be employed to bypass, e.g., an injured spinal cord. One key element in achieving the goals for practical and versatile neural prostheses is the development of fully implantable wireless microelectronic "brain-interfaces" within the body, a point of special emphasis of this paper.

  12. Ion implantation and amorphous metals

    International Nuclear Information System (INIS)

    Hohmuth, K.; Rauschenbach, B.

    1981-01-01

    This review deals with ion implantation of metals in the high concentration range for preparing amorphous layers (>= 10 at%, implantation doses > 10 16 ions/cm 2 ). Different models are described concerning formation of amorphous phases of metals by ion implantation and experimental results are given. The study of amorphous phases has been carried out by the aid of Rutherford backscattering combined with the channeling technique and using transmission electron microscopy. The structure of amorphous metals prepared by ion implantation has been discussed. It was concluded that amorphous metal-metalloid compounds can be described by a dense-random-packing structure with a great portion of metal atoms. Ion implantation has been compared with other techniques for preparing amorphous metals and the adventages have been outlined

  13. Cutaneous and systemic hypersensitivity reactions to metallic implants

    DEFF Research Database (Denmark)

    Basko-Plluska, Juliana L; Thyssen, Jacob P; Schalock, Peter C

    2011-01-01

    ) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions......Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous......, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure...

  14. Evaluation of Patient Radiation Dose during Orthopedic Surgery

    International Nuclear Information System (INIS)

    Osman, H; Elzaki, A.; Sam, A.K.; Sulieman, A.

    2013-01-01

    The number of orthopedic procedures requiring the use of the fluoroscopic guidance has increased over the recent years. Consequently the patient exposed to un avoidable radiation doses. The aim of the current study was to evaluate patient radiation dose during these procedures.37 patients under went dynamic hip screw (DHS) and dynamic cannulated screw (DCS) were evaluated using calibrated Thermolumincent Dosimeters (TLDs), under carm fluoroscopic machines ,in three centers in Khartoum-Sudan. The mean Entrance Skin Dose (ESD) was 7.9 m Gy per procedure. The bone marrow and gonad organ exposed to significant doses. No correlation was found between ESD and Body Mass Index (BMI), or patient weight. Well correlation was found between kilo voltage applied and ESD. Orthopedic surgeries delivered lower radiation dose to patients than cardiac catheterization or hysterosalpingraphy (HSG) procedures. More study should be implemented to follow radiation dose before surgery and after surgery

  15. Osseointegration of Plateau Root Form Implants: Unique Healing Pathway Leading to Haversian-Like Long-Term Morphology.

    Science.gov (United States)

    Coelho, Paulo G; Suzuki, Marcelo; Marin, Charles; Granato, Rodrigo; Gil, Luis F; Tovar, Nick; Jimbo, Ryo; Neiva, Rodrigo; Bonfante, Estevam A

    2015-01-01

    Endosteal dental implants have been utilized as anchors for dental and orthopedic rehabilitations for decades with one of the highest treatment success rates in medicine. Such success is due to the phenomenon of osseointegration where after the implant surgical placement, bone healing results into an intimate contact between bone and implant surface. While osseointegration is an established phenomenon, the route which osseointegration occurs around endosteal implants is related to various implant design factors including surgical instrumentation and implant macro, micro, and nanometer scale geometry. In an implant system where void spaces (healing chambers) are present between the implant and bone immediately after placement, its inherent bone healing pathway results in unique opportunities to accelerate the osseointegration phenomenon at the short-term and its maintenance on the long-term through a haversian-like bone morphology and mechanical properties.

  16. Web-Based Patient Education in Orthopedics: Systematic Review.

    Science.gov (United States)

    Dekkers, Tessa; Melles, Marijke; Groeneveld, Bob Sander; de Ridder, Huib

    2018-04-23

    Patients with orthopedic conditions frequently use the internet to find health information. Patient education that is distributed online may form an easily accessible, time- and cost-effective alternative to education delivered through traditional channels such as one-on-one consultations or booklets. However, no systematic evidence for the comparative effectiveness of Web-based educational interventions exists. The objective of this systematic review was to examine the effects of Web-based patient education interventions for adult orthopedic patients and to compare its effectiveness with generic health information websites and traditional forms of patient education. CINAHL, the Cochrane Library, EMBASE, MEDLINE, PsycINFO, PUBMED, ScienceDirect, Scopus, and Web of Science were searched covering the period from 1995 to 2016. Peer-reviewed English and Dutch studies were included if they delivered patient education via the internet to the adult orthopedic population and assessed its effects in a controlled or observational trial. A total of 10 trials reported in 14 studies involving 4172 patients were identified. Nine trials provided evidence for increased patients' knowledge after Web-based patient education. Seven trials reported increased satisfaction and good evaluations of Web-based patient education. No compelling evidence exists for an effect of Web-based patient education on anxiety, health attitudes and behavior, or clinical outcomes. Web-based patient education may be offered as a time- and cost-effective alternative to current educational interventions when the objective is to improve patients' knowledge and satisfaction. However, these findings may not be representative for the whole orthopedic patient population as most trials included considerably younger, higher-educated, and internet-savvy participants only. ©Tessa Dekkers, Marijke Melles, Bob Sander Groeneveld, Huib de Ridder. Originally published in the Journal of Medical Internet Research (http

  17. Web-Based Patient Education in Orthopedics: Systematic Review

    Science.gov (United States)

    Melles, Marijke; Groeneveld, Bob Sander; de Ridder, Huib

    2018-01-01

    Background Patients with orthopedic conditions frequently use the internet to find health information. Patient education that is distributed online may form an easily accessible, time- and cost-effective alternative to education delivered through traditional channels such as one-on-one consultations or booklets. However, no systematic evidence for the comparative effectiveness of Web-based educational interventions exists. Objective The objective of this systematic review was to examine the effects of Web-based patient education interventions for adult orthopedic patients and to compare its effectiveness with generic health information websites and traditional forms of patient education. Methods CINAHL, the Cochrane Library, EMBASE, MEDLINE, PsycINFO, PUBMED, ScienceDirect, Scopus, and Web of Science were searched covering the period from 1995 to 2016. Peer-reviewed English and Dutch studies were included if they delivered patient education via the internet to the adult orthopedic population and assessed its effects in a controlled or observational trial. Results A total of 10 trials reported in 14 studies involving 4172 patients were identified. Nine trials provided evidence for increased patients’ knowledge after Web-based patient education. Seven trials reported increased satisfaction and good evaluations of Web-based patient education. No compelling evidence exists for an effect of Web-based patient education on anxiety, health attitudes and behavior, or clinical outcomes. Conclusions Web-based patient education may be offered as a time- and cost-effective alternative to current educational interventions when the objective is to improve patients’ knowledge and satisfaction. However, these findings may not be representative for the whole orthopedic patient population as most trials included considerably younger, higher-educated, and internet-savvy participants only. PMID:29685869

  18. Medication Review and Patient Outcomes in an Orthopedic Department

    DEFF Research Database (Denmark)

    Lisby, Marianne; Bonnerup, Dorthe Krogsgaard; Brock, Birgitte

    2015-01-01

    OBJECTIVE: We investigated the health-related effect of systematic medication review performed by a clinical pharmacist and a clinical pharmacologist on nonelective elderly orthopedic patients. METHODS: This is a nonblinded randomized controlled study of 108 patients 65 years or older treated...... with at least 4 drugs. For the intervention, the clinical pharmacist reviewed the participants' medication after completion of the usual medication routine. Information was collected from medical charts, interviews with participants, and database registrations of drug purchase. Results were conferred...

  19. Serious Leisure and People with Orthopedic Impairment: Benefits and Constraints

    OpenAIRE

    Manolya AKSATAN; Zehra Gökçe SEL

    2017-01-01

    There are many people around the world who have different types of disabilities. Understanding their needs is the first step of developing policies to increase their quality of life and satisfaction. Leisure is an essential need of disabled people and it plays an important role in disabled people’s lives. The purpose of this study is to gain a deep understanding on the serious leisure activities of people with orthopedic impairment, and also both benefits and constraints ...

  20. Wound healing in immediately loaded implants.

    Science.gov (United States)

    Romanos, Georgios E

    2015-06-01

    The orthopedic field has accumulated ample evidence that bone formation is related to functional loading and in general to physical activity. However, despite evidence that immediately loaded implants can be predictably successful, many clinicians still use the classical (delayed loading) treatment protocol. This paper examines the effects of loading on dental implants and discusses the advantages of immediate loading. The role of loading on augmented alveolar ridges is also addressed and provides evidence that early bone resorption may be controlled when bone is functionally loaded. Similar data are emerging for advanced augmentation techniques in order to control crestal bone loss. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Structural-chemical characteristics of implanted metals

    International Nuclear Information System (INIS)

    Kozejkin, B.V.; Pavlov, P.V.; Pitirimova, E.A.; Frolov, A.I.

    1988-01-01

    Corrosion and structural characteristics of metallic layers implanted by ions of chemically active impurities and noble gases are studied. Dependence of experimental results on parameters of initial materials and technological conditions of implantation is established. In studying corrosion characteristics of implanted metals a strong dependence of chemical passivation effect on technological conditions of ion-implantation and structure of initial material is stated. On the basis of developed mathematical model of chemical passivation effect it is shown that increase of corrosion characteristics of implanted metals is defined by superposition of surface and volumetric mechanisms

  2. Postoperative constipation risk assessment in Turkish orthopedic patients.

    Science.gov (United States)

    Şendir, Merdiye; Büyükıylmaz, Funda; Aştı, Türkinaz; Gürpınar, Şengül; Yazgan, İlknur

    2012-01-01

    This descriptive, correlational study was conducted to describe constipation risk assessment and the affecting factors of constipation risk of patients who have undergone major orthopedic surgery. Data were collected using a patient information form and the Constipation Risk Assessment Scale (CRAS) on the second postoperative day. Data were analyzed using the SPSS version 11.5 for Windows. The mean age of the 83 patients studied was 53.75 ± 21.29 years. Subjects were hospitalized in the orthopedic wards for 14.39 ± 15.17 days, and their current bowel habit was 2.18 ± 1.80 stools per week. Of the sample, 63.9% were female, 69.9% of the patients had a history of previous surgery, 45.8% had hip/knee arthroplasty surgery, and 55.4% had bowel problems during the hospitalization period. Patients had a medium risk for constipation according to the CRAS subscale (gender, mobility, and pharmacological agents). Total CRAS score was 12.73 ± 4.75 (medium risk) on the second postoperative day. In addition, age, marital status, educational level, having a history of surgery, and bowel elimination problems did have a significant effect on constipation risk. On the basis of the findings from this study, nurses must learn the postoperative constipation risk of orthopedic patients to implement safe and effective interventions.

  3. Questionable Word Choice in Scientific Writing in Orthopedic Surgery

    Directory of Open Access Journals (Sweden)

    Casey M. O`Connor

    2017-07-01

    Full Text Available Background: Given the strong influence of thoughts, emotions, and behaviors on musculoskeletal symptoms andlimitations it’s important that both scientific and lay writing use the most positive, hopeful, and adaptive words andconcepts consistent with medical evidence. The use of words that might reinforce misconceptions about preferencesensitiveconditions (particularly those associated with age could increase symptoms and limitations and might alsodistract patients from the treatment preferences they would select when informed and at ease.Methods: We reviewed 100 consecutive papers published in 2014 and 2015 in 6 orthopedic surgery scientific journals.We counted the number and proportion of journal articles with questionable use of one or more of the following words:tear, aggressive, required, and fail. For each word, we counted the rate of misuse per journal and the number of specificterms misused per article per journalResults: Eighty percent of all orthopedic scientific articles reviewed had questionable use of at least one term. Tearwas most questionably used with respect to rotator cuff pathology. The words fail and require were the most commonquestionably used terms overall.Conclusion: The use of questionable words and concepts is common in scientific writing in orthopedic surgery. It’sworth considering whether traditional ways or referring to musculoskeletal illness merit rephrasing.

  4. Comparing consensus guidelines on thromboprophylaxis in orthopedic surgery.

    Science.gov (United States)

    Struijk-Mulder, M C; Ettema, H B; Verheyen, C C; Büller, H R

    2010-04-01

    Different guidelines exist regarding the prevention of venous thromboembolism (VTE) in orthopedic surgery. We aimed to compare (inter)national guidelines and analyse differences. MEDLINE, the Cochrane Library and the internet were searched for guidelines on the prevention of VTE in orthopedic surgery. From these, we constructed a table comparing the different antithrombotic regimens during different orthopedic surgical and plaster cast treatments. Eleven guidelines from nine different countries and one international guideline were included. Few guidelines advise on thrombosis prophylaxis after plaster cast immobilization, (prolonged) arthroscopic surgery and isolated lower extremity trauma. Different opinions exist on the sole use of aspirin and mechanical prophylaxis and on the use of vitamin K antagonists after major hip and knee surgery. Based on the same available literature, different guidelines recommend different thromboprophylactic regimens. Ideally, the grade of recommendation should be based on the same level of evidence world-wide. Whilst there is no agreement on the relevance of different endpoints (e.g. asymptomatic DVT), it is very difficult to reach a consensus. Thromboprophylaxis guidelines should be reviewed and updated on a regular basis, because the evidence is evolving rapidly.

  5. [Orthopedic and trauma surgery in the German DRG System 2007].

    Science.gov (United States)

    Franz, D; Kaufmann, M; Siebert, C H; Windolf, J; Roeder, N

    2007-03-01

    The German Diagnosis-Related Groups (DRG) System was further developed into its 2007 version. For orthopedic and trauma surgery, significant changes were made in terms of the coding of diagnoses and medical procedures, as well as in the DRG structure itself. The German Societies for Trauma Surgery and for Orthopedics and Orthopedic Surgery (Deutsch Gesellschaft für Unfallchirurgie, DGU; and Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie, DGOOC) once again cooperated constructively with the German DRG Institute InEK. Among other innovations, new International Classification of Diseases (ICD) codes for second-degree burns were implemented. Procedure codes for joint operations, endoprosthetic-surgery and spine surgery were restructured. Furthermore, a specific code for septic surgery was introduced in 2007. In addition, the DRG structure was improved. Case allocation of patients with more than one significant operation was established. Further DRG subdivisions were established according to the patients age and the Patient Clinical Complexity Level (PCCL). DRG developments for 2007 have improved appropriate case allocation, but once again increased the system's complexity. Clinicians need an ever growing amount of specific coding know-how. Still, further adjustments to the German DRG system are required to allow for a correct allocation of cases and funds.

  6. Use of Google Scholar public profiles in orthopedics.

    Science.gov (United States)

    Tetsworth, Kevin; Fraser, Dave; Glatt, Vaida; Hohmann, Erik

    2017-01-01

    The purpose of this study was to survey the growth of Google Scholar public profiles in orthopedics over a 12-month period and to investigate global patterns. Data was prospectively acquired from June 2013 to June 2014. Google Scholar queries specific to orthopedic surgery were performed at 90-day intervals. Demographic aspects of each user were also compiled, including gender, current location, and primary interests. To determine differences between the growth of Google Scholar public profile registrations and citation counts, as well as differences in growth in different regions, repeated measures of analysis of variance (RMANOVA) were used. RMANOVA revealed statistically significant differences ( p = 0.0001) for regional growth. The largest growth was observed in the United Kingdom ( p = 0.009, 289%), followed by the Asia-Pacific region ( p = 0.004, 177%) and "Other" ( p = 0.006, 172%). The mean growth per 90-day interval is 19.9% ( p = 0.003) and the mean 12-month growth is 107% ( p = 0.05). Statistically significant differences between gender (male vs. female) and basic and clinical sciences ( χ 2 = 22.4, p = 0.0001) were observed. This study suggests an exponential growth in the number of authors in the field of orthopedic surgery creating a Google Scholar public profile, and at the current rate participation doubles every 10.6 months.

  7. Implantation, recoil implantation, and sputtering

    International Nuclear Information System (INIS)

    Kelly, R.

    1984-01-01

    The implantation and sputtering mechanisms which are relevant to ion bombardment of surfaces are described. These are: collision, thermal, electronic and photon-induced sputtering. 135 refs.; 36 figs.; 9 tabs

  8. Electrophoretic-deposited novel ternary silk fibroin/graphene oxide/hydroxyapatite nanocomposite coatings on titanium substrate for orthopedic applications

    Science.gov (United States)

    Li, Ming; Xiong, Pan; Mo, Maosong; Cheng, Yan; Zheng, Yufeng

    2016-09-01

    The combination of graphene oxide (GO) with robust mechanical property, silk fibroin (SF) with fascinating biological effects and hydroxyapatite (HA) with superior osteogenic activity is a competitive approach to make novel coatings for orthopedic applications. Herein, the feasibility of depositing ternary SF/GO/HA nanocomposite coatings on Ti substrate was firstly verified by exploiting electrophoretic nanotechnology, with SF being used as both a charging additive and a dispersion agent. The surface morphology, microstructure and composition, in vitro hemocompatibility and in vitro cytocompatibility of the resulting coatings were investigated by SEM, Raman, FTIR spectra and biocompatibility tests. Results demonstrated that GO, HA and SF could be co-deposited with a uniform, smooth thin-film morphology. The hemolysis rate analysis and the platelet adhesion test indicated good blood compatibility of the coatings. The human osteosarcoma MG63 cells displayed well adhesion and proliferation behaviors on the prepared coatings, with enhanced ALP activities. The present study suggested that SF/GO/HA nanocomposite coatings could be a promising candidate for the surface functionalization of biomaterials, especially as orthopedic implant coating.

  9. An experimental test of stroke recovery by implanting a hyaluronic acid hydrogel carrying a Nogo receptor antibody in a rat model

    International Nuclear Information System (INIS)

    Ma Jun; Tian Weiming; Hou Shaoping; Xu Qunyuan; Spector, Myron; Cui Fuzhai

    2007-01-01

    The objective of the study was to determine the effects of a hyaluronic-acid-based (HA-based) hydrogel implant, carrying a polyclonal antibody to the Nogo-66 receptor (NgR), on adult rats that underwent middle cerebral artery occlusion (MCAO). Behavioral tests of a forelimb-reaching task suggested that the disabled function of the impaired forelimb in this stroke model was ameliorated by the implant to a certain extent. These behavioral findings were correlated with immunohistochemical results of investigating the distribution of NgR antibody, neurofilaments (NF) and neuron-specific class III β-tubulin (TuJ1) in the brain sections. The porous hydrogel functioned as a scaffold to deliver the NgR antibody, support cell migration and development. In addition, it was found NF-positive and TuJ1-positive expressions were distributed in the implanted hydrogel. Collectively, the results demonstrate the promise of the HA hydrogel as a scaffold material and the delivery vehicle of the NgR antibody for the repair of defects and the support of neural regeneration in the brain

  10. An experimental test of stroke recovery by implanting a hyaluronic acid hydrogel carrying a Nogo receptor antibody in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jun [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Tian Weiming [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Hou Shaoping [Beijing Institute of Neuroscience, Capital University of Medical Sciences, Beijing 100054 (China); Xu Qunyuan [Beijing Institute of Neuroscience, Capital University of Medical Sciences, Beijing 100054 (China); Spector, Myron [Tissue Engineering, VA Boston Healthcare System, Harvard Medical School, Boston, MA (United States); Cui Fuzhai [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2007-12-15

    The objective of the study was to determine the effects of a hyaluronic-acid-based (HA-based) hydrogel implant, carrying a polyclonal antibody to the Nogo-66 receptor (NgR), on adult rats that underwent middle cerebral artery occlusion (MCAO). Behavioral tests of a forelimb-reaching task suggested that the disabled function of the impaired forelimb in this stroke model was ameliorated by the implant to a certain extent. These behavioral findings were correlated with immunohistochemical results of investigating the distribution of NgR antibody, neurofilaments (NF) and neuron-specific class III {beta}-tubulin (TuJ1) in the brain sections. The porous hydrogel functioned as a scaffold to deliver the NgR antibody, support cell migration and development. In addition, it was found NF-positive and TuJ1-positive expressions were distributed in the implanted hydrogel. Collectively, the results demonstrate the promise of the HA hydrogel as a scaffold material and the delivery vehicle of the NgR antibody for the repair of defects and the support of neural regeneration in the brain.

  11. Medical students' and interns' interest in orthopedic surgery: the gender factor.

    Science.gov (United States)

    Schroeder, Joshua E; Zisk-Rony, Rachel Y; Liebergall, Meir; Tandeter, Howard; Kaplan, Leon; Weiss, Yoram G; Weissman, Charles

    2014-01-01

    There is an extremely small proportion of female medical students choosing to specialize in orthopedic surgery. The aim of the study was to assess medical students' and interns' interests and perceptions of orthopedic surgery and explore why women are not interested in orthopedic surgery. Questionnaires were distributed to final-year medical students and interns assessing their interests and perception of orthopedic surgery. Final-year medical students and interns. Responses were obtained from 317 students and 199 interns. Among the medical students, 15% were interested in orthopedic surgery, but only 2% were women. Both male and female students perceived orthopedics as an "action"-packed, procedure-based profession, providing instant gratification, time in the operating room, high income, and the option for private practice. Female medical students considered it boring. Among interns, 11% were interested in orthopedic surgery; however, only 2% were women. When compared with the interns who were not interested in orthopedic surgery, a greater number of the interns interested in orthopedic surgery rated time with family and a procedure-intensive profession as important. Female students and interns were also interested in other surgical fields. The increasing majority of women among medical students will reshape the future of physician workforce by dictating changes in workforce participation, working conditions, and intercollegial relationships. Orthopedic surgery will need to adapt to these realities. Published by Elsevier Inc.

  12. Orthopedic Implant Value Drivers: A Qualitative Survey Study of Hospital Purchasing Administrators.

    Science.gov (United States)

    Li, Chuan Silvia; Vannabouathong, Christopher; Sprague, Sheila; Bhandari, Mohit

    2015-01-01

    Osteoarthritis (OA) is a chronic, degenerative disease that is highly prevalent in the population, yet the factors that affect purchasing decisions related to this condition are poorly understood. A questionnaire was developed and administered to hospital executives across North America to determine the factors that affect purchasing decisions related to OA. Thirty-four individuals participated in the survey. Clinical evidence and cost effectiveness were deemed to be the most important factors in the process of making purchasing decisions. The most important considerations for adopting new technology were whether there was sufficient evidence in the literature, followed by thoughts of key opinion leaders, and cost of intervention/device. Ongoing research is still needed, but the current study allowed us to identify some trends in the data, providing new insight on how hospital purchasing decisions are made, which could have an immediate impact on those currently involved with making these decisions.

  13. Combustion synthesis of CoCrMo orthopedic implant alloys: microstructure and properties

    International Nuclear Information System (INIS)

    Li, Bingyun; Mukasyan, Alexander; Varma, Arvind

    2003-01-01

    Because of their excellent properties, such as corrosion resistance, fatigue strength and biocompatibility, cobalt-based alloys are widely used in total hip and knee replacements, dental devices and support structures for heart valves. In this work, CoCrMo alloys were synthesized using a novel method based on combustion synthesis (CS), an advanced technique to produce a wide variety of materials including alloys and near-net shape articles. This method possesses several advantages over conventional processes, such as low energy requirements, short processing times and simple equipment. The evaluated material properties included density and yield measurements, composition and microstructure analysis, hardness, friction and tensile tests. It was shown that microstructure of CS-material is finer and more uniform as compared to the conventional standard. It was also found that among various additives, Cr 3 C 2 is the most effective one for increasing material hardness. In addition, synthesized CoCrMo alloys exhibited good friction and mechanical properties. (orig.)

  14. Antimicrobial peptides for topical treatment of osteomyelitis and prevention of implant related infections in orthopedics

    Czech Academy of Sciences Publication Activity Database

    Čeřovský, Václav; Nešuta, Ondřej; Dudková, Vlasta; Melicherčík, P.

    2016-01-01

    Roč. 22, Suppl S2 (2016), S157-S158 ISSN 1075-2617. [European Peptide Symposium /34./ and International Peptide Symposium /8./. 04.09.2016-09.09.2016, Leipzig] Institutional support: RVO:61388963 Keywords : antimicrobial peptides * osteomyelitis Subject RIV: CE - Biochemistry

  15. A novel tribological study on DLC-coated micro-dimpled orthopedics implant interface.

    Science.gov (United States)

    Choudhury, Dipankar; Urban, Filip; Vrbka, Martin; Hartl, Martin; Krupka, Ivan

    2015-05-01

    This study investigates a tribological performance of diamond like carbon (DLC) coated micro dimpled prosthesis heads against ceramic cups in a novel pendulum hip joint simulator. The simulator enables determining friction coefficient and viscous effects of a concave shaped specimen interface (conformal contact). Two types of DLC such as hydrogenated amorphous carbon (a-C:H) and tetrahedral amorphous carbon (Ta-C) and one set of micro dimple (diameter of 300µm, depth of 70µm, and pitch of 900µm) were fabricated on metallic prosthesis heads. The experiment results reveal a significant friction coefficient reduction to the 'dimpled a-C:H/ceramic' prosthesis compared to a 'Metal (CoCr)/ceramic' prosthesis because of their improved material and surface properties and viscous effect. The post-experiment surface analysis displays that the dimpled a-C:H yielded a minor change in the surface roughness, and generated a larger sizes of wear debris (40-200nm sized, equivalent diameter), a size which could be certainly stored in the dimple, thus likely to reducing their possible third body abrasive wear rate. Thus, dimpled a:C-H can be used as a 'metal on ceramic hip joint interface', whereas the simulator can be utilized as an advanced bio-tribometer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. ZK30-bioactive glass composites for orthopedic applications: A comparative study on fabrication method and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Huan, Z.G.; Leeflang, M.A. [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands); Zhou, J., E-mail: j.zhou@tudelft.nl [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands); Duszczyk, J. [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Biodegradable Mg-bioglass composites were made using casting; powder metallurgy. Black-Right-Pointing-Pointer Bioglass powder retained its composition and morphology. Black-Right-Pointing-Pointer Accelerated deposition of Ca; P ions on composites occurred due to bioglass. Black-Right-Pointing-Pointer Mg-bioglass composites made from powders had reduced degradation rates. Black-Right-Pointing-Pointer Powder metallurgy appeared to be better for making biodegradable composites. - Abstract: Previous in vivo studies on biodegradable magnesium alloys for orthopedic implant applications showed the need to improve early-stage bioactivity. Introducing bioactive particles into a magnesium alloy to form a metal matrix composite (MMC) represents an effective way to enhance the bioactivity of the alloy. In this study, composites with the ZK30 alloy as the matrix and the 45S5 bioactive glass (BG) as the reinforcement phase were fabricated using a semi-solid casting (SSC) method and a powder metallurgy (P/M) method. The SSC and P/M biocomposites with the same weight percents of bioactive glass particles were compared. Optical microscopy showed homogeneously dispered BG particles in the SSC and P/M composites. SEM and EDX analyses confirmed the retention of the morphological characteristics and composition of BG particles in the composites. However, the SSC composites exhibited micro-porous structures, while the P/M composites had nearly fully densified structures. As compared with the ZK30 matrix, the SSC composites exhibited significantly higher degradation rates, while the P/M composites possessed lower degradation rates. On the surface of all the composites, accelerated deposition of Ca and P ions occurred during immersion in the cell culture medium, indicating an improved surface bioactivity of the composites. The P/M method was found to be advantageous over the SSC method and could yield magnesium-matrix composites with enhanced

  17. Nanoscale Topography on Black Titanium Imparts Multi-biofunctional Properties for Orthopedic Applications

    Science.gov (United States)

    Hasan, Jafar; Jain, Shubham; Chatterjee, Kaushik

    2017-01-01

    We have developed a chlorine based reactive ion etching process to yield randomly oriented anisotropic nanostructures that render the titanium metal surface ‘black’ similar to that of black silicon. The surface appears black due to the nanostructures in contrast to the conventional shiny surface of titanium. The nanostructures were found to kill bacteria on contact by mechanically rupturing the cells as has been observed previously on wings of certain insects. The etching was optimized to yield nanostructures of ≈1 μm height for maximal bactericidal efficiency without compromising cytocompatibility. Within 4 hours of contact with the black titanium surface, 95% ± 5% of E. coli, 98% ± 2% of P. aeruginosa, 92% ± 5% of M. smegmatis and 22% ± 8% of S. aureus cells that had attached were killed. The killing efficiency for the S. aureus increased to 76% ± 4% when the cells were allowed to adhere up to 24 hours. The black titanium supported the attachment and proliferation of human mesenchymal stem cells and augmented osteogenic lineage commitment in vitro. Thus, the bioinspired nanostructures on black titanium impart multi-biofunctional properties toward engineering the next-generation biomaterials for orthopedic implants.

  18. Antibiotic prophylaxis in orthopedic surgeries: the results of an implemented protocol

    Directory of Open Access Journals (Sweden)

    Raquel Queiroz

    Full Text Available Though the basic principles of antibiotic prophylaxis have been well established, there is still considerable incorrect usage, including how much is prescribed and especially in the duration of treatment, which is generally superior to what is indicated. The adequate use of these drugs contributes towards decreasing the time of internment of the patient, prevents surgical site infection (SSI, decreasing the development of resistant microorganisms, and towards reduced costs for the hospital pharmacy. A protocol for the use of antibiotic prophylaxis in the Orthopedics and Traumatology Service of the Hospital do Servidor Público Estadual de São Paulo was developed. The objectives of the study were to promote rational antibiotic surgical prophylaxis, through the implantation of a protocol for the use of these drugs in a surgical unit, with the direct contribution of a druggist in collaboration with the Infection Control Committee, to evaluate the adhesion of the health team to the protocol during three distinct periods (daily pre-protocol, early post-protocol and late post-protocol and to define the consumption of antimicrobials used, measured as daily defined dose.

  19. Hip Implant Systems

    Science.gov (United States)

    ... Implants and Prosthetics Metal-on-Metal Hip Implants Hip Implants Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Hip implants are medical devices intended to restore mobility ...

  20. Breast reconstruction - implants

    Science.gov (United States)

    Breast implants surgery; Mastectomy - breast reconstruction with implants; Breast cancer - breast reconstruction with implants ... harder to find a tumor if your breast cancer comes back. Getting breast implants does not take as long as breast reconstruction ...

  1. A computational method for comparing the behavior and possible failure of prosthetic implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.; Hollerbach, K.; Perfect, S.; Underhill, K.

    1995-05-01

    Prosthetic joint implants currently in use exhibit high Realistic computer modeling of prosthetic implants provides an opportunity for orthopedic biomechanics researchers and physicians to understand possible in vivo failure modes, without having to resort to lengthy and costly clinical trials. The research presented here is part of a larger effort to develop realistic models of implanted joint prostheses. The example used here is the thumb carpo-metacarpal (cmc) joint. The work, however, can be applied to any other human joints for which prosthetic implants have been designed. Preliminary results of prosthetic joint loading, without surrounding human tissue (i.e., simulating conditions under which the prosthetic joint has not yet been implanted into the human joint), are presented, based on a three-dimensional, nonlinear finite element analysis of three different joint implant designs.

  2. Nanotubular surface modification of metallic implants via electrochemical anodization technique.

    Science.gov (United States)

    Wang, Lu-Ning; Jin, Ming; Zheng, Yudong; Guan, Yueping; Lu, Xin; Luo, Jing-Li

    2014-01-01

    Due to increased awareness and interest in the biomedical implant field as a result of an aging population, research in the field of implantable devices has grown rapidly in the last few decades. Among the biomedical implants, metallic implant materials have been widely used to replace disordered bony tissues in orthopedic and orthodontic surgeries. The clinical success of implants is closely related to their early osseointegration (ie, the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant), which relies heavily on the surface condition of the implant. Electrochemical techniques for modifying biomedical implants are relatively simple, cost-effective, and appropriate for implants with complex shapes. Recently, metal oxide nanotubular arrays via electrochemical anodization have become an attractive technique to build up on metallic implants to enhance the biocompatibility and bioactivity. This article will thoroughly review the relevance of electrochemical anodization techniques for the modification of metallic implant surfaces in nanoscale, and cover the electrochemical anodization techniques used in the development of the types of nanotubular/nanoporous modification achievable via electrochemical approaches, which hold tremendous potential for bio-implant applications. In vitro and in vivo studies using metallic oxide nanotubes are also presented, revealing the potential of nanotubes in biomedical applications. Finally, an outlook of future growth of research in metallic oxide nanotubular arrays is provided. This article will therefore provide researchers with an in-depth understanding of electrochemical anodization modification and provide guidance regarding the design and tuning of new materials to achieve a desired performance and reliable biocompatibility.

  3. Antibacterial iodine-supported titanium implants.

    Science.gov (United States)

    Shirai, T; Shimizu, T; Ohtani, K; Zen, Y; Takaya, M; Tsuchiya, H

    2011-04-01

    Deep infection remains a serious complication in orthopedic implant surgery. In order to reduce the incidence of implant-associated infections, several biomaterial surface treatments have been proposed. This study focused on evaluating the antibacterial activity of iodine-supported titanium (Ti-I(2)) and its impact on post-implant infection, as well as determining the potential suitability of Ti-I(2) as a biomaterial. External fixation pins were used in this experiment as trial implants because of the ease of making the septic models. The antibacterial activity of the metal was measured using a modification of the Japanese Industrial Standards method. Activity was evaluated by exposing the implants to Staphylococcus aureus or Escherichia coli and comparing reaction of pathogens to Ti-I(2) vs. stainless steel and titanium controls. Ti-I(2) clearly inhibited bacterial colonization more than the control metals. In addition, cytocompatibility was assessed by counting the number of colonies that formed on the metals. The three metals showed the same amount of fibroblast colony formation. Japanese white rabbits were used as an in vivo model. Three pins were inserted into both femora of six rabbits for histological analysis. Pin sites were inspected and graded for infection and inflammation. Fewer signs of infection and inflammatory changes were observed in conjunction with the Ti-I(2) pins. Furthermore, osteoconductivity of the implant was evaluated with osteoid formation surface of the pin. Consecutive bone formation was observed around the Ti-I(2) and titanium pins, while little osteoid formation was found around the stainless steel pins. These findings suggest that Ti-I(2) has antimicrobial activity and exhibits cytocompatibility. Therefore, Ti-I(2) substantially reduces the incidence of implant infection and shows particular promise as a biomaterial. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. The Effect of Price on Surgeons' Choice of Implants: A Randomized Controlled Survey.

    Science.gov (United States)

    Wasterlain, Amy S; Melamed, Eitan; Bello, Ricardo; Karia, Raj; Capo, John T

    2017-08-01

    Surgical costs are under scrutiny and surgeons are being held increasingly responsible for cost containment. In some instances, implants are the largest component of total procedure cost, yet previous studies reveal that surgeons' knowledge of implant prices is poor. Our study aims to (1) understand drivers behind implant selection and (2) assess whether educating surgeons about implant costs affects implant selection. We surveyed 226 orthopedic surgeons across 6 continents. The survey presented 8 clinical cases of upper extremity fractures with history, radiographs, and implant options. Surgeons were randomized to receive either a version with each implant's average selling price ("price-aware" group), or a version without prices ("price-naïve" group). Surgeons selected a surgical implant and ranked factors affecting implant choice. Descriptive statistics and univariate, multivariable, and subgroup analyses were performed. For cases offering implants within the same class (eg, volar locking plates), price-awareness reduced implant cost by 9% to 11%. When offered different models of distal radius volar locking plates, 25% of price-naïve surgeons selected the most expensive plate compared with only 7% of price-aware surgeons. For cases offering different classes of implants (eg, plate vs external fixator), there was no difference in implant choice between price-aware and price-naïve surgeons. Familiarity with the implant was the most common reason for choosing an implant in both groups (35% vs 46%). Price-aware surgeons were more likely to rank cost as a factor (29% vs 21%). Price awareness significantly influences surgeons' choice of a specific model within the same implant class. Merely including prices with a list of implants leads surgeons to select less expensive implants. This implies that an untapped opportunity exists to reduce surgical expenditures simply by enhancing surgeons' cost awareness. Economic/Decision Analyses I. Copyright © 2017 American

  5. Deproteinized Bovine Bone Mineral or Autologous Bone at Dehiscence Type Defects at Implants Installed Immediately into Extraction Sockets: An Experimental Study in Dogs.

    Science.gov (United States)

    Pereira, Flavia Priscila; De Santis, Enzo; Hochuli-Vieira, Eduardo; de Souza Faco, Eduardo F; Pantani, Fabio; Salata, Luiz A; Botticelli, Daniele

    2016-06-01

    The aim of this study was to evaluate bone regeneration at surgically created dehiscence buccal defects at implants placed immediately into extraction sockets (IPIES) of small dimensions filled with autogenous bone or deproteinized bovine bone mineral (DBBM) associated with a collagen membrane. Eight Labrador dogs were used and implants were placed immediately into the extraction sockets of the second premolar. The buccal wall was subsequently removed to create a standardized defect, 4 mm wide coronally, 2 mm wide apically, and 6 mm high. Autogenous bone particles (AB) or DBBM granules were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membrane and a non-submerged healing was allowed. After 4 months, the animals were euthanized and bone blocks harvested and processed for histomorphometric analysis. The bony crest at the buccal aspect (C) was located 2.3 ± 0.8 mm and 1.7 ± 0.7 mm apically to the implant shoulder (IS) at the AB and DBBM sites, respectively. The coronal levels of osseointegration at the buccal aspect (B) were located 2.7 ± 0.7 mm and 2.2 ± 1.0 mm apically to IS at the AB and DBBM sites, respectively. At the AB sites, the peri-implant mucosa was located 4.3 ± 0.9 mm, 4.7 ± 0.9 mm, and 2.0 ± 1.6 mm coronally to C, B, and IS, respectively. The corresponding values at the DBBM sites were 4.3 ± 0.6 mm, 4.8 ± 0.6 mm, and 2.5 ± 0.8 mm, respectively. No statistically significant differences were found. The treatment of surgically created buccal defects at IPIES sites using Bio-Oss® (Geistlich Biomaterials, Wolhusen, LU, Switzerland) or autogenous bone, concomitantly with a collagen membrane, engenders bone regeneration to a similar extent after 4 months of healing. © 2015 Wiley Periodicals, Inc.

  6. Emprego experimental da poliuretana derivada de óleo de mamona (Ricinus communis L: em implantes lamelares, interlamelares e penetrantes na córnea de coelhos

    Directory of Open Access Journals (Sweden)

    Adriana Morales

    2005-02-01

    Full Text Available Há muito que se estudam métodos e materiais reparadores de córnea, em busca de uma melhor reposição tecidual e, principalmente, manutenção ou recuperação da visão. A pesquisa de novos biomateriais tem permitido produzir próteses capazes de desempenhar a função requerida, sem reação importante. Conhecendo-se os bons resultados obtidos com a utilização da poliuretana vegetal derivada de óleo de mamona (Ricinus communis L. em vários procedimentos, estudou-se sua implantação, em forma de membrana, na córnea, objetivando oferecer novo material para a reparação de lesões corneanas e a confecção de ceratopróteses biologicamente inertes. Utilizaram-se 28 coelhos, divididos em dois grupos (G1 e G2 e estes em subgrupos para avaliações de implantes lamelares e interlamelares aos 2, 7, 15, 30, 60 e 120 dias, e implantes penetrantes, aos 2, 7, 15, 30 e 60 dias de pós-operatório. Estudaram-se parâmetros como neovascularização, inflamação, transparência de córneas e implantes, bem como a aderência e viabilidade destes, através de exames oculares, e histopatológicos à microscopia óptica. Observou-se reação inflamatória branda em todos os períodos. Os implantes lamelares e penetrantes permitiram reparação da córnea e manutenção da integridade dos globos oculares, embora sofressem deiscência entre 5 e 28 dias de pós-operatório. Concluiu-se pela boa biocompatibilidade do material e pela possibilidade de empregar-se o polímero na reparação corneana e, possivelmente, em ceratopróteses.

  7. Modified cementless total coxofemoral prosthesis: development, implantation and clinical evaluation

    Directory of Open Access Journals (Sweden)

    S.A. Arias

    2013-12-01

    Full Text Available The aim of this study was to modify canine coxofemoral prostheses and the clinical evaluation of the implantation. Fifteen canine hips and femora of cadavers were used in order to study the surface points of modification in prostheses and develop a perforation guide. Femoral stems and acetabular components were perforated and coated with biphasic calcium phosphate layer. Twelve young adult male mongrel dogs were implanted with coxofemoral prostheses. Six were operated upon and implanted with cemented canine modular hip prostheses, establishing the control group. The remaining six were implanted with a novel design of cementless porous tricalcic phosphate-hydroxyapatite coated hip prostheses. Clinical and orthopedic performance, complications, and thigh muscular hypotrophy were assessed up to the 120th post-operatory day. After 120 days, animals with cementless prostheses had similar clinical and orthopedic performance compared to the cemented group despite the increased pain thigh hypotrophy. Animals that underwent cementless hip prosthesis evidenced more pain, compared to animals with cemented hip prosthesis that required longer recuperation time. No luxations, two fractures and two isquiatic neurapraxies were identified in the course of the study. Using both the cemented and the bioactive coated cementless model were suitable to dogs, showing clinical satisfactory results. Osseointegration and biological fixation were observed in the animals with the modified cementless hip prosthesis.

  8. Analysis on Risk Factors of Nosocomial Infection in Orthopedic Patients and Research on Nursing Strategies

    Directory of Open Access Journals (Sweden)

    Guo Zhitao

    2016-03-01

    Full Text Available Orthopedic patients mostly comprise traumatic patients and elderly or sick individuals. More patients with emergency surgery suffer from open wounds and serious pollution, and operation time is relatively long. Thus, orthopedic patients with surgical incision infection account for a large proportion of incidence of hospital infection. Orthopedic patients are also bedridden for long periods, and they receive poor bone tissue blood supply. In surgical incision infections, mild cases suffer from delayed wound healing, whereas severe cases can form osteomyelitis. This study reviews progress of research on risk factors of nosocomial infection among orthopedic patients in recent years.

  9. Trends in the orthopedic job market and the importance of fellowship subspecialty training.

    Science.gov (United States)

    Morrell, Nathan T; Mercer, Deana M; Moneim, Moheb S

    2012-04-01

    Previous studies have examined possible incentives for pursuing orthopedic fellowship training, but we are unaware of previously published studies reporting the trends in the orthopedic job market since the acceptance of certain criteria for fellowship programs by the Accreditation Council for Graduate Medical Education (ACGME) in 1985. We hypothesized that, since the initiation of accredited postresidency fellowship programs, job opportunities for fellowship-trained orthopedic surgeons have increased and job opportunities for nonfellowship-trained orthopedic surgeons have decreased. We reviewed the job advertisements printed in the Journal of Bone and Joint Surgery, American Volume, for the years 1984, 1994, 2004, and 2009. We categorized the job opportunities as available for either a general (nonfellowship-trained) orthopedic surgeon or a fellowship-trained orthopedic surgeon. Based on the advertisements posted in the Journal of Bone and Joint Surgery, American Volume, a trend exists in the orthopedic job market toward seeking fellowship-trained orthopedic surgeons. In the years 1984, 1994, 2004, and 2009, the percentage of job opportunities seeking fellowship-trained orthopedic surgeons was 16.7% (95% confidence interval [CI], 13.1%-20.3%), 40.6% (95% CI, 38.1%-43.1%), 52.2% (95% CI, 48.5%-55.9%), and 68.2% (95% CI, 65.0%-71.4%), respectively. These differences were statistically significant (analysis of variance, Ptraining is thus a worthwhile endeavor. Copyright 2012, SLACK Incorporated.

  10. Effects of substitute coated with hyaluronic acid or poly-lactic acid on implant fixation. Experimental study in ovariectomized and glucocorticoid treated sheep

    DEFF Research Database (Denmark)

    Andreasen, Christina M; Ding, Ming; Andersen, Thomas L

    2018-01-01

    Investigated in healthy animal models, hyaluronic acid (HyA) and poly-D,L -lactic acid (PDLLA) demonstrate osteoconductive properties when coated onto hydroxyapatite (HA) and β-tricalcium phosphate (βTCP) scaffolds. In this study, we examined the efficacy of HA/βTCP granules coated with HyA or PD...... formation, HyA and PDDLA are indeed considered valuable as new coating materials for composite ceramics when tested in a sheep model - even in bones of a compromised quality.......Investigated in healthy animal models, hyaluronic acid (HyA) and poly-D,L -lactic acid (PDLLA) demonstrate osteoconductive properties when coated onto hydroxyapatite (HA) and β-tricalcium phosphate (βTCP) scaffolds. In this study, we examined the efficacy of HA/βTCP granules coated with Hy...... allograft obtained from a healthy donor sheep (control), pure HA/βTCP, HA/βTCP-HyA or HA/βTCP-PDLLA. After 12 weeks, the bone formation adjacent to the implant surface was evaluated by histology and histomorphometry, while the implant fixation was measured by a push-out test. The investigation showed a bone...

  11. The organizational and financial viability of an orthopedic trauma service.

    Science.gov (United States)

    Harris, Mitchel B; Cayen, Barry

    2009-12-01

    This study was designed to explore the effect of establishing an Orthopedic Trauma Service (OTS) on departmental revenue within an academic orthopedic department. The effect of the OTS on physician and resident perceptions of job satisfaction, education, and quality of patient care were also evaluated. A proforma financial analysis was undertaken using an optimization model to predict the potential financial performance of an OTS before its implementation. Financial data were then collected prospectively for the first year of the OTS and compared with the preceding year's financial data. All residents and faculty in the department completed visual analog scale surveys after the formation of the service. While maintaining a fixed amount of work production (work relative value units [WRVUs]) per year, our model predicted an $111,000 increase in departmental charges as a result of a shift in the elective case mix. After implementation of the OTS, elective charges/WRVU increased by 7.4% while trauma charges/WRVU increased by 2.6%. This, combined with a minor increase in departmental work volume (115,661 WRVUs pre-OTS vs. 117,577 WRVUs post-OTS) and an improvement in collections/charge (47-48%), yielded a departmental collection increase of 11% ($1.1 million). Resident and faculty job satisfaction improved, as did the perception of the quality of trauma care that was being provided. The organization and implementation of an OTS within an academic orthopedic department can lead to an improved professional experience for residents and faculty, the perception of improved patient care for the trauma patient, and an increase in departmental revenue.

  12. [Femoral artery pseudoaneurysms encountered in orthopedics and traumatology].

    Science.gov (United States)

    Raherinantenaina, F; Rajaonanahary, T M A; Rakoto Ratsimba, H N

    2015-12-01

    Most published articles regarding orthopedic- and trauma-related femoral artery pseudoaneurysms (FAPs) are case reports in English. Reported cases are often associated with a literature review but actually provide little robust data. We wanted to summarize the current knowledge on diagnostic and therapeutic features of these FAPs. A new case of superficial FAP is described followed by a review of the literature. A bibliographic search was performed online (PubMed, ScinceDirect) from 1964 to 2015 using the descriptors "traumatic femoral pseudoaneurysm, orthopedic surgery, osteochondroma". A total of 64 cases of FAPs was analyzed. There were 50 men with an average age of 40.72±26.45 years old. The most common clinical presentation was painful swelling (34%). Arteriography was the commonest radiological investigation used (63%). The main etiologies were orthopedic injuries (47%), surgery of the upper thigh (30%) and femoral osteochondromas (23%). Arterial injuries included superficial femoral (47%) and profunda femoris artery (50%). The treatment was open surgery (56%) or endovascular repair (36%). Deep femoral artery and its branches were embolized (47%) or ligated (38%). Endovascular stenting was performed in 30% of posttraumatic FAPs. All FAPs relating to osteochondromas were repaired surgically. Postoperative courses were uneventful in 95% of patients. Endovascular embolization is preferred in management of postsurgical FAPs which have usually involved the deep femoral artery. Endovascular stenting graft may be proposed for posttraumatic FAPs, for which the superficial femoral trunk is the most often involved vessel. Surgical repair should be performed when endovascular stenting graft is not feasible. Surgical repair is mandatory for all FAPs secondary to traumatic exostoses. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. E-learning in orthopedic surgery training: A systematic review.

    Science.gov (United States)

    Tarpada, Sandip P; Morris, Matthew T; Burton, Denver A

    2016-12-01

    E-learning is the use of internet-based resources in education. In the field of surgical education, this definition includes the use of virtual patient cases, digital modeling, online tutorials, as well as video recordings of surgical procedures and lectures. In recent years, e-learning has increasingly been considered a viable alternative to traditional teaching within a number of surgical fields. Here we present (1) a systematic review of literature assessing the efficacy of e-learning modules for orthopedic education and (2) a discussion of their relevance. A systematic search of PubMed, Embase, Web of Science, and the Cochrane Library was conducted according to the guidelines defined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA). The search yielded a total of 255 non-duplicate citations that were screened using predetermined inclusion/exclusion criteria. A total of 9 full text articles met inclusion criteria, which included the use of an objective outcome measure to evaluate an orthopedic e-learning module. Six studies assessed knowledge using a multiple-choice test and 4 assessed skills using a clinical exam. All studies showed positive score improvement pre- to post-intervention, and a majority showed greater score improvement than standard teaching methods in both knowledge (4/6 studies) and clinical skills (3/4 studies). E-learning represents an effective supplement or even alternative to standard teaching techniques within orthopedic education for both medical students and residents. Future work should focus on validating specific e-learning programs using standardized outcome measures and assessing long-term knowledge retention using e-learning platforms.

  14. Device-length changes and implant function following surgical implantation of the KineSpring in cadaver knees

    Directory of Open Access Journals (Sweden)

    McNicholas MJ

    2015-01-01

    Full Text Available Michael J McNicholas,1 Stefan M Gabriel,2 Anton G Clifford,2 Evelyne M Hasler2 1Aintree University Hospital, Teaching Hospital, Major Trauma Centre, NHS Foundation Trust, Liverpool, UK; 2Moximed, Hayward, CA, USA Introduction: The KineSpring implant system has been shown to provide load reductions at the medial compartment of the knee, and has demonstrated clinical success in reducing pain and increasing function in patients with medial knee osteoarthritis. These results depend on the ability of the KineSpring to rotate, lengthen, and shorten to accommodate knee motions, and in response to knee position and loading. Purpose: The present study was undertaken to determine length changes of the implanted KineSpring in response to a range of knee positions, external knee loads, and placements by different orthopedic surgeons. Materials and methods: KineSpring system components were implanted in ten cadaver leg specimens by ten orthopedic surgeons, and absorber-length changes were measured under combined loading and in different positions of the knee. Results and conclusion: Spring compression consistent with knee-load reduction, and device lengthening and shortening to accommodate knee loads and motions were seen. These confirm the functionality of the KineSpring when implanted medially to the knee. Keywords: KineSpring, knee, function, preservation, offloading, osteoarthritis

  15. Validity of subjective smoking status in orthopedic patients

    Directory of Open Access Journals (Sweden)

    Bender D

    2015-08-01

    Full Text Available Daniel Bender,* Patrick Haubruck,* Sonja Boxriker, Sebastian Korff, Gerhard Schmidmaier, Arash Moghaddam Trauma and Reconstructive Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany *These authors contributed equally to this work Purpose: In this level 1 diagnostic study, we analyzed the validity of subjective smoking status and, as secondary research question, the smoking cessation adherence in orthopedic patients during a routine hospital stay of nonunion patients by measuring serum cotinine.  Methods: We included patients undergoing revision surgery due to nonunion of long bones. Patients were interviewed about their smoking status. Blood samples were taken from all the patients prior to surgery and for an additional 6 weeks following surgery. Serum levels of cotinine were measured, and coherence between subjective smoking status and objective cotinine analysis was evaluated.  Results: Between March 2012 and August 2014, we enrolled 136 patients. Six of the 26 “previous smokers” (23% and four of the 65 “nonsmokers” (6% had serum cotinine above cutoff levels. In self-labeled smokers, serum cotinine levels averaged at 2,367.4±14,885.9 ng/mL (with a median of 100 ng/mL, whereas in previous smokers the levels averaged at 4,270±19,619.4 ng/mL (with a median of 0 ng/mL and in the nonsmokers group the levels averaged at 12±53.9 ng/mL (with a median of 0.03 ng/mL. Overall, the subjective smoking status matched serum cotinine testing in 88% of the cases. Sensitivity was 79.6% and specificity was 93.1%. Ninety-one percent of the patients with preoperative positive serum values were still positive at follow-up.  Conclusion: In this study, we could show that subjective smoking status in orthopedic patients is predominantly reliable as validated by objective cotinine measurements; however, patients who declare themselves as “previous smokers” are at elevated risk

  16. Semuloparin for prevention of venous thromboembolism after major orthopedic surgery

    DEFF Research Database (Denmark)

    Lassen, M R; Fisher, W; Mouret, P

    2012-01-01

    BACKGROUND: Semuloparin is a novel ultra-low-molecular-weight heparin under development for venous thromboembolism (VTE) prevention in patients at increased risk, such as surgical and cancer patients. OBJECTIVES: Three Phase III studies compared semuloparin and enoxaparin after major orthopedic...... was to be performed between days 7 and 11. The primary efficacy endpoint was a composite of any deep vein thrombosis, non-fatal pulmonary embolism or all-cause death. Safety outcomes included major bleeding, clinically relevant non-major (CRNM) bleeding, and any clinically relevant bleeding (major bleeding plus CRNM...

  17. Influence of copper composition on mechanical properties of biodegradable material Mg-Zn-Cu for orthopedic application

    Science.gov (United States)

    Purniawan, A.; Maulidiah, H. M.; Purwaningsih, H.

    2018-04-01

    Implant is usually used as a treatment of bone fracture. At the moment, non-biodegradable implants is still widely employed in this application. Non-biodegradable implant requires re-surgery to retrieve implants that are installed in the body. It increase the cost and it is painful for the patient itself. In order to solve the problem, Mg-based biodegradable metals is developing so that the material will be compatible with body and gradually degrade in patient's body. However, magnesium has several disadvantages such as high degradation rates and low mechanical properties when compared to the mechanical properties of natural bone. Therefore, it is necessary to add elements into the magnesium alloy. In this research, copper (Cu) was alloyed in Mg alloy based biodegradable material. In addition, Cu is not only strengthening the structure but also for supporting element for the immune system, antibacterial and antifungal. The purpose of this research is to improve mechanical properties of Mg-based biodegradable material using Cu alloying. Powder metallurgy method was used to fabricate the device. The variation used in this research is the composition of Cu (0.5, 1, and 1.5% Cu). The porosity test was performed using apparent porosity test, compressive test and hardness test to know the mechanical properties of the alloy, and the weightless test to find out the material degradation rate. Based on the results can be conclude that Mg-Zn-Cu alloy material with 1% Cu composition is the most suitable specimen to be applied as a candidate for orthopedic devices material with hardness value is 393.6 MPa. Also obtained the value of the compressive test is 153 MPa.

  18. Effect of pore size on bone ingrowth into porous titanium implants fabricated by additive manufacturing: An in vivo experiment.

    Science.gov (United States)

    Taniguchi, Naoya; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Sasaki, Kiyoyuki; Otsuki, Bungo; Nakamura, Takashi; Matsushita, Tomiharu; Kokubo, Tadashi; Matsuda, Shuichi

    2016-02-01

    Selective laser melting (SLM) is an additive manufacturing technique with the ability to produce metallic scaffolds with accurately controlled pore size, porosity, and interconnectivity for orthopedic applications. However, the optimal pore structure of porous titanium manufactured by SLM remains unclear. In this study, we evaluated the effect of pore size with constant porosity on in vivo bone ingrowth in rabbits into porous titanium implants manufactured by SLM. Three porous titanium implants (with an intended porosity of 65% and pore sizes of 300, 600, and 900μm, designated the P300, P600, and P900 implants, respectively) were manufactured by SLM. A diamond lattice was adapted as the basic structure. Their porous structures were evaluated and verified using microfocus X-ray computed tomography. Their bone-implant fixation ability was evaluated by their implantation as porous-surfaced titanium plates into the cortical bone of the rabbit tibia. Bone ingrowth was evaluated by their implantation as cylindrical porous titanium implants into the cancellous bone of the rabbit femur for 2, 4, and 8weeks. The average pore sizes of the P300, P600, and P900 implants were 309, 632, and 956μm, respectively. The P600 implant demonstrated a significantly higher fixation ability at 2weeks than the other implants. After 4weeks, all models had sufficiently high fixation ability in a detaching test. Bone ingrowth into the P300 implant was lower than into the other implants at 4weeks. Because of its appropriate mechanical strength, high fixation ability, and rapid bone ingrowth, our results indicate that the pore structure of the P600 implant is a suitable porous structure for orthopedic implants manufactured by SLM. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Comparison between mixed and laminar airflow systems in operating rooms and the influence of human factors: experiences from a Swedish orthopedic center.

    Science.gov (United States)

    Erichsen Andersson, Annette; Petzold, Max; Bergh, Ingrid; Karlsson, Jón; Eriksson, Bengt I; Nilsson, Kerstin

    2014-06-01

    The importance of laminar airflow systems in operating rooms as protection from surgical site infections has been questioned. The aim of our study was to explore the differences in air contamination rates between displacement ventilation and laminar airflow systems during planned and acute orthopedic implant surgery. A second aim was to compare the influence of the number of people present, the reasons for traffic flow, and the door-opening rates between the 2 systems. Active air sampling and observations were made during 63 orthopedic implant operations. The laminar airflow system resulted in a reduction of 89% in colony forming units in comparison with the displacement system (P operating rooms offer high-quality air during surgery, with very low levels of colony forming units close to the surgical wound. The continuous maintenance of laminar air flow and other technical systems are crucial, because minor failures in complex systems like those in operating rooms can result in a detrimental effect on air quality and jeopardize the safety of patients. The technical ventilation solutions are important, but they do not guarantee clean air, because many other factors, such as the organization of the work and staff behavior, influence air cleanliness. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  20. Estudo experimental do implante transcateter de prótese valvada autoexpansível na via de saída do ventrículo direito em porcos Transcatheter implantation of self-expandable valved prosthesis in outlet right ventricle an experimental study in pigs

    Directory of Open Access Journals (Sweden)

    José Cícero Stocco Guilhen

    2011-09-01

    Full Text Available INTRODUÇÃO: Nos pacientes portadores de cardiopatias congênitas que foram submetidos à valvotomia pulmonar ou cirurgias de ampliação com o uso do anel da válvula pulmonar, a insuficiência ou estenose pulmonar residual pode acarretar falência cardíaca direita com deterioração clínica. Essas crianças necessitam de múltiplas intervenções ao longo de suas vidas, que impõem uma elevada taxa de morbidade e mortalidade. OBJETIVO: Desenvolvimento de uma técnica menos invasiva para implante de uma prótese valvada através do ventrículo direito. MÉTODOS: A prótese valvada consiste em um anel metálico construído com nitinol autoexpansível, revestida de poliéster, onde três cúspides de pericárdio bovino foram montadas. Doze porcos foram utilizados para a realização dos implantes. Foi realizado controle ecocardiográfico imediatamente após o implante e com uma, quatro, oito e 12 semanas. RESULTADOS: Um animal apresentou refluxo de grau moderado a importante e outros três refluxo de grau leve. Os gradientes transvalvares medidos antes do implante variavam entre 3 a 6 mmHg, sendo que, logo após o implante, houve aumento dos gradientes que variaram de 7 a 45 mmHg. Houve queda desses gradientes, sendo que em apenas quatro dos 12 animais os gradientes estavam acima de 20 mmHg. Em seis animais, ocorreu a formação de trombo na prótese, sendo esta a complicação mais frequente. CONCLUSÃO: Esses achados evidenciam a necessidade da realização de estudos com a utilização de anticoagulantes e ou antiagregantes plaquetários na tentativa de diminuir esse evento. O estudo pretende apresentar subsídios para o início do emprego de próteses valvares que poderiam ser implantadas através de técnicas menos invasivasINTRODUCTION: Patients with congenital heart disease who underwent pulmonary valvotomy or surgery to open the pulmonary valve ring are prone to develop residual pulmonary insufficiency or stenosis that may lead to

  1. Developments in ambulatory surgery in orthopedics in France in 2016.

    Science.gov (United States)

    Hulet, C; Rochcongar, G; Court, C

    2017-02-01

    Under the new categorization introduced by the Health Authorities, ambulatory surgery (AS) in France now accounts for 50% of procedures, taking all surgical specialties together. The replacement of full hospital admission by AS is now well established and recognized. Health-care centers have learned, in coordination with the medico-surgical and paramedical teams, how to set up AS units and the corresponding clinical pathways. There is no single model handed down from above. The authorities have encouraged these developments, partly by regulations but also by means of financial incentives. Patient eligibility and psychosocial criteria are crucial determining factors for the success of the AS strategy. The surgeons involved are strongly committed. Feedback from many orthopedic subspecialties (shoulder, foot, knee, spine, hand, large joints, emergency and pediatric surgery) testify to the rise of AS, which now accounts for 41% of all orthopedic procedures. Questions remain, however, concerning the role of the GP in the continuity of care, the role of innovation and teaching, the creation of new jobs, and the attractiveness of AS for surgeons. More than ever, it is the patient who is "ambulatory", within an organized structure in which surgical technique and pain management are well controlled. Not all patients can be eligible, but the AS concept is becoming standard, and overnight stay will become a matter for medical and surgical prescription. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. Indications for CT, MRI, and scintiscanning in orthopedics and traumatology

    International Nuclear Information System (INIS)

    Hahn, K.; Heine, J.; Thelen, T.

    1994-01-01

    Successful treatment of disease of the locomotor system requires as exact as possible diagnostic evaluation of the individual conditions, and this in turn can be achieved only by collaborative efforts of experts from a variety of subject fields. The book in hand is the result of such a collaborative approach, presenting the knowledge and experience of orthopedic surgeons, radiologists, and nuclear medicine experts who establish an order of priority and diagnostic value of computed tomography, magnetic resonance imaging, and various scintiscanning methods with respect to the diagnosis of orthopedic lesions. On the basis of this order of priority, specific recommendations are presented and explained for the best possible diagnostic procedure for evaluation of the various cases. The material is arranged into the following chapters: Examination modalities, techniques and cost - Inflammatory lesions of the locomotive system - Specific traumatology - Tumors of the locomotive system - Lesions of the hip joint - Lesions of the knee joint - Lesions of the spine -Lesions of the shoulder. (orig./MG) [de

  3. Intraoperative Secondary Insults During Orthopedic Surgery in Traumatic Brain Injury.

    Science.gov (United States)

    Algarra, Nelson N; Lele, Abhijit V; Prathep, Sumidtra; Souter, Michael J; Vavilala, Monica S; Qiu, Qian; Sharma, Deepak

    2017-07-01

    Secondary insults worsen outcomes after traumatic brain injury (TBI). However, data on intraoperative secondary insults are sparse. The primary aim of this study was to examine the prevalence of intraoperative secondary insults during orthopedic surgery after moderate-severe TBI. We also examined the impact of intraoperative secondary insults on postoperative head computed tomographic scan, intracranial pressure (ICP), and escalation of care within 24 hours of surgery. We reviewed medical records of TBI patients 18 years and above with Glasgow Coma Scale score Secondary insults examined were: systemic hypotension (systolic blood pressurehypertension (ICP>20 mm Hg), cerebral hypotension (cerebral perfusion pressure40 mm Hg), hypocarbia (end-tidal CO2hypertension), hyperglycemia (glucose>200 mg/dL), hypoglycemia (glucose38°C). A total of 78 patients (41 [18 to 81] y, 68% male) met the inclusion criteria. The most common intraoperative secondary insults were systemic hypotension (60%), intracranial hypertension and cerebral hypotension (50% and 45%, respectively, in patients with ICP monitoring), hypercarbia (32%), and hypocarbia (29%). Intraoperative secondary insults were associated with worsening of head computed tomography, postoperative decrease of Glasgow Coma Scale score by ≥2, and escalation of care. After Bonferroni correction, association between cerebral hypotension and postoperative escalation of care remained significant (Psecondary insults were common during orthopedic surgery in patients with TBI and were associated with postoperative escalation of care. Strategies to minimize intraoperative secondary insults are needed.

  4. Presurgical cleft lip and palate orthopedics: an overview

    Directory of Open Access Journals (Sweden)

    Alzain I

    2017-05-01

    Full Text Available Ibtesam Alzain,1 Waeil Batwa,2 Alex Cash,3 Zuhair A Murshid2 1Pediatric Dentistry, 2Orthodontic Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 3Cleft Lip and Palate Orthodontics, Queen Victoria NHS Foundation Trust, South Thames Cleft Service, London, UK Abstract: Patients with cleft lip and/or palate go through a lifelong journey of multidisciplinary care, starting from before birth and extending until adulthood. Presurgical orthopedic (PSO treatment is one of the earliest stages of this care plan. In this paper we provide a review of the PSO treatment. This review should help general and specialist dentists to better understand the cleft patient care path and to be able to answer patient queries more efficiently. The objectives of this paper were to review the basic principles of PSO treatment, the various types of techniques used in this therapy, and the protocol followed, and to critically evaluate the advantages and disadvantages of some of these techniques. In conclusion, we believe that PSO treatment, specifically nasoalveolar molding, does help to approximate the segments of the cleft maxilla and does reduce the intersegment space in readiness for the surgical closure of cleft sites. However, what we remain unable to prove equivocally at this point is whether the reduction in the dimensions of the cleft presurgically and the manipulation of the nasal complex benefit our patients in the long term. Keywords: presurgical orthopedic, nasoalveolar molding, cleft lip and palate

  5. [Orthopedic and trauma surgery in the German DRG system 2008].

    Science.gov (United States)

    Franz, D; Kaufmann, M; Siebert, C H; Windolf, J; Roeder, N

    2008-04-01

    The German DRG (diagnosis-related groups) system has been modified and updated into version 2008. For orthopedic and trauma surgery significant changes concerning coding of diagnoses, medical procedures and the DRG structure were made. The modified version has been analyzed in order to ascertain whether the DRG system is suitably qualified to fulfill the demands of the reimbursement system or whether further improvements are necessary. Analysis of the severity of relevant side-effect diagnoses, medical procedures and G-DRGs in the versions 2007 and 2008 was carried out based on the publications of the German DRG institute (InEK) and the German Institute of Medical Documentation and Information (DIMDI). Changes for 2008 focused on the development of DRG structure, DRG validation and codes for medical procedures. The outcome of these changes for German hospitals may vary depending on the range of activities. G-DRG system has become even more complex and the new regulations have also resulted in new problems associated with complications.. High demands are made on correct and complete coding of complex orthopedic and trauma surgery cases. Quality of case allocation within the G-DRG system has been improved. Nevertheless, further improvements of the G-DRG system are necessary, especially for cases with severe injuries.

  6. Effects of obesity on rehabilitation outcomes after orthopedic trauma.

    Science.gov (United States)

    Vincent, Heather K; Seay, Amanda N; Vincent, Kevin R; Atchison, James W; Sadasivan, Kalia

    2012-12-01

    This study examined whether differences existed in inpatient rehabilitation outcomes and therapy participation in nonobese and obese patients with orthopedic trauma. This was a retrospective study of 294 consecutive patients admitted to an inpatient rehabilitation hospital. Main outcomes included participation in therapy sessions, Functional Independence Measure (FIM) ratings, walking distance and stair climb, length of stay, FIM efficiency (FIM score gain/length of stay), and discharge to home. Data were stratified by patient body mass index values (nonobese, obese, ≥30 kg/m). There were no differences in therapy participation or length of stay between groups. Both total and motor FIM ratings at discharge were lower in obese patients compared with nonobese patients (P obese than in the nonobese group (2.6 ± 1.5 vs. 3.1 ± 1.5 points gained per day; P = 0.05). Walking distance and stair climb ability were similar between groups by discharge. Even morbidly obese patients attained some improvement with independence in walking. Obese patients make significant functional improvement during rehabilitation, but at a lesser magnitude and rate as their nonobese counterparts. Even with morbid obesity, small but important functional gains can occur during rehabilitation for orthopedic trauma.

  7. [Diagnostic control. Psychiatric comorbidity in patients of technical orthopedic units].

    Science.gov (United States)

    Lange, C; Heuft, G; Wetz, H H

    2001-04-01

    Because of the new hospital finance law a DRG (Diagnosis Related Groups) controlled discount liquidation under consideration of the medical impairment becomes necessary. In this paper the importance of a correct and complete description of the psychic comorbidity for the development of German-Refined-DRGs (GR-DRGs) in the orthopedic field is described. Therefore we analysed data of orthopedic in-patients, who are diagnosed by consultation of the clinic for psychosomatics and psychotherapy. A psychic comorbidity (ICD-10 Chapter F (V)) was diagnosed by 95% of the consulted patient. 30% of the patients showed difficulties in coping with their disease. 40% suffered from chronical psychoneurotic patterns and conflicts, which can be explained (a) as consequence of a difficult psychosocial adaptation by chronic disease or after an amputation (b) as basic mental disorders (c) as cause of the orthopaedic complications. Therefore the number of indications for a psychotherapeutic or psychiatric treatment is very high. The knowledge about a psychic comorbidity can--beside financial aspects--help the team on the orthopaedic station in the treatment of difficult patient.

  8. Prevalence of internet and social media usage in orthopedic surgery.

    Science.gov (United States)

    Curry, Emily; Li, Xinning; Nguyen, Joseph; Matzkin, Elizabeth

    2014-08-08

    Prior studies in other specialties have shown that social networking and Internet usage has become an increasingly important means of patient communication and referral. The purpose of this study is to evaluate the prevalence of Internet or social media usage in new patients referred to a major academic orthopedics center and to identify new avenues to optimize patient recruitment and communication. New patients were surveyed (n=752) between December 2012 to January 2013 in a major academic orthopaedic center to complete a 15-item questionnaire including social media and Internet usage information. Data was collected for all orthopaedic sub-specialties and statistical analysis was performed. Fifty percent of patients use social networking sites, such as Facebook. Sports medicine patients tend to be higher social networking users (35.9%) relative to other services (9.8-17.9%) and was statistically higher when compared to the joints/tumor service (Psocial media. Patients that travelled between 120 to 180 miles from the hospital for their visits were significantly more likely to be social media users, as were patients that did research on their condition prior to their new patient appointment. We conclude that orthopedic patients who use social media/Internet are more likely to be younger, researched their condition prior to their appointment and undergo a longer average day's travel (120-180 miles) to see a physician. In an increasingly competitive market, surgeons with younger patient populations will need to utilize social networking and the Internet to capture new patient referrals.

  9. Porous Structure Characterization in Titanium Coating for Surgical Implants

    Directory of Open Access Journals (Sweden)

    M.V. Oliveira

    2002-09-01

    Full Text Available Powder metallurgy techniques have been used to produce controlled porous structures, such as the porous coatings applied for dental and orthopedic surgical implants, which allow bony tissue ingrowth within the implant surface improving fixation. This work presents the processing and characterization of titanium porous coatings of different porosity levels, processed through powder metallurgy techniques. Pure titanium sponge powders were used for coating and Ti-6Al7Nb powder metallurgy rods were used as substrates. Characterization was made through quantitative metallographic image analysis using optical light microscope for coating porosity data and SEM analysis for evaluation of the coating/substrate interface integrity. The results allowed optimization of the processing parameters in order to obtain porous coatings that meet the requirements for use as implants.

  10. Short Implants: New Horizon in Implant Dentistry.

    Science.gov (United States)

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  11. The Orthopedically Disabled Child: Psychological Implications with an Individual Basis. July 1984 Revision.

    Science.gov (United States)

    Sigmon, Scott B.

    This study describes the implications of the Individual Psychology of Alfred Adler and field theory associated with Kurt Lewin in understanding orthopedically disabled children and points out that orthopedically disabled youngsters have a remarkable range of individual differences both in type of disability as well as level of adjustment.…

  12. Implantation, recoil implantation, and sputtering

    International Nuclear Information System (INIS)

    Kelly, R.

    1984-01-01

    Underlying ion-beam modification of surfaces is the more basic subject of particle-surface interaction. The ideas can be grouped into forward and backward features, i.e. those affecting the interior of the target and those leading to particle expulsion. Forward effects include the stopping of the incident particles and the deposition of energy, both governed by integral equations which are easily set up but difficult to solve. Closely related is recoil implantation where emphasis is placed not on the stopping of the incident particles but on their interaction with target atoms with resulting implantation of these atoms. Backward effects, all of which are denoted as sputtering, are in general either of collisional, thermal, electronic, or exfoliational origin. (Auth.)

  13. An Overview of Internal Fixation Implant Metallurgy and Galvanic Corrosion Effects.

    Science.gov (United States)

    Koh, Justin; Berger, Aaron; Benhaim, Prosper

    2015-08-01

    Orthopedic and hand surgery implants for internal fixation of fractures have evolved substantially over the past 50 years. Newer metal compositions have been used, and new standards have been applied to older alloys, resulting in modern implants with unique physical properties and better clinical performances. Conventional wisdom has long dictated that implanting different metals should be avoided, but few guidelines exist regarding the safety of using in proximity implant systems of dissimilar metals. To better characterize the landscape of internal fixation implant metallurgy, we have compiled the recommendations and conclusions of the currently available and pertinent literature. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  14. Clinical evaluation of a commercial orthopedic metal artifact reduction tool for CT simulations in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Li Hua; Noel, Camille; Chen, Haijian; Harold Li, H.; Low, Daniel; Moore, Kevin; Klahr, Paul; Michalski, Jeff; Gay, Hiram A.; Thorstad, Wade; Mutic, Sasa [Department of Radiation Oncology, Washington University, St. Louis, Missouri 63110 (United States); Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California 90095 (United States); Department of Radiation Oncology, University of California San Diego, San Diego, California 92093 (United States); Philips Healthcare System, Cleveland, Ohio 44143 (United States); Department of Radiation Oncology, Washington University, St. Louis, Missouri 63110 (United States)

    2012-12-15

    Purpose: Severe artifacts in kilovoltage-CT simulation images caused by large metallic implants can significantly degrade the conspicuity and apparent CT Hounsfield number of targets and anatomic structures, jeopardize the confidence of anatomical segmentation, and introduce inaccuracies into the radiation therapy treatment planning process. This study evaluated the performance of the first commercial orthopedic metal artifact reduction function (O-MAR) for radiation therapy, and investigated its clinical applications in treatment planning. Methods: Both phantom and clinical data were used for the evaluation. The CIRS electron density phantom with known physical (and electron) density plugs and removable titanium implants was scanned on a Philips Brilliance Big Bore 16-slice CT simulator. The CT Hounsfield numbers of density plugs on both uncorrected and O-MAR corrected images were compared. Treatment planning accuracy was evaluated by comparing simulated dose distributions computed using the true density images, uncorrected images, and O-MAR corrected images. Ten CT image sets of patients with large hip implants were processed with the O-MAR function and evaluated by two radiation oncologists using a five-point score for overall image quality, anatomical conspicuity, and CT Hounsfield number accuracy. By utilizing the same structure contours delineated from the O-MAR corrected images, clinical IMRT treatment plans for five patients were computed on the uncorrected and O-MAR corrected images, respectively, and compared. Results: Results of the phantom study indicated that CT Hounsfield number accuracy and noise were improved on the O-MAR corrected images, especially for images with bilateral metal implants. The {gamma} pass rates of the simulated dose distributions computed on the uncorrected and O-MAR corrected images referenced to those of the true densities were higher than 99.9% (even when using 1% and 3 mm distance-to-agreement criterion), suggesting that dose

  15. Electrochemical properties of ion implanted silicon

    International Nuclear Information System (INIS)

    Pham minh Tan.

    1979-11-01

    The electrochemical behaviour of ion implanted silicon in contact with hydrofluoric acid solution was investigated. It was shown that the implanted layer on silicon changes profoundly its electrochemical properties (photopotential, interface impedance, rest potential, corrosion, current-potential behaviour, anodic dissolution of silicon, redox reaction). These changes depend strongly on the implantation parameters such as ion dose, ion energy, thermal treatment and ion mass and are weakly dependent on the chemical nature of the implantation ion. The experimental results were evaluated and interpreted in terms of the semiconductor electrochemical concepts taking into account the interaction of energetic ions with the solid surface. The observed effects are thus attributed to the implantation induced damage of silicon lattice and can be used for profiling of the implanted layer and the electrochemical treatment of the silicon surface. (author)

  16. The effect of load on heat production, thermal effects and expenditure of time during implant site preparation - an experimental ex vivo comparison between piezosurgery and conventional drilling.

    Science.gov (United States)

    Stelzle, Florian; Frenkel, Carsten; Riemann, Max; Knipfer, Christian; Stockmann, Philipp; Nkenke, Emeka

    2014-02-01

    Piezoelectric surgery (PS) is meant to be a gentle osteotomy method. The aim of this study was to compare piezosurgical vs. conventional drilling methods for implant site preparation (ISP) - focusing on load-dependent thermal effect on hard tissue and the expenditure of ISP time. Three hundred and sixty ISP were performed on ex vivo pig heads using piezosurgery, spiral burs (SB) and trephine burs (TB). The load applied was increased from 0 to 1000 g in 100-g intervals. Temperature within the bone was measured with a thermocouple, and duration was recorded with a stop watch. Thermal effects were histomorphometrically analysed. Twelve ISPs per technique were performed at the lateral wall of the maxillary sinus. PS yields the highest mean temperatures (48.6 ± 3.4°C) and thermal effects (200.7 ± 44.4 μm), both at 900-1000 g. Duration is reduced with a plus of load and significantly longer in either case for PS (P < 0.05). There is a correlation of the applied load with all other examined factors for PS and TB. Temperature and histological effects decrease for SB beyond 500 g. PS yields significantly higher temperatures and thermal tissue alterations on load levels higher than 500 g and is significantly slower for ISP compared to SB and TB. For ISP with PS, a maximum load of 400 g should be maintained. © 2012 John Wiley & Sons A/S.

  17. Significant Artifact Reduction at 1.5T and 3T MRI by the Use of a Cochlear Implant with Removable Magnet: An Experimental Human Cadaver Study.

    Science.gov (United States)

    Wagner, Franca; Wimmer, Wilhelm; Leidolt, Lars; Vischer, Mattheus; Weder, Stefan; Wiest, Roland; Mantokoudis, Georgios; Caversaccio, Marco D

    2015-01-01

    Cochlear implants (CIs) are standard treatment for postlingually deafened individuals and prelingually deafened children. This human cadaver study evaluated diagnostic usefulness, image quality and artifacts in 1.5T and 3T magnetic resonance (MR) brain scans after CI with a removable magnet. Three criteria (diagnostic usefulness, image quality, artifacts) were assessed at 1.5T and 3T in five cadaver heads with CI. The brain magnetic resonance scans were performed with and without the magnet in situ. The criteria were analyzed by two blinded neuroradiologists, with focus on image distortion and limitation of the diagnostic value of the acquired MR images. MR images with the magnet in situ were all compromised by artifacts caused by the CI. After removal of the magnet, MR scans showed an unequivocal artifact reduction with significant improvement of the image quality and diagnostic usefulness, both at 1.5T and 3T. Visibility of the brain stem, cerebellopontine angle, and parieto-occipital lobe ipsilateral to the CI increased significantly after magnet removal. The results indicate the possible advantages for 1.5T and 3T MR scanning of the brain in CI carriers with removable magnets. Our findings support use of CIs with removable magnets, especially in patients with chronic intracranial pathologies.

  18. Biodegradable magnesium-based implants in bone studied by synchrotron radiation microtomography

    Science.gov (United States)

    Moosmann, Julian; Zeller-Plumhoff, Berit; Wieland, D. C. Florian; Galli, Silvia; Krüger, Diana; Dose, Thomas; Burmester, Hilmar; Wilde, Fabian; Bech, Martin; Peruzzi, Niccolò; Wiese, Björn; Hipp, Alexander; Beckmann, Felix; Hammel, Jörg; Willumeit-Römer, Regine

    2017-09-01

    Permanent implants made of titanium or its alloys are the gold standard in many orthopedic and traumatological applications due to their good biocompatibility and mechanical properties. However, a second surgical intervention is required for this kind of implants as they have to be removed in the case of children that are still growing or on patient's demand. Therefore, magnesium-based implants are considered for medical applications as they are degraded under physiological conditions. The major challenge is tailoring the degradation in a manner that is suitable for a biological environment and such that stabilization of the bone is provided for a controlled period. In order to understand failure mechanisms of magnesium-based implants in orthopedic applications and, further, to better understand the osseointegration, screw implants in bone are studied under mechanical load by means of a push-out device installed at the imaging beamline P05 of PETRA III at DESY. Conventional absorption contrast microtomography and phasecontrast techniques are applied in order to monitor the bone-to-implant interface under increasing load conditions. In this proof-of-concept study, first results from an in situ push-out experiment are presented.

  19. Dental Implant Surgery

    Science.gov (United States)

    ... here to find out more. Dental Implant Surgery Dental Implant Surgery Dental implant surgery is, of course, ... to find out more. Wisdom Teeth Management Wisdom Teeth Management An impacted wisdom tooth can damage neighboring ...

  20. Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Mehrnaz Karimi

    1992-04-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss . In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  1. Strain driven fast osseointegration of implants

    Directory of Open Access Journals (Sweden)

    Wiesmann Hans-Peter

    2005-09-01

    Full Text Available Abstract Background Although the bone's capability of dental implant osseointegration has clinically been utilised as early as in the Gallo-Roman population, the specific mechanisms for the emergence and maintenance of peri-implant bone under functional load have not been identified. Here we show that under immediate loading of specially designed dental implants with masticatory loads, osseointegration is rapidly achieved. Methods We examined the bone reaction around non- and immediately loaded dental implants inserted in the mandible of mature minipigs during the presently assumed time for osseointegration. We used threaded conical titanium implants containing a titanium2+ oxide surface, allowing direct bone contact after insertion. The external geometry was designed according to finite element analysis: the calculation showed that physiological amplitudes of strain (500–3,000 ustrain generated through mastication were homogenously distributed in peri-implant bone. The strain-energy density (SED rate under assessment of a 1 Hz loading cycle was 150 Jm-3 s-1, peak dislocations were lower then nm. Results Bone was in direct contact to the implant surface (bone/implant contact rate 90% from day one of implant insertion, as quantified by undecalcified histological sections. This effect was substantiated by ultrastructural analysis of intimate osteoblast attachment and mature collagen mineralisation at the titanium surface. We detected no loss in the intimate bone/implant bond during the experimental period of either control or experimental animals, indicating that immediate load had no adverse effect on bone structure in peri-implant bone. Conclusion In terms of clinical relevance, the load related bone reaction at the implant interface may in combination with substrate effects be responsible for an immediate osseointegration state.

  2. Effects of external stress on biodegradable orthopedic materials: A review

    Directory of Open Access Journals (Sweden)

    Xuan Li

    2016-09-01

    Full Text Available Biodegradable orthopedic materials (BOMs are used in rehabilitation and reconstruction of fractured tissues. The response of BOMs to the combined action of physiological stress and corrosion is an important issue in vivo since stress-assisted degradation and cracking are common. Although the degradation behavior and kinetics of BOMs have been investigated under static conditions, stress effects can be very serious and even fatal in the dynamic physiological environment. Since stress is unavoidable in biomedical applications of BOMs, recent work has focused on the evaluation and prediction of the properties of BOMs under stress in corrosive media. This article reviews recent progress in this important area focusing on biodegradable metals, polymers, and ceramics.

  3. Barriers to the clinical translation of orthopedic tissue engineering.

    Science.gov (United States)

    Evans, Christopher H

    2011-12-01

    Tissue engineering and regenerative medicine have been the subject of increasingly intensive research for over 20 years, and there is concern in some quarters over the lack of clinically useful products despite the large sums of money invested. This review provides one perspective on orthopedic applications from a biologist working in academia. It is suggested that the delay in clinical application is not atypical of new, biologically based technologies. Some barriers to progress are acknowledged and discussed, but it is also noted that preclinical studies have identified several promising types of cells, scaffolds, and morphogenetic signals, which, although not optimal, are worth advancing toward human trials to establish a bridgehead in the clinic. Although this transitional technology will be replaced by more sophisticated, subsequent systems, it will perform valuable pioneering functions and facilitate the clinical development of the field. Some strategies for achieving this are suggested. © Mary Ann Liebert, Inc.

  4. Evaluation of occupational and patient radiation doses in orthopedic surgery

    International Nuclear Information System (INIS)

    Sulieman, A.; Alzimami, K.; Habeeballa, B.; Osman, H.; Abdelaziz, I.; Sassi, S.A.; Sam, A.K.

    2015-01-01

    This study intends to measure the radiation dose to patients and staff during (i) Dynamic Hip Screw (DHS) and (ii) Dynamic Cannula Screw (DCS) and to evaluate entrance surface Air kerma (ESAK) dose and organ doses and effective doses. Calibrated Thermoluminescence dosimeters (TLD-GR200A) were used. The mean patients’ doses were 0.46 mGy and 0.07 mGy for DHS and DCS procedures, respectively. The mean staff doses at the thyroid and chest were 4.69 mGy and 1.21 mGy per procedure. The mean organ and effective dose for patients and staff were higher in DHS compared to DCS. Orthopedic surgeons were exposed to unnecessary radiation doses due to the lack of protection measures. The radiation dose per hip procedure is within the safety limit and less than the previous studies

  5. Operation of low-energy ion implanters for Si, N, C ion implantation into silicon and glassy carbon

    International Nuclear Information System (INIS)

    Carder, D.A.; Markwitz, A.

    2009-01-01

    This report details the operation of the low-energy ion implanters at GNS Science for C, N and Si implantations. Two implanters are presented, from a description of the components through to instructions for operation. Historically the implanters have been identified with the labels 'industrial' and 'experimental'. However, the machines only differ significantly in the species of ions available for implantation and sample temperature during implantation. Both machines have been custom designed for research purposes, with a wide range of ion species available for ion implantation and the ability to implant two ions into the same sample at the same time from two different ion sources. A fast sample transfer capability and homogenous scanning profiles are featured in both cases. Samples up to 13 mm 2 can be implanted, with the ability to implant at temperatures down to liquid nitrogen temperatures. The implanters have been used to implant 28 Si + , 14 N + and 12 C + into silicon and glassy carbon substrates. Rutherford backscattering spectroscopy has been used to analyse the implanted material. From the data a Si 30 C 61 N 9 layer was measured extending from the surface to a depth of about 77 ± 2 nm for (100) silicon implanted with 12 C + and 14 N + at multiple energies. Silicon and nitrogen ion implantation into glassy carbon produced a Si (40.5 %), C (38 %), N (19.5 %) and O (2%) layer centred around a depth of 50 ± 2 nm from the surface. (author). 8 refs., 20 figs

  6. Simulations of Proton Implantation in Silicon Carbide (SiC)

    Science.gov (United States)

    2016-03-31

    Simulations of Proton Implantation in Silicon Carbide (SiC) Jonathan P. McCandless, Hailong Chen, Philip X.-L. Feng Electrical Engineering, Case...of implanting protons (hydrogen ions, H+) into SiC thin layers on silicon (Si) substrate, and explore the ion implantation conditions that are...relevant to experimental radiation of SiC layers. Keywords: silicon carbide (SiC); radiation effects; ion implantation ; proton; stopping and range of

  7. Amorphization of tantalum by boron and phosphorus ion implantation

    International Nuclear Information System (INIS)

    Thome, L.; Benyagoub, A.; Bernas, H.; Pivin, J.C.; Cahn, R.W.

    1984-01-01

    The nature and depth dependence of the disorder produced by B and P implantation in Ta single crystals were studied in situ via channeling experiments and after implantation via grazing incidence electron diffraction experiments. The correlation of experimental results with implanted impurity profiles determined by SIMS shows that amorphous Ta-B and Ta-P alloys are produced for, respectively, 19% and 8% B and P concentrations in the implanted layer [fr

  8. Orthopedic specialty hospitals: centers of excellence or greed machines?

    Science.gov (United States)

    Badlani, Neil; Boden, Scott; Phillips, Frank

    2012-03-07

    Orthopedic specialty hospitals have recently been the subject of debate. They are patient-centered, physician-friendly health care alternatives that take advantage of the economic efficiencies of specialization. Medically, they provide a higher quality of care and increase patient and physician satisfaction. Economically, they are more efficient and profitable than general hospitals. They also positively affect society through the taxes they pay and the beneficial aspects of the competition they provide to general hospitals. Their ability to provide a disruptive innovation to the existing hospital industry will lead to lower costs and greater access to health care. However, critics say that physician ownership presents potential conflicts of interest and leads to overuse of medical care. Some general hospitals are suffering as a result of unfair specialty hospital practices, and a few drastic medical complications have occurred at specialty hospitals. Specialty hospitals have been scrutinized for increasing the inequality of health care and continue to be a target of government regulations. In this article, the pros and cons are examined, and the Emory Orthopaedics and Spine Hospital is analyzed as an example. Orthopedic specialty hospitals provide excellent care and are great assets to society. Competition between specialty and general hospitals has provided added value to patients and taxpayers. However, physicians must take more responsibility in their appropriate and ethical leadership. It is critical to recognize financial conflicts of interest, disclose ownership, and act ethically. Patient care cannot be compromised. With thoughtful and efficient leadership, specialty hospitals can be an integral part of improving health care in the long term. Copyright 2012, SLACK Incorporated.

  9. Marijuana use and mortality following orthopedic surgical procedures.

    Science.gov (United States)

    Moon, Andrew S; Smith, Walter; Mullen, Sawyer; Ponce, Brent A; McGwin, Gerald; Shah, Ashish; Naranje, Sameer M

    2018-03-20

    The association between marijuana use and surgical procedures is a matter of increasing societal relevance that has not been well studied in the literature. The primary aim of this study is to evaluate the relationship between marijuana use and in-hospital mortality, as well as to assess associated comorbidities in patients undergoing commonly billed orthopedic surgeries. The National Inpatient Sample (NIS) database from 2010 to 2014 was used to determine the odds ratios for the associations between marijuana use and in-hospital mortality, heart failure (HF), stroke, and cardiac disease (CD) in patients undergoing five common orthopedic procedures: hip (THA), knee (TKA), and shoulder arthroplasty (TSA), spinal fusion, and traumatic femur fracture fixation. Of 9,561,963 patients who underwent one of the five selected procedures in the four-year period, 26,416 (0.28%) were identified with a diagnosis of marijuana use disorder. In hip and knee arthroplasty patients, marijuana use was associated with decreased odds of mortality compared to no marijuana use (pmarijuana use (0.70%), which was associated with decreased odds of mortality (p = 0.0483), HF (p = 0.0076), and CD (p = 0.0003). For spinal fusions, marijuana use was associated with increased odds of stroke (pMarijuana use in patients undergoing shoulder arthroplasty was associated with decreased odds of mortality (pmarijuana use was associated with decreased mortality in patients undergoing THA, TKA, TSA and traumatic femur fixation, although the significance of these findings remains unclear. More research is needed to provide insight into these associations in a growing surgical population.

  10. Evaluation of occupational and patient radiation doses in orthopedic surgery

    International Nuclear Information System (INIS)

    Sulieman, A.; Habiballah, B.; Abdelaziz, I.; Alzimami, K.; Osman, H.; Omer, H.; Sassi, S. A.

    2014-08-01

    Orthopedists are exposed to considerable radiation dose during orthopedic surgeries procedures. The staff is not well trained in radiation protection aspects and its related risks. In Sudan, regular monitoring services are not provided for all staff in radiology or interventional personnel. It is mandatory to measure staff and patient exposure in order to radiology departments. The main objectives of this study are: to measure the radiation dose to patients and staff during (i) Dynamic Hip Screw (Dhs) and (i i) Dynamic Cannula Screw (Dcs); to estimate the risk of the aforementioned procedures and to evaluate entrance surface dose (ESD) and organ dose to specific radiosensitive patients organs. The measurements were performed in Medical Corps Hospital, Sudan. The dose was measured for unprotected organs of staff and patient as well as scattering radiation. Calibrated Thermoluminescence dosimeters (TLD-Gr-200) of lithium fluoride (LiF:Mg, Cu,P) were used for ESD measurements. TLD signal are obtained using automatic TLD Reader model (Plc-3). The mean patients doses were 0.46 mGy and 0.07 for Dhs and Dcs procedures, respectively. The mean staff doses at the thyroid and chest were 4.69 mGy and 1.21 mGy per procedure. The mean radiation dose for staff was higher in Dhs compared to Dcs. This can be attributed to the long fluoroscopic exposures due to the complication of the procedures. Efforts should be made to reduce radiation exposure to orthopedic patients, and operating surgeons especially those with high work load. Staff training and regular monitoring will reduce the radiation dose for both patients and staff. (Author)

  11. Orthopedic surgery in cerebral palsy: Instructional course lecture

    Directory of Open Access Journals (Sweden)

    Deepak Sharan

    2017-01-01

    Full Text Available Orthopedic surgery (OS plays an important role in the management of cerebral palsy (CP. The objectives of OS are to optimize functions and prevent deformity. Newer developments in OS for CP include emphasis on hip surveillance, minimally invasive procedures, use of external fixators instead of plates and screws, better understanding of lever arm dysfunctions (that can only be corrected by bony OS, orthopedic selective spasticity-control surgery, and single-event multilevel lever arm restoration and anti spasticity surgery, which have led to significant improvements in gross motor function and ambulation, especially in spastic quadriplegia, athetosis, and dystonia. The results of OS can be dramatic and life altering for the person with CP and their caregivers if it is performed meticulously by a specialized surgical team, at the appropriate age, for the correct indications, employing sound biomechanical principles and is followed by physician-led, protocol based, intensive, multidisciplinary, institutional rehabilitation, and long term followup. However, OS can be a double-edged sword, and if performed less than optimally, and without the supporting multidisciplinary medical and rehabilitation team, expertise and infrastructure, it often leads to significant functional worsening of the person with CP, including irretrievable loss of previous ambulatory capacity. OS must be integrated into the long term management of the person with CP and should be anticipated and planned at the optimal time and not viewed as a “last resort” intervention or failure of rehabilitation. This instructional course lecture reviews the relevant contemporary principles and techniques of OS in CP.

  12. Evaluation of occupational and patient radiation doses in orthopedic surgery

    Energy Technology Data Exchange (ETDEWEB)

    Sulieman, A. [Salman bin Abdulaziz University, College of Applied Medical Sciences, Radiology and Medical Imaging Department, P.O. Box 422, Alkharj (Saudi Arabia); Habiballah, B.; Abdelaziz, I. [Sudan Univesity of Science and Technology, College of Medical Radiologic Sciences, P.O. Box 1908, Khartoum (Sudan); Alzimami, K. [King Saud University, College of Applied Medical Sciences, Radiological Sciences Department, P.O. Box 10219, 11433 Riyadh (Saudi Arabia); Osman, H. [Taif University, College of Applied Medical Science, Radiology Department, Taif (Saudi Arabia); Omer, H. [University of Dammam, Faculty of Medicine, Dammam (Saudi Arabia); Sassi, S. A., E-mail: Abdelmoneim_a@yahoo.com [Prince Sultan Medical City, Department of Medical Physics, Riyadh (Saudi Arabia)

    2014-08-15

    Orthopedists are exposed to considerable radiation dose during orthopedic surgeries procedures. The staff is not well trained in radiation protection aspects and its related risks. In Sudan, regular monitoring services are not provided for all staff in radiology or interventional personnel. It is mandatory to measure staff and patient exposure in order to radiology departments. The main objectives of this study are: to measure the radiation dose to patients and staff during (i) Dynamic Hip Screw (Dhs) and (i i) Dynamic Cannula Screw (Dcs); to estimate the risk of the aforementioned procedures and to evaluate entrance surface dose (ESD) and organ dose to specific radiosensitive patients organs. The measurements were performed in Medical Corps Hospital, Sudan. The dose was measured for unprotected organs of staff and patient as well as scattering radiation. Calibrated Thermoluminescence dosimeters (TLD-Gr-200) of lithium fluoride (LiF:Mg, Cu,P) were used for ESD measurements. TLD signal are obtained using automatic TLD Reader model (Plc-3). The mean patients doses were 0.46 mGy and 0.07 for Dhs and Dcs procedures, respectively. The mean staff doses at the thyroid and chest were 4.69 mGy and 1.21 mGy per procedure. The mean radiation dose for staff was higher in Dhs compared to Dcs. This can be attributed to the long fluoroscopic exposures due to the complication of the procedures. Efforts should be made to reduce radiation exposure to orthopedic patients, and operating surgeons especially those with high work load. Staff training and regular monitoring will reduce the radiation dose for both patients and staff. (Author)

  13. SPECT/CT imaging in general orthopedic practice.

    Science.gov (United States)

    Scharf, Stephen

    2009-09-01

    The availability of hybrid devices that combine the latest single-photon emission computed tomography (SPECT) imaging technology with multislice computed tomography (CT) scanning has allowed us to detect subtle, nonspecific abnormalities on bone scans and interpret them as specific focal areas of pathology. Abnormalities in the spine can be separated into those caused by pars fractures, facet joint arthritis, or osteophyte formation on vertebral bodies. Compression fractures can be distinguished from severe degenerative disease, both of which can cause intense activity across the spine on either planar or SPECT imaging. Localizing activity in patients who have had spinal fusion can provide tremendous insight into the causes of therapeutic failures. Infections of the spine now can be diagnosed with gallium SPECT/CT, despite the fact that gallium has long been abandoned because of its failure to detect spine infection on either planar or SPECT imaging. Small focal abnormalities in the feet and ankles can be localized well enough to make specific orthopedic diagnoses on the basis of their location. Moreover, when radiographic imaging provides equivocal or inadequate information, SPECT/CT can provide a road map for further diagnostic studies and has been invaluable in planning surgery. Our ability to localize activity within a bone or at an articular surface has allowed us to distinguish between fractures and joint disease. Increased activity associated with congenital anomalies, such as tarsal coalition and Bertolotti's syndrome have allowed us to understand the pathophysiology of these conditions, to confirm them as the cause of the patient's symptoms, and to provide information that is useful in determining appropriate clinical management. As our experience broadens, SPECT/CT will undoubtedly become an important tool in the evaluation and management of a wider variety of orthopedic patients.

  14. Effects of ion-implanted C on the microstructure and surface mechanical properties of Fe alloys implanted with Ti

    International Nuclear Information System (INIS)

    Follstaedt, D.M.; Knapp, J.A.; Pope, L.E.; Yost, F.G.; Picraux, S.T.

    1984-01-01

    The microstructural and tribological effects of ion implanting C into Ti-implanted, Fe-based alloys are examined and compared to the influence of C introduced by vacuum carburization during Ti implantation alone. The amorphous surface alloy formed by Ti implantation of pure Fe increases in thickness when additional C is implanted at depths containing Ti but beyond the range of carburization. Pin-on-disc tests of 15-5 PH stainless steel show that implantation of both Ti and C reduces friction significantly under conditions where no reduction is obtained by Ti implantation alone; wear depths are also less when C is implanted. All available experimental results can be accounted for by consideration of the thickness and Ti concentration of the amorphous Fe-Ti-C alloy. The thicker amorphous layer on samples implanted with additional C extends tribological benefits to more severe wear regimes

  15. Electromechanical impedance method to assess dental implant stability

    International Nuclear Information System (INIS)

    Tabrizi, Aydin; Rizzo, Piervincenzo; Ochs, Mark W

    2012-01-01

    The stability of a dental implant is a prerequisite for supporting a load-bearing prosthesis and establishment of a functional bone–implant system. Reliable and noninvasive methods able to assess the bone interface of dental and orthopedic implants (osseointegration) are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, we propose the electromechanical impedance method as a novel approach for the assessment of dental implant stability. Nobel Biocare ® implants with a size of 4.3 mm diameter ×13 mm length were placed inside bovine bones that were then immersed in a solution of nitric acid to allow material degradation. The degradation simulated the inverse process of bone healing. The implant–bone systems were monitored by bonding a piezoceramic transducer (PZT) to the implants’ abutment and measuring the admittance of the PZT over time. It was found that the PZT’s admittance and the statistical features associated with its analysis are sensitive to the degradation of the bones and can be correlated to the loss of calcium measured by means of the atomic absorption spectroscopy method. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of dental implant stability and integrity. (paper)

  16. Optimization of cell adhesion on mg based implant materials by pre-incubation under cell culture conditions.

    Science.gov (United States)

    Willumeit, Regine; Möhring, Anneke; Feyerabend, Frank

    2014-05-05

    Magnesium based implants could revolutionize applications where orthopedic implants such as nails, screws or bone plates are used because they are load bearing and degrade over time. This prevents a second surgery to remove conventional implants. To improve the biocompatibility we studied here if and for how long a pre-incubation of the material under cell culture conditions is favorable for cell attachment and proliferation. For two materials, Mg and Mg10Gd1Nd, we could show that 6 h pre-incubation are already enough to form a natural protective layer suitable for cell culture.

  17. Optimization of Cell Adhesion on Mg Based Implant Materials by Pre-Incubation under Cell Culture Conditions

    Directory of Open Access Journals (Sweden)

    Regine Willumeit

    2014-05-01

    Full Text Available Magnesium based implants could revolutionize applications where orthopedic implants such as nails, screws or bone plates are used because they are load bearing and degrade over time. This prevents a second surgery to remove conventional implants. To improve the biocompatibility we studied here if and for how long a pre-incubation of the material under cell culture conditions is favorable for cell attachment and proliferation. For two materials, Mg and Mg10Gd1Nd, we could show that 6 h pre-incubation are already enough to form a natural protective layer suitable for cell culture.

  18. Artifacts Quantification of Metal Implants in MRI

    Science.gov (United States)

    Vrachnis, I. N.; Vlachopoulos, G. F.; Maris, T. G.; Costaridou, L. I.

    2017-11-01

    The presence of materials with different magnetic properties, such as metal implants, causes distortion of the magnetic field locally, resulting in signal voids and pile ups, i.e. susceptibility artifacts in MRI. Quantitative and unbiased measurement of the artifact is prerequisite for optimization of acquisition parameters. In this study an image gradient based segmentation method is proposed for susceptibility artifact quantification. The method captures abrupt signal alterations by calculation of the image gradient. Then the artifact is quantified in terms of its extent by an automated cross entropy thresholding method as image area percentage. The proposed method for artifact quantification was tested in phantoms containing two orthopedic implants with significantly different magnetic permeabilities. The method was compared against a method proposed in the literature, considered as a reference, demonstrating moderate to good correlation (Spearman’s rho = 0.62 and 0.802 in case of titanium and stainless steel implants). The automated character of the proposed quantification method seems promising towards MRI acquisition parameter optimization.

  19. Sacroiliac joint stability: Finite element analysis of implant number, orientation, and superior implant length.

    Science.gov (United States)

    Lindsey, Derek P; Kiapour, Ali; Yerby, Scott A; Goel, Vijay K

    2018-03-18

    To analyze how various implants placement variables affect sacroiliac (SI) joint range of motion. An experimentally validated finite element model of the lumbar spine and pelvis was used to simulate a fusion of the SI joint using various placement configurations of triangular implants (iFuse Implant System ® ). Placement configurations were varied by changing implant orientation, superior implant length, and number of implants. The range of motion of the SI joint was calculated using a constant moment of 10 N-m with a follower load of 400 N. The changes in motion were compared between the treatment groups to assess how the different variables affected the overall motion of the SI joint. Transarticular placement of 3 implants with superior implants that end in the middle of the sacrum resulted in the greatest reduction in range of motion (flexion/extension = 73%, lateral bending = 42%, axial rotation = 72%). The range of motions of the SI joints were reduced with use of transarticular orientation (9%-18%) when compared with an inline orientation. The use of a superior implant that ended mid-sacrum resulted in median reductions of (8%-14%) when compared with a superior implant that ended in the middle of the ala. Reducing the number of implants, resulted in increased SI joint range of motions for the 1 and 2 implant models of 29%-133% and 2%-39%, respectively, when compared with the 3 implant model. Using a validated finite element model we demonstrated that placement of 3 implants across the SI joint using a transarticular orientation with superior implant reaching the sacral midline resulted in the most stable construct. Additional clinical studies may be required to confirm these results.

  20. Complications after cardiac implantable electronic device implantations

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  1. Cutaneous and systemic hypersensitivity reactions to metallic implants

    DEFF Research Database (Denmark)

    Basko-Plluska, Juliana L; Thyssen, Jacob P; Schalock, Peter C

    2011-01-01

    Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous....... However, other metal ions as well as bone cement components can cause such hypersensitivity reactions. To complicate things, patients may also develop delayed-type hypersensitivity reactions to metals (ie, in-stent restenosis, prosthesis loosening, inflammation, pain, or allergic contact dermatitis...

  2. Influence of podiatry on orthopedic surgery at a level I trauma center.

    Science.gov (United States)

    Jakoi, Andre M; Old, Andrew B; O'Neill, Craig A; Stein, Benjamin E; Stander, Eric P; Rosenblatt, Joseph; Herman, Martin J

    2014-06-01

    Level I trauma centers frequently see trauma at or below the ankle, which requires consultation with the orthopedic surgery department. However, as podiatry programs begin to firmly establish themselves in more Level I trauma centers, their consultations increase, ultimately taking those once seen by orthopedic surgery. A review of the literature demonstrates that this paradigm shift has yet to be discussed. The purpose of this study was to determine how many, if any, lower extremity fracture consultations a newly developed podiatry program would take from the orthopedic surgery department. A retrospective review was performed of emergency department records from January 2007 to December 2011. Seventeen different emergency department diagnoses were used to search the database. Ultimately, each patient's emergency department course was researched. Several trends were noted. First, if trauma surgery was involved, only the orthopedic surgery department was consulted for any injuries at or below the ankle. Second, the emergency department tended to consult the podiatry program only between the hours of 8 am and 6 pm. Third, as the podiatry program became more established, their number of consultations increased yearly, and, coincidentally, the orthopedic surgery department's consultations decreased. Finally, high-energy traumas involved only the orthopedic surgery department. Whether the orthopedic surgery department or podiatry program is consulted regarding trauma surgery is likely hospital dependent. Copyright 2014, SLACK Incorporated.

  3. [Use of diagnostic templates at stages of prosthetics treatment with implant-retained restorations].

    Science.gov (United States)

    Gvetadze, R Sh; Abramyan, S V; Ivanov, A A; Nubaryan, A P

    The comparative analysis of efficiency of various types of diagnostic templates for planning orthopedic treatment of 50 patients with partial or complete absence of teeth was performed. The patients were divided in 3 groups according to template manufacturing technique. All diagnostic templates made in accordance with clinical conditions allowed transfering digital data of the scheduled prosthetic construction for virtual implantation planning. Advantages and pitfalls of each template type are discussed.

  4. MRI of hip prostheses using single-point methods : in vitro studies towards the artifact-free imaging of individuals with metal implants

    NARCIS (Netherlands)

    Ramos Cabrer, P.; Duynhoven, van J.P.M.; Toorn, van der A.; Nicolaij, K.

    2004-01-01

    Use of magnetic resonance imaging (MRI) in individuals with orthopedic implants is limited because of the large distortions caused by metallic components. As a possible solution for this problem, we suggest the use of single-point imaging (SPI) methods, which are immune to the susceptibility

  5. Effect of pore size on bone ingrowth into porous titanium implants fabricated by additive manufacturing: An in vivo experiment

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Naoya, E-mail: tani110@kuhp.kyoto-u.ac.jp [Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 (Japan); Fujibayashi, Shunsuke, E-mail: shfuji@kuhp.kyoto-u.ac.jp [Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 (Japan); Takemoto, Mitsuru, E-mail: m.take@kuhp.kyoto-u.ac.jp [Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 (Japan); Sasaki, Kiyoyuki, E-mail: kiy-sasaki@spcom.co.jp [Sagawa Printing Co., Ltd., 5-3, Inui, Morimoto-Cho, Mukou-Shi, Kyoto 617-8588 (Japan); Otsuki, Bungo, E-mail: bungo@kuhp.kyoto-u.ac.jp [Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 (Japan); Nakamura, Takashi, E-mail: ntaka@kuhp.kyoto-u.ac.jp [National Hospital Organization Kyoto Medical Center, 1-1, Mukaihatacho, Hukakusa, Hushimi, Kyoto 612-8555 (Japan); Matsushita, Tomiharu, E-mail: matsushi@isc.chubu.ac.jp [Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan); Kokubo, Tadashi, E-mail: kokubo@isc.chubu.ac.jp [Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan); Matsuda, Shuichi, E-mail: smat522@kuhp.kyoto-u.ac.jp [Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 (Japan)

    2016-02-01

    Selective laser melting (SLM) is an additive manufacturing technique with the ability to produce metallic scaffolds with accurately controlled pore size, porosity, and interconnectivity for orthopedic applications. However, the optimal pore structure of porous titanium manufactured by SLM remains unclear. In this study, we evaluated the effect of pore size with constant porosity on in vivo bone ingrowth in rabbits into porous titanium implants manufactured by SLM. Three porous titanium implants (with an intended porosity of 65% and pore sizes of 300, 600, and 900 μm, designated the P300, P600, and P900 implants, respectively) were manufactured by SLM. A diamond lattice was adapted as the basic structure. Their porous structures were evaluated and verified using microfocus X-ray computed tomography. Their bone–implant fixation ability was evaluated by their implantation as porous-surfaced titanium plates into the cortical bone of the rabbit tibia. Bone ingrowth was evaluated by their implantation as cylindrical porous titanium implants into the cancellous bone of the rabbit femur for 2, 4, and 8 weeks. The average pore sizes of the P300, P600, and P900 implants were 309, 632, and 956 μm, respectively. The P600 implant demonstrated a significantly higher fixation ability at 2 weeks than the other implants. After 4 weeks, all models had sufficiently high fixation ability in a detaching test. Bone ingrowth into the P300 implant was lower than into the other implants at 4 weeks. Because of its appropriate mechanical strength, high fixation ability, and rapid bone ingrowth, our results indicate that the pore structure of the P600 implant is a suitable porous structure for orthopedic implants manufactured by SLM. - Highlights: • We studied the effect of pore size on bone tissue in-growth in a rabbit in vivo model. • Titanium samples with 300/600/900 μm pore size in three-dimensionally controlled shapes were fabricated by additive manufacturing. • Samples were

  6. Perspectives of Orthopedic Surgeons on Racial/Ethnic Disparities in Care.

    Science.gov (United States)

    Adelani, Muyibat A; O'Connor, Mary I

    2017-08-01

    Racial/ethnic disparities in healthcare, including orthopedics, have been extensively documented. However, the level of knowledge among orthopedic surgeons regarding racial/ethnic disparities is unknown. The purpose of this study is to determine the views of orthopedic surgeons on (1) the extent of racial/ethnic disparities in orthopedic care, (2) patient and system factors that may contribute, and (3) the potential role of orthopedic surgeons in the reduction of disparities. Three hundred five members of the American Orthopaedic Association completed a survey to assess their knowledge of racial/ethnic disparities and their perceptions about the underlying causes. Twelve percent of respondents believe that patients often receive different care based on race/ethnicity in healthcare in general, while 9 % believe that differences exist in orthopedic care in general, 3 % believe that differences exist within their hospitals/clinics, and 1 % reported differences in their own practices. Despite this, 68 % acknowledge that there is evidence of disparities in orthopedic care. Fifty-one percent believe that a lack of insurance significantly contributes to disparities. Thirty-five percent believe that diversification of the orthopedic workforce would be a "very effective" strategy in addressing disparities, while 25 % percent believe that research would be "very effective" and 24 % believe that surgeon education would be "very effective." Awareness regarding racial/ethnic disparities in musculoskeletal care is low among orthopedic surgeons. Additionally, respondents were more likely to acknowledge disparities within the practices of others than their own. Increased diversity, research, and education may help improve knowledge of this problem.

  7. Value Added: the Case for Point-of-View Camera use in Orthopedic Surgical Education.

    Science.gov (United States)

    Karam, Matthew D; Thomas, Geb W; Taylor, Leah; Liu, Xiaoxing; Anthony, Chris A; Anderson, Donald D

    2016-01-01

    Orthopedic surgical education is evolving as educators search for new ways to enhance surgical skills training. Orthopedic educators should seek new methods and technologies to augment and add value to real-time orthopedic surgical experience. This paper describes a protocol whereby we have started to capture and evaluate specific orthopedic milestone procedures with a GoPro® point-of-view video camera and a dedicated video reviewing website as a way of supplementing the current paradigm in surgical skills training. We report our experience regarding the details and feasibility of this protocol. Upon identification of a patient undergoing surgical fixation of a hip or ankle fracture, an orthopedic resident places a GoPro® point-of-view camera on his or her forehead. All fluoroscopic images acquired during the case are saved and later incorporated into a video on the reviewing website. Surgical videos are uploaded to a secure server and are accessible for later review and assessment via a custom-built website. An electronic survey of resident participants was performed utilizing Qualtrics software. Results are reported using descriptive statistics. A total of 51 surgical videos involving 23 different residents have been captured to date. This includes 20 intertrochanteric hip fracture cases and 31 ankle fracture cases. The average duration of each surgical video was 1 hour and 16 minutes (range 40 minutes to 2 hours and 19 minutes). Of 24 orthopedic resident surgeons surveyed, 88% thought capturing a video portfolio of orthopedic milestones would benefit their education. There is a growing demand in orthopedic surgical education to extract more value from each surgical experience. While further work in development and refinement of such assessments is necessary, we feel that intraoperative video, particularly when captured and presented in a non-threatening, user friendly manner, can add significant value to the present and future paradigm of orthopedic surgical

  8. Pre: Surgical orthopedic pre-maxillary alignment in bilateral cleft lip and palate patient

    Directory of Open Access Journals (Sweden)

    Vijaya Prasad Kamavaram Ellore

    2012-01-01

    Full Text Available Pre-surgical orthopedic appliances are mainly used to retract and align the protruded and deviated pre-maxilla and to facilitate initial lip repair. This article presents a case report of a five year old male child patient with bilateral cleft lip and palate in whom a special custom made pre-surgical orthopedic appliance was delivered. Use of a special custom made presurgical orthopedic appliance for repositioning pre-maxilla in bilateral cleft lip and palate patient is discussed in this article.

  9. Gentamicin coating of nanotubular anodized titanium implant reduces implant-related osteomyelitis and enhances bone biocompatibility in rabbits

    Directory of Open Access Journals (Sweden)

    Liu D

    2017-07-01

    Full Text Available Denghui Liu,1,* Chongru He,2,* Zhongtang Liu,2 Weidong Xu2 1Department of Orthopedics, the 113 Military Hospital, Ningbo, 2Department of Orthopedics, Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Titanium and titanium alloy are widely used as orthopedic implants for their favorable mechanical properties and satisfactory biocompatibility. The aim of the present study was to investigate the antibacterial effect and bone cell biocompatibility of a novel implant made with nanotubular anodized titanium coated with gentamicin (NTATi-G through in vivo study in ­rabbits. The animals were divided into four groups, each receiving different kinds of implants, that is, NTATi-G, titanium coated with gentamicin (Ti-G, nanotubular anodized titanium uncoated with gentamicin (NTATi and titanium uncoated with gentamicin (Ti. The results showed that NTATi-G implant prevented implant-related osteomyelitis and enhanced bone biocompatibility in vivo. Moreover, the body temperature of rabbits in NTATi-G and Ti-G groups was lower than those in Ti groups, while the weight of rabbits in NTATi-G and Ti-G groups was heavier than those in NTATi and Ti groups, respectively. White blood cell counts in NTATi-G group were lower than NTATi and Ti groups. Features of myelitis were observed by X-ray films in the NTATi and Ti groups, but not in the NTATi-G and Ti-G groups. The radiographic scores, which assessed pathology and histopathology in bone tissues, were significantly lower in the NTATi-G and Ti-G groups than those in the NTATi and Ti groups, respectively (P<0.05. Meanwhile, explants and bone tissue culture demonstrated significantly less bacterial growth in the NTATi-G and Ti-G groups than in the NTATi and Ti groups, respectively (P<0.01. The bone volume in NTATi-G group was greater than Ti-G group, and little bone formation was seen in NTATi and Ti

  10. High energy P implants in silicon

    International Nuclear Information System (INIS)

    Raineri, V.; Cacciato, A.; Benyaich, F.; Priolo, F.; Rimini, E.; Galvagno, G.; Capizzi, S.

    1992-01-01