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Sample records for biodegradable bone fixation

  1. Self-dissolution assisted coating on magnesium metal for biodegradable bone fixation devices

    Science.gov (United States)

    Khakbaz, Hadis; Walter, Rhys; Gordon, Timothy; Bobby Kannan, M.

    2014-12-01

    An attempt was made to develop a self-dissolution assisted coating on a pure magnesium metal for potential bone fixation implants. Magnesium phosphate cement (MPC) was coated successfully on the magnesium metal in ammonium dihydrogen phosphate solution. The in vitro degradation behaviour of the MPC coated metal was evaluated using electrochemical techniques. The MPC coating increased the polarisation resistance (RP) of the metal by ˜150% after 2 h immersion in simulated body fluid (SBF) and reduced the corrosion current density (icorr) by ˜80%. The RP of the MPC coated metal remained relatively high even after 8 h immersion period. However, post-degradation analysis of the MPC coated metal revealed localized attack. Hence, the study suggests that MPC coating alone may not be beneficial, but this novel coating could provide additional protection if used as a precursor for other potential coatings such as biodegradable polymers or calcium phosphates.

  2. Self-dissolution assisted coating on magnesium metal for biodegradable bone fixation devices

    International Nuclear Information System (INIS)

    An attempt was made to develop a self-dissolution assisted coating on a pure magnesium metal for potential bone fixation implants. Magnesium phosphate cement (MPC) was coated successfully on the magnesium metal in ammonium dihydrogen phosphate solution. The in vitro degradation behaviour of the MPC coated metal was evaluated using electrochemical techniques. The MPC coating increased the polarisation resistance (RP) of the metal by ∼150% after 2 h immersion in simulated body fluid (SBF) and reduced the corrosion current density (icorr) by ∼80%. The RP of the MPC coated metal remained relatively high even after 8 h immersion period. However, post-degradation analysis of the MPC coated metal revealed localized attack. Hence, the study suggests that MPC coating alone may not be beneficial, but this novel coating could provide additional protection if used as a precursor for other potential coatings such as biodegradable polymers or calcium phosphates. (paper)

  3. Biomechanical Comparison Between Bashti Bone Plug Technique and Biodegradable Screw for Fixation of Grafts in Ligament surgery

    OpenAIRE

    Kaveh Bashti; Mohammad Naghi Tahmasebi; Hasan Kaseb; Farzam Farahmand; Mohammad Akbar; Amir Mobini

    2015-01-01

      Background: Ligament reconstruction is a common procedure in orthopedic surgery. Although several popular techniques are currently in use, new methods are proposed for secure fixation of the tendon graft into the bone tunnel. Purposes: We sought to introduce our new technique of Bashti bone plug for fixation of soft tissue graft in anterior cruciate ligament (ACL) reconstruction and to compare its biomechanical features with conventional absorbable interference screw technique in a bovine ...

  4. Biomechanical Comparison Between Bashti Bone Plug Technique and Biodegradable Screw for Fixation of Grafts in Ligament surgery

    Directory of Open Access Journals (Sweden)

    Kaveh Bashti

    2015-01-01

    Full Text Available   Background: Ligament reconstruction is a common procedure in orthopedic surgery. Although several popular techniques are currently in use, new methods are proposed for secure fixation of the tendon graft into the bone tunnel. Purposes: We sought to introduce our new technique of Bashti bone plug for fixation of soft tissue graft in anterior cruciate ligament (ACL reconstruction and to compare its biomechanical features with conventional absorbable interference screw technique in a bovine model. Methods: Twenty pairs of bovine knees were harvested after death. Soft tissue was removed and the Achilles tendon was harvested to be used as an ACL graft. It was secured into the bone tunnel on the tibial side via two different methods: Bashti Bone Plug technique and conventional screw method. Biomechanical strength was measured using 200 N and 300 N cyclic loading on the graft. Pull out strength was also tested until the graft fails. Results: No graft failure was observed after 200 N and 300 N cyclic loading in either fixation methods. When testing for pull out failure, 21 tendons (53% were torn and 19 tendons (48% slipped out. No fixation failure occurred, which did not reveal a significant difference between the bone plug or interference screw group (P=0.11. The mean pull out force until failure of the graft was 496±66 N in the screw group and 503±67 N in the bone plug group (P=0.76. Conclusions: Our suggested fixation technique of Bashti bone plug is a native, cheap, and feasible method that provides comparable biomechanical strength with interference screw when soft tissue fixation was attempted in bovine model.

  5. Periprosthetic fracture fixation in osteoporotic bone.

    Science.gov (United States)

    Lenz, Mark; Lehmann, Wolfgang; Wähnert, Dirk

    2016-06-01

    Fixation techniques of periprosthetic fractures are far from ideal although the number of this entity is rising. The presence of an intramedullary implant generates its own fracture characteristics since stiffness is altered along the bone shaft and certain implant combinations affect load resistance of the bone. Influencing factors are cement fixation of the implant, intramedullary locking and extramedullary or intramedullary localization of the implant and the cortical thickness of the surrounding bone. Cerclage wires are ideally suited to fix radially displaced fragments around an intramedullary implant but they are susceptible to axial and torsional load. Screws should be added if these forces have to be neutralized. Stability of the screw fixation itself can be enhanced by embracement configuration around the intramedullary implant. Poor bone stock quality, often being present in metaphyseal areas limits screw fixation. Cement augmentation is an attractive option in this field to enhance screw purchase. PMID:27338227

  6. A new concept for implant fixation: bone-to-bone biologic fixation

    OpenAIRE

    D-Y Kim; J-R Kim; KY Jang; K-B Lee

    2015-01-01

    Many attempts have been made to reduce complications of bone implant, such as pedicle screw loosening. To address this problem, the authors suggest a new concept of bone-to-bone biologic fixation using recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded cannulated pedicle screws. Recombinant human bone morphogenetic protein-2 is an osteoinductive cytokine. Four types of titanium pedicle screws were tested (uncannulated, cannulated with no loading, beta-tricalcium phosphate (TCP)-l...

  7. A new concept for implant fixation: bone-to-bone biologic fixation.

    Science.gov (United States)

    Kim, D-Y; Kim, J-R; Jang, K Y; Lee, K-B

    2015-01-01

    Many attempts have been made to reduce complications of bone implant, such as pedicle screw loosening. To address this problem, the authors suggest a new concept of bone-to-bone biologic fixation using recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded cannulated pedicle screws. Recombinant human bone morphogenetic protein-2 is an osteoinductive cytokine. Four types of titanium pedicle screws were tested (uncannulated, cannulated with no loading, beta-tricalcium phosphate (TCP)-loaded, and TCP/BMP2 loaded) using 16 miniature pigs. Radiological evaluation was conducted to assess the fusion and loosening of pedicle screws. Twelve weeks after implantation, peak torsional extraction torque was measured, and the pedicle screw and bone interface was evaluated by micro-computed tomography (µCT) and histologic examination. The mean value of the radiological score was significantly greater in the TCP/BMP2 loaded group at 12 weeks post-operation compared to those in the other groups. CT images showed distinct bone formation surrounding TCP/BMP2 loaded cannulated pedicle screws compared to the other groups. Mean extraction torsional peak torque at 12 weeks postoperative was more than 10-fold higher in the TCP/BMP2 loaded pedicle screw group than in the other groups. Bone surface and bone volume, as quantitated through µCT, were higher in the TCP/BMP2 loaded group. Histologic examination revealed bone-to-bone fixation at the interface of pedicle screws and pre-existing bone. Bone-to-bone biologic fixation through the holes of TCP/BMP2 loaded pedicle screws significantly increased fixation strength and represents a novel method that can be applied to osteoporotic or tumour spine surgeries. PMID:25978116

  8. A new concept for implant fixation: bone-to-bone biologic fixation

    Directory of Open Access Journals (Sweden)

    D-Y Kim

    2015-05-01

    Full Text Available Many attempts have been made to reduce complications of bone implant, such as pedicle screw loosening. To address this problem, the authors suggest a new concept of bone-to-bone biologic fixation using recombinant human bone morphogenetic protein-2 (rhBMP-2-loaded cannulated pedicle screws. Recombinant human bone morphogenetic protein-2 is an osteoinductive cytokine. Four types of titanium pedicle screws were tested (uncannulated, cannulated with no loading, beta-tricalcium phosphate (TCP-loaded, and TCP/BMP2 loaded using 16 miniature pigs. Radiological evaluation was conducted to assess the fusion and loosening of pedicle screws. Twelve weeks after implantation, peak torsional extraction torque was measured, and the pedicle screw and bone interface was evaluated by micro-computed tomography (µCT and histologic examination. The mean value of the radiological score was significantly greater in the TCP/BMP2 loaded group at 12 weeks post-operation compared to those in the other groups. CT images showed distinct bone formation surrounding TCP/BMP2 loaded cannulated pedicle screws compared to the other groups. Mean extraction torsional peak torque at 12 weeks postoperative was more than 10-fold higher in the TCP/BMP2 loaded pedicle screw group than in the other groups. Bone surface and bone volume, as quantitated through µCT, were higher in the TCP/BMP2 loaded group. Histologic examination revealed bone-to-bone fixation at the interface of pedicle screws and pre-existing bone. Bone-to-bone biologic fixation through the holes of TCP/BMP2 loaded pedicle screws significantly increased fixation strength and represents a novel method that can be applied to osteoporotic or tumour spine surgeries.

  9. Clinical and radiographic evaluation of biodegradable bone plates in the treatment of mandibular body fractures

    Directory of Open Access Journals (Sweden)

    Sherin Kamal Elhalawany

    2015-01-01

    Full Text Available Background: Many different systems are available for the treatment of fractures ranging from the heavy compression plates for mandibular reconstruction to low profile plates for mid-facial fixation, and are made either from stainless steel, titanium or vitallium. Recently, biodegradable, self-reinforced polylactide plates and screws have been used for the internal fixation of fractures of the mandible with good results. Aim of this study: This study evaluated clinically the biodegradable bone plates for treatment of mandibular body fracture and to evaluate bone healing during the follow-up period using digital radiography. Materials and Methods : Eight patients had been suffered from mandibular body fractures were treated using Inion CPS TM bioresorbable fixation system and the healing process were followed up using digitised panoramic radiography at first week and after 1, 3 and 6 months. Results: Clinical examination of fractured segments revealed stable fixation across the fracture sites while visual and quantitative assessment of radiograph showed healing process was comparable with results previously reported by titanium bone plates. Conclusion: Open reduction and internal fixation of mandibular fractures using bioresorbable fixation system with a brief period of inter-maxillary fixation have evolved to the point where the physical properties are sufficient to withstand the post-operative loads required for fracture repair of mandibular body fractures. The foreign body reaction is a major material-related problem which requires further studies.

  10. Use of polymethylmethacrylate to enhance screw fixation in bone.

    Science.gov (United States)

    Cameron, H U; Jacob, R; Macnab, I; Pilliar, R M

    1975-07-01

    Pull-out testing of screws inserted into cement and bone under various conditions showed that the cement-screw complex was significantly stronger when the screw was placed in soft cement and the cement was allowed to polymerize without further manipulation. When screw fixation in osteoporotic bone was reinforced with cement, the bone was the weakest component in the system. Fixation under these conditions should be enhanced by increasing the area of contact between the cement and bone. By cooling the cement to prolong its working time, it could be injected with a syringe in such a way that maximum endosteal and periosteal contact was provided. PMID:1150708

  11. Fixation of tibial plateau fractures with synthetic bone graft versus natural bone graft: a comparison study.

    LENUS (Irish Health Repository)

    Ong, J C Y

    2012-06-01

    The goal of this study was to determine differences in fracture stability and functional outcome between synthetic bone graft and natural bone graft with internal fixation of tibia plateau metaphyseal defects.

  12. Bone graft materials in fixation of orthopaedic implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan

    2013-01-01

    bone and includes bone collagen, morphogenetic proteins and growth factors. The combination of DBM with CB and with allograft might improve the healing potential of these grafts around non-cemented orthopaedic implants and thereby the implant fixation. Study I investigates the effect of HA...

  13. A biomechanical comparison between cortical bone trajectory fixation and pedicle screw fixation

    OpenAIRE

    Oshino, Hiroki; Sakakibara, Toshihiko; Inaba, Tadashi; Yoshikawa, Takamasa; Kato, Takaya; Kasai, Yuichi

    2015-01-01

    Purpose There have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method. The purpose of this study was to compare vertebral stability after CBT fixation with that after pedicle screw (PS) fixation. Methods In this study, 20 lumbar spine (L5–6) specimens were assigned to two groups: the CBT model group that underwent CBT screw fixation (n = 10) and the PS model group t...

  14. Study on the Algorithm of Multifunctional Bone External Fixator

    Directory of Open Access Journals (Sweden)

    Chen Jianwen

    2015-01-01

    Full Text Available This paper discussed the problem that parameters of bone external fixator are difficult to calculate in the practical application. Positive solution is described in detail. We used MATLAB software to make simulation experiment. The innovation lies the development idea of using inverse position to verify the accuracy of positive solution. Forward displacement analysis was mainly developed using analytical method, which has many advantages, such as small dependence to the inverse solution and the higher precision. With further software development, we will have the algorithms; research model and interface program connected and form high precision smart compliance multifunctional bone external fixator products, which will greatly enhance the overall level of bone external fixation technology and clinical application treatment.

  15. Joint prosthesis and method of bone fixation

    OpenAIRE

    Oosterom, R; Pijl, A J; Bersee, H.E.N.; Van der Helm, F.C.; Herder, J. L.

    2006-01-01

    The invention relates to a joint prosthesis (10), for example, a knee joint or shoulder joint prosthesis comprising a first, socket-holding prosthesis part (11) for attachment to a first bone (12) and a second, ball-holding prosthesis part (13) for attachment to a second bone (14) that intermates with the first prosthesis part, wherein the first bone and the second bone are situated at either side of a joint, and wherein the ball (2) of the second prosthesis part is rotatably received in the ...

  16. Bone compaction enhances implant fixation in a canine gap model

    DEFF Research Database (Denmark)

    Kold, Søren; Rahbek, Ole; Toft, Marianne;

    2005-01-01

    A new bone preparation technique, compaction, has increased fixation of implants inserted with exact-fit or press-fit to bone. Furthermore, a demonstrated spring-back effect of compacted bone might be of potential value in reducing the initial gaps that often exist between clinical inserted...... implants and bone. However, it is unknown whether the compression and breakage of trabeculae during the compaction procedure results in impaired gap-healing of compacted bone. Therefore, we compared compaction with conventional drilling in a canine gap model. Grit-blasted titanium implants (diameter 6 mm...... that the beneficial effect of reduced gap size, as compacted bone springs back, is not eliminated by an impaired gap-healing of compacted bone....

  17. Inadvertent Screw Stripping During Ankle Fracture Fixation in Elderly Bone

    OpenAIRE

    Dinah, A. Feroz; Mears, Simon C.; Knight, Trevor A.; Soin, Sandeep P.; Campbell, John T.; Belkoff, Stephen M.

    2011-01-01

    Poor screw purchase because of osteoporosis presents difficulties in ankle fracture fixation. The aim of our study was to determine if cortical thickness, unicortical versus bicortical purchase, and bone mineral density are predictors of inadvertent screw stripping and overtightening. Ten paired cadaver ankles (average donor age, 81.7 years; range, 50-97 years) were used for the study. Computed tomography scanning with phantoms of known density was used to determine the bone density along the...

  18. Joint prosthesis and method of bone fixation

    NARCIS (Netherlands)

    Oosterom, R.; Van der Pijl, A.J; Bersee, H.E.N.; Van der Helm, F.C.; Herder, J.L

    2006-01-01

    The invention relates to a joint prosthesis (10), for example, a knee joint or shoulder joint prosthesis comprising a first, socket-holding prosthesis part (11) for attachment to a first bone (12) and a second, ball-holding prosthesis part (13) for attachment to a second bone (14) that intermates wi

  19. Biodegradable Polymers in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Leon E. Govaert

    2009-07-01

    Full Text Available The use ofdegradable polymers in medicine largely started around the mid 20th century with their initial use as in vivo resorbing sutures. Thorough knowledge on this topic as been gained since then and the potential applications for these polymers were, and still are, rapidly expanding. After improving the properties of lactic acid-based polymers, these were no longer studied only from a scientific point of view, but also for their use in bone surgery in the 1990s. Unfortunately, after implanting these polymers, different foreign body reactions ranging from the presence of white blood cells to sterile sinuses with resorption of the original tissue were observed. This led to the misconception that degradable polymers would, in all cases, lead to inflammation and/or osteolysis at the implantation site. Nowadays, we have accumulated substantial knowledge on the issue of biocompatibility of biodegradable polymers and are able to tailor these polymers for specific applications and thereby strongly reduce the occurrence of adverse tissue reactions. However, the major issue of biofunctionality, when mechanical adaptation is taken into account, has hitherto been largely unrecognized. A thorough understanding of how to improve the biofunctionality, comprising biomechanical stability, but also visualization and sterilization of the material, together with the avoidance of fibrotic tissue formation and foreign body reactions, may greatly enhance the applicability and safety of degradable polymers in a wide area of tissue engineering applications. This review will address our current understanding of these biofunctionality factors, and will subsequently discuss the pitfalls remaining and potential solutions to solve these problems.

  20. Bone resorption around pedicle screws after pedicle screw plate fixation

    International Nuclear Information System (INIS)

    To determine the frequency, level, distribution, onset, and pattern of progression of bone resorption that occurring around pedicle screws after pedicle screw plate fixation. Bone resorption around 902 pedicle screws was analyzed in post-operative, and follow-up radiographs obtained from 156 patients who underwent pedicle screw plate fixation. To determine the resorption degree, categorized arbitrarily as grade 1 (less than 1 mm), grade 2 (1mm or more, but less than 2 mm), or grade 3 (2mm or more), the width of radiolucent zones was measured. In 39 patients in whom resorption was graded 1, 2 or 3, the pattern of progression of 78 screws was evaluated. Resorption occurred around 78 (8.6%) screws in 39 (25%) patients, 26 of whom had more than on lesion. For 99% of screws, there was evidance of resorption within 12 weeks of pedicle screw plate fixation. During follow-up, 61.5% of screws (48/78) remained stable, while 38.5% (30 screws) showed progression to higher grades. The possibility of progression to a higher grade is less when the initial grade is lower. An understanding of the radiographic patterns of bone resorption is useful for monitoring a patient after pedicle screw plate fixation

  1. Nitrogen limitation and nitrogen fixation during alkane biodegradation in a sandy soil.

    OpenAIRE

    Toccalino, P L; Johnson, R L; Boone, D.R.

    1993-01-01

    We investigated nutrient limitations during hydrocarbon degradation in a sandy soil and found that fixed nitrogen was initially a limiting nutrient but that N limitation could sometimes be overcome by N2 fixation. Hydrocarbon biodegradation was examined in an unsaturated sandy soil incubated aerobically at 20 degrees C with propane or butane and various added nutrients. Propane and butane degradation proceeded similarly during the first 3 months of incubation. That is, bacteria in soil amende...

  2. Study on the Algorithm of Multifunctional Bone External Fixator

    OpenAIRE

    Chen Jianwen; Shi Xuewei; Wei Mengting; Sun Hao

    2015-01-01

    This paper discussed the problem that parameters of bone external fixator are difficult to calculate in the practical application. Positive solution is described in detail. We used MATLAB software to make simulation experiment. The innovation lies the development idea of using inverse position to verify the accuracy of positive solution. Forward displacement analysis was mainly developed using analytical method, which has many advantages, such as small dependence to the inverse solution and t...

  3. Demineralized bone matrix and human cancellous bone enhance fixation of titanium implants

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    produced from human tissue were included (IsoTis OrthoBiologics, Inc. USA). Both materials are commercially available. Titanium alloy implants (Biomet Inc.) of 10 mm in length and 10 mm in diameter were inserted bilaterally into the femoral condyles of 8 skeletally mature sheep. Thus four implants with a......Best Poster 5Demineralized bone matrix and human cancellous bone enhance fixation of titanium implants AuthorsBabiker , H.; Ding M.; Overgaard S.InstitutionOrthopaedic Research Laboratory, Department of Orthopaedic Surgery, Odense University Hospital, Clinical Institute, University of Southern......- and autograf as they have the capability of inducing new bone and improving implant fixation through enhancing bone ingrowth. The purpose of this study was to investigate the effect of DBM alone or with CB on the fixation of porous-coated titanium implants.Material and MethodsDBM100 (pure DBM) and CB...

  4. APPLICATION OF A BIODEGRADABLE MATERIAL FOR BONE REPLACEMENT IN TRAUMATOLOGY

    Directory of Open Access Journals (Sweden)

    T. V. Druzhinina

    2014-01-01

    Full Text Available 20 men (medium age (31.5 ± 13.5 years were studied. All patients underwent arthroscopic auditing plastic anterior cruciate ligament of the knee. Osteoregeneration dynamics were determined by biochemical testing of blood serum and X-ray computed tomography (CT of the fracture in 1–4 months after surgery. As a result, an estimation of the bone tissue reparative regeneration according to CT data in 10 patients with a defect of the patella, treated with the material is provided. The obtained results of the clinical study indicate the reparative effect of the biodegradable material for bone replacing on bone regeneration

  5. Biodegradable and semi-biodegradable composite hydrogels as bone substitutes: morphology and mechanical characterization.

    Science.gov (United States)

    Sanginario, V; Ginebra, M P; Tanner, K E; Planell, J A; Ambrosio, L

    2006-05-01

    Biodegradable and semi-biodegradable composite hydrogels are proposed as bone substitutes. They consist of an hydrophilic biodegradable polymer (HYAFF 11) as matrix and two ceramic powders (alpha-TCP and HA) as reinforcement. Both components of these composites have been of great interest in biomedical applications due to their excellent biocompatibility and tissue interactions, however they have never been investigated as bone substitute composites. Morphological and mechanical analysis have shown that the two fillers behave in a very different way. In the HYAFF 11/alpha-TCP composite, alpha-TCP is able to hydrolyze in contact with water while in the HYAFF 11 matrix. As a result, the composite sets and hardens, and entangled CDHA crystals are formed in the hydrogel phase and increases in the mechanical properties are obtained. In the HYAFF11/HA composite the ceramic reinforcement acts as inert phase leading to lower mechanical properties. Both mechanical properties and microstructure analysis have demonstrated the possibility to design hydrophilic biodegradable composite structures for bone tissue substitution applications. PMID:16688585

  6. Development of a Three-Dimensional (3D) Printed Biodegradable Cage to Convert Morselized Corticocancellous Bone Chips into a Structured Cortical Bone Graft

    Science.gov (United States)

    Chou, Ying-Chao; Lee, Demei; Chang, Tzu-Min; Hsu, Yung-Heng; Yu, Yi-Hsun; Liu, Shih-Jung; Ueng, Steve Wen-Neng

    2016-01-01

    This study aimed to develop a new biodegradable polymeric cage to convert corticocancellous bone chips into a structured strut graft for treating segmental bone defects. A total of 24 adult New Zealand white rabbits underwent a left femoral segmental bone defect creation. Twelve rabbits in group A underwent three-dimensional (3D) printed cage insertion, corticocancellous chips implantation, and Kirschner-wire (K-wire) fixation, while the other 12 rabbits in group B received bone chips implantation and K-wire fixation only. All rabbits received a one-week activity assessment and the initial image study at postoperative 1 week. The final image study was repeated at postoperative 12 or 24 weeks before the rabbit scarification procedure on schedule. After the animals were sacrificed, both femurs of all the rabbits were prepared for leg length ratios and 3-point bending tests. The rabbits in group A showed an increase of activities during the first week postoperatively and decreased anterior cortical disruptions in the postoperative image assessments. Additionally, higher leg length ratios and 3-point bending strengths demonstrated improved final bony ingrowths within the bone defects for rabbits in group A. In conclusion, through this bone graft converting technique, orthopedic surgeons can treat segmental bone defects by using bone chips but with imitate characters of structured cortical bone graft. PMID:27104525

  7. Development of a Three-Dimensional (3D) Printed Biodegradable Cage to Convert Morselized Corticocancellous Bone Chips into a Structured Cortical Bone Graft.

    Science.gov (United States)

    Chou, Ying-Chao; Lee, Demei; Chang, Tzu-Min; Hsu, Yung-Heng; Yu, Yi-Hsun; Liu, Shih-Jung; Ueng, Steve Wen-Neng

    2016-01-01

    This study aimed to develop a new biodegradable polymeric cage to convert corticocancellous bone chips into a structured strut graft for treating segmental bone defects. A total of 24 adult New Zealand white rabbits underwent a left femoral segmental bone defect creation. Twelve rabbits in group A underwent three-dimensional (3D) printed cage insertion, corticocancellous chips implantation, and Kirschner-wire (K-wire) fixation, while the other 12 rabbits in group B received bone chips implantation and K-wire fixation only. All rabbits received a one-week activity assessment and the initial image study at postoperative 1 week. The final image study was repeated at postoperative 12 or 24 weeks before the rabbit scarification procedure on schedule. After the animals were sacrificed, both femurs of all the rabbits were prepared for leg length ratios and 3-point bending tests. The rabbits in group A showed an increase of activities during the first week postoperatively and decreased anterior cortical disruptions in the postoperative image assessments. Additionally, higher leg length ratios and 3-point bending strengths demonstrated improved final bony ingrowths within the bone defects for rabbits in group A. In conclusion, through this bone graft converting technique, orthopedic surgeons can treat segmental bone defects by using bone chips but with imitate characters of structured cortical bone graft. PMID:27104525

  8. Autologous bone graft versus demineralized bone matrix in internal fixation of ununited long bones

    Directory of Open Access Journals (Sweden)

    Rubenbauer Bianka

    2009-12-01

    Full Text Available Abstract Background Non-unions are severe complications in orthopaedic trauma care and occur in 10% of all fractures. The golden standard for the treatment of ununited fractures includes open reduction and internal fixation (ORIF as well as augmentation with autologous-bone-grafting. However, there is morbidity associated with the bone-graft donor site and some patients offer limited quantity or quality of autologous-bone graft material. Since allogene bone-grafts are introduced on the market, this comparative study aims to evaluate healing characteristics of ununited bones treated with ORIF combined with either iliac-crest-autologous-bone-grafting (ICABG or demineralized-bone-matrix (DBM. Methods and results From 2000 to 2006 out of sixty-two consecutive patients with non-unions presenting at our Level I Trauma Center, twenty patients had ununited diaphyseal fractures of long bones and were treated by ORIF combined either by ICABG- (n = 10 or DBM-augmentation (n = 10. At the time of index-operation, patients of the DBM-group had a higher level of comorbidity (ASA-value: p = 0.014. Mean duration of follow-up was 56.6 months (ICABG-group and 41.2 months (DBM-group. All patients were clinically and radiographically assessed and adverse effects related to bone grafting were documented. The results showed that two non-unions augmented with ICABG failed osseous healing (20% whereas all non-unions grafted by DBM showed successful consolidation during the first year after the index operation (p = 0.146. No early complications were documented in both groups but two patients of the ICABG-group suffered long-term problems at the donor site (20% (p = 0.146. Pain intensity were comparable in both groups (p = 0.326. However, patients treated with DBM were more satisfied with the surgical procedure (p = 0.031. Conclusion With the use of DBM, the costs for augmentation of the non-union-site are more expensive compared to ICABG (calculated difference: 160

  9. Mathematical simulation of the biomechanical system bone-fixator

    Science.gov (United States)

    Krasnoschekov, Viktor V.; Maslov, Leonid B.

    2001-02-01

    Problems of static and dynamic simulation of the biomechanical system consisting of the human tibia bone and external fixator apparatus as the simplest frame construction are considered. The finite element method implemented as the program code MechanicsFE3D_ESO on the basis of 20 nodal isoparametric elements is utilized. Both general stressed-deformed state of the construction under transversal loading and basic frequencies and forms of free oscillations of the system were defined by the numerical analysis. The results obtained can be used as the theoretical fundament to developing of static and vibration resonance methods for physiological state diagnostics of the regenerating osseous tissue in fracture zone.

  10. Biodegradable nanocomposite coatings accelerate bone healing: In vivo evaluation

    OpenAIRE

    Mehdi Mehdikhani-Nahrkhalaji; Mohammad Hossein Fathi; Vajihesadat Mortazavi; Sayed Behrouz Mousavi; Ali Akhavan; Abbas Haghighat; Batool Hashemi-Beni; Sayed Mohammad Razavi; Fatemeh Mashhadiabbas

    2015-01-01

    Background: The aim of this study was to evaluate the interaction of bioactive and biodegradable poly (lactide-co-glycolide)/bioactive glass/hydroxyapatite (PBGHA) and poly (lactide-co-glycolide)/bioactive glass (PBG) nanocomposite coatings with bone. Materials and Methods: Sol-gel derived 58S bioactive glass nanoparticles, 50/50 wt% poly (lactic acid)/poly (glycolic acid) and hydroxyapatite nanoparticles were used to prepare the coatings. The nanocomposite coatings were characterized by ...

  11. Biodegradable Polymer-Based Scaffolds for Bone Tissue Engineering

    CERN Document Server

    Sultana, Naznin

    2013-01-01

    This book addresses the principles, methods and applications of biodegradable polymer based scaffolds for bone tissue engineering. The general principle of bone tissue engineering is reviewed and the traditional and novel scaffolding materials, their properties and scaffold fabrication techniques are explored. By acting as temporary synthetic extracellular matrices for cell accommodation, proliferation, and differentiation, scaffolds play a pivotal role in tissue engineering. This book does not only provide the comprehensive summary of the current trends in scaffolding design but also presents the new trends and directions for scaffold development for the ever expanding tissue engineering applications.

  12. Biodegradable Polymers in Bone Tissue Engineering

    OpenAIRE

    Govaert, Leon E.; Smit, Theo H; Robert J. Kroeze; Helder, Marco N.

    2009-01-01

    The use ofdegradable polymers in medicine largely started around the mid 20th century with their initial use as in vivo resorbing sutures. Thorough knowledge on this topic as been gained since then and the potential applications for these polymers were, and still are, rapidly expanding. After improving the properties of lactic acid-based polymers, these were no longer studied only from a scientific point of view, but also for their use in bone surgery in the 1990s. Unfortunately, after implan...

  13. Press-fit Femoral Fixation in ACL Reconstruction using Bone-Patellar Tendon-Bone Graft

    Directory of Open Access Journals (Sweden)

    Kaseb Mohammad Hasan

    2009-05-01

    Full Text Available Bone-patellar tendon auto graft is probably the most widely used graft for ACL reconstruction. Several methods for graft fixation have been described. To avoid intra-articular hardware we adopt biological fixation with a femoral trapezoidal press-fit fixation. A prospective study was performed on 30 consecutive active people who underwent ACL reconstruction with this technique by two surgeons between september2004 and march2007 (mean follow-up 15.2 months. Results were evaluated by an independent examiner using radiography, subjective and objective evaluation. Assessment using the IKDC knee scoring revealed 92% of the patients with a normal or nearly normal knee joint. Lysholm's score was 63.6(40- 86 preoperatively and 91.88(73-100 at the latest follow up (P < 0.005. No patient complained of instability at latest follow up. The quadriceps muscle showed mild atrophy at 3 and 6 months and at final follow-up. Five Patients complained of anterior knee pain and had a positive kneeling test. We found no graft displacement on follow up radiographs. All cases showed radiological evidence of graft osteointegration at last follow up. Our results show that press-fit fixation of trapezoidal bone graft in femoral tunnel is a simple, reliable, and cost-effective alternative for ACL recon-struction using bone-patellar tendon-bone graft.

  14. Bone compaction enhances fixation of weightbearing titanium implants

    DEFF Research Database (Denmark)

    Kold, Søren Vedding; Rahbek, Ole; Vestermark, Marianne Toft; Overgaard, Søren; Søballe, Kjeld

    2005-01-01

    weightbearing, the effects of compaction on weightbearing implants were examined. The hypothesis was that compaction would increase implant fixation compared with conventional drilling. Porous-coated titanium implants were inserted bilaterally into the weightbearing portion of the femoral condyles of dogs. In...... each dog, one knee had the implant cavity prepared with drilling, and the other knee was prepared with compaction. Eight dogs were euthanized after 2 weeks, and eight dogs were euthanized after 4 weeks. Femoral condyles from an additional eight dogs represented Time 0. Compacted specimens had higher...... bone-implant contact and periimplant bone density at 0 and 2 weeks, but not at 4 weeks. A biphasic response of compaction was found with a pushout test, as compaction increased ultimate shear strength and energy absorption at 0 and 4 weeks, but not at 2 weeks. This biphasic response indicates that...

  15. Treatment of tibial defect and bone nonunion with limb shortening with external fixator and reconstituted bone xenograft

    Institute of Scientific and Technical Information of China (English)

    王志刚; 刘建; 胡蕴玉; 孟国林; 金格勒; 袁志; 王海强; 戴先文

    2003-01-01

    Objective: To explore the effect of external fixator and reconstituted bone xenograft (RBX) in the treatment of tibial bone defect, tibial bone nonunion and congenital pseudarthrosis of the tibia with limb shortening. Methods: Twenty patients ( 13 males and 7 females) with tibial bone defect, tibial bone nonunion or congenital pseudarthrosis of the tibia with limb shortening were treated with external fixation. Two kinds of external fixators were used: a half ring sulcated external fixator used in 13 patients and a combined external fixator in 7 patients. Foot-drop was corrected at the same time with external fixation in 4 patients. The shortened length of the tibia was in the range of 2-9 cm, with an average of 4.8 cm. For bone grafting, RBX was used in 12 patients, autogenous ilium was used in 3 patients and autogenous fibula was implanted as a bone plug into the medullary canal in 1 case, and no bone graft was used in 4 patients. Results: All the 20 patients were followed-up for 8 months to 7 years, averaging 51 months. Satisfactory function of the affected extremities was obtained. All the shortened extremities were lengthened to the expected length. For all the lengthening area and the fracture sites, bone union was obtained at the last. The average healing time of 12 patients treated with RBX was 4.8 months. Conclusions: Both the half ring sulcated external fixator and the combined external fixator have the advantages of small trauma, simple operation, elastic fixation without stress shielding and non-limitation from local soft tissue conditions, and there is satisfactory functional recovery of affected extremities in the treatment of tibial bone defects, tibial bone nonunion and congenital pseudarthrosis of the tibia combined with limb shortening. RBX has good biocompatibility and does not cause immunological rejections. It can also be safely used in treatment of bone nonunion and has reliable effect to promote bone healing.

  16. Fragment reconstruction and bone plate fixation versus bridging plate fixation for treating highly comminuted femoral fractures in dogs: 35 cases (1987-1997)

    International Nuclear Information System (INIS)

    To compare fragment reconstruction and bone plate fixation versus bridging plate fixation for treating highly comminuted (> 4 fragments) femoral fractures in dogs. Retrospective study. 35 dogs with highly comminuted fractures of the femur. Medical records of all dogs included in this study were reviewed. Dogs had been treated with fragment reconstruction and bone plate application (n = 20) or major fragment alignment and bridging plate fixation (15). Postoperative and follow-up radiographs were evaluated. Operating and hospitalization times, bone alignment, bone healing, and complications were considered. There were no differences in hospitalization times, limb alignment, and complications between dogs with fractures treated with fragment reconstruction and dogs with fractures treated with bridging plate fixation. Dogs with fractures treated with bridging plate fixation had shorter operative times and faster times to radiographic evidence of bone healing. Bridging plate fixation is quicker to perform and results in faster healing than fragment reconstruction and bone plate fixation when used to treat comminuted femoral fractures

  17. Influence of different methods of internal bone fixation on characteristics of bone callus in experimental animals

    Directory of Open Access Journals (Sweden)

    Gajdobranski Đorđe

    2014-01-01

    Full Text Available Introduction. Correct choice of osteosynthesis method is a very important factor in providing the optimal conditions for appropriate healing of the fracture. There are still disagreements about the method of stabilization of some long bone fractures. Critically observed, no method of fracture fixation is ideal. Each osteosynthesis method has both advantages and weaknesses. Objective. The objective of this study was to compare the results of the experimental application of three different internal fixation methods: plate fixation, intramedullary nail fixation and self-dynamisable internal fixator (SIF. Methods. A series of 30 animals were used (Lepus cuniculus as experimental animals, divided into three groups of ten animals each. Femoral diaphysis of each animal was osteotomized and fixed with one of three implants. Ten weeks later all animals were sacrificed and each specimen underwent histological and biomechanical testing. Results. Histology showed that the healing process with SIF was more complete and bone callus was more mature in comparison to other two methods. During biomechanical investigation (computerized bending stress test, it was documented with high statistical significance that using SIF led to stronger healing ten weeks after the operation. Conclusion. According to the results obtained in this study, it can be concluded that SIF is a suitable method for fracture treatment.

  18. Unilateral Pedicle Screw Fixation with Bone Graft vs. Bilateral Pedicle Screw Fixation with Bone Graft or Cage: A Comparative Study.

    Science.gov (United States)

    Yang, Si-Dong; Chen, Qian; Ding, Wen-Yuan; Zhao, Jian-Qiang; Zhang, Ying-Ze; Shen, Yong; Yang, Da-Long

    2016-01-01

    BACKGROUND The aim of this study was to explore the clinical efficacy of unilateral pedicle screw fixation with bone graft (UPSFB) in treating single-segment lumbar degenerative diseases (LDD), as compared to bilateral pedicle screw fixation with bone graft (BPSFB) or with cage (BPSFC). MATERIAL AND METHODS Medical records were retrospectively collected between 01/2010 and 02/2015 in Longyao County Hospital. According to surgical methods used, all patients were divided into 3 groups: UPSFB group, BPSFB group, and BPSFC group. Clinical outcomes were evaluated by blood loss, blood transfusion, duration of operation, hospital stay, postoperative complications, interbody fusion rate, reoperation rate, medical expenses, patient satisfaction survey, and JOA score. RESULTS Ninety-five patients were included and underwent 2.5-year follow-up, with 7 patients lost to regular follow-up. As compared to the BPSFB group and BPSFC group, the UPSFB group had less blood loss and less blood transfusion, as well as shorter hospital stay (pfusion rate, reoperation rate, JOA score, and patient satisfaction (all p>0.05). CONCLUSIONS As compared to BPSFB and BPSFC, UPSFB has the same reliability and effectiveness in treating single-segment LDD with unilateral radicular symptoms in a single lower extremity, with the additional advantage being less expensive. PMID:26988532

  19. Unilateral Pedicle Screw Fixation with Bone Graft vs. Bilateral Pedicle Screw Fixation with Bone Graft or Cage: A Comparative Study

    Science.gov (United States)

    Yang, Si-Dong; Chen, Qian; Ding, Wen-Yuan; Zhao, Jian-Qiang; Zhang, Ying-Ze; Shen, Yong; Yang, Da-Long

    2016-01-01

    Background The aim of this study was to explore the clinical efficacy of unilateral pedicle screw fixation with bone graft (UPSFB) in treating single-segment lumbar degenerative diseases (LDD), as compared to bilateral pedicle screw fixation with bone graft (BPSFB) or with cage (BPSFC). Material/Methods Medical records were retrospectively collected between 01/2010 and 02/2015 in Longyao County Hospital. According to surgical methods used, all patients were divided into 3 groups: UPSFB group, BPSFB group, and BPSFC group. Clinical outcomes were evaluated by blood loss, blood transfusion, duration of operation, hospital stay, postoperative complications, interbody fusion rate, reoperation rate, medical expenses, patient satisfaction survey, and JOA score. Results Ninety-five patients were included and underwent 2.5-year follow-up, with 7 patients lost to regular follow-up. As compared to the BPSFB group and BPSFC group, the UPSFB group had less blood loss and less blood transfusion, as well as shorter hospital stay (p0.05). Conclusions As compared to BPSFB and BPSFC, UPSFB has the same reliability and effectiveness in treating single-segment LDD with unilateral radicular symptoms in a single lower extremity, with the additional advantage being less expensive. PMID:26988532

  20. Outcome of rail fixator system in reconstructing bone gap

    Directory of Open Access Journals (Sweden)

    Amit Lakhani

    2014-01-01

    Conclusion: All patients well tolerated rail fixator with good functional results and gap reconstruction. Easy application of rail fixator and comfortable distraction procedure suggest rail fixator a good alternative for gap reconstruction of limbs.

  1. The effects of bone marrow aspirate, bone graft, and collagen composites on fixation of titanium implants

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Sandri, Monica;

    2012-01-01

    marrow aspirate (BMA) on enhancement of bone implant fixation. Method: Titanium alloy implants were inserted into bilateral femoral condyles of eight skeletally mature sheep, four implants per sheep. The implant had a circumferential gap of 2 mm. The gap was filled with: HA/Collagen; HA......Replacement of extensive local bone loss especially in revision joint arthroplasty and spine fusion is a significant clinical challenge. Allograft and autograft have been considered as gold standards for bone replacement. However, there are several disadvantages such as donor site pain, bacterial...... contamination, and non union as well as the potential risk of disease transmission. Hydroxyapatite and collagen composites (HA/Collagen) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effects of newly developed HA/Collagen-composites with and without bone...

  2. Co-optimization of diesel fuel biodegradation and N2 fixation through the addition of particulate organic carbon

    International Nuclear Information System (INIS)

    Petroleum hydrocarbon pollution in the marine environment is widespread and current bioremedial techniques are often not cost effective for small spills. The formulation of simple and inexpensive bioremedial methods could help reduce the impacts of frequent low volume spills in areas like marinas and ports. Particulate organic carbon (POC) was added to diesel fuel amended samples from inshore marine waters in the form of corn-slash (post-harvest leaves and stems), with and without inorganic nutrients (nitrate and phosphate). Biodegradation of diesel fuel (14C hexadecane mineralization) and N2 fixation were measured in response to the additions, The addition of POC was necessary for N2 fixation and diesel fuel biodegradation to co-occur. The effects of diesel fuel and inorganic nutrient additions on N2 fixation rates were not consistent, with both inhibitory and stimulatory responses to each addition observed. The highest observed diesel fuel biodegradation levels were in response to treatments that included inorganic nutrients. The addition of POC alone increased diesel fuel degradation levels above that observed in the control. In an attempt to determine the effect of the POC on the microbial community, the corn particles were observed microscopically using scanning electron microscopy and light microscopy with tetrazolium salt additions. The corn particles were found to have abundant attached bacterial communities and microscale oxygen concentration gradients occurring on individual particles. The formation of oxygen replete microzones may be essential for the co-occurrence of aerobic diesel fuel biodegradation and oxygen inhibited N2 fixation. Mesocosm experiments are currently underway to further examine the structure and function of this primarily heterotrophic system and to explore the potential contribution of N2 fixation to the N requirements of diesel fuel biodegradation

  3. Combination of bone cement filling and plate internal fixation with limb salvage is used for metastatic malignant bone tumors☆

    Institute of Scientific and Technical Information of China (English)

    Yang Jun; Yu Bin; Guo Xin-hui; Yang Peng; Zhang Kai-rui; Zhang Sheng; Cai Wei-bin; Ku Jian-bin; Tian Ling-yan

    2013-01-01

    BACKGROUND:Currently, limb salvage therapy has become the standard treatment of malignant bone tumors way, but improper treatments wil result in tumor recurrence, secondary infection, internal fixation or prosthesis loosening. OBJECTIVE:Based on the traditional surgical principle for metastatic bone tumors of the limbs, this study designed a user-friendly, individualized, simplistic pal iative treatment regimen from the actual conditions of patients to observe the reasonability, clinical efficacy and prognosis of bone cement fil ing combined with internal fixation in the treatment of metastatic malignant bone tumors. METHODS:Thirty-one patients with metastatic malignant bone tumors who required salvage treatment were screened from the Department of Orthopedics, the 421 Hospital of Chinese PLA, and their clinical data were retrospectively analyzed. Al the 31 patients were divided into two groups:tumor removal+internal fixation group (non-chemoradiotherapy group, n=11) treated with bone cement fil ing plus plate internal fixation (pal iative treatment);tumor removal+internal fixation+chemoradiotherapy group (chemoradiotherapy group, n=20), treated with radiotherapy before internal fixation plus plate internal fixation with limb salvage. The fol ow-up period was 4-38 months, averagely 18 months. RESULTS AND CONCLUSION:The fol ow-up results showed that in the non-chemoradiotherapy group, al the 11 patients survived, who could live independently and have good motor functions;in the chemoradiotherapy group, 17 of the 20 patients survived and the rest three patients died of tumor metastasis, their poor conditions and complications at 9 and 13 months after internal fixation. In patients undergoing tumor removal+plate internal fixation with limb salvage, the integrated scores for nerve and motor functions were increased by more than level 1. These findings confirm that a simple pal iative therapy of bone cement fil ing and internal fixation without chemoradiotherapy is

  4. An in vivo evaluation of PLLA/PLLA-gHA nano-composite for internal fixation of mandibular bone fractures.

    Science.gov (United States)

    Peng, Weihai; Zheng, Wei; Shi, Kai; Wang, Wangshu; Shao, Ying; Zhang, Duo

    2015-12-01

    Internal fixation of bone fractures using biodegradable poly(L-lactic-acid) (PLLA)-based materials has attracted the attention of many researchers. In the present study, 36 male beagle dogs were randomly assigned to two groups: PLLA/PLLA-gHA (PLLA-grafted hydroxyapatite) group and PLLA group. PLLA/PLLA-gHA and PLLA plates were embedded in the muscular bags of the erector spinae and also implanted to fix mandibular bone fractures in respective groups. At 1, 2, 3, 6, 9, and 12 months postoperatively, the PLLA/PLLA-gHA and PLLA plates were evaluated by adsorption and degradation tests, and the mandibles were examined through radiographic analysis, biomechanical testing, and histological analysis. The PLLA/PLLA-gHA plates were non-transparent and showed a creamy white color, and the PLLA plates were transparent and faint yellow in color. At all time points following surgery, adsorption and degradation of the PLLA/PLLA-gHA plates were significantly less than those of the PLLA plates, and the lateral and longitudinal bending strengths of the surgically treated mandibles of the beagle dogs in the PLLA/PLLA-gHA group were significantly greater than those of the PLLA group and reached almost the value of intact mandibles at 12 months postoperatively. Additionally, relatively rapid bone healing was observed in the PLLA/PLLA-gHA group with the formation of new lamellar bone tissues at 12 months after the surgery. The PLLA/PLLA-gHA nano-composite can be employed as a biodegradable material for internal fixation of mandibular bone fractures. PMID:26551378

  5. The effect of bone marrow aspirate, bone graft and collagen composites on fixation of bone implants

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2007-01-01

     Introduction: Replacement of extensive local bone loss especially in revision joint arthroplasties is a significant clinical challenge. Autogenous and allogenic cancellous bone grafts have been the gold standard in reconstructive orthopaedic surgery, but it is well known that there is morbidity...... associated with harvesting of autogenous bone graft and limitations in the quantity of bone available. Disadvantages of allograft include the risk of bacterial or viral contamination and non union as well as the potential risk of disease transmission. Alternative options are attractive and continue to be...... sought. Hydroxyapatite and collagen composites have the potential in mimicking and replacing skeletal bones. Aim: This study attempted to determine the effect of hydroxyapatite/collagen composites in the fixation of bone implants. The composites used in this study is produced by Institute of Science and...

  6. Fixation of a human rib by an intramedullary telescoping splint anchored by bone cement.

    Science.gov (United States)

    Liovic, Petar; Šutalo, Ilija D; Marasco, Silvana F

    2016-09-01

    A novel concept for rib fixation is presented that involves the use of a bioresorbable polymer intramedullary telescoping splint. Bone cement is used to anchor each end of the splint inside the medullary canal on each side of the fracture site. In this manner, rib fixation is achieved without fixation device protrusion from the rib, making the splint completely intramedullary. Finite element analysis is used to demonstrate that such a splint/cement composite can preserve rib fixation subjected to cough-intensity force loadings. Computational fluid dynamics and porcine rib experiments were used to study the anchor formation process required to complete the fixation. PMID:26733094

  7. Fixation strength analysis of cup to bone material using finite element simulation

    Science.gov (United States)

    Anwar, Iwan Budiwan; Saputra, Eko; Ismail, Rifky; Jamari, J.; van der Heide, Emile

    2016-04-01

    Fixation of acetabular cup to bone material is an important initial stability for artificial hip joint. In general, the fixation in cement less-type acetabular cup uses press-fit and screw methods. These methods can be applied alone or together. Based on literature survey, the additional screw inside of cup is effective; however, it has little effect in whole fixation. Therefore, an acetabular cup with good fixation, easy manufacture and easy installation is required. This paper is aiming at evaluating and proposing a new cup fixation design. To prove the strength of the present cup fixation design, the finite element simulation of three dimensional cup with new fixation design was performed. The present cup design was examined with twist axial and radial rotation. Results showed that the proposed cup design was better than the general version.

  8. The influence of tibial component fixation techniques on resorption of supporting bone stock after total knee replacement

    NARCIS (Netherlands)

    Chong, D.Y.; Hansen, U.N.; Venne, R. van der; Verdonschot, N.J.J.; Amis, A.A.

    2011-01-01

    Periprosthetic bone resorption after tibial prosthesis implantation remains a concern for long-term fixation performance. The fixation techniques may inherently aggravate the "stress-shielding" effect of the implant, leading to weakened bone foundation. In this study, two cemented tibial fixation ca

  9. Development of a biodegradable bone cement for craniofacial applications.

    Science.gov (United States)

    Henslee, Allan M; Gwak, Dong-Ho; Mikos, Antonios G; Kasper, F Kurtis

    2012-09-01

    This study investigated the formulation of a two-component biodegradable bone cement comprising the unsaturated linear polyester macromer poly(propylene fumarate) (PPF) and crosslinked PPF microparticles for use in craniofacial bone repair applications. A full factorial design was employed to evaluate the effects of formulation parameters such as particle weight percentage, particle size, and accelerator concentration on the setting and mechanical properties of crosslinked composites. It was found that the addition of crosslinked microparticles to PPF macromer significantly reduced the temperature rise upon crosslinking from 100.3°C ± 21.6°C to 102.7°C ± 49.3°C for formulations without microparticles to 28.0°C ± 2.0°C to 65.3°C ± 17.5°C for formulations with microparticles. The main effects of increasing the particle weight percentage from 25 to 50% were to significantly increase the compressive modulus by 37.7 ± 16.3 MPa, increase the compressive strength by 2.2 ± 0.5 MPa, decrease the maximum temperature by 9.5°C ± 3.7°C, and increase the setting time by 0.7 ± 0.3 min. Additionally, the main effects of increasing the particle size range from 0-150 μm to 150-300 μm were to significantly increase the compressive modulus by 31.2 ± 16.3 MPa and the compressive strength by 1.3 ± 0.5 MPa. However, the particle size range did not have a significant effect on the maximum temperature and setting time. Overall, the composites tested in this study were found to have properties suitable for further consideration in craniofacial bone repair applications. PMID:22499285

  10. Study of Bone-screw Surface Fixation in Lumbar Dynamic Stabilization

    Institute of Scientific and Technical Information of China (English)

    Yun-Gang Luo; Tao Yu; Guo-Min Liu; Nan Yang

    2015-01-01

    Background:We aimed to use the animal model of dynamic fixation to examine the interaction of the pedicle screw surface with surrounding bone,and determine whether pedicle screws achieve good mechanical stability in the vertebrae.Methods:Twenty-four goats aged 2-3 years had Cosmic(R) pedicle screws implanted into both sides of the L2-L5 pedicles.Twelve goats in the bilateral dynamic fixation group had fixation rods implanted in L2-L3 and L4-L5.Twelve goats in the unilateral dynamic fixation group had fixation rods randomly fixed on one side of the lumbar spine.The side that was not implanted with fixation rods was used as a static control group.Results:In the static control group,new bone was formed around the pedicle screw and on the screw surface.In the unilateral and bilateral dynamic fixation groups,large amounts of connective tissue formed between and around the screw threads,with no new bone formation on the screw surface; the pedicle screws were loose after the fixed rods were removed.The bone mineral density and morphological parameters of the region of interest (ROI) in the unilateral and bilateral dynamic fixation group were not significantly different (P > 0.05),but were lower in the fixed groups than the static control group (P < 0.05).This showed the description bone of the ROI in the static control group was greater than in the fixation groups.Under loading conditions,the pedicle screw maximum pull force was not significantly different between the bilateral and unilateral dynamic fixation groups (P > 0.05); however the maximum pull force of the fixation groups was significantly less than the static control group (P < 0.01).Conclusions:Fibrous connective tissue formed at the bone-screw interface under unilateral and bilateral pedicle dynamic fixation,and the pedicle screws lost mechanical stability in the vertebrae.

  11. Engineered polycaprolactone–magnesium hybrid biodegradable porous scaffold for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Hoi Man Wong

    2014-10-01

    Full Text Available In this paper, we describe the fabrication of a new biodegradable porous scaffold composed of polycaprolactone (PCL and magnesium (Mg micro-particles. The compressive modulus of PCL porous scaffold was increased to at least 150% by incorporating 29% Mg particles with the porosity of 74% using Micro-CT analysis. Surprisingly, the compressive modulus of this scaffold was further increased to at least 236% when the silane-coupled Mg particles were added. In terms of cell viability, the scaffold modified with Mg particles significantly convinced the attachment and growth of osteoblasts as compared with the pure PCL scaffold. In addition, the hybrid scaffold was able to attract the formation of apatite layer over its surface after 7 days of immersion in normal culture medium, whereas it was not observed on the pure PCL scaffold. This in vitro result indicated the enhanced bioactivity of the modified scaffold. Moreover, enhanced bone forming ability was also observed in the rat model after 3 months of implantation. Though bony in-growth was found in all the implanted scaffolds. High volume of new bone formation could be found in the Mg/PCL hybrid scaffolds when compared to the pure PCL scaffold. Both pure PCL and Mg/PCL hybrid scaffolds were degraded after 3 months. However, no tissue inflammation was observed. In conclusion, these promising results suggested that the incorporation of Mg micro-particles into PCL porous scaffold could significantly enhance its mechanical and biological properties. This modified porous bio-scaffold may potentially apply in the surgical management of large bone defect fixation.

  12. Design and fabrication of biomimetic multiphased scaffolds for ligament-to-bone fixation.

    Science.gov (United States)

    He, Jiankang; Zhang, Wenyou; Liu, Yaxiong; Li, Xiang; Li, Dichen; Jin, Zhongmin

    2015-05-01

    Conventional ligament grafts with single material composition cannot effectively integrate with the host bones due to mismatched properties and eventually affect their long-term function in vivo. Here we presented a multi-material strategy to design and fabricate composite scaffolds including ligament, interface and bone multiphased regions. The interface region consists of triphasic layers with varying material composition and porous structure to mimic native ligament-to-bone interface while the bone region contains polycaprolactone (PCL) anchor and microchanneled ceramic scaffolds to potentially provide combined mechanical and biological implant-bone fixation. Finite element analysis (FEA) demonstrated that the multiphased scaffolds with interference value smaller than 0.5 mm could avoid the fracture of ceramic scaffold during the implantation process, which was validated by in-vitro implanting the multiphased scaffolds into porcine joint bones. Pull-out experiment showed that the initial fixation between the multiphased scaffolds with 0.47 mm interference and the host bones could withstand the maximum force of 360.31±97.51 N, which can be improved by reinforcing the ceramic scaffolds with biopolymers. It is envisioned that the multiphased scaffold could potentially induce the regeneration of a new bone as well as interfacial tissue with the gradual degradation of the scaffold and subsequently realize long-term biological fixation of the implant with the host bone. PMID:25746239

  13. Degradation and biological properties of Ca-P contained micro-arc oxidation self-sealing coating on pure magnesium for bone fixation

    OpenAIRE

    Wang, Weidan; Wan, Peng; Liu, Chen; Tan, Lili; Li, Weirong; Li, Lugee; Yang, Ke

    2014-01-01

    Poor corrosion resistance is one of the main disadvantages for biodegradable magnesium-based metals, especially applied for bone fixation, where there is a high demand of bio-mechanical strength and stability. Surface coating has been proved as an effective method to control the in vivo degradation. In this study a Ca-P self-sealing micro-arc oxidation (MAO) coating was studied to verify its efficacy and biological properties by in vitro and in vivo tests. It was found that the MAO coating co...

  14. Radiostrontium clearance and bone formation in response to simulated internal screw fixation

    International Nuclear Information System (INIS)

    Changes in radiostrontium clearance (SrC) and bone formation (tetracycline labeling) were observed in the femurs of skeletally mature dogs following the various operative steps involved in bone screw fixation. Drilling, but not periosteal stripping, produced a small but statistically significant increase in SrC and endosteal bone formation in the distal third of the bone. Strontium clearance values equivalent to those produced by drilling alone were recorded after screw fixation at low or high torque (5 versus 20 inch pounds), as well as by the insertion of loosely fitting stainless steel implants. Bone formation (equals the percentage tetracycline-labeled trabecular bone surfaces) was increased by 30% when SrC values exceeded 3.5 ml/100 g bone/min, and the relationship was linear when SrC values ranged between 1.0 and 7.0 ml/100 g bone/min. The changes in SrC and bone formation one-week after bone screw application are primarily those associated with a response to local trauma caused by drilling

  15. Coupled external fixator and skin flap transposition for treatment of exposed and nonunion bone

    Directory of Open Access Journals (Sweden)

    ZHAO Yong-gang

    2011-02-01

    Full Text Available 【Abstract】Objective: To discuss the effect of coupled external fixator and skin flap transposition on exposed and nonunion bones. Methods: The data of 12 cases of infected nonunion and exposed bone following open fracture treated in our hospital during the period of March 1998 to June 2008 were analysed. There were 10 male patients, 2 female patients, whose age were between 19-52 years and averaged 28 years. There were 10 tibial fractures and 2 femoral fractures. The course of diseases lasted for 12-39 months with the mean period of 19 months. All the cases were treated by the coupled external fixator and skin flap transposition. Results: Primary healing were achieved in 10 cases and delayed healing in 2 cases in whom the tibia was exposed due to soft tissue defect and hence local flap transposition was performed. All the 12 cases had bony union within 6-12 months after operation with the average time of 8 months. They were followed up for 1-3 years and all fractures healed up with good function and no infection recurrence. Conclusion: The coupled external fixator and skin flap transposition therapy have shown optimal effects on treating infected, exposed and nonunion bones. Key words: External fixators; Fracture fixation; Infection; Surgical flap

  16. The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan

      The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants IN SHEEP   Ph.D. Student, Hassan Babiker; Associate Professor, Ph.D. Ming Ding; Professor, dr.med., Soren Overgaard. Department of Orthopaedic Surgery, Odense University Hospital......, Odense, Denmark   Background: Hydroxyapatite and collagen composites (HA/coll) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effect of newly developed HA/coll-composites with and without bone marrow aspirate (BMA) in order to enhance the fixation of...... bone implants.   Materials and Methods: Titanium alloy implants were inserted into bilateral femoral condyles of 8 skeletally mature sheep, four in each sheep. The implant has a circumferential gap of 2 mm. The gap was filled with: HA/coll; HA/coll-BMA; autograft or allograft. Allograft was served as...

  17. FIBULA AND ILIAC BONE GRAFTING WITH INTERNAL FIXATION FOR GAINT CELL TUMOUR OF PROXIMAL TIBIA

    OpenAIRE

    Nishant Gaonkar; Takale; Kolekar; Vaibhav Koli; Jimit Shah

    2015-01-01

    Middle aged old female with swelling in left knee suggestive of giant cell tumour was treated with excisional biopsy with curettage, phenol cauterisation , bone graft and proximal tibia locking plate fixation. Sample sent for histopathology was consistent with diagnosis of giant cell tumour. No recurrence has been seen after 1 year of follow up.

  18. FIBULA AND ILIAC BONE GRAFTING WITH INTERNAL FIXATION FOR GAINT CELL TUMOUR OF PROXIMAL TIBIA

    Directory of Open Access Journals (Sweden)

    Nishant Gaonkar

    2015-02-01

    Full Text Available Middle aged old female with swelling in left knee suggestive of giant cell tumour was treated with excisional biopsy with curettage, phenol cauterisation , bone graft and proximal tibia locking plate fixation. Sample sent for histopathology was consistent with diagnosis of giant cell tumour. No recurrence has been seen after 1 year of follow up.

  19. Management of periarticular fractures of long bones of the lower extremity by hybrid external fixation

    Directory of Open Access Journals (Sweden)

    Natarajan Mayil

    2006-01-01

    Full Text Available Background : Management of periarticular fractures is associated with many complications. Hybrid fixators allows for early partial weight bearing and range of motion exercises at adjoining joints. Furthermore, it promotes callous formation by continuous axial micro movements in the fixation frame. Methods : We have prospectively analyzed the results of hybrid external fixation in the management of periarticular fractures of long bones of the lower extremity in 20 patients accounting for 22 limbs. We treated 19 fractures (18 compound and 1 closed and three fracture nonunions with this method. The mean age of the patients was 36.5 years. In 12 patients hybrid fixation was the primary procedure while in 8 patients hybrid fixation was done following initial emergency AO Uniplanar external fixation. Fourteen patients required subsequent surgeries such as bone grafting and soft tissue cover. Results : The mean follow up of our patients was 13.2 months (5 - 25 months. We achieved excellent results in 10 fractures, good in 4 fractures, fair in 3 fractures and poor results in 3 fractures. Two patients were lost to follow up. Bony union was achieved in 18 of the fractures. A short-term acceptable result was achieved in 17 cases. Conclusion : Hybrid external fixation is a very effective and useful treatment modality in the management of fractures close to a joint providing excellent to good results. It combines the advantages of both Ilizarov and AO external fixators. It is minimally invasive, modular and yet efficient in promoting massive new proliferative callus formation at the fracture site.

  20. Biodegradation rate of shellac coated bovine hydroxyapatite for bone filler material

    Science.gov (United States)

    Triyono, Joko; Triyono, Susilowati, Endang; Murdiyantara, Suci Anindya

    2016-03-01

    This work reports on the effect of shellac coated hydroxyapatite (HA) on the biodegradation rate. The HA was processed from bovine bone. Shellac was derived from the resinous secretion of the lac insect. The aims of the addition of shellac solution is to know how the biodegradation rate material in the Phosphate Buffered Saline (PBS) solution. The four different of shellac solutions (2,5%; 5%; 7,5%; and 10% weight) coated HA scaffoldand one ratio as a control. It was concluded that the ability of biodegradation rate a materialwas not influenced by the ratio of shellac. All materials were biodegradedwhen they were soaked in PBS solution.

  1. New method of fixation of in-bone implanted prosthesis

    Directory of Open Access Journals (Sweden)

    Mark Pitkin, PhD

    2013-08-01

    Full Text Available This article presents results on the effectiveness of a new version of the titanium porous composite skin and bone integrated pylon (SBIP. The SBIP is designed for direct skeletal attachment of limb prostheses and was evaluated in a preclinical study with three rabbits. In accordance with the study protocol, a new version of the pylon (SBIP-3 was implanted into the hind leg residuum of three rabbits. The SBIP-3 has side fins that are designed to improve the bond between the bone and pylon. The fins are positioned inside two slots precut in the bone walls; their length can be adjusted to match the thickness of the bone walls. After 13 (animal 1 or 26 (animals 2 and 3 wk, the animals were sacrificed and samples collected for histopathological analysis. The space between the fins and the bone into which they were fit was filled with fibrovascular tissue and woven bone. No substantial inflammation was found. We suggest that if further studies substantiate the present results, the proposed method can become an alternative to the established technique of implanting prostheses into the medullary canal of the hosting bone.

  2. BIOMECHANICAL STUDY OF TRANSCORTICAL OR TRANSTRABECULAR BONE FIXATION OF PATELLAR TENDON GRAFT WITH BIOABSORBABLE PINS IN ACL RECONSTRUCTION IN SHEEP

    Science.gov (United States)

    Albano, Mauro Batista; Borges, Paulo César; Namba, Mario Massatomo; da Silva, João Luiz Vieira; de Assis Pereira Filho, Francisco; Filho, Edmar Stieven; Matias, Jorge Eduardo Fouto

    2015-01-01

    Objective: To determine the initial resistance of fixation using the Rigid Fix® system, and compare it with traditional fixation methods using metal interference screws; and to evaluate the resistance of the fixation with the rigid fix system when the rotational position of the bone block is altered in the interior of the femoral tunnel. Methods: forty ovine knee specimens (stifle joints) were submitted to anterior cruciate ligament reconstruction (ACL) using a bone-tendon-bone graft. In twenty specimens, the Rigid Fix method was used; this group was subdivided into two groups: ten knees the pins transfixed only the spongious area of the bone block, and ten for fixation passing through the layer of cortical bone. In the twenty remaining specimens, the graft was fixed with 9mm metal interference screws. Results: comparison of the RIGIDFIX® method with the metal interference screw fixation method did not show any statistically significant differences in terms of maximum load and rigidity; also, there were no statistically significant differences when the rotational position of the bone block was altered inside the femoral tunnel. For these evaluations, a level of significance of p < 0.017 was considered. Conclusion: fixation of the bone-tendon-bone graft with 2 bioabsorbable pines, regardless of the rotational position inside the femoral tunnel, gave a comparable fixation in terms of initial resistance to the metal interference screw, in this experimental model. PMID:27027081

  3. The short-term fixation of radiopharmaceuticals in bone

    International Nuclear Information System (INIS)

    The relationship between local blood flow and bone clearance of 18 F, 32 P-P (orthophosphate), 32 P-PPi (pyrophosphate), 45 Ca, 85 Sr, 99mTc- and 113 Sn-EHDP was evaluated in the non-adult rat. During one single blood passage nearly 100% of 18 F was extracted in the femoral diaphysis, the extraction efficiency for the other radiopharmaceuticals was about 40%. Blood flow and bone clearance was higher and the extraction efficiency lower in the distal femoral epiphysis including the growth plate. The short-term bone uptake of 32 P-P was lowered considerably by the simultaneous application of inactive orthophosphate, whereas the bone uptake of 32 P-PP, was not suppressed. It is suggested that the rapid deposition of radiopharmaceuticals in bone is not caused by an ionic exchange process on crystal surfaces of already existing mineral but is due to an ionic exchange during the precipitation of calcium phosphate in the calcifying bone matrix. Only 18 F is exchanged with hydroxyl groups of already precipitated hydroxyapatite, whereas the calcium and phosphate ions in the precipitated hydroxyapatite are not further accessible to an exchange process. (orig.) 891 MG/orig. 892 MBE

  4. Augmentation of femoral neck fracture fixation with an injectable calcium-phosphate bone mineral cement.

    Science.gov (United States)

    Stankewich, C J; Swiontkowski, M F; Tencer, A F; Yetkinler, D N; Poser, R D

    1996-09-01

    The first goal of this study was to determine if augmentation with an injectable, in situ setting, calcium-phosphate cement that is capable of being remodeled and was designed to mimic bone mineral significantly improved the strength and stiffness of fixation in a cadaveric femoral neck fracture model. The second goal was to determine if greater increases in fixation strength were achieved as the bone density of the specimen decreased. Sixteen pairs of fresh cadaveric human femora with a mean age of 70.9 years (SD = 17.2 years) were utilized. The bone density of the femoral neck was measured with dual-energy x-ray absorptiometry. The femoral head was impacted vertically with the femoral shaft fixed in 12 degrees of adduction using a materials testing machine to create a fully displaced fracture. Following fracture, 30% inferior comminution was created in each specimen. One randomly chosen femur from each pair underwent anatomic reduction and fixation with three cannulated cancellous bone screws, 7 mm in diameter, in an inverted triangle configuration. The contralateral femur underwent the same fixation augmented with calcium-phosphate cement. Specimens were preconditioned followed by 1.000 cycles to one body weight (611.6 N) at 0.5 Hz to simulate single-limb stance loading. The stiffness in the first cycle was observed to be significantly greater in cement-augmented specimens compared with unaugmented controls (p bone mineral cement failed at a mean of 4,573 N (SD = 1,243 N); this was significantly greater (p bone density (p = 0.25, R2 = 0.09), was weakly correlated to the volume of cement injected (p = 0.07, R2 = 0.22), and was inversely related to the fixation failure load of the control specimen (p = 0.001, R2 = 0.54). There was a mean relative improvement in fixation strength of 169.6% (SD = 77.5). These findings suggest that calcium-phosphate cement provides initial beneficial augmentation to fixation of femoral neck fractures. PMID:8893773

  5. Non-vascularized bone graft with herbert-type screw fixation for proximal pole scaphoid nonunion

    International Nuclear Information System (INIS)

    Since proximal pole fractures of the scaphoid are frequently overlooked, the poor vascularity in the proximal pole fragment often leads to nonunion. Vascularized bone grafts have been recently tested in cases with scaphoid proximal pole nonunion, but the indication for this treatment has not been well established. Alternatively, we have been treating such patients with a non-vascularized iliac bone graft and Herbert-type screw fixation with considerable success. The purpose of this investigation is to evaluate these cases retrospectively and clarify the surgical efficacy of our procedure. Between 1996 and 2009, 11 consecutive patients with proximal pole scaphoid nonunion were treated with a non-vascularized corticocancellous iliac bone graft and Herbert-type screw fixation. They were all male aged from 12 to 26 years. In two patients, avascular changes were recognized in the proximal pole in preoperative radiographs or MRI. Follow-up ranged from 12 to 76 months. Bone union was radiographically confirmed in all patients, who returned to their former activities without any complications. The period from operation to union ranged from 12 to 24 weeks. The mean Mayo modified wrist score was 76.4 points preoperatively and 91.4 points postoperatively, and was improved in all cases. A non-vascularized iliac bone graft with Herbert-type screw fixation obtained satisfactory clinical and radiographic results in cases with scaphoid proximal pole nonunion, regardless of the vascularity in the proximal fragment. (author)

  6. Serial strain gauge measurement of bone healing in hoffmann® external fixation.

    Science.gov (United States)

    Nishimura, N

    1984-04-01

    In order to better assess callus strength for postoperative management of Hoffmann external fixation patients, the author attempted to estimate the amount of strain when bending or compressing the fracture site with a strain gauge glued to the middle of a connecting rod. Calculations in a computer architectural model of a plane beam structure show that the amount of strain on a connecting rod would decrease hyperbolically when the mechanical properties of the callus increased. Strength testing in a cadaveric crural bone confirms the importance of callus volume. The serial strain gauge measurement technique was applied to a series of 23 cases treated with Hoffmann external fixation, 20 of which achieved bone healing. On the basis of the bone healing curve obtained with the strain gauge measurements, the healing process is classified into five types. PMID:24822815

  7. Bone compaction enhances fixation of weight-bearing hydroxyapatite-coated implants

    DEFF Research Database (Denmark)

    Kold, Søren; Rahbek, Ole; Vestermark, Marianne; Overgaard, Søren; Søballe, Kjeld

    2006-01-01

    The effect of bone compaction vs conventional drilling on the fixation of hydroxyapatite-coated implants was examined in a weight-bearing canine model. In each dog, one knee joint had the implant cavity prepared with drilling, the other with compaction. Eight dogs were euthanized after 2 weeks and...... implant fixation after 4 weeks. The results of this study suggest that compaction may be beneficial in optimizing the crucial initial implant stability, even when hydroxyapatite-coated implants with osteoconductive properties are inserted in vivo....

  8. Demineralized bone matrix and human cancellous bone enhance fixation of porous-coated titanium implants in sheep.

    Science.gov (United States)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2016-03-01

    Allogenic bone graft has been considered the gold standard in connection with bone graft material in revision joint arthroplasty. However, the lack of osteogenic potential and the risk of disease transmission are clinical challenges. The use of osteoinductive materials, such as demineralized bone matrix (DBM), alone or in combination with allograft or commercially available human cancellous bone (CB), may replace allografts, as they have the capability of inducing new bone and improving implant fixation through enhancing bone ongrowth. The purpose of this study was to investigate the effect of DBM alone, DBM with CB, or allograft on the fixation of porous-coated titanium implants. DBM100 and CB produced from human tissue were included. Both materials are commercially available. DBM granules are placed in pure DBM and do not contain any other carrier. Titanium alloy implants, 10 mm long × 10 mm diameter, were inserted bilaterally into the femoral condyles of eight skeletally mature sheep. Thus, four implants with a concentric gap of 2 mm were implanted in each sheep. The gap was filled with: (a) DBM; (b) DBM:CB at a ratio of 1:3; (c) DBM:allograft at a ratio of 1:3; or (d) allograft (gold standard), respectively. A standardized surgical procedure was used. At sacrifice 6 weeks after implantation, both distal femurs were harvested. The implant fixation was evaluated by mechanical push-out testing to test shear mechanical properties between implant and the host bone and by histomorphometry. Non-parametric tests were applied; p strengths among the DBM/CB, DBM/allograft and allograft groups were not statistically different. The strength of the DBM group was 0.01 MPa, which was statistical significantly lower than the other three groups (p < 0.05). Histomorphometry results showed that the bone ongrowth in the DBM group was statistically significantly lower than the other three groups, while the volume fraction of new bone showed no significant difference among

  9. Evaluation of K-wire fixation for nasal bone fractures using CT images

    International Nuclear Information System (INIS)

    A nasal bone fracture is the most common facial fracture. Successful treatment requires accurate diagnosis and careful surgical management. Fractures usually are diagnosed on the basis of macroscopic inspection and X-rays. In some cases, CT can be useful in diagnosis of nasal bone fractures because CT images have few shadows and consequently are of high contrast. The authors therefore utilized CT in the classification of 83 cases of nasal bone fractures. CT also was used in 36 cases for postoperative evaluation. During the five-year period from 1989 to 1994, the authors diagnosed 83 cases of nasal bone fractures. CT findings were used to evaluate the types of fractures, which were classified as lateral (unilateral and bilateral), frontal, and lateral-frontal mixed. Included were 22 cases of unilateral fracture, 26 cases of bilateral fracture, 25 cases of frontal fracture, and 8 cases of frontal-lateral fracture. The authors performed closed reduction utilizing K-wire fixation under general anesthesia. Reduction resulted in an angle of θ formed between the nasal bone and maxillary bone, and with its apex at the fracture point. Of the 36 cases postoperatively evaluated by CT, 11 showed excellent results, 12 good results, and 13 fair results. Eleven of the 13 fair reduction cases had a free bone at the fracture point. Five of the 6 cases of fair reduction lateral-frontal mixed fractures had a free bone at the fracture point. Based on CT findings, the authors concluded that reduction and fixation utilizing K-wire was insufficient in cases with free bone fragments. It therefore is important that the existence and position of any free bone fragment should be given careful consideration before undertaking surgery. (author)

  10. Histomorphometric evaluation of bone healing in rabbit fibular osteotomy model without fixation

    Directory of Open Access Journals (Sweden)

    Paixão Fabio B

    2008-01-01

    Full Text Available Abstract Background Animal models of fracture consolidation are fundamental for the understanding of the biological process of bone repair in humans, but histological studies are rare and provide only qualitative results. The objective of this article is to present the histomorphometric study of the bone healing process using an experimental model of osteotomy in rabbit fibula without interference of synthesis material. Methods Fifteen rabbits were submitted to fibular osteotomy without any fixation device. Groups of five animals were submitted to pharmacological euthanasia during a period of one (group A, two (group B and four weeks (group C after osteotomy. Histomorphometric evaluation was performed in the histological sections. Results During week one there was intense cellularity (67/field, a large amount of woven bone (75.7% and a small amount of lamellar bone (7.65%. At two weeks there was a decrease in woven bone (41.59% and an increase in lamellar bone (15.16%. At four weeks there was a decrease of cellularity (19.17/field and lamellar bone (55.56% exceeded the quantity of woven bone (31.68%. Conclusion Histomorphometric (quantitative evaluation of the present study was shown to be compatible with bone healing achieved in qualitative experimental models that have been commended in the literature.

  11. Simulated bone remodeling around two types of osseointegrated implants for direct fixation of upper-leg prostheses

    NARCIS (Netherlands)

    Tomaszewski, P.K.; Verdonschot, N.; Bulstra, S.K.; Rietman, J.S.; Verkerke, G.J.

    2012-01-01

    Direct attachment of an upper leg prosthesis to the skeletal system by a percutaneous implant is an alternative solution to the traditional socket fixation. In this study, we investigated long-term periprosthetic bone changes around two types of fixation implants using two different initial conditio

  12. [Serial strain gauge measurement of bone healing in Hoffmann external fixation].

    Science.gov (United States)

    Nishimura, N

    1984-01-01

    Since 1978, the author has applied Hoffmann external fixation to the treatment of open fractures and infected pseudoarthrosis of long bones in the lower limbs, but has some difficulties in determining when weight bearing should be started after operation, how much weight bearing should be and when the pin should be removed. As new method to mechanically analyze the callus strength, I tried to estimate the amount of strain at intervals of 2 to 3 weeks, beginning from the second week after operation, by bending or compressing the fracture site through the strain gauge glued to the middle of the external fixator's connecting rod. From a strength test by means of a model of fracture using a vinyl chloride pipe and also from a study of computer calculation using the model of plane beam structure for architectural design, it was found that the amount of the strain on the connecting rod decreased hyperbolically when the mechanical properties of the callus increased, and that it became constant when the mechanical properties of the callus reached 50% of the intact bone. The strength test using an cadaveric skin bone demonstrated that the callus volume was one of the most important and affecting factor. Twenty-three cases were treated by Hoffmann external fixation, and the bone healing was achieved in 20 of them. On the basis of the bone healing curve obtained by the serial strain gauge measurement in those cases, the bone healing process could be classified into 5 types: normal healing, slow healing, non-union, arrest in evolution and breakage of callus; and were employed as indexes in the post-operative rehabilitation program. PMID:6747402

  13. Internal fixation and bone grafting for intraarticular nonunion of tibial plateau: a report of four cases

    Institute of Scientific and Technical Information of China (English)

    Ramesh K Sen; Ashwani Soni; Uttam Chand Saini; Daljit Singh

    2011-01-01

    Intraarticular nonunion of tibial plateau is rare.In the literature,only 9 patients were found to be treated for intraarticular tibial plateau nonunion and they got varying results.Internal fixation along with bone grafting was done as a standard treatment in all cases.We treated 4 different profile cases of intraarticular tibial plateau nonunion in our institution by 4 different methods.We treated these cases with plaster of paris cast,internal fixation along with bone graft,arthrodesis with K-nail and total knee replacement.Case 1 was treated with plaster of paris (POP)cast as the patient refused surgery.The fracture was united and the patient was fully satisfied with full range of motion despite valgus malalignment.Case 2 was managed with open reduction internal fixation along with bone grafting.The patient had a good union and got full range of motion at the knee joint.Case 3 was treated with total knee arthroplasty due to her old age and got satisfactory result.Case 4 was an infected nonunion.Arthrodesis was done and the patient could walk with full weight bearing independently.We conclude that internal fixation along with bone grafting may not be suitable in all cases of intraarticular nonunion of tibial plateau.Causes of nonunion,present condition and range of motion of the knee joint,as well as the age of patient should be all considered and the treatment should be individualised according to each patient's situation.

  14. Coupled external fixator and skin flap transposition for treatment of exposed and nonunion bone

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong-gang; DING Jing; WANG Neng

    2011-01-01

    Objective: To discuss the effect of coupled external fixator and skin flap transposition on exposed and nonunion bones.Methods: The data of 12 cases of infected nonunion and exposed bone following open fracture treated in our hospital during the period of March 1998 to June 2008 were analysed. There were 10 male patients, 2 female patients,whose age were between 19-52 years and averaged 28 years.There were 10 tibial fractures and 2 femoral fractures. The course of diseases lasted for 12-39 months with the mean period of 19 months. All the cases were treated by the coupled external fixator and skin flap transposition.Results: Primary healing were achieved in 10 cases and delayed healing in 2 cases in whom the tibia was exposed due to soft tissue defect and hence local flap transposition was performed. All the 12 cases had bony union within 6-12 months afer operation with the average time of 8 months. They were followed up for 1-3 years and all fractures healed up with good function and no infection recurrence.Conclusion: The coupled external fixator and skin flap transposition therapy have shown optimal effects on treating infected, exposed and nonunion bones.

  15. The effects of laparoscopic mesh fixation device on bone, costo-chondral junction and tendon site.

    Science.gov (United States)

    Ekçi, Baki; Altinli, Ediz; Dervisoglu, Sergülen; Demir, Mustafa; Tasci, Ihsan

    2011-01-01

    Osteitis pubis is one of the important complications of inguinal hernia repair surgery occurring with the placement of sutures through the periosteum. The aim of this study is to evaluate scintigraphic and histopathological alterations associated with the use of mesh fixation device on pelvic bone, cartilage and tendons in an experimental animal model. Twenty New-Zealand young male rabbits were used. A mesh fixation device was inserted at each animal's costa-chondral junction, superior anterior iliac crest, and achiles tendon. One week prior to the surgery and 16 weeks after the operation, scintigraphic evaluation was performed. Histopathological evaluation was performed at the end of study. No nuclear activity or pathological change was found at bone site (p > 0.05). Foreign body reaction was evident at the tendon and costa-chondral site (p = 0.001). In conclusion; the mesh fixation device leads to foreign body reaction in costa-chondral junction and tendon. It does not cause any nuclear activity increase. PMID:21657163

  16. Internal fixation and muscle pedicle bone grafting in femoral neck fractures

    Directory of Open Access Journals (Sweden)

    Gupta A

    2008-01-01

    Full Text Available Background: The treatment of displaced intracapsular femoral neck fracture is still an unsolved problem. Non-union and avascular necrosis are the two main complications of this fracture, especially if patient presents late. Muscle pedicle bone grafting has been advocated to provide additional blood supply. We present analysis of our 32 cases of displaced femoral neck fracture treated by internal fixation and quadratus femoris based muscle pedicle bone grafting. Materials and Methods: Open reduction and internal fixation with muscle pedicle grafting was done in 32 patients. The age of patients varied from 14-62 years (average age 45 years with male to female ratio of 13:3. Twenty-nine fractures were more than three weeks old. All the cases were treated by Meyers′ procedure. The fracture was internally fixed after open reduction and then a muscle pedicle graft was applied. It was supplemented by cancellous bone graft in seven cases. Fixation was done by parallel cancellous lag screws ( n = 19, crossed Garden′s screws ( n = 7, parallel Asnis screws ( n = 5 and Moore′s pin ( n = 1.Quadratus femoris muscle pedicle graft was used in 32 cases. In the initial 12 cases the graft was fixed with circumferential proline sutures, but later, to provide a secure fixation, the graft was fixed with a cancellous screw ( n = 20. Postoperative full weight bearing was deferred to an average of 10 weeks. Results: Union was achieved in 26/29 (89.65% cases which could be followed for an average period of 3.4 years, (2-8.5 years with good functional results and had the ability to squat and sit cross-legged. Results were based on hip rating system given by Salvatti and Wilson. The results were excellent in 15 cases, good in four cases, fair in four cases and poor in six cases. Complications were avascular necrosis ( n = 2, transient foot drop ( n = 2, coxa-vara ( n = 1 and temporary loss of scrotal sensation ( n = 1. Conclusion: Muscle pedicle bone grafting with

  17. Nanocomposites of Polyacrylic Acid Nanogels and Biodegradable Polyhydroxybutyrate for Bone Regeneration and Drug Delivery

    Directory of Open Access Journals (Sweden)

    Mikael Larsson

    2014-01-01

    Full Text Available Biodegradable cell scaffolds and local drug delivery to stimulate cell response are currently receiving much scientific attention. Here we present a nanocomposite that combines biodegradation with controlled release of lithium, which is known to enhance bone growth. Nanogels of lithium neutralized polyacrylic acid were synthesized by microemulsion-templated polymerization and were incorporated into a biodegradable polyhydroxybutyrate (PHB matrix. Nanogel size was characterized using dynamic light scattering, and the nanocomposites were characterized with regard to structure using scanning electron microscopy, mechanical properties using tensile testing, permeability using tritiated water, and lithium release in PBS using a lithium specific electrode. The nanogels were well dispersed in the composites and the mechanical properties were good, with a decrease in elastic modulus being compensated by increased tolerance to strain in the wet state. Approximately half of the lithium was released over about three hours, with the remaining fraction being trapped in the PHB for subsequent slow release during biodegradation. The prepared nanocomposites seem promising for use as dual functional scaffolds for bone regeneration. Here lithium ions were chosen as model drug, but the nanogels could potentially act as carriers for larger and more complex drugs, possibly while still carrying lithium.

  18. Efficacy of a small cell-binding peptide coated hydroxyapatite substitute on bone formation and implant fixation in sheep

    DEFF Research Database (Denmark)

    Ding, Ming; Andreasen, Christina Møller; Dencker, Mads L.;

    2015-01-01

    hydroxyapatite (ABM/P-15); hydroxyapatite + βtricalciumphosphate+ Poly-Lactic-Acid (HA/βTCP-PDLLA); or ABM/P-15+HA/βTCP-PDLLA. After nine weeks, bone-implant blocks were harvested and sectioned for micro-CT scanning, push-out test, and histomorphometry. Significant bone formation and implant fixation could...... implant were not significantly different among the four groups. The ABM/P-15 group had similar shear mechanical properties on implant fixation as the allograft group. Adding HA/βTCP-PDLLA to ABM/P-15 did not significantly change these parameters. This study revealed that ABM/P-15 had significantly bone...

  19. Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss

    NARCIS (Netherlands)

    Tomaszewski, P. M.; van Diest, M.; Bulstra, S. K.; Verdonschot, N.; Verkerke, G. J.

    2012-01-01

    Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system. Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining biomechanic

  20. Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss.

    NARCIS (Netherlands)

    Tomaszewski, P.K.; Diest, M. van; Bulstra, S.K.; Verdonschot, N.J.; Verkerke, G.J.

    2012-01-01

    Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system, Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining biomechanic

  1. Biocompatibility, resorption and biofunctionality of a new synthetic biodegradable membrane for guided bone regeneration.

    Science.gov (United States)

    Hoornaert, Alain; d'Arros, Cyril; Heymann, Marie-Francoise; Layrolle, Pierre

    2016-01-01

    Membranes for guided bone regeneration (GBR) were prepared from the synthetic biodegradable polymer poly-D,L-lactic/glycolic acid (PLGA). This GBR membrane has a bi-layered structure with a dense film to prevent gingival fibroblast ingrowth and ensure mechanical function, and a micro-fibrous layer to support colonization by osteogenic cells and promote bone regeneration. Hydrolysis and biodegradation were both studied in vitro through soaking in phosphate buffered saline (PBS) and in vivo by implantation in the subcutis of rats for 4, 8, 16, 26, 48 and 52 weeks. Histology revealed an excellent colonization of the micro-fibrous layer by cells with a minimal inflammatory reaction during resorption. GBR using the synthetic PLGA membrane was evaluated on critical-size calvaria defects in rats for 4 and 8 weeks. Radiographs, micro-computed tomography and histology showed bone regeneration with the PLGA membrane, while the defects covered with a collagen membrane showed a limited amount of mineralized bone, similar to that of the defect left empty. The biofunctionality of the PLGA membranes was also compared to collagen membranes in mandible defects in rabbits, associated or not with beta-tricalcium phosphate granules. This study revealed that the bi-layered synthetic membrane made of PLGA was safer, more biocompatible, and had a greater controlled resorption rate and bone regeneration capacity than collagen membranes. This new PLGA membrane could be used in pre-implantology and peri-odontology surgery. PMID:27509180

  2. Improving Distal Fixation with Total Shoulder Arthroplasty in Cases of Severe Humeral Bone Loss.

    Science.gov (United States)

    Jacobson, Amanda; Stroud, Nick; Roche, Christopher P

    2015-12-01

    The usage of and indications for total shoulder arthroplasty have grown in recent years. Certain aspects of these arthro - plasty procedures can be very complex, especially in revi - sion and fracture cases, often leading to proximal humerus bone loss. For cases with significant bone loss, there is a need for improved devices with additional options to treat a wider range of deformities while also mitigating existing complications and rates, such as poor distal fixation, inad - equate soft tissue reattachment options, and joint instability. To that end, a fatigue and torsional test was conducted on two different devices to assess the ability of each to survive an extreme fatigue and torsional load when assembled in worst-case configurations. Evaluation of the Equinoxe ® humeral reconstruction prosthesis demonstrated superior fixation in both the fatigue loading scenario and also the torsional loading scenario as compared to the 8 mm x 215 mm cemented humeral long stem, where each had only 80 mm of cemented fixation. The results of the fatigue test demonstrated that despite the humeral reconstruction pros - thesis being subjected to a 960 N force and 45 Nm bending moment (which was significantly more challenging than the 576 N force and 24.2 Nm bending moment subjected to the cemented humeral long stem), the humeral reconstruction prosthesis completed 1 M cycles without fracture or failure. Additionally, the Equinoxe ® humeral reconstruction pros - thesis was associated with a significantly greater torsional resistance in both the torque to initial slip (29.4 Nm versus 8.2 Nm; p = 0.0002) and also the maximum torque to failure (44.3 Nm versus 12.1 Nm; p fer the potential for the Equinoxe ® humeral reconstruction prosthesis to be an improved treatment option for patients with proximal humeral bone loss, though clinical follow-up is necessary to confirm these positive biomechanical results. PMID:26631195

  3. Acid-resistant calcium silicate-based composite implants with high-strength as load-bearing bone graft substitutes and fracture fixation devices.

    Science.gov (United States)

    Wei, Chung-Kai; Ding, Shinn-Jyh

    2016-09-01

    To achieve the excellent mechanical properties of biodegradable materials used for cortical bone graft substitutes and fracture fixation devices remains a challenge. To this end, the biomimetic calcium silicate/gelatin/chitosan oligosaccharide composite implants were developed, with an aim of achieving high strength, controlled degradation, and superior osteogenic activity. The work focused on the effect of gelatin on mechanical properties of the composites under four different kinds of mechanical stresses including compression, tensile, bending, and impact. The evaluation of in vitro degradability and fatigue at two simulated body fluid (SBF) of pH 7.4 and 5.0 was also performed, in which the pH 5.0 condition simulated clinical conditions caused by bacterial induced local metabolic acidosis or tissue inflammation. In addition, human mesenchymal stem cells (hMSCs) were sued to examine osteogenic activity. Experimental results showed that the appropriate amount of gelatin positively contributed to failure enhancement in compressive and impact modes. The 10wt% gelatin-containing composite exhibits the maximum value of the compressive strength (166.1MPa), which is within the reported compressive strength for cortical bone. The stability of the bone implants was apparently affected by the in vitro fatigue, but not by the initial pH environments (7.4 or 5.0). The gelatin not only greatly enhanced the degradation of the composite when soaked in the dynamic SBF solution, but effectively promoted attachment, proliferation, differentiation, and formation of mineralization of hMSCs. The 10wt%-gelatin composite with high initial strength may be a potential implant candidate for cortical bone repair and fracture fixation applications. PMID:27254281

  4. APPLICATION OF A BIODEGRADABLE MATERIAL FOR BONE REPLACEMENT IN TRAUMATOLOGY

    OpenAIRE

    T. V. Druzhinina; K. V. Trofimov; V. F. Naydanov; A. V. Rostovzev; D. V. Burkov; A. V. Zhulyabin; A. A. Isupov; A. V. Verevin

    2014-01-01

    20 men (medium age (31.5 ± 13.5) years) were studied. All patients underwent arthroscopic auditing plastic anterior cruciate ligament of the knee. Osteoregeneration dynamics were determined by biochemical testing of blood serum and X-ray computed tomography (CT) of the fracture in 1–4 months after surgery. As a result, an estimation of the bone tissue reparative regeneration according to CT data in 10 patients with a defect of the patella, treated with the material is provided. The obtained r...

  5. Outcome after open reduction and internal fixation of intraarticular fractures of the calcaneum without the use of bone grafts

    OpenAIRE

    Pendse Aniruddha; Daveshwar R; Bhatt Jay; Shivkumar

    2006-01-01

    Background: Intraarticular fractures of calcaneum are commenest type of calcaneal fractures. Lots of controversies exist about the ideal management for them. The focus is now shifting on operative management by open reduction and internal fixation for these fractures with or without the use of bone grafts. Method: Thirty intraarticular fractures classified by Essex Lopresti radiological classification, were treated by open reduction and fixation. The patients were followed over a mean peri...

  6. Bone cement enhanced pedicle screw fixation combined with vertebroplasty for elderly patients with malignant spinal tumors

    Institute of Scientific and Technical Information of China (English)

    TAN Jiang-wei; SHEN Bing-hua; DU Wei; LIU Jiang-qing; LU Shi-qiao

    2013-01-01

    Background Older patients with malignant spinal tumors are difficult to treat because they have many co-morbidities including osteoporosis.The purpose of this research is to discuss the technique and clinical outcome of bone cement enhanced pedicle screw fixation combined with vertebroplasty (the Sandwich Procedure) for elderly patients with severe osteoporosis and malignant spinal tumors.Methods This study includes 28 consecutive elderly patients with malignant thoracic or lumbar spinal tumors.There were nine patients with myelomas,and 19 patients with metastatic bone tumors.The Sandwich Procedure began with curettage of the tumor and a vertebroplasty with bone cement (polymethyl methacrylate,PMMA),followed by PMMA enhanced pedicle screw fixation.Patients were evaluated with the visual analogue scale (VAS),oswestry disability index (ODI),American Spinal Cord Injury Association (ASIA) neurological function classification,and the radiographic degree of kyphosis (Cobb angle).Data were analyzed using paired t-test to compare the pre-and post-operative values.The complications,local recurrences,and the survival status were also recorded.Results There was no operative mortality,and the mean operative time was 210 minutes (range 150-250 minutes).The average blood loss was 1550 ml (range 650-3300 ml).The average amount of cement for vertebroplasty was 3.6 ml (range 3-5 ml).The VAS,ODI,and ASIA scores were significantly improved after surgery (P <0.05).However,we found no differences between the pre and post-operative Cobb angles.The shortest survival time was 3 months,and we found no evidence of local recurrence in this group of patients.Conclusion The Sandwich Procedure is a safe operation and provides symptomatic relief in these difficult patients,permitting further treatment with chemotherapy or radiotherapy.

  7. A Paradigm for the Development and Evaluation of Novel Implant Topologies for Bone Fixation: In Vivo Evaluation

    OpenAIRE

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

    2012-01-01

    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 orthopaedic implants and then fabricated select...

  8. Bioabsorbable pins for bone fixation in the less invasive innominate osteotomy.

    Science.gov (United States)

    Dawson, Peter H; O'Briain, David E; Connolly, Paul J; McCormack, Damien

    2014-09-01

    For the less invasive innominate osteotomy for the treatment of developmental dysplasia of the hip, we aim to report radiological outcomes, complication rates and reoperation rates for patients whose bone grafts were secured using bioabsorbable pins. A retrospective study of all patients who underwent less invasive innominate osteotomy for persistent or delayed diagnosis developmental dysplasia of the hip over a period of 2 years from 2008 to 2010 was carried out. A total of 59 hips were identified as having had their bone graft secured with two bioabsorbable pins made from copolymers of L-lactic acid, D-lactic acid and trimethylene carbonate. The average angular correction of the acetabular index in the bioabsorbable group at late follow-up was 16.48° (P<0.0001). Seven percent of patients from the bioabsorbable pin group went on to require reoperation for persistent dysplasia. No patient required reoperation due to implant failure. There was no incidence of postoperative wound infection or other complication requiring medical or surgical intervention. These results demonstrate that the use of bioabsorbable pins to secure the bone graft is as effective and safe as metal fixation. PMID:24911940

  9. Outcome after open reduction and internal fixation of intraarticular fractures of the calcaneum without the use of bone grafts

    Directory of Open Access Journals (Sweden)

    Pendse Aniruddha

    2006-01-01

    Full Text Available Background: Intraarticular fractures of calcaneum are commenest type of calcaneal fractures. Lots of controversies exist about the ideal management for them. The focus is now shifting on operative management by open reduction and internal fixation for these fractures with or without the use of bone grafts. Method: Thirty intraarticular fractures classified by Essex Lopresti radiological classification, were treated by open reduction and fixation. The patients were followed over a mean period of 30 months (25-40 months. Results: All the fractures united at a mean duration of 14 weeks. 86% patients had excellent functional outcome with one patient having fair and one having poor functional outcome. Conclusion: Open reduction and internal fixation with plate is a good method for treatment of intraarticular fractures of calcaneum to achieve anatomical restoration of articular surface under vision, stable fixation, early mobilization and an option for primary subtalar arthrodesis if deemed necessary.

  10. The role of bone SPECT/CT in the evaluation of lumbar spinal fusion with metallic fixation devices

    DEFF Research Database (Denmark)

    Damgaard, Morten; Nimb, Lars; Madsen, Jan L

    2010-01-01

    useful to detect a lack of fixation of the pedicle screws and hence to predict instability of the fused vertebral segments. MATERIALS AND METHODS: A retrospective analysis of 9 patients who were referred to bone scintigraphy, including combined SPECT/CT, due to persistent pain or discomfort after...

  11. [Ectopic osteogenesis in vivo using bone morphogenetic protein-2 derived peptide loaded biodegradable hydrogel].

    Science.gov (United States)

    Zhao, Jingjing; Fang, Zhenhua; Huang, Ruokun; Xiao, Kai; Li, Jing; Xie, Ming; Kan, Wusheng

    2014-08-01

    We investigated the development of an injectable, biodegradable hydrogel composite of poly(trimethylene carbonate)-F127-poly(trimethylene carbonate)(PTMC11-F127-PTMC11 )loaded with bone morphogenetic protein-2 (BMP-2) derived peptide P24 for ectopic bone formation in vivo and evaluated its release kinetics in vitro. Then we evaluated P24 peptide release kinetics from different concentration of PTMC11-F127-PTMC11 hydrogel in vitro using bicinchoninic acid (BCA)assay. P24/ PTMC11-F127-PTMC11 hydrogel was implanted into each rat's erector muscle of spine and ectopic bone formation of the implanted gel in vivo was detected by hematoxylin and eosin stain (HE). PTMC11-F127-PTMC11 hydrogel with concentration more than 20 percent showed sustained slow release for one month after the initial burst release. Bone trabeculae surround the P24/ PTMC11-F127-PTMC11 hydrogel was shown at the end of six weeks by hematoxylin and eosin stain. These results indicated that encapsulated bone morphogenetic protein (BMP-2) derived peptide P24 remained viable in vivo, thus suggesting the potential of PTMC11-F127-PT- MC11 composite hydrogels as part of a novel strategy for localized delivery of bioactive molecules. PMID:25508424

  12. Regional alterations in long bone 85Sr clearance produced by internal fixation devices. Part II. Histomorphometry

    International Nuclear Information System (INIS)

    The effects of each of the surgical stages involved in compression plating on the development of cortical thinning and porosity were assessed in the intact midshaft, stress-shielded femoral segments of adult mongrel dogs 6 months postoperatively. The data were evaluated in terms of a postsurgical tetracycline-based measure of remodeling and terminal 85Sr clearance (SrC) values for the plated segments of bone. Drilling had no effect on any parameter. Screw application was associated with minimal cortical thinning (p less than 0.05), while plate fixation clearly promoted thinning (p less than 0.01) and porosity (p less than 0.05). The percentage of labeled osteons, a measure of remodeling activity, increased only after plate fixation (p less than 0.05), and the labeling patterns suggested that most osteons had formed during the first 4 postsurgical months. That none of these changes were correlated with the 6-month SrC values suggests that the development of plate-induced osteopenia involves disparate histomorphometric time constants, rather than lack of any association

  13. Bone Anchor Fixation in Abdominal Wall Reconstruction: A Useful Adjunct in Suprapubic and Para-iliac Hernia Repair.

    Science.gov (United States)

    Blair, Laurel J; Cox, Tiffany C; Huntington, Ciara R; Ross, Samuel W; Kneisl, Jeffrey S; Augenstein, Vedra A; Heniford, B Todd

    2015-07-01

    Suprapubic hernias, parailiac or flank hernias, and lumbar hernias are difficult to repair and are associated with high-recurrence rates owing to difficulty in obtaining substantive overlap and especially mesh fixation due to bone being a margin of the hernia. Orthopedic suture anchors used for ligament reconstruction have been used to attach prosthetic material to bony surfaces and can be used in the repair of these hernias where suture fixation was impossible. A prospective, single institution study of ventral hernia repairs involving bone anchor mesh fixation was performed. Demographics, operative details, and outcomes data were collected. Twenty patients were identified, with a mean age 53 (range: 35-70 years) and mean body mass index 28.4 kg/m(2) (range 21-38). Ten lumbar, seven suprapubic, and three parailiac hernias were studied. The majority were recurrent hernias (n = 13), with one to seven previously failed repairs. The mean hernia defect size was very large (270 cm(2); range: 56-832 cm(2)) with average mesh size of 1090 cm(2) (range 224-3640 cm(2)). Both Mitek GII (Depuy, Raynham, MA) and JuggerKnot 2.9-mm (Biomet, Biomedical Instruments, Warsaw, IN) anchors were used, with an average of four anchors/case (range: 1-16). Mean operative time was 218 minutes (120-495). There were three minor complications, no operative mortality, and no recurrences during an average follow-up of 24 months. Pelvic bone anchors permit mesh fixation in high-recurrence areas not amenable to traditional suture fixation. The ability to safely and effectively use bone anchor fixation is an essential tool in complex open ventral hernia repair. PMID:26140889

  14. Pedicle screw fixation combined with intervertebral bone grafting for the treatment of thoracolumbar fracture: a report of 24 cases

    Directory of Open Access Journals (Sweden)

    Chuan-lin DU

    2014-01-01

    Full Text Available Objective To explore the clinical effect of pedicle screw fixation combined with intervertebral bone grafting for the treatment of thoracolumbar fractures. Methods The clinical data of 24 cases of unstable and/or bursting thoracolumbar fractures treated with pedicle screw fixation and intervertebral bone grafting from July 2007 to July 2010 were analyzed retrospectively. The 24 patients (18 males and 6 females were aged from 24 to 61 years (mean 31.5 years, in whom 8 with fracture of T12, 9 of L1, 5 of L2, and 2 of L3 vertebral fracture. According to Denis classification, in 8 patients it was compression fracture, and in 16 patients it was burst fracture. According to American Spinal Injury Association (ASIA criteria, 2 patients were classified as grade C, 2 as grade D and 20 as grade E. All of the 24 patients received pedicle screw fixation combined with intervertebral bone grafting to reduce and fix the thoracolumbar fractures using pedicle screw-rod system, and 4 of them received posterior decompression. Results Twenty-two patients were followed-up from 12 to 24 months (mean 18 months. No obvious loss of vertebral height or posterior protuberance was found. There was no evidence of screw loosening or breakage, neither overdistraction of intervertebral space among 22 patients. The Cobb angle was corrected from 15-44 degrees (32.3±7.6 degrees, preoperatively to 0-9.6 degrees (6.6±2.4 degrees as observed at the time of last follow-up. Conclusion Pedicle screw fixation combined with intervertebral bone grafting could reconstruct the mechanical structure of anterior and middle spinal columns, obtain effective intervertebral height and bone union, and long-term spine stability. DOI: 10.11855/j.issn.0577-7402.2013.12.11

  15. Biodegradable poly(epsilon-caprolactone) nanowires for bone tissue engineering applications.

    Science.gov (United States)

    Porter, Joshua R; Henson, Andrew; Popat, Ketul C

    2009-02-01

    Critical-sized defects in bone, whether caused by cancer tumor resection, trauma, or selective surgery have in many cases presented insurmountable challenges to the current gold-standard treatment for bone repair. The primary purpose of a tissue-engineered scaffold is to incite and promote the natural healing process of bone, which does not occur in critical-sized defects. In this work, a solvent-free template synthesis technique was utilized to fabricate uniform arrays of substrate-bound poly(epsilon-caprolactone) (PCL) nanowires. Biodegradation of PCL nanowire surfaces was characterized using scanning electron microscopy (SEM) and matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry. Rat bone marrow-derived mesenchymal stem cells (MSCs) were employed to assess short-term biocompatibility and long-term bioactivity of nanowire surfaces. Short-term cell studies indicated that PCL nanowire surfaces supported enhanced cell adhesion and viability compared with control surfaces. MSCs seeded on nanowire surfaces also displayed increased levels of alkaline phosphatase (ALP) after 1, 2, and 3 weeks in culture. Calcium-phosphate mineralization was substantially accelerated on nanowire surfaces compared to control surfaces as indicated through calcium staining, von Kossa staining, SEM, and electron dispersive spectroscopy (EDS). Increased levels of inter- and extracellular levels of osteocalcin and osteopontin were observed on nanowire surfaces using immunofluorescence techniques after 3 weeks of culture. Considering the simplicity of the presented fabrication technique, capacity for solvent-free encapsulation of bioactive molecules or particles, and enhanced MSC performance on nanowire surfaces, this work presents an excellent foundation for the development of 3-D scaffolds for bone tissue regeneration. PMID:19012962

  16. Biomechanics of bone-fracture fixation by stiffness-graded plates in comparison with stainless-steel plates

    Directory of Open Access Journals (Sweden)

    Ghista Dhanjoo N

    2005-07-01

    Full Text Available Abstract Background In the internal fixation of fractured bone by means of bone-plates fastened to the bone on its tensile surface, an on-going concern has been the excessive stress-shielding of the bone by the excessively-stiff stainless-steel plate. The compressive stress-shielding at the fracture-interface immediately after fracture-fixation delays callus formation and bone healing. Likewise, the tensile stress-shielding of the layer of the bone underneath the plate can cause osteoporosis and decrease in tensile strength of this layer. Method In order to address this problem, we propose to use stiffness-graded plates. Accordingly, we have computed (by finite-element analysis the stress distribution in the fractured bone fixed by composite plates, whose stiffness is graded both longitudinally and transversely. Results It can be seen that the stiffness-graded composite-plates cause less stress-shielding (as an example: at 50% of the healing stage, stress at the fracture interface is compressive in nature i.e. 0.002 GPa for stainless steel plate whereas stiffness graded plates provides tensile stress of 0.002 GPa. This means that stiffness graded plate is allowing the 50% healed bone to participate in loadings. Stiffness-graded plates are more flexible, and hence permit more bending of the fractured bone. This results in higher compressive stresses induced at the fractured faces accelerate bone-healing. On the other hand, away from the fracture interface the reduced stiffness and elastic modulus of the plate causes the neutral axis of the composite structure to be lowered into the bone resulting in the higher tensile stress in the bone-layer underneath the plate, wherein is conducive to the bone preserving its tensile strength. Conclusion Stiffness graded plates (with in-built variable stiffness are deemed to offer less stress-shielding to the bone, providing higher compressive stress at the fractured interface (to induce accelerated healing as

  17. The treatment of femoral bone loss by axial external fixation and susbequent locking plate application: a case report.

    Science.gov (United States)

    Boero, Emanuele; Mogollo, Maria del Amparo Paredes

    2015-12-01

    A 20-year-old man was admitted to our hospital having sustianed bilateral high-energy femoral fractures. The right femoral fracture was an open grade 3B with OTA grade 3 bone loss. The patient had also a brain contusion with a subdural haematoma and a closed fracture of the left clavicle. Initial management included temporarily stabilisation of the femoral fractures wth external fixators and prompt transfer to the intensive care unit. Three weeks later the external fixator of the right femur was converted to an hybrid system, and the fixator of the left side was removed and a reamed intramedullary locking nail was applied. Two months after the accident the patient underwent bone transport (11 cm long) of the right femur with an monolateral external fixation. When the final length was achieved there were knee stiffness (ROM 0° to 30°) and non-union of the docking site. Therefore, the patient underwent a Judet's procedure to treat the knee stiffness and stabilisation of the non united femur with a locking plate (LISS). After the operation the patient started progressive weight bearing. A year after trauma and following union of the femur, the patient underwent soft tissue reconstruction of the anterior side of the thigh with a free vascularised flap. At final follow upo the patient had a good functional recovery with return to his previous occupation. PMID:26738458

  18. Effect of zoledronate acid treatment on osseointegration and fixation of implants in autologous iliac bone grafts in ovariectomized rabbits.

    Science.gov (United States)

    Qi, Mengchun; Hu, Jing; Li, Jianping; Li, Jinyuan; Dong, Wei; Feng, Xiaojie; Yu, Jing

    2012-01-01

    One main problem associated with alveolar bone augmentation in implant dentistry is resorption of grafted bone, which may be further compromised by systemic skeletal disorders such as osteoporosis. Zoledronate acid (ZOL) is the most potent bisphosphonate to treat osteoporosis and therefore it is hypothesized to be able to invert the negative effect of osteoporosis on osseointegration and fixation of dental implants in autologous bone grafts. In this study, 56 rabbits received bilateral ovariectomy (OVX) (40 rabbits) or sham operation (16 rabbits). Three months later, 8 animals from each group were sacrificed for bone mineral density (BMD) examination. Then the remaining animals underwent bilateral autologous iliac bone grafting with simultaneous implantation of titanium implants in tibiae and were divided into 5 groups (n=8): Sham, OVX, Loc-ZOL (local treatment), Sys-ZOL (systemic treatment) and Loc+Sys-ZOL (local plus systemic) group. At 3 months after implantation, all animals were sacrificed and specimens were harvested for examinations. Both BMD and histological examinations of femurs showed osteoporotic changes after ovariectomy, while systemic treatment with ZOL restored mineralized bone. Micro-CT examination demonstrated that OVX group showed significant decrease of mineralized bone and implant-bone contact when compared with sham control, whereas both systemic and local treatments of ZOL significantly increased mineralized bone and implant-bone contact in ovariectomized animals. However, the best effects were observed in Loc+Sys-ZOL group (combined use of ZOL) and most of bone indices were similar to (IBCR, p>0.05) or higher than (BV/TV, Conn.D and Tb.N) (peffects were also confirmed by histomorphometric analysis of bone indices on implant-bone contact and mineralized bone. In addition, biomechanical testing further supported the beneficial effect of ZOL treatment and maximal removal torque of titanium implants was observed in Loc+Sys-ZOL group. In

  19. Deformation measurement of the bone fixed with external fixator using holographic interferometry

    Science.gov (United States)

    Kojima, Arata; Ogawa, Ryokei; Izuchi, N.; Yamamoto, Manabu; Nishimoto, T.; Matsumoto, Toshiro

    1991-08-01

    Mechanical properties of tibia fixed with an external fixative device (external fixator) were investigated under some simulated loading conditions. Deformation measurements were performed using double exposure holographic interferometry and real-time holographic interferometry. According to the results of the holographic interferometry, strains on the fixation pins and rods were also measured using strain gauges. The results showed that, with most types of external fixator, dislocations of both fractured ends were mainly caused by decrease in strength of the fixation pins. With increase in strength of fixation pins, angular deformation of the rod was more obvious. Increase in the strength of the rod was not always effective in decreasing dislocation of both fractured ends. Changes in bracing technique with marked change in rigidity of external fixator were useful to decrease dislocation of both fractured ends.

  20. Titanium-alloy enhances bone-pedicle screw fixation: mechanical and histomorphometrical results of titanium-alloy versus stainless steel

    OpenAIRE

    Christensen, F.B.; Dalstra, M.; Sejling, F.; Overgaard, S.; Bünger, C.

    2000-01-01

    Several types of pedicle screw systems have been utilized to augment lumbar spine fusion. The majority of these systems are made of stainless steel (Ss), but titanium-alloy (Ti-alloy) devices have recently been available on the market. Ti-alloy implants have several potential advantages over Ss ones. High bioactivity and more flexibility may improve bone ingrowth and mechanical fixation, and the material also offers superior magnetic resonance imaging (MRI) and computed tomography (CT) resolu...

  1. 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 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...

  2. Experimental and Numerical Analyses of the Pull-out Response of a Steel Post/Bovine Bone Cementless Fixation

    Institute of Scientific and Technical Information of China (English)

    Khaled Gammoudi; Mohamed Kharrat; Maher Dammak

    2012-01-01

    Effect of initial interference fit on pull-out strength in cementless fixation between bovine tibia and smooth stainless steel post was investigated in this study.Compressive behavior of bovine spongious bone was studied using mechanical testing in order to evaluate the elastic-plastic properties in different regions of the proximal tibia.Friction tests were carried out in the aim to evaluate the friction behavior of the contact between bovine spongious bone and stainless steel.A cylindrical stainless steel post inserted in a pre-drilled bovine tibia with an initial interference fit was taken as an in vitro model to assess the contribution of post fixation to the initial stability of the Total Knee Arthroplasty (TKA) tibial component.Pull-out experiments were carried out for different initial interference fits.Finite Element Models (FEM) using local elastic-plastic properties of the bovine bone were developed for the analysis of the experimental ultimate pull-out force results.At the post/bone interface,Coulomb friction was considered in the FEM calculations with pressure-dependent friction coefficient.It was found that the FEM results of the ultimate force are in good agreement with the experimental results.The analysis of the FEM interfacial stresses indicates that the micro-slip initiation depends on the local bone properties.

  3. Selenium-Substituted Hydroxyapatite/Biodegradable Polymer/Pamidronate Combined Scaffold for the Therapy of Bone Tumour

    Directory of Open Access Journals (Sweden)

    Ewa Oledzka

    2015-09-01

    Full Text Available The present study evaluated a new concept of combined scaffolds as a promising bone replacement material for patients with a bone tumour or bone metastasis. The scaffolds were composed of hydroxyapatite doped with selenium ions and a biodegradable polymer (linear or branched, and contained an active substance—bisphosphonate. For this purpose, a series of biodegradable polyesters were synthesized through a ring-opening polymerization of ε-caprolactone or d,l-lactide in the presence of 2-hydroxyethyl methacrylate (HEMA or hyperbranched 2,2-bis(hydroxymethylpropionic acid polyester-16-hydroxyl (bis-MPA initiators, substances often used in the synthesis of medical materials. The polymers were obtained with a high yield and a number-average molecular weight up to 45,300 (g/mol. The combined scaffolds were then manufactured by a direct compression of pre-synthesized hydroxyapatite doped with selenite or selenate ions, obtained polymer and pamidronate as a model drug. It was found that the kinetic release of the drug from the scaffolds tested in vitro under physiological conditions is strongly dependent on the physicochemical properties and average molecular weight of the polymers. Furthermore, there was good correlation with the hydrolytic biodegradation results of the scaffolds fabricated without drug. The preliminary findings suggest that the fabricated combined scaffolds could be effectively used for the sustained delivery of bioactive molecules at bone defect sites.

  4. Employment of the adhesive buthyl-2-cyanoacrylate in the fixation of bone fragments in femural fractures in dogs. Radiologic study

    International Nuclear Information System (INIS)

    The butyl-2-cyanoacrylate adhesive was utilized in the fixation of bone fragments in femoral fractures in 30 clinically healthy dogs of both sexes. All animals were anesthetized with sodium pentobarbital and the left femur exposed and fractured at the middle third of the bone. A triangular bone fragment, approximately of 2.0 cm in length was taken off from the proximal fragment of the femur. The fracture was immediately reduced and immobilized using an intramedular Steinman pin. The bone fragment was then reintroduced in the same position and glued on with the adhesive butyl-2-cyanoacrylate, applied in droplets at a distance of 8 mm approximately. Healing was assessed through radiographs at 10 day intervals, when it was observed, in all animals, the bone fragment in place right after the surgical procedure. At the end of the experiment 6.67% of animals showed the bone fragment shifted from the focus of fracture. In 30% of the animals the fracture did not consolidate

  5. Enhancement of osteogenesis and biodegradation control by brushite coating on Mg-Nd-Zn-Zr alloy for mandibular bone repair.

    Science.gov (United States)

    Guan, Xingmin; Xiong, Meiping; Zeng, Feiyue; Xu, Bin; Yang, Lingdi; Guo, Han; Niu, Jialin; Zhang, Jian; Chen, Chenxin; Pei, Jia; Huang, Hua; Yuan, Guangyin

    2014-12-10

    To diminish incongruity between bone regeneration and biodegradation of implant magnesium alloy applied for mandibular bone repair, a brushite coating was deposited on a matrix of a Mg-Nd-Zn-Zr (hereafter, denoted as JDBM) alloy to control the degradation rate of the implant and enhance osteogenesis of the mandible bone. Both in vitro and in vivo evaluations were carried out in the present work. Viability and adhesion assays of rabbit bone marrow mesenchyal stem cells (rBM-MSCs) were applied to determine the biocompatibility of a brushite-coated JDBM alloy. Osteogenic gene expression was characterized by quantitative real-time polymerase chain reaction (RT-PCR). Brushite-coated JDBM screws were implanted into mandible bones of rabbits for 1, 4, and 7 months, respectively, using 316L stainless steel screws as a control group. In vivo biodegradation rate was determined by synchrotron radiation X-ray microtomography, and osteogenesis was observed and evaluated using Van Gieson's picric acid-fuchsin. Both the naked JDBM and brushite-coated JDBM samples revealed adequate biosafety and biocompatibility as bone repair substitutes. In vitro results showed that brushite-coated JDBM considerably induced osteogenic differentiation of rBM-MSCs. And in vivo experiments indicated that brushite-coated JDBM screws presented advantages in osteoconductivity and osteogenesis of mandible bone of rabbits. Degradation rate was suppressed at a lower level at the initial stage of implantation when new bone tissue formed. Brushite, which can enhance oeteogenesis and partly control the degradation rate of an implant, is an appropriate coating for JDBM alloys used for mandibular repair. The Mg-Nd-Zn-Zr alloy with brushite coating possesses great potential for clinical applications for mandibular repair. PMID:25343576

  6. Heterotopic Ossification around the Knee after Internal Fixation of a Complex Tibial Plateau Fracture Combined with the Use of Demineralized Bone Matrix (DBM: A Case Report

    Directory of Open Access Journals (Sweden)

    1.\tSjoerd P.F.T. Nota

    2014-10-01

    Full Text Available Demineralized bone matrix has been successfully commercialized as an alternative bone graft material that not only can function as filler but also as an osteoinductive graft. Numerous studies have confirmed its beneficial use in clinical practice. Heterotopic ossification after internal fixation combined with the use of demineralized bone matrix has not been widely reported. In this paper we describe a 39 year old male who sustained a complex articular fracture that developed clinically significant heterotopic ossification after internal fixation with added demineralized bone matrix. Although we cannot be sure that there is a cause-and-effect relation between demineralized bone matrix and the excessive heterotopic ossification seen in our patient, it seems that some caution in using demineralised bone matrix in similar cases is warranted. Also, given the known inter- and intraproduct variability, the risks and benefits of these products should be carefully weighed.

  7. In vitro characterization and biomechanical optimization of a biodegradable particulate composite bone cement.

    Science.gov (United States)

    Gerhart, T N; Miller, R L; Kleshinski, S J; Hayes, W C

    1988-11-01

    We have developed a biodegradable particulate composite bone cement and used in vitro and in vivo methods for studying its suitability for orthopaedic applications. The composite matrix consists of gelatin, water, and sodium salicylate. The particulate phase is made up of powdered and particulate (355-600 microns diameter) tricalcium phosphate. Paraformaldehyde (0.1% to 0.5% by weight) is used as a matrix cross-linking agent. The effects of incubation time, particulate volume fraction, density of the individual particles, water content, concentration of crosslinking agent, and freeze-drying on the unconfined compressive strength and modulus of the particulate composite were measured. Compressive strengths of 7 MPa and moduli of 65 MPa could be achieved. Mechanical properties depended critically upon the water content of the particulate composite, with values of strength and modulus decreasing rapidly outside a range of 10-14% of specimen dry weight. High-density tricalcium phosphate particulate produced cement with twice the strength found with porous particulate. In a companion study we document in vivo performance of this particulate composite in an animal model system. PMID:3241009

  8. Nanoporous metals for biodegradable implants: Initial bone mesenchymal stem cell adhesion and degradation behavior.

    Science.gov (United States)

    Heiden, Michael; Huang, Sabrina; Nauman, Eric; Johnson, David; Stanciu, Lia

    2016-07-01

    Nanostructured Fe-Mn and Fe-Mn-Zn metal scaffolds were generated through a well-controlled selective leaching process in order to fulfill the growing demand for adjustable degradation rates and improved cellular response of resorbable materials. Mouse bone marrow mesenchymal stem cells (D1 ORL UVA) were seeded onto eleven, carefully chosen nanoporous surfaces for 24 h in vitro. Using a combination of fluorescence microscopy, scanning electron microscopy (SEM), and an MTS assay, it was discovered that scaffolds with nanoscale roughened surfaces had increased cell attachment by up to 123% compared to polished smooth Fe-Mn surfaces. Significant cell spreading and construction of cell multilayers were also apparent after 24 h, suggesting better adhesion. Additionally, static electrochemical polarization experiments revealed an improvement of up to 26% in the actual rate of biodegradation for Fe-Mn surface-modified materials. However, any residual concentration of zinc after leaching was shown to slightly increase corrosion resistance. The results demonstrate that selectively leached, nanostructured Fe-Mn surfaces have the potential of being tailored to a diverse set of transient implant scenarios, while also effectively boosting overall biocompatibility, initial cell attachment, and degradation rate. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1747-1758, 2016. PMID:26990484

  9. Bone allograft and implant fixation tested under influence of bio-burden reduction, periosteal augmentation and topical antibiotics. Animal experimental studies.

    Science.gov (United States)

    Barckman, Jeppe

    2014-01-01

    Loosening of an artificial joint prosthesis is a painful and debilitating condition that can be treated only by re-operation. Re-operations accounted for approximately 15% of all hip replacement operations performed in Denmark between the year 1995 and 2010. The process of loosening is often accompanied by destructive inflammation and osteolysis, which leads to insufficient bone stock that often requires extensive bone grafting. Impacted morselized bone graft is a well-established method for improving the amount and quality of bone stock that ensures sufficient stability and anchorage of the revision implants. Among bone graft options, the autologous bone graft is considered the gold standard. It is naturally biocompatible, but its use in revision surgery is curtailed by its limited volume and by considerable donor site morbidity. Allograft bone is readily available and is the most commonly used graft material. However, it has been shown that the incorporation of allograft bone into the host bone is not always complete, and substantial fibrous tissue formation has been described. A reason for this may be that allograft bone is a foreign tissue, which, contrary to autogenic bone, may induce an immunogenic response that leads to increased fibrous tissue formation. Furthermore, the fresh-frozen allograft has minimal osteoinductive and no osteogenic capacity. The studies in this thesis have investigated ways of improving the incorporation of allograft bone by adding osteoinductive cells from the periosteum and reducing the immunogenic load of the allograft bone by rinsing. Furthermore, the impact of antibiotic protection of the bone graft has been evaluated. The same experimental implant model was used in all three studies. This model enables evaluation of early implant fixation and osseointegration of an uncemented implant surrounded by impacted morselized bone graft. Unloaded gap implants were inserted into the metaphysis of the proximal tibia (Study I) and distal

  10. Demineralized bone matrix and human cancellous bone enhance fixation of porous-coated titanium implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2013-01-01

    Allogenic bone graft has been considered the gold standard in connection with bone graft material in revision joint arthroplasty. However, the lack of osteogenic potential and the risk of disease transmission are clinical challenges. The use of osteoinductive materials, such as demineralized bone...

  11. Aluminum-free glass-ionomer bone cements with enhanced bioactivity and biodegradability

    International Nuclear Information System (INIS)

    Al-free glasses of general composition 0.340SiO2:0.300ZnO:(0.250-a-b)CaO:aSrO:bMgO:0.050Na2O:0.060P2O5 (a, b = 0.000 or 0.125) were synthesized by melt quenching and their ability to form glass-ionomer cements was evaluated using poly(acrylic acid) and water. We evaluated the influence of the poly(acrylic acid) molecular weight and glass particle size in the cement mechanical performance. Higher compressive strength (25 ± 5 MPa) and higher compressive elastic modulus (492 ± 17 MPa) were achieved with a poly(acrylic acid) of 50 kDa and glass particle sizes between 63 and 125 μm. Cements prepared with glass formulation a = 0.125 and b = 0.000 were analyzed after immersion in simulated body fluid; they presented a surface morphology consistent with a calcium phosphate coating and a Ca/P ratio of 1.55 (similar to calcium-deficient hydroxyapatite). Addition of starch to the cement formulation induced partial degradability after 8 weeks of immersion in phosphate buffer saline containing α-amylase. Micro-computed tomography analysis revealed that the inclusion of starch increased the cement porosity from 35% to 42%. We were able to produce partially degradable Al-free glass-ionomer bone cements with mechanical performance, bioactivity and biodegradability suitable to be applied on non-load bearing sites and with the appropriate physical characteristics for osteointegration upon partial degradation. Zn release studies (concentrations between 413 μM and 887 μM) evidenced the necessity to tune the cement formulations to reduce the Zn concentration in the surrounding environment. Highlights: ► We developed partially degradable, bioactive, Al-free glass-ionomer cements (GICs). ► Enhanced mechanical behavior was achieved using 63–125 μm glass particle size range. ► The highest mechanical resistance was obtained using poly(acrylic acid) of 50 kDa. ► Biodegradation was successfully tuned to start 8 weeks after GIC preparation. ► Zn release should be tuned to

  12. Aluminum-free glass-ionomer bone cements with enhanced bioactivity and biodegradability

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Filipa O.; Pires, Ricardo A., E-mail: rpires@dep.uminho.pt; Reis, Rui L.

    2013-04-01

    Al-free glasses of general composition 0.340SiO{sub 2}:0.300ZnO:(0.250-a-b)CaO:aSrO:bMgO:0.050Na{sub 2}O:0.060P{sub 2}O{sub 5} (a, b = 0.000 or 0.125) were synthesized by melt quenching and their ability to form glass-ionomer cements was evaluated using poly(acrylic acid) and water. We evaluated the influence of the poly(acrylic acid) molecular weight and glass particle size in the cement mechanical performance. Higher compressive strength (25 ± 5 MPa) and higher compressive elastic modulus (492 ± 17 MPa) were achieved with a poly(acrylic acid) of 50 kDa and glass particle sizes between 63 and 125 μm. Cements prepared with glass formulation a = 0.125 and b = 0.000 were analyzed after immersion in simulated body fluid; they presented a surface morphology consistent with a calcium phosphate coating and a Ca/P ratio of 1.55 (similar to calcium-deficient hydroxyapatite). Addition of starch to the cement formulation induced partial degradability after 8 weeks of immersion in phosphate buffer saline containing α-amylase. Micro-computed tomography analysis revealed that the inclusion of starch increased the cement porosity from 35% to 42%. We were able to produce partially degradable Al-free glass-ionomer bone cements with mechanical performance, bioactivity and biodegradability suitable to be applied on non-load bearing sites and with the appropriate physical characteristics for osteointegration upon partial degradation. Zn release studies (concentrations between 413 μM and 887 μM) evidenced the necessity to tune the cement formulations to reduce the Zn concentration in the surrounding environment. Highlights: ► We developed partially degradable, bioactive, Al-free glass-ionomer cements (GICs). ► Enhanced mechanical behavior was achieved using 63–125 μm glass particle size range. ► The highest mechanical resistance was obtained using poly(acrylic acid) of 50 kDa. ► Biodegradation was successfully tuned to start 8 weeks after GIC preparation. ► Zn

  13. The factors affecting outcome after non-vascular bone grafting and internal fixation for nonunion of the scaphoid.

    Science.gov (United States)

    Ramamurthy, C; Cutler, L; Nuttall, D; Simison, A J M; Trail, I A; Stanley, J K

    2007-05-01

    This study identified variables which influence the outcome of surgical management on 126 ununited scaphoid fractures managed by internal fixation and non-vascular bone grafting. The site of fracture was defined by a new method: the ratio of the length of the proximal fragment to the sum of the lengths of both fragments, calculated using specific views in the plain radiographs. Bone healing occurred in 71% (89) of cases. Only the site of nonunion (p = 1 x 10(-6)) and the delay to surgery (p = 0.001) remained significant on multivariate analysis. The effect of surgical delay on the probability of union increased as the fracture site moved proximally. A prediction model was produced by stepwise logistic regression analysis, enabling the surgeon to predict the success of surgery where the site of the nonunion and delay to surgery is known. PMID:17540748

  14. Osteogenic potential of porous {beta}-tricalcium phosphate ({beta}-TCP) combined with cultured bone. Tissue engineered bone using a biodegradable material as a scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Fu, S.; Yamada, Y.; Honda, M.; Ueda, M. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Yoshikawa, T. [Nara Medical Univ. (Japan). First Dept. of Pathology; Hibino, Y.; Hata, K. [Nagoya Univ. (Japan). Dept. of Tissue Engineering; Niimi, A. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Chunichi Hospital (Japan). Dept. of Oral and Maxillofacial Surgery; Okazaki, Y. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Nagoya Univ. (Japan). Dept. of Tissue Engineering

    2001-07-01

    Recently, the tissue engineering approach has widespread attention for regeneration. The present study was undertaken to evaluate whether biodegradable porous {beta}-tricalcium phosphate ({beta}-TCP) can be used as a scaffold for cultured bone marrow cells or not. Marrow cells were obtained from bone shaft of rat femur and cultured in a standard medium for 10 days, then trypsinized to combine cells with ceramics. An additional subculture was done for cells/ceramics composite in a standard medium with the addition of {beta}-glycerophosphate, ascorbic acid and dexamethason. The 20 day subcultured composites were implanted into subcutaneous sites of syngeneic rats. These implants were harvested at 4 and 8 weeks postimplantation, and prepared for the histological analysis. In the histological analysis of composites at 4 weeks postimplantation, active bone formation could be found in the composites. The bone formation was evidenced by active osteoblast lining on the surfaces of bone. At 8 weeks, more extensive bone formation was observed in the composites. These results suggested that beta-TCP could play a role as scaffold of tissueengineered bone derived from marrow cells. (orig.)

  15. Histological analysis of cells and matrix mineralization of new bone tissue induced in rabbit femur bones by Mg-Zr based biodegradable implants.

    Science.gov (United States)

    Ragamouni, Sravanthi; Kumar, Jerald Mahesh; Mushahary, Dolly; Nemani, Harishankar; Pande, Gopal

    2013-09-01

    The biological efficacy of bone inducing implant materials in situ can be assessed effectively by performing histological analysis. We studied the peri-implant bone regeneration around two types of biodegradable magnesium-zirconium alloys, Mg-5Zr and Mg-Zr-2Sr, using histological, histochemical and immunohistochemical methods in the femur of New Zealand White strain rabbits. Our study includes three animal groups: (a) Mg-5Zr, (b) Mg-Zr-2Sr and (c) control. In each group three animals were used and in groups 'a' and 'b' the respective alloys were implanted in cavities made at the distal ends of the femur; control animals were left without implants to observe natural bone healing. Qualitative assessment of the cellularity and matrix mineralization events of the newly formed bone tissue was done at three months after implantation by histological methods in methyl methacrylate embedded tissue without decalcifying the bone. Quantitative mineral content and density of the new bone (NB) were evaluated by the statistical analysis of dual energy X-ray absorptiometry (DXA) data obtained from three animals in each experimental group. Based on our analysis we conclude that Mg-Zr-2Sr alloy showed better osseointegration of the newly formed bone with the implant surface. Our methodology of studying peri-implant osteoinduction of degradable implants using low temperature methyl methacrylate embedding resin can be useful as a general method for determining the bio-efficacy of implant materials. PMID:23628266

  16. Effect of implantation of biodegradable magnesium alloy on BMP-2 expression in bone of ovariectomized osteoporosis rats

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yue, E-mail: 373073766@qq.com [Liaoning Medical University, 40 Songpo Road, Jinzhou, 121000 (China); Ren, Ling, E-mail: lren@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016 (China); Liu, Chang, E-mail: meixifan1971@163.com [Liaoning Medical University, 40 Songpo Road, Jinzhou, 121000 (China); Yuan, Yajiang, E-mail: yuan925@163.com [Liaoning Medical University, 40 Songpo Road, Jinzhou, 121000 (China); Lin, Xiao, E-mail: linx@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016 (China); Tan, Lili, E-mail: lltan@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016 (China); Chen, Shurui, E-mail: 272146792@qq.com [Liaoning Medical University, 40 Songpo Road, Jinzhou, 121000 (China); Yang, Ke, E-mail: kyang@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016 (China); Mei, Xifan, E-mail: meixifan1971@163.com [Liaoning Medical University, 40 Songpo Road, Jinzhou, 121000 (China)

    2013-10-01

    The study was focused on the implantation of a biodegradable AZ31 magnesium alloy into the femoral periosteal of the osteoporosis modeled rats. The experimental results showed that after 4 weeks implantation of AZ31 alloy in the osteoporosis modeled rats, the expression of BMP-2 in bone tissues of the rats was much enhanced, even higher than the control group, which should promote the bone formation and be beneficial for reducing the harmful effect of osteoporosis. Results of HE stains showed that the implantation of AZ31 alloy did not have obvious pathological changes on both the liver and kidney of the animal. - Highlights: • Mg alloy greatly increased expression of BMP-2 in osteoporosis modeled rat bone. • Mg alloy showed good biological safety. • Mg alloy is beneficial for reducing the symptom of osteoporosis.

  17. Effect of implantation of biodegradable magnesium alloy on BMP-2 expression in bone of ovariectomized osteoporosis rats

    International Nuclear Information System (INIS)

    The study was focused on the implantation of a biodegradable AZ31 magnesium alloy into the femoral periosteal of the osteoporosis modeled rats. The experimental results showed that after 4 weeks implantation of AZ31 alloy in the osteoporosis modeled rats, the expression of BMP-2 in bone tissues of the rats was much enhanced, even higher than the control group, which should promote the bone formation and be beneficial for reducing the harmful effect of osteoporosis. Results of HE stains showed that the implantation of AZ31 alloy did not have obvious pathological changes on both the liver and kidney of the animal. - Highlights: • Mg alloy greatly increased expression of BMP-2 in osteoporosis modeled rat bone. • Mg alloy showed good biological safety. • Mg alloy is beneficial for reducing the symptom of osteoporosis

  18. A comparative study on the in vivo degradation of poly(L-lactide) based composite implants for bone fracture fixation

    Science.gov (United States)

    Wang, Zongliang; Wang, Yu; Ito, Yoshihiro; Zhang, Peibiao; Chen, Xuesi

    2016-02-01

    Composite of nano-hydroxyapatite (n-HAP) surface grafted with poly(L-lactide) (PLLA) (g-HAP) showed improved interface compatibility and mechanical property for bone fracture fixation. In this paper, in vivo degradation of n-HAP/PLLA and g-HAP/PLLA composite implants was investigated. The mechanical properties, molecular weight, thermal properties as well as crystallinity of the implants were measured. The bending strength of the n- and g-HAP/PLLA composites showed a marked reduction from an initial value of 102 and 114 MPa to 33 and 24 MPa at 36 weeks, respectively. While the bending strength of PLLA was maintained at 80 MPa at 36 weeks compared with initial value of 107 MPa. The impact strength increased over time especially for the composites. Significant differences in the molecular weight were seen among all the materials and g-HAP/PLLA appeared the fastest rate of decrease than others. Environmental scanning electron microscope (ESEM) results demonstrated that an apparently porous morphology full of pores and hollows were formed in the composites. The results indicated that the in vivo degradation of PLLA could be accelerated by the g-HAP nanoparticles. It implied that g-HAP/PLLA composites might be a candidate for human non-load bearing bone fracture fixation which needs high initial strength and fast degradation rate.

  19. Finite element analysis of osteosynthesis screw fixation in the bone stock: an appropriate method for automatic screw modelling.

    Science.gov (United States)

    Wieding, Jan; Souffrant, Robert; Fritsche, Andreas; Mittelmeier, Wolfram; Bader, Rainer

    2012-01-01

    The use of finite element analysis (FEA) has grown to a more and more important method in the field of biomedical engineering and biomechanics. Although increased computational performance allows new ways to generate more complex biomechanical models, in the area of orthopaedic surgery, solid modelling of screws and drill holes represent a limitation of their use for individual cases and an increase of computational costs. To cope with these requirements, different methods for numerical screw modelling have therefore been investigated to improve its application diversity. Exemplarily, fixation was performed for stabilization of a large segmental femoral bone defect by an osteosynthesis plate. Three different numerical modelling techniques for implant fixation were used in this study, i.e. without screw modelling, screws as solid elements as well as screws as structural elements. The latter one offers the possibility to implement automatically generated screws with variable geometry on arbitrary FE models. Structural screws were parametrically generated by a Python script for the automatic generation in the FE-software Abaqus/CAE on both a tetrahedral and a hexahedral meshed femur. Accuracy of the FE models was confirmed by experimental testing using a composite femur with a segmental defect and an identical osteosynthesis plate for primary stabilisation with titanium screws. Both deflection of the femoral head and the gap alteration were measured with an optical measuring system with an accuracy of approximately 3 µm. For both screw modelling techniques a sufficient correlation of approximately 95% between numerical and experimental analysis was found. Furthermore, using structural elements for screw modelling the computational time could be reduced by 85% using hexahedral elements instead of tetrahedral elements for femur meshing. The automatically generated screw modelling offers a realistic simulation of the osteosynthesis fixation with screws in the adjacent

  20. Finite element analysis of osteosynthesis screw fixation in the bone stock: an appropriate method for automatic screw modelling.

    Directory of Open Access Journals (Sweden)

    Jan Wieding

    Full Text Available The use of finite element analysis (FEA has grown to a more and more important method in the field of biomedical engineering and biomechanics. Although increased computational performance allows new ways to generate more complex biomechanical models, in the area of orthopaedic surgery, solid modelling of screws and drill holes represent a limitation of their use for individual cases and an increase of computational costs. To cope with these requirements, different methods for numerical screw modelling have therefore been investigated to improve its application diversity. Exemplarily, fixation was performed for stabilization of a large segmental femoral bone defect by an osteosynthesis plate. Three different numerical modelling techniques for implant fixation were used in this study, i.e. without screw modelling, screws as solid elements as well as screws as structural elements. The latter one offers the possibility to implement automatically generated screws with variable geometry on arbitrary FE models. Structural screws were parametrically generated by a Python script for the automatic generation in the FE-software Abaqus/CAE on both a tetrahedral and a hexahedral meshed femur. Accuracy of the FE models was confirmed by experimental testing using a composite femur with a segmental defect and an identical osteosynthesis plate for primary stabilisation with titanium screws. Both deflection of the femoral head and the gap alteration were measured with an optical measuring system with an accuracy of approximately 3 µm. For both screw modelling techniques a sufficient correlation of approximately 95% between numerical and experimental analysis was found. Furthermore, using structural elements for screw modelling the computational time could be reduced by 85% using hexahedral elements instead of tetrahedral elements for femur meshing. The automatically generated screw modelling offers a realistic simulation of the osteosynthesis fixation with

  1. Acceleration and holographic studies on different types of dynamization of external fixators of the bones

    Science.gov (United States)

    Podbielska, Halina; Kasprzak, Henryk T.; Voloshin, Arkady S.; Pennig, Dietmar; von Bally, Gert

    1992-08-01

    The unilateral axially dynamic fixator (Orthofix) was mounted on a sheep tibial shaft. Three fixation modes: static, dynamic controlled, and dynamic free were examined by means of double exposure holographic interferometry. Simultaneously, the acceleration was measured by an accelerometer and displayed on the monitor together with loading characteristics. The first exposure was made before the acting force was applied to the tibia plateau. The second one after the moment when the acceleration wave started to propagate through the specimen. We stated that in the case of dynamization less torsion occurs at the fracture site. So far, we have not been able to determine any correlation between results of holographic and accelerometric measurements.

  2. BOHLER'S ANGLE: CORRELATION WITH OUTCOME IN DISPLACED INTRA-ARTICULAR CALCANEAL FRACTURES TREATED WITH LOCKING COMPRESSION PLATE FIXATION WITH AND WITHOUT BONE GRAFTING

    OpenAIRE

    Deepak P; Eknath D; Vijayanand; Satish

    2014-01-01

    BOHLER'S ANGLE: correlation with outcome in displaced intra-articular calcaneal fractures Treated with locking compression Plate Fixation with and without bone grafting. AIMS: The aim is an accurate reduction of the fracture with reconstruction of Bohler’s angle, length and axis and sub talar joint surface. To determine whether autologous bone graft supplementation is beneficial in achieving and maintaining restoration of Calcaneal height and anatomic reduction. SETTINGS AND ...

  3. Depot injectable biodegradable nanoparticles loaded with recombinant human bone morphogenetic protein-2: preparation, characterization, and in vivo evaluation

    Directory of Open Access Journals (Sweden)

    Hassan AH

    2015-07-01

    Full Text Available Ali Habiballah Hassan,1 Khaled Mohamed Hosny,2,3 Zuahir A Murshid,1 Adel Alhadlaq,4 Ahmed Alyamani,5 Ghada Naguib6 1Department of Orthodontics, Faculty of Dentistry, 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 3Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Beni Suef University, Beni Suef, Egypt; 4Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, Riyadh, 5Department of Oral Surgery, 6Department of Restorative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia Objective: The aim of this study is to utilize the biocompatibility characteristics of biodegradable polymers, viz, poly lactide-co-glycolide (PLGA and polycaprolactone (PCL, to prepare sustained-release injectable nanoparticles (NPs of bone morphogenetic protein-2 (BMP-2 for the repair of alveolar bone defects in rabbits. The influence of formulation parameters on the functional characteristics of the prepared NPs was studied to develop a new noninvasive injectable recombinant human BMP-2 (rhBMP-2 containing grafting material for the repair of alveolar bone clefts.Materials and methods: BMP-2 NPs were prepared using a water-in-oil-in-water double-emulsion solvent evaporation/extraction method. The influence of molar ratio of PLGA to PCL on a suitable particle size, encapsulation efficiency, and sustained drug release was studied. Critical size alveolar defects were created in the maxilla of 24 New Zealand rabbits divided into three groups, one of them treated with 5 µg/kg of rhBMP-2 NP formulations.Results: The results found that NPs formula prepared using blend of PLGA and PCL in 4:2 (w/w ratio showed the best sustained-release pattern with lower initial burst, and showed up to 62.7% yield, 64.5% encapsulation efficiency, 127 nm size, and more than 90% in vitro release. So, this formula was selected for

  4. Changes in the computed tomography (pixel) value of mandibular ramus bone and fixation screws after sagittal split ramus osteotomy.

    Science.gov (United States)

    Ueki, K; Moroi, A; Iguchi, R; Kosaka, A; Ikawa, H; Yoshizawa, K

    2015-11-01

    The purpose of this retrospective study was to evaluate the changes in computed tomography (CT) values of ramus bone and screws after sagittal split ramus osteotomy (SSRO) setback surgery. The subjects were 64 patients (128 sides) who underwent bilateral SSRO setback surgery. They were divided into six groups according to the fixation plate type used and the use or not of self-setting α-tricalcium phosphate (Biopex): group 1: titanium plate and screws; group 2: titanium plate and screws with Biopex; group 3: poly-l-lactic acid (PLLA) plate and screws; group 4: PLLA plate and screws with Biopex; group 5: uncalcined and unsintered hydroxyapatite particles and poly-l-lactic acid (uHA/PLLA) plate and screws; group 6: PLLA/uHA plate and screws with Biopex. CT values (pixel values) of the lateral cortex, medial cortex, osteotomy site, and screws were measured preoperatively, immediately after surgery, and 1 year postoperatively using horizontal CT images at the mandibular foramen taken parallel to the Frankfort horizontal plane. There were significant differences in the time-course change of pixel values for the lateral cortex (Pmaterial may affect bone quality during the process of bone healing after SSRO. PMID:26139563

  5. Regional alterations in long bone produced by internal fixation devices. Part I. 85Sr clearance

    International Nuclear Information System (INIS)

    We examined the effect of rigid plate application on the radiostrontium clearance of the intact canine femur at 6 months. We examined each of the component surgical steps. We calculated the clearance both for the whole bone and for each of the five transverse sections of the whole bone. Screw application, but not drilling, increased the clearance in the segment about the screw holes. Plate application produced an increase in the segment beneath the plate as well as around the screws and in the whole bone. These changes are accomplished not only by an absolute increase in clearance to the middle three segments, but by a relative diminution in clearance by the most proximal and distal segments. The histomorphometric changes in long bones following rigid plating may be accompanied by regional increases in bone blood flow

  6. Radiological Evaluation of the Initial Fixation between Cortical Bone Trajectory and Conventional Pedicle Screw Technique for Lumbar Degenerative Spondylolisthesis

    Science.gov (United States)

    Iwatsuki, Koichi; Ohnishi, Yu-Ichiro; Yoshimine, Toshiki

    2016-01-01

    Study Design Retrospective study. Purpose To compare initial fixation using the cortical bone trajectory (CBT) technique versus conventional pedicle screws (PS) in radiographs of postsurgical lumbar degenerative spondylolisthesis. Overview of Literature Few reports have documented the holding strength of CBT technique for spondylolisthesis cases. Methods From October 2009 to June 2014, 21 cases of degenerative spondylolisthesis were surgically treated in our institution. Ten were treated with conventional PS technique and 11 of with CBT technique. Mean lumbar lordosis and percent slippage were evaluated preoperatively, immediately after surgery, and 6 months and 1 year postoperatively using radiographs. We also investigated percent loss of slip reduction. Results There were statistically significant differences between preoperative percent slippage and postoperative slippage in both PS and CBT procedures over 1 year, and both techniques showed good slip reduction. On the other hand, lumbar lordosis did not change significantly in either the PS or CBT groups over 1 year. Conclusions CBT technique showed similarly good initial fixation compared with the PS procedure in the treatment of lumbar degenerative spondylolisthesis. PMID:27114765

  7. Biomechanical and finite element analyses of bone cement-Injectable cannulated pedicle screw fixation in osteoporotic bone.

    Science.gov (United States)

    Liu, Yaoyao; Xu, Jianzhong; Sun, Dong; Luo, Fei; Zhang, Zehua; Dai, Fei

    2016-07-01

    The objectives of this study were to investigate the safety and biomechanical stability of a polymethylmethacrylate (PMMA)-augmented bone cement-injectable cannulated pedicle screw (CICPS) in cancellous bone model, and to analyze the stress distribution at the screw-cement-bone interface. The OMEGA cannulated pedicle screw (OPS) and conventional pedicle screw (CPS) were used as control groups. Safety of the CICPS was evaluated by the static bending and bending fatigue tests. Biomechanical stability was analyzed by the maximum axial pullout strength and maximum torque tests. Stress distribution at the screw-cement-bone interface was analyzed by the finite element (FE) method. The CICPS and CPS produced statistically similar values for bending stiffness, bending structural stiffness, and bending yield moment. The maximum pullout force was 53.47 ± 8.65 N in CPS group, compared to 130.82 ± 7.32 N and 175.45 ± 43.01 N in the PMMA-augmented OPS and CICPS groups, respectively (p screw-cement-bone interface in the CICPS group. In conclusion, PMMA-augmentation with CICPS may be a potentially useful method to increase the stability of pedicle screws in patients with osteoporosis. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 960-967, 2016. PMID:25976272

  8. Impact of Different Screw Designs on Durability of Fracture Fixation: In Vitro Study with Cyclic Loading of Scaphoid Bones

    Science.gov (United States)

    Gruszka, Dominik; Herr, Robert; Hely, Hans; Hofmann, Peer; Klitscher, Daniela; Hofmann, Alexander; Rommens, Pol Maria

    2016-01-01

    Purpose The use of new headless compression screws (HCSs) for scaphoid fixation is growing, but the nonunion rate has remained constant. The aim of this study was to compare the stability of fixation resulting from four modern HCSs using a simulated fracture model to determine the optimal screw design(s). Methods We tested 40 fresh-frozen cadaver scaphoids treated with the Acumed Acutrak 2 mini (AA), the KLS Martin HBS2 midi (MH), the Stryker TwinFix (ST) and the Synthes HCS 3.0 with a long thread (SH). The bones with simulated fractures and implanted screws were loaded uniaxially into flexion for 2000 cycles with a constant bending moment of 800 Nmm. The angulation of the fracture fragments was measured continuously. Data were assessed statistically using the univariate ANOVA test and linear regression analysis, and the significance level was set at p < 0.05. Results The median angulation of bone fragments φ allowed by each screw was 0.89° for AA, 1.12° for ST, 1.44° for SH and 2.36° for MH. With regards to linear regression, the most reliable curve was achieved by MH, with a coefficient of determination of R2 = 0.827. This was followed by AA (R2 = 0.354), SH (R2 = 0.247) and ST (R2 = 0.019). Data assessed using an adapted ANOVA model showed no statistically significant difference (p = 0.291) between the screws. Conclusions The continuous development of HCSs has resulted in very comparable implants, and thus, at this time, other factors, such as surgeons’ experience, ease of handling and price, should be taken into consideration. PMID:26741807

  9. Impact of Different Screw Designs on Durability of Fracture Fixation: In Vitro Study with Cyclic Loading of Scaphoid Bones.

    Directory of Open Access Journals (Sweden)

    Dominik Gruszka

    Full Text Available The use of new headless compression screws (HCSs for scaphoid fixation is growing, but the nonunion rate has remained constant. The aim of this study was to compare the stability of fixation resulting from four modern HCSs using a simulated fracture model to determine the optimal screw design(s.We tested 40 fresh-frozen cadaver scaphoids treated with the Acumed Acutrak 2 mini (AA, the KLS Martin HBS2 midi (MH, the Stryker TwinFix (ST and the Synthes HCS 3.0 with a long thread (SH. The bones with simulated fractures and implanted screws were loaded uniaxially into flexion for 2000 cycles with a constant bending moment of 800 Nmm. The angulation of the fracture fragments was measured continuously. Data were assessed statistically using the univariate ANOVA test and linear regression analysis, and the significance level was set at p < 0.05.The median angulation of bone fragments φ allowed by each screw was 0.89° for AA, 1.12° for ST, 1.44° for SH and 2.36° for MH. With regards to linear regression, the most reliable curve was achieved by MH, with a coefficient of determination of R2 = 0.827. This was followed by AA (R2 = 0.354, SH (R2 = 0.247 and ST (R2 = 0.019. Data assessed using an adapted ANOVA model showed no statistically significant difference (p = 0.291 between the screws.The continuous development of HCSs has resulted in very comparable implants, and thus, at this time, other factors, such as surgeons' experience, ease of handling and price, should be taken into consideration.

  10. Histomorphometric evaluation of bone healing in rabbit fibular osteotomy model without fixation

    OpenAIRE

    Paixão Fabio B; Araújo Francisco P; Matos Marcos A

    2008-01-01

    Abstract Background Animal models of fracture consolidation are fundamental for the understanding of the biological process of bone repair in humans, but histological studies are rare and provide only qualitative results. The objective of this article is to present the histomorphometric study of the bone healing process using an experimental model of osteotomy in rabbit fibula without interference of synthesis material. Methods Fifteen rabbits were submitted to fibular osteotomy without any f...

  11. Biodegradable chitin conduit tubulation combined with bone marrow mesenchymal stem cell transplantation for treatment of spinal cord injury by reducing glial scar and cavity formation

    OpenAIRE

    Feng Xue; Er-jun Wu; Pei-xun Zhang; Li-ya A; Yu-hui Kou; Xiao-feng Yin; Na Han

    2015-01-01

    We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive fo...

  12. Bone formation in vivo induced by Cbfa1-carrying adenoviral vectors released from a biodegradable porous {beta}-tricalcium phosphate ({beta}-TCP) material

    Energy Technology Data Exchange (ETDEWEB)

    Uemura, Toshimasa; Kojima, Hiroko, E-mail: t.uemura@aist.go.jp [Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba Central-4, Tsukuba, Ibaraki 305-8562 (Japan)

    2011-06-15

    Overexpression of Cbfa1 (a transcription factor indispensable for osteoblastic differentiation) is expected to induce the formation of bone directly and indirectly in vivo by accelerating osteoblastic differentiation. Adenoviral vectors carrying the cDNA of Cbfa1/til-1(Adv-Cbf1) were allowed to be adsorbed onto porous blocks of {beta}-tricalcium phosphate ({beta}-TCP), a biodegradable ceramic, which were then implanted subcutaneously and orthotopically into bone defects. The adenoviral vectors were released sustainingly by biodegradation, providing long-term expression of the genes. Results of the subcutaneous implantation of Adv-Cbfa1-adsorbed {beta}-TCP/osteoprogenitor cells suggest that a larger amount of bone formed in the pores of the implant than in the control material. Regarding orthotopic implantation into bone defects, the released Adv-Cbfa1 accelerated regeneration in the cortical bone, whereas it induced bone resorption in the marrow cavity. A safer gene transfer using a smaller amount of the vector was achieved using biodegradable porous {beta}-TCP as a carrier.

  13. Biodegradation and cytotoxicity of ciprofloxacin-loaded hydroxyapatite-polycaprolactone nanocomposite film for sustainable bone implants

    OpenAIRE

    Nithya R; Meenakshi Sundaram N

    2015-01-01

    Rajendran Nithya, Nachiappan Meenakshi Sundaram Department of Biomedical Engineering, PSG College of Technology, Coimbatore, India Introduction: In recent years there has been a steep increase in the number of orthopedic patients for many reasons. One major reason is osteomyelitis, caused by pyrogenic bacteria, with progressive infection of the bone or bone marrow and surrounding tissues. So antibiotics must be introduced during bone implantation to avoid prolonged infection.Aim: The object...

  14. Increased Release Time of Antibiotics from Bone Allografts through a Novel Biodegradable Coating

    OpenAIRE

    2014-01-01

    The use of bone allografts is contraindicated in septic revision surgery due to the high risk of graft reinfection. Antibiotic release from the graft may solve the problem and these combinations can theoretically be used for prevention or even therapy of infection. The present study investigated whether amoxicillin, ciprofloxacin, and vancomycin alone or in combination with chitosan or alginate are suitable for short-term or long-term bone coating. Human bone allografts were prepared from fem...

  15. Coating of biodegradable magnesium alloy bone implants using nanostructured diopside (CaMgSi2O6)

    International Nuclear Information System (INIS)

    Magnesium alloys with their biodegradable characteristic can be a very good candidate to be used in orthopedic implants. However, magnesium alloys may corrode and degrade too fast for applications in the bone healing procedure. In order to enhance the corrosion resistance and the in vitro bioactivity of a magnesium alloy, a nanostructured diopside (CaMgSi2O6) film was coated on AZ91 magnesium alloy through combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) methods. The crystalline structures, morphologies and compositions of the coated and uncoated substrates were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy. Polarization, electrochemical impedance spectroscopy, and immersion test in simulated body fluid (SBF) were employed to evaluate the corrosion resistance and the in vitro bioactivity of the samples. The results of our investigation showed that the nanostructured diopside coating deposited on the MAO layer increases the corrosion resistance and improves the in vitro bioactivity of the biodegradable magnesium alloy.

  16. Coating of biodegradable magnesium alloy bone implants using nanostructured diopside (CaMgSi{sub 2}O{sub 6})

    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); Department of Anatomical Sciences and Molecular Biology, School of Medicine, 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); Beni, Batoul Hashemi [Department of Anatomical Sciences and Molecular Biology, School of Medicine, 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); Vashaee, Daryoosh [School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); and others

    2014-01-01

    Magnesium alloys with their biodegradable characteristic can be a very good candidate to be used in orthopedic implants. However, magnesium alloys may corrode and degrade too fast for applications in the bone healing procedure. In order to enhance the corrosion resistance and the in vitro bioactivity of a magnesium alloy, a nanostructured diopside (CaMgSi{sub 2}O{sub 6}) film was coated on AZ91 magnesium alloy through combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) methods. The crystalline structures, morphologies and compositions of the coated and uncoated substrates were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy. Polarization, electrochemical impedance spectroscopy, and immersion test in simulated body fluid (SBF) were employed to evaluate the corrosion resistance and the in vitro bioactivity of the samples. The results of our investigation showed that the nanostructured diopside coating deposited on the MAO layer increases the corrosion resistance and improves the in vitro bioactivity of the biodegradable magnesium alloy.

  17. Coating of biodegradable magnesium alloy bone implants using nanostructured diopside (CaMgSi2O6)

    Science.gov (United States)

    Razavi, Mehdi; Fathi, Mohammadhossein; Savabi, Omid; Beni, Batoul Hashemi; Razavi, Seyed Mohammad; Vashaee, Daryoosh; Tayebi, Lobat

    2014-01-01

    Magnesium alloys with their biodegradable characteristic can be a very good candidate to be used in orthopedic implants. However, magnesium alloys may corrode and degrade too fast for applications in the bone healing procedure. In order to enhance the corrosion resistance and the in vitro bioactivity of a magnesium alloy, a nanostructured diopside (CaMgSi2O6) film was coated on AZ91 magnesium alloy through combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) methods. The crystalline structures, morphologies and compositions of the coated and uncoated substrates were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy. Polarization, electrochemical impedance spectroscopy, and immersion test in simulated body fluid (SBF) were employed to evaluate the corrosion resistance and the in vitro bioactivity of the samples. The results of our investigation showed that the nanostructured diopside coating deposited on the MAO layer increases the corrosion resistance and improves the in vitro bioactivity of the biodegradable magnesium alloy.

  18. Biodegradable polymers: emerging excipients for the pharmaceutical and medical device industries.

    Directory of Open Access Journals (Sweden)

    Bhavesh Patel

    2013-12-01

    Full Text Available Worldwide many researchers are exploring the potential use of biodegradable polymerics as carriers for a wide range of therapeutic applications. In the past two decades, considerable progress has been made in the development of biodegradable polymeric materials, mainly in the biomedical and pharmaceutical industries due to their versatility, biocompatibility and biodegradability properties. The present review focuses on the use of biodegradable polymers in various therapeutic areas like orthopedic and contraceptive device, surgical sutures, implants, depot parenteral injections, etc. Biodegradable polymers have also contributed significantly to the development of drug-eluting stents (DES used for the treatment of obstructive coronary artery disease, such as angioplasty. Biodegradable synthetic polymers have potential applications in orthopedic device fixation due to properties that impact bone healing, formation, regeneration or substitution in the human body. The present review also emphasizes areas such as the chemistry of polymer synthesis, factors affecting the biodegradation, methods for the production of biodegradable polymer based formulations, the application of biodegradable polymers in dental implants, nasal drug deliveries, contraceptive devices, immunology, gene, transdermal, ophthalmic and veterinary applications, as well as, the sterilization of biodegradable based formulations and regulatory considerations for product filing.

  19. Biocompatibility and biodegradation studies of PCL/β-TCP bone tissue scaffold fabricated by structural porogen method.

    Science.gov (United States)

    Lu, Lin; Zhang, Qingwei; Wootton, David; Chiou, Richard; Li, Dichen; Lu, Bingheng; Lelkes, Peter; Zhou, Jack

    2012-09-01

    Three-dimensional printer (3DP) (Z-Corp) is a solid freeform fabrication system capable of generating sub-millimeter physical features required for tissue engineering scaffolds. By using plaster composite materials, 3DP can fabricate a universal porogen which can be injected with a wide range of high melting temperature biomaterials. Here we report results toward the manufacture of either pure polycaprolactone (PCL) or homogeneous composites of 90/10 or 80/20 (w/w) PCL/beta-tricalcium phosphate (β-TCP) by injection molding into plaster composite porogens fabricated by 3DP. The resolution of printed plaster porogens and produced scaffolds was studied by scanning electron microscopy. Cytotoxicity test on scaffold extracts and biocompatibility test on the scaffolds as a matrix supporting murine osteoblast (7F2) and endothelial hybridoma (EAhy 926) cells growth for up to 4 days showed that the porogens removal process had only negligible effects on cell proliferation. The biodegradation tests of pure PCL and PCL/β-TCP composites were performed in DMEM with 10 % (v/v) FBS for up to 6 weeks. The PCL/β-TCP composites show faster degradation rate than that of pure PCL due to the addition of β-TCP, and the strength of 80/20 PCL/β-TCP composite is still suitable for human cancellous bone healing support after 6 weeks degradation. Combining precisely controlled porogen fabrication structure, good biocompatibility, and suitable mechanical properties after biodegradation, PCL/β-TCP scaffolds fabricated by 3DP porogen method provide essential capability for bone tissue engineering. PMID:22669285

  20. Magnetic biodegradable Fe{sub 3}O{sub 4}/CS/PVA nanofibrous membranes for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Wei Yan; Zhang Xuehui; Hu Xiaoyang; Deng Xuliang [Department of Geriatric Dentistry, School and Hospital of Stomatology, Peking University, Beijing, 100081 (China); Song Yu; Lin Yuanhua [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing, 100084 (China); Han Bing [Department of Orthodontics, School and Hospital of Stomatology, Peking University, Beijing, 100081 (China); Wang Xinzhi, E-mail: kqdengxuliang@bjmu.edu.cn [Department of Prosthodontics, School and Hospital of Stomatology, Peking University, Beijing, 100081 (China)

    2011-10-15

    In recent years, interest in magnetic biomimetic scaffolds for tissue engineering has increased considerably. The aim of this study is to develop magnetic biodegradable fibrous materials with potential use in bone regeneration. Magnetic biodegradable Fe{sub 3}O{sub 4}/chitosan (CS)/poly vinyl alcohol (PVA) nanofibrous membranes were achieved by electrospinning with average fiber diameters ranging from 230 to 380 nm and porosity of 83.9-85.1%. The influences of polymer concentration, applied voltage and Fe{sub 3}O{sub 4} nanoparticles loading on the fabrication of nanofibers were investigated. The polymer concentration of 4.5 wt%, applied voltage of 20 kV and Fe{sub 3}O{sub 4} nanoparticles loading of lower than 5 wt% could produce homogeneous, smooth and continuous Fe{sub 3}O{sub 4}/CS/PVA nanofibrous membranes. X-ray diffraction (XRD) data confirmed that the crystalline structure of the Fe{sub 3}O{sub 4}, CS and PVA were maintained during electrospinning process. Fourier transform infrared spectroscopy (FT-IR) demonstrated that the Fe{sub 3}O{sub 4} loading up to 5 wt% did not change the functional groups of CS/PVA greatly. Transmission electron microscopy (TEM) showed islets of Fe{sub 3}O{sub 4} nanoparticles evenly distributed in the fibers. Weak ferrimagnetic behaviors of membranes were revealed by vibrating sample magnetometer (VSM) test. Tensile test exhibited Young's modulus of membranes that were gradually enhanced with the increase of Fe{sub 3}O{sub 4} nanoparticles loading, while ultimate tensile stress and ultimate strain were slightly reduced by Fe{sub 3}O{sub 4} nanoparticles loading of 5%. Additionally, MG63 human osteoblast-like cells were seeded on the magnetic nanofibrous membranes to evaluate their bone biocompatibility. Cell growth dynamics according to MTT assay and scanning electron microscopy (SEM) observation exhibited good cell adhesion and proliferation, suggesting that this magnetic biodegradable Fe{sub 3}O{sub 4}/CS/PVA nanofibrous

  1. Silicon, iron and titanium doped calcium phosphate-based glass reinforced biodegradable polyester composites as bone analogous materials

    Science.gov (United States)

    Shah Mohammadi, Maziar

    Bone defects resulting from disease or traumatic injury is a major health care problem worldwide. Tissue engineering offers an alternative approach to repair and regenerate bone through the use of a cell-scaffold construct. The scaffold should be biodegradable, biocompatible, porous with an open pore structure, and should be able to withstand the applied forces. Phosphate-based glasses (PGs) may be used as reinforcing agents in degradable composites since their degradation can be predicted and controlled through their chemistry. This doctoral dissertation describes the development and evaluation of PGs reinforced biodegradable polyesters for intended applications in bone augmentation and regeneration. This research was divided into three main objectives: 1) Investigating the composition dependent properties of novel PG formulations by doping a sodium-free calcium phosphate-based glass with SiO2, Fe2O3, and TiO2. Accordingly, (50P2 O5-40CaO- xSiO2-(10-x)Fe2O3, where x = 10, 5 and 0 mol.%) and (50P2O5-40CaO-xSiO 2-(10-x)TiO2 where x = 10, 7, 5, 3 and 0 mol.%) formulations were developed and characterised. SiO2 incorporation led to increased solubility, ion release, pH reduction, as well as hydrophilicity, surface energy, and surface polarity. In contrast, doping with Fe2O 3 or TiO2 resulted in more durable glasses, and improved cell attachment and viability. It was hypothesised that the presence of SiO 2 in the TiO2-doped formulations could up-regulate the ionic release from the PG leading to higher alkaline phosphatase activity of MC3T3-E1 cells. 2) Incorporating Si, Fe, and Ti doped PGs as fillers, either as particulates (PGPs) or fibres (PGFs), into biodegradable polyesters (polycaprolactone (PCL) and semi-crystalline and amorphous poly(lactic acid) (PLA and PDLLA)) with the aim of developing degradable bone analogous composites. It was found that PG composition and geometry dictated the weight loss, ionic release, and mechanical properties of the composites. It

  2. Analysis of elements in the soft tissue covering titanium plates and screws for internal bone fixation by the PIXE method

    International Nuclear Information System (INIS)

    We made a comparative study of the elements in the periosteum on titanium plates and screws for internal bone fixation, normal periosteum, and oral mucosa by the PIXE method. We studied 11 patients, 4 men and 7 women, with mandibular fracture or facial deformity. The implanted time length of the materials in the body was 5 to 16 months. The analyzed samples were 11 periostea on the materials, 11 normal periostea and 4 oral mucosae. The results were as follows. Twenty- four essential and 11 contaminated elements were detected in the periostea on the materials as well as in the normal periostea and the oral mucosae. In the mean values of titanium and aluminum, there were significantly higher values in the periostea on the materials than in the normal periostea. The mean concentration values of the other elements did not differ significantly between that in the periostea on the materials and that in the normal periostea. The concentration of titanium in the periostea on the materials was not correlated with sex, age of the patients, or the implanted time length. However, there was a significantly higher titanium concentration value in tile periostea on the plates than on the screws. Our results could indicate that the existence of a titanium element in the periostea on the materials was caused by its dissolution from the materials. (author)

  3. Manufacturing of individual biodegradable bone substitute implants using selective laser melting technique.

    Science.gov (United States)

    Lindner, Markus; Hoeges, Simon; Meiners, Wilhelm; Wissenbach, Konrad; Smeets, Ralf; Telle, Rainer; Poprawe, Reinhart; Fischer, Horst

    2011-06-15

    The additive manufacturing technique selective laser melting (SLM) has been successfully proved to be suitable for applications in implant manufacturing. SLM is well known for metal parts and offers direct manufacturing of three-dimensional (3D) parts with high bulk density on the base of individual 3D data, including computer tomography models of anatomical structures. Furthermore, an interconnecting porous structure with defined and reproducible pore size can be integrated during the design of the 3D virtual model of the implant. The objective of this study was to develop the SLM processes for a biodegradable composite material made of β-tricalcium phosphate (β-TCP) and poly(D, L)-lactide (PDLLA). The development of a powder composite material (β-TCP/PDLLA) suitable for the SLM process was successfully performed. The microstructure of the manufactured samples exhibit a homogeneous arrangement of ceramic and polymer. The four-point bending strength was up to 23 MPa. The X-ray diffraction (XRD) analysis of the samples confirmed β-TCP as the only present crystalline phase and the gel permeations chromatography (GPC) analysis documented a degradation of the polymer caused by the laser process less than conventional manufacturing processes. We conclude that SLM presents a new possibility to manufacture individual biodegradable implants made of β-TCP/PDLLA. PMID:21495168

  4. Use of stereolithography to manufacture critical-sized 3D biodegradable scaffolds for bone ingrowth.

    Science.gov (United States)

    Cooke, Malcolm N; Fisher, John P; Dean, David; Rimnac, Clare; Mikos, Antonios G

    2003-02-15

    A novel approach to the manufacture of biodegradable polymeric scaffolds for tissue-engineering utilizing stereolithography (SLA) is presented. SLA is a three-dimensional (3D) printing method that uses an ultraviolet laser to photo-crosslink a liquid polymer substrate. The current generation of SLA devices provide a 3D printing resolution of 0.1 mm. The experiments utilized a biodegradable resin mixture of diethyl fumarate (DEF), poly(propylene fumarate) (PPF), and a photoinitiator, bisacylphosphine oxide (BAPO). The PPF is crosslinked with the use of the SLA's UV laser (325-nm wavelength). An SLA device was retrofitted with a custom fixture build tank enclosing an elevator-driven build table. A 3D prototype model testing the manufacturing control this device provides was created in a computer-aided-design package. The resulting geometric data were used to drive the SLA process, and a DEF/PPF prototype part was successfully manufactured. These scaffolds have application in the tissue engineering of bony substrates. PMID:12516080

  5. Adhesive B-doped DLC films on biomedical alloys used for bone fixation

    Indian Academy of Sciences (India)

    A A Ahmad; A M Alsaad

    2007-08-01

    The long-term failure of the total hip and knee prostheses is attributed to the production of wear particles at the articulating interface between the metals, ceramics and polymers used for surgical implants and bone-fixtures. Therefore, finding an adhesive and inert coating material that has low frictional coefficient should dramatically reduce the production of wear particles and hence, prolong the life time of the surgical implants. The novel properties of the non-toxic diamond-like carbon (DLC) coatings have proven to be excellent candidates for biomedical applications. However, they have poor adhesion strength to the alloys and biomaterials. The addition of a thin interfacial layer such as Si, Ti, TiN, Mo and Cu/Cr and/or adding additives such as Si, F, N, O, W, V, Co, Mo, Ti or their combinations to the DLC films has been found to increase the adhesion strength substantially. In our study, grade 316L stainless steel and grade 5 titanium alloy (Ti–6Al–4V) were used as biomaterial substrates. They were coated with DLC films containing boron additives at various levels using various Si interfacial layer thicknesses. The best film adhesion was achieved at 8% and 20% on DLC coated Ti–6Al–4V and grade 316L substrates, respectively. It has been demonstrated that doping the DLC with boron increases their adhesion strength to both substrates even without silicon interfacial layer and increases it substantially with optimum silicon layer thickness. The adhesion strength is also correlated with the hydrogen contents in the B-DLC films. It is found to reach its maximum value of 700 kg/cm2 and 390 kg/cm2 at 2/7 and 3/6 for CH4/Ar partial pressures (in mTorr ratio) for Ti–6Al–4V and 316L substrates, respectively.

  6. BOHLER'S ANGLE: CORRELATION WITH OUTCOME IN DISPLACED INTRA-ARTICULAR CALCANEAL FRACTURES TREATED WITH LOCKING COMPRESSION PLATE FIXATION WITH AND WITHOUT BONE GRAFTING

    Directory of Open Access Journals (Sweden)

    Deepak P

    2014-09-01

    Full Text Available BOHLER'S ANGLE: correlation with outcome in displaced intra-articular calcaneal fractures Treated with locking compression Plate Fixation with and without bone grafting. AIMS: The aim is an accurate reduction of the fracture with reconstruction of Bohler’s angle, length and axis and sub talar joint surface. To determine whether autologous bone graft supplementation is beneficial in achieving and maintaining restoration of Calcaneal height and anatomic reduction. SETTINGS AND DESIGN: Level 1 trauma center, Prospective, randomized. METHODS AND MATERIAL: Consecutive 46 patients who had fracture calcaneum were treated by open reduction and internal fixation by locking plate with and without bone graft during the period from November 2009 to April 2012. STATISTICAL ANALYSIS USED: AOFAS-Ankle-Hind foot Scale, t Test. RESULTS: Fewer complications and statistically significant better results related to treatment with locking plates with bone grafting confirmed in comparison to without bone grafting ones were noted for intra-articular calcaneal fractures. In Group A the mean time for union was 10.39wks. The results were good and excellent in 86.95%, 8.69 % had fair result and 4.34% had poor results. In Group B the mean time for union was 11.95 wks. The overall results were good and excellent in 73.91%, 13.04 % had fair result and 13.04 % had poor results. CONCLUSIONS: The operative treatment of intra-articular calcaneal fractures could restore Böhler's angle better and the patient could return to full weight bearing earlier. We confirmed that autologous bone graft supplementation is beneficial in achieving and maintaining restoration of calcaneal height and anatomic reduction.

  7. Rehabilitation instruction after intervertebral bone graft internal fixation of lumbar spondylolisthesis%腰椎滑脱椎体间植骨固定术后的康复指导

    Institute of Scientific and Technical Information of China (English)

    张晋亭

    2003-01-01

    @@ BACKGROUND:Internal fixation of lumbral spondylolisthesis has resolved the problem caused by vertebral translocation and postoperative rehabilitation instruction can prevent moving of bone.Directed to different stages,suitable posture and rehabilitation function exercises can effectively prevent loose intervertebral grafted bone and adhesion of nerve root.

  8. Biodegradable chitin conduit tubulation combined with bone marrow mesenchymal stem cell transplantation for treatment of spinal cord injury by reducing glial scar and cavity formation

    Directory of Open Access Journals (Sweden)

    Feng Xue

    2015-01-01

    Full Text Available We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive for S100 (Schwann cell marker and glial fibrillary acidic protein (glial cell marker at 8 weeks. Retrograde tracing showed that more nerve fibers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our findings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvironment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.

  9. Biodegradable chitin conduit tubulation combined with bone marrow mesenchymal stem cell transplantation for treatment of spinal cord injury by reducing glial scar and cavity formation

    Institute of Scientific and Technical Information of China (English)

    Feng Xue; Er-jun Wu; Pei-xun Zhang; Li-ya A; Yu-hui Kou; Xiao-feng Yin; Na Han

    2015-01-01

    We examined the restorative effect of modiifed biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantationin vivo, and differentiated into cells double-positive for S100 (Schwann cell marker) and glial ifbrillary acidic protein (glial cell marker) at 8 weeks. Retrograde tracing showed that more nerve ifbers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our ifndings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvi-ronment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.

  10. Surface modification of biodegradable porous Mg bone scaffold using polycaprolactone/bioactive glass composite.

    Science.gov (United States)

    Yazdimamaghani, Mostafa; Razavi, Mehdi; Vashaee, Daryoosh; Tayebi, Lobat

    2015-04-01

    A reduction in the degradation rate of magnesium (Mg) and its alloys is in high demand to enable these materials to be used in orthopedic applications. For this purpose, in this paper, a biocompatible polymeric layer reinforced with a bioactive ceramic made of polycaprolactone (PCL) and bioactive glass (BG) was applied on the surface of Mg scaffolds using dip-coating technique under low vacuum. The results indicated that the PCL-BG coated Mg scaffolds exhibited noticeably enhanced bioactivity compared to the uncoated scaffold. Moreover, the mechanical integrity of the Mg scaffolds was improved using the PCL-BG coating on the surface. The stable barrier property of the coatings effectively delayed the degradation activity of Mg scaffold substrates. Moreover, the coatings induced the formation of apatite layer on their surface after immersion in the SBF, which can enhance the biological bone in-growth and block the microcracks and pore channels in the coatings, thus prolonging their protective effect. Furthermore, it was shown that a three times increase in the concentration of PCL-BG noticeably improved the characteristics of scaffolds including their degradation resistance and mechanical stability. Since bioactivity, degradation resistance and mechanical integrity of a bone substitute are the key factors for repairing and healing fractured bones, we suggest that PCL-BG is a suitable coating material for surface modification of Mg scaffolds. PMID:25686970

  11. Percutaneous reduction and fixation of an intra-articular calcaneal fracture using an inflatable bone tamp: description of a novel and safe technique

    Directory of Open Access Journals (Sweden)

    Mauffrey Cyril

    2012-03-01

    Full Text Available Abstract Calcaneal fractures are common injuries involving the hind foot and often a source of significant long-term morbidity. Treatment options have changed throughout the ages from periods of preferred nonoperative management to closed reduction with a mallet, and more recently, open reduction and anatomic internal fixation. The current treatment of choice; however, is often debated, as open management of these fractures carries many risks to include wound breakdown and infection. A less invasive form of surgical management through small incisions, while maintaining the ability to obtain joint congruency, anatomic alignment, and restore calcaneal height and width would be ideal. We propose a novel form of fracture reduction using an inflatable bone tamp and percutaneous fracture fixation. Preoperative planning and experienced fluoroscopy is crucial to successful management using this method. Although we achieved successful radiographic outcome in this case, long-term functional outcome of this technique are yet to be published.

  12. The use of postoperative irradiation for the prevention of heterotopic bone after total hip replacement with biologic fixation (porous coated) prosthesis: An animal model

    International Nuclear Information System (INIS)

    Radiation has been shown to be effective in the prevention of heterotopic bone. The exact etiology of heterotopic bone is unknown. Total hip prosthetic devices that do not depend upon bone cement for fixation have become increasingly popular. The mechanism by which the bone forms around the prosthesis is similar to the process by which fractures heal which has been shown to be sensitive to irradiation. Using a rabbit model we have undertaken a study to investigate the effect of irradiation on the bony ingrowth on porous coated implants. Forty-five rabbits had porous coated implants surgically placed in the tibiae bilaterally. Each rabbit had one tibia randomly irradiated with 1,000 cGy in 5 fractions starting on the first post-operative day. Animals were sacrificed weekly starting 2 weeks post-operatively and the tibae were sent for pullout studies. The amount of force necessary to pullout the treated tibae was statistically less than the amount of force necessary to remove the untreated tibae at 2 weeks. From 3 weeks on there was no difference in the force necessary to remove the prosthesis from the untreated or treated tibae. Histologically, the untreated tibae showed bone formation while the treated tibae did not. Because of these results, it is suggested that the treatment of patients at risk for development of heterotopic bone be modified to only include the area between the femur and pelvis avoiding treatment of the prosthetic device

  13. Bone-repair properties of biodegradable hydroxyapatite nano-rod superstructures

    Science.gov (United States)

    D'Elía, Noelia L.; Mathieu, Colleen; Hoemann, Caroline D.; Laiuppa, Juan A.; Santillán, Graciela E.; Messina, Paula V.

    2015-11-01

    Nano-hydroxyapatite (nano-HAp) materials show an analogous chemical composition to the biogenic mineral components of calcified tissues and depending on their topography they may mimic the specific arrangement of the crystals in bone. In this work, we have evaluated the potential of four synthesized nano-HAp superstructures for the in vitro conditions of bone-repair. Experiments are underway to investigate the effects of the material microstructure, surface roughness and hydrophilicity on their osseo-integration, osteo-conduction and osteo-induction abilities. Materials were tested in the presence of both, rat primary osteoblasts and rabbit mesenchymal stem cells. The following aspects are discussed: (i) cytotoxicity and material degradation; (ii) rat osteoblast spreading, proliferation and differentiation; and (iii) rabbit mesenchymal stem cell adhesion on nano-HAp and nano-HAp/collagen type I coatings. We effectively prepared a material based on biomimetic HAp nano-rods displaying the appropriate surface topography, hydrophilicity and degradation properties to induce the in vitro desired cellular responses for bone bonding and healing. Cells seeded on the selected material readily attached, proliferated and differentiated, as confirmed by cell viability, mitochondrial metabolic activity, alkaline phosphatase (ALP) activity and cytoskeletal integrity analysis by immunofluorescence localization of alpha-smooth muscle actin (α-SMA) protein. These results highlight the influence of material's surface characteristics to determine their tissue regeneration potential and their future use in engineering osteogenic scaffolds for orthopedic implants.Nano-hydroxyapatite (nano-HAp) materials show an analogous chemical composition to the biogenic mineral components of calcified tissues and depending on their topography they may mimic the specific arrangement of the crystals in bone. In this work, we have evaluated the potential of four synthesized nano-HAp superstructures

  14. PGA-incorporated collagen: Toward a biodegradable composite scaffold for bone-tissue engineering.

    Science.gov (United States)

    Toosi, Shirin; Naderi-Meshkin, Hojjat; Kalalinia, Fatemeh; Peivandi, Mohammad Taghi; HosseinKhani, Hossein; Bahrami, Ahmad Reza; Heirani-Tabasi, Asieh; Mirahmadi, Mahdi; Behravan, Javad

    2016-08-01

    Nowadays composite scaffolds based on synthetic and natural biomaterials have got attention to increase healing of non-union bone fractures. To this end, different aspects of collagen sponge incorporated with poly(glycolic acid) (PGA) fiber were investigated in this study. Collagen solution (6.33 mg/mL) with PGA fibers (collagen/fiber ratio [w/w]: 4.22, 2.11, 1.06, 0.52) was freeze-dried, followed by dehydrothermal cross-linking to obtain collagen sponge incorporating PGA fibers. Properties of scaffold for cell viability, proliferation, and differentiation of mesenchymal stem cells (MSCs) were evaluated. Scanning electron microscopy showed that collagen sponge exhibited an interconnected pore structure with an average pore size of 190 μm, irrespective of PGA fiber incorporation. The collagen-PGA sponge was superior to the original collagen sponge in terms of the initial attachment, proliferation rate, and osteogenic differentiation of the bone marrow-MSCs (BM-MSC). The shrinkage of sponges during cell culture was significantly suppressed by fiber incorporation. Incorporation of PGA fiber is a simple and promising way to reinforce collagen sponge without impairing biocompatibility. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2020-2028, 2016. PMID:27059133

  15. Investigation of mechanism of bone regeneration in a porous biodegradable calcium phosphate (CaP) scaffold by a combination of a multi-scale agent-based model and experimental optimization/validation

    Science.gov (United States)

    Zhang, Le; Qiao, Minna; Gao, Hongjie; Hu, Bin; Tan, Hua; Zhou, Xiaobo; Li, Chang Ming

    2016-08-01

    Herein, we have developed a novel approach to investigate the mechanism of bone regeneration in a porous biodegradable calcium phosphate (CaP) scaffold by a combination of a multi-scale agent-based model, experimental optimization of key parameters and experimental data validation of the predictive power of the model. The advantages of this study are that the impact of mechanical stimulation on bone regeneration in a porous biodegradable CaP scaffold is considered, experimental design is used to investigate the optimal combination of growth factors loaded on the porous biodegradable CaP scaffold to promote bone regeneration and the training, testing and analysis of the model are carried out by using experimental data, a data-mining algorithm and related sensitivity analysis. The results reveal that mechanical stimulation has a great impact on bone regeneration in a porous biodegradable CaP scaffold and the optimal combination of growth factors that are encapsulated in nanospheres and loaded into porous biodegradable CaP scaffolds layer-by-layer can effectively promote bone regeneration. Furthermore, the model is robust and able to predict the development of bone regeneration under specified conditions.

  16. Dual delivery of active antibactericidal agents and bone morphogenetic protein at sustainable high concentrations using biodegradable sheath-core-structured drug-eluting nanofibers.

    Science.gov (United States)

    Hsu, Yung-Hen; Lin, Chang-Tun; Yu, Yi-Hsun; Chou, Ying-Chao; Liu, Shih-Jung; Chan, Err-Cheng

    2016-01-01

    In this study, we developed biodegradable sheath-core-structured drug-eluting nanofibers for sustainable delivery of antibiotics (vancomycin and ceftazidime) and recombinant human bone morphogenetic protein (rhBMP-2) via electrospinning. To prepare the biodegradable sheath-core nanofibers, we first prepared solutions of poly(d,l)-lactide-co-glycolide, vancomycin, and ceftazidime in 1,1,1,3,3,3-hexafluoro-2-propanol and rhBMP-2 in phosphate-buffered solution. The poly(d,l)-lactide-co-glycolide/antibiotics and rhBMP-2 solutions were then fed into two different capillary tubes controlled by two independent pumps for coaxial electrospinning. The electrospun nanofiber morphology was observed under a scanning electron microscope. We further characterized the in vitro antibiotic release from the nanofibers via high-performance liquid chromatography and that of rhBMP-2 via enzyme-linked immunosorbent assay and alkaline phosphatase activity. We showed that the biodegradable coaxially electrospun nanofibers could release high vancomycin/ceftazidime concentrations (well above the minimum inhibition concentration [MIC]90) and rhBMP-2 for >4 weeks. These experimental results demonstrate that novel biodegradable nanofibers can be constructed with various pharmaceuticals and proteins for long-term drug deliveries. PMID:27574423

  17. Therapeutic efficacy of pedicle screw-rod internal fixation after one-stage posterior transforaminal lesion debridement and non-structural bone grafting for tuberculosis of lumbar vertebra

    Directory of Open Access Journals (Sweden)

    Jia-ming LIU

    2015-11-01

    Full Text Available Objective To evaluate the efficacy and safety of pedicle screw-rod internal fixation after one-stage posterior transforaminal lesion debridement and non-structural bone grafting in the treatment of tuberculosis of mono-segmental lumbar vertebra. Methods From January 2010 to April 2013, 21 patients (9 males and 12 females with an average age of 49.1 years with mono-segmental tuberculosis of lumbar vertebra underwent surgery in our hospital were included. Eight patients had neurological deficit. The focus of tuberculosis was located on one side of the vertebral body, and all the patients had obvious signs of bone destruction on CT and MRI. All the patients were given anti-tuberculosis chemotherapy for 2-3 weeks before surgery. The local bone chips and autologous iliac cancellous bone were used as the intervertebral bone graft. Postoperative plain radiographs and CT were obtained to evaluate the fusion rate and degree of lumbar lordosis. The visual analogue scale score (VAS, erythrocyte sedimentation rate (ESR, and C-reactive protein (CRP before and after operation, and at final follow-up date were recorded. Results All the patients were followed up for 25.3±4.2 months. The mean operation time was 157±39 minutes, and the average blood loss was 470±143ml. The fusion rate of the interbody bone graft was 95.2%, with an average fusion period of 6.1±2.5 months. The neurological function was improved by 100%, and no severe complication or neurological injury occured. The preoperative and postoperative lordosis angles of the lumbar spine were 21.4°±5.7° and 33.6°±3.1°, respectively, and it was 31.3°±2.7° at the final follow up. The preoperative and postoperative VAS scores were 7.8±2.6 and 2.4±1.7 respectively, and it was 0.9±0.7 at the final follow up. The ESR and CRP were significantly decreased 3 months after surgery, and they became normal at 6 months. Conclusion Pedicle screw-rod internal fixation after one-stage posterior

  18. A comparison of the rates of union after cancellous iliac crest bone graft and Kirschner-wire fixation in the treatment of stable and unstable scaphoid nonunion.

    Science.gov (United States)

    Park, H Y; Yoon, J O; Jeon, I H; Chung, H W; Kim, J S

    2013-06-01

    This study was performed to determine whether pure cancellous bone graft and Kirschner (K-) wire fixation were sufficient to achieve bony union and restore alignment in scaphoid nonunion. A total of 65 patients who underwent cancellous bone graft and K-wire fixation were included in this study. The series included 61 men and four women with a mean age of 34 years (15 to 72) and mean delay to surgery of 28.7 months (3 to 240). The patients were divided into an unstable group (A) and stable group (B) depending on the pre-operative radiographs. Unstable nonunion was defined as a lateral intrascaphoid angle > 45°, or a radiolunate angle > 10°. There were 34 cases in group A and 31 cases in group B. Bony union was achieved in 30 patients (88.2%) in group A, and in 26 (83.9%) in group B (p = 0.439). Comparison of the post-operative radiographs between the two groups showed no significant differences in lateral intrascaphoid angle (p = 0.657) and scaphoid length (p = 0.670) and height (p = 0.193). The radiolunate angle was significantly different (p = 0.020) but the mean value in both groups was scaphoid nonunion. PMID:23723277

  19. 人工骨或自体骨移植联合椎弓根钉内固定修复脊柱结核%Artificial bone or autologous bone grafting combined with pedicle screw fixation for repair of spinal tuberculosis

    Institute of Scientific and Technical Information of China (English)

    姜棚菲; 翟文斌

    2015-01-01

    BACKGROUND:With the development of fixation materials and technology, scholars began to use artificial bone materials combined with pedicle screw fixation in the repair of spinal tuberculosis. OBJECTIVE: To summarize the characteristics of artificial bone materials combined with pedicle screw fixation in the repair of spinal tuberculosis. METHODS:The literatures about artificial bone graft materials in repair of spinal tuberculosis were retrieved from CNKI and PubMed database during 1985 to 2014 by computer. The keywords were “spinal tuberculosis, bone transplantation, internal fixation” in Chinese and English, respectively. RESULTS AND CONCLUSION:In the repair of spinal tuberculosis using artificial bone materials combined with pedicle screw fixation, autologous bone is the gold standard for bone grafting, presenting with no immune rejection. To avoid the occurrence of limited bone mass, pain and other complications, however, artificial bone materials have been extensively studied. Currently used artificial materials mainly include titanium and its aloys, hydroxyapatite composites and medical calcium sulfate, which al have good biocompatibility. But there are stil certain limitations and shortcomings.%背景:随着内固定材料和内固定技术的发展,越来越多的国内外学者开始应用人工骨材料联合椎弓根钉内固定修复脊柱结核。目的:综述人工骨修复材料联合椎弓根内固定修复脊柱结核的特点。方法:应用计算机检索CNKI和PubMed数据库1985至2014年有关人工骨移植材料修复脊椎结核方面的文献,中文关键词为“脊椎结核、骨移植、内固定”,英文关键词为“Spinal tuberculosis,Bone graft,Fixation”。结果与结论:在骨修复材料联合椎弓根内固定修复脊柱结核中,自体骨是骨移植的金标准,无免疫排斥反应,但为了避免自体骨取骨量有限、取骨后疼痛等并发症的发生,人工骨材料得到了广泛

  20. The role of bone SPECT/CT in the evaluation of lumbar spinal fusion with metallic fixation devices

    DEFF Research Database (Denmark)

    Damgaard, Morten; Nimb, Lars; Madsen, Jan L

    2010-01-01

    PURPOSE: It is difficult to evaluate the stability of the lumbar spondylodesis with metallic fixation devices by conventional imaging methods such as radiography or magnetic resonance imaging. It is unknown whether single photon emission computed tomography/computed tomography (SPECT/CT) may be u...

  1. The new concept of the monitoring and appraisal of bone union inflexibility of fractures treated by Dynastab DK external fixator.

    Science.gov (United States)

    Lenz, Gerhard P; Stasiak, Andrzej; Deszczyński, Jarosław; Karpiński, Janusz; Stolarczyk, Artur; Ziółkowski, Marcin; Szczesny, Grzegorz

    2003-10-30

    Background. This work focuses on problems of heuristic techniques based on artificial intelligence. Mainly about artificial non-linear and multilayer neurons, which were used to estimate the bone union fractures treatment process using orthopaedic stabilizers Dynastab DK. Material and methods. The author utilizes computer software based on multilayer neuronal network systems, which allows to predict the curve of the bone union at early stages of therapy. The training of the neural net has been made on fifty six cases of bone fracture which has been cured by the Dynastab stabilizers DK. Using such trained net, seventeen fractures of long bones shafts were being examined on strength and prediction of the bone union as well. Results. Analyzing results, it should be underlined that mechanical properties of the bone union in the slot of fracture are changing in nonlinear way in function of time. Especially, major changes were observed during the forth month of the fracture treatment. There is strong correlation between measure number two and measure number six. Measure number two is more strict and in the matter of fact it refers to flexion, as well as the measure number six, to compression of the bone in the fracture slot. Conclusions. Consequently, deflection loads are especially hazardous for healing bone. The very strong correlation between real curves and predicted curves shows the correctness of the neuronal model. PMID:17679847

  2. Fixation of non-cemented total hip arthroplasty femoral components in a simulated proximal bone defect model.

    Science.gov (United States)

    Sangiorgio, Sophia N; Ebramzadeh, Edward; Knutsen, Ashleen R; Borkowski, Sean L; Kalma, Jeremy J; Bengs, Benjamin C

    2013-10-01

    An accelerated sequential proximal femoral bone loss model was used to measure the initial stability of three noncemented femoral stem designs: fully porous-coated, proximally porous-coated, and dual-tapered, diaphyseal press-fit (N=18). Only dual-tapered, diaphyseal press-fit stems remained stable with as much as 105 mm of bone loss, with average cyclic micromotion remaining below 25 μm in ML and below 10 μm in AP planes. In contrast, with proximally coated and fully coated stem designs with circular or oval cross-sections, 60mm of bone loss, resulting in lower than 10 cm of diaphyseal bone contact length, led to gross instability, increasing average cyclic micromotions to greater than 100 μm prior to failure. Therefore, the results provide support for using a dual-tapered stem in revision cases with proximal bone loss. PMID:23523487

  3. 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)

    Baad-Hansen, Thomas Einer; Overgaard, S; Lind, M;

    2007-01-01

    weeks osteogenic protein-1 increased bone formation and the energy absorption of implants grafted with allograft and ProOsteon. A composite of allograft, ProOsteon and osteogenic protein-1 was comparable, but not superior to, allograft used on its own. ProOsteon alone cannot be recommended as a......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...... 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...

  4. One lesson from arthroplasty to osseointegration in search for better fixation of in-bone implanted prosthesis

    OpenAIRE

    Pitkin, Mark

    2008-01-01

    Direct transcutaneous prosthetic attachment (osseointegration) consists of implanting directly into the residuum bone a metal pylon whose external fraction connects the residuum to the external prosthesis. Since the introduction of osseointegration about 20 years ago, the obvious challenge associated with this technology has been the skin-pylon interface as a source of infections. In comparison, the bone-device interface was considered less problematic because of the knowledge and experience ...

  5. Enhancing Interfacial Bonding of a Biodegradable Calcium Polyphosphate/ Polyvinyl-urethane Carbonate Interpenetrating Phase Composite for Load Bearing Fracture Fixation Applications

    Science.gov (United States)

    Guo, Yi

    This thesis describe methods to improve the interfacial stability of an interpenetrating phase composite (IPC) (comprised of porous calcium polyphosphate and polyvinylurethanecarbonate), and to increase the hydrophobicity of the polymer phase. The current IPCs introduce covalent bonding between the two phases via silanizing agents to enhance the interfacial stability. Incorporation of the silanizing agents was also intended to reduce the IPC's sensitivity to interfacial hydration, thereby further enhancing the IPC's resistance to rapid degradation during aqueous solution aging. Lysine diisocyanate was used to increase the hydrophobic character in the polyvinylurethanecarbonate infiltrating resin. The polymer resins were infiltrated into porous CPP blocks with 25 volume % interconnected porosity and polymerized to produce the IPCs. After mechanical testing following a 28-day aging study it was found that the silanizing agents contributed to long-term stability of the mechanical properties under aqueous conditions. It was concluded that the mechanical properties and long-term stability were comparable to available nonmetallic and biodegradable composites, as well as being biocompatible to a preosteoblast model cell line.

  6. Posterior transodontoid fixation: A new fixation (Kotil technique

    Directory of Open Access Journals (Sweden)

    Kadir Kotil

    2011-01-01

    Full Text Available Anterior odontoid screw fixation or posterior C1-2 fusion techniques are routinely used in the treatment of Type II odontoid fractures, but these techniques may be inadequate in some types of odontoid fractures. In this new technique (Kotil technique, through a posterior bilateral approach, transarticular screw fixation was performed at the non-dominant vertebral artery (VA side and posterior transodontoid fixation technique was performed at the dominant VA side. C1-2 complex fusion was aimed with unilateral transarticular fixation and odontoid fixation with posterior transodontoid screw fixation. Cervical spinal computed tomography (CT of a 40-year-old male patient involved in a motor vehicle accident revealed an anteriorly dislocated Type II oblique dens fracture, not reducible by closed traction. Before the operation, the patient was found to have a dominant right VA with Doppler ultrasound. He was operated through a posterior approach. At first, transarticular screw fixation was performed at the non-dominant (left side, and then fixation of the odontoid fracture was achieved by directing the contralateral screw (supplemental screw medially and toward the apex. Cancellous autograft was scattered for fusion without the need for structural bone graft or wiring. Postoperative cervical spinal CT of the patient revealed that stabilization was maintained with transarticular screw fixation and reduction and fixation of the odontoid process was achieved completely by posterior transodontoid screw fixation. The patient is at the sixth month of follow-up and complete fusion has developed. With this new surgical technique, C1-2 fusion is maintained with transarticular screw fixation and odontoid process is fixed by concomitant contralateral posterior transodontoid screw (supplemental screw fixation; thus, this technique both stabilizes the C1-2 complex and fixes the odontoid process and the corpus in atypical odontoid fractures, appearing as an

  7. Bioglass 45S5 transformation and molding material in the processing of biodegradable poly-DL-lactide scaffolds for bone tissue engineering

    Science.gov (United States)

    Abdollahi, Sara

    When bone is damaged, a scaffold can temporarily replace it in the site of injury and incite bone tissue to repair itself. A biodegradable scaffold resorbs into the body, generating non-toxic degradation products as new tissue reforms; a bioactive scaffold encourages the surrounding tissue to regenerate. In the present study, we make composite biodegradable and bioactive scaffolds using poly-DL-lactide (PDLLA), a biodegradable polymer, and incorporate Bioglass 45S5 (BG) to stimulate scaffold bioactivity. BG has an interesting trait when immersed in body fluid, a layer of hydroxycarbonate apatite, similar to the inorganic component of bone, forms on its surface. It is of utmost importance to understand the fate of BG throughout the scaffold’s processing in order to assess the scaffold’s bioactivity. In this study, the established different stages of BG reactivity have been verified by monitoring pH during BG dissolution experiments and by conducting an elemental analysis using inductively coupled plasma optical emission spectroscopy (ICP-OES). The composite scaffolds are synthesized by the solvent casting and particulate leaching technique and their morphology assessed by scanning electron microscopy (SEM). To understand the transformations occurred in BG during scaffold synthesis, BG as received, as well BG treated in acetone and water (the fluids involved in scaffold processing) are characterized by Fourier transform infrared (FTIR), and x-ray photoelectron spectroscopy (XPS). The results are then compared with BG extracted from scaffolds after processing. BG has been determined to start reacting during the scaffold processing. In addition, its reactivity is influenced by BG particle size. The study suggests that the presence of the polymer provides a reactive environment for BG due to pH effects. Teflon molds in scaffold fabrication are inert and biocompatibile, but their stiffness presents a challenge during de-molding. Silicone-based and polyurethane molds

  8. Bone healing and mineralization, implant corrosion, and trace metals after nickel-titanium shape memory metal intramedullary fixation.

    Science.gov (United States)

    Ryhänen, J; Kallioinen, M; Serlo, W; Perämäki, P; Junila, J; Sandvik, P; Niemelä, E; Tuukkanen, J

    1999-12-15

    Its shape memory effect, superelasticity, and good wear and damping properties make the NiTi shape memory alloy a material with fascinating potential for orthopedic surgery. It provides a possibility for making self-locking, self-expanding, and self-compressing implants. Problems, however, may arise because of its high nickel content. The purpose of this work was to determine the corrosion of NiTi in vivo and to evaluate the possible deleterious effects of NiTi on osteotomy healing, bone mineralization, and the remodeling response. Femoral osteotomies of 40 rats were fixed with either NiTi or stainless steel (StSt) intramedullary nails. The rats were killed at 2, 4, 8, 12, 26, and 60 weeks. Bone healing was examined with radiographs, peripheral quantitative computed tomography, (pQCT) and histologically. The corrosion of the retrieved implants was analyzed by electron microscopy (FESEM). Trace metals from several organs were determined by graphite furnace atomic absorption spectrometry (GF-AAS) or by inductively coupled plasma-atomic emission spectrometry (ICP-AES). There were more healed bone unions in the NiTi than in the StSt group at early (4 and 8 weeks) time points. Callus size was equal between the groups. The total and cortical bone mineral densities did not differ between the NiTi and StSt groups. Mineral density in both groups was lower in the osteotomy area than in the other areas along the nail. Density in the nail area was lower than in the proximal part of the operated femur or the contralateral femur. Bone contact to NiTi was close. A peri-implant lamellar bone sheet formed in the metaphyseal area after 8 weeks, indicating good tissue tolerance. The FESEM assessment showed surface corrosion changes to be more evident in the StSt implants. There were no statistically significant differences in nickel concentration between the NiTi and StSt groups in any of the organs. NiTi appears to be an appropriate material for further intramedullary use because it

  9. In vitro responses of bone-forming MC3T3-E1 pre-osteoblasts to biodegradable Mg-based bulk metallic glasses.

    Science.gov (United States)

    Li, Haifei; He, Wei; Pang, Shujie; Liaw, Peter K; Zhang, Tao

    2016-11-01

    In light of the superior property profile of favorable biocompatibility, proper corrosion/degradation behavior and good mechanical properties, Mg-based bulk metallic glasses (BMGs) are considered as potential biodegradable biomaterials. In the present study, in vitro responses of bone-forming MC3T3-E1 pre-osteoblasts to Mg-Zn-Ca-Sr BMGs were studied in order to assess their feasibility to serve as orthopedic implants. The Mg-Zn-Ca-Sr BMGs were much more capable of supporting cell adhesion and spreading in comparison with crystalline AZ31B Mg alloy. The Mg-Zn-Ca-Sr BMG extracts showed no cytotoxicity to and slightly stimulated the proliferation of pre-osteoblasts. The cells cultured in 100% BMG extracts exhibited lower alkaline phosphatase activity as compared with that in negative control, which could be mainly ascribed to the inhibition of high concentrations of Zn ions on cell differentiation. With decreasing the extract concentration, the inhibitory effect was diminished and the 5% BMG extract exhibited slight stimulation in cell differentiation and mineralization. The high corrosion resistance of BMGs contributed to smaller environmental variations, compared with AZ31B alloy, thus lowering the unfavorable influences on cellular responses. A comparison among the biodegradable Mg-, Ca- and Sr-based BMGs for their biomedical applications is presented. PMID:27524063

  10. Low bone mineral density is not related to failure in femoral neck fracture patients treated with internal fixation

    DEFF Research Database (Denmark)

    Viberg, Bjarke; Ryg, Jesper; Overgaard, Søren;

    2014-01-01

    new hip fracture). A stratified Cox regression model on fracture displacement was applied and adjusted for age, sex, quality of reduction, implant positioning, comorbidity, and walking disability. Results - 49 patients had a T-score below -2.5 (standard deviation from the young normal reference mean......, implant positioning, and quality of reduction. From a questionnaire completed during admission, 2 variables for comorbidity and walking disability were chosen. Primary outcome was low hip BMD (amount of mineral matter per square centimeter of hip bone) compared to hip failure (resection, arthroplasty, or...

  11. A laboratory investigation to assess the influence of cement augmentation of screw and plate fixation in a simulation of distal femoral fracture of osteoporotic and non-osteoporotic bone.

    Science.gov (United States)

    Wähnert, D; Lange, J H; Schulze, M; Gehweiler, D; Kösters, C; Raschke, M J

    2013-10-01

    The augmentation of fixation with bone cement is increasingly being used in the treatment of severe osteoporotic fractures. We investigated the influence of bone quality on the mechanics of augmentation of plate fixation in a distal femoral fracture model (AO 33 A3 type). Eight osteoporotic and eight non-osteoporotic femoral models were randomly assigned to either an augmented or a non-augmented group. Fixation was performed using a locking compression plate. In the augmented group additionally 1 ml of bone cement was injected into the screw hole before insertion of the screw. Biomechanical testing was performed in axial sinusoidal loading. Augmentation significantly reduced the cut-out distance in the osteoporotic models by about 67% (non-augmented mean 0.30 mm (sd 0.08) vs augmented 0.13 mm (sd 0.06); p = 0.017). There was no statistical reduction in this distance following augmentation in the non-osteoporotic models (non-augmented mean 0.15 mm (sd 0.02) vs augmented 0.15 mm (sd 0.07); p = 0.915). In the osteoporotic models, augmentation significantly increased stability (p = 0.017). PMID:24078541

  12. Bone cement and bone grafting in nail path to strengthen dynamic hip screw fixation for senile osteoporotic intertrochanteric fracture%骨水泥、钉道植骨强化动力髋螺钉固定修复老年骨质疏松性股骨转子间骨折

    Institute of Scientific and Technical Information of China (English)

    林周胜; 孙鸿涛; 夏雄智; 江成; 黎飞猛

    2015-01-01

    背景:对于老年骨质疏松性髋部骨折的动力髋螺钉固定,如能避免使用过程中造成的骨量丢失,或是采用其他手段增加固定螺钉把持力,将改善动力髋螺钉固定的治疗效果。目的:对比研究3种固定方式修复老年骨质疏松性股骨转子间骨折的效果。方法:回顾性分析近5年来采用常规动力髋螺钉内固定、骨水泥强化后动力髋螺钉固定及主钉道压配植骨配合动力髋螺钉固定3种固定方式治疗老年骨质疏松性股骨转子间骨折患者的资料,分别设为对照组、骨水泥组和植骨组。结果与结论:经固定后2年随访,植骨组、骨水泥组和对照组Harris髋关节功能评分优良率分别为95%,80%,70%。植骨组骨折临床愈合时间明显缩短(P <0.05),出现螺钉固定失败情况与骨水泥组相当。对照组较其他2组相对更多出现退钉等内固定失败情况。结果表明,与其他常规动力髋螺钉内固定、骨水泥强化后动力髋螺钉固定方式相比较,主钉道压配植骨配合动力髋螺钉内固定的疗效及安全性更好。%BACKGROUND:In dynamic hip screw fixation for treating aged osteoporotic intertrochanteric fracture, avoiding the loss of bone mass, or by other means that can increase the fixed screw pulout strength, wil improve the therapeutic effect of dynamic hip screw fixation. OBJECTIVE: To compare the effects of three kinds of repair methods on aged osteoporotic intertrochanteric fracture. METHODS:Data of aged osteoporosis intertrochanteric fracture patients, who received conventional dynamic hip screw fixation, bone cement augmentation with dynamic hip screw fixation and bone grafting with dynamic hip screw fixation, were retrospectively analyzed. They were divided into control group, bone cement group and bone grafting group. RESULTS AND CONCLUSION:After two years of folow-up, the excelent and good rates of Harris hip function were 95%, 80% and 70% in

  13. Relationship of shape and structure of internal fixation implant to biomechanics following bone injury%骨损伤内固定植入物形状和结构与生物力学的关系

    Institute of Scientific and Technical Information of China (English)

    杨君建

    2012-01-01

    背景 实践证明内固定材料良好的生物力学性能对受损骨的治疗效果影响较大,而通过改善内固定材料的形状和结构可以实现较好的力学效果.目的 以骨科置入内固定材料的生物力学特征为视角,分析与阐述骨科植入物的形状和结构与内固定效果的关系.方法 应用计算机检索PubMed、维普和万方数据库中1990-01/2011-12 关于骨损伤治疗及其内固定材料学方面的文章,在标题和摘要中以"骨,固定,形状,材料"或"bone,fixed,shape,material"为检索词进行检索,排除重复研究、普通综述或Meta 分析类文章.初检得到156 篇文献,根据纳入标准选择26 篇文章进行综述.结果与结论 骨科植入物材料的生物力学性能对骨的固定、骨血供以及成骨细胞的成长和再生起着重要的制约因素,而材料形状和结构的改变会对其生物力学性能产生较大的影响进而影响治疗效果.如何运用新工艺对骨科植入物材料的形状或结构进行改善,通过对其进行巧妙的物理改性以达到理想的内固定治疗效果应成为研究者关注的问题.%BACKGROUND: Good biomechanical property of internal fixation material has great effects on therapeutic outcomes of damaged bone. Good mechanics outcomes can be obtained by improving the shape and structure of internal fixation material. OBJECTIVE: From the view angle of biomechanical feature of orthopedic implant internal fixation material, to analyze the correlation of shape and structure of orthopedic implant and internal fixation outcomes.METHODS: We retrieved PubMed, Vip and Wanfang Database for articles concerning bone injury treatment and internal fixation material published from January 1990 to December 2011. The key words were “bone, fixation, shape, material”, which were searched in titles and abstracts. The articles addressing repetitive studies, common reviews or Meta analysis were excluded. A total of 156 articles were

  14. A biodegradable antibiotic-impregnated scaffold to prevent osteomyelitis in a contaminated in vivo bone defect model

    Directory of Open Access Journals (Sweden)

    JS McLaren

    2014-06-01

    Full Text Available Open fractures are at risk of serious infection and, if infected, require several surgical interventions and courses of systemic antibiotics. We investigated a new injectable formulation that simultaneously hardens in vivo to form a porous scaffold for bone repair and delivers antibiotics at high concentrations to the local site of infection. Duration of antimicrobial activity against Staphylococcus aureus was determined using the serial plate transfer test. Ultimate compressive strength and porosity of the material was measured with and without antibiotics. The material was evaluated in vivo in an ovine medial femoral condyle defect model contaminated with S. aureus. Sheep were sacrificed at either 2 or 13 weeks and the defect and surrounding bone assessed using micro-computed tomography and histology. Antimicrobial activity in vitro persisted for 19-21 days. Sheep with antibiotic-free material and bacteria became infected, while those with antibiotic-containing material and bacteria did not. Similarly, new bone growth was seen in uninoculated animals with plain polymer, and in those with antibiotic polymer with bacteria, but not in sheep with plain polymer and bacteria. The antibiotic-impregnated scaffolds were effective in preventing S. aureus infections whilst supporting bone growth and repair. If translated into clinical practice, this approach might reduce the need for systemic antibiotics.

  15. A biodegradable antibiotic-impregnated scaffold to prevent osteomyelitis in a contaminated in vivo bone defect model.

    Science.gov (United States)

    McLaren, J S; White, L J; Cox, H C; Ashraf, W; Rahman, C V; Blunn, G W; Goodship, A E; Quirk, R A; Shakesheff, K M; Bayston, R; Scammell, B E

    2014-01-01

    Open fractures are at risk of serious infection and, if infected, require several surgical interventions and courses of systemic antibiotics. We investigated a new injectable formulation that simultaneously hardens in vivo to form a porous scaffold for bone repair and delivers antibiotics at high concentrations to the local site of infection. Duration of antimicrobial activity against Staphylococcus aureus was determined using the serial plate transfer test. Ultimate compressive strength and porosity of the material was measured with and without antibiotics. The material was evaluated in vivo in an ovine medial femoral condyle defect model contaminated with S. aureus. Sheep were sacrificed at either 2 or 13 weeks and the defect and surrounding bone assessed using micro-computed tomography and histology. Antimicrobial activity in vitro persisted for 19-21 days. Sheep with antibiotic-free material and bacteria became infected, while those with antibiotic-containing material and bacteria did not. Similarly, new bone growth was seen in uninoculated animals with plain polymer, and in those with antibiotic polymer with bacteria, but not in sheep with plain polymer and bacteria. The antibiotic-impregnated scaffolds were effective in preventing S. aureus infections whilst supporting bone growth and repair. If translated into clinical practice, this approach might reduce the need for systemic antibiotics. PMID:24908426

  16. Comparative study of safety and efficacy of electrocautery blade with cold scalpel blade for skin opening during fixation of fracture of forearm bone with plate and screws

    Directory of Open Access Journals (Sweden)

    K T Madhukar

    2012-01-01

    Full Text Available Introduction: The art of performing surgeries have improved in recent years with the development of various electrosurgical devices assisting surgeons in performing safer surgeries with better outcomes. Skin incision has traditionally been made with a standard scalpel blade with good primary healing end results of the wound. The electrocautery has been used safely in performing deeper dissections. Use of electrocautery in skin incision has been discouraged in the past for the fear of cutaneous scarring, wound dehiscence, and infections particularly in orthopedic surgeries using internal implants. A review of the literature shows not many studies have been conducted to evaluate the safety and efficacy of electrocautery in skin incisions during orthopedic surgeries using internal implants. Aim: A prospective study was conducted in a tertiary care hospital with the aim to determine whether an electrocautery blade can be used safely for skin incisions. Materials and Methods: Sixty-two patients with single-bone fracture of the forearm undergoing open reduction and internal fixation received one-half of the incision with a standard scalpel blade and another half with electrocautery in pure cutting mode randomly. Analysis: Wounds were compared on operating day for any physical changes and on days 3, 5, and 12, and again on 3 rd and 6 weeks follow-up to know any difference in skin healing between the incised wounds of the two halves. Results: No evidence of any difference in healing of the two halves of skin incision was noted. There was also no increased risk of wound scarring, dehiscence, or infection with electrocautery incision when compared with standard scalpel incision. The time taken for skin incision with electrocautery was significantly less when compared with cold scalpel incision. Conclusion: We propose that electrocautery can be safely used for performing skin incision, with comparable results to that of a standard scalpel skin incision.

  17. A biodegradable antibiotic-impregnated scaffold to prevent osteomyelitis in a contaminated in vivo bone defect model

    OpenAIRE

    JS McLaren; LJ White; HC Cox; Ashraf, W; CV Rahman; GW Blunn; AE Goodship; RA Quirk; KM Shakesheff; Bayston, R; BE Scammell

    2014-01-01

    Open fractures are at risk of serious infection and, if infected, require several surgical interventions and courses of systemic antibiotics. We investigated a new injectable formulation that simultaneously hardens in vivo to form a porous scaffold for bone repair and delivers antibiotics at high concentrations to the local site of infection. Duration of antimicrobial activity against Staphylococcus aureus was determined using the serial plate transfer test. Ultimate compressive strength and ...

  18. Development of bioactive glass based scaffolds for controlled antibiotic release in bone tissue engineering via biodegradable polymer layered coating

    OpenAIRE

    Nooeaid, Patcharakamon; Li, Wei; Roether, Judith A.; Mourino, Viviana; Goudouri, Ourania-Menti; Schubert, Dirk W.; Boccaccini, Aldo R.

    2014-01-01

    Highly porous 45S5 Bioglass®-based scaffolds coated with two polymer layers were fabricated to serve as a multifunctional device with controlled drug release capability for bone regeneration applications. An interior poly(D,L-lactide)/poly(ethylene glycol)-(polypropylene glycol)-poly(ethylene glycol) triblock copolymer (Pluronic P123) coating improved the mechanical stability of Bioglass-based scaffolds, while an exterior natural polymer (alginate or gelatin) coating served as an antibiotic d...

  19. 骨水泥强化椎弓根螺钉固定L1压缩性骨折:与单纯椎弓根螺钉固定的比较%Pedicle screw fixation with bone cementversus pedicle screw fixation alone for L1 compression fractures

    Institute of Scientific and Technical Information of China (English)

    亚力坤•亚森

    2015-01-01

    背景:椎体成形术与椎弓根螺钉内固定都是胸腰椎骨折的有效修复方案,但胸腰椎压缩性骨折内固定取出后脊柱角度丢失是较为常见的并发症,经皮椎体成形术可能是预防脊柱角度丢失的较好选择。  目的:观察骨水泥强化椎弓根螺钉置入内固定修复L1压缩性骨折的临床疗效及并发症,并与单纯椎弓根螺钉内固定比较。  方法:纳入L1压缩性骨折患者76例,根据内固定修复方案分为两组,经皮椎体成形组40例行骨水泥联合椎弓根螺钉置入内固定治疗,单纯椎弓根内固定组36例仅行椎弓根螺钉置入内固定治疗。比较两组的修复效果,置入后即刻、置入后3,6个月以伤椎为中心进行MRI检查测量Cobb角、伤椎椎体前缘高度,同时记录目测类比评分;另外了解有无内固定松动断裂。  结果与结论:两组患者随访6个月内均获骨性愈合,无螺钉松动、折断。两组置入后6个月损伤节段后凸Cobb角、伤椎椎体前缘高度均较置入前明显改善(P0.05)。表明应用骨水泥强化椎弓根螺钉内固定及椎弓根钉内固定修复L1压缩性均可获得满意复位,重建椎体高度。但抗压稳定性结果表明应用骨水泥强化椎弓根螺钉内固定的固定效果更好一些,未见短期断钉、矫正丢失等并发症,椎体骨水泥灌注可提高椎弓根螺钉置入后的稳定性。%BACKGROUND:Vertebroplasty and edicle screw fixation are effective repair methods for thoracolumbar fractures. Spine angle loss is a more common complication after removal of implant for thoracolumbar compression fractures. Percutaneous vertebroplasty may be a better choice for preventing spine angle loss. OBJECTIVE:To investigate the clinical curative effect and complication of pedicle screw fixation with bone cement for repair of L1 compression fractures, and to compare with pedicle screw fixation alone. METHODS: A total

  20. Bone transportion by composite external fixator on refractory chronic osteomyelitis of femur%组合式外固定架骨搬运术治疗难治性股骨慢性骨髓炎疗效评价

    Institute of Scientific and Technical Information of China (English)

    海国栋; 张春雷

    2014-01-01

    Objective To evaluate the clinical effect of bone transport by composite external fixator on chronic osteomyelitis of femur. Methods Thirteen patients with bone defect of femur after chronic osteomyelitis were treated by bone transport with composite external fixator. The mean length of the bone defect was 8. 7 cm. Results All patients were followed up for 21-32 months. The bone lengthening area grew well,the length of callus distraction was 6. 8~14. 5 cm,and the mean radiographic con-solidation index was 19. 7 d/cm. According to the Paley’s criteria,the healing effect of 10 cases was excellent,and that of the rest 3 cases was good. The functional recovery of 9 cases was excellent,and that of the rest 4 cases was good. Conclusion Bone trans-port by composite external fixator is a reliable method in the reconstruction of bone defect caused by chronic osteomyelitis.%目的:评价应用组合式外固定架骨搬运术治疗股骨慢性骨髓炎的临床疗效。方法应用组合式外固定架骨搬运技术治疗13例股骨慢性骨髓炎清除后骨缺损,平均骨缺损长度8.7 cm。结果随访21~32个月,骨缺损接触并全部愈合,骨延长区骨生长满意,切口一期愈合,窦道和骨外露消失。骨延长6.8~14.5 cm,平均外固定指数19.7 d/cm。依据Paley 的评定标准进行骨愈合评定,优为11例,良为2例;功能评定优为9例,良为4例。结论组合式外固定架骨搬运术是治疗难治性股骨慢性骨髓炎可靠方法。

  1. Femoral Reconstruction Using External Fixation

    Directory of Open Access Journals (Sweden)

    Yevgeniy Palatnik

    2011-01-01

    Full Text Available Background. The use of an external fixator for the purpose of distraction osteogenesis has been applied to a wide range of orthopedic problems caused by such diverse etiologies as congenital disease, metabolic conditions, infections, traumatic injuries, and congenital short stature. The purpose of this study was to analyze our experience of utilizing this method in patients undergoing a variety of orthopedic procedures of the femur. Methods. We retrospectively reviewed our experience of using external fixation for femoral reconstruction. Three subgroups were defined based on the primary reconstruction goal lengthening, deformity correction, and repair of nonunion/bone defect. Factors such as leg length discrepancy (LLD, limb alignment, and external fixation time and complications were evaluated for the entire group and the 3 subgroups. Results. There was substantial improvement in the overall LLD, femoral length discrepancy, and limb alignment as measured by mechanical axis deviation (MAD and lateral distal femoral angle (LDFA for the entire group as well as the subgroups. Conclusions. The Ilizarov external fixator allows for decreased surgical exposure and preservation of blood supply to bone, avoidance of bone grafting and internal fixation, and simultaneous lengthening and deformity correction, making it a very useful technique for femoral reconstruction.

  2. Biodegradable Polymers

    OpenAIRE

    Isabelle Vroman; Lan Tighzert

    2013-01-01

    Biodegradable materials are used in packaging, agriculture, medicine and other areas. In recent years there has been an increase in interest in biodegradable polymers. Two classes of biodegradable polymers can be distinguished: synthetic or natural polymers. There are polymers produced from feedstocks derived either from petroleum resources (non renewable resources) or from biological resources (renewable resources). In general natural polymers offer fewer advantages than synthetic polymers. ...

  3. Strain-stress analysis of lower limb with applied fixator

    Directory of Open Access Journals (Sweden)

    Mrázek M.

    2010-07-01

    Full Text Available This paper compares physiological state of tibia before and after application of an external fixator. The fixator systems’ models but also model of tibia are loaded in the direction of body axis. The paper is focused on the examination of differences in stiffness before and after the application of fixation. Two types of axial external fixators are compared. Both fixators differ in their construction. The first fixator is two-frame and fixation rods are used for fixing the bone tissue (variant I. The second one is fixed into tibia with screws (variant II. We have found out that the two-frame external fixator has much bigger stiffness during limb fixation than the fixator with one body. Much higher deformations compared to physiological state of tibia occur in the variant II.

  4. Synthesis of Chiral Oligomer-Grafted Biodegradable Polyurethanes and Their Chiral-Dependent Influence on Bone Marrow Stem Cell Behaviors.

    Science.gov (United States)

    Hu, Bin; Deng, Jun; Zheng, Honghao; Yu, Shan; Gao, Changyou

    2016-08-01

    Chirality is one of the most fascinating and ubiquitous features in nature, especially in biological systems. The effects of chiral surfaces, especially in combination with degradable materials of good biocompatibility, on stem cell behaviors has not yet been tackled. In this communication, the chiral monomers N-acryloyl-l(d)-valine (l(d)-AV) are synthesized and are polymerized to obtain chiral (l(d)-PAV-SH) oligomers, which are covalently immobilized onto electron-deficient poly(propylene fumarate) polyurethane (PPFU) via Michael addition. The PPFU-l-PAV can interact more strongly and actively with bone marrow stem cells (BMSCs) than PPFU-d-PAV, leading to a larger cell spreading area, faster migration velocity, and stronger osteodifferentiation tendency. PMID:27295370

  5. Biodegradable polymers in clinical use and clinical development

    CERN Document Server

    Domb, Abraham J

    2011-01-01

    The definitive guide to biodegradable polymer science-where we are and what's to come The most comprehensive review of biodegradable polymers already utilized or under development for clinical use, Biodegradable Polymers in Clinical Use and Clinical Development looks at the state of biodegradable polymers now and over the next five years. Implantable molecules that break down within the body over a predetermined period of time, biodegradable polymers have been employed as drug carriers, orthopedic fixation devices, and absorbable sutures. Yet while hundreds of such polymers have been deve

  6. Suspensory Anterior Tibial Fixation in the Anatomic Transtibial Posterior Cruciate Ligament Reconstruction

    OpenAIRE

    Elazab, Ashraf; Lee, Yong Seuk; Kang, Seo Goo

    2016-01-01

    The transtibial technique is the most relevant among many surgical techniques for posterior cruciate ligament reconstruction, and many types of fixation devices are used for tibial fixation according to the technique and the length of the graft. However, bone density in the fixation areas should be taken into consideration when choosing the fixation device to achieve rigid and stable fixation. However, density is not a substantial issue for anteromedial cortical fixation using a cortical susp...

  7. 不同固定、脱钙方式对骨组织常规制片的影响%The Influence of Different Way of Fixation and Decalcification on the Conventional Slide of Bone Tissue

    Institute of Scientific and Technical Information of China (English)

    万俊峰; 王影; 侯俊

    2012-01-01

    目的 通过对骨标本不同固定和脱钙方式的比较,探索适合于骨标本的固定和脱钙方式.方法 分别采取先固定后脱钙、同时固定加脱钙和先脱钙后固定这三种方式对50例长骨肿瘤标本进行对比分析.结果 先固定后脱钙组常规HE染色效果优于同步固定脱钙组,但两组比较差异无统计学意义(P>0.05),该两组常规染色效果均明显优于先脱钙后固定组(P 0. 05) . The routine HE staining results of the DAF and DWF group were better than that of the DBF group with significantly difference(P <0. 01) . Conclusion; For the routine HE slide of bone tissue, the way of fixation is very important. Decalcification should be conducted before fixation or performed simultaneously with fixation. The DBF methodis not recommended.

  8. Effect of plaster external fixation on the histomorphological changes for bone-tendon junction healing%石膏外固定修复兔髌骨-腱连接点断裂的组织形态学变化

    Institute of Scientific and Technical Information of China (English)

    王靖; 张朝跃; 谭财福

    2012-01-01

    BACKGROUND: Plaster external fixation has a positive effect on bone-tendon junction healing, but there is no in-depth study on the repair mechanism.OBJECTIVE: To investigate the effect of plaster external fixation on the histomorphological changes for bone-tendon junction healing.METHODS: The bone-tendon junction healing models were established by cutting off the junction between the patellar tip and the patellar tendon as well as the distal part of the patella. The models were divided into experimental group and model group. The models in the experimental group were performed with plaster external fixation and those in the model group were without fixation. Each group got the sample at 2, 4 and 8 weeks after operation.RESULTS AND CONCLUSION: Hematoxylin-eosin staining, Safranin'O staining, macrophages immunohistochemistry staining and integral absorbance showed that the tissue edema and adhesion at the bone-tendon junction in the experimental group were better than those in the model group, cartilage cells and bone tissue formation and differentiation in the experimental group were significantly better those those in the model group, and degree of the inflammation in the experimental group was light and disappeared quickly. External fixation can accelerate the process of bone-tendon repair and promote the healing.%背景 石膏外固定对髌骨-腱连接点断裂的治疗作用肯定,但相关修复机制一直未有深入研究.目的 观察石膏外固定对髌骨-腱连接点断裂修复的组织形态学改变.方法 切断髌尖与髌腱连接处并切除远端部分髌骨建立兔髌骨-腱连接点损伤模型,实验组在造模的基础上给予石膏外固定,模型组不予固定,分别在造模后2,4,8 周取材.结果与结论 苏木精-伊红染色、Safranin'O 染色和巨噬细胞免疫组化染色及其积分吸光度检测均显示实验组造模后骨-腱结合部组织修复快,软骨细胞及骨组织的形成、分化明显优于模型组,

  9. External fixation combined with limited internal flxation and bone grafting for Pilon fracture%有限内固定结合外固定架治疗胫骨远端 Pilon骨折临床观察

    Institute of Scientific and Technical Information of China (English)

    刘建; 刘俊宾; 王文珠; 郑卫东

    2014-01-01

    目的:观察有限内固定结合外固定架治疗胫骨Pilon骨折的临床效果。方法采用三维单侧多功能外固定支架结合有限切开内固定治疗Ruedi和Allgower分型中Ⅱ、Ⅲ型有移位骨折57例。结果根据Pi-lon骨折复位的Burwell-Charnley放射学标准及踝关节主观评分结果示,优45例,良10例,差2例。术后并发症:4例感染,3例皮肤坏死,2例发生骨筋膜综合征,5例踝关节功能障碍但未见骨不连或畸形愈合。结论根据Pilon骨折的类型和软组织损伤程度选择合适的手术方式和手术时机,合理使用外固定支架结合有限内固定维持骨折复位和下肢力线,干骺端缺损区充分植骨,整复关节面,适当功能锻炼,晚负重,术后可达到良好的临床效果。%Objective To investigate the clinical efficacy of external fixation combined with limited internal fixation and bone graft for the treatment of Pilon fractures .Methods Fifty-seven patients of Ruedi and AllgowerⅡ ,Ⅲ type of displaced fracture from March 2008 to October 2013 had treated with external fixation combined with limited internal flxation and bone grafting .Results According to Mazur function assessment system ,the curative effect was excellent in 45 patients ,good in 10 patients and poor in 2 patients .The complications included wound in-fection in 4 cases ,skin necrosis in 3 cases ,fascia syndrome in 2 cases and functional disturbance of ankle in 5 cases . Conclusion Accurate assess local soft tissue conditions for Pilon fractures is essential .According to Pilon fracture type and degree of soft tissue injury ,appropriate surgical method and surgical opportunity can be selected .External fixation combined with limited internal fixation and bone grafting maintains fracture reduction and mechanical axis of lower limb .Metaphyseal bone defect area can be filled with autogenous bone or artificial bone to prompt restora-tion of articular surface .Appropriate

  10. Options for acetabular fixation surfaces.

    Science.gov (United States)

    Klika, Alison K; Murray, Trevor G; Darwiche, Hussein; Barsoum, Wael K

    2007-01-01

    Aseptic loosening is the most common cause for revision total hip arthroplasty (THA). Due to poor long-term results with cemented acetabular components, cementless implants that rely on biologic fixation became popular in the United States for both primary and revision procedures in the early 1980s. Cementless acetabular components used in THA have been reported to have superior radiographic performance compared with cemented fixation, although the optimal method of acetabular fixation remains controversial. Cementless acetabular components require initial implant stability to allow for bone ingrowth and remodeling into the acetabular shell, providing long-term durability of the prosthesis. Many improved implant materials are available to facilitate bone growth and remodeling, including the 3 most common surface treatments; fibermesh, sintered beads, and plasma spray coatings. Recently added to these are porous metal surfaces, which have increased porosity and optimal pore sizes when compared with titanium fibermesh. The most studied of these materials is the titanium fibermesh fixation surface, which has demonstrated a mechanical failure rate of 1% at 10 to 15 years. This technology utilizes the diffusion bonding process to attach fiber metal pads to a titanium substrate using heat and pressure. The sintered bead fixation surface offers a porous coating of various sizes of spherical beads, achieved by the sintering process, and has been shown to provide long-term fixation. While there are less long-term published data regarding the titanium plasma spray surface, its early results have provided evidence of its durability, even in the face of significant osteolysis. The most recently added alternative fixation surface is porous tantalum metal, which offers potentially greater bone ingrowth and bone graft incorporation due to its high porosity (80%) and low modulus of elasticity (3 MPa). Porous tantalum implants have shown early favorable clinical results and have

  11. Assessment of the influence of Laser phototherapy on the bone repair process of complete fractures in tibiae of rabbits stabilized with semi-rigid internal fixation treated with or without MTA graft: a histological study

    Science.gov (United States)

    Soares, Luiz G. P.; Silva, Aline C. P.; Silva, Anna Paula L. T.; Neves, Bruno Luiz R. C.; Santos, Nicole R. S.; dos Santos, Jean N.; Pinheiro, Antonio L. B.

    2016-03-01

    Beside biomaterials, Laser phototherapy has shown positive effects as auxiliary therapy in bone repair process, especially when involving large bone losses. The aim of this histological study was to evaluate, by light microscopy, the influence of laser phototherapy on the repair of complete tibial fractures in rabbits treated or not with semi-rigid internal fixation and Mineral Trioxide Aggregate - MTA graft. Twelve Rabbits were randomly divided into four groups with three animals each. After general anesthesia, complete fractures were created in one tibia with a carborundum disk. All animals (groups I-IV) had the fracture stabilized with semi-rigid fixation (wire osteosynthesis - WO). Group I was routinely fixed with WO; groups II and IV fracture was filled by blood clot and MTA implant. In Groups III and IV fracture was filled by blood clot and further irradiated with laser (λ780 nm, 70 mW, CW, Φ = 0.04 cm2, 20.4 J/cm2, per session, t = 300s, 142.8 J/cm2 per treatment). The phototherapy protocol was applied immediately after the surgery and repeated each 48 hours during 15 days. Animal death occurred on the 30th postoperative day. After removal of the specimens, the samples were routinely processed, stained with HE and evaluated by light microscopy. Histologically, the group treated with MTA graft and irradiated with laser showed the fracture filled by a more organized and mature trabecular bone, when compared with all other groups. From the results of the present study, it may be concluded that the association of Laser phototherapy + MTA graft in fractures treated with WO improved bone repair when compared with fractures treated only with WO.

  12. Modeling in vivo corrosion of AZ31 as temporary biodegradable implants. Experimental validation in rats

    International Nuclear Information System (INIS)

    In this paper, two complementary approaches, mathematical modeling and experimental results are combined to identify variables that affect the in vivo biodegradation of magnesium implants. The in vivo corrosion behavior of AZ31 alloy proposed for temporary applications as fixation of bone fractures has been modeled solving the Laplace equation by finite element method (FEM). Bar-shaped AZ31 implants of 1 mm diameter and 20 mm length were inserted in Wistar rat femurs with and without a fracture. The presence of gas around AZ31 implants inside the femurs has been detected in situ at the epiphysis and in fractured areas by computerized tomography (CT). Examining some in vivo conditions, the model confirms that magnesium-alloy devices have different biodegradation behavior, depending on the thickness of electrolyte at the implantation site and can be used for predicting the biodegradation behavior. - Highlights: • Modeling of AZ31 corrosion by solving the Laplace by finite element method • Electrolyte thickness is a key factor in the in vivo corrosion of magnesium alloys. • A critical thickness below which corrosion is focused around impurities is identified. • The critical value is less evident in a material with a high number of impurities. • Experimental and numerical results explain the biodegradation of magnesium implants

  13. Biomechanical evaluation of fixation degree of fragments by periosteal osteosynthesis

    Directory of Open Access Journals (Sweden)

    Barabash Yu.A.

    2010-09-01

    Full Text Available Expansion of indications for surgery and plate osteosynthesis of long bones points to increased number of complications caused by instability of fragments, that can be associated in their turn with constructive features or iatrogenic factors. Insufficient rigidity of fragment fixation is due to incorrect technical treatment and wrong choice of fixator. Biomechanical parameters of periosteal fixation rigidity have been experimentally proved, depending on fixator lever

  14. Biodegradation of Absorbable Hydroxyapatite/Poly-DL-lactide Composites in Different Environment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To develop a new generation of absorbable fracture fixation devices with enhanced biocompatibility, the biodegradation mechanism and its influence on the cellular response at the tissue/implant interface of hydroxyapatite/ poly-DL-lactide (HA/PDLLA) composites were investigated in vitro and in vivo.HA/PDLLA rods were immersed in phosphate-buffered saline,or implanted in muscle and bony tissue for 52 weeks.Scanning electron microscopic and histological studies were done.The degradation rate was the slowest in vitro,slower in muscle tissue and fast in bone.In vitro, the composites degraded heterogeneously and a hollow structure was formed.In bone,the limited clearing capacity leads to the accumulation of oligomeric debris,which contribute totally to the autocatalytic effect.So,the fastest degradation and intense tissue response were seen.In muscle tissue,oligomeric debris migrated into vicinal fibers over a long distance from the original implant cavity and the tissue reactions were,however, quite moderate.For the same size organic/inorganic composite,the environment where it was placed is the major factor in determining its biodegradation process and cellular reaction.In living tissue,factors such as cells,enzymes and mechanical stress have an obvious influence on the biodegradation and biological process at the tissue/implant interface.The biocompatibility of the HA/PDLLA composites is enhanced with the incorporating of the resorbable HA microparticles.

  15. Augmentation of tendon-to-bone healing.

    Science.gov (United States)

    Atesok, Kivanc; Fu, Freddie H; Wolf, Megan R; Ochi, Mitsuo; Jazrawi, Laith M; Doral, M Nedim; Lubowitz, James H; Rodeo, Scott A

    2014-03-19

    Tendon-to-bone healing is vital to the ultimate success of the various surgical procedures performed to repair injured tendons. Achieving tendon-to-bone healing that is functionally and biologically similar to native anatomy can be challenging because of the limited regeneration capacity of the tendon-bone interface. Orthopaedic basic-science research strategies aiming to augment tendon-to-bone healing include the use of osteoinductive growth factors, platelet-rich plasma, gene therapy, enveloping the grafts with periosteum, osteoconductive materials, cell-based therapies, biodegradable scaffolds, and biomimetic patches. Low-intensity pulsed ultrasound and extracorporeal shockwave treatment may affect tendon-to-bone healing by means of mechanical forces that stimulate biological cascades at the insertion site. Application of various loading methods and immobilization times influence the stress forces acting on the recently repaired tendon-to-bone attachment, which eventually may change the biological dynamics of the interface. Other approaches, such as the use of coated sutures and interference screws, aim to deliver biological factors while achieving mechanical stability by means of various fixators. Controlled Level-I human trials are required to confirm the promising results from in vitro or animal research studies elucidating the mechanisms underlying tendon-to-bone healing and to translate these results into clinical practice. PMID:24647509

  16. Bone

    International Nuclear Information System (INIS)

    Bone scanning provides information on the extent of primary bone tumors, on possible metastatic disease, on the presence of osteomyelitis prior to observation of roentgenographic changes so that earlier therapy is possible, on the presence of collagen diseases, on the presence of fractures not disclosed by x-ray films, and on the evaluation of aseptic necrosis. However, the total effect and contribution of bone scanning to the diagnosis, treatment, and ultimate prognosis of pediatric skeletal diseases is, as yet, unknown. (auth)

  17. 骨水泥强化椎弓根螺钉固定对骨质疏松患者有利无弊?★%Pedicle screw fixation augmented with bone cement benefits osteoporosis patients?

    Institute of Scientific and Technical Information of China (English)

    岳文峰; 夏虹; 王建华

    2013-01-01

    BACKGROUND:During the pedicle screw fixation for lumbar disease patients accompanied with osteoporosis, addition of bone cement in osteoporotic vertebral body can significantly increase the stability of internal fixation, but the effect on adjacent segments is not clear. OBJECTIVE:To observe the effect on adjacent segments of osteoporosis patients after pedicle screw fixation augmented with bone cement in early and medium-term fol ow-up period. METHODS:We reviewed the medical information of 87 patients suffering from lumbar disease accompanied with osteoporosis who underwent operation of pedicle screw fixation and posterior lumbar spinal decompression, and the patients were divided into three groups:conventional pedicle screw group, conventional pedicle screw+bone cement group, novel perfusional pedicle screw+bone cement group. The samples were fol owed-up for 6-18 months, averaged 9 months. The Oswestry disability index, intervertebral distance of the upper adjacent segments, deformation index of the upper adjacent vertebral body, concave angle of the fixed lumbar vertebrae superior end-plate and the upper adjacent vertebral body inferior end-plate, and Cobb angle were measured before operation, at 3 days postoperation and during final fol ow-up. RESULTS AND CONCLUSION:The Oswestry disability index of the final fol ow-up in the three groups were decreased when compared with that before operation (P0.05). This showed that in posterior spinal fixation operation, there was no significant difference in the early and medium-term subjective effect between addition of bone cement or not and different adding ways, and addition of bone cement or not and different adding ways could remarkably improve the life quality of the patients. The change of Cobb angle of fixed lumbar vertebrae between the final fol ow-up and 3 days after operation in conventional pedicle screw+bone cement group and novel perfusional pedicle screw+bone cement group was both less than that in the

  18. Biomechanics of cortical bone allografts among different fixation modes%异体皮质骨板不同固定方式的生物力学比较

    Institute of Scientific and Technical Information of China (English)

    张仁明; 廖瑛; 李宝兴; 余黎明

    2008-01-01

    BACKGROUND:The materials for internal fixation of bone allografts have been used in the clinic.However,they are only used in the regions bearing little stress because of low strength.The focus of current studies is how to enhance the fixation strength of the materials to expand application range.OBJECTIVE:To compare the strength difference of cortical bone allografts among different fixation modes and to investigate the possible mechanisms of action.DESIGN,TIME AND SETTING:An in vitro biomechanical experiment was performed at the Laboratory of Biomechanics,Nanhua University between October 2005 and March 2006.MATERIALS:Twenty-seven pieces of cadaveric femurs were included in this study.A total of 45 cortical bone allografts with a size of 110 mm×10 mm×3 mm and 90 bone screws were also used.METHODS:Twenty-seven femurs were made into simulated fracture models and randomized to 3 groups,with 9 models per group:A,B,and C.In the group A,the models were fixed with two cortical bone all6grafts; the models from the groups B and C were fixed with two bone allografts plus 5 bone screws and one bone allograft plus 5 bone screws accordingly.MAIN OUTCOME MEASURES:Biomechanical tests were performed in the above-mentioned 3 groups to measure compressive,bending and torsional stiffness as well as the maximum loads.RESULTS:Different fixation models displayed different mechanical characteristics.The group A exhibited similar compressive stiffness compared to the group B,but the level was significantly higher compared to the group C (P < 0.05).The other two stiffness parameters including bending and torsion were significantly greater in the group A than in the groups B and C (P < 0.05).The maximum loads of compression,bending,and torsion were significantly greater in the group A compared to the group B (P < 0.05) and group C (P < 0.01).CONCLUSION:The strength of bone allograft is highly related to fixation mode. The two bone allografts showed greater strength and stiffness

  19. 骨水泥和纳米骨浆强化椎弓根螺钉植入固定骨质疏松椎体的生物力学特点%Bone cement and nano bone putty strengthen pedicle screw implantation in the fixation of osteoporotic vertebral body:biomechanical characteristics

    Institute of Scientific and Technical Information of China (English)

    卢小兵; 孟祥翔

    2015-01-01

    BACKGROUND:Nano bone putty and bone cement injection are two common methods to strengthen the fixation of pedicle screws, but there are relatively few reports on the comparison of their strengthening effects. OBJECTIVE:To compare the biomechanical characteristics of bone cement and nano bone putty strengthening pedicle screw implantation in the fixation of osteoporotic vertebral body. METHODS: Totaly 24 human cadaveric pedicles were obtained, which were al in line with osteoporosis standards, and randomly divided into 3 groups: control group (only implanted pedicle screws), bone cement group (first injected bone cement in the nail channel, and then implanted pedicle screws) and nano bone putty group (first injected nano bone putty in the nail channel, and then implanted pedicle screws). After 2 hours of implantation, the maximum axial pulout strength and the maximum rotation torque of specimens in each group were determined. RESULTS AND CONCLUSION:The maximum axial pulout strength and maximum rotation torque of the bone cement and the nano bone putty groups were greater than those of the control group (P < 0.05), and the maximum axial pulout strength and the maximum rotation torque of the bone cement group were greater than those of the nano bone putty group (P < 0.05). These results demonstrate that the maximum axial pulout strength and the maximum rotation torque of pedicle screw implantation in the fixation of osteoporotic vertebral body can be effectively improved by injection of bone cement and nano bone putty, and the strengthening effect of bone cement is more obvious. %背景:纳米骨浆和骨水泥注入是强化椎弓根螺钉固定的两种常用方法,但目前关于两种加强方法的强化效果比较的报道相对较少。目的:对比骨水泥或纳米骨浆强化椎弓根螺钉植入固定骨质疏松椎体的生物力学特点。方法:取24个人尸体椎弓根,均符合骨质疏松标准,随机均分为3组,对照组仅植

  20. Peri-implant tissue response and biodegradation performance of a Mg-1.0Ca-0.5Sr alloy in rat tibia.

    Science.gov (United States)

    Berglund, Ida S; Jacobs, Brittany Y; Allen, Kyle D; Kim, Stanley E; Pozzi, Antonio; Allen, Josephine B; Manuel, Michele V

    2016-05-01

    Biodegradable magnesium (Mg) alloys combine the advantages of traditional metallic implants and biodegradable polymers, having high strength, low density, and a stiffness ideal for bone fracture fixation. A recently developed Mg-Ca-Sr alloy potentially possesses advantageous characteristics over other Mg alloys, such as slower degradation rates and minimal toxicity. In this study, the biocompatibility of this Mg-Ca-Sr alloy was investigated in a rat pin-placement model. Cylindrical pins were inserted in the proximal tibial metaphyses in pre-drilled holes orthogonal to the tibial axis. Implant and bone morphologies were investigated using μCT at 1, 3, and 6weeks after implant placement. At the same time points, the surrounding tissue was evaluated using H&E, TRAP and Goldner's trichrome staining. Although gas bubbles were observed around the degrading implant at early time points, the bone remained intact with no evidence of microfracture. Principle findings also include new bone formation in the area of the implant, suggesting that the alloy is a promising candidate for biodegradable orthopedic implants. PMID:26952400

  1. Biological fixation in anterior cruciate ligament surgery

    Directory of Open Access Journals (Sweden)

    Chih-Hwa Chen

    2014-04-01

    Full Text Available Successful anterior cruciate ligament (ACL reconstruction with tendon graft requires extensive tendon-to-bone healing in the bone tunnels and progressive graft ligamentization for biological, structural, and functional recovery of the ACL. Improvement in graft-to-bone healing is crucial for facilitating early, aggressive rehabilitation after surgery to ensure an early return to pre-injury activity levels. The use of various biomaterials for enhancing the healing of tendon grafts in bone tunnels has been developed. With the biological enhancement of tendon-to-bone healing, biological fixation of the tendon graft in the tunnel can be achieved in ACL reconstruction.

  2. Optimizing Stability in Femoral Neck Fracture Fixation.

    Science.gov (United States)

    Ye, Ye; Hao, Jiandong; Mauffrey, Cyril; Hammerberg, E Mark; Stahel, Philip F; Hak, David J

    2015-10-01

    Optimizing stability of femoral neck fracture fixation is important in obtaining a successful outcome. The mechanical problems and strategies for achieving optimal stability differ depending on patients' age and degree of osteoporosis. Femoral neck fractures in younger adults usually result from high-energy trauma and have a vertical fracture pattern. Strategies for optimizing fixation stability in this group include placing additional screws at right angles to the fracture plane and medial buttress plate augmentation. In elderly patients, screw position relative to the intact cortical femoral neck bone is of critical importance. Additional strategies for optimizing fixation stability in this group include the concept of length stable fixation, use of adjunctive calcium phosphate cement, and use of novel fixed angle fixation implants. PMID:26488776

  3. Management of subtrochanteric femur fractures with internal fixation and recombinant human bone morphogenetic protein-7 in a patient with osteopetrosis: a case report

    Directory of Open Access Journals (Sweden)

    Golden Robert D

    2010-05-01

    Full Text Available Abstract Introduction Osteopetrosis is a group of conditions characterized by defects in the osteoclastic function of the bone resulting in defective bone resorption. Clinically, the condition is characterized by a dense, sclerotic, deformed bone which, despite an increased density observable by radiography, often results in an increased propensity to fracture and delayed union. Case Presentation We report the case of a 27-year-old Asian man presenting with bilateral subtrochanteric femur fractures. He had a displaced right subtrochanteric femur fracture after a low-energy fall, which was treated surgically. The second fracture that our patient endured was diagnosed as a stress fracture ten weeks later when he complained of pain in the contralateral left thigh. By that time, the right-sided fracture exhibited no radiographic evidence of healing, and when the left-sided stress fracture was being treated surgically, bone grafting with recombinant human bone morphogenetic protein-7 was also performed on the right side. Conclusion While there are no data supporting the use of bone morphogenic proteins in the management of delayed healing in patients with osteopetrosis, no other reliable osteoinductive grafting options are available to treat this condition. Both fractures in our patient healed, but based on the serial radiographic assessment it is uncertain to what degree the recombinant human bone morphogenetic protein-7 may have contributed to the successful outcome. It may have also contributed to the formation of heterotopic bone around the fracture site. Further investigation of the effectiveness and indications of bone morphogenic protein use for the management of delayed fracture healing in patients with osteopetrosis is warranted.

  4. Study on rehabilitative exercise for patients with long bone comminuted fractures of lower limbs after operation of external fixation combined with auto-graft bone implantation%下肢长骨粉碎性骨折进行髓腔内自体骨支撑并外固定后的康复治疗

    Institute of Scientific and Technical Information of China (English)

    石蛟; 刘殿梅; 曹国恒; 司志军

    2012-01-01

    Objective To study the effect of early rehabilitative exercise for patients with long bone comminuted fractures of lower limbs after operation of external fixation combined with auto - graft bone implantation. Methods Twelve patients with long bone comminuted fractures of lower limbs were allocated into this study. After operation by using external fixation combined with auto - graft bone implantation, early rehabilitative exercise had been applied to reinforce the strength of muscles in lower limbs and range of movement ( ROM ) in knees of these patients. After treatment for 12 months, the strength of muscles in lower limbs and ROM in knees were assessed for evaluating the effect of treatment. Results After rehabilitative therapy for 12 months, all patients obtained their normal muscle strength of lower limbs and ROM in knees. Conclusion Early rehabilitative therapy is an efficient method to improve activities of daily living for patients with long bone comminuted fractures of lower limbs after operation of external fixation combined with auto - graft bone implantation.%目的 探讨下肢长骨粉碎性骨折患者进行髓腔内自体骨支撑并外固定支架固定术后早期患肢进行康复训练的疗效.方法 对12例下肢长骨粉碎性骨折采用髓腔内自体骨支撑并外固定支架固定,术后1~3天采用镇痛、早期运动疗法及主、被动关节功能练习等综合康复锻炼.结果 12例经有效康复治疗关节的活动度达到生理要求,肌肉萎缩程度明显减轻.结论 下肢长骨粉碎性骨折进行髓腔内自体骨支撑并外固定支架固定术后早期康复治疗是保证肢体早期功能恢复的有效方法.

  5. Biomechanical analysis of fracture fixation with external fixator in vivo

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To investigate the different ways of measuring the main axial strain during treatment with an external fixator and to find the suitable compression loaded by the external fixator at an early stage.Methods: Eighteen healthy big-ear rabbits were randomly divided into two groups according to different measuring methods: Group A and Group B. In Group A,a strain gauge was affixed to the external tibial cortex with 502 glue, and in Group B, a bone cement-coated strain gauge was installed on the internal tibial cortex. Groups A and B were divided into two subgroups A1, A2 and B1,B2, respectively, according to the pressure of half of and the same as the body weight. A Z-shaped left mid-shaft tibial osteotomy was performed and fixed by an external fixator. Results: The scaler curves of Group A changed dramatically during the early stage. The trendlines of the internal and external cortex went consistently after reaching the stable stage while the latter strain value was higher than the former. The time for Group B reaching the stable stage was short, but its absolute strain value was less than that of Group A. Before they were pressed to the stable stage, the declined speed of Subgroup A1 was more slowly than that of Subgroup A2 while the results of Subgroups B1 and B2 were same. Group A had an ascending trend after it declined while Group B didn't have. After they reached the stable stage, both Subgroups A1 and A2 had a declining trend while Subgroup A2 was more quickly than Subgroup Al, Subgroup B1 was kept at a definite level while Subgroup B2 fluctuated.Conclusions: The axial strain under external fixator can be measured by bone cement coated-strain gauge in vivo. The data may suggest that half of the body weight load was suitable for external fixator.

  6. Evaluations of guided bone regeneration in canine radius segmental defects using autologous periosteum combined with fascia lata under stable external fixation

    OpenAIRE

    Yu, Zhe; Geng, Jie; Gao, Haoran; Zhao, Xinwen; Chen, Jingyuan

    2014-01-01

    Background Although bone defect is one of the most common orthopaedic diseases, treatment remains a challenge and an issue of debate. Guided bone regeneration (GBR) is primarily accompanied by barrier membranes; however, optional membranes show some inherent flaws in clinical application. The purpose of this study was to observe the healing velocity and quality of repairing canine radius segmental defect using transferred autologous periosteum combined with fascia lata, which can provide bett...

  7. The clinical effects of osteoporosis of lumbar degenerative disease by injectable calcium sulfate bone cement to strengthen pedicle screw internal fixation%骨质疏松腰椎退行性疾病的手术治疗分析

    Institute of Scientific and Technical Information of China (English)

    孔祥瑞; 刘德政; 刘海峰; 杨计策; 赵志超

    2015-01-01

    ObjectiveTo explore the clinical effects of osteoporosis of lumbar degenerative disease by injectable calcium sulfate bone cement to strengthen pedicle screw internal fixation. Methods 82 cases of patients with lumbar degenerative dis-ease of osteoporosis word randomly divided into experiment group(41 cases) and control group(41 cases). The control group were treated by transpedicle screws fixation, the experiment group were treated by injectable calcium sulfate bone cement to strengthen pedicle screw internal fixation. The time of operation, mean bleeding volum, the scores of VAS, ODI, JOA were com-pared for the two groups. ResultsThe time of operation, mean bleeding volum for the experiment group were better than the control group; There was no significant difference on the scores of VAS, ODI, JOA; The scores of VAS, ODI for the experiment group were lower than the control group postoperation for 1 week, 2 months, 12 months; The scores of JOA for the experiment group were higher than the control group postoperation for 1 week, 2 months, 12 months. ConclusionIt can improve the scores of VAS, ODI, JOA for the patients with osteoporosis of lumbar degenerative disease by injectable calcium sulfate bone cement to strengthen pedicle screw internal fixation. It is worthy of clinical promotion.%目的:探讨可注射硫酸钙骨水泥强化椎弓根钉内固定治疗骨质疏松腰椎退行性疾病的临床疗效。方法:按照随机数字表法将我院收治的82例骨质疏松腰椎退行性疾病患者均分为实验组和对照组,对照组给予单纯椎弓根内固定治疗,实验组给予可注射硫酸钙骨水泥强化椎弓根钉内固定治疗。比较两组患者手术时间、术中出血量以及治疗前后疼痛视觉模拟评分(VAS)、Oswestry 功能障碍指数(ODI)、JOA 腰椎病疗效评分变化情况。结果:实验组患者手术时间和术中出血量显著高于对照组;两组患者术前 VAS 评分、ODI 评分、JOA

  8. Enhancement of biodegradation and osseointegration of poly(ε-caprolactone)/calcium phosphate ceramic composite screws for osteofixation using calcium sulfate.

    Science.gov (United States)

    Wu, Chang-Chin; Hsu, Li-Ho; Tsai, Yuh-Feng; Sumi, Shoichiro; Yang, Kai-Chiang

    2016-04-01

    Internal fixation devices, which can stabilize and realign fractured bone, are widely used in fracture management. In this paper, a biodegradable composite fixator, composed of poly(ε-caprolactone), calcium phosphate ceramic and calcium sulfate (PCL/CPC/CS), is developed. The composition of CS, which has a high dissolution rate, was expected to create a porous structure to improve osteofixation to the composite fixator. PCL, PCL/CPC, and PCL/CPC/CS samples were prepared and their physical properties were characterized in vitro. In vivo performance of the composite screws was verified in the distal femurs of rabbits. Results showed that the PCL/CPC/CS composite had a higher compressive strength (28.55 ± 3.32 MPa) in comparison with that of PCL (20.64 ± 1.81 MPa) (p enhanced apatite formation of the PCL/CPC composite screw. This osteoconductive PCL/CPC/CS is a good candidate material for internal fixation devices. PMID:27041468

  9. Results of screw fixation combined with cortical drilling for treatment of dorsal cortical stress fractures of the third metacarpal bone in 56 Thoroughbred racehorses

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate screw fixation with cortical drilling as a surgical treatment for dorsal cortical stress fractures of MCIII in the Thoroughbred racehorse. Details of age, sex, limb affected, fracture assessment, and post operative recommendations were obtained from medical records and radiographs. Fracture healing was assessed radiographically at the time of screw removal. Performance evaluation was determined from race records obtained from The Jockey Club Information System, Lexington, Kentucky. Fifty-six Thoroughbred racehorses were treated surgically for stress fracture of MCIII with screw fixation and cortical drilling. Stress fractures occurred primarily in the left front limb of the male 3-year-olds, in the dorsolateral cortex of the middle third of MCIII. Ninety-seven percent of the fractures travelled in a dorsodistal to palmaroproximal direction. Median period to screw removal was 2.0 months. Evaluation at time of screw removal revealed 98% of single stress fractures of the left front limb were healed radiographically. Median period to resume training was 2.75 months (single stress fractures); median period to race was 7.62 months. There was no statistically significant difference in earnings/start before and after surgical intervention. Of the 63 fractures treated, two recurred. There were no catastrophic failures, and no incisional infections

  10. Biomechanical analysis of lumbosacral fixation.

    Science.gov (United States)

    McCord, D H; Cunningham, B W; Shono, Y; Myers, J J; McAfee, P C

    1992-08-01

    Flexion testing was performed until failure on 66 lumbosacral bovine spinal segments comparing ten different lumbosacral instrumentation techniques. Maximum flexion moment at failure, flexural stiffness, and maximum angulation of the lumbosacral joint at failure were determined as well as strain measurements across the anterior aspect of the lumbosacral intervertebral disc using an extensometer. The maximum moment at failure was significantly greater for the only two devices that extended fixation into the ilium anterior to the projected image of the middle osteoligamentous column: ISOLA Galveston and ISOLA iliac screws (F = 12.2, P less than 0.001). The maximum stiffness at failure reinforced these findings (F = 23.7, P less than 0.001). A second subset of stability showed the advantages of S2 pedicle fixation by increasing the flexural lever arm (Cotrel-Dubousset butterfly plate, and Cotrel-Dubousset Chopin block, P less than 0.05). This exhaustive in vitro biomechanical study introduces the concept of a pivot point at the lumbosacral joint at the intersection of the middle osteoligamentous column (sagittal plane) and the lumbosacral intervertebral disc (transverse plane). A spinal surgeon can increase the stability of lumbosacral instrumentation by extending fixation through the anterior sacral cortex (Steffee plate group with pedicle screws that medially converge in a triangular fashion). A means of enhancing this fixation was to achieve more inferior purchase by extending the fixation down to the S2 pedicle (Cotrel-Dubousset Chopin and Cotrel-Dubousset butterfly groups). However, the best fixation was achieved by obtaining purchase between the iliac cortices down into the superior acetabular bone.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1523506

  11. One-stage posterior debridement, bone grafting and internal fixation for thoracolumbar spinal tuberculosis%一期后路病灶清除植骨融合内固定治疗胸腰椎结核

    Institute of Scientific and Technical Information of China (English)

    任之强; 丁金勇; 晋大祥; 庄洪; 万梓成

    2014-01-01

    Objective To evaluate the clinical efficacy of one-stage posterior debridement, bone grafting and internal fixation for thoracolumbar spinal tuberculosis.Methods From January 2010 to June 2012,28 patients with thoracolumbar spinal tuberculosis undergoing one-stage posterior debridement, bone grafting and internal fixation procedure were reviewed retrospectively .All cases were followed up.The kyphosis Cobb’s angle, erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), bone fusion and American Spinal Injury Association (ASIA) grade before and after surgery were reviewed and compared.Results The median peri-od of follow-up was 1.2 years.There was no significant loss of kyphosis Cobb’s angle after operation.The average kyphosis Cobb’s angle was corrected 4.12 °, the average correction rate was 24.5%.The ESR and CRP levels returned to normal at final follow-up. The majority of bony fusion was achieved within 7.8 months.Most of the original symptoms disappeared.According to ASIA grade, the neurological function was improved after operation.Conclusion Treatments with one-stage posterior debridement, bone grafting and internal fixation for thoracolumbar spinal tuberculosis can effectively achieve debridement, spinal cord decompression, correc-tion of spinal kyphosis, reconstruction of spinal stability.%目的:探讨一期后路病灶清除植骨融合内固定治疗胸腰椎结核的临床疗效。方法回顾性分析2010年1月~2012年6月本院采用一期后路病灶清除植骨融合内固定治疗的28例胸腰椎结核患者的临床资料,对比研究患者手术前后患椎后凸Cobb角、红细胞沉降率( erythrocyte sedimentation rate, ESR)、C 反应蛋白( C-reaction protein, CRP)、植骨融合及美国脊髓损伤协会( American Spinal Injury Association, ASIA)分级变化情况。结果28例获得随访,平均随访1.2年,术后Cobb角无明显丢失,后凸畸形平均纠正4.12°,平均矫正率24

  12. 骨水泥强化治疗骨质疏松症伴脊柱侧弯疗效分析%Effects of pedicle screw fixation with bone cement tract augmentation on scoliolosis accompanying osteoporosis

    Institute of Scientific and Technical Information of China (English)

    丁金勇; 洪少勇; 晋大祥; 梁德; 江晓兵

    2012-01-01

    目的 探讨对伴骨质疏松症的退行性脊柱侧弯病人行后路减压、骨水泥强化钉道椎弓根内固定融合治疗的临床疗效.方法 2006-10-2009-07收治伴骨质疏松症的退变性脊柱侧弯患者18例,女11例,男7例,平均年龄64.5岁,均冠状面畸形,Cobb's角>15°或合并椎体旋转半脱位以及合并椎体骨质疏松性病理性骨折.手术采取部分椎板切除,松解神经根以充分减压,骨水泥强化钉道的椎弓根长节段钉棒系统进行矫形,记录手术前后Cobb's角、前凸角,手术前后进行ODI评分.结果 所有病例切口均Ⅰ期愈合,无感染或深静脉血栓等近期并发症;进行24~54个月随访(平均36个月),未出现断钉、断棒,及椎弓根钉拔出、松动、融合节段假关节形成或感染等远期并发症.患者术后冠状面Cobb's角均低于术前(P<0.05),腰椎矢状面前凸角均高于术前(P<0.05),ODI综合评分均低于术前(P<0.05).结论 在充分减压消除症状的基础上,用骨水泥强化钉道进行侧弯的矫形,可以获得脊柱平衡并能够避免矫形的丢失.%Objective To evaluate the clinical effect of the treatment that part or full laminecto-my and correction with posterior long segment pedicle screw/rod internal fixation system by augmentation and restoration with bone cement in the screw tract and posterolateral or intervertebral spinal fusion, about degenerative scoliolosis accompanying with osteoporosis. Methods Eighteen patients, 11 females and 7 males (average age of 643 years),with degenerative scoliosis accompanying by osteoporosis were selected from our hospital, between October 2006 and July 2009. The patients were treated with part or full laminectomy and posterior long segment pedicle screw/rod internal fixation system by augmentation and restoration with bone cement in the screw tract and posterolateral or intervertebral spinal fusion. Result All cases were followed up for 36 months (range 24-54 months). No

  13. Suture anchor fixation strength with or without augmentation in osteopenic and severely osteoporotic bones in rotator cuff repair: a biomechanical study on polyurethane foam model

    OpenAIRE

    Er, Mehmet Serhan; Altinel, Levent; Eroglu, Mehmet; Verim, Ozgur; Demir, Teyfik; Atmaca, Halil

    2014-01-01

    Background The purpose of the present study was to compare the results of various types of anchor applications with or without augmentation in both osteopenic and severely osteoporotic bone models. Methods Two different types of suture anchors were tested in severely osteoporotic (SOP) and osteopenic polyurethane (PU) foam blocks using an established protocol. An Instron machine applied static loading parallel to the axis of insertion until failure, and the mean anchor failure strengths were ...

  14. Ureteral injury after posterior lumbar discectomy with interbody screw fixation

    OpenAIRE

    Pillai, Sunil Bhaskara; Hegde, Padmaraj; Venkatesh, Giridhar; Iyyan, Bhalaguru

    2013-01-01

    We report a case of iatrogenic ureteral injury secondary to L5 laminectomy and microdiscectomy with L5–S1 bone graft with posterior lumbar interbodyfusion using presacral cancellous screw fixation, managed by initial ureteral stent placement and subsequent Boari bladder flap repair. A 33-year-old woman underwent L5 laminectomy and microdiscectomy with L5–S1 bone graft with posterior lumbar interbody fusion using presacral cancellous screw fixation. On postoperative day 10, she developed lower...

  15. Surgical treatment of the osteoporotic spine with bone cement-injectable cannulated pedicle screw fixation: technical description and preliminary application in 43 patients

    Directory of Open Access Journals (Sweden)

    Fei Dai

    2015-02-01

    Full Text Available OBJECTIVES: To describe a new approach for the application of polymethylmethacrylate augmentation of bone cement-injectable cannulated pedicle screws. METHODS: Between June 2010 and February 2013, 43 patients with degenerative spinal disease and osteoporosis (T-score <-2.5 underwent lumbar fusion using cement-injectable cannulated pedicle screws. Clinical outcomes were evaluated using a Visual Analog Scale and the Oswestry Disability Index. Patients were given radiographic follow-up examinations after 3, 6, and 12 months and once per year thereafter. RESULTS: All patients were followed for a mean of 15.7±5.6 months (range, 6 to 35 months. The Visual Analog Scale and Oswestry Disability Index scores showed a significant reduction in back pain (p = 0.018 and an improvement in lower extremity function (p = 0.025 in patients who underwent lumbar fusion using the novel screw. Intraoperative cement leakage occurred in four patients, but no neurological complications were observed. Radiological observation indicated no loosening or pulling out of the novel screw, and bone fusion was excellent. CONCLUSIONS: The described polymethylmethacrylate augmentation technique using bone cement-injectable cannulated pedicle screws can reduce pain and improve spinal dysfunction in osteoporotic patients undergoing osteoporotic spine surgery.

  16. Transpedicular vertebral body augmentation reinforced with pedicle screw fixation in fresh traumatic A2 and A3 lumbar fractures: comparison between two devices and two bone cements.

    Science.gov (United States)

    Korovessis, Panagiotis; Vardakastanis, Konstantinos; Repantis, Thomas; Vitsas, Vasilios

    2014-07-01

    This retrospective study compares efficacy and safety of balloon kyphoplasty (BK) with calcium phosphate (Group A) versus KIVA implant with PMMA (Group B) reinforced with three vertebrae pedicle screw constructs for A2 and A3 single fresh non-osteoporotic lumbar (L1-L4) fractures in 38 consecutive age- and diagnosis-matched patient populations. Extracanal leakage of both low-viscosity PMMA and calcium phosphate (CP) as well as the following roentgenographic parameters: segmental kyphosis (SKA), anterior (AVBHr) and posterior (PVBHr) vertebral body height ratio, spinal canal encroachment (SCE) clearance, and functional outcome measures: VAS and SF-36, were recorded and compared between the two groups. All patients in both groups were followed for a minimum 26 (Group A) and 25 (Group B) months. Extracanal CP and PMMA leakage was observed in four (18 %) and three (15 %) vertebrae/patients of group A and B, respectively. Hybrid fixation improved AVBHr, SKA, SCE, but PVBHr only in group B. VAS and SF-36 improved postoperatively in the patients of both groups. Short-segment construct with the novel KIVA implant restored better than BK-fractured lumbar vertebral body, but this had no impact in functional outcome. Since there was no leakage difference between PMMA and calcium phosphate and no short-term adverse related to PMMA use were observed, we advice the use of PMMA in fresh traumatic lumbar fractures. PMID:23982115

  17. Complicaciones de los tornillos de bloqueo intermaxilar en el tratamiento de las fracturas mandibulares Complications of self-tapping bone screws for maxillomandibular fixation in the treatment of jaw fracture

    Directory of Open Access Journals (Sweden)

    J. Molina Montes

    2008-08-01

    Full Text Available Durante la última década se ha introducido el tornillo de bloqueo intermaxilar como método de fijación maxilomandibular en el tratamiento de las fracturas de mandíbula. El propósito del estudio es evaluar las complicaciones de la técnica y la yatrogenia dental que derivan de su aplicación durante un periodo de 4 años. Se han revisado un total de 62 pacientes y 272 tornillos y, aunque han aparecido complicaciones, su incidencia es baja.In the last decade, self-tapping bone screws have been used widely as a temporary maxillomandibular fixation method in the treatment of jaw fractures. The purpose of the present study was to evaluate the complications of the technique and potential dental iatrogenesis over a period of 4 years. We reviewed a total of 62 patients and 272 screws. Although complications appeared, the complication rate was low.

  18. THE FUNCTIONAL OUTCOME OF MANAGEMENT OF SCHATZKER TYPE II AND III TIBIAL PLATEAU FRACTURES TREATED WITH INDIRECT ELEVATION, PERCUTANEOUS FIXATION AND BONE GRAFTING

    Directory of Open Access Journals (Sweden)

    Sheshagiri

    2016-02-01

    Full Text Available INTRODUCTION Damage to the joint is more extensive in tibia plateau fractures than the roentgenograms Indicate. It may be associated with soft tissue trauma, ligament injuries (4-33% medial Collateral ligament being the most common, meniscal injuries (20%, lateral collateral Ligament injury (3%, peroneal nerve injuries (3%. Posttraumatic arthritis is associated with residual instability or axial malalignment rather than joint depression. So we use minimally invasive approach to the depressed tibial plateau fractures (Schatzker type II & III. MATERIALS AND METHODS 32 patients were studied. They were followed up for maximum of 3yrs and a minimum of 1.5yrs with an average of 2.2yrs. Inclusion criteria included those patients with an age group between 20yrs and 60yrs, joint depression more than 3mm. Patients with open fracture, severe osteoporotic bones and with radiographic evidence of osteoarthritis are excluded from the study. CT was done in all patients. Mean age group was 28.8yrs and 19(76% were males; the mean articular depression was 11.32 mm measured in CT. Pre-op evaluation includes x-rays of the knee, stress x-rays if needed, and CT was done with 2mm limited cuts. Cancellous Bone graft was taken from opposite tibia through a 3-4cm long incision made below the tibial tuberosity over the medial aspect of the tibia. Cortical window was made in the affected limb, just enough to introduce the punch, and its position was confirmed under c-arm and depressed fragment was elevated with punch and reduction was held with k wires in subarticular plane and later two cannulated cancellous screws was introduced and the defect packed with bone grafts, Post-operatively all patients were immobilized with plaster of Paris (POP for 3 weeks and then mobilized. RESULTS The mean duration of the follow up was 2.2yrs. Results were excellent in 21 patients (84%, good 3(12% and fair in 1 patients (4% according to anatomic and functional criteria by Hohl and Luck

  19. Self-assembled Biodegradable Nanoparticles and Polysaccharides as Biomimetic ECM Nanostructures for the Synergistic effect of RGD and BMP-2 on Bone Formation.

    Science.gov (United States)

    Wang, Zhenming; Dong, Li; Han, Lu; Wang, Kefeng; Lu, Xiong; Fang, Liming; Qu, Shuxin; Chan, Chun Wai

    2016-01-01

    Producing biomimetic extracellular matrix (ECM) is an effective approach to improve biocompatibility of medical devices. In this study, biomimetic ECM nanostructures are constructed through layer-by-layer self-assembling positively charged chitosan (Chi), negatively charged oxidized sodium alginate (OAlg), and positively charged bovine serum albumin (BSA)-based nanoparticles. The BSA-based nanoparticles in the self-assembled films not only result in porous nanostructures similar to natural ECM, but also preserve the activity and realize the sustained release of Bone morphogenetic protein-2 (BMP-2). The results of bone marrow stem cells (BMSCs) culture demonstrate that the penta-peptide glycine-arginine-glycine-aspartate-serine (GRGDS) grafted Chi/OAlg films favor cell adhesion and proliferation. GRGDS and BMP-2 in biomimetic ECM nanostructures synergistically promote BMSC functions and new bone formation. The RGD and BMP incorporated biomimetic ECM coatings could be applied on a variety of biomedical devices to improve the bioactivity and biocompatibility. PMID:27121121

  20. Self-assembled Biodegradable Nanoparticles and Polysaccharides as Biomimetic ECM Nanostructures for the Synergistic effect of RGD and BMP-2 on Bone Formation

    Science.gov (United States)

    Wang, Zhenming; Dong, Li; Han, Lu; Wang, Kefeng; Lu, Xiong; Fang, Liming; Qu, Shuxin; Chan, Chun Wai

    2016-01-01

    Producing biomimetic extracellular matrix (ECM) is an effective approach to improve biocompatibility of medical devices. In this study, biomimetic ECM nanostructures are constructed through layer-by-layer self-assembling positively charged chitosan (Chi), negatively charged oxidized sodium alginate (OAlg), and positively charged bovine serum albumin (BSA)-based nanoparticles. The BSA-based nanoparticles in the self-assembled films not only result in porous nanostructures similar to natural ECM, but also preserve the activity and realize the sustained release of Bone morphogenetic protein-2 (BMP-2). The results of bone marrow stem cells (BMSCs) culture demonstrate that the penta-peptide glycine-arginine-glycine-aspartate-serine (GRGDS) grafted Chi/OAlg films favor cell adhesion and proliferation. GRGDS and BMP-2 in biomimetic ECM nanostructures synergistically promote BMSC functions and new bone formation. The RGD and BMP incorporated biomimetic ECM coatings could be applied on a variety of biomedical devices to improve the bioactivity and biocompatibility. PMID:27121121

  1. Fixation of distal radius fractures in adults: a review.

    Science.gov (United States)

    Obert, L; Rey, P-B; Uhring, J; Gasse, N; Rochet, S; Lepage, D; Serre, A; Garbuio, P

    2013-04-01

    In patients for whom function is a priority, anatomic reduction and stable fixation are prerequisites for good outcomes. Several therapeutic options exist, including orthopedic treatment and internal fixation with pins (intra- and extrafocal), external fixation which may or may not bridge the wrist, and different internal fixation techniques with dorsal or palmar plates using or not, locking screws. Arthroscopy may be necessary in case of articular fracture. In the presence of significant metaphyseal bone defects, filling of the comminution with phosphocalcic cements provides better graft stability. The level of evidence is too low to allow recommending one type of fixation for one type of fracture; and different fixation options to achieve stable reduction exist, each with its own specific complications. With the new generations of palmar plate, secondary displacement is becoming a thing of the past. PMID:23518070

  2. Experimental and Numerical Modeling of Screws Used for Rigid Internal Fixation of Mandibular Fractures

    OpenAIRE

    Naresh Chaudhary; Lovald, Scott T.; Jon Wagner; Tariq Khraishi; Bret Baack

    2008-01-01

    Experimental and numerical methods are used to explore the stresses generated around bone screws used in rigid internal fixation of mandibular fractures. These results are intended to aid in decisions concerning both the design and the use of these bone screws. A finite element (FE) model of a human mandible is created with a fixated fracture in the parasymphyseal region. The mandibular model is anatomically loaded, and the forces exerted by the fixation plate onto the simplified screws are o...

  3. Correção de falhas ósseas diafisárias: trasnporte ósseo fixado com placa Corretive procedure in diaphyseal bone gaps: bone trasnpot fixated with plate

    Directory of Open Access Journals (Sweden)

    Celso Hermínio Ferraz Picado

    2007-01-01

    Full Text Available O objetivo deste estudo é descrever um novo sistema de transporte ósseo que dispensa o uso de fios transfixantes. O sistema, constituído por uma placa, um carro móvel e por um dispositivo tracionador, foi instalado na tíbia direita de 17 ovelhas para preencher um defeito ósseo de 1 cm. O transporte ósseo foi iniciado 7 dias após a cirurgia numa taxa de 0,8 mm/dia, dividido em 0,2 mm a cada 6 horas. Radiografias em ântero-posterior e perfil foram realizadas imediatamente após a cirurgia e semanalmente até o término do transporte. Em todos os 12 animais que completaram o estudo, o defeito ósseo foi preenchido com formação do regenerado e consolidação do foco alvo. O estudo demonstra que o sistema aqui apresentado realiza o transporte ósseo de maneira efetiva, eliminando o uso de fios ou pinos transfixantes.The objective of this study is to describe a new bone transport system not requiring the use of transfixating wires. The system, which is constituted by a plate, a movable conveyor and a hauling device, was set up on the right tibia of 17 sheep intending to fill a 1-cm bone gap. Bone transport started 7 days after surgery on a rate of 0.8 mm/day, divided into 0.2 mm at each 6 hours. X-ray images of anteroposterior and lateral planes were taken immediately after surgery and on a weekly basis until transport was finished. In all 12 animals completing the study, the bone gap was filled with regenerated formation and target focus consolidation. The study shows that the system presented here effectively performs bone transport, eliminating the use of transfixating wires or pins.

  4. Locking plate fixation for proximal humerus fractures.

    LENUS (Irish Health Repository)

    Burke, Neil G

    2012-02-01

    Locking plates are increasingly used to surgically treat proximal humerus fractures. Knowledge of the bone quality of the proximal humerus is important. Studies have shown the medial and dorsal aspects of the proximal humeral head to have the highest bone strength, and this should be exploited by fixation techniques, particularly in elderly patients with osteoporosis. The goals of surgery for proximal humeral fractures should involve minimal soft tissue dissection and achieve anatomic reduction of the head complex with sufficient stability to allow for early shoulder mobilization. This article reviews various treatment options, in particular locking plate fixation. Locking plate fixation is associated with a high complication rate, such as avascular necrosis (7.9%), screw cutout (11.6%), and revision surgery (13.7%). These complications are frequently due to the varus deformation of the humeral head. Strategic screw placement in the humeral head would minimize the possibility of loss of fracture reduction and potential hardware complications. Locking plate fixation is a good surgical option for the management of proximal humerus fractures. Complications can be avoided by using better bone stock and by careful screw placement in the humeral head.

  5. 腰椎内固定中两种椎弓根钉加强技术与骨水泥的应用%Two strengthening pedicle screw techniques and bone cement in lumbar internal fixation

    Institute of Scientific and Technical Information of China (English)

    江泽华; 朱如森; 袁建军; 邵高升; 张学利

    2013-01-01

    BACKGROUND:Screw loosening and shedding may occur after osteoporosis associated with lumbar degenerative disease treated with pedicle screw fixation. Application of pedicle screw enhanced with cured materials can improve the therapeutic effect. OBJECTIVE:To compare the clinical effect of pedicle screws enhanced with poly(methyl methacrylate) and injectable calcium sulfate cement in the lumbar internal fixation of osteoporosis. METHODS:Sixty-one patients diagnosed with osteoporosis combined with lumbar spondylolisthesis, lumbar spinal instability, and severe lumbar spinal stenosis were col ected. Al patients were divided into two groups according to the treatment method:poly(methyl methacrylate) bone cement enhanced pedicle screw group and calcium sulfate bone cement enhanced pedicle screw group. RESULTS AND CONCLUSION:There were no significant differences in the operation time, blood loss, preoperative and postoperative visual analog scale score, Japanese Orthopedic Association scores and the Japanese Orthopedic Association score improvement rate between two groups (P>0.05). The results showed that two patients had bone cement leakage in poly(methyl methacrylate) group which had no neurological symptoms caused by new symptoms during fol ow-up period. The bone mineral density was not improved gradual y in poly(methyl methacrylate) group with fol ow-up time prolonging;however, in calcium sulfate group, the bone mineral density was increased significantly after treatment, and the change of bone mineral density was linearly related with Japanese Orthopaedic Association score improvement rate in calcium sulfate group. No screw loosening, pul ing out or neurological dysfunction occurred in both groups. The results indicate that like poly(methyl methacrylate), balcium sulfate bone cement can increase the stability of pedicle screws.%背景:骨质疏松伴腰椎退行性病变行椎弓根钉固定骨质疏松的椎体后可能会出现螺钉的松动、脱落,使用

  6. Proceedings of biodegradation

    International Nuclear Information System (INIS)

    This book contains the proceedings of Biodegradation. Topics include:biodegradation using the tools of biotechnology, basic science aspects of biodegradation, the physiological characteristics of microorganisms, the use of selective techniques that enhance the process of microbial evolution of biodegradative genes in nature, the genetic characteristics of microorganisms allowing them to biodegrade both natural and synthetic toxic chemicals, the molecular techniques that allow selective assembly of genetic segments form a variety of bacterial strains to a single strain, and methods needed to advance biodegradation research as well as the high-priority chemical problems important to the Department of Defense or to the chemical industry

  7. A novel enzymatically-mediated drug delivery carrier for bone tissue engineering applications: combining biodegradable starch-based microparticles and differentiation agents

    OpenAIRE

    Balmayor, Elizabeth Rosado; Tuzlakoglu, K.; Marques, A.P.; Azevedo, Helena S.; Reis, R.L.

    2008-01-01

    In many biomedical applications, the performance of biomaterials depends largely on their degradation behavior. For instance, in drug delivery applications, the polymeric carrier should degrade under physiological conditions slowly releasing the encapsulated drug. The aim of this work was, therefore, to develop an enzymaticmediated degradation carrier system for the delivery of differentiation agents to be used in bone tissue engineering applications. For that, a polym...

  8. Mechanics research of bone cement augmentation on pedicle screw in revision of internal lumbar fixation%椎弓根螺钉骨水泥强化技术在腰椎内固定翻修手术中的力学研究

    Institute of Scientific and Technical Information of China (English)

    陈路; 廖琦; 龚玉琴

    2014-01-01

    目的:评价骨水泥强化技术在钉道扩大时对椎弓根螺钉固定强度的影响,为腰椎内固定翻修选择可靠的补救技术提供依据。方法选用成人尸体腰椎标本40个,观察组进行骨水泥强化,对照组普通方法置钉,进行生物力学检测。结果两种固定方法的最大轴向拔出力及最大旋出扭矩具有显著性差异(P<0.001),并提示弱相关。结论(1)在腰椎内固定翻修手术中,对椎弓根螺钉进行骨水泥强化可以有效提高椎弓根螺钉的固定强度。(2)钉道本身的骨质量对进行强化后的椎弓根螺钉固定强度影响有限。%Objective To evaluate the effect of bone cement augmentation technique on fixation strength of pedicle screw dur-ing trajectory expansion,to provide the basis of reliable remedial technique selection for revision of internal lumbar fixation.Methods A total of 40 lumbar vertebrae and 80 pedicles were obtained to stimulate the trajectory of pedicle needing revision after internal lumbar fixation surgery. 40 lumbar vertebrae were randomly divided into Group A and Group B ,with 20 simple fixed sides and 20 augmented fixed sides in each group. In Group A,pedicles on both sides of all the specimens were determined for the maximum axial pullout of strength;while in Group B,pedicles on both sides of all the specimens were detected for the maximum rotary torque,and differences between the two sides were compared. Results (1) There was significant difference between the two fixations,indicating a weak correlation. Conclusion (1)It was confirmed that in revision of internal lumbar fixation,bone cement augmentation on pedicle screw can effectively improve the strength of pedicle screw. (2)Maximum axial pullout of strength and maximum rotary torque in reinforced group were weakly correlated with those in the control group ,suggesting the bone quality of the trajectory had limited influence on the strength of reinforced pedicle screw

  9. Anterior plate internal fixation and autologous iliac bone graft fusion in the repair of thoracic spinal tuberculosis:bone healing%前路钢板置入内固定与自体髂骨植骨融合修复胸椎结核的骨愈合

    Institute of Scientific and Technical Information of China (English)

    黄江; 李小峰; 杨渊

    2014-01-01

    focus and achieve a good internal fixation, but this treatment needs to cut the rid. The surgeon discovered in years of clinical practice that distraction of intercostal space without cutting off the ribs could completely remove the focus and achieve fixation and fusion. OBJECTIVE:To explore the feasibility, advantages and disadvantages of anterior plate fixation and autologous bone graft fusion in the repair of thoracic spinal tuberculosis. METHODA total of 30 cases of thoracic spinal tuberculosis were enrol ed. On the base of traditional thoracic spinal anterior surgical approach, the rib was reserved. Anterior distraction device was used to open the ribs for clearance and to move the focus of thoracic spinal tuberculosis. Autologous ilium was obtained and subjected to fusion and anterior plate fixation. Visual Analog Scale, Oswestry Disability Index, Frankel grade and Bridwel bone healing rating were used before and after treatment. RESULTS AND CONCLUSION:A total of 30 patients were fol owed up for 3-60 months. The bone healing (class A) was seen, but no fistula formation was visible. Nerve compression symptoms were improved, without aggravating cases. Postoperatively, the average Cobb angle correction was 10.32°. After 6 months, imaging revealed bone fusion of affected vertebral body. After 18 months, the vertebral height was not lost obviously, no recurrence of vertebral tuberculosis. These results indicated that anterior intercostal space without cutting ribs exposed clearly, showing a large space, where can meet the requirement of first-stage debridement fixation and fusion in the repair of thoracic tuberculosis. The pathological changes were visibly clear;the focus was thoroughly removed, and the ribs were reserved. The outcomes are identical to rib resection. Simultaneously, autogenous iliac trilateral cortex has good supporting effects. Loose cancellous bone mesh has good osteogenesis and is helpful to bone healing.

  10. Long-term in vivo degradation behaviour and biocompatibility of the magnesium alloy ZEK100 for use as a biodegradable bone implant.

    Science.gov (United States)

    Dziuba, Dina; Meyer-Lindenberg, Andrea; Seitz, Jan Marten; Waizy, Hazibullah; Angrisani, Nina; Reifenrath, Janin

    2013-11-01

    Magnesium alloys are the focus of research as resorbable materials for osteosynthesis, as they provide sufficient stability and would make surgery to remove implants unnecessary. The new degradable magnesium alloy ZEK100 was developed to improve the stability and corrosion resistance by alloying with zinc, rare earth metals and zirconium. As the implants were degraded to only a limited extent after 6 months implantation in a previous in vivo study the present study was conducted to evaluate the long-term degradation behaviour and biocompatibility in the same animal model over 9 and 12 months. Five rabbits each with intramedullary tibia implants were examined over 9 and 12 months. Three legs were left without an implant to serve as negative controls. Numerous examinations were performed in the follow-up (clinical examinations, serum analysis, and radiographic and in vivo micro-CT investigations) and after death (ex vivo micro-CT, histology, and implant analysis) to assess the in vivo degradation and biocompatibility. It could be shown that favourable in vivo degradation behaviour is not necessarily associated with good biocompatibility. Although ZEK100 provided a very high initial stability and positive biodegradation, it must be excluded from further biomedical testing as it showed pathological effects on the host tissue following complete degradation. PMID:22922249

  11. Analysis the Clinical Curtive Effect of Thoracic Lumbar Spine Fractures of Posterior Pedicle Screw Fixation Combined Bone Graft Surgery%脊柱胸腰段骨折行后路椎弓根螺钉内固定联合植骨手术的临床疗效分析

    Institute of Scientific and Technical Information of China (English)

    慕志广

    2016-01-01

    Objective To evaluate the clinical curative effect for joint posterior pedicle screw internal fixation bone graft surgery in treatment of thoracic lumbar spine fractures.Methods Selected 72 cases of thoracic lumbar spine fracture patients in our hospital, which were randomly divided into two groups, each group had 36 cases, control group with posterior pedicle screw internal fixation treatment, the observation group patients give posterior pedicle screw internal fixation with bone graft surgery therapy.ResultsAfter surgery, VAS score, Cobb Angle observation group were better than the control group (P<0.05), two groups of data difference was statistically signiifcant (P<0.05).Conclusion Posterior pedicle screw internal fixation with bone graft surgery therapy thoracic lumbar spine fracture effect is remarkable was statistically significant (P<0.05). Conclusion Posterior pedicle screw internal fixation with bone graft surgery therapy thoracic lumbar spine fracture effect is remarkable.%目的:探讨后路椎弓根螺钉内固定联合植骨手术治疗脊柱胸腰段骨折的临床疗效。方法将我院收治的72例脊柱胸腰段骨折患者随机分为两组,各36例。对照组单用后路椎弓根螺钉内固定治疗,观察组给予后路椎弓根螺钉内固定联合植骨手术治疗。结果手术后,观察组VAS评分、Cobb角均优于对照组(P<0.05),差异有统计学意义(P<0.05)。结论后路椎弓根螺钉内固定联合植骨手术治疗脊柱胸腰段骨折效果显著。

  12. Surgical management of proximal splint bone fractures in the horse

    International Nuclear Information System (INIS)

    Fractures of Metacarpal and Metatarsal II and IV (the splint bones) were treated in 283 horses over an 11 year period. In 21 cases the proximal portion of the fractured bone was stabilized with metallic implants. One or more cortical bone screws were used in 11 horses, and bone plates were applied in 11 horses. One horse received both treatments. Complications of screw fixation included bone failure, implant failure, radiographic lucency around the screws, and proliferative new bone at the ostectomy site. Only two of the horses treated with screw fixation returned to their intended use. Complications of plate fixation included partial fixation failure (backing out of screws), wound drainage, and proliferative bony response around the plate. Six of the 11 horses treated by plate fixation returned to their intended use. The authors recommend consideration of plate fixation techniques for repair of fractures in the proximal third of the splint bone

  13. Implant materials for fracture fixation: a clinical perspective.

    Science.gov (United States)

    Disegi, J A; Wyss, H

    1989-01-01

    The optimum management of traumatic skeletal fractures may involve the installation of high quality surgical implants by a skilled orthopedic surgeon. Satisfactory clinical results are very dependent on the ability to maintain stable fracture fixation. Well designed contemporary implants rely on precise control of material composition and properties to achieve a well tolerated level of biological response. Metallic materials, such as 316L stainless steel, pure titanium, and titanium alloys, demonstrate an acceptable combination of strength, ductility, corrosion resistance, and biocompatibility. Polymers, composites, and biodegradable materials may offer selected opportunities for fracture fixation. An understanding of relevant clinical factors is essential to evaluate potential applications for advanced materials. PMID:2915951

  14. Guide to radiation fixatives

    International Nuclear Information System (INIS)

    This report identifies and then characterizes a variety of substances available in the market place for potential effectiveness as a fixative on radiologically contaminated surfaces. The substances include both generic chemicals and proprietary products. In selecting a fixative for a particular application, several attributes of the fixative may be relevant to the choice. These attributes include: toxicity, durability, and cleanliness and removability. In addition to the attributes of the fixative, one should also take into account certain characteristics of the site to be treated. These characteristics relate to climate, nature of the surface, use to which the treated surface will be put, subsequent cleanup operations, and type of neighboring surfaces. Finally, costs and potential environmental effects may influence the decision. A variety of fixatives are evaluated with respect to these various attributes and summarized in a reference table

  15. A new adhesive technique for internal fixation in midfacial surgery

    Directory of Open Access Journals (Sweden)

    Riediger Dieter

    2008-05-01

    Full Text Available Abstract Background The current surgical therapy of midfacial fractures involves internal fixation in which bone fragments are fixed in their anatomical positions with osteosynthesis plates and corresponding screws until bone healing is complete. This often causes new fractures to fragile bones while drilling pilot holes or trying to insert screws. The adhesive fixation of osteosynthesis plates using PMMA bone cement could offer a viable alternative for fixing the plates without screws. In order to achieve the adhesive bonding of bone cement to cortical bone in the viscerocranium, an amphiphilic bone bonding agent was created, analogous to the dentin bonding agents currently on the market. Methods The adhesive bonding strengths were measured using tension tests. For this, metal plates with 2.0 mm diameter screw holes were cemented with PMMA bone cement to cortical bovine bone samples from the femur diaphysis. The bone was conditioned with an amphiphilic bone bonding agent prior to cementing. The samples were stored for 1 to 42 days at 37 degrees C, either moist or completely submerged in an isotonic NaCl-solution, and then subjected to the tension tests. Results Without the bone bonding agent, the bonding strength was close to zero (0.2 MPa. Primary stability with bone bonding agent is considered to be at ca. 8 MPa. Moist storage over 42 days resulted in decreased adhesion forces of ca. 6 MPa. Wet storage resulted in relatively constant bonding strengths of ca. 8 MPa. Conclusion A new amphiphilic bone bonding agent was developed, which builds an optimizied interlayer between the hydrophilic bone surface and the hydrophobic PMMA bone cement and thus leads to adhesive bonding between them. Our in vitro investigations demonstrated the adhesive bonding of PMMA bone cement to cortical bone, which was also stable against hydrolysis. The newly developed adhesive fixing technique could be applied clinically when the fixation of osteosynthesis plates

  16. Comparison of Routine Fixation of Tissues with Rapid Tissue Fixation

    OpenAIRE

    Tripathi, Meenakshi; Bansal, Rani; Gupta, Mamta; Bharat, Vinay

    2013-01-01

    Introduction: Conventional formalin-fixed, paraffin-embedded tissue provides superior cellular morphology and long-term storage. Problems with formalin fixation comprise delay of fixation and variations in the duration of fixation. Microwave assisted tissue fixation removes the use of noxious and potentially toxic formalin that decreases the turnaround time and creates a personnel friendly workflow.

  17. Hexapod External Fixation of Tibia Fractures in Children.

    Science.gov (United States)

    Iobst, Christopher A

    2016-06-01

    Most tibia fractures in children can be treated nonoperatively. For fractures that do require surgery, however, the most common methods of management include plating or flexible nail insertion. Some fracture patterns, such as periphyseal fractures, fractures with bone and/or soft tissue loss, or fractures with delayed presentation, are not easily amenable to these techniques. Hexapod external fixators are especially helpful in these difficult cases. The purpose of this review is to discuss the principles of performing hexapod circular external fixation applied to pediatric tibia fractures. Some of the additional capabilities of the hexapod external fixator will also be highlighted. PMID:27078228

  18. GSS pedicle screw fixation combined with two-stage bone cement perfusion for thoracolumbar fractures%GSS椎弓根螺钉内固定并二期伤椎骨水泥灌注治疗胸腰椎骨折

    Institute of Scientific and Technical Information of China (English)

    宋洁富; 李利军; 常峰; 荆志振

    2012-01-01

    Objective To explore the efficacy and safety of surgical treatment of thoracolumbar fractures by GSS pedicle screw fixation combined with two-stage bone cement perfusion. Methods From March 2005 to October 2010, 31 patients with thoracolumbar bursting fractures were treated with posterior GSS pedicle screw fixation. The patients were reviewed by X-ray and CT scan 3-18 months postoperatively. Once "eggshell phenomenon" appeared, bone cement was used in the injured vertebral body before removing the fixators. Injured vertebral height and Cobb' s angle were measured preoperatively, postoperatively and at the final follow-up. Results No leakage of bone cement happened in all the patients. The internal fixators were removed 12-18 months postoperatively. Then the patients were followed up for 1-3 years. Fractured vertebral height and Cobb' s angle were significantly improved after surgery. Conclusion GSS combined with two-stage bone cement perfusion for thoracolumbar fractures can achieve a good therapeutic effect. It can be taken as an attempt at the treatment of thoracolumbar fractures.%目的 探讨GSS椎弓根螺钉内固定结合二期伤椎骨水泥灌注治疗胸腰椎骨折的有效性和安全性.方法 2005年3月~2010年10月共31例胸腰椎爆裂性骨折患者行后路GSS椎弓根螺钉内固定治疗,术后3~18个月根据X线及CT复查情况,出现"蛋壳现象"的患者在取出内固定前行伤椎骨水泥灌注,记录术前、术后及末次随访时的伤椎高度及X线片测量的Cobb角角度.结果 本组患者均未出现骨水泥渗漏,术后12~18个月取出内固定后再随访1~3年.术后伤椎椎体高度及Cobb角与术前相比有明显改善.结论 GSS椎弓根螺钉内固定结合二期伤椎骨水泥灌注治疗胸腰椎骨折可达到良好的治疗效果,可作为治疗胸腰椎骨折的新的尝试.

  19. Experimental study of bone morphogenetic proteins-2 slow release from an artificial trachea made of biodegradable materials: evaluation of stenting time.

    Science.gov (United States)

    Yamamoto, Yasumichi; Okamoto, Taku; Goto, Masashi; Yokomise, Hiroyasu; Yamamoto, Masaya; Tabata, Yasuhiko

    2003-01-01

    We manufactured an artificial trachea that slowly releases bone morphogenetic protein 2 (BMP-2) and used it to replace a section of the canine trachea. We made a three-layered prosthesis composed of an outer layer of gelatin sponge, a middle layer of collagen sponge, and an inner silicone tube. BMP-2 solution was soaked into the gelatin sponge layer. An approximately 3 cm length of the canine trachea was resected, and the artificial trachea was inserted into the resulting gap and anastomosed. The implanted portion was covered by periosteum. At 2, 4, and 8 weeks after surgery, the inner silicone tube was removed. Soon after removal of the silicone tube at 2 and 4 weeks, the dogs died of choking because of collapse of the trachea. One dog whose silicone tube was removed at 8 weeks was able to survive without choking. At 6 months after removal of the silicone tube, the bronchoscopic findings revealed that the gap in the trachea had been closed by regenerated tissue and covered by mucosa. We have demonstrated that our artificial trachea slowly releasing BMP-2 requires at least 8 weeks to achieve regeneration of solid tissue to support the tracheal gap. PMID:14524559

  20. Multiple Looping Technique for Tibial Fixation in Posterior Cruciate Ligament Reconstruction of the Knee

    OpenAIRE

    Noh, Jung Ho; Yoon, Kyoung Ho; Song, Sang Jun; Roh, Young Hak; Lee, Jae Woo

    2015-01-01

    The outcomes of posterior cruciate ligament reconstruction may be negatively affected by insufficient tibial tunnel fixation due to relatively lower bone density of the proximal tibia. We introduce a new technique of tibial fixation for posterior cruciate ligament reconstruction using free tendon Achilles allograft that is less affected by the bone density of the tibial metaphysis.

  1. Outcomes of Ilizarov ring fixation in recalcitrant infected tibial non-unions – a prospective study

    OpenAIRE

    Shah Harshad M; Manjunath KS; Ramesh Balasundaram; Madhusudhan Thayur R; Sundaresh Dabir C; Krishnappa N

    2008-01-01

    Abstract Background Infected non-union of long bones is a problem in the developing countries. Persistent infection, deformity, shortening, bone loss, joint stiffness and disability complicate the non-union. Secondary procedures are often required for correction of bone defects and deformity. Ilizarov method addresses all the above problems simultaneously and offers a panacea for infected non-unions. The stability of the fixation and provision for bone transport allows bridging of bone defect...

  2. 脊柱结核内植物置入后基于C-反应蛋白及红细胞沉降率多样性与植骨融合时间的相关分析%C-reactive protein and erythrocyte sedimentation rate associate with bone graft union in patients with spinal tuberculosis following internal fixation

    Institute of Scientific and Technical Information of China (English)

    蓝常贡; 唐毓金; 陆敏安; 韦玮; 谢克恭; 潘生才; 卢贤哲

    2012-01-01

    背景:脊柱结核行结核病灶清除、植骨、加或不加钢板内固定后患者C-反应蛋白及红细胞沉降率变化与植骨块骨性融合时间有一定的联系.目的:分析脊柱结核内置物置入后C-反应蛋白及红细胞沉降率动态多样性和植骨融合时间的相关性.方法:60例脊柱结核患者均行结核病灶清除、自体髂骨植骨、加或不加钢板内固定治疗,其中内固定38例,无内固定22例.根据术后C-反应蛋白水平及红细胞沉降率分别分为轻度升高、中度升高、高度升高组和极度升高组.分析术后C-反应蛋白、红细胞沉降率和植骨块骨性融合时间差异性和相关性.结果与结论:①C-反应蛋白:轻度升高18例,中度升高21例,高度升高13例,极度升高8例.4组骨性愈合时间差异有非常显著性意义(P=0.003).Spearman相关分析显示相关系数为r=0.420,P=0.001,说明术后C-反应蛋白水平多样性与骨性融合时间长短呈正相关.②红细胞沉降率:轻度升高16例,中度升高20例,高度升高13例,极度升高11例.4组骨性愈合时间差异有非常显著性意义(P=0.003).Spearman相关分析显示相关系数为r=0.414,P=0.001,说明术后红细胞沉降率多样性与骨性融合时间长短呈正相关.③内固定组植骨融合时间快于无内固定组,说明即时坚强内固定有利于促进骨性愈合.%BACKGROUND: Tuberculosis clearance, bone graft, internal fixation with or without plate for patients with spinal tuberculosis always lead to C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) changes, which are associated with bone graft union time to certain degree.OBJECTIVE: To analyze the correlation between CRP, ESR and bone graft union time in patients with spinal tuberculosis.METHODS: A total of 60 patients with spinal tuberculosis underwent tuberculose focus clearance, autologous iliac bone grafting, and internal fixation without or with plate, including 38 undergoing fixation

  3. Bone cement-augmented pedicle screw fixation for lumbar spondylolisthesis combined with osteoporosis:1-year follow-up%骨水泥强化椎弓根螺钉置入固定骨质疏松性腰椎滑脱:1年随访

    Institute of Scientific and Technical Information of China (English)

    丁权; 陈勇

    2015-01-01

    BACKGROUND:For patients with lumbar spondylolisthesis combined with osteoporosis, appropriate fixation system for effective reset and good fixation stability is currently a hot issue of clinical concern. Pedicle screw screw-rod system after bone cement perfusion can achieve the effective fixation between pedicle screw system and the vertebral bone. OBJECTIVE:To observe the therapeutic effect of bone cement-augmented pedicle screw on patients with lumbar spondylolisthesis combined with osteoporosis. METHODS:17 cases of lumbar spondylolisthesis combined with osteoporosis were identified by bone density test. They received the posterior open reduction and internal fixation, and implanted with 68 bone cement-augmented pedicle screws. Their repair effects were observed by short-term fol ow-up. Patients were evaluated using low back pain Visual Analog Scale and lower limb Oswestry Disability Index before treatment, 1 week, 3 months and 1 year after treatment. Vertebral height, intervertebral height, screw loosening and bone cement leakage were observed using imaging. RESULTS AND CONCLUSION:Compared with pre-treatment, low back pain Visual Analog Scale score and lower limb Oswestry Disability Index were significantly improved at 1 week, 3 months and 1 year after treatment (P0.05), which indicated that clinical repair effect could be effectively maintained. At 3 months of fol ow-up, one screw loosening occurred in two patients. During fixation, mild bone cement leakage appeared in seven vertebral bodies with screw fixation, no symptoms or subsequent complications were observed. There were no significant differences in vertebral height and intervertebral height before and after treatment and during fol ow-up (P>0.05). These results suggest that bone cement-augmented pedicle screw for patients with lumbar spondylolisthesis combined with osteoporosis can effectively reset vertebral slippage, effectively provide good anti-pul-out force for a long term, and the effect was

  4. Biodegradability of Plastics

    Directory of Open Access Journals (Sweden)

    Yutaka Tokiwa

    2009-08-01

    Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  5. Desenvolvimento e desempenho de um fixador flexível na consolidação de fraturas diafisárias transversais provocadas iatrogênicamente na tíbia de carneiros Development and performance of a flexible fixator on bone healing of transverse diaphyseal fracture caused iatrogenically in the sheep tibiae

    Directory of Open Access Journals (Sweden)

    Giuliano Barbieri

    2011-06-01

    Full Text Available Foi realizado um estudo experimental sobre o desenvolvimento e desempenho de um fixador externo flexível no processo de consolidação de tíbias de carneiros submetidas à osteotomia transversa mediodiafisária. Foram empregados no estudo 20 carneiros da raça Santa Inês, com massa corporal média de 37kg, divididos em diferentes grupos conforme o período de observação pós-operatória, de 30, 45, 60 e 90 dias. Ao final, os animais sofreram a eutanásia e as tíbias foram removidas para estudo de volumetria transversal do calo ósseo por tomografia computadorizada e ensaio mecânico destrutivo. Os resultados mostraram que ocorreu a formação de calo ósseo volumoso, caracterizando assim a ocorrência de deslocamento de carga axial para o foco da osteotomia, promovida pelo fixador externo utilizado. No ensaio mecânico, observou-se que as comparações entre os grupos respectivos intactos e operados foram significantemente diferentes (PAn experimental study was carried out to verify the development and performance of a flexible external fixator on the bone healing process of the tibia of sheep submitted to a transverse diaphyseal osteotomy. It was used twenty Santa Inês sheep with average weigh of 37kg divided in groups, according to the period of postoperative observation of 30, 45, 60 and 90 days. At the end, the animals were sacrificed and the tibiae were removed for study of transverse callus volumetric by computed tomography and destructive mechanical testing. The results had shown that the formation of voluminous callus occurred, thus characterizing the occurrence of displacement of axial load to the focus of the osteotomy, promoted by the used external fixator used. The mechanical testing showed that the comparisons between the respective intact and operated groups were significantly different (P<0.05 except for the group with 90 days, which demonstrated equivalent stiffness when compared to normal bone. In none of the animals

  6. Immediate ipsilateral fibular transfer in a large tibial defect using a ring fixator : A case report

    OpenAIRE

    Kim, H S; Jahng, J. S.; Han, D. Y.; Park, H. W.; Chun, C. H.

    1998-01-01

    Massive segmental bony defects in open tibial fractures are generally treated with conventional bone grafting, a free vascularised fibular graft or the ring fixator technique. A vascularised fibular graft may be superior to a conventional bone graft, but it is technically difficult and occasionally impossible. In such circumstances, fibular transfer in conjunction with a ring fixator is an alternative method. This procedure can be accomplished by transferring the osteotomised part of the fibu...

  7. 空心拉力螺钉加镍钛聚髌器置入内固定重建骨折髌骨的生物力学条件%Biomechanical requirement for the reconstruction of patellar fracture treated with cancellous bone screw and nickel-titanium-patellar concentrator internal fixation

    Institute of Scientific and Technical Information of China (English)

    高振巢; 刘德昌; 蔡国平

    2013-01-01

    BACKGROUND: There are various internal fixation methods for the clinical treatment of patel ar fractures, but each method has advantages and disadvantages, respectively. The selection of proper internal fixation method wil directly affect the healing time and recovery of knee joint function. OBJECTIVE: To investigate the biomechanical reconstruction effect on patel ar fracture treated with cancel ous bone screw and nickel-titanium-patel ar concentrator internal fixation. METHODS: A retrospective analysis was performed on 27 cases of acute patel ar fracture patients from January 2011 to January 2012 in the Department of Orthopedics, Jinshan Hospital, Fudan University, including 13 cases of transverse fracture, 11 cases of comminuted fracture and three cases of upper or lower pole fracture. Al the 27 patients received cancel ous bone screw and nickel-titanium-patel ar concentrator internal fixation without plaster external fixation, and then the quadriceps active contraction training was performed from the 2nd day after internal fixation, and bed knee flexion and extension exercises were performed at 1 week after internal fixation. The knee joint function was evaluated with Böstman score system. RESULTS AND CONCLUSION: Al the 27 patients were fol owed-up for 4-14 months. Incisions obtained stage Ⅰ healing, and there was no fracture fixation or shedding, wound infection, skin necrosis or other complications. The average healing time was 8.5 weeks without delayed healing. According to clinical grading scale of Böstman score system, the mean score was 27.9, included 27 cases of excel ent (81%), four cases of good (15%), one case of poor (4%), and the excel ent and good rate was 96%. The results suggest that cancel ous bone screw combined with nickel-titanium-patel ar concentrator internal fixation can maintain the advantages of traditional internal fixation method, and can avoid the disadvantages of the traditional internal fixation method.%  背景:目前

  8. Fixação de fraturas ilíacas em cães com parafusos, fios de aço e cimento ósseo de polimetilmetacrilato Canine iliac fracture fixation with screws, orthopedic wire and polymethylmethacrylate bone cement

    Directory of Open Access Journals (Sweden)

    Claudio Roehsig

    2008-09-01

    Full Text Available O presente trabalho teve como objetivo verificar a recuperação da locomoção e o tempo para cicatrização óssea de fraturas ilíacas fixadas com parafusos, fios de aço e cimento ósseo de polimetilmetacrilato. Dezesseis cães de ambos os sexos, com peso de 1,8 a 16kg e idade entre sete meses e 11 anos, foram submetidos à osteossíntese da fratura de ílio, provocadas por acidente automobilístico. Em dois animais, realizou-se osteossíntese bilateral, totalizando 18 ossos ilíacos operados. A abordagem ao ílio foi lateral e quando necessária estendida caudalmente através da osteotomia do trocanter maior. As fraturas foram reduzidas e, em cada segmento ósseo, foram implantados dois a três parafusos e banda de tensão com fio de aço entre os parafusos adjacentes à linha de fratura. Sobre esses implantes aplicou-se cimento ósseo misturado com cefazolina sódica e após o endurecimento prosseguiu-se com a síntese dos tecidos moles com suturas rotineiramente utilizadas na clinica cirúrgica. No período pós-operatório, foram realizadas avaliações até 90 dias após a osteossíntese e observou-se locomoção apropriada em 15 animais. Avaliações radiográficas demonstraram sinais de completa consolidação óssea entre 60 e 90 dias. Falha da estabilização ocorreu em dois casos, obrigando a reintervenção cirúrgica em um deles. A partir dos resultados obtidos, é possível concluir que, em cães com até 16kg de peso, a fixação de fraturas ilíacas utilizando parafusos cimentados com PMMA constitui uma eficiente técnica, que proporciona adequada estabilidade, precoce recuperação funcional e cicatrização óssea.The present study aimed to verify the time for locomotion recovery and bone healing in canine iliac fractures fixated with screws, orthopedic wires and methylmetacrylate bone cement. Sixteen dogs from both genders accidentally hit by a car and showing iliac fractures were included. Dogs aged from 7 months to 11

  9. Clinical application of augmented pedicle screw fixation with bone cement in lumber spondylolisthesis accompanied with osteoporosis%骨水泥强化椎弓根螺钉在腰椎滑脱伴骨质疏松椎体中的临床应用

    Institute of Scientific and Technical Information of China (English)

    李鹏; 毛克亚; 王岩; 肖嵩华; 张永刚; 张西峰; 张雪松; 程自申; 毛克政

    2011-01-01

    目的 探讨骨水泥强化椎弓根螺钉在腰椎滑脱伴骨质疏松患者的手术方法和疗效.方法 2008年7月至2010年11月年期间收治腰椎滑脱伴骨质疏松患者12例,平均68岁.骨质疏松按Jikei分级Ⅱ级4例,Ⅲ级8例.所有患者行经椎弓根螺钉内固定,术中采用骨水泥强化提高螺钉稳定性,植入椎弓根螺钉共26枚,观察椎弓根螺钉术中及术后的稳定性.结果 患者未发生手术并发症,腰腿痛症状改善明显,术后VAS评分较术前比较改善明显.12例患者均获得随访,随访时间8-16个月,平均14个月.12例均获得骨性融合,X线片显示内固定无松动、断裂或脱落,螺钉周围未见透亮线出现.结论 经椎弓根骨水泥强化椎弓根螺钉,固化椎体的同时增加了椎弓根螺钉界面把持力,能够满足腰椎滑脱伴骨质疏松患者脊椎后路固定手术对力学稳定的要求.%Objective To explore the surgical method and efficacy of augmented pedicle screw fixation with bone cement for the treatment of lumber spondyiolisthesis accompanied with osteoporosis. Methods Twelve lumber spondyiolisthesis patients accompanied with osteoporosis were collected and treated from July 2008 to November 2010, with an average age of 68 years old. According to Jikei scale for osteoporosis, 4 patients were in stage II and 8 patients were in stage III. All patients were treated with internal fixations of pedicle screws and the stabilities of screws were augmented by bone cement augment during operations. Twenty-six pedicle screws were instrumented in this study. The stabilities of pedicle screws during and after the operation were observed. Results There were no operative complications. The symptoms of waist and leg pain were clearly alleviated. The VAS scores after operations were clearly ameliorated compared to those before the operation. All 12 patients were followed up for 8-16 months, with a mean of 14 months. All 12 patients achieved bone unions. The X

  10. PERCUTANEOUS BIPLANAR EXTERNAL FIXATOR METHOD FOR TREATMENT OF CALCONEAL FRACTURES

    OpenAIRE

    Jagadeesh Kumar; Parthasaradhy M.; Subramanian,; Thiyageswaran; Abinandharajha; Adhiyamaan; Shivakumar

    2015-01-01

    Calcaneal fracture, the most common tarsal bone fracture, occurs predominantly in manual labors and subsequently has got considerable socioeconomic implications. Treatment modality which can offer early weight bearing and early return to work is therefore needed for those patient s. We have used a biplanar percutaneous external fixator for treating calcaneal fractures per operative visualization of the fractures. We have treated 20 ca...

  11. Rigid internal fixation of zygoma fractures: A comparison of two-point and three-point fixation

    Directory of Open Access Journals (Sweden)

    Parashar Atul

    2007-01-01

    Full Text Available Background: Displaced fractures of the zygomatic bone can result in significant functional and aesthetic sequelae. Therefore the treatment must achieve adequate and stable reduction at fracture sites so as to restore the complex multidimensional relationship of the zygoma to the surrounding craniofacial skeleton. Many experimental biophysical studies have compared stability of zygoma after one, two and three-point fixation with mini plates. We conducted a prospective clinical study comparing functional and aesthetic results of two-point and three-point fixation with mini plates in patients with fractures of zygoma. Materials and Methods: Twenty-two patients with isolated zygomatic fractures over a period of one year were randomly assigned into two-point and three-point fixation groups. Results of fixation were analyzed after completion of three months. This included clinical, radiological and photographic evaluation. Results: The three-point fixation group maintained better stability at fracture sites resulting in decreased incidence of dystopia and enophthalmos. This group also had better malar projection and malar height as measured radiologically, when compared with the two-point fixation group. Conclusion: We recommend three-point rigid fixation of fractured zygoma after accurate reduction so as to maintain adequate stabilization against masticatory forces during fracture healing phase.

  12. Radionuclides fixation by hydroxyapatite

    International Nuclear Information System (INIS)

    Some characteristic results on strontium fixation by coprecipitation and sorption with hydroxyapatite are presented. Coprecipitation experiments performed at wide range of experimental conditions have confirmed that strontium incorporated into hydroxyapatite by isomorphous substitution of calcium. Adsorption on the surface of well crystallized hydroxyapatite follows Langmuir's adsorption isotherm with monolayer capacity of 1.5 10-4 mol/g. (author)

  13. Grey water biodegradability.

    Science.gov (United States)

    Ghunmi, Lina Abu; Zeeman, Grietje; Fayyad, Manar; van Lier, Jules B

    2011-02-01

    Knowing the biodegradability characteristics of grey water constituents is imperative for a proper design and operation of a biological treatment system of grey water. This study characterizes the different COD fractions of dormitory grey water and investigates the effect of applying different conditions in the biodegradation test. The maximum aerobic and anaerobic biodegradability and conversion rate for the different COD fractions is determined. The results show that, on average, dormitory grey water COD fractions are 28% suspended, 32% colloidal and 40% dissolved. The studied factors incubation time, inoculum addition and temperature are influencing the determined biodegradability. The maximum biodegradability and biodegradation rate differ between different COD fractions, viz. COD(ss), COD(col) and COD(diss). The dissolved COD fraction is characterised by the lowest degradation rate, both for anaerobic and aerobic conditions. The maximum biodegradability for aerobic and anaerobic conditions is 86 and 70% respectively, whereas the first order conversion rate constant, k₂₀, is 0.119 and 0.005 day⁻¹, respectively. The anaerobic and aerobic conversion rates in relation to temperature can be described by the Arrhenius relation, with temperature coefficients of 1.069 and 1.099, respectively. PMID:20658309

  14. A cell shrinkage artefact in growth plate chondrocytes with common fixative solutions: importance of fixative osmolarity for maintaining morphology

    Directory of Open Access Journals (Sweden)

    MY Loqman

    2010-05-01

    Full Text Available The remarkable increase in chondrocyte volume is a major determinant in the longitudinal growth of mammalian bones. To permit a detailed morphological study of hypertrophic chondrocytes using standard histological techniques, the preservation of normal chondrocyte morphology is essential. We noticed that during fixation of growth plates with conventional fixative solutions, there was a marked morphological (shrinkage artifact, and we postulated that this arose from the hyper-osmotic nature of these solutions. To test this, we fixed proximal tibia growth plates of 7-day-old rat bones in either (a paraformaldehyde (PFA; 4%, (b glutaraldehyde (GA; 2% with PFA (2% with ruthenium hexamine trichloride (RHT; 0.7%, (c GA (2% with RHT (0.7%, or (d GA (1.3% with RHT (0.5% and osmolarity adjusted to a ‘physiological’ level of ~280mOsm. Using conventional histological methods, confocal microscopy, and image analysis on fluorescently-labelled fixed and living chondrocytes, we then quantified the extent of cell shrinkage and volume change. Our data showed that the high osmolarity of conventional fixatives caused a shrinkage artefact to chondrocytes. This was particularly evident when whole bones were fixed, but could be markedly reduced if bones were sagittally bisected prior to fixation. The shrinkage artefact could be avoided by adjusting the osmolarity of the fixatives to the osmotic pressure of normal extracellular fluids (~280mOsm. These results emphasize the importance of fixative osmolarity, in order to accurately preserve the normal volume/morphology of cells within tissues.

  15. Fracture fixation with two locking screws versus three non-locking screws

    OpenAIRE

    Grawe, B.; Le Van, T.; Williamson, S.; Archdeacon, A.; Zardiackas, L

    2012-01-01

    Objectives We aimed to further evaluate the biomechanical characteristics of two locking screws versus three standard bicortical screws in synthetic models of normal and osteoporotic bone. Methods Synthetic tubular bone models representing normal bone density and osteoporotic bone density were used. Artificial fracture gaps of 1 cm were created in each specimen before fixation with one of two constructs: 1) two locking screws using a five-hole locking compression plate (LCP) plate; or 2) thre...

  16. Hollow-Bone-Graft Dynamic Hip Screw Can Fix and Promote Bone Union after Femoral Neck Fracture: an Experimental Research

    OpenAIRE

    SHEN, Jia-zuo; YAO, Jian-fei; LIN, Da-sheng; Lian, Ke-jian; Ding, Zhen-qi; Lin, Bin; GUO, Zhi-min; Zhang, Ming-Hua; Li, Qiang; LI, Lin; Qi, Peng

    2012-01-01

    Background: Delayed bone union, nonunion or osteonecrosis often occur after femoral neck fractures in young adults. Secondary bone healing requires strong internal fixation, intramedullary pressure reduction and early functional exercise. Objective: To compare bone healing of femoral neck fractures treated with hollow-bone-graft dynamic hip screws (Hb-DHS) and standard dynamic hip screws (DHS) in an animal model. Design: Testing of specifically designed fixation devices in a pig animal model....

  17. Hollow-Bone-Graft Dynamic Hip Screw Can Fix and Promote Bone Union after Femoral Neck Fracture: an Experimental Research

    OpenAIRE

    Jia-zuo SHEN, Jian-fei YAO, Da-sheng LIN, Ke-jian LIAN, Zhen-qi DING, Bin LIN, Zhi-min GUO, Ming-hua ZHANG, Qiang LI, Lin LI, Peng QI

    2012-01-01

    Background: Delayed bone union, nonunion or osteonecrosis often occur after femoral neck fractures in young adults. Secondary bone healing requires strong internal fixation, intramedullary pressure reduction and early functional exercise.Objective: To compare bone healing of femoral neck fractures treated with hollow-bone-graft dynamic hip screws (Hb-DHS) and standard dynamic hip screws (DHS) in an animal model.Design: Testing of specifically designed fixation devices in a pig animal model.In...

  18. Comparative study on the biodegradation and biocompatibility of silicate bioceramic coatings on biodegradable magnesium alloy as biodegradable biomaterial

    Science.gov (United States)

    Razavi, M.; Fathi, M. H.; Savabi, O.; Razavi, S. M.; Hashemibeni, B.; Yazdimamaghani, M.; Vashaee, D.; Tayebi, L.

    2014-03-01

    Many clinical cases as well as in vivo and in vitro assessments have demonstrated that magnesium alloys possess good biocompatibility. Unfortunately, magnesium and its alloys degrade too quickly in physiological media. In order to improve the biodegradation resistance and biocompatibility of a biodegradable magnesium alloy, we have prepared three types of coating include diopside (CaMgSi2O6), akermanite (Ca2MgSi2O6) and bredigite (Ca7MgSi4O16) coating on AZ91 magnesium alloy through a micro-arc oxidation (MAO) and electrophoretic deposition (EPD) method. In this research, the biodegradation and biocompatibility behavior of samples were evaluated in vitro and in vivo. The in vitro analysis was performed by cytocompatibility and MTT-assay and the in vivo test was conducted on the implantation of samples in the greater trochanter of adult rabbits. The results showed that diopside coating has the best bone regeneration and bredigite has the best biodegradation resistance compared to others.

  19. Primary stability of inferior tilt fixation of the glenoid component in reverse total shoulder arthroplasty: A finite element study.

    Science.gov (United States)

    Chae, Soo-Won; Lee, Haea; Kim, Soo Min; Lee, Juneyoung; Han, Seung-Ho; Kim, Soung-Yon

    2016-06-01

    Glenoid component fixation with inferior tilt has been suggested as one of the surgical methods to decrease scapular notching and improve stability, but its clinically beneficial effect remains a concern. We evaluated the influence of inferior tilt fixation of the glenoid component on primary stability in reverse total shoulder arthroplasty by finite element analysis. Finite element models were constructed from cadaveric scapulae of females over the age of 60 years and glenoid components from reverse total shoulder arthroplasty. The relative micromotion at the bone-glenoid component interface, distribution of bone stress under the glenoid component and around the screws, contact area between the bone and screws, and cut surface area of the cancellous bone exposed after glenoid reaming were analyzed and compared between a neutral and 10° inferior tilt fixation of the glenoid component. The 10° inferior tilt fixation demonstrated greater relative micromotion and higher bone stress than the neutral tilt fixation. Eccentric reaming, which is done to produce the inferior tilt fixation of the glenoid component, increased glenoid cancellous bone exposure and decreased bone-screws contact area. Inferior tilt fixation of the glenoid component may adversely affect primary stability and longevity after reverse total shoulder arthroplasty. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1061-1068, 2016. PMID:26621211

  20. 植骨及内固定治疗半椎体和重度先天性脊柱侧后凸畸形:三维矫形的有效及安全性%Bone graft and internal fixation for the treatment of hemivertebrae and severe congenital kyphoscoliosis:Effectiveness and safety of three-dimensional correction

    Institute of Scientific and Technical Information of China (English)

    王晓平; 秦柳花; 郑蕊; 张敬; 陆明; 马华松; 周建伟; 袁伟; 牛晶; 崔凯; 陈阳; 黄子瑞

    2013-01-01

    BACKGROUND:Clinical treatment of hemivertebrae-induced congenital scoliosis is a complex medical problem. OBJECTIVE:To find the optimal treatment for hemivertebrae accompanied by congenital scoliosis. METHODS:Total y 142 hemivertebrae patients who had received surgical treatment in the Department of Orthopedics, the 306 Hospital of Chinese PLA, China from 2010 to 2012 were enrol ed. The main surgical treatment was hemivertebrae resection and bone fusion with internal fixation, apical osteotomy for severe scoliosis and spinal shortening with internal fixation, one-stage posterior thoracolumbar osteotomy with internal fixation, spinal decompression with internal fixation. RESULTS AND CONCLUSION:After treatment, the average correction rate was 70.9%for scoliosis and 71.7%for kyphosis. The fol ow-up period was 14-35 months, with an average of 23.4 months. By the end of the final fol ow-up, the loss rate for Cobb’s angle was 7.3%for scoliosis and 7.7%for kyphosis. Fol ow-up X-ray films showed bone fusion and internal fixation without loosening, fracture, and decompensation. Implementation of one-stage posterior thoracolumbar osteotomy with internal fixation can effectively correct hemivertebrae-induced kyphoscoliosis to obtain a satisfactory spinal sagittal and coronal balance.%背景:由半椎体形成的先天性脊柱侧弯在临床治疗上一直较为复杂。  目的:寻找治疗半椎体以及半椎体合并极重度先天性脊柱侧弯的最佳方法。  方法:选择2010至2012年间在解放军306医院骨科进行手术治疗的半椎体畸形患者共142例,手术治疗的方法主要为单纯半椎体切除植骨融合内固定,重度脊柱侧弯顶椎截骨脊柱短缩矫形内固定,一期后路胸腰椎截骨矫形,椎管减压矫形内固定手术。  结果与结论:治疗后侧凸平均矫正率为70.9%,后凸平均矫正率为71.7%,随访14-35个月,平均23.4个月。末次随访时侧凸Cobb角丢失率为7.3%

  1. Biodegradable modified Phba systems

    International Nuclear Information System (INIS)

    Compositions as well as production technology of ecologically sound biodegradable multicomponent polymer systems were developed. Our objective was to design some bio plastic based composites with required mechanical properties and biodegradability intended for use as biodegradable packaging. Significant characteristics required for food packaging such as barrier properties (water and oxygen permeability) and influence of γ-radiation on the structure and changes of main characteristics of some modified PHB matrices was evaluated. It was found that barrier properties were plasticizers chemical nature and sterilization with γ-radiation dependent and were comparable with corresponding values of typical polymeric packaging films. Low γ-radiation levels (25 kGy) can be recommended as an effective sterilization method of PHB based packaging materials. Purposely designed bio plastic packaging may provide an alternative to traditional synthetic packaging materials without reducing the comfort of the end-user due to specific qualities of PHB - biodegradability, Biocompatibility and hydrophobic nature

  2. Solid freeform fabrication of bone tissue engineering scaffolds

    Institute of Scientific and Technical Information of China (English)

    XIONG Zhuo; YAN Yongnian; ZHANG Renji; CHEN Lifeng; WANG Li

    2001-01-01

    @@ INTRODUCTIONTissue engineering is a promising approach to large segmental bone repair fortrauma, replacement surgery, skeletal deficiency or abnormal development. Thefabrication of bone regeneration scaffolds with appropriate bone conductive property,bone inductive property, biodegradation property and mechanical properties is thecrux of this approach.

  3. Green and biodegradable electronics

    OpenAIRE

    Mihai Irimia-Vladu; Eric. D. Głowacki; Gundula Voss; Siegfried Bauer; Niyazi Serdar Sariciftci

    2012-01-01

    We live in a world where the lifetime of electronics is becoming shorter, now approaching an average of several months. This poses a growing ecological problem. This brief review will present some of the initial steps taken to address the issue of electronic waste with biodegradable organic electronic materials. Many organic materials have been shown to be biodegradable, safe, and nontoxic, including compounds of natural origin. Additionally, the unique features of such organic materials sugg...

  4. Polymer-Ceramic Spiral Structured Scaffolds for Bone Tissue Engineering: Effect of Hydroxyapatite Composition on Human Fetal Osteoblasts

    OpenAIRE

    Zhang, Xiaojun; Chang, Wei; Lee, Paul; Wang, Yuhao; Yang, Min; Li, Jun; Kumbar, Sangamesh G.; Yu, Xiaojun

    2014-01-01

    For successful bone tissue engineering, a scaffold needs to be osteoconductive, porous, and biodegradable, thus able to support attachment and proliferation of bone cells and guide bone formation. Recently, hydroxyapatites (HA), a major inorganic component of natural bone, and biodegrade polymers have drawn much attention as bone scaffolds. The present study was designed to investigate whether the bone regenerative properties of nano-HA/polycaprolactone (PCL) spiral scaffolds are augmented in...

  5. CARBON DIOXIDE FIXATION.

    Energy Technology Data Exchange (ETDEWEB)

    FUJITA,E.

    2000-01-12

    Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

  6. Improving Carbon Fixation Pathways

    OpenAIRE

    Ducat, Daniel C.; Silver, Pamela A.

    2012-01-01

    A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will necessitate improvements in crop carbon-fixation efficiencies. Photosynthesis in traditional terrestrial crops is being reexamined in light of molecular strategies employed by photosynthetic microbes to enhance the activity of the Calvin cycle. Synthetic biology is well-situated to provide original approaches for compartmentalizing...

  7. Significantly lower femoral neck growth in screw fixation of the asymptomatic contralateral hip in unilateral slipped capital femoral epiphysis.

    Science.gov (United States)

    Wölfle-Roos, Julia V; Urlaub, Stefanie; Reichel, Heiko; Taurman, Rita

    2016-05-01

    There is an ongoing debate on which fixation technique should be preferred for the prophylactic fixation of the asymptomatic contralateral hip in slipped capital femoral epiphysis (SCFE). In the case of Kirschner-wire (K-wire) fixation, there is a possibility of secondary loss of fixation because of longitudinal growth of the physis, whereas in screw fixation, physeal growth of the femoral neck might be impaired. The aim of this matched-pair study was to compare the longitudinal growth of the femoral neck in screw fixation versus K-wire fixation of the asymptomatic contralateral hip in SCFE. All 18 patients (female : male=3 : 15), who had undergone screw fixation of the asymptomatic contralateral hip between 9/2001 and 9/2011, were matched according to age, bone age, sex, and time to follow-up to another 18 patients with K-wire fixation. The length of the femoral neck of the contralateral hip was measured in parallel to either screw or K-wire from the apex of the femoral head to the opposite cortical bone. The ratio of the femoral neck length measured directly after surgery and on follow-up was defined as femoral neck growth. There was no significant difference between groups with respect to age, modified Oxford Bone age score, and time to follow-up. We found a significant difference in femoral neck growth between patients with screw fixation (5.5±4.3%) compared with K-wire fixation (8.9±5.7%, P=0.048 matched Wilcoxon test). The difference in femoral neck growth of patients with K-wire or screw fixation of the contralateral asymptomatic hip in SCFE was small, but statistically significant. Thus, despite high rates of secondary loss of fixation, K-wire fixation should still be considered, especially in very young patients. PMID:26919622

  8. DEXA as a Predictor of Fixator Removal in Distraction Osteogenesis

    OpenAIRE

    Saran, Neil; Hamdy, Reggie C.

    2008-01-01

    Premature removal of the fixator after a lengthening procedure can result in gradual bending or acute fracture of the regenerate. We reviewed the records of 26 patients who underwent 28 limb lengthenings between 1997 and 2005 to assess the post lengthening regenerate fracture rate and bone healing index when using dual energy xray absorptiometry (DEXA) to aid in deciding on when to remove the fixator. Sixteen male and 10 female patients with an average age at lengthening of 12.3 years underwe...

  9. Augmentation of Pedicle Screw Fixation with Calcium Phosphate Cement

    Institute of Scientific and Technical Information of China (English)

    YANG Shu-hua; FU De-hao; LI Jin; XU Wei-hua; YANG Cao; YE Zhe-wei; ZUO Xiao-yan

    2004-01-01

    To determine whether a biodegradable calcium phosphate cement(CPC) provides significant augmentation of pedicle screw fixation or not,an in vitro biomechanical study was carried out to evaluate the biomechanical effect of CPC in the restoration and augmentation of pedicle screw fixation.Axial pullout test and cyclic bending resistance test were employed in the experiment,and polymethylmethacrylate (PMMA) was chosen as control.The results demonstrate that the pullout strengths following CPC restoration and augmentation are 74% greater on an average than those of the control group,but less than those of PMMA restoration group and augmentation group respectively (increased by 126% versus control).In cyclic bending resistance test,the CPC augmented screws are found to withstand a greater number of cycles or greater loading with less displacement before loosening,but the augmentation effect of PMMA is greater than that of CPC.

  10. The stiffness characteristics of hybrid Ilizarov fixators.

    Science.gov (United States)

    Baran, Onder; Havitcioglu, Hasan; Tatari, Hasan; Cecen, Berivan

    2008-10-20

    The use of hybrid Ilizarov models around femoral area is gaining clinical popularity lately. Hybrid systems show different mechanical properties. The purpose of this report is to examine the stiffness characteristics of the C-arch and half-pins on the hybrid Ilizarov fixators. Eight models that included standard Ilizarov and hybrid models were applied to six femoral sawbones. The distal part of fixation was composed of a two-ring frame applied identically to all bones. The difference of the configuration was at the proximal part, where half-pins with or without C-arches were either added to the proximal two-ring frame or replaced the proximal one- or two-ring frame. Osteotomy was performed in the femoral diaphysis and the bone was distracted 2cm. The stability of the system was tested with the axial compression testing machine. Displacements between the adjacent fracture sides were measured with the video extensometer in three dimensions. We found that proximal half-pin applications alone had less stiffness, but half-pins with C-arch had more stiffness than the model including only half-pins. Additional half-pins onto one- or two-ring frames had more longitudinal stiffness, but this system showed weak resistance against transverse displacement. PMID:18789446

  11. Fixation of osteochondral fragments in the human knee using Meniscus Arrows (R)

    NARCIS (Netherlands)

    Wouters, Diederick B.; Burgerhof, Johannes G. M.; de Hosson, Jeff. T. M.; Bos, Rudolf R. M.

    2011-01-01

    The aim of this study is to compare the hold in bone of Meniscus Arrows(A (R)) and Smart Nails(A (R)), followed by the report of the results of the clinical application of Meniscus Arrows(A (R)) as fixation devices. First, pull-out tests were performed to analyse the holdfast of both nails in bone.

  12. Fixation of osteochondral fragments in the human knee using Meniscus Arrows

    NARCIS (Netherlands)

    Wouters, D.B.; Burgerhof, J.G.; de Hosson, J.T.; Bos, R.R.

    2011-01-01

    The aim of this study is to compare the hold in bone of Meniscus Arrows and Smart Nails, followed by the report of the results of the clinical application of Meniscus Arrows as fixation devices. First, pull-out tests were performed to analyse the holdfast of both nails in bone. Statistical analysis

  13. Initial stability of cementless acetabular cups: press-fit and screw fixation interaction—an in vitro biomechanical study

    OpenAIRE

    Tabata, Tomonori; Kaku, Nobuhiro; Hara, Katsutoshi; Tsumura, Hiroshi

    2014-01-01

    Background Press-fit and screw fixation are important technical factors to achieve initial stability of a cementless acetabular cup for good clinical results of total hip arthroplasty. However, how these factors affect one another in initial cup fixation remains unclear. Therefore, this study aimed to evaluate the mutual influence between press-fit and screw fixation on initial cup stability. Methods Foam bone was subjected to exact hemispherical-shape machining to diameters of 48, 48.5 and 4...

  14. Estudo experimental da influência da altura do enxerto ósseo intersomático na estabilidade da fixação monossegmentar anterior da coluna cervical Experimental study of the impact of intersomatic bone graft height on the stability of anterior monosegmental fixation of the cervical spine

    Directory of Open Access Journals (Sweden)

    Jorge Alfredo Léo

    2008-06-01

    Full Text Available OBJETIVO: Estudar experimentalmente a influência da altura do enxerto ósseo intersomático da coluna cervical na estabilidade mecânica da fixação cervical anterior. MÉTODOS: Foram realizados ensaios mecânicos utilizando a coluna cervical de suínos (C3-C4. Foram formados três grupos experimentais compostos por 20 segmentos da coluna cervical (C3-C4, de acordo com o grau de instabilidade produzido e a fixação do segmento vertebral. Grupo I: retirada do disco intervertebral e colocação de enxerto intersomático. Grupo II: retirada do disco intervertebral, colocação de enxerto intersomático e fixação anterior com placa. Grupo III: retirada do disco intervertebral, secção dos ligamentos posteriores e cápsulas articulares bilateralmente, colocação do enxerto intersomático e fixação anterior com placa. Cada grupo experimental foi dividido em dois subgrupos, de acordo com a altura do enxerto ósseo utilizado (3,0mm ou 6,0mm. Os segmentos vertebrais foram submetidos a ensaios mecânicos de flexão, flexão lateral e torção em máquina universal de ensaio. Os parâmetros analisados foram força máxima (N e o momento (Nm para produzir uma deflexão preestabelecida. RESULTADOS: Não foi observada em todos os grupos experimentais diferença estatística dos valores da força máxima (N e do momento (Nm, entre as diferentes alturas (3,0mm e 6,0mm do enxerto ósseo intersomático. Conclusões: A estabilidade mecânica imediata da artrodese cervical monossegmentar anterior não sofreu influência da altura do enxerto ósseo intersomático nos ensaios de flexão, flexão lateral e torção.OBJECTIVE: To perform an experimental study of the impact of intersomatic bone graft height of the cervical spine on the mechanical stability of anterior cervical fixation. METHODS: Mechanical assays were performed using swine cervical spine (C3-C4. Three experimental groups were formed with 20 cervical spine segments (C3-C4 according to the degree

  15. Single-stage posterior debridement combined with bone grafting and internal fixation in treatment of thoracic spinal tuberculosis through Wiltse approach%一期后路经Wiltse入路病灶清除植骨内固定术治疗胸椎椎体结核

    Institute of Scientific and Technical Information of China (English)

    郑燕平; 田永昊; 刘新宇; 王磊; 王竹青; 李康

    2012-01-01

    Objective To investigate the feasibility and clinical outcomes of single-stage posterior debridement combined with bone grafting and internal fixation in treatment of thoracic spinal tuberculosis within anterior column through Wiltse approach. Methods From May 2009 to February 2012, 12 patients with thoracic spinal tuberculosis were treated with single-stage posterior debridement and bone grafting and internal fixation in this study. There were 8 males and 4 females with an average age of 46. 1 years. The mean disease duration was 16 months. The involved vertebral body ranged from T4 to T12 , including single segment in 3 cases, 2 segments in 5 cases, and 3 segments in 4 cases. The kyphosis Cobb' s angle was 20° ± 15° before operation. According to Frankel classfication for spinal cord injury, 5 cases were classified as grade E, 4 case as grade D, and 3 cases as grade C. Preoperative visual analogue scale ( VAS ) score was 5. 9 ±1. 1. Results All incisions achieved primary healing. All patients were followed up for 15.4 months on average. According to Frankel classification, 10 cases were classified as grade E and 2 cases as grade D at the final follow-up and VAS score was 1. 9 ± 1. 1. No loosening, emersion and breakage of internal fixation or complications occurred 1 year after operation. Conclusion Single-stage posterior debridement and bone grafting and internal fixation through Wiltse approach is safe and effective in the treatment of thoracic spinal tuberculosis within anterior column.%目的 探讨一期后路经Wiltse入路病灶清除植骨内固定术治疗胸椎椎体结核的可行性及疗效.方法 2009年5月~2012年2月,收治胸椎结核患者12例,其中男8例,女4例;平均46.1岁;病程平均16个月.单节段受累3例,双节段5例,3个节段4例.术前后凸Cobb角20°±15°.脊髓损伤程度按Frankel分级:E级5例,D级4例,C级3例.疼痛视觉模拟量表(visual analogue scale,VAS)评分为 5.9±1.1.均接受一期后路经Wiltse

  16. Immunological Response to Biodegradable Magnesium Implants

    Science.gov (United States)

    Pichler, Karin; Fischerauer, Stefan; Ferlic, Peter; Martinelli, Elisabeth; Brezinsek, Hans-Peter; Uggowitzer, Peter J.; Löffler, Jörg F.; Weinberg, Annelie-Martina

    2014-04-01

    The use of biodegradable magnesium implants in pediatric trauma surgery would render surgical interventions for implant removal after tissue healing unnecessary, thereby preventing stress to the children and reducing therapy costs. In this study, we report on the immunological response to biodegradable magnesium implants—as an important aspect in evaluating biocompatibility—tested in a growing rat model. The focus of this study was to investigate the response of the innate immune system to either fast or slow degrading magnesium pins, which were implanted into the femoral bones of 5-week-old rats. The main alloying element of the fast-degrading alloy (ZX50) was Zn, while it was Y in the slow-degrading implant (WZ21). Our results demonstrate that degrading magnesium implants beneficially influence the immune system, especially in the first postoperative weeks but also during tissue healing and early bone remodeling. However, rodents with WZ21 pins showed a slightly decreased phagocytic ability during bone remodeling when the degradation rate reached its maximum. This may be due to the high release rate of the rare earth-element yttrium, which is potentially toxic. From our results we conclude that magnesium implants have a beneficial effect on the innate immune system but that there are some concerns regarding the use of yttrium-alloyed magnesium implants, especially in pediatric patients.

  17. Salvage of infected total knee arthroplasty with Ilizarov external fixator

    Directory of Open Access Journals (Sweden)

    Venkata Gurava Reddy

    2011-01-01

    Full Text Available Background: Knee arthrodesis may be the only option of treatment in cases of chronic infected total knee arthroplasty (TKA with concomitant irreparable extensor mechanism disruption, extensive bone loss or severe systemic morbidities. Circular external fixation offers possible progressive adjustment to stimulate the bony fusion and to make corrections in alignment. We evaluated the results of knee arthrodesis with one or two stage circular external fixator for infected TKA. Materials and Methods: 16 cases of femoro-tibial fusion were retrospectively evaluated. Male-to-female ratio was 10:6. Mean age of the patients was 62.2 years. Cierney-Mader classification was used for anatomical and physiological evaluation while the bone stock deficiency was classified into mild, moderate and severe. Surgical technique involved either single or two stage arthrodesis using circular external fixator. Results: Union was achieved in 15 patients (93.75%. The mean duration for union (frame application time in these patients was 28.33 weeks (range 22 to 36 weeks. Analysis showed that in the group with frame application time of less than 28 weeks, the incidence of mild to moderate bone deficiency was 83.33%, while in the frame application time more than 28 weeks group the incidence was 20% (P-value 0.034. Similarly the incidence of Cierney-Mader 4B (Bl, Bs, Bls was found to be 33.33% in the group of frame application time of less than 28 weeks, while it was 90% in the group with frame application time more than 28 weeks (P-value 0.035. Conclusion: Circular external fixator is a safe and reliable method to achieve knee arthrodesis in cases of deep infection following TKA. Severe bone stock deficiency and Cierney- Mader type B host are likely risk factors for prolonged frame application time. We recommend a two-stage procedure especially when there is compromised host or severe bone loss.

  18. Green and biodegradable electronics

    Directory of Open Access Journals (Sweden)

    Mihai Irimia-Vladu

    2012-07-01

    Full Text Available We live in a world where the lifetime of electronics is becoming shorter, now approaching an average of several months. This poses a growing ecological problem. This brief review will present some of the initial steps taken to address the issue of electronic waste with biodegradable organic electronic materials. Many organic materials have been shown to be biodegradable, safe, and nontoxic, including compounds of natural origin. Additionally, the unique features of such organic materials suggest they will be useful in biofunctional electronics; demonstrating functions that would be inaccessible for traditional inorganic compounds. Such materials may lead to fully biodegradable and even biocompatible/biometabolizable electronics for many low-cost applications. This review highlights recent progress in these classes of material, covering substrates and insulators, semiconductors, and finally conductors.

  19. Augmented fixation of mandibular fractures with a threaded Kirschner wire.

    Science.gov (United States)

    Coniglio, J U; Norante, J D

    1989-06-01

    The maxillofacial surgeon uses a variety of techniques when treating mandibular fractures. The aim of treatment is to restore structure and function while minimizing morbidity. This requires adequate anatomic reduction and immobilization. The surgeon's choice of techniques should be safe, simple, economic, and effective. In this article, we discuss a previously described, yet little known, technique that fulfilled these criteria. The technique of augmented fixation of mandibular fractures using a threaded basal Kirschner wire was successfully used in seven patients. It offered the distinct advantage of rigid basal fixation that augmented interosseous and maxillomandibular fixation techniques. It was especially effective in stabilizing and promoting bone healing in unfavorable comminuted parasymphyseal fractures. Its ease and rapidity of application from readily available materials made it an effective alternate to elaborate techniques such as compression-plating systems. PMID:2719828

  20. Clinical Observation on Anterior Cervical Decompression and Bone Graft Fusion with Locking Plate Internal Fixation in Treatment of Cervical Spinal Cord Injury without Fracture and Dislocation%颈前路减压植骨融合带锁钛板内固定治疗无骨折脱位型颈脊髓损伤的临床探讨

    Institute of Scientific and Technical Information of China (English)

    孙海中

    2016-01-01

    Objective To discuss the effect of anterior cervical decompression and bone graft fusion with locking plate inter-nal fixation in treatment of cervical spinal cord injury without fracture and dislocation (SCIWORA). Methods 60 cases of patients with SCIWORA treated in our hospital from March 2011 to March 2014 were selected as the research object and randomly divided into two groups, the control group were given anterior cervical decompression and bone graft treatment, and the observation group were given anterior cervical decompression and bone graft fusion with locking plate internal fixa-tion treatment, both groups were scored by Japan department of orthopedics association (JOA)before and after operation, and the improvement rates of clinical symptoms after operation and the intervertebral fusion rates after half a year of the two groups were evaluated. Results Six months later after operation, the intervertebral fusion rate in the observation group was obviously higher than that in the control group (96.67%vs 80.0%), the difference was statistically significant (P<0.05), the JOA scores after three months of operation and six months of operation in the observation group were respectively (12.38± 1.69)points and (15.96±2.33)points, which were obviously higher than those in the control group, and the differences were statistically significant (P<0.05). Conclusion The curative effect of anterior cervical decompression and bone graft fusion with locking plate internal fixation in treatment of SCIWORA is definite.%目的 探讨颈前路减压植骨融合带锁钛板内固定治疗无骨折脱位型颈脊髓损伤(SCIWORA)的效果. 方法 整群选取该院2011年3月—2014年3月收治的无骨折脱位型颈脊髓损伤(SCIWORA)患者60例作为研究对象,采用数字随机对照表将患者分为对照组和观察组,对照组行颈前路减压植骨融合术治疗,观察组在对照组基础上加锁钛板内固定治疗,手术前后均行日本骨科协

  1. Clinical Observation on Anterior Cervical Decompression and Bone Graft Fusion with Locking Plate Internal Fixation in Treatment of Cervical Spinal Cord Injury without Fracture and Dislocation%颈前路减压植骨融合带锁钛板内固定治疗无骨折脱位型颈脊髓损伤的临床探讨

    Institute of Scientific and Technical Information of China (English)

    孙海中

    2016-01-01

    目的 探讨颈前路减压植骨融合带锁钛板内固定治疗无骨折脱位型颈脊髓损伤(SCIWORA)的效果. 方法 整群选取该院2011年3月—2014年3月收治的无骨折脱位型颈脊髓损伤(SCIWORA)患者60例作为研究对象,采用数字随机对照表将患者分为对照组和观察组,对照组行颈前路减压植骨融合术治疗,观察组在对照组基础上加锁钛板内固定治疗,手术前后均行日本骨科协会(JOA)评分,评估两组术后临床症状好转率及半年后植骨融合率.结果 观察组术后半年后植骨融合率为96.67%显著高于对照组80.0%,差异具有统计学意义(P<0.05);观察组术后3、6个月JOA评分分别为(12.38±1.69)分、(15.96±2.33)分均显著高于对照组,差异具有统计学意义(P<0.05). 结论 颈前路减压植骨融合带锁钛板内固定治疗SCIWORA疗效确切.%Objective To discuss the effect of anterior cervical decompression and bone graft fusion with locking plate inter-nal fixation in treatment of cervical spinal cord injury without fracture and dislocation (SCIWORA). Methods 60 cases of patients with SCIWORA treated in our hospital from March 2011 to March 2014 were selected as the research object and randomly divided into two groups, the control group were given anterior cervical decompression and bone graft treatment, and the observation group were given anterior cervical decompression and bone graft fusion with locking plate internal fixa-tion treatment, both groups were scored by Japan department of orthopedics association (JOA)before and after operation, and the improvement rates of clinical symptoms after operation and the intervertebral fusion rates after half a year of the two groups were evaluated. Results Six months later after operation, the intervertebral fusion rate in the observation group was obviously higher than that in the control group (96.67%vs 80.0%), the difference was statistically significant (P<0.05), the JOA scores after three

  2. Treatment of Gustilo grade Ⅲ leg fractures by external fixation associated with limited internal fixation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-qiang; ZHENG Hong-yu; WANG Bing; HUANG He; HE Fei; ZHAO Xue-ling

    2010-01-01

    Objective: To explore the clinical ef-fects of external fixation associated with limited internal fixa-tion on treatment of Gustilo grade Ⅲ leg fractures.Methods: From July 2006 to December 2008, 40 cases of Gustilo grade Ⅲ leg fiactures were emergently treated in our unit with external fixation frames.Soft tissue injuries were grouped according to the Gustilo classification as ⅢA in 17 cases, ⅢB in 13 cases, and ⅢC in 10 cases.All the patients were debrided within 8 hours, and then fracture reposition was preformed to reestablish the leg alignment.Limited internal fixation with plates and screws were per-formed on all the Gustilo Ilia cases and 10 Gustilo ⅢB cases at the first operation.But all the Gustilo ⅢC cases and 3 Gustilo ⅢB cases who had severe soft tissue injuries and bone loss only received Vacuum-sealing drainage (VSD).Broad-spectrum antibiotics were regularly used and VSD must be especially maintained easy and smooth for one week or more after operation.Limited internal fixation and transplanted free skin flaps or adjacent musculocutaneous flaps were not used to close wounds until the conditions of the wounds had been improved.Results: The first operations were completed within 90-210 minutes (170 minutes on average).The blood trans-fusions were from 400 ml to 1500 ml (those used for anti-shock preoperatively not included).All the 40 patients in this study were followed up for 6-28 months, 20.5 months on average.The lower limb function was evaluated accord-ing to the comprehensive evaluation standards of leg func-tion one year after operation and the results of 28 cases were excellent, 9 were good and 3 were poor.Conclusion: External fixation associated with limited internal fixation to treat Gustilo grade Ⅲ leg fractures can get satisfactory early clinical therapeutic effects.

  3. Editorial: Biodegradable Materials

    Directory of Open Access Journals (Sweden)

    Carl Schaschke

    2014-11-01

    Full Text Available This Special Issue “Biodegradable Materials” features research and review papers concerning recent advances on the development, synthesis, testing and characterisation of biomaterials. These biomaterials, derived from natural and renewable sources, offer a potential alternative to existing non-biodegradable materials with application to the food and biomedical industries amongst many others. In this Special Issue, the work is expanded to include the combined use of fillers that can enhance the properties of biomaterials prepared as films. The future application of these biomaterials could have an impact not only at the economic level, but also for the improvement of the environment.

  4. Eighth international congress on nitrogen fixation

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This volume contains the proceedings of the Eighth International Congress on Nitrogen Fixation held May 20--26, 1990 in Knoxville, Tennessee. The volume contains abstracts of individual presentations. Sessions were entitled Recent Advances in the Chemistry of Nitrogen Fixation, Plant-microbe Interactions, Limiting Factors of Nitrogen Fixation, Nitrogen Fixation and the Environment, Bacterial Systems, Nitrogen Fixation in Agriculture and Industry, Plant Function, and Nitrogen Fixation and Evolution.

  5. Ectopic Osteogenesis and Scaffold Biodegradation of Nano-Hydroxyapatite-Chitosan in a Rat Model

    OpenAIRE

    He, Yiqun; Dong, Youhai; Cui, Fuzhai; Chen, Xujun; Lin, Rongqiang

    2015-01-01

    The bone-formation and scaffold-biodegradation processes have not been fully characterized. This study aimed to determine the osteogenic ability of nHA-CS osteo-induced bone marrow mesenchymal stem cell (BMSC) composites and to explore the relationship between bone formation and scaffold biodegradation. The nHA-CS osteo-induced BMSC composites (nHA-CS+cells group) and the nHA-CS scaffolds (nHA-CS group) were implanted into the femoral spatium intermusculare of SD rats. At 2, 4, 6, 8, and 12 w...

  6. 聚甲基丙烯酸甲酯和自体骨加强的椎弓根螺钉技术治疗退变性脊柱侧凸的临床疗效比较%Autogenous bone and polymethylmethacrylate augmentation of screw fixation for degenerative scoliosis

    Institute of Scientific and Technical Information of China (English)

    谢杨; 傅强; 陈自强; 石志才; 朱晓东; 孙晓飞; 李明

    2012-01-01

    Objective To compare the clinical effect of autogenous bone and polymethylmethacrylate (PMMA) augmentation of screw fixation in degenerative scoliosis with osteoporosis. Methods A retrospective analysis was conducted on 31 consecutive patients with degenerative scoliosis combined with osteoporosis who accepted pedicle screw fixation from December 2000 to December 2006. Fourteen of them underwent fixation with pedicle screw by augmentation with PMMA and the other 17 patients with autogenous bone. Peri-operative data were recorded. Preoperative, postoperative and final follow up corrective effects were compared. Results No significant difference was found in clinical data except for administration time of oral pain relief medicines and surgery cost between the two surgical strategies. Cement leakage was observed in 2 patients in PMMA augmentation group, but there was no evidence of nerve damage. Conclusion There is no difference in surgical effect between two surgery strategies on degenerative scoliosis combined with osteoporosis. Less oral pain medicines are taken in the polymethylmethacrylate-augmented pedicle screw fixation and fusion, but with much more cost and danger of cement leakage.%目的 比较应用聚甲基丙烯酸甲酯( PMMA)和自体骨加强的椎弓根螺钉技术治疗合并骨质疏松的退变性脊柱侧凸的临床疗效.方法 回顾性分析2000年12月至2006年12月手术治疗的31例伴骨质疏松的退变性脊柱侧凸患者,其中14例采用PMMA加强钉道,17例采用自体骨加强钉道.记录并发症等围手术期情况,比较手术前后及随访期间侧凸的矫正效果.结果 两种手术除口服止痛药使用时间和手术费用外,其他临床数据差异无统计学意义,PMMA加强组中2例出现骨水泥渗漏,但未出现神经损伤的症状.结论 两种手术对伴骨质疏松的退变性脊柱侧凸的临床疗效无明显差异,PMMA加强的椎弓根螺钉内固定融合术可减少口服止痛药的用量,

  7. A biodegradable porous composite scaffold of PCL/BCP containing Ang-(1-7 for bone tissue engineering Um suporte compósito poroso biodegradável de PCL/BCP contendo Ang-(1-7 para engenharia de tecido ósseo

    Directory of Open Access Journals (Sweden)

    F. A. Macedo

    2012-12-01

    Full Text Available Highly porous three-dimensional biodegradable scaffolds was obtained from beta-tricalcium phosphate-hydroxyapatite bioceramic (BCP, PCL, and Angiotensin-(1-7. We used the solvent casting and particulate leaching methods (SC/PL. The processed scaffolds were characterized by X-ray microtomography (µ-CT. Biocompatibility tests in vitro were performed during three and seven days using MTT and Alkaline Phosphatase Activity (APA assays. Both the MTT activity and APA were evaluated using a one-way ANOVA test. The µ-CT results showed that the increase of the PCL:BCP weight ratio leads to structures with lower pore sizes. The pore interconnectivity of the processed scaffolds was evaluated in terms of the fragmentation index (FI. We observed that the obtained composites present poorly connected structures, with close values of FI. However, as the polymer phase is almost transparent to the X-rays, it was not taken into consideration in the µ-CT tests. The MTT activity assay revealed that scaffolds obtained with and without Angiotensin-(1-7 present mild and moderate cytotoxic effects, respectively. The APA assay showed that the rat osteoblasts, when in contact for three days with the PCL composites, presented an APA similar to that observed for the control cells. Nevertheless, for an incubation time of seven days we observed a remarkable decrease in the alkaline phosphatase activity. In conclusion, using the solvent casting and salt leaching method we obtained 3D porous that are composites of PCL, BC and Ang-(1-7, which have suitable shapes for the bone defects, a high porosity and interconnect pores. Furthermore, the viability in vitro showed that the scaffolds have potential for drug delivery system and could be used in future in vivo tests.A estrutura de um biomaterial para regeneração óssea é fator chave para seu sucesso clínico. Não existe um único biomaterial usado para reparo e regeneração óssea capaz de preencher todos os requisitos

  8. Fixation by active accommodation

    Science.gov (United States)

    Pahlavan, Kourosh; Uhlin, Tomas; Eklundh, Jan-Olof

    1992-11-01

    The field of computer vision has long been interested in disparity as the cue for the correspondence between stereo images. The other cue to correspondence, blur, and the fact that vergence is a combination of the two processes, accommodative vergence and disparity vergence, have not been equally appreciated. Following the methodology of active vision that allows the observer to control all his visual parameters, it is quite natural to take advantage of the powerful combination of these two processes. In this article, we try to elucidate such an integration and briefly analyze the cooperation and competition between accommodative vergence and disparity vergence on one hand and disparity and blur stimuli on the other hand. The human fixation mechanism is used as a guide-line and some virtues of this mechanism are used to implement a model for vergence in isolation. Finally, some experimental results are reported.

  9. Feasibility of low anterior cervical approach decompression and bone graft fusion for internal fixation in the treatment of patients with spine and spinal cord trauma in cervicothoracic junction%低位颈前入路减压植骨融合内固定治疗颈胸段脊柱脊髓损伤的可行性

    Institute of Scientific and Technical Information of China (English)

    刘明明; 程建; 华臻

    2015-01-01

    Objective:To explore the feasibility of low anterior cervical approach decompression and bone graft fusion for internal fixation in the treatment of patients with spine and spinal cord trauma in cervicothoracic junction.Methods:20 patients with spine and spinal cord trauma in cervicothoracic junction were selected.All patients were treated with low anterior cervical approach decompression and bone graft fusion for internal fixation.We discussed the efficacy and postoperative recovery of the patients. Results:All patients recovered well,and there was no case with loosening of the screws,loss of the titanium plate,the fracture of the titanium plate and other circumstances.Only 1 case with the position of titanium mesh not well fixed when detected by X tablets after operation.It has been adjusted after six months of surgery,after 1 year of operation,it recovered well,no titanium mesh moved. Conclusion:Patients with spine and spinal cord trauma in cervicothoracic junction with low anterior cervical approach decompression and bone graft fusion and internal fixation for the treatment can effectively promote the patients with cervicothoracic spine sequence returned to normal,and improve the patients' postoperative recovery.%目的:探讨低位颈前入路减压植骨融合内固定治疗颈胸段脊柱脊髓损伤的可行性。方法:收治颈胸段脊柱脊髓损伤患者20例,实施低位颈前入路减压植骨融合内固定治疗,对术后疗效及恢复情况进行探讨。结果:所有患者恢复良好,无一例患者出现螺钉松动、脱落、钛板断裂等情况,只有1例在术后经过X片检测后发现其钛网位置固定不佳,术后0.5年对其进行了调整,术后1年检测见其恢复良好,没有出现钛网移动情况。结论:颈胸段脊柱脊髓损伤患者采用低位颈前入路减压植骨融合内固定治疗,可以有效促进患者颈胸段脊柱序列恢复正常,改善患者的术后恢复情况。

  10. Investigation of the effects of treating spinal tuberculosis with the way of extraperitoneal debridement and posterior bone graft fixation%经腹膜外病灶清除植骨一期后路内固定术治疗脊柱结核的效果

    Institute of Scientific and Technical Information of China (English)

    何生; 谢造福; 邹尚浏; 黄少辉

    2012-01-01

    Objective To investigate the effects of treating spinal tuberculosis with the way of extraperitoneal debridement and posterior bone graft fixation. Methods 43 patients with spinal tuberculosis, who received the treatment of extraperitoneal debridement and posterior bone graft fixation, were selected to follow up for 6 ~23 months. The status of spinal cord injury and the angle of kyphosis before and after surgery were examined carefully. The cure rate was evaluated as well. Results ASIA classification of spinal cord function was evaluated, there were 21 cases for the E level and 10 cases for the D level before surgery. Except for one recovered to the D level, the rest of them recovered to the E level. There were significant differences statistically in the spinal cord function (P < 0.01) before and after surgery. After the last follow-up, the angulation of kyphosis and scoliosis was corrected in varying degrees. Physiologic curve restoration was well. Compared with preoperative, the Cobb angle changed significantly (P < 0.01). Evaluated by Mehtaet standards, 41 cases were cured and the cure rate was 95.34%. Conclusion The way of extraperitoneal debridement and posterior bone graft fixation is effective for treatment of spinal tuberculosis.%目的:探讨经腹膜外病灶清除植骨一期后路内固定术治疗脊柱结核的效果.方法:43例脊柱结核患者,采用腹膜外病灶清除植骨一期后路内固定术治疗,随访6 ~ 23个月,评价患者术前、术后末次脊髓损伤情况和脊柱后凸畸形角度,并评定治愈标准.结果:术前脊髓神经功能ASIA分级有21例为E级,10例为D级;末次随访ASIA分级脊髓神经功能除1例恢复为D级外,其余的均恢复为E级,术前和术后末期随访脊髓神经功能ASIA分级情况有在统计学上差异非常显著(P<0.01).术后末次随访,脊柱后凸、侧凸成角均有不同程度纠正,生理弧度恢复并保持满意,术后末次随访Cobb角度与术前比

  11. 骨水泥强化椎弓根钉固定联合椎体成形术治疗重度骨质疏松性脊柱骨折%Pedicle screw fixation strengthened with bone cement combined with vertebroplasty for the treatment of severe osteoporotic fractures

    Institute of Scientific and Technical Information of China (English)

    胡明; 李大伟; 黄凤山; 刘玉川; 杨达宇; 马远征

    2011-01-01

    Objective To explore the peri-operative treatment and clinical efficacy of pedicle screw fixation strengthened with bone cement combined with vertebroplasty for the treatment of severe osteoporotic fractures. Methods The clinical data of 15 patients with severe vertebral osteoporotic compression fractures were retrospectively analyzed from August 2005 to April 2009. The average age of the patients was 63. 1 years old. They had no severe basal diseases. They were all treated with posterior pedicle screw fixation strengthened with bone cement combined with vertebroplasty. All patients were followed up for 10-38 months (21 months in average) after the operation. Results All patients could tolerate the surgery and the average operating time was 106. 7 ±5. 3 min. The average bleeding volume was 370 ± 6. 1 ml. The twist and back pain were significantly ameliorated after the surgery. The height of vertebral body recovered back to 90% after operation. The height loss was not obvious during the following up. Conclusion The efficacy of pedicle screw fixation strengthened with bone cement combined with vertebroplasty for the treatment of severe osteoporotic fractures is good at correcting fracture and maintaining the recovering effect of the vertebra. The key point of this therapy is the surgical indication and osteoporotic medicine treatment.%目的 探讨骨水泥强化椎弓根钉固定联合椎体成形术治疗严重骨质疏松性椎体压缩骨折的围术期处理和临床疗效.方法 回顾分析2005年8月~ 2009年4月收治的15例严重骨质疏松性椎体压缩骨折患者的临床资料,平均63.1岁,无重大基础病存在,经脊柱后入路椎弓根钉撑开复位,钉道采用骨水泥灌注加强并行经伤椎椎体成形术.术后随访10~ 38个月,平均21月.结果 均耐受手术,平均手术时间为106.7±5.3min;平均失血量为370±6.1ml,术后腰背痛明显改善,椎体高度恢复至90%左右,随访椎体高度

  12. External fixation for the treatment of open fractures of the proximal humerus caused by firearms

    Directory of Open Access Journals (Sweden)

    Mirić Dragan

    2004-01-01

    Full Text Available Nine patients with open fractures of the proximal humerus were treated using an external fixation device. All of them had grade III open fractures resulting from high-velocity missile and explosive injuries with massive foreign body contamination. Radial nerve injury was present in five and two multiply injuried patients with thoracic wall and abdominal viscera were present. There were no major arterial injuries. Chronic osteitis with fistula and sequestra developed in one. There were no nonunions and no refractures. Minor painless limitation of shoulder and elbow motion presented in all patient. Upper-third humeral open fractures due to firearms are a unique type of open fractures. They are usually highly comminuted therefore, stable fixation is difficult or impossible to achieve. On the other hand, the risk of infection is high following plate fixation. External fixation allows adequate management of the soft tissue wounds, provides stable bone fixation and allows early mobilization of the shoulder and elbow.

  13. Biomechanical Comparison of 2 Different Locking Plate Fixation Methods in Vancouver B1 Periprosthetic Femur Fractures

    OpenAIRE

    Pletka, Joshua D.; Marsland, Daniel; Belkoff, Stephen M.; Mears, Simon C.; Kates, Stephen L.

    2011-01-01

    Locking plates are commonly used to treat fractures around a well-fixed femoral component. The optimal construct should provide sufficient fixation while minimizing soft-tissue dissection. The purpose of the current study was to determine whether plate length, working length, or bone mineral density affects survival of locking plate fixation for Vancouver type B1 periprosthetic hip fractures. A transverse osteotomy was created just distal to cemented femoral prostheses in 9 pairs of cadaveric...

  14. Strength analysis of clavicle fracture fixation devices and fixation techniques using finite element analysis with musculoskeletal force input.

    Science.gov (United States)

    Marie, Cronskär

    2015-08-01

    In the cases, when clavicle fractures are treated with a fixation plate, opinions are divided about the best position of the plate, type of plate and type of screw units. Results from biomechanical studies of clavicle fixation devices are contradictory, probably partly because of simplified and varying load cases used in different studies. The anatomy of the shoulder region is complex, which makes it difficult and expensive to perform realistic experimental tests; hence, reliable simulation is an important complement to experimental tests. In this study, a method for finite element simulations of stresses in the clavicle plate and bone is used, in which muscle and ligament force data are imported from a multibody musculoskeletal model. The stress distribution in two different commercial plates, superior and anterior plating position and fixation including using a lag screw in the fracture gap or not, was compared. Looking at the clavicle fixation from a mechanical point of view, the results indicate that it is a major benefit to use a lag screw to fixate the fracture. The anterior plating position resulted in lower stresses in the plate, and the anatomically shaped plate is more stress resistant and stable than a regular reconstruction plate. PMID:25850983

  15. CEPHALOMEDULLARYS FRACTURE FIXATION IN THE MANAGEMENT OF UNSTABLE HIP FRACTURES.

    Directory of Open Access Journals (Sweden)

    Fonseca-Caro John Fredy

    2015-12-01

    Full Text Available Introduction: unstable hip fractures in elderly people are a public health problem. The treatment is carried out with osteolysis and cephalomedullarys bone nails of which there are others designs. Objective: to determine in the clinical results whether there are differences between PF Targon bone nails and TFN spiral plate. Methods: prospective study was carried out in 69 patients who presented unstable intertrochanteric fracture. The patients were taken to surgery for osteosynthesis with cephalomedullarys bone nails. They were divided in two groups: [A] Two screws fixation in neck (PF Targon and [B] (TFN spiral plate. For both groups were performed by conventional surgical technique and evaluated the surgical time, the bleeding, the intraoperative complications, the functionality results, clinical and radiological consolidation. Results: the procedure was followed in an average of 23 months. No differences were observed in the return of functionality between the use of an implant or other. Complications with Cut Out were more frequent and PF Targon not in the right position without significant difference. Surgical time was lower with TFN, 62.4 ± 15.7 minutes, while with Targon-PF was 86.5 ± 31.7 minutes p<0.0002. Conclusion: no significant differences were observed in the clinical results between the use of PF Targon bone nails and TFN spiral plate. Rev. cienc.biomed. 2015;6(2:265-271 KEY WORDS Bone Nails, Fracture Fixation, Hip.

  16. Analysis and an overview of fixators in medicine and the methods of processing materials for producing fixators

    OpenAIRE

    Dalibor Milojko Đenadić; Miodrag T. Manić; Dejan I. Tanikić; Saša S. Ranđelović; Petar S. Đekić

    2013-01-01

    The fixator is a medical device that provides support to fractured biological structures. Metal biomaterials are mainly used for replacing broken or damaged hard tissues such as bones because of their high strenght, toughness and corrosion resistance. Materials such as stainless steel, titanium and aluminium alloys (Ti-6Al-4V), cobalt and chromium alloys, composite materials and other biocompatible materials are used in orthopedy for the stabilization of connective tissue injuries or as a sub...

  17. Prediction at long-term condyle screw fixation of temporomandibular joint implant: A numerical study.

    Science.gov (United States)

    Ramos, A; Duarte, R J; Mesnard, M

    2015-05-01

    The fixation of commercial temporomandibular joint (TMJ) implant is accomplished by using screws, which, in some cases, can lead to loosening of the implant. The aim of this study was to predict the evolution of fixation success of a TMJ. Numerical models using a Christensen TMJ implant were developed to analyze strain distributions in the adjacent mandibular bone. The geometry of a human mandible was developed based on computed tomography (CT) scans from a cadaveric mandible on which a TMJ implant was subsequently placed. In this study, the five most important muscle forces acting were applied and the anatomical conditions replicated. The evolution of fixation was defined according to bone response methodology focused in strain distribution around the screws. Strain and micromotions were analyzed to evaluate implant stability, and the evolution process conduct at three different stages: start with all nine screws in place (initial stage); middle stage, with three screws removed (middle stage), and end stage, with only three screws in place (final stage). With regard to loosening, the implant success fixation changed the strains in the bone between 21% and 30%, when considering the last stage. The most important screw positions were #1, #7, and #9. It was observed that, despite the commercial Christensen TMJ implant providing nine screw positions for fixation, only three screws were necessary to ensure implant stability and fixation success. PMID:25819477

  18. Local delivery of zoledronate from a poly (D,L-lactide)-Coating increases fixation of press-fit implants.

    Science.gov (United States)

    Jakobsen, Thomas; Bechtold, Joan E; Søballe, Kjeld; Jensen, Thomas; Greiner, Stefan; Vestermark, Marianne T; Baas, Jørgen

    2016-01-01

    Early secure fixation of total joint replacements is crucial for long-term survival. Antiresorptive agents such as bisphosphonates have been shown to increase implant fixation. We investigated whether local delivery of zoledronate from poly-D, L-lactide (PDLLA)-coated implants could improve implant fixation and osseointegration. Experimental titanium implants were bilaterally inserted press-fit into the proximal tibiae of 10 dogs. On one side the implant was coated with PDLLA containing zoledronate. The contralateral implant was uncoated and used as control. Observation period was 12 weeks. Implant fixation was evaluated with histomorphometry and biomechanical push-out test. We found an approximately twofold increase in all biomechanical parameters when comparing data from the zoledronate group with their respective controls. Histomorphometry showed increased amount of preserved bone and increased bone formation around the zoledronate implants. This study indicates that local delivery of zoledronate from a PDDLA coating has the potential to increase implant fixation. PMID:26177742

  19. Preliminary study of biodegradation of AZ31B magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    REN Yibin; HUANG Jingjing; ZHANG Bingchun; YANG Ke

    2007-01-01

    Magnesium alloys are potential to be developed as a new type of biodegradable implant material by use of their active corrosion behavior.Both in vitro and in vivo biodegradation properties of an AZ31B magnesium alloy were investigated in this work.The results showed that AZ31B alloy has a proper degradation rate and much lower hydrogen release in Hank's solution,with a degradation rate of about 0.3 mm/year and hydrogen release below 0.15mL/cm2.The animal implantation test showed that the AZ31B alloy could slowly biodegrade in femur of the rabbit and form calcium phosphate around the alloy sample,with the Ca/P ratio close to the natural bone.

  20. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  1. Bone Grafts

    Science.gov (United States)

    A bone graft transplants bone tissue. Surgeons use bone grafts to repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some ...

  2. Absorbable and biodegradable polymers

    CERN Document Server

    Shalaby, Shalaby W

    2003-01-01

    INTRODUCTION NOTES: Absorbable/Biodegradable Polymers: Technology Evolution. DEVELOPMENT AND APPLICATIONOF NEW SYSTEMS: Segmented Copolyesters with Prolonged Strength Retention Profiles. Polyaxial Crystalline Fiber-Forming Copolyester. Polyethylene Glycol-Based Copolyesters. Cyanoacrylate-Based Systems as Tissue Adhesives. Chitosan-Based Systems. Hyaluronic Acid-Based Systems. DEVELOPMENTS IN PREPARATIVE, PROCESSING, AND EVALUATION METHODS: New Approaches to the Synthesis of Crystalline. Fiber-Forming Aliphatic Copolyesters. Advances in Morphological Development to Tailor the Performance of Me

  3. Nursing of nail fixation combined with bone cement replantation treatment of femoral shaft nonunion.%交锁髓内钉固定结合骨泥回植治疗股骨干骨折不愈合的护理

    Institute of Scientific and Technical Information of China (English)

    柯阳芳; 邓月兴; 李文英; 黄瑞生; 樊仕才

    2009-01-01

    目的:探讨交锁髓内钉固定结合扩髓之骨泥回植治疗股骨干骨折不愈合的围手术期护理特点.方法:交锁髓内钉固定并将扩髓时产生的骨泥回植于骨折端治疗股骨干骨折不愈合29例,其中男23例,女6例.年龄26~54岁,平均39.5岁.术后48 h拔引流管,使用抗生素预防感染3 d,所有患者均未行外固定,摄X线片根据骨折稳定情况进行关节功能锻炼.结果:29例平均骨性愈合时间为47周,膝关节功能较术前明显改善,无感染、肢体短缩、旋转或成角畸形,无内固定断裂等并发症.结论:交锁髓内钉固定结合扩髓之骨泥回植治疗股骨干骨折不愈合,术前心理辅导、术前准备、术中配合监护、术后康复训练等环节护理对手术成功至关重要.%Objective:Discussion the characteristics of perioperative nursing of locked reamed intramedullary nailing for replantation of the bone cement treatment of femoral shaft fracture nonunion. Methods:Care line locked intramedullary reaming and nailing of the bone cement when replantation in the treatment of femoral shaft fracture nonunion in 29 cases, male 23 cases, six cases of women; age 26-54 years old, average 39.5 years old.After surgery 48h the drainage tube out, the use of antibiotics to prevent infection in 3 d, not all patients with external fixation line, taken X-ray conducted in accordance with the stability of articular fracture functional exercise.Results:Average of 29 cases of bone healing time for 47 weeks, pre-operative knee function improved significantly compared with no infection, limb shortening, rotation or angulation deformity, no complications such as fracture fixation. Conclusion:Locked reamed intramedullary nailing for replantation of the bone cement treatment of femoral shaft fracture nonunion of perioperative nursing, with emphasis on pre-operative psychological, preoperative preparation, intraoperative with guardianship, such as postoperative rehabilitation

  4. Biodegradation Study of Microcrystalline Chitosan and Microcrystalline Chitosan/β-TCP Complex Composites

    OpenAIRE

    Kinga Brzoza-Malczewska; Magdalena Kucharska; Bogdan Gruchała; Maria Wísniewska-Wrona; Luciano Pighinelli

    2012-01-01

    Bone repair or regeneration is a common and complicated clinical problem in orthopedic surgery. The importance of natural polymers, such as microcrystalline chitosan, and minerals such as HAp and β-TCP, has grown significantly over the last two decades due to their renewable and biodegradable source, increasing the knowledge and functionality of composites in technological and biomedical applications. This study compares the biodegradation process, bioactivity, structure, morphology, and mech...

  5. Atlantoaxial fixation: Overview of all techniques

    Directory of Open Access Journals (Sweden)

    Mummaneni Praveen

    2005-01-01

    Full Text Available Over the past century, steady advances have been made in fixating an unstable atlantoaxial complex. Current options for fixation of the atlantoaxial complex include posterior clamps, posterior wiring techniques, C1-C2 transarticular screw fixation, posterior C1 lateral mass screw with C2 pars or pedicle screw fixation, and anterior transoral C1 lateral mass to C2 vertebral body fixation.

  6. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    defect. CONCLUSIONS: Our findings suggested a new bioactive bone cement for prosthetic fixation in total joint replacement.

  7. Long-term release of clodronate from biodegradable microspheres

    OpenAIRE

    Perugini, Paola; Genta, Ida; Conti, Bice; Modena, Tiziana; Pavanetto, Franca

    2001-01-01

    This paper describes the formulation of a biodegradable microparticulate drug delivery system containing clodronate, a bisphosphonate intended for the treatment of bone diseases. Microspheres were prepared with several poly(D,L-lactide-co-glycolide) (PLGA) copolymers of various molecular weights and molar compositions and 1 poly(D,L-lactide) (PDLLA) homopolymer by a water-in-oil-in-water (w/o/w) double emulsion solvent evaporation procedure. Critical process parameters and formulation variabl...

  8. Volar, Intramedullary, and Percutaneous Fixation of Distal Radius Fractures.

    Science.gov (United States)

    Alluri, Ram; Longacre, Matthew; Pannell, William; Stevanovic, Milan; Ghiassi, Alidad

    2015-11-01

    Background The management of extra-articular distal radius fractures is highly variable, with no clear consensus regarding their optimal management. Purpose To assess comparatively the biomechanical stability of Kirschner wire (K-wire) fixation, volar plating, and intramedullary nailing for unstable, extra-articular distal radius fractures with both (1) constant and (2) cyclical axial compression, simulating forces experienced during early postoperative rehabilitation. Methods Twenty-six volar locking plate, intramedullary nail, and K-wire bone-implant constructs were biomechanically assessed using an unstable extra-articular distal radius bone model. Bone implant models were created for each type of construct. Three samples from each construct underwent compressive axial loading until fixation failure. The remaining samples from each construct underwent fatigue testing with a 50-N force for 2,000 cycles followed by repeat compressive axial loading until fixation failure. Results Axial loading revealed the volar plate was significantly stiffer than the intramedullary nail and K-wire constructs. Both the volar plate and intramedullary nail required greater than 300 N of force for fixation failure, while the K-wire construct failed at less than 150 N. Both the volar plate and intramedullary nail demonstrated less than 1 mm of displacement during cyclic loading, while the K-wire construct displaced greater than 3 mm. Postfatigue testing demonstrated the volar plate was stiffer than the intramedullary nail and K-wire constructs, and both the volar plate and intramedullary nail required greater than 300 N of force for fixation failure while the K-wire construct failed at less than 150 N. Conclusions Volar plating of unstable extra-articular distal radius fractures is biomechanically stiffer than K-wire and intramedullary fixation. Both the volar plate and intramedullary nail demonstrated the necessary stability and stiffness to maintain anatomic

  9. Fixador esquelético pino-resina acrílica e enxerto ósseo esponjoso no tratamento de complicações secundárias à imobilização inadequada de fratura do rádio e ulna em cães Acrylic-pin external fixator and cancellous bone graft in the treatment of complications caused by inadequate immobilization of radius and ulna fracture in dogs

    Directory of Open Access Journals (Sweden)

    Sheila Canevese Rahal

    2005-10-01

    Full Text Available O objetivo do estudo foi avaliar a eficácia do fixador esquelético pino-resina, configuração tipo II, coadjuvado pelo enxerto ósseo esponjoso autólogo, no tratamento das complicações secundárias à imobilização inadequada de fraturas do rádio e ulna em 10 cães, com peso entre 1,8 e 33,6 kg. Detectou-se não-união (n=4, osteomielite (n=1, má-união (n=1, falência ou quebra de implante (n=4, sendo 60% das lesões referente ao uso prévio de pino intramedular no rádio. A montagem do fixador foi realizada com transfixação de pinos lisos em sua maioria angulados, cujas extremidades excedentes foram dobradas e estabilizadas com resina acrílica. Em todos os casos, utilizou-se enxerto esponjoso autólogo fresco, após debridamento do foco de fratura. O tempo de permanência do aparelho variou entre 45 dias e 5 meses e a maior complicação foi o afrouxamento dos pinos transfixantes. A consolidação das fraturas ocorreu por formação de calo periosteal de mínimo a moderado, indicando boa rigidez da montagem.The aim of this study was to evaluate the acrylic-pin external fixator, type II-configuration, and cancellous bone autograft for treating complications of radius and ulna fractures in 10 dogs weighing between 1.8 and 33.6 kg. Nonunion (n=4, osteomyelitis (n=1, malunion (n=1, failure or breakage of implant (n=4 were detected, and 60 % of them were associated with previous intramedullary pin placement in the radius. The fixator frame was constructed using most of the smooth transfixation pins angled. The fixation rods were constructed by placing acrylic resin over the ends of the transfixation pins that were previously bent. In all cases fresh cancellous bone autograft was used after cleaning of the fracture site. The permanence time of the external fixator ranged from 45 days to 5 months, and the most important complication was pin loosening. Fracture healing was by minimal to moderate periosteal callus, suggesting good rigidity

  10. Fixation performance of an ultrasonically fused, bioresorbable osteosynthesis implant: A biomechanical and biocompatibility study.

    Science.gov (United States)

    Augat, P; Robioneck, P B; Abdulazim, A; Wipf, F; Lips, K S; Alt, V; Schnettler, R; Heiss, C

    2016-01-01

    Bioresorbable implants may serve as an alternative option for the fixation of bone fractures. Because of their minor inherent mechanical properties and insufficient anchorage within bone bioresorbable implants have so far been limited to mechanically nondemanding fracture types. By briefly liquefying the surface of the biomaterial during insertion, bioresorbable implants can be ultrasonically fused with bone to improve their mechanical fixation. The objective of this study was to investigate the biomechanical fixation performance and in vivo biocompatibility of an ultrasonically fused bioresorbable polymeric pin (SonicPin). First, we biomechanically compared the fused pin with press fitted metallic and bioresorbable polymeric implants for quasi-static and fatigue strength under shear and tensile loading in a polyurethane foam model. Second, fused implants were inserted into cancellous bovine bone and tested biomechanically to verify the reproducibility of their fusion behavior. Finally, the fused pins were tested in a lapine model of femoral condyle osteotomies and were histologically examined by light and transmission electron microscopy. While comparable under static shear loads, fixation performance of ultrasonically fused pins was significantly (p = 0.001) stronger under tensile loading than press fit implants and showed no pull-out. Both bioresorbable implants withstood comparable fatigue shear strength, but less than the K-wire. In bovine bone the ultrasonic fusion process worked highly reproducible and provided consistent mechanical fixation. In vivo, the polymeric pin produced no notable foreign body reactions or resorption layers. Ultrasonic fusion of polymeric pins achieved adequate and consistent mechanical fixation with high reproducibility and exhibits good short-term resorption and biocompatibility. PMID:25678144

  11. The clinical effect of treatment with external circular fixator in bone defect after tibial shaft fractures secondary infection%可调组合环小腿同步延长器治疗胫骨感染骨缺损的临床疗效观察

    Institute of Scientific and Technical Information of China (English)

    郑峰; 刘建宇

    2014-01-01

    analyze the clinical effectiveness,safety and significance of treatment with external circular fixator,through the relationship of inducible nitric oxide synthase (iNOS) and bone regeneration to further explore the mechanism of the molecular biology of bone lengthening at the same time.Methods Collected bone defect after tibial shaft fractures secondary infection who were treated with external circular fixator as study group (28 cases),all the cases fixed by external circular fixator,20 healthy volunteers as control group.Study group in different time point measured the levels of serum iNOS content,were compared with the control group.Results All patients were scheduled to reach the extremity lengthening and the bone defect were repaired and healed in study group.The bacterial culture results showed that 18 cases (64.29%,18/28) of resistant Staphylococcus aureus,5 cases (17.86%,5/28) of Hemolytic streptocaccus,2 cases (7.14%,2/28) ofP.aeruginosa,one case (3.57%,1/28) of drug-resistant Enterobacter cloacae,one case(3.57%,1/28) of Staphylococcus epidermidis,one case(3.57%,1/28) of Onion-like aeromonas,the proportion of the former two was significantly higher than other bacteria (P < 0.05).The levels of serum iNOS content 1 d after surgery in study group were increased,compared with control group,difference was no significant (P > 0.05).The levels of serum iNOS content 14 d after surgery,stoped extend,1 d stoped extend,3 d stoped extend in study group were significantly higher than those in control group [(118.8 ± 6.6) U/L vs.(86.4 ± 5.4) U/L,(136.2 ± 8.4) U/L vs.(88.2 ± 3.6) U/L,(132.6 ± 9.0) U/L vs.(87.6 ± 4.8) U/L,(103.8 ± 5.4) U/L vs.(86.4 ± 4.2) U/L] (P < 0.05),there was no significant difference between two groups in other times (P > 0.05).Conclusions External circular fixator for the repair and reconstruction effects in patients with bone defect can achieve the desired therapeutic goal,the higher expression of iNOS may be one of the

  12. Anterior transarticular screw fixation as a conventional operation for rigid stabilization

    Directory of Open Access Journals (Sweden)

    Manabu Sasaki

    2014-01-01

    Full Text Available Background: Anterior transarticular screw (ATS fixation is a useful surgical option for atlantoaxial (AA stabilization. This report presents a revised ATS method for AA fusion. Methods: A 79-year-old male presented with AA instability attributed both to an old odontoid fracture and severe degeneration of the lateral atlantoaxial joints (LAAJs. ATS fixation was performed through the conventional anterior cervical approach. The longest screw trajectories were planned preoperatively using multiplanar reconstruction computed tomography (CT scans, with entry points of the screws situated at the midpoint on the inferior border of the axial body. The surgical exposure was limited to opening at the entry points alone. Our retractor of choice was the Cusco speculum; it sufficiently secured space for utilizing the required instruments for screw placement while offering sufficient protection of soft tissues. Cannulated full-threaded bicortical screws stabilized the LAAJs. Screw insertion required a significant amount of coronal angulation up to the superior articular process of the atlas under open-mouth and lateral fluoroscopy image guidance. After ATS fixation, bone grafting was performed between the posterior laminae of the axis and the atlas through a conventional posterior approach. Results: Bony fusion between the atlas and the axis was confirmed radiographically. Arthrodesis of the LAAJs occurred despite no bone grafting. Conclusions: Rigid fixation of the LAAJs was obtained by our ATS technique, indicating that it is an alternative method for AA fixation when posterior rigid internal fixation is not applicable.

  13. 持续闭式引流(VSD)结合骨水泥抗生素链珠治疗腰椎骨折椎弓根钉棒系统内固定术后早期感染%Treatment of early postoperative infection of lumbar fracture internal fixation of pedicle screw rod system with vacuum sealing drainage(VSD)combined with antibiotic bone cement chain

    Institute of Scientific and Technical Information of China (English)

    朱余龙; 朱海涛; 丁德刚; 徐亮

    2014-01-01

    目的:探讨持续闭式引流(VSD)结合骨水泥抗生素链珠治疗腰椎骨折椎弓根钉棒系统内固定术后早期感染的临床疗效。方法2010年3月一2014年3月,使用持续闭式引流(VSD)结合骨水泥抗生素链珠治疗腰椎骨折椎弓根钉棒系统内固定术后早期感染11例,随访其临床效果。结果11例患者均得到随访,随访时间8—12月,平均10.5月。手术后感染治愈,无一例需取出原内固定物重新或者更换固定材料。结论持续闭式引流(VSD)结合骨水泥抗生素链珠治疗腰椎骨折椎弓根钉棒系统内固定术后早期感染操作简单、安全有效,可以作为治疗腰椎骨折椎弓根钉棒系统内固定术后早期感染手段之一。%Objective: To investigate the efficacy of the treatment of early postoperative infection of umbar fracture internal fixation of pedicle screw rod system with VSD combined with antibiotic bone cement chain. Methods: from 2010 March to 2014 March, the use of continuous closed drainage (VSD) combined with antibiotic bone cement bead chain, lumbar fracture internal fixation of pedicle screw rod system treatment of early postoperative infection in 11 cases, folow-up clinical results. Results: 11 patients were folowed up from 8-12 months, with an average of 8.5 months. Cured of infection after surgery, no case of need to remove or replace the original re-fixed within the implant material. Conclusion: The continuous closed drainage (VSD) combined with antibiotic bone cement beads chain to treat early infection is simple, safe and effective treatment of lumbar fracture internal fixation of pedicle screw rod system can be used as a means of early postoperative infection.

  14. Systemic alendronate treatment improves fixation of press-fit implants: a canine study using nonloaded implants

    DEFF Research Database (Denmark)

    Jensen, Thomas B; Bechtold, Joan E; Chen, Xinqian; Søballe, Kjeld

    2007-01-01

    Bone resorption associated with local trauma occurring during insertion of joint prostheses is recognized as an early event. Being an osteoclastic inhibitor, alendronate is a potential candidate means to decrease early periprosthetic bone resorption and thereby improve implant fixation. We...... investigated the influence of oral alendronate treatment on early implant fixation in two implant interface settings representing sites of an implant that are in contact with surrounding bone, and other sites without intimate bone contact. One plasma-sprayed cylindrical titanium implant (6 mm diameter) was...... inserted into each proximal tibia of 16 dogs. On one side the implant was inserted press-fit whereas on the contralateral side, the implants were surrounded by a 2 mm concentric gap. Oral alendronate (0.5 mg/kg/day) was given 2 weeks following surgery to eight dogs. The dogs were euthanized after 10 weeks...

  15. Bone Biopsy

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Bone Biopsy Bone biopsy uses a needle and imaging guidance ... limitations of Bone Biopsy? What is a Bone Biopsy? A bone biopsy is an image-guided procedure ...

  16. MANAGEMENT OF DISEASES OF LONG BONES WITH KUNTSCHER NAILS

    OpenAIRE

    Ravikant; Vibha; Singh,, G.; Srivastava

    2015-01-01

    BACKGROUND: AIMS: SETTINGS AND DESIGN : The aim of this study was, to devise economical, easy, simple, quick method of fixation of diseased long bones, so that pathological fracture could be prevented and to provide rigid fixation, in those cases which have already developed pathological fractu re, and to achieve arthrodesis. Ten, cases of long bone diseases were managed with the help of K nails, in the Department of Orthopaedics, in CIMS, between, December 2002 ...

  17. Orthopaedic Interface Tissue Engineering for the Biological Fixation of Soft Tissue Grafts

    OpenAIRE

    Moffat, Kristen L.; Wang, I-Ning Elaine; Rodeo, Scott A.; Lu, Helen H.

    2009-01-01

    Interface tissue engineering is a promising new strategy aimed at the regeneration of tissue interfaces and ultimately enabling the biological fixation of soft tissue grafts utilized in orthopaedic repair and sports medicine. Many ligaments and tendons with direct insertions into subchondral bone exhibit a complex enthesis consisting of several distinct yet continuous regions of soft tissue, noncalcified fibrocartilage, calcified fibrocartilage and bone. Regeneration of this multi-tissue inte...

  18. Fracture union and complication following internal fixation of clavicle by plate and screw

    OpenAIRE

    Bishnu Prasad Patro; Saroj Kumar Patra; Subrat Mohapatra

    2016-01-01

    Background: Among all long bones clavicle is the only bone placed horizontally and has membranous ossification. Clavicle fractures accounting for about 2.6% of total body fractures and 34% to 45% of total shoulder girdle injuries in adults. Most fractures occur in middle third of clavicle and common in young male patients. It has wide range of management from conservative to variant internal fixation. Each procedure has its own outcome and complications. We tried to find out the outcome and c...

  19. Monitoring Biodegradation of Magnesium Implants with Sensors

    Science.gov (United States)

    Zhao, Daoli; Wang, Tingting; Guo, Xuefei; Kuhlmann, Julia; Doepke, Amos; Dong, Zhongyun; Shanov, Vesselin N.; Heineman, William R.

    2016-04-01

    Magnesium and its alloys exhibit properties such as high strength, light weight, and in vivo corrosion that make them promising candidates for the development of biodegradable metallic implant materials for bone repair, stents and other medical applications. Sensors have been used to monitor the corrosion of magnesium and its alloys by measuring the concentrations of the following corrosion products: magnesium ions, hydroxyl ions and hydrogen gas. The corrosion characterization system with home-made capillary pH and Mg2+ microsensors has been developed for real-time detection of magnesium corrosion in vitro. A hydrogen gas sensor was used to monitor the corrosion of magnesium by measuring the concentration of the hydrogen gas reaction product in vivo. The high permeability of hydrogen through skin allows transdermal monitoring of the biodegradation of a magnesium alloy implanted beneath the skin by detecting hydrogen gas at the skin surface. The sensor was used to map hydrogen concentration in the vicinity of an implanted magnesium alloy.

  20. Preparation of a biodegradable oil absorber and its biodegradation.

    Science.gov (United States)

    Yoo, Su-Yong; Daud, Wan Mohd Ashri Wan; Lee, Min-Gyu

    2012-01-01

    The biodegradable oil absorption resin (B-PEHA) was prepared by suspension polymerization, and its preparation was confirmed by Fourier transform infrared analysis. The oil absorption capacities of the prepared B-PEHA were: chloroform 30.88, toluene 19.75, xylene, 18.78, THF 15.96, octane 11.43, hexane 9.5, diesel oil 12.80, and kerosene 13.79 g/g. The biodegradation of the prepared B-PEHA was also investigated by determination of reduced sugar produced after enzymatic hydrolysis, thermogravimetric analysis, and incubation with Aspergillus niger. The biodegradation of B-PEHA was ~18%. PMID:21909668

  1. Analysis and an overview of fixators in medicine and the methods of processing materials for producing fixators

    Directory of Open Access Journals (Sweden)

    Dalibor Milojko Đenadić

    2013-06-01

    Full Text Available The fixator is a medical device that provides support to fractured biological structures. Metal biomaterials are mainly used for replacing broken or damaged hard tissues such as bones because of their high strenght, toughness and corrosion resistance. Materials such as stainless steel, titanium and aluminium alloys (Ti-6Al-4V, cobalt and chromium alloys, composite materials and other biocompatible materials are used in orthopedy for the stabilization of connective tissue injuries or as a substitute for the bone tissues. Fixators are classified according to the place of installation to external and internal fixators. Widely used medical fixators are pins, rods plates, screws, pipes, wires, nails and external fixators. Conventional and non-conventional methods of processing are used in the production process for all types of fixators. Introduction Fixators are medical devices manufactured to support damaged biological structures. In the field of orthopedic surgery that deals with skeletal disorders such as bone, spine, joints, muscles and tendons injuries and diseases, various metals, titanium and cobalt alloys etc. are used to stabilize the supporting tissue injuries or as a substitute for bone tissues. Metallic implants are frequently used in orthopedic surgery as joint prosthesis (hip, knee and elbow fracture fixation devices (plates, screws, external fixators and devices for the fixation of the spine. In principle, fixators are devided into external and internal ones, depending on the place of installation (outside or inside the body. The most common types of medical fixators are pins, rods and plates. This paper presents some of the most common materials used for the production of fixators, their processing and possibilties of use in medicine for various purposes. Types of fixators and materials used for their production Nowadays, biocompatible materials are usually used for the production of fixators and implants. These materials show good

  2. Posterior atlantoaxial transpedicle screw fixation for traumatic atlatoaxial instability

    Directory of Open Access Journals (Sweden)

    Zheng-lei WANG

    2015-10-01

    Full Text Available Objective To explore the clinical efficacy of posterior atlantoaxial pedicle screw fixation for traumatic atlantoaxial instability. Methods From September 2009 to March 2013, 17 patients with atlantoaxial instability received posterior atlantoaxial pedicle screw fixation. There were 12 males and 5 females, with a mean age of 42 years old (ranged from 19 to 63 years old. Transpedicle screw fixation was employed in 8 patients with atlantoaxial fracture and dislocation, in 2 with traumatic disruption of transverse atlantal ligament, and in 7 with odontoid fracture. The Japanese Orthopaedic Association (JOA score before operation was from 5 to 14, with a mean of 11.2. Preoperative CT, MRI and radiographs, as well as intraoperative screw placement and bone graft were administered in all the patients. Results In all the patients, complete reduction was achieved without injury to the vertebral artery, spinal cord or never root, and they started to be ambulatory on the first day after the operation. The patients were followed up for 6-36 months (mean 21 months, and clinical symptoms were seen to be improved significantly. Imaging reexamination 6 months after the surgery showed satisfactory healing of implanted bone and position of all the screws without loosening of the implant. The mean JOA scores was 15.5(11.0-17.0 twelve months after the operation. Conclusion Atlantoaxial pedicle screw fixation for traumatic atlantoaxial instability is safe and reliable with a favorable clinical result. DOI: 10.11855/j.issn.0577-7402.2015.09.14

  3. Biodegradation of Polypropylene Nonwovens

    Science.gov (United States)

    Keene, Brandi Nechelle

    The primary aim of the current research is to document the biodegradation of polypropylene nonwovens and filament under composting environments. To accelerate the biodegradat ion, pre-treatments and additives were incorporated into polypropylene filaments and nonwovens. The initial phase (Chapter 2) of the project studied the biodegradation of untreated polypropylene with/without pro-oxidants in two types of composting systems. Normal composting, which involved incubation of samples in food waste, had little effect on the mechanical properties of additive-free spunbond nonwovens in to comparison prooxidant containing spunbond nonwovens which were affected significantly. Modified composting which includes the burial of samples with food and compressed air, the polypropylene spunbond nonwovens with/without pro-oxidants displayed an extreme loss in mechanical properties and cracking on the surface cracking. Because the untreated spunbond nonwovens did not completely decompose, the next phase of the project examined the pre-treatment of gamma-irradiation or thermal aging prior to composting. After exposure to gamma-irradiation and thermal aging, polypropylene is subjected to oxidative degradation in the presence of air and during storage after irradiat ion. Similar to photo-oxidation, the mechanism of gamma radiation and thermal oxidative degradation is fundamentally free radical in nature. In Chapter 3, the compostability of thermal aged spunbond polypropylene nonwovens with/without pro-oxidant additives. The FTIR spectrum confirmed oxidat ion of the polypropylene nonwovens with/without additives. Cracking on both the pro-oxidant and control spunbond nonwovens was showed by SEM imaging. Spunbond polypropylene nonwovens with/without pro-oxidants were also preirradiated by gamma rays followed by composting. Nonwovens with/without pro-oxidants were severely degraded by gamma-irradiation after up to 20 kGy exposure as explained in Chapter 4. Furthermore (Chapter 5), gamma

  4. Stabilisation of a mandibular fracture in a cow by means of a pinless external fixator

    International Nuclear Information System (INIS)

    A four months pregnant, four-year-old Brown Swiss cow with mandibular fractures of the right horizontal ramus and the symphysis was treated surgically with a new pinless external fixator. Healing was complicated by the sequestration of bone at the fracture site. After the sequestrum had been removed a radiographic examination revealed that the fracture had healed completely

  5. QWIX螺钉置入内固定修复髌骨骨折:骨折断端的持续动静态加压作用%QWIX screw fixation in repair of patellar fractures:continuous dynamic and static pressure in the broken ends of the bones

    Institute of Scientific and Technical Information of China (English)

    刘杰; 高仕长; 梁安霖

    2014-01-01

    remaining patients. In accordance with Bostman score, there were excellent in 27 cases, good in 3 cases, and poor in 0 case, with an excellent and good rate of 100%at 1 year fol owing surgery. Results data suggested that QWIX screws combined with Kirschner wire and wire fixation in repair of patel ar fracture have some advantages such as continuous dynamic and static pressure at the broken ends of the bones, early flexion and extension exercises, and reducing the fixation-related complications. It is an effective method to repair patel ar fracture.

  6. Novel anterior cruciate ligament graft fixation device reduces slippage

    Directory of Open Access Journals (Sweden)

    Lopez MJ

    2013-05-01

    Full Text Available Mandi J Lopez,1 Allen Borne,2 W Todd Monroe,3 Prakash Bommala,1 Laura Kelly,1 Nan Zhang11Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, 2Louisiana State University, New Orleans Health Sciences Center, School of Medicine, New Orleans, 3Department of Biological and Agricultural Engineering, Agricultural Center, Louisiana State University, Baton Rouge, LA, USAAbstract: Clinically significant laxity occurs in 10%–30% of knees after anterior cruciate ligament reconstruction. Graft slippage and tension loss at the hamstring graft tibial fixation site during and after reconstruction surgery contribute to postoperative joint laxity and are detrimental to long-term knee stability and graft properties. Limiting graft slippage will reduce associated complications. We sought to compare the in vitro mechanical properties and in vivo joint stabilization, postoperative limb use, and graft incorporation of the novel GraftGrab™ (GG device designed to reduce hamstring graft tibial fixation slippage with the commercially available bioabsorbable Bio-Post™ and spiked washer (BP. Mechanical testing was performed on canine tibia-hamstring graft constructs to quantify initial fixation properties. In vivo joint stabilization, postoperative limb use and graft incorporation of hamstring graft reconstructions were determined in a canine model. Outcomes included tibial translation and ground reaction forces preoperatively and 4 and 8 weeks postoperatively, three-dimensional graft and bone tunnel dimensions at the latter two time points, and graft-bone microstructure, as well as mechanical properties 8 weeks after implantation. Immediately after fixation, all grafts slipped from the BP constructs versus about 30% of GG constructs. In vivo limb use remained low, and tibial translation increased with time in the BP cohort. These results together

  7. 带缝匠肌骨瓣移植联合空心钉内固定治疗青少年股骨颈骨折的临床效果分析%Clinical effect analysis of sartorial-pedicled ilium bone transplantation combined with hollow screw fixation treating femoral neck fracture of youngsters

    Institute of Scientific and Technical Information of China (English)

    郑凌云; 邓秋平; 田华强; 方良韬

    2015-01-01

    目的:分析带缝匠肌骨瓣移植联合空心钉内固定对青少年股骨颈骨折的治疗效果。方法选取本院2012年7月~2014年6月收治的80例青少年股骨颈骨折患者,按随机数字表法分成研究组和对照组,各40例。研究组采用带缝匠肌骨瓣移植术联合空心钉内固定术进行治疗;对照组单纯采用空心螺钉内固定术进行治疗。比较两组手术时间、术中出血量、住院时间、股骨头缺血性坏死发生率、骨折愈合时间、临床疗效及治疗前、后生活质量。结果研究组手术时间长于对照组(P0.05);研究组股骨头缺血性坏死发生率低于对照组(P0.05);研究组治疗后生活质量得分高于对照组(P0.05). The life quality score of research group after treatment was higher than that of control group (P<0.05). Conclusion Sartorial-pedicled ilium bone transplantation combined with hollow screw fixation treating femoral neck fracture of youngsters has the advantages of rapid recovery and good efficacy.

  8. Rapid method for fetal brain fixation.

    OpenAIRE

    Nicholls, J. M.

    1988-01-01

    A quicker alternative to the standard removal and fixation of brain tissue was sought. Whole fetal brains were fixed in situ using a mercuric based fixative. The subarachnoid space was perfused overnight with Heidenhain's Susa fixative. The following day the brains were removed from the cranium in the standard manner. After storage for three days in Susa's fixative the brain was sliced and processed, with excellent preservation of gross and microscopic architecture. The cost is only marginall...

  9. External fixation in contemporary fracture management

    OpenAIRE

    McCoy, G. F.; Orr, J. F.; Templeton, J.

    1987-01-01

    Important advances have been made within the last two decades in the field of fracture management. The development of the AO internal fixation system and the advances in cast bracing techniques are but two of the improvements worthy of mention. It is, however, in the field of external fixation of fractures that the greatest advances have been made. This paper traces the history of external fixation up to the present day and discusses, with examples, the application of external fixation in the...

  10. Biodegradable micromechanical sensors

    DEFF Research Database (Denmark)

    Keller, Stephan Sylvest; Greve, Anders; Schmid, Silvan;

    The development of biopolymers for food packaging, medical engineering or drug delivery is a growing field of research [1]. At the same time, the interest in methods for detailed analysis of biopolymers is increasing. Micromechanical sensors are versatile tools for the characterization of mechani......The development of biopolymers for food packaging, medical engineering or drug delivery is a growing field of research [1]. At the same time, the interest in methods for detailed analysis of biopolymers is increasing. Micromechanical sensors are versatile tools for the characterization...... of biopolymers to microfabrication is challenging, as these polymers are affected by common processes such as photolithography or wet etching. Here, we present two methods for fabrication of biodegradable micromechanical sensors. First, we fabricated bulk biopolymer microcantilevers using nanoimprint lithography...

  11. Bone Cement Augmentation of Pedicle Screw Fixation Combined with Kyphoplasty for Osteoporotic Thoracolumbar Burst Fractures%骨水泥强化椎弓根螺钉固定结合椎体后凸成形术治疗骨质疏松性胸腰段爆裂骨折

    Institute of Scientific and Technical Information of China (English)

    于亮; 蒋伟宇; 赵刘军; 马维虎; 徐荣明

    2014-01-01

    [目的]评估骨水泥强化椎弓根螺钉固定结合椎体后凸成形术(percutaneous kyphoplasty,PKP)治疗骨质疏松性胸腰椎爆裂骨折的临床疗效。[方法]收集本院2011年1月至2012年12月采用骨水泥强化椎弓根螺钉固定结合PKP治疗的31例无神经损伤的骨质疏松性胸腰椎爆裂骨折患者,观测术前、术后1周及术后1年伤椎前后缘压缩率改变、后凸Cobb角、视觉模拟评分(visual analogue scale,VAS)及术后并发症,评估手术效果。[结果]术前椎体前、后缘压缩率分别为(49.5±6.1)%和(16.7±3.2)%,术后1年椎体前后缘压缩率分别为(9.1±1.3)%和(1.2±0.9)%,Cobb角由术前平均(25.7±4.5)°矫正至术后(3.3±2.1)°,平均矫正19.8°,VAS评分由术前平均(7.2±0.5)分降为术后(1.9±0.6)分,各项指标术后与术前比较差异均有统计学意义(P<0.05)。术后随访12~24个月,无1例发生手术并发症。[结论]骨水泥强化椎弓根螺钉固定结合PKP治疗骨质疏松性胸腰椎爆裂骨折,能有效恢复脊柱矢状序列,同时也能较好地维持伤椎的高度和强度,避免术后椎体塌陷,有助于早期康复,减少并发症。%Objective] To assess the efficacy of bone cement augmentation of pedicle screw fixation combined with kyphoplasty for osteoporotic thoracolumbar burst fractures. [Methods] Thirty-one cases of neurological y intact osteoporotic thoracolumbar burst fractures treated by bone cement augmentation of pedicle screw fixation combined with kyphoplasty between January 2011 and December 2012 were included in this study. Then analyze the front and back edges height of the injured vertebra, kyphosis Cobb ’s angle, visual analogue scale(VAS) and complications. [Results] Patients were fol owed up for 12 to 24 months(mean 18.2 months), there was no complication. Al patients recovered satisying, front and back edges of the compression ratio was (49.5±6.1)%and

  12. 强化螺钉治疗老年腰椎管狭窄近中期疗效%The short and midterm clinical effect of pedicle screw fixation with bone cement augmentation in the treatment of senile lumbar spinal stenosis

    Institute of Scientific and Technical Information of China (English)

    瞿岱彪; 黄圣升; 吴华; 刘礼金

    2015-01-01

    目的:评价骨水泥强化椎弓根螺钉内固定治疗伴老年腰椎管狭窄症的近中期临床疗效。方法2012年6月至2014年6月间应用骨水泥强化椎弓根螺钉治疗老年性腰椎管狭窄患者24例,所有患者术前均行骨密度测定诊断为骨质疏松症。采用VAS、JOA下腰痛评分及Oswestry功能障碍指数问卷表(ODI)评分标准评价临床疗效。结果24例患者随访6-24个月,平均(11.50±2.11)个月,不适症状均得到一定改善。 VAS评分术前(7.55±1.30)、术后3个月为(3.65±0.87)、术后6个月为(3.15±0.71)、末次为(2.83±2.04);JOA评分术前为(8.66±7.01)、术后3个月为(14.09±2.07)、术后6个月为(16.88±1.95)、末次随访为(17.33±1.74);ODI评分术前为(0.71±0.31)、术后3个月为(0.44±0.12)、术后6个月为(0.31±0.11)、末次随访为(0.29±0.07)。术后3个月、6个月、末次随访所有评价指标分别与术前对比,差异均有统计学意义(P<0.05)。随访时复查相关影像学资料示只有1例因外伤出现椎弓根螺钉松动,末次随访椎间融合率高达87%。结论对于老年性合并骨质疏松的腰椎管狭窄症患者,应用骨水泥强化椎弓根螺钉技术临床疗效确切,有术后椎间融合率高、发生内固定松动率低、二次手术风险低等优势。%Objective To observe the short and midterm clinical effect of pedicle screw fixation with bone cement augmenta-tion in the treatment of senile lumbar spinal stenosis. Methods From June 2012 to June 2014,24 patients with Lumbar Spinal Stenosis and osteoporosis were treated by posterior decompression,intervertebral fusion with pedicle screw fixation with bone ce-ment augmentation. Osteoporosis was diagnosed by dual-energy X-ray absorptiometry (DEXA) examination in all cases preopera-tively. The clinical results were investigated by measuring VAS and JOA and ODI scoring. Results 24 patients were followed up from 6 to 24 months (average 11.50

  13. Clinical research of posterior limited decompression bone fusion internal fixation in treatment of lumbar degenerative instability%后路有限减压植骨融合内固定治疗腰椎退变性不稳的临床研究

    Institute of Scientific and Technical Information of China (English)

    吴发泳; 尹金铭; 林榕镔; 罗佛长

    2015-01-01

    目的:探讨后路有限减压植骨融合内固定治疗腰椎退变性不稳的临床效果。方法选取本院2010年10月~2014年2月诊治的腰椎退变性不稳患者106例,采用随机数字表法分为两组,各53例。对照组患者采用传统后路开放手术治疗,观察组患者采用后路有限减压植骨融合内固定治疗,比较两组的治疗效果。结果观察组患者的术中出血量、术后引流量明显少于对照组,切口长度明显小于对照组,下床活动时间、术后住院时间明显短于对照组(P<0.05)。治疗后,两组患者的Oswestry功能障碍指数(疼痛、行走、坐立、自理能力、提物、睡眠、总评分)、VAS评分均显著降低,疼痛程度均明显减轻,且观察组治疗后的Oswestry功能障碍指数(疼痛、行走、坐立、自理能力、提物、睡眠、总评分)、VAS评分明显低于对照组,疼痛程度明显轻于对照组(P<0.05);观察组的术后并发症发生率均明显低于对照组(P<0.05)。结论后路有限减压植骨融合内固定是治疗腰椎退变性不稳的有效方法,具有创伤小、疼痛轻、术后恢复快、并发症少、安全性高等优点。%Objective To investigate clinical effect of posterior limited decompression bone fusion internal fixation in treatment of lumbar degenerative instability. Methods 106 patients with lumbar degenerative instability diagnosed and treated in our hospital were selected from October 2010 to February 2014,and they were randomly divided into two groups,and there were 53 patients in each group.Control group was treated with traditional posterior open operation while observation group was treated with posterior limited decompression bone fusion internal fixation as observation group.Ttreatment effect was compared between two groups. Results Intraoperative bleeding volume and postoperative drainage volume in observation group was obviously less than that of control group respectively

  14. Biodegradation of biodiesel fuels

    International Nuclear Information System (INIS)

    Biodiesel fuel test substances Rape Ethyl Ester (REE), Rape Methyl Ester (RME), Neat Rape Oil (NR), Say Methyl Ester (SME), Soy Ethyl Ester (SEE), Neat Soy Oil (NS), and proportionate combinations of RME/diesel and REE/diesel were studied to test the biodegradability of the test substances in an aerobic aquatic environment using the EPA 560/6-82-003 Shake Flask Test Method. A concurrent analysis of Phillips D-2 Reference Diesel was also performed for comparison with a conventional fuel. The highest rates of percent CO2 evolution were seen in the esterified fuels, although no significant difference was noted between them. Ranges of percent CO2 evolution for esterified fuels were from 77% to 91%. The neat rape and neat soy oils exhibited 70% to 78% CO2 evolution. These rates were all significantly higher than those of the Phillips D-2 reference fuel which evolved from 7% to 26% of the organic carbon to CO2. The test substances were examined for BOD5 and COD values as a relative measure of biodegradability. Water Accommodated Fraction (WAF) was experimentally derived and BOD5 and COD analyses were carried out with a diluted concentration at or below the WAF. The results of analysis at WAF were then converted to pure substance values. The pure substance BOD5 and COD values for test substances were then compared to a control substance, Phillips D-2 Reference fuel. No significant difference was noted for COD values between test substances and the control fuel. (p > 0.20). The D-2 control substance was significantly lower than all test substances for BCD, values at p 5 value

  15. Understanding Nitrogen Fixation

    Energy Technology Data Exchange (ETDEWEB)

    Paul J. Chirik

    2012-05-25

    synthesis of ammonia, NH{sub 3}, from its elements, H{sub 2} and N{sub 2}, via the venerable Haber-Bosch process is one of the most significant technological achievements of the past century. Our research program seeks to discover new transition metal reagents and catalysts to disrupt the strong N {triple_bond} N bond in N{sub 2} and create new, fundamental chemical linkages for the construction of molecules with application as fuels, fertilizers and fine chemicals. With DOE support, our group has discovered a mild method for ammonia synthesis in solution as well as new methods for the construction of nitrogen-carbon bonds directly from N{sub 2}. Ideally these achievements will evolve into more efficient nitrogen fixation schemes that circumvent the high energy demands of industrial ammonia synthesis. Industrially, atmospheric nitrogen enters the synthetic cycle by the well-established Haber-Bosch process whereby N{sub 2} is hydrogenated to ammonia at high temperature and pressure. The commercialization of this reaction represents one of the greatest technological achievements of the 20th century as Haber-Bosch ammonia is responsible for supporting approximately 50% of the world's population and serves as the source of half of the nitrogen in the human body. The extreme reaction conditions required for an economical process have significant energy consequences, consuming 1% of the world's energy supply mostly in the form of pollution-intensive coal. Moreover, industrial H{sub 2} synthesis via the water gas shift reaction and the steam reforming of methane is fossil fuel intensive and produces CO{sub 2} as a byproduct. New synthetic methods that promote this thermodynamically favored transformation ({Delta}G{sup o} = -4.1 kcal/mol) under milder conditions or completely obviate it are therefore desirable. Most nitrogen-containing organic molecules are derived from ammonia (and hence rely on the Haber-Bosch and H{sub 2} synthesis processes) and direct synthesis from

  16. UK DRAFFT - A randomised controlled trial of percutaneous fixation with kirschner wires versus volar locking-plate fixation in the treatment of adult patients with a dorsally displaced fracture of the distal radius

    OpenAIRE

    Brown Jaclyn; Edlin Richard P; Rangan Amar; Parsons Nick R; Achten Juul; Costa Matthew L; Lamb Sarah E

    2011-01-01

    Abstract Background Fractures of the distal radius are extremely common injuries in adults. However, the optimal management remains controversial. In general, fractures of the distal radius are treated non-operatively if the bone fragments can be held in anatomical alignment by a plaster cast or orthotic. However, if this is not possible, then operative fixation is required. There are several operative options but the two most common in the UK, are Kirschner-wire fixation (K-wires) and volar ...

  17. Evaluation of hydroxyapatite and beta-tricalcium phosphate mixed with bone marrow aspirate as a bone graft substitute for posterolateral spinal fusion

    OpenAIRE

    Bansal Sanjay; Chauhan Vijendra; Sharma Sansar; Maheshwari Rajesh; Juyal Anil; Raghuvanshi Shailendra

    2009-01-01

    Background: Autologous cancellous bone is the most effective biological graft material. However, harvest of autologous bone is associated with significant morbidity. Since porous hydroxyapatite and beta-tricalcium phosphate are biodegradable materials and can be replaced by bone tissue, but it lacks osteogenic property. We conducted a study to assess their use as a scaffold and combine them with bone marrow aspirate for bone regeneration using its osteogenic property for posterolateral spina...

  18. Minimally Invasive Pedicle Screw Fixation Combined with Vertebroplasty with Calcium Phosphate Bone Cement in the Treatment of Thoracolumbar Burst Fracture%微创椎弓根钉内固定联合磷酸钙骨水泥椎体成形术治疗胸腰椎爆裂性骨折

    Institute of Scientific and Technical Information of China (English)

    顾宇彤; 梁朝革; 张亮; 林红; 周健

    2015-01-01

    目的:评估微创椎弓根钉内固定(微小切口非空心椎弓根钉技术)联合磷酸钙骨水泥经皮穿刺椎体成形术(percutaneous vertebroplasty ,PVP)治疗胸腰椎爆裂性骨折的疗性和安全性。方法:采用微创椎弓根钉内固定联合磷酸钙骨水泥 PVP术治疗23例单节段胸腰椎新鲜爆裂性骨折且无神经症状的患者,伤椎位于 T11~L2,均属A3型骨折。记录手术时间、术中出血量、骨水泥注射量和住院天数。记录术前及术后即刻、1个月、2个月、3个月、6个月、1年、2年的腰背痛评分,计算并比较各时点的椎体高度压缩率、恢复率、椎体后凸角、椎体后凸矫正率。结果:磷酸钙骨水泥平均注射量为4.9(3.8~6.4)mL,平均手术时间92(75~120) min ,平均出血量52(40~75) mL ,平均住院5.6(4~7) d ,术后平均随访26(24~29)个月。VAS评分由术前的(8.8±1.2)分下降至术后即刻的(1.8±0.6)分及术后2年的(0.4±0.5)分,差异均有显著统计学意义(P<0.001)。高度压缩率由术前的(50.4±7.2)%显著下降至术后即刻的(6.2±1.5)%及术后2年的(6.9±1.4)%,差异均有显著统计学意义(P<0.001)。后凸角由术前的(22.6±1.8)°下降至术后即刻的(3.2±1.7)°及术后2年的(5.1±1.5)°,差异均有显著统计学意义( P<0.001)。随访过程中术后高度恢复率、后凸矫正率无明显减小;未出现螺钉松动、断钉或断棒。结论:微创椎弓根钉内固定联合磷酸钙骨水泥PV P术是治疗胸腰椎爆裂性骨折的安全、有效的方法。%Objective:To evaluate the efficacy and safety of minimally invasive pedicle screw fixation combined with percutaneous vertebroplasty(PVP) with calcium phosphate bone cement in the treatment of acute thoracolumbar burst fracture . Methods:Twenty‐three patients

  19. FOSSIL FUEL BIODEGRADATION: LABORATORY STUDIES

    Science.gov (United States)

    Natural processes of biodegradation, that return carbon from its various organic forms to the inorganic state, are increasingly screened for bioremediation applications. ariety of microbial systems capable of degrading synthetic organic chemicals, from pesticides to polychlorinat...

  20. Scaphoid Fracture Fixation with an Acutrak(®) Screw.

    Science.gov (United States)

    Loving, Vilert A; Richardson, Michael L

    2006-01-01

    We report a case of fixation of a scaphoid fracture using an Acutrak(®) screw. This screw is cannulated and headless, which allows it to be implanted below the surface of the bone. It uses the same concept of variable thread pitch as the Herbert screw, but unlike the Herbert screw, is fully threaded, with continuously varying pitch along its length. This variable pitch creates constant compression across a fracture as the screw is advanced, and gives the screw its unique appearance. This feature may improve internal holding power, as well as allow a fracture or osteotomy site to lie anywhere along the length of the screw. PMID:27298683

  1. New method for fixation point of tibialis posterior tendon transfer

    OpenAIRE

    Yeganeh, Ali; Motaghi, Arash; Shahhoseini, Gholamreza; Farahini, Hosein

    2013-01-01

    Background The transfer of the tibialis posterior tendon to the dorsum of foot can restore the function of theparalyzed dorsiflexor muscles of the foot and ankle. In order to reduce the wound complication in the insertionsite of tendon to bone by a plantar knop we used a new method of fixation by an absorbable screw inserted dorsally. Methods we performed this operation on 15 patients in a 3 years period. All patients had drop foot deformitydue to irreversible lesions of the peroneal nerve. T...

  2. Anaerobic biodegradability of kitchen waste

    OpenAIRE

    Neves, L.; Oliveira, Rosário; M. Mota; Alves, M.M.

    2002-01-01

    Biodegradability of synthetic and real kitchen wastes was assessed in batch assays, under different solid contents between 1,8 and 24% and waste/inoculum ratios between 0,2 and 29 VSwaste/Vsseed sludge. Methanization rate and cumulative methane production from synthetic wastes simulated with different blends of protein, carbohydrates, fat and cellulose were compared. Although the excess of protein, carbohydrates and cellulose enhanced the biodegradability by 16 to 48%, the excess of fat re...

  3. Whole Animal Perfusion Fixation for Rodents

    OpenAIRE

    Gage, Gregory J.; Kipke, Daryl R.; Shain, William

    2012-01-01

    The goal of fixation is to rapidly and uniformly preserve tissue in a life-like state. While placing tissue directly in fixative works well for small pieces of tissue, larger specimens like the intact brain pose a problem for immersion fixation because the fixative does not reach all regions of the tissue at the same rate 5,7. Often, changes in response to hypoxia begin before the tissue can be preserved 12. The advantage of directly perfusing fixative through the circulatory system is that t...

  4. Clinical effects of posterior decompression and fixation with trans-pedicle bone graft on 24 cases of fresh upper and middle thoracic spine burst fracture%后路减压经椎弓根植骨配合脊柱后路内固定术治疗中上段胸椎新鲜爆裂骨折24例疗效观察

    Institute of Scientific and Technical Information of China (English)

    宫岩虎; 金正; 张伟

    2014-01-01

    目的:观察后路减压经椎弓根植骨配合脊柱后路内固定术治疗中上段胸椎新鲜爆裂骨折的疗效。方法对2007年1月至2012年12月收治的24例中上段胸椎新鲜爆裂骨折患者的临床资料进行回顾性研究。其中,男20例,女4例;年龄18~54岁,平均32.4岁;骨折累及节段:T21例,T32例,T44例,T53例,T66例,T78例,T83例,T92例,T102例;均合并脊髓损伤,神经损伤按Frankel分级:A级6例,B级5例,C级7例,D级6例。均行脊柱后路减压内固定、经椎弓根植骨术。结果所有患者术后获6~48个月(平均13个月)随访。18例患者神经功能有1~2级的改善,6例A级患者无改善。所有患者植骨融合良好,均无钢板、螺钉松动或断裂发生。对24例患者的cobb角、椎体前、后缘高度、椎管狭窄率进行评价,术后即刻、术后1年与术前比较均有改善,差异有统计学意义(P<0.05),而术后即刻与术后1年比较差异无统计学意义(P>0.05)。结论应用后路减压经椎弓根植骨配合脊柱后路内固定术治疗中上段胸椎新鲜爆裂骨折,具有减压彻底、术后脊柱稳定性好和植骨融合率高等优点。%Objective To explore the clinical effects of posterior decompression and fixation with transvertebral pedicle bone graft in the treatment of fresh upper and middle thoracic spine burst fracture .Methods A retrospective study was made on 24 cases of fresh upper and middle thoracic spine burst fracture hospitalized for treatment from January 2007 to December 2012, including 20 male and 4 female patients, with an age range between 18 and 54, averaging 32.4 years.Bone fracture were involved in the following seg-ments:T2 ( 1 case ), T3 ( 2 cases), T4 ( 4 cases), T5 ( 3 cases), T6 ( 6 cases), T7 ( 8 cases), T8 (3 cases), T9 ( 2 cases), T10 (2 cases), with all the cases complicated with spinal cord injury .In accordance with the Frankel

  5. Allogeneic bone grafting strengthens the internal fixation of proximal humeral fractures in high-risk groups%同种异体骨移植强化高危人群肱骨近端骨折内固定的疗效观察

    Institute of Scientific and Technical Information of China (English)

    苏志辉; 鲁厚根; 刘军; 邹立学; 胡伟

    2016-01-01

    BACKGROUND:Numerous studies have focused on the clinical efficacy of alogeneic bone graft and humeral head replacement for the treatment of proximal humeral fractures, but their comparative studies are rarely reported. OBJECTIVE:To investigate the effect of alogeneic bone grafting in the treatment of proximal humeral fractures in the high risk group. METHODS:Clinical data of 120 cases of proximal humeral fractures aged≥ 60 years were retrospectively analyzed. Sixty of the 120 cases underwent alogeneic bone grafting combined with locking plate fixation as experimental group, and the other 60 cases were subjected to semi-shoulder joint replacement as control group. Al patients were folowed up for 8-24 months. Fracture healing, colodiaphyseal angle, humeral head height and shoulder joint function were observed and measured. RESULTS AND CONCLUSION:During the postoperative 8-24 months, al the fractures were healed by first intention, and there were no rejection reactions, large/smal nodules, humeral head displacement, necrosis, and screw loosening. Loss of the humeral head height at the last folow-up and the active flexion angle of the shoulder at postoperative 12 weeks were significantly higher in the experimental group than the control group (P < 0.05). Scores on forearm, shoulder and hand dysfunction were significantly lower in the experimental group than the control group (P < 0.05). However, no significant difference was observed in the colodiaphyseal angle and SF-36 scores between the two groups. These finding indicate that alogeneic bone grafting can strength the internal fixation of proximal humeral fractures in the high-risk group, and improve patient’s upper limb function.%背景:大量研究对同种异体骨移植和人工肱骨头置换治疗肱骨近端骨折的临床效果进行了评价,但关于二者的对比性研究报道却非常有限。目的:分析同种异体骨移植强化高危人群肱骨近端骨折内固定的效

  6. Miniplate fixation for the repair of segmental mandibular defects filled with autogenous bone in cats Uso de miniplacas na fixação de mandíbulas de gatos com defeitos segmentares preenchidos com osso autógeno

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    Adelina Maria da Silva

    2011-06-01

    Full Text Available PURPOSE: To evaluate the use of maxillofacial miniplate 1.5 in the repair of segmental mandibular defects filled with autogenous bone in cats. METHODS: Twelve adult cats were divided into two groups. A segmental defect of 4mm was created in one of the hemimandibles and filled with autogenous iliac crest bone graft. The operated hemimandible was fixed with a 1.5mm titanium miniplate. In group 1 (n=6, the defect was performed in the body of the mandible, behind the 1st molar. In group 2 (n=6, the defect was performed between the 4nd premolar and 1st molar, with extraction of the 1st molar. Oral alimentation was reinitiated 24 hours after surgery. Cats were euthanized at 20 weeks postoperative. RESULTS: Incorporation of the graft was suggested by the radiographs taken 20 weeks after surgery. Macroscopic examination confirmed alignment and bone union of operated hemimandibles. Histological examination showed formation of woven bone in rostral and caudal mandible/graft interfaces. The percentage of bone tissue at these areas was measured by the histometry. There was no statistically significant difference between the values of group 1(64.48 ± 4.51 and group 2 (71.69 ± 14.47 (Mann-Whitney's test p= 0.294. CONCLUSION: The use of miniplate 1.5 for the fixation of mandibular defects filled with autogenous bone in cats provided the main goals in the treatment of mandibular fractures: bone union, normal dental occlusion and immediate return to oral alimentation.OBJETIVO: Avaliar o uso de miniplacas na fixação de mandíbulas de gatos com defeitos segmentares preenchidos com osso autógeno. MÉTODOS: Foram utilizados 12 gatos adultos divididos em dois grupos de seis animais cada. Em uma das hemimandíbulas foi criado um defeito segmentar de 4mm, preenchido com enxerto autógeno do osso ilíaco. A hemimandíbula operada foi fixada com uma miniplaca 1.5 de titânio. No grupo 1, o defeito foi realizado caudalmente ao 1º molar e no grupo 2, entre o 4º pr

  7. Cement embolism into the venous system after pedicle screw fixation: case report, literature review, and prevention tips

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    Ghassan Kerry

    2013-09-01

    Full Text Available The strength of pedicle screws attachment to the vertebrae is an important factor affecting their motion resistance and long term performance. Low bone quality, e.g. in osteopenic patients, keeps the screw bone interface at risk for subsidence and dislocation. In such cases, bone cement could be used to augment pedicle screw fixation. But its use is not free of risk. Therefore, clinicians, especially spine surgeons, radiologists, and internists should become increasingly aware of cement migration and embolism as possible complications. Here, we present an instructive case of cement embolism into the venous system after augmented screw fixation with fortunately asymptomatic clinical course. In addition we discuss pathophysiology and prevention methods as well as therapeutic management of this potentially life-threatening complication in a comprehensive review of the literature. However, only a few case reports of cement embolism into the venous system were published after augmented screw fixation.

  8. Bone Grafts

    Science.gov (United States)

    ... repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some types of fractures or cancers. Once your body accepts the bone ...

  9. Experimental and Numerical Modeling of Screws Used for Rigid Internal Fixation of Mandibular Fractures

    Directory of Open Access Journals (Sweden)

    Bret Baack

    2008-05-01

    Full Text Available Experimental and numerical methods are used to explore the stresses generated around bone screws used in rigid internal fixation of mandibular fractures. These results are intended to aid in decisions concerning both the design and the use of these bone screws. A finite element (FE model of a human mandible is created with a fixated fracture in the parasymphyseal region. The mandibular model is anatomically loaded, and the forces exerted by the fixation plate onto the simplified screws are obtained and transferred to another finite element submodel of a screw implant embedded in a trilaminate block with material properties of cortical and cancellous bone. The stress in the bone surrounding the screw implant is obtained and compared for different screw configurations. The submodel analyses are further compared to and validated with simple axial experimental and numerical screw pull-out models. Results of the screw FE analysis (FEA submodel show that a unicortical screw of 2.6 mm major diameter and 1.0 mm pitch will cause less bone damage than a bicortical screw of 2.3 mm major diameter and 1.0 mm pitch. The results of this study suggest that bicortical drilling can be avoided by using screws of a larger major diameter.

  10. Reconstructive procedures on lower extremities using Mitković external fixation system

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    Abdala K.

    2005-01-01

    Full Text Available The results of limb lengthening, correction of limb deformities and solving of bone loss, by the use of Mitković external fixation system and minimally invasive technique on the series of 96 operations in 89 patients are shown. Only lower extremities were included in this series. The advantages of this external fixation system in comparison to other systems are pointed out. The main advantages are the optimal biomechanical conditions including unilateral but 3-dimensional frame, which provides conditions very similar to natural biomechanical features of the human long bones, simplicity of application and low cost. The received result was excellent or very good in 98.4%. Maximal limb lengthening was 18 cm (at the same time in the femur and the tibia. Angular deformity correction is extremely simplified with minimized possibility of complications. The frame for bone transport is very simple. It can be concluded that presented methods are suitable for routine use.

  11. Treatment of neglected elbow dislocations with the help of hinged external fixator: Report of two cases

    Directory of Open Access Journals (Sweden)

    Özgür Karakoyun

    2014-06-01

    Full Text Available Elbow dislocations are cases that have to be treated in emergency conditions. Neglected elbow dislocations are seen very rarely and the treatment of such cases are more complicated than acute cases. We present two cases of neglected elbow dislocations treated with open reduction and hinged external fixators. Case 1: 23 year old female patient had a neglected posterior dislocation of left elbow with ipsilateral humeral shaft fracture caused by car accident. The patient was treated after 3 months of initial trauma. We have performed open reduction for the joint. After that we fixed the joint whit a hinged external fixator. The humeral shaft fracture was also fixed with the components of the external fixator. Case 2: 33 year male patient had a large bone and soft tissue defect around the left elbow accompanying with neglected medial elbow dislocation. He presented to our clinic with a delay of 2 months. The patient was treated with open reduction and hinged external fixator after reconstruction of bone defect of distal humerus. Conclusion: The treatment of neglected cases is quite challenging. Open reduction and external fixation has satisfactory results in treatment of late cases of elbow dislocation with the possibility of early rehabilitation. This method can be considered as an option for such cases. J Clin Exp Invest 2014; 5 (2: 443-446

  12. Progress of biodegradable metals

    Directory of Open Access Journals (Sweden)

    Huafang Li

    2014-10-01

    Full Text Available Biodegradable metals (BMs are metals and alloys expected to corrode gradually in vivo, with an appropriate host response elicited by released corrosion products, then dissolve completely upon fulfilling the mission to assist with tissue healing with no implant residues. In the present review article, three classes of BMs have been systematically reviewed, including Mg-based, Fe-based and Zn-based BMs. Among the three BM systems, Mg-based BMs, which now have several systems reported the successful of clinical trial results, are considered the vanguards and main force. Fe-based BMs, with pure iron and Fe–Mn based alloys as the most promising, are still on the animal test stage. Zn-based BMs, supposed to have the degradation rate between the fast Mg-based BMs and the slow Fe-based BMs, are a rising star with only several reports and need much further research. The future research and development direction for the BMs are proposed, based on the clinical requirements on controllable degradation rate, prolonged mechanical stability and excellent biocompatibility, by optimization of alloy composition design, regulation on microstructure and mechanical properties, and following surface modification.

  13. Biodegradation of polyethoxylated nonylphenols.

    Science.gov (United States)

    Ruiz, Yassellis; Medina, Luis; Borusiak, Margarita; Ramos, Nairalith; Pinto, Gilberto; Valbuena, Oscar

    2013-01-01

    Polyethoxylated nonylphenols, with different ethoxylation degrees (NPEO x ), are incorporated into many commercial and industrial products such as detergents, domestic disinfectants, emulsifiers, cosmetics, and pesticides. However, the toxic effects exerted by their degradation products, which are persistent in natural environments, have been demonstrated in several animal and invertebrate aquatic species. Therefore, it seems appropriate to look for indigenous bacteria capable of degrading native NPEO x and its derivatives. In this paper, the isolation of five bacterial strains, capable of using NPEO 15 , as unique carbon source, is described. The most efficient NPEO 15 degrader bacterial strains were identified as Pseudomonas fluorescens (strain Yas2) and Klebsiella pneumoniae (strain Yas1). Maximal growth rates were reached at pH 8, 27°C in a 5% NPEO 15 medium. The NPEO 15 degradation extension, followed by viscometry assays, reached 65% after 54.5 h and 134 h incubation times, while the COD values decreased by 95% and 85% after 24 h for the Yas1 and Yas2 systems, respectively. The BOD was reduced by 99% and 99.9% levels in 24 h and 48 h incubations. The viscosity data indicated that the NPEO 15 biodegradation by Yas2 follows first-order kinetics. Kinetic rate constant (k) and half life time (τ) for this biotransformation were estimated to be 0.0072 h(-1) and 96.3 h, respectively. PMID:23936727

  14. Progress of biodegradable metals

    Institute of Scientific and Technical Information of China (English)

    Huafang Li; Yufeng Zheng; Ling Qin

    2014-01-01

    Biodegradable metals (BMs) are metals and alloys expected to corrode gradually in vivo, with an appropriate host response elicited by released corrosion products, then dissolve completely upon fulfilling the mission to assist with tissue healing with no implant residues. In the present review article, three classes of BMs have been systematically reviewed, including Mg-based, Fe-based and Zn-based BMs. Among the three BM systems, Mg-based BMs, which now have several systems reported the successful of clinical trial results, are considered the vanguards and main force. Fe-based BMs, with pure iron and Fe–Mn based alloys as the most promising, are still on the animal test stage. Zn-based BMs, supposed to have the degradation rate between the fast Mg-based BMs and the slow Fe-based BMs, are a rising star with only several reports and need much further research. The future research and development direction for the BMs are proposed, based on the clinical requirements on controllable degradation rate, prolonged mechanical stability and excellent biocompat-ibility, by optimization of alloy composition design, regulation on microstructure and mechanical properties, and following surface modification.

  15. PERCUTANEOUS BIPLANAR EXTERNAL FIXATOR METHOD FOR TREATMENT OF CALCONEAL FRACTURES

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    Jagadeesh Kumar

    2015-07-01

    Full Text Available Calcaneal fracture, the most common tarsal bone fracture, occurs predominantly in manual labors and subsequently has got considerable socioeconomic implications. Treatment modality which can offer early weight bearing and early return to work is therefore needed for those patient s. We have used a biplanar percutaneous external fixator for treating calcaneal fractures per operative visualization of the fractures. We have treated 20 calcaneal fractures in 18 patients, 12 intra articular and five extra articular, with our percutaneou s external fixator system with under image intensifier and achieving the fracture reduction. Functional outcome was measured using the American Orthopaedic Foot and ankle society Hind foot score. All fractures united with a mean of 55 days. Partial weight bearing was possible in a mean of 1.8 days and full bearing was possible in a mean of 11.6 days. All the patients were returned to their original work within six weeks. Minor infectious complications occurred in 17.6 percent of cases. The average AOFAS sco re at six months follow up was 83.8. We conclude that our percutaneous external fixator technique for fracture calcaneum is an effective alternative to the currently available – surgical and conservative treatment modalities especially in lower socio econo mic labor population who need to return to their job as early as possible. Level of Evidence – IV Case series

  16. Posteromedial approach of gastrocnemius for reduction and internal fixation of avulsed tibial attachment of posterior cruciate ligament

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-li; XU Hu; LI Ming-quan

    2006-01-01

    Objective:To introduce a posteromedial approach through the medial border of the medial head of gastrocnemius for reduction and reattachment of bony avulsion of the posterior cruciate ligament (PCL) from the tibia.Methods: Eleven patients with avulsed tibial attachment of the PCL underwent an operative reduction and internal fixation through the posteromedial approach of the gastrocnemius in our department from February 1998 to March 2000. The skin incision was reversed L-shaped along the medial border of the medial head of the gastrocnemius and the posterior capsule was exposed by dissecting the medial border and lateral retraction, avoiding the damage of the popliteal neurovascular structures. After that, the posterior capsule was vertically dissected a little medially to the posterior intercondylar sulcus and just on the posterior medial tibial eminence positioned by finger palpation. Then the PCL and its tibial attachment were easily accessible. In the delayed cases, PCL peripheral releasing was necessary to overcome the ligament retraction and to refresh the fracture bed for optimal reduction and bony healing. At last, one or two biodegradable screws were used to fix the avulsed bone segment and 30° flexion knee plaster cast immobilization was regularly applied after the wound was closed. The evaluation included X-ray, posterior sag sign and posterior drawer test compared with the contralateral side. The functional assessment of the low limbs was not available because of concomitant injuries.Results: The posteromedial approach of the gastrocnemius used in repair of tibial attachment avulsed injury of the PCL could provide benefit of clear anatomical exposure, few blood loss (20 ml on average), no need for detachment or reattachment of any structure. The patients were followed up for 11 months on an average (ranging from 6 months to 2 years ). It demonstrated that bony healing was achieved within 4-6 weeks in cases of fresh injury and 7-9 weeks in cases of

  17. REVERSE ENGINEERING OF THE MITKOVIC TYPE INTERNAL FIXATOR FOR LATERAL TIBIAL PLATEAU

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    Nikola Vitković

    2015-12-01

    Full Text Available In orthopaedic surgery it is very important to use proper fixation techniques in the treatment of various medical conditions, i.e. bone fractures or other traumas. If an internal fixation method, such as plating, is required, it is possible to use Dynamic Compression Plates (DCP or Locking Compression Plates (LCP and their variants. For DCP implants it is important to match the patient's bone shape with the most possible accuracy, so that the most frequent implant bending is applied in the surgery. For LCP implants it is not so important to match the patient’s bone shape, but additional locking screw holes are required. To improve the geometrical accuracy and anatomical correctness of the shape of DCP and to improve the LCP geometric definition, new geometrical modelling methods for the Mitkovic type internal fixator for Lateral Tibia Plateau are developed and presented in this research. The presented results are quite promising; it can be concluded that these methods can be applied to the creation of geometrical models of internal fixator customized for the given patient or optimized for a group of patients with required geometrical accuracy and morphological correctness.

  18. Use of a hybrid external skeletal fixator for repair of a periarticular tibial fracture in a Patagonian cavy.

    Science.gov (United States)

    Joyner, Priscilla H; Rochat, Mark C; Hoover, John P

    2004-04-15

    An 8-week-old female Patagonian cavy was examined because of acute right hind limb lameness; radiography revealed a moderately displaced, comminuted fracture of the proximal third of the tibia. The fracture was stabilized with a hybrid external skeletal fixator. Two Kirschner wires were placed in the main proximal fragment, parallel to the tibial plateau and at right angles to each other. These wires were connected to a partial circular external fixator ring. Three half pins were placed in the distal fragment, and a straight connecting rod positioned on the medial side of the limb was connected to these pins and the fixator ring. A second connecting rod was positioned on the craniomedial side of the limb and was connected to the fixator ring and a fourth half pin in the distal fragment. The fracture healed without complications, and the fixator was removed 3 weeks after surgery. Hybrid external skeletal fixators combine the benefits of circular and linear external skeletal fixation methods, enabling rigid fixation of periarticular long bone fractures without adversely affecting mobility of the adjacent joint. PMID:15112778

  19. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

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    Wegner Alexander

    2012-06-01

    Full Text Available Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operative positions of the hip rotation center in 25 and 68 patients who underwent artificial hip replacements in our department in 2007 using cemented or cementless cup fixation, respectively, with digital radiographic image analysis. Results The mean horizontal and vertical distances between the rotation center and the acetabular teardrop were compared in radiographic images taken pre- and post-operatively. The mean horizontal difference was −2.63 mm (range: -11.00 mm to 10.46 mm, standard deviation 4.23 mm for patients who underwent cementless fixation, and −2.84 mm (range: -10.87 to 5.30 mm, standard deviation 4.59 mm for patients who underwent cemented fixation. The mean vertical difference was 0.60 mm (range: -20.15 mm to 10.00 mm, standard deviation 3.93 mm and 0.41 mm (range: -9.26 mm to 6.54 mm, standard deviation 3.58 mm for the cementless and cemented fixation groups, respectively. The two fixation techniques had no significant difference on the position of the hip rotation center in the 93 patients in this study. Conclusions The hip rotation center was similarly restored using either the cemented or cementless fixation techniques in this patient cohort, indicating that the fixation technique itself does not interfere with the position of the center of rotation. To completely answer this question further studies with more patients are needed.

  20. Ossiculoplasty with a cartilage-connecting hydroxyapatite prosthesis for tympanosclerotic stapes fixation.

    Science.gov (United States)

    Kawano, Hirokazu; Matsuda, Keiji; Nakanishi, Haruka; Toyama, Katsuhiro; Nagai, Noriaki; Tono, Tetsuya

    2010-06-01

    Many cases of tympanosclerotic stapes fixation are accompanied by fixation or erosion of malleus and/or incus. This status of the ossicular chain is one of the reasons that ossiculoplasty for tympanosclerotic stapes fixation is more difficult than that for otosclerosis. We conducted a retrospective review of seven patients who were operated on for tympanosclerotic stapes fixation between 2002 and 2006. All of the patients had abnormal conditions of the malleus and/or incus and underwent stapedectomy and total ossiculoplasty with hydroxyapatite prosthesis (Apaceram T-7 type), which has a planar-like head portion that contacts a piece of cartilage. Postoperative hearing results were assessed in all seven patients after at least 1 year. The postoperative air-bone gap (ABG) was closed within 10 dB in two of seven patients, and was less than 20 dB in six of seven patients. The mean postoperative ABG was closed within 10 dB at 1 and 2 kHz and less than 20 dB at low frequencies (0.25 and 0.5 Hz). There was almost no hearing improvement at high frequencies (4 and 8 kHz). There were no patients with postoperative sensorineural hearing loss. The present study shows that stapedectomy and total ossiculoplasty with cartilage-connecting hydroxyapatite prosthesis is effective and safe for stapes fixation accompanied by fixation or erosion of the malleus and/or incus. PMID:19902232

  1. The effects of fixation of the ulna to the radius in young foals

    International Nuclear Information System (INIS)

    The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixation and was accompanied by degenerative joint disease and lameness in foals undergoing fixation at 1 and 5 months of age. Removal of the fixation appliances 16 weeks after implantation in three foals from each of groups I and II failed to reverse the degree of ulnar dysplasia. Although foals undergoing fixation at 7 months of age (group III) were not lame, radiographic evidence of subluxation and subtle degenerative changes in the articular cartilage of the treated elbow did develop. Recommendations for avoidance of radioulnar fixation were developed from these observations

  2. Polymethylmethacrylate-augmented screw fixation for stabilization in metastatic spinal tumors. Technical note.

    Science.gov (United States)

    Jang, Jee Soo; Lee, Sang Ho; Rhee, Chang Hun; Lee, Seung Hoon

    2002-01-01

    Screw fixation augmented with polymethylmethacrylate (PMMA) or some other biocompatible bone cement has been used in patients with osteoporosis requiring spinal fusion. No clinical studies have been conducted on PMMA-augmented screw fixation for stabilization of the vertebral column in patients with metastatic spinal tumors. The purpose of this study was to determine whether screw fixation augmented with PMMA might be suitable in patients treated for multilevel metastatic spinal tumors. Ten patients with metastatic spinal tumors involving multiple vertebral levels underwent stabilization procedures in which PMMA was used to augment screw fixation after decompression of the spinal cord. Within 15 days, partial or complete relief from pain was obtained in all patients postoperatively. Two of four patients in whom neurological deficits caused them to be nonambulatory before surgery were able to ambulate postoperatively. Neither collapse of the injected vertebral bodies nor failure of the screw fixation was observed during the mean follow-up period of 6.7 months. Screw fixation augmented with PMMA may offer stronger stabilization and facilitate the instrumentation across short segments in the treatment of multilevel metastatic spinal tumors. PMID:11795702

  3. Relative motion at the bone-prosthesis interface

    NARCIS (Netherlands)

    Keja, M.; Wevers, H.W.; Siu, D.; Grootenboer, H.J.

    1994-01-01

    Bone ingrowth in porous surfaces of human joint implants is a desired condition for long-term fixation in patients who are physically active (such as in sport or work). It is generally recognized that little actual bone ingrowth occurs. The best clinical results report between 10 and 20% of the tota

  4. Effects of the Biodegradation on Biodegradable Polymer Blends and Polypropylene

    Science.gov (United States)

    Pereira, R. C. T.; Franchetti, S. M. M.; Agnelli, J. A. M.; Mattoso, L. H. C.

    2008-08-01

    The large use of plastics in the world generates a large amount of waste which persists around 200 years in the environment. To minimize this effect is important to search some new polymer materials: the blends of biodegradable polymers with synthetic polymers. It is a large area that needs an intensive research to investigate the blends properties and its behavior face to the different treatments to aim at the biodegradation. The blends used in this work are: some biodegradable polymers such as: poly(hydroxybutyrate) (PHB) and poly(ɛ-polycaprolactone) (PCL) with a synthetic polymer, polypropylene (PP), in lower concentration. These blends were prepared using an internal mixer (Torque Rheometer), and pressed. These films were submitted to fungus biotreatment. The films analyses will be carried out by Fourier Transform Infrared (FTIR), UV-Vis absorption (UV-Vis), Scanning Electronic Microscopy (SEM), DSC and TGA.

  5. Preliminary fabrication of tissue engineered veins containing valves using bone marrow mesenchymal stem cells and biodegradable scaffolds in vitro%骨髓间充质干细胞联合可降解支架体外构建组织工程带瓣静脉

    Institute of Scientific and Technical Information of China (English)

    刘池拽; 殷恒讳; 吕伟明; 曾晨光; 刘畅; 王文见; 全大萍; 项鹏; 王深明

    2014-01-01

    Beagle dogs by density gradient centrifugation and adherence methods. Bone marrow mesenchymal stem cells were cultured in vitro. Fol owing isolation and culture the cells were examined using flow cytometry and identified by direct induction towards the osteogenic and adipogenic lineages. We fabricated biodegradable venous scaffold containing valves using the method of injection molding combined with thermal y induced phase separation. Based on the self-made cast, a three-dimensional biodegradable vein scaffold containing valves was constructed from poly(lactic-co-glycolic acid). Morphological structure was tested. Bone marrow mesenchymal stem cells were used as seed cells to be seeded onto the lumen of the tissue engineered vein scaffold containing valves in vitro and then incubated for 2 weeks. RESULTS AND CONCLUSION:Scanning electron microscopy images showed that the scaffold demonstrated sufficient porosity. Cultured cells expressed mesenchymal cellmarkers, CD44 and CD29, but did not express hematopoietic cellmarkers, CD34 and CD45 at the same time point. Scaffolds were nontoxic to cells and were favorable for the growth and migration of bone marrow mesenchymal stem cells. cells attached on the surface of poly(lactic-co-glycolic acid) scaffolds formed a confluent layer after incubation. The cellular constructs were tested in vitro, and the valve leaflets were functional y capable of opening and closing when stimulated. These results suggested that the tissue engineered vein containing valves have been successful y constructed by using a three-dimensional poly(lactic-co-glycolic acid) scaffold and bone marrow mesenchymal stem cells as seed cells. Tissue engineered vein containing valves is potential y useful for the substitution and regeneration of vein valves.

  6. 椎间打压植骨联合棘突椎板复合体回植内固定治疗退变性腰椎不稳症%LUMBAR INTERBODY FUSION IMPACTED BONE GRAFTS COMBINED WITH REGRAFTING IN SITU WITH SPINOUS PROCESS AND VERTEBRAL PLATE COMPLEX AND PEDICLE SCREW FIXATION FOR LUMBAR DEGENERATIVE INSTABILITY

    Institute of Scientific and Technical Information of China (English)

    张超远; 孟祥翔; 秦晓彬; 付玉娟; 付鹏军

    2012-01-01

    Objective To evaluate the effectiveness of lumbar interbody fusion impacted bone grafts combined with regrafting in situ with spinous process and vertebral plate complex and pedicle screw fixation for lumbar degenerative instability. Methods Between January 1998 and October 2010, 48 patients with lumbar degenerative instability were treated by posterior decompression, lumbar interbody fusion impacted bone grafts combined with regrafting in situ with spinous process and vertebral plate complex and pedicle screw fixation. There were 26 males and 22 females, aged 52-76 years (mean, 62.4 years). The disease duration was 7 months to 25 years (mean, 6.5 years). One segmental instability was located at L3,4 in 1 case, at L4,5 in 10 cases, and at L5, S1 in 11 cases; multi-segmental instability was located at L3,4, L4,5, and L5, S1 in 5 cases, at L2,3 and L3,4 in 2 cases, at L3,4 and L4,5 in 10 cases, and at L4,5 and L5, S1 in 9 cases. Of 48 patients, 32 complicated by lumbar disc herniation, 46 by lumbar spinal stenosis, and 16 by degenerative scoliosis. The clinical results were evaluated by the Japanese Orthopaedic Association (JOA) score, recovery rate, disc height, and lumbar lordosis angles. Results The incisions obtained healing by first intention after operation. No nerve injury, rod or screw breakage, and infection occurred during and after operation. All 48 patients were followed up 1 to 6 years. The fusion time was 12-18 weeks (mean, 16.2 weeks). Vertebra slipping or degenerative scoliosis was corrected, and spinal column series became normal. At preoperation, 6 months after operation, and last follow-up, the disc heights were (5.2 ± 2.3), (11.9 ± 2.0), and (11.6 + 2.1) mm, respectively; the JOA scores were 3.2 + 2.1, 12.8 ± 1.6, and 13.6 + 1.2, respectively; and the lumbar lordosis angles were (-20.5 ± 10.5), (30.5 ± 8.5), and (31.2 + 5.6)°, respectively. The JOA scores, disc heights, and lumbar lordosis angles were significantly improved at 6 months after

  7. WRIST ARTHRODESIS WITH MINIMAL FIXATION PRESERVING THE CARPOMETACARPAL JOINTS

    Science.gov (United States)

    Pardini, Arlindo Gomes; Pádua Gonçalves, Rodolfo Fonseca; Freitas, Afrânio Donato; Chaves, Antonio Barbosa

    2015-01-01

    Objective: Wrist arthrodesis is a surgical procedure that should always be considered in cases of pathological conditions in which anatomical and functional structures are altered. In general, the results are very satisfactory, particularly for pain relief, and in the majority of cases, there is considerable functional improvement. Various techniques have been described, with different methods of internal fixation, most of which include the carpometacarpal joints in the fusion. The objective of this study was to evaluate the results from wrist arthrodesis using a technique that is simpler, more biological, less expensive, and does not involve the carpometacarpal joints. Methods: Fifteen patients with wrist arthrodesis were evaluated (six with sequelae from trauma, four with rheumatoid arthritis, three with Kienbock grade IV, one with Preiser and one with panarthrosis). The technique consisted of using an iliac bone plate and internal fixation with Kirschner wires, avoiding the carpometacarpal joints. Results: The evaluation was based on consolidation time (93% in seven weeks); movements of the fingers and pronosupination; pinch and grasp strength; functional evaluation through the DASH, pain and patient satisfaction questionnaires. In general, the results were similar to those of other, more aggressive techniques, and the non-inclusion of the carpometacarpal joints did not affect the final result. Conclusion: Wrist arthrodesis with fixation using Kirschner wires and an iliac bone plate, preserving the carpometacarpal joints, gives good or excellent results that are not inferior to those of other techniques that have been described. However, it presents major advantages over other methods: it is less aggressive and cheaper, and does not have the inconvenience and complications associated with the use of plates and screws. PMID:27022522

  8. Adhesion of biocompatible and biodegradable micropatterned surfaces

    NARCIS (Netherlands)

    Kaiser, J.S.; Kamperman, M.M.G.; Souza, E.J.; Schick, B.; Arzt, E.

    2011-01-01

    We studied the effects of pillar dimensions and stiffness of biocompatible and biodegradable micropatterned surfaces on adhesion on different compliant substrates. The micropatterned adhesives were based on biocompatible polydimethylsiloxane (PDMS) and biodegradable poly(lactic-co-glycolic) acid (PL

  9. Bioreactor activated graft material for early implant fixation in bone

    DEFF Research Database (Denmark)

    Snoek Henriksen, Susan; Ding, Ming; Overgaard, Søren

    2011-01-01

    from the iliac crest. For both groups, mononuclear cells were isolated, and injected into a perfusion bioreactor (Millenium Biologix AG, Switzerland). Scaffold granules (Ø~900-1500 µm, ~88% porosity) in group 1, consisted of hydroxyapatite (HA, 70%) with β-tricalcium-phosphate (β-TCP, 30%) (Danish...... Technological Institute, Denmark). The granules were coated with poly-lactic acid (PLA) 12%, in order to increase the mechanical strength of the material (Phusis, France). Scaffold granules (Ø~900-1400 µm, 80% porosity) in group 2 consisted of pure HA/β-TCP (FinCeramica, Italy). For both groups, cells were...

  10. Overcoming fixation with repeated memory suppression.

    Science.gov (United States)

    Angello, Genna; Storm, Benjamin C; Smith, Steven M

    2015-01-01

    Fixation (blocks to memories or ideas) can be alleviated not only by encouraging productive work towards a solution, but, as the present experiments show, by reducing counterproductive work. Two experiments examined relief from fixation in a word-fragment completion task. Blockers, orthographically similar negative primes (e.g., ANALOGY), blocked solutions to word fragments (e.g., A_L_ _GY) in both experiments. After priming, but before the fragment completion test, participants repeatedly suppressed half of the blockers using the Think/No-Think paradigm, which results in memory inhibition. Inhibiting blockers did not alleviate fixation in Experiment 1 when conscious recollection of negative primes was not encouraged on the fragment completion test. In Experiment 2, however, when participants were encouraged to remember negative primes at fragment completion, relief from fixation was observed. Repeated suppression may nullify fixation effects, and promote creative thinking, particularly when fixation is caused by conscious recollection of counterproductive information. PMID:24575886

  11. Poly (3-Hydroxyalkanoates: Biodegradable Plastics

    Directory of Open Access Journals (Sweden)

    Surbhi Jain

    2013-03-01

    Full Text Available During the 1920’s, a polyester called poly (3-hydroxybutyrate was discovered in bacterial cells. This compound, otherwise known as PHB, is part of a polyester family called polyhydroxyalkanoates (PHAs. Polyhydroxyalkanoates are used as an energy and carbon sto rage compound within certain bacterial cells. Polyhydroxyalkanoates (PHAs are thermoplastic, biodegradable polyesters synthesized by some bacteria from renewable carbon sources. However, their application is limited by high production cost. Polyhydroxyalkanoates (PHAs have attracted research and commercial interests worldwide because they can be used as biodegradable thermoplastics and also because they can be produced from renewable resources. This review will present an overview on synthesis and degradation of polyhydroxyalkanoates (PHAs, development as biodegradable plastics and its potential production from renewable resources such as palm oil products.

  12. Synthesis and characterization of biomimetic citrate-based biodegradable composites.

    Science.gov (United States)

    Tran, Richard T; Wang, Liang; Zhang, Chang; Huang, Minjun; Tang, Wanjin; Zhang, Chi; Zhang, Zhongmin; Jin, Dadi; Banik, Brittany; Brown, Justin L; Xie, Zhiwei; Bai, Xiaochun; Yang, Jian

    2014-08-01

    Natural bone apatite crystals, which mediate the development and regulate the load-bearing function of bone, have recently been associated with strongly bound citrate molecules. However, such understanding has not been translated into bone biomaterial design and osteoblast cell culture. In this work, we have developed a new class of biodegradable, mechanically strong, and biocompatible citrate-based polymer blends (CBPBs), which offer enhanced hydroxyapatite binding to produce more biomimetic composites (CBPBHAs) for orthopedic applications. CBPBHAs consist of the newly developed osteoconductive citrate-presenting biodegradable polymers, crosslinked urethane-doped polyester and poly (octanediol citrate), which can be composited with up to 65 wt % hydroxyapatite. CBPBHA networks produced materials with a compressive strength of 116.23 ± 5.37 MPa comparable to human cortical bone (100-230 MPa), and increased C2C12 osterix gene and alkaline phosphatase gene expression in vitro. The promising results above prompted an investigation on the role of citrate supplementation in culture medium for osteoblast culture, which showed that exogenous citrate supplemented into media accelerated the in vitro phenotype progression of MG-63 osteoblasts. After 6 weeks of implantation in a rabbit lateral femoral condyle defect model, CBPBHA composites elicited minimal fibrous tissue encapsulation and were well integrated with the surrounding bone tissues. The development of citrate-presenting CBPBHA biomaterials and preliminary studies revealing the effects of free exogenous citrate on osteoblast culture shows the potential of citrate biomaterials to bridge the gap in orthopedic biomaterial design and osteoblast cell culture in that the role of citrate molecules has previously been overlooked. PMID:23996976

  13. Outcome comparison of Lisfranc injuries treated through dorsal plate fixation versus screw fixation

    OpenAIRE

    Hu, Sun-jun; Chang, Shi-Min; Li, Xiao-Hua; Yu, Guang-rong

    2014-01-01

    OBJECTIVE: The objective of this prospective study was to test whether the treatment of Lisfranc injuries with open reduction and dorsal plate fixation would have the same or better functional outcomes as treatment with standard trans-articular screw fixation. METHODS: Sixty patients with primarily isolated Lisfranc joint injury were treated by open reduction and dorsal plate fixation or standard screw fixation. The patients were followed on average for 31 months. Evaluation was performed wit...

  14. Tissue fixation and the effect of molecular fixatives on downstream staining procedures

    OpenAIRE

    Howat, William J.; Wilson, Beverley A.

    2014-01-01

    It is impossible to underplay the importance of fixation in histopathology. Whether the scientist is interested in the extraction of information on lipids, proteins, RNA or DNA, fixation is critical to this extraction. This review aims to give a brief overview of the current “state of play” in fixation and focus on the effect fixation, and particularly the effect of the newer brand of “molecular fixatives” have on morphology, histochemistry, immunohistochemistry and RNA/DNA analysis. A method...

  15. Demineralized Bone Matrix Add-On for Acceleration of Bone Healing in Atypical Subtrochanteric Femoral Fracture: A Consecutive Case-Control Study

    OpenAIRE

    Noratep Kulachote; Paphon Sa-ngasoongsong; Norachart Sirisreetreerux; Pongsthorn Chanplakorn; Praman Fuangfa; Chanyut Suphachatwong; Wiwat Wajanavisit

    2016-01-01

    Background. Delayed union and nonunion are common complications in atypical femoral fractures (AFFs) despite having good fracture fixation. Demineralized bone matrix (DBM) is a successfully proven method for enhancing fracture healing of the long bone fracture and nonunion and should be used in AFFs. This study aimed to compare the outcome after subtrochanteric AFFs (ST-AFFs) fixation with and without DBM. Materials and Methods. A prospective study was conducted on 9 ST-AFFs patients using DB...

  16. A bio-artificial poly([D,L]-lactide-co-glycolide drug-eluting nanofibrous periosteum for segmental long bone open fractures with significant periosteal stripping injuries

    Directory of Open Access Journals (Sweden)

    Chou YC

    2016-03-01

    Full Text Available Ying-Chao Chou,1,2 Yi-Shiun Cheng,1 Yung-Heng Hsu,1,2 Yi-Hsun Yu,1,2 Shih-Jung Liu1,2 1Biomaterials Lab, Department of Mechanical Engineering, Chang Gung University, 2Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan Abstract: Biodegradable poly([D,L]-lactide-co-glycolide (PLGA nanofibrous membrane embedded with two drug-to-polymer weight ratios, namely 1:3 and 1:6, which comprised PLGA 180 mg, lidocaine 20 mg, vancomycin 20 mg, and ceftazidime 20 mg, and PLGA 360 mg, lidocaine 20 mg, vancomycin 20 mg, and ceftazidime 20 mg, respectively, was produced as an artificial periosteum in the treatment of segmental femoral fractures. The nanofibrous membrane’s drug release behavior was assessed in vitro using high-performance liquid chromatography and the disk-diffusion method. A femoral segmental fracture model with intramedullary Kirschner-wire fixation was established for the in vivo rabbit activity study. Twenty-four rabbits were divided into two groups. Twelve rabbits in group A underwent femoral fracture fixation only, and 12 rabbits in group B underwent femoral fracture fixation and were administered the drug-loaded nanofibers. Radiographs obtained at 2, 6, and 12 weeks postoperatively were used to assess the bone unions. The total activity counts in animal behavior cages were also examined to evaluate the clinical performance of the rabbits. After the animals were euthanized, both femoral shafts were harvested and assessed for their torque strengths and toughness. The daily in vitro release curve for lidocaine showed that the nanofibers eluted effective levels of lidocaine for longer than 3 weeks. The bioactivity studies of vancomycin and ceftazidime showed that both antibiotics had effective and sustained bactericidal capacities for over 30 days. The findings from the in vivo animal activity study suggested that the rabbits with the artificial drug-eluting periosteum exhibited statistically increased

  17. Evaluation in effects of poly (L-lactide) miniplates for internal fixation of mandibular fracture

    International Nuclear Information System (INIS)

    Objective: To investigate the internal fixation effects of poly (L-lactide) (PLLA) miniplates on the mandibular fracture in dogs. Methods: A total of 12 dogs were involved in the study. After mandibular fracture models were created on both sides, one side of the mandibular was fixed with PLLA miniplates and the other side was fixed with titanium plates as control. The dogs were sacrificed separately at 1, 3, 6, 12 months after operation, three animals at each time. Gross observation, radiography and histopathological examination were performed. Results: All of the dogs were alive and fracture fixation of both sides was excellent after the operation. Gross observation:in 1 month group, the fracture line and some bony callus could be seen on both sides; in 3 months group, both sides had become into bone union; in 6 months group, both sides had become into bone union completely; in 12 months group, the fracture lines on both sides were difficult to be seen. Radiography examination:in 1 month group, the fracture lines and the screw holes could be seen on both sides; in 3 months group, the fracture lines turned ambiguity; in 6 months group, the line on the experimental side was difficult to be seen but the line on the control side disappeared; in 12 months group, the fracture lines on both sides disappeared. Histopathology examination: in 1 month group, there were lots of collagen fibers and a little bone trabecula on both sides; in 3 months group, the trabecula on the experimental side were much more than the other side; in 6 months group, the bone trabecula on both sides looked like the normal bone tissue; in 12 months group, the bone trabecula became into nomal tissue. Conclusion: The effect of PLLA miniplates for internal fixation of mandibular fracture is safety, the PLLA miniplate can maintain the stability of the bone fracture during the healing process. (authors)

  18. Epoxy putty external skeletal fixation in a tibiotarsal fracture of a wild choroy parakeet (Enicognathus leptorhynchus

    Directory of Open Access Journals (Sweden)

    J. I. Arias

    2015-06-01

    Full Text Available Tibiotarsal fractures are common in birds because in most birds this is the longest, most exposed bone in the leg. Transverse fractures are most common and rotational and shear forces must be stabilized in order to achieve good bone regeneration. A 230g male Slender-billed Parakeet or Choroy parakeet (Enicognathus leptorhynchus, with more than five years of age, was received with non-weight bearing lameness with 24 hours duration. X-rays were taken, and these revealed a closed, complete, non-comminuted transverse fracture of the distal diaphysis of the left tibiotarsal bone. Fixation was planned with 10-minute fast-setting epoxy putty. In order to assess the temperature of polymerization of the epoxy dough and the possibility of heat-bone necrosis, the temperature was recorded every 30 seconds for 12 minutes with three different amounts of the epoxy material in an ex vivo test. The temperature of the pieces reached a peak of 50-60ºC, where the highest peak corresponds to the highest amount of material. When approximately 6g of putty were used, the peak temperature reached only 51ºC. This peak changed to 58ºC when 4 times more epoxy was mixed and measured. If the temperature of the pins inserted in the bone exceeds 70ºC, bone necrosis could occur. In light of these results, the fracture was treated with 6 g of epoxy putty that was allowed to polymerize over a 1A 2/2 external skeletal fixation, with 1-mm pins bent at 90º and joined together with cerclage wire. At 6 weeks after surgery the bird had formed a good primary bone callus, and the external fixators were therefore removed. With this approach a satisfactory recovery of the patient was achieved with normal use of the affected limb.

  19. Improved Reactive Dye-fixation in Pad-Steam Process of Dyeing Cotton Fabric Using Tetrasodium N, NBiscarboxylatomethyl- L-Glutamate

    Directory of Open Access Journals (Sweden)

    Awais Khatri

    2012-04-01

    Full Text Available Pad steam process of dyeing cotton with reactive dyes is known to give lower levels of dye-fixation on the fiber because of excessive dye-hydrolysis. This research presents improved reactive dye-fixation in padsteam process of dyeing cotton found in an effort of using biodegradable organic salts to improve the effluent quality. The CI Reactive Blue 250, a bissulphatoethylsulphone dye and the Tetrasodium N, Nbiscarboxylatomethyl- L-Glutamate, a biodegradable organic salt, were used. The new dye-bath formulation using the organic salt gave more than 90% dye-fixation. Traditional pad-steam process of dyeing cotton with reactive dyes requires the use of inorganic electrolyte, sodium-chloride, and alkali, sodium-carbonate, to ensure effective dye consumption and fixation. These inorganic chemicals when drained generate heavy contents of dissolved solids and oxygen demand in the effluent leading to environmental pollution. Thus, Tetrasodium N, N-biscarboxylatomethyl-L-Glutamate was used in place of inorganic electrolyte and alkali to improve effluent quality. A significant increase in dye-fixation and ultimate color-yield was obtained with same colorfastness properties of the dyed fabric comparing to the traditional pad-steam dye-bath formulation.

  20. Biodegradable congress 2012; Bioschmierstoff-Kongress 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    Within the Guelzower expert discussions at 5th and 6th June, 2012 in Oberhausen (Federal Republic of Germany) the following lectures were held: (1) Promotion of biodegradable lubricants by means of research and development as well as public relations (Steffen Daebeler); (2) Biodegradable lubricants - An overview of the advantages and disadvantages of the engaged product groups (Hubertus Murrenhoff); (3) Standardization of biodegradable lubricants - CEN/DIN standard committees - state of the art (Rolf Luther); (4) Market research for the utilization of biodegradable lubricants and means of proof of sustainability (Norbert Schmitz); (5) Fields of application for high performance lubricants and requirements upon the products (Gunther Kraft); (6) Investigations of biodegradable lubricants in rolling bearings and gears (Christoph Hentschke); (7) Biodegradable lubricants in central lubrication systems Development of gears and bearings of offshore wind power installations (Reiner Wagner); (8) Investigations towards environmental compatibility of biodegradable lubricants used in offshore wind power installations (Tolf Schneider); (9) Development of glycerine based lubricants for the industrial metalworking (Harald Draeger); (10) Investigations and utilization of biodegradable oils as electroinsulation oils in transformers (Stefan Tenbohlen); (11) Operational behaviour of lubricant oils in vegetable oil operation and Biodiesel operation (Horst Hamdorf); (12) Lubrication effect of lubricating oil of the third generation (Stefan Heitzig); (13) Actual market development from the view of a producer of biodegradable lubricants (Frank Lewen); (14) Utilization of biodegradable lubricants in forestry harvesters (Guenther Weise); (15) New biodegradable lubricants based on high oleic sunflower oil (Otto Botz); (16) Integrated fluid concept - optimized technology and service package for users of biodegradable lubricants (Juergen Baer); (17) Utilization of a bio oil sensor to control

  1. Fixation Status of Acid Soils

    International Nuclear Information System (INIS)

    Six acid soil series from different benchmark sites; Rangsit soil (Sulfic Tropaquepts) (two acid sulfate soils), Pakchong soil (Oxic Paleustults) Korat soil (Oxic Paleustults), Warin soil (Oxic Paleustults), Mae Taeng soil (Typic paleustults) and Boundary grey soil and two Thai phosphate rocks (P R) (Lampun P R and Ratchabuie P R) had been characterized in the laboratory by isotope techniques (E, value Part 1). Triple superphosphate (TSP) was used as a standard fertilizer. R P and TSP with 50 mg P Kg-1 soil were incubated for 30 days to examine the fixing capacity of the acid soils. The results showed that Rangsit Soil which is acid sulfate had high fixing capacity. Pakchong soil retained higher P fixation ability than Korat and Warin soil series. The highest fixation capacity among 7 acid soils were Grey Soil and Mae Taeng soil series. The solubility of TSP was decreased when incorporated with soil after incubation for 30 days. P R from Ratchaburi showed higher effectiveness than Lamphun P R

  2. Bone Cancer

    Science.gov (United States)

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  3. Bone Cancer

    Science.gov (United States)

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another part of the body is more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 ...

  4. Bone Diseases

    Science.gov (United States)

    Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly ... childhood and your teens, your body adds new bone faster than it removes old bone. After about ...

  5. Biodegradation kinetics at low concentrations (

    DEFF Research Database (Denmark)

    Toräng, Lars; Albrechtsen, Hans-Jørgen; Nyholm, Niels

    Aerobic biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in groundwater added sediment fines. At concentrations at or below 1 mu g/L of 2,4-D degradation kinetic was of true first order without significant growth of specific degraders and with half-life for mineralization in the...

  6. Biodegradable Pectin/clay Aerogels

    Science.gov (United States)

    Biodegradable, foamlike materials based on renewable pectin and sodium montmorillonite clay were fabricated through a simple, environmentally friendly freeze-drying process. Addition of multivalent cations (Ca2+ and Al3+) resulted in apparent crosslinking of the polymer, and enhancement of aerogel p...

  7. Metaphyseal bone loss in revision knee arthroplasty.

    Science.gov (United States)

    Ponzio, Danielle Y; Austin, Matthew S

    2015-12-01

    The etiology of bone loss encountered during revision total knee arthroplasty (TKA) is often multifactorial and can include stress shielding, osteolysis, osteonecrosis, infection, mechanical loss due to a grossly loose implant, and iatrogenic loss at the time of implant resection. Selection of the reconstructive technique(s) to manage bone deficiency is determined by the location and magnitude of bone loss, ligament integrity, surgeon experience, and patient factors including the potential for additional revision, functional demand, and comorbidities. Smaller, contained defects are reliably managed with bone graft, cement augmented with screw fixation, or modular augments. Large metaphyseal defects require more extensive reconstruction such as impaction bone grafting with or without mesh augmentation, prosthetic augmentation, use of bulk structural allografts, or use of metaphyseal cones or sleeves. While each technique has advantages and disadvantages, the most optimal method for reconstruction of large metaphyseal bone defects during revision TKA is not clearly established. PMID:26362647

  8. Anaerobic biodegradability of fish remains: experimental investigation and parameter estimation.

    Science.gov (United States)

    Donoso-Bravo, Andres; Bindels, Francoise; Gerin, Patrick A; Vande Wouwer, Alain

    2015-01-01

    The generation of organic waste associated with aquaculture fish processing has increased significantly in recent decades. The objective of this study is to evaluate the anaerobic biodegradability of several fish processing fractions, as well as water treatment sludge, for tilapia and sturgeon species cultured in recirculated aquaculture systems. After substrate characterization, the ultimate biodegradability and the hydrolytic rate were estimated by fitting a first-order kinetic model with the biogas production profiles. In general, the first-order model was able to reproduce the biogas profiles properly with a high correlation coefficient. In the case of tilapia, the skin/fin, viscera, head and flesh presented a high level of biodegradability, above 310 mLCH₄gCOD⁻¹, whereas the head and bones showed a low hydrolytic rate. For sturgeon, the results for all fractions were quite similar in terms of both parameters, although viscera presented the lowest values. Both the substrate characterization and the kinetic analysis of the anaerobic degradation may be used as design criteria for implementing anaerobic digestion in a recirculating aquaculture system. PMID:25812103

  9. Outcomes of Ilizarov ring fixation in recalcitrant infected tibial non-unions – a prospective study

    Science.gov (United States)

    Madhusudhan, Thayur R; Ramesh, Balasundaram; Manjunath, KS; Shah, Harshad M; Sundaresh, Dabir C; Krishnappa, N

    2008-01-01

    Background Infected non-union of long bones is a problem in the developing countries. Persistent infection, deformity, shortening, bone loss, joint stiffness and disability complicate the non-union. Secondary procedures are often required for correction of bone defects and deformity. Ilizarov method addresses all the above problems simultaneously and offers a panacea for infected non-unions. The stability of the fixation and provision for bone transport allows bridging of bone defects, limb lengthening, early weight bearing ambulation and joint mobilisation. Aim of the study To know the suitability of this procedure in recalcitrant infected tibial non-unions in the Indian population and the influence of socio-economic factors in the functional outcome. Method of study This was a 3-year prospective study in 22 consecutive patients with an average follow up of 13 months following fracture union. The results were analysed using the ASAMI scoring system. Results Of 22 patients in the study, 13 patients who underwent external bone transport, had an average bone gap of 4 cms [2–11 cms] with an average duration of fixation of 9.3 months [6.5–13 months]. There were 4 excellent, 3 good, 4 fair and 2 poor bony results and 1 excellent, 3 good, 6 fair and 2 poor results. 1 patient was lost for follow up at final functional analysis. 9 patients who underwent internal bone transport had an average bone gap of 5.4 cms [1.5–9 cms] with an average duration of fixation of 8.5 months [4–11 months]. There were 3 good 4 fair and 2 poor bony results and 1 good, 3 fair, and 2 poor functional results. Good to excellent results were witnessed in well-motivated patients with adequate social and financial support. Patients with fair to poor results preferred amputation to limb salvage despite the fact that they retained their limbs. Conclusion Treatment of infected non-unions of Tibia with Ilizarov ring fixation is effective but for optimal results the treatment needs to be

  10. Outcomes of Ilizarov ring fixation in recalcitrant infected tibial non-unions – a prospective study

    Directory of Open Access Journals (Sweden)

    Shah Harshad M

    2008-07-01

    Full Text Available Abstract Background Infected non-union of long bones is a problem in the developing countries. Persistent infection, deformity, shortening, bone loss, joint stiffness and disability complicate the non-union. Secondary procedures are often required for correction of bone defects and deformity. Ilizarov method addresses all the above problems simultaneously and offers a panacea for infected non-unions. The stability of the fixation and provision for bone transport allows bridging of bone defects, limb lengthening, early weight bearing ambulation and joint mobilisation. Aim of the study To know the suitability of this procedure in recalcitrant infected tibial non-unions in the Indian population and the influence of socio-economic factors in the functional outcome. Method of study This was a 3-year prospective study in 22 consecutive patients with an average follow up of 13 months following fracture union. The results were analysed using the ASAMI scoring system. Results Of 22 patients in the study, 13 patients who underwent external bone transport, had an average bone gap of 4 cms [2–11 cms] with an average duration of fixation of 9.3 months [6.5–13 months]. There were 4 excellent, 3 good, 4 fair and 2 poor bony results and 1 excellent, 3 good, 6 fair and 2 poor results. 1 patient was lost for follow up at final functional analysis. 9 patients who underwent internal bone transport had an average bone gap of 5.4 cms [1.5–9 cms] with an average duration of fixation of 8.5 months [4–11 months]. There were 3 good 4 fair and 2 poor bony results and 1 good, 3 fair, and 2 poor functional results. Good to excellent results were witnessed in well-motivated patients with adequate social and financial support. Patients with fair to poor results preferred amputation to limb salvage despite the fact that they retained their limbs. Conclusion Treatment of infected non-unions of Tibia with Ilizarov ring fixation is effective but for optimal results the

  11. Favorable outcome of a total hip arthroplasty with insufficient bone coverage of the roof reinforcement ring

    Directory of Open Access Journals (Sweden)

    Fernando M. Judas

    2015-01-01

    Conclusion: This result can be supported by the good fixation of the metal ring to the pelvis with screws, the adequate orientation of both components of the total hip arthroplasty, and the bone graft incorporation.

  12. Process for fixation of radioactive waste

    International Nuclear Information System (INIS)

    Fixation of radioactive waste comprises mixing of the water saturated waste with a resin and a monomer in order to form an emulsion. By addition of a hydraulic binder, formation of concrete is achieved. This process enables the fixation of the waste in a stable manner without release of radioactivity

  13. Eighth international congress on nitrogen fixation. Final program

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This volume contains the proceedings of the Eighth International Congress on Nitrogen Fixation held May 20--26, 1990 in Knoxville, Tennessee. The volume contains abstracts of individual presentations. Sessions were entitled Recent Advances in the Chemistry of Nitrogen Fixation, Plant-microbe Interactions, Limiting Factors of Nitrogen Fixation, Nitrogen Fixation and the Environment, Bacterial Systems, Nitrogen Fixation in Agriculture and Industry, Plant Function, and Nitrogen Fixation and Evolution.

  14. Effect of Additive on Sulfur-fixation Process of Sulfur-fixation Agent

    Institute of Scientific and Technical Information of China (English)

    XIE Jun-lin; QIU Jian-rong; ZHAO Gai-ju; LOU Jin-ping; HAN Chun-hua

    2003-01-01

    The crystallization behavior of desulfurization product is directly related to its high-temperatureresistant ability. Effects of the additive on the sulfur-fixation efficiency of the Ba-sulfur-fixation agent and also on the crystallization behavior of the sulfur-fixation product were studied when CaCO3 and BaCO3 were used as the desulfurization agent and MgO and SrCO3 used as the assistant sulfur-fixation agent. The result shows that increase of sulfur-fixation capability for the additive is not owe to their directly react to form sulfate or interact with CaCO3 and BaCO3 to form composite mineral heat-resistant in high temperature, but owe to their activation to sulfur-fixation reaction of the sulfur-fixation agent.

  15. MANAGEMENT OF INFECTED NON UNION TIBIAL FRACTURES WITH ILIZAROV EXTERNAL FIXATION

    Directory of Open Access Journals (Sweden)

    Nageshwara Rao

    2015-10-01

    Full Text Available BACKGROUND & OBJECTIVES: Infected non - union of tibia per se is a challenge to treat. Subcutaneous bone causes susceptibility to compartment syndrome, non - responsive infection, non - union, fibrosis, sinuses, deformities, shortening and various other sets of problems which are assoc iated with it. Ilizarov External fixation provides correction of all the complications associated with non - union, bone gap, infection, shortening, and deformities. Objective of this study is to assess the efficacy and safety of Ilizarov fixator method of t reatment in infected non - union tibia and to study various complications associated with Ilizarov external fixation. MATERIALS AND METHODS: 23 patients admitted and treated in Government General Hospital under the Department of Orthopaedics during the perio d of May 2010 to December 2012 were included in the study. Results were evaluated according to ASAMI criteria . 1 RESULTS : 59% patients had excellent bony results, 27.3% had good bony results, 9.1% had fair bony results, 4.6% had poor bony results. 68.1% had excellent functional results, 9.1% had good functional results, 9.1% had fair functional results, 13.7% had poor functional results. CONCLUSION : Ilizarov external fixator system is the best device and best solution for infected non - union tibia management.

  16. Dual fibular grafting - A new technique of fixation of the femoral neck fractures

    Directory of Open Access Journals (Sweden)

    Yadav S

    2005-01-01

    Full Text Available Background: To achieve osteosynthesis of femoral neck fractures is a challenge to the treating surgeon. Plethora of devices and methods has been described. Method: A new technique of achieving union of femoral neck fractures by dual-fibular fixation has been reported in 150 patients. The age of the patients ranged from 6-75 years. Results: Nearly two-third of these were Garden type II and III with an average follow-up of 120 months. In this series 67% had good to excellent long term results. Conclusion: Two fibular struts provide autologous bone, filling the whole of the osteopenic femoral neck and prevent the rotational forces. Since the total fixation is biologically active, the technique has proved advantageous even when stable / desirable reduction is not possible and adequate fixation is not achieved, because of posterior communition at the fracture site or due to osteoporosis. Being autologous bone, the twin-fibular graft is advantageous even when there is ′subsequent loss of reduction′ of the fracture. It is, therefore, suggested that this simple, inexpensive and biological technique has many advantages over the existing methods of fixation of these fractures.

  17. Review of fixation techniques for the four-part fractured proximal humerus in hemiarthroplasty

    Directory of Open Access Journals (Sweden)

    Lorenzetti Silvio

    2011-07-01

    Full Text Available Abstract Introduction The clinical outcome of hemiarthroplasty for proximal humeral fractures is not satisfactory. Secondary fragment dislocation may prevent bone integration; the primary stability by a fixation technique is therefore needed to accomplish tuberosity healing. Present technical comparison of surgical fixation techniques reveals the state-of-the-art approach and highlights promising techniques for enhanced stability. Method A classification of available fixation techniques for three- and four part fractures was done. The placement of sutures and cables was described on the basis of anatomical landmarks such as the rotator cuff tendon insertions, the bicipital groove and the surgical neck. Groups with similar properties were categorized. Results Materials used for fragment fixation include heavy braided sutures and/or metallic cables, which are passed through drilling holes in the bone fragments. The classification resulted in four distinct groups: A: both tuberosities and shaft are fixed together by one suture, B: single tuberosities are independently connected to the shaft and among each other, C: metallic cables are used in addition to the sutures and D: the fragments are connected by short stitches, close to the fragment borderlines. Conclusions A plurality of techniques for the reconstruction of a fractured proximal humerus is found. The categorisation into similar strategies provides a broad overview of present techniques and supports a further development of optimized techniques. Prospective studies are necessary to correlate the technique with the clinical outcome.

  18. Development of a bone tissue-engineered construct to enhance new bone formation in revision total hip replacement

    OpenAIRE

    García Gareta, E.

    2012-01-01

    The main issue associated with revision total hip replacements (rTHRs) is how to generate new bone and restore bone stock for fixation of the revision stem. Bone tissue engineering (BTE) seeks the generation of constructs ex vivo in order to replace damaged or lost bone. The aim of this thesis was to develop a bone tissue-engineered construct with a calcium-phosphate (CaP) coated porous metal scaffold seeded throughout its structure with mesenchymal stem cells (MSCs) in order to enhance new b...

  19. Fibular grafting with cannulated hip screw fixation in late femoral neck fracture in young adults

    Directory of Open Access Journals (Sweden)

    Goyal R

    2006-01-01

    Full Text Available Background: We reviewed the operative results of fibular bone graft with cannulated hip screw fixation in femoral neck fracture in young adults. Method: Sixteen young adults with femoral neck fracture were treated by fibular bone graft with cannulated hip screw fixation. All the fractures were more than 3 weeks old. Results: Results were assessed in 15 patients while one patient died due to complications not related to surgery. Union occurred in all 15 patients. One patient had intra-operative complication in the form of screw cut out with graft in the joint space. The average fallow up was 24.4 months. Out of 15 patients assessed clinico-radiologically 11 showed good results, 3 had fair while 1 had poor result. Conclusion: We conclude that this is a simple and cost effective procedure for late femoral fleck fracture in young adults with good results.

  20. Treatment of Spinal Tuberculosis by Debridement, Interbody Fusion and Internal Fixation via Posterior Approach Only.

    Science.gov (United States)

    Tang, Ming-xing; Zhang, Hong-qi; Wang, Yu-xiang; Guo, Chao-feng; Liu, Jin-yang

    2016-02-01

    Surgical treatment for spinal tuberculosis includes focal tuberculosis debridement, segmental stability reconstruction, neural decompression and kyphotic deformity correction. For the lesions mainly involved anterior and middle column of the spine, anterior operation of debridement and fusion with internal fixation has been becoming the most frequently used surgical technique for the spinal tuberculosis. However, high risk of structural damage might relate with anterior surgery, such as damage in lungs, heart, kidney, ureter and bowel, and the deformity correction is also limited. Due to the organs are in the front of spine, there are less complications in posterior approach. Spinal pedicle screw passes through the spinal three-column structure, which provides more powerful orthopedic forces compared with the vertebral body screw, and the kyphotic deformity correction effect is better in posterior approach. In this paper, we report a 68-year-old male patient with thoracic tuberculosis who underwent surgical treatment by debridement, interbody fusion and internal fixation via posterior approach only. The patient was placed in prone position under general anesthesia. Posterior midline incision was performed, and the posterior spinal construction was exposed. Then place pedicle screw, and fix one side rod temporarily. Make the side of more bone destruction and larger abscess as lesion debridement side. Resect the unilateral facet joint, and retain contralateral structure integrity. Protect the spinal cord, nerve root. Clear sequestrum, necrotic tissue, abscess of paravertebral and intervertebral space. Specially designed titanium mesh cages or bone blocks were implanted into interbody. Fix both side rods and compress both sides to make the mesh cages and bone blocks tight. Reconstruct posterior column structure with allogeneic bone and autologous bone. Using this technique, the procedures of debridement, spinal cord decompression, deformity correction, bone grafting

  1. Radionuclide fixation mechanisms in rocks

    International Nuclear Information System (INIS)

    In the safety evaluation of the radioactive waste disposal in geological environment, the mass balance equation for radionuclide migration is given. The sorption of radionuclides by geological formations is conventionally represented by the retardation of the radionuclides as compared with water movement. In order to quantify the sorption of radionuclides by rocks and sediments, the distribution ratio is used. In order to study quantitatively the long term behavior of waste radionuclides in geological environment, besides the distribution ratio concept in short term, slower radionuclide retention reaction involving mineral transformation should be considered. The development of microspectroscopic method for long term reaction path modeling, the behavior of iron during granite and water interaction, the reduction precipitation of radionuclides, radionuclide migration pathways, and the representative scheme of radionuclide migration and fixation in rocks are discussed. (K.I.)

  2. Temporomandibular joint ankylosis fixation technique with ultra thin silicon sheet

    Directory of Open Access Journals (Sweden)

    G S Kalra

    2011-01-01

    Full Text Available Background: Temporomandibular joint ankylosis is a highly distressing condition in which the joint space is obliterated by scar tissue and the patient has an inability to open the mouth. Different autogenous and alloplastic interposition materials have been used after the resection of the ankylotic bone to achieve desirable and long lasting results. The recurrence of disease is most distressing for both patients and surgeon. We have been using ultra thin silicon sheet as our preferred material for providing proper fixation and cover to the joint. We have been encouraged by good patient compliance, no implant extrusion and favourable outcome. Materials and Methods: The clinical study included 80 patients with temporomandibular joint ankylosis, treated between April 2001 and March 2009. In all patients, temporomandibular joint ankylosis had resulted following trauma. Diagnosis was based on clinical assessment supplemented by radiographic examination consisting of a panoramic radiograph, axial and coronal computer tomography. The technique of using ultra thin silicon sheet covering whole of the joint space fixed with non-absorbable nylon 3-0 suture both medially to medial pterygoid muscle and laterally to periosteum of zygomatic arch was employed in all patients. Results: A total of 80 patients were in this study (59 males and 21 females. The aetiology of temporomandibular joint ankylosis was post-traumatic in all cases. The patients′ age ranged from 5 to 45 years. The disease was unilateral in 61 cases and bilateral in 19 cases. Twelve patients, who had previous surgery done in the form of gap arthroplasty in 6 cases, costochondral graft in 4 cases and temporalis muscle in 2 cases, presented with recurrence on the same side. The pre-op inter-incisal mouth opening ranged from 4 to 12 mm. The intraoperative inter-incisal mouth opening ranged from 28 to 46 mm. An additional procedure was done in 13 patients, including placement of costochondral

  3. Biodegradable radioactive implants for glaucoma filtering surgery produced by ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Assmann, W. [Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, 85748 Garching (Germany)]. E-mail: walter.assmann@lmu.de; Schubert, M. [Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, 85748 Garching (Germany); Held, A. [Augenklinik, Technische Universitaet Muenchen, 81675 Munich (Germany); Pichler, A. [Augenklinik, Technische Universitaet Muenchen, 81675 Muenchen (Germany); Chill, A. [Zentralinstitut fuer Medizintechnik, Technische Universitaet Muenchen, 85748 Garching (Germany); Kiermaier, S. [Zentralinstitut fuer Medizintechnik, Technische Universitaet Muenchen, 85748 Garching (Germany); Schloesser, K. [Forschungszentrum Karlsruhe, 76021 Karlsruhe (Germany); Busch, H. [NTTF GmbH, 53619 Rheinbreitbach (Germany); Schenk, K. [NTTF GmbH, 53619 Rheinbreitbach (Germany); Streufert, D. [Acri.Tec GmbH, 16761 Hennigsdorf (Germany); Lanzl, I. [Augenklinik, Technische Universitaet Muenchen, 81675 Munich (Germany)

    2007-04-15

    A biodegradable, {beta}-emitting implant has been developed and successfully tested which prevents fresh intraocular pressure increase after glaucoma filtering surgery. Ion implantation has been used to load the polymeric implants with the {beta}-emitter {sup 32}P. The influence of ion implantation and gamma sterilisation on degradation and {sup 32}P-fixation behavior has been studied by ion beam and chemical analysis. Irradiation effects due to the applied ion fluence (10{sup 15} ions/cm{sup 2}) and gamma dose (25 kGy) are found to be tolerable.

  4. Biodegradable radioactive implants for glaucoma filtering surgery produced by ion implantation

    International Nuclear Information System (INIS)

    A biodegradable, β-emitting implant has been developed and successfully tested which prevents fresh intraocular pressure increase after glaucoma filtering surgery. Ion implantation has been used to load the polymeric implants with the β-emitter 32P. The influence of ion implantation and gamma sterilisation on degradation and 32P-fixation behavior has been studied by ion beam and chemical analysis. Irradiation effects due to the applied ion fluence (1015 ions/cm2) and gamma dose (25 kGy) are found to be tolerable

  5. Biodegradable radioactive implants for glaucoma filtering surgery produced by ion implantation

    Science.gov (United States)

    Assmann, W.; Schubert, M.; Held, A.; Pichler, A.; Chill, A.; Kiermaier, S.; Schlösser, K.; Busch, H.; Schenk, K.; Streufert, D.; Lanzl, I.

    2007-04-01

    A biodegradable, β-emitting implant has been developed and successfully tested which prevents fresh intraocular pressure increase after glaucoma filtering surgery. Ion implantation has been used to load the polymeric implants with the β-emitter 32P. The influence of ion implantation and gamma sterilisation on degradation and 32P-fixation behavior has been studied by ion beam and chemical analysis. Irradiation effects due to the applied ion fluence (1015 ions/cm2) and gamma dose (25 kGy) are found to be tolerable.

  6. Allogenic bone rods with freeze drying and gamma rays irradiation for treatment of fracture

    International Nuclear Information System (INIS)

    Opened reduction and internal fixation are the usual treatment of fracture, but both methods need a second operation for removal implants. The benefits of the bone rods are that they can avoid the removement of internal fixation and will be absorbed spontaneously. The bone rods are made of allogeneic compact bones with freeze-drying and gamma rays irradiation supplied by Shanxi Provincial Tissue Bank. The purpose of this study is to evaluate allograft reaction, the stability of the internal fixation, osteoinduction in the treatment of fracture using allogeneic bone rods with freeze drying and gamma rays irradiation. From May 1997 to May 1998, fourteen cases (male 12, female 2) of treatment were reviewed. The mean age was 37.3 (21-5 1). There were 3 medial malleolus fractures, 7 tibia and fibula fractures, 1 ulna and radius fracture, 1 lateral condyle of humerus fracture. The clinical results were satisfactory. Because the strength of the bone rods are weaker than that of screws, the bone rods are only indicated in the fixation of cancellous bones fracture and unloaded bone fracture. It can be used as a supplementary fixation of loaded bone. It is not indicated for fixation of comminuted fracture. More than two bone rods may be used in the fixation of fracture in order to get stability of the fracture and decrease stress between rods which will prevent the break of the bone rods. Allogeneic bone rods with freeze-drying and gamma rays irradiation can be used as implants of non-immunogenicity. There are no allograft reactions in all cases (including fever, leukocytosis, exudation or swelling in the wound). Although plenty of experimental studies have showed that freeze drying with gamma rays irradiation (below 50 KGy) would not destroy BMP of bone allograft, but there is no osteoinduction in our cases. The healing of a fracture and bridging external callus are similar as other operations. This new technique may have the following advantages compare with the screws: 1

  7. Synthesis, mechanical properties, biocompatibility, and biodegradation of polyurethane networks from lysine polyisocyanates.

    Science.gov (United States)

    Guelcher, Scott A; Srinivasan, Abiraman; Dumas, Jerald E; Didier, Jonathan E; McBride, Sean; Hollinger, Jeffrey O

    2008-04-01

    Bone defects, such as compressive fractures in the vertebral bodies, are frequently treated with acrylic bone cements (e.g., PMMA). Although these biomaterials have sufficient mechanical properties for fixing the fracture, they are non-degradable and do not remodel or integrate with host tissue. In an alternative approach, biodegradable polyurethane (PUR) networks have been synthesized that are designed to integrate with host tissue and degrade to non-cytotoxic decomposition products. PUR networks have been prepared by two-component reactive liquid molding of low-viscosity quasi-prepolymers derived from lysine polyisocyanates and poly(epsilon-caprolactone-co-DL-lactide-co-glycolide) triols. The composition, thermal transitions, and mechanical properties of the biomaterials were measured. The values of Young's modulus ranged from 1.20-1.43 GPa, and the compressive yield strength varied from 82 to 111 MPa, which is comparable to the strength of PMMA bone cements. In vitro, the materials underwent controlled biodegradation to non-cytotoxic decomposition products, and supported the attachment and proliferation of MC3T3 cells. When cultured in osteogenic medium on the PUR networks, MC3T3 cells deposited mineralized extracellular matrix, as evidenced by von Kossa staining and tetracycline labeling. Considering the favorable mechanical and biological properties, as well as the low-viscosity of the reactive intermediates used to prepare the PUR networks, these biomaterials are potentially useful as injectable, biodegradable bone cements for fracture healing. PMID:18255140

  8. 中空加压螺钉及带旋髂深血管髂骨移位对青壮年股骨颈骨折髋关节功能恢复的影响%Effect of canulate compression bone screws and iliac bone flap with deep iliac circumflex vessel on functional restoration of hip joint after femoral neck fracture of young people

    Institute of Scientific and Technical Information of China (English)

    袁宏伟; 叶应荣

    2002-01-01

    Objective To retrospect therapeutic effects of iliac flap with deep iliac circumflex vessel with canulate compression bone screws internal fixation on femoral neck fracture of young people. Method 34 cases of femoral neck fracture had been treated with pedicle bone flap with deep iliac circumflex artery and canulate bone screws internal fixation. Result By follow-up for 1 to 1.5 years, 32 cases were healing by first intention, and patients obtained satisfactory joint function. Conclusion Femoral neck fracture can be treated by transplanting pedicle bone flap with deep iliac circumflex vessel and canulate bone screws internal fixation.

  9. Appraisal of logicality and safety of intramedullary fixation of paediatric diaphyseal fractures by titanium elastic nails

    Directory of Open Access Journals (Sweden)

    Arun Vashisht

    2016-03-01

    Conclusions: The intramedullary fixation of paediatric bones with TENs appears quite logical in terms of fracture stability for early mobilisation, early return to school, lesser hospital stay, and lesser parental off-duty. The technique is safe, does not interfere with fracture healing and does not violate the physis as nails are not passed through the physis. [Int J Res Med Sci 2016; 4(3.000: 866-870

  10. Humeral repair in birds by guided tissue regeneration and external and internal associated fixation techniques

    International Nuclear Information System (INIS)

    Ten pigeons (Columba livia domestic form) with humeral diaphyseal fracture were treated with external and internal fixation techniques (Boston technique and intamedullary pin). Longitudinal space was intentionally left between fracture surfaces during osteosynthesis. This space was filled with bovine lyophilized collagen, set around an intramedullary pin, in five samples. Ossification process was checked by radiography every seven days. Results show the utility of this technique in pneumatic bird bones. In fact, shortening control and callus formation facility were observed

  11. Early Weight-bearing Using Percutaneous External Fixator for Calcaneal Fracture

    OpenAIRE

    Sengodan, Vetrivel Chezian; Sengodan, Mugundhan Moongilpatti

    2012-01-01

    Calcaneal fracture, the most common tarsal bone fracture, occurs predominantly in manual labors and subsequently has got considerable socioeconomic implications. Treatment modality which can offer early weight bearing and early return to work is therefore needed for those patients. We have used a biplanar percutaneous external fixator for treating calcaneal fractures without operative and per operative visualization of the fractures. We have treated 17 calcaneal fractures in 16 patients, 12 i...

  12. INTERNAL FIXATION OF INTRA ARTICULAR CALCANEUM FRACTURES USING LOCKING COMPRESSION PLATE

    OpenAIRE

    Neelakrishnan; Balamurugavel; Barathiselvan; Viswanathan

    2014-01-01

    INTRODUCTION: Calcaneum is the most frequently fractured tarsal bone. Historically intra articular calcaneum fractures treated non-operatively which led to increased morbidity due to in congruency of articular surface resulting in subtalar arthritis. With advent of CT scan, better implants and improved methods of fixation. Operative treatment has now become a standard method. AIM OF THE STUDY: To study the functional and radiological outcome of intra articular calcaneum fr...

  13. Biobased and biodegradable polymer nanocomposites

    Science.gov (United States)

    Qiu, Kaiyan

    In this dissertation, various noncrosslinked and crosslinked biobased and biodegradable polymer nanocomposites were fabricated and characterized. The properties of these polymer nanocomposites, and their relating mechanisms and corresponding applications were studied and discussed in depth. Chapter 1 introduces the research background and objectives of the current research. Chapter 2 presents the development of a novel low cost carbon source for bacterial cellulose (BC) production and fabrication and characterization of biobased polymer nanocomposites using produced BC and soy protein based resins. The carbon source, soy flour extract (SFE), was obtained from defatted soy flour (SF) and BC yield achieved using SFE medium was high. The results of this study showed that SFE consists of five sugars and Acetobacter xylinum metabolized sugars in a specific order. Chapter 3 discusses the fabrication and characterization of biodegradable polymer nanocomposites using BC and polyvinyl alcohol (PVA). These polymer nanocomposites had excellent tensile and thermal properties. Crosslinking of PVA using glutaraldehyde (GA) not only increased the mechanical and thermal properties but the water-resistance. Chapter 4 describes the development and characterization of microfibrillated cellulose (MFC) based biodegradable polymer nanocomposites by blending MFC suspension with PVA. Chemical crosslinking of the polymer nanocomposites was carried out using glyoxal to increase the mechanical and thermal properties as well as to make the PVA partially water-insoluble. Chapter 5 reports the development and characterization of halloysite nanotube (HNT) reinforced biodegradable polymer nanocomposites utilizing HNT dispersion and PVA. Several separation techniques were used to obtain individualized HNT dispersion. The results indicated uniform dispersion of HNTs in both PVA and malonic acid (MA) crosslinked PVA resulted in excellent mechanical and thermal properties of the materials, especially

  14. Dinitrogen fixation in aphotic oxygenated marine environments

    Directory of Open Access Journals (Sweden)

    Eyal eRahav

    2013-08-01

    Full Text Available We measured N2 fixation rates from oceanic zones that have traditionally been ignored as sources of biological N2 fixation; the aphotic, fully oxygenated, nitrate (NO3--rich, waters of the oligotrophic Levantine Basin (LB and the Gulf of Aqaba (GA. N2 fixation rates measured from pelagic aphotic waters to depths up to 720 m, during the mixed and stratified periods, ranged from 0.01 nmol N L-1 d-1 to 0.38 nmol N L-1 d-1. N2 fixation rates correlated significantly with bacterial productivity and heterotrophic diazotrophs were identified from aphotic as well as photic depths. Dissolved free amino acid amendments to whole water from the GA enhanced bacterial productivity by 2to 3.5 and N2 fixation rates by ~ 2 fold in samples collected from aphotic depths while in amendments to water from photic depths bacterial productivity increased 2 to 6 fold while N2 fixation rates increased by a factor of 2 to 4 illustrating that both BP an heterotrophic N2 fixation are carbon limited. Experimental manipulations of aphotic waters from the LB demonstrated a significant positive correlation between transparent exopolymeric particles (TEP concentration and N2 fixation rates. This suggests that sinking organic material and high carbon (C: nitrogen (N micro-environments (such as TEP-based aggregates or marine snow could support high heterotrophic N2 fixation rates in oxygenated surface waters and in the aphotic zones. Indeed, our calculations show that aphotic N2 fixation accounted for 37 to 75 % of the total daily integrated N2 fixation rates at both locations in the Mediterranean and Red Seas with rates equal or greater to those measured from the photic layers. Moreover, our results indicate that that while N2 fixation may be limited in the surface waters, aphotic, pelagic N2 fixation may contribute significantly to new N inputs in other oligotrophic basins, yet it is currently not included in regional or global N budgets.

  15. Adjunctive hyperbaric oxygen therapy in the treatment of atrophic tibial nonunion with Ilizarov external fixator: a radiographic and scintigraphic study in rabbits*

    OpenAIRE

    Kurklu, Mustafa; Yurttas, Yuksel; Kose, Ozkan; Demiralp, Bahtiyar; Yuksel, Halil Yalcin; Komurcu, Mahmut

    2012-01-01

    Objective: The aim of this experimental study was to determine the effects of adjunctive hyperbaric oxygen therapy (HBO) on atrophic tibial nonunion treatment using Ilizarov external fixator. Methods: Twenty New Zealand white rabbits were randomly divided into two equal groups. A circular external fixator was applied to the right tibia of all the rabbits. A 5-mm bone block was resected and a tibial pseudarthrosis was obtained after a 6-month waiting period. The experimental group rabbits ...

  16. Micromotion in knee arthroplasty. A roentgen stereophotogrammetric analysis of four different concepts of prosthetic fixation

    International Nuclear Information System (INIS)

    In a prospective study, micromotion between tibial components and bone was analysed using roentgen stereophotogrammetric analysis (RSA), the potential of which was assessed. The patient material consisted of 96 arthrotic knees subjected to arthroplasty with six types of prosthese representing four different fixation concepts with and without bone cement. Provided stable conditions of the objects studied, RSA proved to have an accuracy (=resolution) of 0.3 degrees for rotation and 0.2 mm for translation (3 S.D.). This resolution was 10 times better than conventional radiography and sufficient for the study of micromotion. Micromotion, both gradual over time (migration) and instant, in response to applied forces (inducible displacement), was found for all tibial components studied. For conventional cemented prostheses the mean migration was 1-1.5 mm for the different groups. Most of the migration occurred during the first 6 months. Inducible displacement of 0.2-1.0 mm was found in most cases. Metal support did not improve the prosthetic fixation. For the non-cemented cases both migration and inducible displacement was significantly larger than in cemented cases. All prostheses proved to be bonded to the bone in a semi-rigid way permitting micromotion. The newer fixation concept did not prove superior to conventional cementing of all-polyethylene prostheses. The micromotion occurred wihtin the soft tissue layer constituing the radiolucent zone, which in some cases was of tensile origin. Other radiographic of clinical variables did not correlate with the micromotion. (Author)

  17. Effects of Lateral Mass Screw Rod Fixation to the Stability of Cervical Spine after Laminectomy

    Science.gov (United States)

    Rosli, Ruwaida; Kashani, Jamal; Kadir, Mohammed Rafiq Abdul

    There are many cases of injury in the cervical spine due to degenerative disorder, trauma or instability. This condition may produce pressure on the spinal cord or on the nerve coming from the spine. The aim of this study was, to analyze the stabilization of the cervical spine after undergoing laminectomy via computational simulation. For that purpose, a three-dimensional finite element (FE) model for the multilevel cervical spine segment (C1-C7) was developed using computed tomography (CT) data. There are various decompression techniques that can be applied to overcome the injury. Usually, decompression procedures will create an unstable spine. Therefore, in these situations, the spine is often surgically restabilized by using fusion and instrumentation. In this study, a lateral mass screw-rod fixation was created to stabilize the cervical spine after laminectomy. Material properties of the titanium alloy were assigned on the implants. The requirements moments and boundary conditions were applied on simulated implanted bone. Result showed that the bone without implant has a higher flexion and extension angle in comparison to the bone with implant under applied 1Nm moment. The bone without implant has maximum stress distribution at the vertebrae and ligaments. However, the bone with implant has maximum stress distribution at the screws and rods. Overall, the lateral mass screw-rod fixation provides stability to the cervical spine after undergoing laminectomy.

  18. Salient in space, salient in time: Fixation probability predicts fixation duration during natural scene viewing.

    Science.gov (United States)

    Einhäuser, Wolfgang; Nuthmann, Antje

    2016-09-01

    During natural scene viewing, humans typically attend and fixate selected locations for about 200-400 ms. Two variables characterize such "overt" attention: the probability of a location being fixated, and the fixation's duration. Both variables have been widely researched, but little is known about their relation. We use a two-step approach to investigate the relation between fixation probability and duration. In the first step, we use a large corpus of fixation data. We demonstrate that fixation probability (empirical salience) predicts fixation duration across different observers and tasks. Linear mixed-effects modeling shows that this relation is explained neither by joint dependencies on simple image features (luminance, contrast, edge density) nor by spatial biases (central bias). In the second step, we experimentally manipulate some of these features. We find that fixation probability from the corpus data still predicts fixation duration for this new set of experimental data. This holds even if stimuli are deprived of low-level images features, as long as higher level scene structure remains intact. Together, this shows a robust relation between fixation duration and probability, which does not depend on simple image features. Moreover, the study exemplifies the combination of empirical research on a large corpus of data with targeted experimental manipulations. PMID:27627736

  19. Kennedy Space Center Fixation Tube (KFT)

    Science.gov (United States)

    Richards, Stephanie E.; Levine, Howard G.; Romero, Vergel

    2016-01-01

    Experiments performed on the International Space Station (ISS) frequently require the experimental organisms to be preserved until they can be returned to earth for analysis in the appropriate laboratory facility. The Kennedy Fixation Tube (KFT) was developed to allow astronauts to apply fixative, chemical compounds that are often toxic, to biological samples without the use of a glovebox while maintaining three levels of containment (Fig. 1). KFTs have been used over 200 times on-orbit with no leaks of chemical fixative. The KFT is composed of the following elements: a polycarbonate main tube where the fixative is loaded preflight, the sample tube where the plant or other biological specimens is placed during operations, the expansion plug, actuator, and base plug that provides fixative containment (Fig. 2). The main tube is pre-filled with 25 mL of fixative solution prior to flight. When actuated, the specimen contained within the sample tube is immersed with approximately 22 mL (+/- 2 mL) of the fixative solution. The KFT has been demonstrated to maintain its containment at ambient temperatures, 4degC refrigeration and -100 C freezing conditions.

  20. BIODEGRADABLE COATING FROM AGATHIS ALBA

    Directory of Open Access Journals (Sweden)

    NORYAWATI MULYONO

    2012-11-01

    Full Text Available The adhesive property of copal makes it as a potential coating onto aluminum foil to replace polyethylene. This research aimed to develop copal-based coating. The coating was prepared by extracting the copal in ethyl acetate and dipping the aluminium foil in ethyl acetate soluble extract of copal. The characterization of coating included its thickness, weight, thermal and chemical resistance, and biodegradation. The results showed that the coating thickness and weight increased as the copal concentration and dipping frequency increased. Thermal resistance test showed that the coating melted after being heated at 110°C for 30 min. Copal-based coating wasresistant to acidic solution (pH 4.0, water, and coconut oil, but was deteriorated in detergent 1% (w/v and basic solution (pH 10.0. Biodegradability test using Pseudomonas aeruginosa showed weight reduction of 76.82% in 30 days.

  1. Simultaneous mechanical property and biodegradation improvement of wollastonite bioceramic through magnesium dilute doping.

    Science.gov (United States)

    Xie, Jiajun; Yang, Xianyan; Shao, Huifeng; Ye, Juan; He, Yong; Fu, Jianzhong; Gao, Changyou; Gou, Zhongru

    2016-02-01

    The large-area bone defects in head (including calvarial, orbital, and maxillofacial bone) and segmental bone are attracting increased attention in a wide range of clinical departments. A key requirement for the clinical success of the bioactive ceramics is the match of the mechanical behavior of the implants with the specific bone tissue to be filled. This raises the question as to what design strategy might be the best indicators for the balance between mechanical properties and biological performances. Here we go beyond the traditional approaches that use phase conversion or biphasic hybrid; instead, we achieved a simultaneous enhancement of several mechanical parameters and optimalization of biodegradability by using a dilute doping of Mg in a single-phase wollastonite bioceramic. We show that the wollastonite ceramic can be rationally tuned in phase (α or β), mechanical strength (in compression and bending mode), elastic modulus (18-23GPa), and fracture toughness (>3.2MPam(1/2)) through the usage of Mg dopant introduced at precisely defined dilute concentrations (Mg/Ca molar ratio: 1.2-2.1%). Meanwhile, the dilute Mg-doped wollastonite ceramics are shown to exhibit good bioactivity in vitro in SBF but biodegradation in Tris is inversely proportional to Mg content. Consequently, such new highly bioactive ceramics with appreciable strength and toughness are promising for making specific porous scaffolds for enhancing large segmental bone defect and thin-wall bone defect repair. PMID:26426432

  2. Biodegradation of Polycyclic Aromatic Hydrocarbons

    OpenAIRE

    DEMİR, İsmail; DEMİRBAĞ, Zihni

    1999-01-01

    Polycylic aromatic hydrocarbons (PAHs), such as petroleum and petroleum derivatives, are widespread organic pollutants entering the environment, chiefly, through oil spills and incomplete combustion of fossil fuels. Since most PAHs are persist in the environment for a long period of time and bioaccumulate, they cause environmental pollution and effect biological equilibrium dramatically. Biodegradation of some PAHs by microorganisms has been biochemically and genetically investigated. Ge...

  3. Biodegradable lubricants for road vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, J. [Denmark Technical Univ., Lyngby (Denmark). Dept. of Mechanical Engineering

    2004-07-01

    This presentation outlined the characteristics of biolubricants and their use in vehicles. Experiments with compression ignition (CI) and spark ignition (SI) engines were also presented. Biolubes can be used in 4-stroke and 2-stroke engines, bearing compressors and hydraulic equipment. Studies have shown that biolubes do not cause unusual engine wear. They are produced from biomass, with the base material being vegetable oils and synthetic esters. Conventional lubricants are produced from fossil fuels, with the base material being mineral oils, polyglycol or synthetic ester. This presentation rated the characteristics of various lubricants in terms of viscosity temperature behaviour, low temperature behaviour, liquid range, oxidation stability, thermal stability, volatility, fire resistance, hydrolytic stability, corrosion protection, seal material compatibility, paints compatibility, miscibility with mineral oil, solubility of additives, lubricating properties, toxicity, and biodegradability. The environmental impacts of biolubes regarding emissions of carbon dioxide, nitrous oxide and particulate matter were discussed along with the impact of combining biolubes with alternative fuels. The future beneficial applications include outboard engines, off road vehicle engines and road vehicle engines. Currently, vegetable oil based biolubricants are 2 to 3 times more expensive than mineral based oils, and synthetic lubricants are even more expensive. It was suggested that future studies should examine the biodegradability of used lubricants, the performance of biodegradable lubricants, alternative fuels and fuel economy. tabs., figs.

  4. Engineering Flame Retardant Biodegradable Nanocomposites

    Science.gov (United States)

    He, Shan; Yang, Kai; Guo, Yichen; Zhang, Linxi; Pack, Seongchan; Davis, Rachel; Lewin, Menahem; Ade, Harald; Korach, Chad; Kashiwagi, Takashi; Rafailovich, Miriam

    2013-03-01

    Cellulose-based PLA/PBAT polymer blends can potentially be a promising class of biodegradable nanocomposites. Adding cellulose fiber reinforcement can improve mechanical properties of biodegradable plastics, but homogeneously dispersing hydrophilic cellulose in the hydrophobic polymer matrix poses a significant challenge. We here show that resorcinol diphenyl phosphates (RDP) can be used to modify the surface energy, not only reducing phase separation between two polymer kinds but also allowing the cellulose particles and the Halloysite clay to be easily dispersed within polymer matrices to achieve synergy effect using melt blending. Here in this study we describe the use of cellulose fiber and Halloysite clay, coated with RDP surfactant, in producing the flame retardant polymer blends of PBAT(Ecoflex) and PLA which can pass the stringent UL-94 V0 test. We also utilized FTIR, SEM and AFM nanoindentation to elucidate the role RDP plays in improving the compatibility of biodegradable polymers, and to determine structure property of chars that resulted in composites that could have optimized mechanical and thermal properties. Supported by Garcia Polymer Center and NSF Foundation.

  5. Radiation effects on biodegradable polyesters

    International Nuclear Information System (INIS)

    Poly(3-hydroxybutyrate) [P(3HB)] and its copolymer poly(3-hydroxybutyrate-co-3hydroxyvalerate) [P(3HB-co-3HV)] are microbial biodegradable polyesters produced by many types of bacteria. Poly(butylene succinate) (PBS) and poly(E-caprolactone) (PCL) are also biodegradable synthetic polyesters which have been commercialized. These thermoplastics are expected for wide usage in environmental protection and blocompatible applications. Radiation grafting of hydrophilic monomers onto many polymers, e.g., polyethylene and polypropylene has been studied mainly for biomedical applications. In the present study, radiation-induced graft polymerization of vinyl monomers onto PHB and P(3HB-co-3HV) was carried out and improvement of their properties was studied. Changes in the properties and biodegradability were compared with the degree of grafting. Radiation-induced crosslinking of PBS and PCL which relatively show thermal and irradiation stability was also carried out to improve their thermal stability or processability. Irradiation to PBS and PCL mainly resulted in crosslinking and characterization of these crosslinked polyesters was investigated

  6. 14CO2 fixation pattern of cyanobacteria

    International Nuclear Information System (INIS)

    The 14CO2 fixation pattern of three cyanobacteria in the light and dark were studied. Two different chromatographic methods widely used for separating labelled photosynthetic intermediates were compared. After ethanolic extraction, a rather uniform fixation pattern reflecting mainly the β-carboxylation pathway is obtained for all 3 species. Of the intermediates, glucosylglycerol is specific and high citrulline and low malate contents are fairly specific to cyanobacteria. The composition of the 14CO2 fixation pattern is hardly affected by changes in temperature or light intensity, but it is severely affected by changes in the water potential of the medium. (author)

  7. Design and clinical application of cervical hollow threaded fixator

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective Cervical hollow threaded fixator (CHTY) was designed and applied to stabilize tha cervical spine following anterior decompression due to cervical spondylosis or acute cervical disc herniation. Methods Medical use titanium alloy with no magnetism was made into a hollow threaded structure with holes on the wall of the fixator. Forly-two patients with cervical spondylosis and acute cervical disc herniation were stabilized using the CHTF technique after anterior decompression. X-ray films and CT scans were taken after the oberation to observe the stability ann fusion rate of the segments. Results Patients were allowed to walk one day after the operation and were followed up for 6 to 36 months. The operated segments were stable and solid fusion was observed 3-6 months after surgery. Conclusions Immediate stability of the operated segments can be obtained using the CHTF technique. Patients ware easy to manage after5 the operation and returned to their jobs in a short time.The CHTF technique is safe and simpa to perfoirme and eliminates the complications of an autograft.It may be an alternative to traditional cervical interbody fusion with bone graft.

  8. Biomechanical analysis of tibia – double threaded screw fixation

    Directory of Open Access Journals (Sweden)

    W. Walke

    2008-03-01

    Full Text Available Purpose: The aim of the work was determination of biomechanical characteristics of a tibia – double threaded screw system with the use of finite element method.Design/methodology/approach: Geometrical model of the tibia was worked out on the basis of data from computer tomography of real bone. Geometrical model of the double threaded screw was prepared in ANSYS v. 11. Meshing was realized with the use of SOLID95 elements, applied in analyses of volumes. The model was loaded with forces in the range F = 100-2000 N.Findings: Initial biomechanical analysis, carried out with the use of finite element method, showed usefulness of the analyzed form of the double threaded screw made of Ti6Al4V alloy in fractured tibia treatment.Research limitations/implications: Due to applied simplifications of the tibia – double threaded screw fixation model, the analysis results should be experimentally verified in laboratory conditions.Originality/value: The obtained biomechanical characteristics of the tibia – double threaded screw system (u = f(F, σmax = f(F are the basis for selection of degree of strain hardening of the applied metallic biomaterial and optimization of geometrical features of the analyzed form of implant. Appropriate selection of mechanical properties and geometrical features of the implant is the main factor determining a stability of the fixation.

  9. Stiffness of modified Type 1a linear external skeletal fixators.

    Science.gov (United States)

    Reaugh, H F; Rochat, M C; Bruce, C W; Galloway, D S; Payton, M E

    2007-01-01

    Modifications of a Type 1a external skeletal fixator (ESF) frame were evaluated by alternately placing transfixation pins on opposite sides of the connecting rod (Type 1a-MOD) or by placing additional connecting rods on either of the two inside (Type 1a-INSIDE) or two outside (Type 1a-OUTSIDE) transfixation pins. The objective of this study was to evaluate the stiffness of these modifications in terms of axial compression (AC), cranial-caudal bending (CCB), and medial-lateral bending (MLB). We hypothesized that these designs would allow significant increase in unilateral frame stiffness, over Type 1a, without proportional increase in frame complexity or technical difficulty of application. All of the ESF frames were constructed using large IMEX SKtrade mark clamps, 3.2 mm threaded fixation pins, 9.5 mm carbon fibre connecting rods and Delrin rods as bone models. Nine, eight pin frames of each design were constructed, and subjected to repetitive non-destructive loading forces (AC, CCB, MLB) using a materials testing machine. Frame construct stiffness for each force (AC, CCB, MLB) was derived from load-deformation curve analysis and displayed in N/mm. Data revealed the 1a-MOD and 1a-OUTSIDE constructs had significantly increased stiffness in CCB and AC as compared to the Type 1a constructs while all of the modified constructs were significantly stiffer in MLB than the Type 1a constructs. PMID:18038001

  10. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  11. Acrylic bone cements modified with bioactive and biodegradable fillers

    OpenAIRE

    Lopes, Poliana Pollizello

    2012-01-01

    O cimento ósseo acrílico é o único material utilizado para a fixação de próteses em cirurgias ortopédicas, surgindo como uma alternativa às técnicas não cimentadas. Cerca de um milhão de pacientes são anualmente tratados para a substituição total da articulação do quadril e do joelho. Com a maior expectativa de vida da população e o aumento do número de cirurgias realizadas por ano espera-se que o uso do cimento ósseo aumente substancialmente. A fraca ligação do cimento a...

  12. Distal Humeral Fixation of an Intramedullary Nail Periprosthetic Fracture

    Directory of Open Access Journals (Sweden)

    Hiren M. Divecha

    2013-01-01

    Full Text Available Distal humeral periprosthetic fractures below intramedullary nail devices are complex and challenging to treat, in particular due to the osteopenic/porotic nature of bone found in these patients. Fixation is often difficult to satisfactorily achieve around the intramedullary device, whilst minimising soft tissue disruption. Descriptions of such cases in the current literature are very rare. We present the case of a midshaft humeral fracture treated with a locking compression plate that developed a nonunion, in a 60-year old female. This went on to successful union after exchange for an intramedullary humeral nail. Unfortunately, the patient developed a distal 1/5th humeral periprosthetic fracture, which was then successfully addressed with a single-contoured, extra-articular, distal humeral locking compression plate (Synthes with unicortical locking screws and cerclage cables proximally around the distal nail tip region. An excellent postoperative range of motion was achieved.

  13. The use of augmentation techniques in osteoporotic fracture fixation.

    Science.gov (United States)

    Kammerlander, Christian; Neuerburg, Carl; Verlaan, Jorrit-Jan; Schmoelz, Werner; Miclau, Theodore; Larsson, Sune

    2016-06-01

    There are an increasing number of fragility fractures, which present a surgical challenge given the reduced bone quality of underlying osteoporosis. Particularly in aged patients, there is a need for early weight bearing and mobilization to avoid further complications such as loss of function or autonomy. As an attempt to improve fracture stability and ultimate healing, the use of biomaterials for augmentation of osseous voids and fracture fixation is a promising treatment option. Augmentation techniques can be applied in various locations, and fractures of the metaphyseal regions such as proximal humerus, femur, tibia and the distal radius remain the most common areas for its use. The current review, based on the available mechanical and biological data, provides an overview of the relevant treatment options and different composites used for augmentation of osteoporotic fractures. PMID:27338226

  14. Neural correlates of fixation duration in natural reading: Evidence from fixation-related fMRI.

    Science.gov (United States)

    Henderson, John M; Choi, Wonil; Luke, Steven G; Desai, Rutvik H

    2015-10-01

    A key assumption of current theories of natural reading is that fixation duration reflects underlying attentional, language, and cognitive processes associated with text comprehension. The neurocognitive correlates of this relationship are currently unknown. To investigate this relationship, we compared neural activation associated with fixation duration in passage reading and a pseudo-reading control condition. The results showed that fixation duration was associated with activation in oculomotor and language areas during text reading. Fixation duration during pseudo-reading, on the other hand, showed greater involvement of frontal control regions, suggesting flexibility and task dependency of the eye movement network. Consistent with current models, these results provide support for the hypothesis that fixation duration in reading reflects attentional engagement and language processing. The results also demonstrate that fixation-related fMRI provides a method for investigating the neurocognitive bases of natural reading. PMID:26151101

  15. Biodegradation of high molecular weight polylactic acid

    OpenAIRE

    Stloukal, Petr; Koutný, Marek; Sedlařík, Vladimír; Kucharczyk, Pavel

    2012-01-01

    Polylactid acid seems to be an appropriate replacement of conventional non-biodegradable synthetic polymer primarily due to comparable mechanical, thermal and processing properties in its high molecular weight form. Biodegradation of high molecular PLA was studied in compost for various forms differing in their specific surface area. The material proved its good biodegradability under composting conditions and all investigated forms showed to be acceptable for industrial composting. Despite e...

  16. Biodegradable materials as foundry moulding sands binders

    OpenAIRE

    K. Major-Gabryś

    2015-01-01

    The aim of this article is to show the possibility of using biodegradable materials as part of the composition of foundry moulding and core sand binders. Research shows that moulding sands with biodegradable materials selected as binders are not only less toxic but are also better suited to mechanical reclamation than moulding sands with phenol-furfuryl resin. The use of biodegradable materials as additives to typical synthetic resins can result in their decreased toxicity and improved abilit...

  17. The materials used in bone tissue engineering

    International Nuclear Information System (INIS)

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone

  18. The materials used in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Tereshchenko, V. P., E-mail: tervp@ngs.ru; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M. [Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan, Novosibirsk (Russian Federation)

    2015-11-17

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

  19. Design, characterisation and in vivo testing of a new, adjustable stiffness, external fixator for the rat femur

    Directory of Open Access Journals (Sweden)

    V Glatt

    2012-04-01

    Full Text Available Very little is known about the influence of the mechanical environment on the healing of large segmental defects. This partly reflects the lack of standardised, well characterised technologies to enable such studies. Here we report the design, construction and characterisation of a novel external fixator for use in conjunction with rat femoral defects. This device not only imposes a predetermined axial stiffness on the lesion, but also enables the stiffness to be changed during the healing process. The main frame of the fixator consists of polyethylethylketone with titanium alloy mounting pins. The stiffness of the fixator is determined by interchangeable connection elements of different thicknesses. Fixators were shown to stabilise 5 mm femoral defects in rats in vivo for at least 8 weeks during unrestricted cage activity. No distortion or infections, including pin infections, were noted. The healing process was simulated in vitro by inserting into a 5 mm femoral defect, materials whose Young’s moduli approximated those of the different tissues present in regenerating bone. These studies confirmed that, although the external fixator is the major determinant of axial stiffness during the early phase of healing, the regenerate within the lesion subsequently dominates this property. There is much clinical interest in altering the mechanics of the defect to enhance bone healing. Our data suggest that, if alteration of the mechanical environment is to be used to modulate the healing of large segmental defects, this needs to be performed before the tissue properties become dominant.

  20. Biodegradable materials as foundry moulding sands binders

    Directory of Open Access Journals (Sweden)

    K. Major - Gabryś

    2015-07-01

    Full Text Available The aim of this article is to show the possibility of using biodegradable materials as part of the composition of foundry moulding and core sand binders. Research shows that moulding sands with biodegradable materials selected as binders are not only less toxic but are also better suited to mechanical reclamation than moulding sands with phenol-furfuryl resin. The use of biodegradable materials as additives to typical synthetic resins can result in their decreased toxicity and improved ability to reclamation as well as in accelerated biodegradation of binding material leftovers of mechanical reclamation.

  1. Fixation of Selenium by Clay Minerals and Iron Oxides

    DEFF Research Database (Denmark)

    Hamdy, A. A.; Nielsen, Gunnar Gissel

    1977-01-01

    In studying Se fixation, soil components capable of retaining Se were investigated. The importance of Fe hydrous oxides in the fixation of Se was established. The clay minerals common to soils, such as kaolinite, montmorillonite and vermiculite, all exhibited Se fixation, but greater fixation...

  2. In Vivo Gait Analysis During Bone Transport.

    Science.gov (United States)

    Mora-Macías, J; Reina-Romo, E; Morgaz, J; Domínguez, J

    2015-09-01

    The load bearing characteristics of the intervened limb over time in vivo are important to know in distraction osteogenesis and bone healing for the characterization of the bone maturation process. Gait analyses were performed for a group of sheep in which bone transport was carried out. The ground reaction force was measured by means of a force platform, and the gait parameters (i.e., the peak, the mean vertical ground reaction force and the impulse) were calculated during the stance phase for each limb. The results showed that these gait parameters decreased in the intervened limb and interestingly increased in the other limbs due to the implantation of the fixator. Additionally, during the process, the gait parameters exponentially approached the values for healthy animals. Corresponding radiographies showed an increasing level of ossification in the callus. This study shows, as a preliminary approach to be confirmed with more experiments, that gait analysis could be used as an alternative method to control distraction osteogenesis or bone healing. For example, these analyses could determine the appropriate time to remove the fixator. Furthermore, gait analysis has advantages over other methods because it provides quantitative data and does not require instrumented fixators. PMID:25650097

  3. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  4. Antimicrobial activity of UMFix tissue fixative

    OpenAIRE

    Cleary, T J; Morales, A. R.; Nadji, M.; Nassiri, M.; Vincek, V.

    2005-01-01

    Aims: The aim of this study was to determine the antimicrobial effects of UMFix, an alcohol based tissue fixative, on various microorganisms. The UMFix solution was compared with 10% neutral buffered formalin.

  5. Triple fixation of Bacillus subtilis dormant spores.

    OpenAIRE

    Kozuka, S; Tochikubo, K

    1983-01-01

    A triple-fixation method with a sequential application of 5% glutaraldehyde, 1% osmium tetroxide, and 2% potassium permanganate gave superior preservation of the ultrastructure of Bacillus subtilis dormant spores with a thick spore coat.

  6. Review of 31 cases of anterior thoracolumbar fixation with the anterior thoracolumbar locking plate system.

    Science.gov (United States)

    Wilson, J A; Bowen, S; Branch, C L; Meredith, J W

    1999-07-15

    Anterior fixation devices for the thoracolumbar spine have gained wide acceptance as viable alternatives to long-segment posterior fixation in cases of thoracolumbar spine trauma. This review was undertaken to evaluate the safety and efficacy of the Synthes anterior thoracolumbar locking plate (ATLP) system. Over a 3-year period, 31 patients with unstable traumatic fractures of the thoracolumbar spine underwent corpectomy, placement of a structural bone graft, and anterior fixation in which the Synthes ATLP system was used. Long-term follow-up data were obtained in 29 patients. Two patients were lost to follow up, one at 4 months and the other at 1 year. In the remaining patients, the average length of follow up was 20 months. In all patients radiographic evidence of solid bone fusion was demonstrated on follow-up plain x-ray films, and there were no signs or symptoms of pseudarthrosis. No patient suffered neurological deterioration as a result of surgery, and there was relatively little morbidity associated with this plating system. To date, none of the patients in this study has developed any delayed complications related to the fixation device. In one patient, who had sustained a severe flexion injury, loosening of the anterior fixation device occurred, and the patient developed progressive kyphosis, which required a posterior stabilization procedure. These results appear slightly better than those obtained in published studies in which other anterior plating systems were used, indicating that this system is safe and effective in the treatment of unstable fractures of the thoracolumbar spine. PMID:16918232

  7. Tamponade following sternoclavicular dislocation surgical fixation.

    Science.gov (United States)

    Bensafi, H; Laffosse, J-M; Taam, S A; Molinier, F; Chaminade, B; Puget, J

    2010-05-01

    The authors report a case of posterior sternoclavicular dislocation surgically reduced and stabilized with tenodesis, according to the Burrows technique completed by temporary wire fixation. The patient presented postoperative pericardiac tamponade appearing progressively from brachiocephalic blood vessels bleeding. Emergency drainage was surgically placed associated with removal of the material, thus curing the patient. This complication, although exceptional, formally contraindicates the use of wire fixation in surgery of the sternoclavicular joint. PMID:20488152

  8. IRAT research work on nitrogen fixation

    International Nuclear Information System (INIS)

    The Institut de Recherches Agronomiques Tropicales et des Cultures Vivrieres (IRAT), in co-operation with the IAEA, has carried out research on groundnut and soybean in Senegal at the Institut Senegalais de Recherche Agricole (ISRA) in Bambey. The use of 15N to study dinitrogen fixation as affected by various agronomic factors is discussed. A model to determine the limiting factors in dinitrogen fixation in a given system is presented. (author)

  9. Pelvic fixation for neuromuscular scoliosis deformity correction

    OpenAIRE

    Dayer, Romain; Ouellet, Jean Albert; Saran, Neil

    2012-01-01

    Pelvic fixation is most frequently indicated in the pediatric population for the treatment of neuromuscular scoliosis with significant pelvic obliquity. Neuromuscular scoliosis surgery is associated with a high risk of complications, and this is further increased by extension of fusion to the sacrum. Numerous techniques have been described for pelvic fixation associated with a long spine fusion each with its own set of specific benefits and risks. This article reviews the contemporary surgica...

  10. Tips and Tricks in Mallet Fracture Fixation.

    Science.gov (United States)

    Chin, Yuin Cheng; Foo, Tun-Lin

    2016-10-01

    We describe three steps to aid fracture assessment and fixation in the extensor block pin technique for mallet fractures. The first step is the use of fluoroscopy in the initial assessment to determine indication for fixation. Next is the use of supplementary extension block pin to control larger dorsal fragments. The third technique described details the steps of open reduction of nascently malunited fractures. PMID:27595969

  11. Characterization of a biodegradable coralline hydroxyapatite/calcium carbonate composite and its clinical implementation

    International Nuclear Information System (INIS)

    A partially converted, biodegradable coralline hydroxyapatite/calcium carbonate (CHACC) composite comprising a coral calcium carbonate scaffold enveloped by a thin layer of hydroxyapatite was used in the present study. The CHACC was characterized using powder x-ray diffraction, scanning electron microscopy and energy dispersive x-ray spectroscopy. The ability of the CHACC to promote conductive osteogenesis was assessed in vitro using human mesenchymal stem cells (hMSCs) and in vivo using an immunodeficient mouse model. The clinical performance of CHACC as a bone substitute to fill voids caused by excision of bone tumours was also observed in 16 patients. The CHACC was found to consist of two overlapping layers both morphologically and chemically. Hydroxyapatite formed a thin layer of nanocrystals on the surface and a thick rough crystal layer of around 30 µm in thickness enveloping the rock-like core calcium carbonate exoskeletal architecture. hMSCs cultured on CHACC in osteogenic medium demonstrated significant osteogenic differentiation. After subcutaneous implantation of CHACC incorporating osteogenically differentiated hMSCs and an anti-resorptive agent, risedronate, into an immunodeficient mouse model, bone formation was observed on the surface of the implants. Clinical application of CHACC alone in 16 patients for bone augmentation after tumour removal showed that after implantation, visible callus formation was observed at one month and clinical bone healing achieved at four months. The majority of the implanted CHACC was degraded in 18–24 months. In conclusion, CHACC appears to be an excellent biodegradable bone graft material. It biointegrates with the host, is osteoconductive, biodegradable and can be an attractive alternative to autogenous grafts. (paper)

  12. Maxwellian Eye Fixation during Natural Scene Perception

    Science.gov (United States)

    Duchesne, Jean; Bouvier, Vincent; Guillemé, Julien; Coubard, Olivier A.

    2012-01-01

    When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF) of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell's law for each participant and for each scene condition (normal or scrambled). The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes. PMID:23226987

  13. Maxwellian Eye Fixation during Natural Scene Perception

    Directory of Open Access Journals (Sweden)

    Jean Duchesne

    2012-01-01

    Full Text Available When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell’s law for each participant and for each scene condition (normal or scrambled. The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes.

  14. Fixational eye movements predict visual sensitivity.

    Science.gov (United States)

    Scholes, Chris; McGraw, Paul V; Nyström, Marcus; Roach, Neil W

    2015-10-22

    During steady fixation, observers make small fixational saccades at a rate of around 1-2 per second. Presentation of a visual stimulus triggers a biphasic modulation in fixational saccade rate-an initial inhibition followed by a period of elevated rate and a subsequent return to baseline. Here we show that, during passive viewing, this rate signature is highly sensitive to small changes in stimulus contrast. By training a linear support vector machine to classify trials in which a stimulus is either present or absent, we directly compared the contrast sensitivity of fixational eye movements with individuals' psychophysical judgements. Classification accuracy closely matched psychophysical performance, and predicted individuals' threshold estimates with less bias and overall error than those obtained using specific features of the signature. Performance of the classifier was robust to changes in the training set (novel subjects and/or contrasts) and good prediction accuracy was obtained with a practicable number of trials. Our results indicate a tight coupling between the sensitivity of visual perceptual judgements and fixational eye control mechanisms. This raises the possibility that fixational saccades could provide a novel and objective means of estimating visual contrast sensitivity without the need for observers to make any explicit judgement. PMID:26468244

  15. Surgical Management of Charcot Deformity for the Foot and Ankle-Radiologic Outcome After Internal/External Fixation.

    Science.gov (United States)

    Ettinger, Sarah; Plaass, Christian; Claassen, Leif; Stukenborg-Colsman, Christina; Yao, Daiwei; Daniilidis, Kiriakos

    2016-01-01

    Charcot neuropathy (CN) is a severe joint disease that makes surgical planning very challenging, because it is combined with ankle instability, serious deformities, and recurrent ulceration. The aim of the present study was to examine the rate of bone fusion after external or internal fixation in patients with CN. We retrospectively examined 58 patients with CN who had undergone reconstruction of the ankle either with tibiotalocalcaneal or tibiocalcaneal arthrodesis. The mean age was 59.1 (range 26 to 81) years at surgery. Of the 58 patients, 38 were treated using intramedullary nail arthrodesis and 19 using an external fixator (1 patient received neither). At a mean follow-up period of 31.3 (range 12 to 57) months, limb salvage and bone fusion had been achieved in 94.83%. The mean time to bone fusion was 12 (range 6 to 18) months. Three patients (5.2%) required a more proximal amputation. All but these 3 patients gained independent mobilization in custom feet orthoses or off the shelf orthoses. Of the 58 patients in the present cohort, 56 (96.6%) would undergo surgery again. In conclusion, internal and external fixation both lead to promising results in the treatment of CN. Internal fixation should be preferred when no indications of ulcer or infection are present. PMID:26898396

  16. Combining of small fragment screws and large fragment plates for open reduction and internal fixation of periprosthetic humeral fractures

    Directory of Open Access Journals (Sweden)

    Dominik Seybold

    2011-01-01

    Full Text Available Operative treatment of periprosthetic humeral fractures in elderly patients with osteoporotic bone requires a stable fixations technique. The combination of 3.5 cortical screws with washers in a 4.5 Arbeitsgemeinschaft fόr Osteosynthesefragen, Limited-contact dynamic compression plate or Locking plate, allows a stable periprosthetic fixation with the small 3.5 screws and 4.5 screws above and below the prosthesis, respectively. This combination is a cost-effective technique to treat periprosthetic humeral fractures.

  17. Bone tumor

    Science.gov (United States)

    ... physical exam. Tests that may be done include: Alkaline phosphatase blood level Bone biopsy Bone scan Chest x- ... also affect the results of the following tests: Alkaline phosphatase isoenzyme Blood calcium level Parathyroid hormone Blood phosphorus ...

  18. Preparation and Compressive Strength of Calcium Phosphate Bone Cement Containing N, O-carboxymethyl Chitosan

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    N, O-carboxymethyl chitosan ( CMCTS ), a kind of biodegradable organic substance, was added to calcium phosphate bone cement (CPC) to produce a composite more similar in composition to human bone. The compressive strength of the new material was increased by 10 times compared with conventional CPC.

  19. INTRA MEDULLARY FIXATION OF SUB TROCHANTERIC FRACTURERS WITH LONG PROXIMAL FEMORAL NAIL & STAINLESS STEEL WIRE FIXATION: A STUDY

    Directory of Open Access Journals (Sweden)

    Sree Krishna

    2015-01-01

    Full Text Available INTRODUCTION: The objective of this study was to prospectively evaluate the clinical outcome of traumatic subtrochanteric fractures fixed with long proximal femoral nail (PFN & Stainless s te e l wire banding Fixation with particular emphasis on our experience of surgical techniques. Materials and Methods: We reviewed the results of 49 consecutive patients who had undergone intramedullary fixation specifically with a long PFN with S.S wire banding fixation for traumatic subtrochanteric fractures in our hospital during a 2 - year period from January 2013 to December 2014. The average age of the patients was 53 years. Clinical and radiographic analyses were performed when follow - up was made at 6 weeks, 12 weeks, 6 months, 1 year and 2 years. Results: All the 49 traumatic subtro chanteric fractures healed uneventfully except 1 case of delayed union. Walking and squatting ability was completely restored in every case at follow - up examination 6 months postoperatively. Among them, 32 fractures were successfully reduced with traction on a fracture table under fluoroscopy & cerclage wiring or bandage with S.S wire of various diameters (1.6, 1.8 etcthrough a small incision near the fragment to be fixed. The average operative time was 70 minutes (range, 45 to 120. Seventeen Seinsheimer type II fractures were left unlocked distally, and static distal interlocking with 1 bolt was carried out in the other 31 cases. No complications such as cutout or breakage of the implants were encountered. Conclusions: The objective of this study was to evaluate the clinical and radiological outcome of traumatic subtrochanteric fractures with trochanteric exten sion treated with long proximal femoral locking nail (PFNL & S.S wire. This study suggests that long PFN is a reliable implant for subtrochanteric fractures, leading to high rate of bone union and minimal soft tissue damage. Intramedullary fixation has bi ological and biomechanical advantages, but the operation

  20. UK DRAFFT - A randomised controlled trial of percutaneous fixation with kirschner wires versus volar locking-plate fixation in the treatment of adult patients with a dorsally displaced fracture of the distal radius

    Directory of Open Access Journals (Sweden)

    Brown Jaclyn

    2011-09-01

    Full Text Available Abstract Background Fractures of the distal radius are extremely common injuries in adults. However, the optimal management remains controversial. In general, fractures of the distal radius are treated non-operatively if the bone fragments can be held in anatomical alignment by a plaster cast or orthotic. However, if this is not possible, then operative fixation is required. There are several operative options but the two most common in the UK, are Kirschner-wire fixation (K-wires and volar plate fixation using fixed-angle screws (locking-plates. The primary aim of this trial is to determine if there is a difference in the Patient-Reported Wrist Evaluation one year following K-wire fixation versus locking-plate fixation for adult patients with a dorsally-displaced fracture of the distal radius. Methods/design All adult patients with an acute, dorsally-displaced fracture of the distal radius, requiring operative fixation are potentially eligible to take part in this study. A total of 390 consenting patients will be randomly allocated to either K-wire fixation or locking-plate fixation. The surgery will be performed in trauma units across the UK using the preferred technique of the treating surgeon. Data regarding wrist function, quality of life, complications and costs will be collected at six weeks and three, six and twelve months following the injury. The primary outcome measure will be wrist function with a parallel economic analysis. Discussion This pragmatic, multi-centre trial is due to deliver results in December 2013. Trial registration Current Controlled Trials ISRCTN31379280 UKCRN portfolio ID 8956

  1. Nitrogen fixation in trees - 1

    Energy Technology Data Exchange (ETDEWEB)

    Dobereiner, J.; Gauthier, D.L.; Diem, H.G.; Dommergues, Y.R.; Bonetti, R.; Oliveira, L.A.; Magalhaes, F.M.M.; Faria, S.M. de; Franco, A.A.; Menandro, M.S.

    1984-01-01

    Six papers are presented from the symposium. Dobereiner, J.; Nodulation and nitrogen fixation in leguminous trees, 83-90, (15 ref.), reviews studies on Brazilian species. Gauthier, D.L., Diem, H.G., Dommergues, Y.R., Tropical and subtropical actinorhizal plants, 119-136, (Refs. 50), reports on studies on Casuarinaceae. Bonetti, R., Oliveira, L.A., Magalhaes, F.M.M.; Rhizobium populations and occurrence of VA mycorrhizae in plantations of forest trees, 137-142, (Refs. 15), studies Amazonia stands of Cedrelinga catenaeformis, Calophyllum brasiliense, Dipteryx odorata, D. potiphylla, Carapa guianensis, Goupia glabra, Tabebuia serratifolia, Clarisia racemosa, Pithecellobium racemosum, Vouacapoua pallidior, Eperua bijuga, and Diplotropis species. Nodulation was observed in Cedrelinga catenaeformis and V. pallidior. Faria, S.M. de, Franco, A.A., Menandro, M.S., Jesus, R.M. de, Baitello, J.B.; Aguiar, O.T. de, Doebereiner, J; survey of nodulation in leguminous tree species native to southeastern Brazil, 143-153, (Refs. 7), reports on 119 species, with first reports of nodulation in the genera Bowdichia, Poecilanthe, Melanoxylon, Moldenhaurea (Moldenhawera), and Pseudosamanea. Gaiad, S., Carpanezzi, A.A.; Occurrence of Rhizobium in Leguminosae of silvicultural interest for south Brazil, 155-158, (Refs. 2). Nodulation is reported in Mimosa scabrella, Acacia mearnsii, A. longifolia various trinervis, Enterolobium contortisiliquum, and Erythrina falcata. Magalhaes, L.M.S., Blum, W.E.H., Nodulation and growth of Cedrelinga catanaeformis in experimental stands in the Manaus region - Amazonas, 159-164, (Refs. 5). Results indicate that C. catenaeformis can be used in degraded areas of very low soil fertility.

  2. Biodegradation kinetics at low concentrations (

    DEFF Research Database (Denmark)

    Toräng, Lars; Albrechtsen, Hans-Jørgen; Nyholm, Niels

    2000-01-01

    Aerobic biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in groundwater added sediment fines. At concentrations at or below 1 mu g/L of 2,4-D degradation kinetic was of true first order without significant growth of specific degraders and with half-life for mineralization in the...... order of 200 days. Higher concentrations of 2,4-D resulted in a grossly overestimate of the actual degradation rate for concentrations characteristic for Danish found in groundwater....

  3. Enhancing the mechanical integrity of the implant-bone interface with BoneWelding technology: determination of quasi-static interfacial strength and fatigue resistance.

    Science.gov (United States)

    Ferguson, Stephen J; Weber, Urs; von Rechenberg, Brigitte; Mayer, Joerg

    2006-04-01

    The BoneWelding technology is an innovative bonding method, which offers new alternatives in the treatment of fractures and other degenerative disorders of the musculoskeletal system. The BoneWelding process employs ultrasonic energy to liquefy a polymeric interface between orthopaedic implants and the host bone. Polymer penetrates the pores of the surrounding bone and, following a rapid solidification, forms a strong and uniform bond between implant and bone. Biomechanical testing was performed to determine the quasi-static push-out strength and fatigue performance of 3.5-mm-diameter polymeric dowels bonded to a bone surrogate material (Sawbones solid and cellular polyurethane foam) using the BoneWelding process. Fatigue tests were conducted over 100,000 cycles of 20-100 N loading. Mechanical test results were compared with those obtained with a comparably-sized, commercial metallic fracture fixation screw. Tests in surrogate bone material of varying density demonstrated significantly superior mechanical performance of the bonded dowels in comparison to conventional bone screws (p Ultrasonically inserted implants migrated, on average, less than 20 microm over, and interfacial stiffness remained constant the full duration of fatigue testing. With further refinement, the BoneWelding technology may offer a quicker, simpler, and more effective method for achieving strong fixation and primary stability for fracture fixation or other orthopaedic and dental implant applications. PMID:16211571

  4. Composite Scaffolds for Bone Tissue Engineering

    OpenAIRE

    Min Wang

    2006-01-01

    Biomaterial and scaffold development underpins the advancement of tissue engineering. Traditional scaffolds based on biodegradable polymers such as poly(lactic acid) and poly(lactic acid-co-glycolic acid) are weak and non-osteoconductive. For bone tissue engineering, polymer-based composite scaffolds containing bioceramics such as hydroxyapatite can be produced and used. The bioceramics can be either incorporated in the scaffolds as a dispersed secondary phase or form a thin coating on the po...

  5. Bioabsorbable fish scale for the internal fixation of fracture: a preliminary study.

    Science.gov (United States)

    Chou, Cheng-Hung; Chen, Yong-Guei; Lin, Chien-Chen; Lin, Shang-Ming; Yang, Kai-Chiang; Chang, Shih-Hsin

    2014-09-01

    Fish scales, which consist of type I collagen and hydroxyapatite (HA), were used to fabricate a bioabsorbable bone pin in this study. Fresh fish scales were decellularized and characterized to provide higher biocompatibility. The mechanical properties of fish scales were tested, and the microstructure of an acellular fish scale was examined. The growth curve of a myoblastic cell line (C2C12), which was cultured on the acellular fish scales, implied biocompatibility in vitro, and the morphology of the cells cultured on the scales was observed using scanning electron microscopy (SEM). A bone pin made of decellularized fish scales was used for the internal fixation of femur fractures in New Zealand rabbits. Periodic X-ray evaluations were obtained, and histologic examinations were performed postoperatively. The present results show good cell growth on decellularized fish scales, implying great biocompatibility in vitro. Using SEM, the cell morphology revealed great adhesion on a native, layered collagen structure. The Young's modulus was 332 ± 50.4 MPa and the tensile strength was 34.4 ± 6.9 MPa for the decellularized fish scales. Animal studies revealed that a fish-scale-derived bone pin improved the healing of bone fractures and degraded with time. After an 8-week implantation, the bone pin integrated with the adjacent tissue, and new extracellular matrix was synthesized around the implant. Our results proved that fish-scale-derived bone pins are a promising implant material for bone healing and clinical applications. PMID:25211643

  6. 半月板移植的固定法对胫股关节屈曲中韧带及骨骼的力学特性影响%EFFECTS OF THE FIXATION METHODS OF MENISCUS ALLOGRAFT ON THE MECHANICAL CHARACTERISTIC OF LIGAMENTS AND BONE IN TIBIOFEMORAL JOINT

    Institute of Scientific and Technical Information of China (English)

    郭云飞; 黄荣瑛; 张高龙

    2013-01-01

    基于正常膝关节4个屈曲角度(0°/25°/60°/80°)下的MRI图像数据,构建了正常以及内侧半月板移植术中双隧道固定和三隧道固定的胫股关节有限元模型,对屈曲角系列下的4种模型分别施加10N·m的内外旋扭矩进行有限元仿真,得到各模型在两种载荷作用下的应力及位移分布,通过从仿真结果中提取各韧带表面的最大拉应力、韧带内的张力及韧带的最大变形量以及股骨、胫骨最大等效应力进行对比分析,获得了内侧半月板移植的双隧道/三隧道固定方法对胫股关节屈曲中韧带及骨骼力学特性的影响.结果表明:同类异体半月板移植的两种固定方法均在一定程度上改善了半月板切除引起的韧带力学行为的异常情况,尤其以采用三隧道固定后的改善更为明显.与双隧道固定相比,三隧道固定使各屈曲角度下韧带表面最大拉应力的变化更为小些,且对各韧带内张力的大小的改变也更微小;虽然三隧道固定使两种载荷作用下韧带的平均变形量的变化更大一些,但4个屈曲角度下的平均变化百分比不超过10%.同类异体半月板移植的两种固定方法均在一定程度上影响股骨和胫骨应力分布,但采用三隧道固定后的影响相对于双隧道固定的小.综合而言,三隧道固定比双隧道固定更利于移植膝韧带力学性能的恢复和胫骨/股骨接近正常的骨骼应力分布.该文的研究结果能为同类异体半月板移植手术的临床实施和术后分析提供参考数据.%Based on MRI images of the normal human knee at four flexion angles(0°25°60°/80°), the finite element models of the normal tibiofemoral joint and two medial meniscus transplantation models (2-tunnel fixation and 3-tunnel fixation) were built in this paper. The internal and external rotation torque of 10N·m were applied to models for the finite element simulation and the stress and displacement

  7. Biodegradation and toxicological evaluation of lubricant oils

    Directory of Open Access Journals (Sweden)

    Ivo Shodji Tamada

    2012-12-01

    Full Text Available The aim of this work was to compare different toxicity levels of lubricant oils. The tests were performed using the earthworm (Eisenia andrei, arugula seeds (Eruca sativa and lettuce seeds (Lactuca sativa, with three types of contaminants (mineral lubricant oil, synthetic lubricant oil and used lubricant oil for various biodegradation periods in the soil. The toxicity tests indirectly measured the biodegradation of the contaminants. The samples were analyzed at t0, t60, t120 and t180 days of biodegradation. The used lubricant oil was proved very toxic in all the tests and even after biodegradation its toxicity was high. The mineral and synthetic oils were biodegraded efficiently in the soil although their toxicity did not disappear completely after 180 days.

  8. MRI analysis of the ISOBAR TTL internal fixation system for the dynamic fixation of intervertebral discs: a comparison with rigid internal fixation

    OpenAIRE

    Gao, Jun; Zhao, Weihua; Zhang, Xi; Nong, Luming; Zhou, Dong; Lv, Zhengxiang; Sheng, Yonghua; Wu, Xingbiao

    2014-01-01

    Objectives Using magnetic resonance imaging (MRI), we analyzed the efficacy of the posterior approach lumbar ISOBAR TTL internal fixation system for the dynamic fixation of intervertebral discs, with particular emphasis on its effects on degenerative intervertebral disc disease. Methods We retrospectively compared the MRIs of 54 patients who had previously undergone either rigid internal fixation of the lumbar spine or ISOBAR TTL dynamic fixation for the treatment of lumbar spondylolisthesis....

  9. BMP2 Genetically Engineered MSCs and EPCs Promote Vascularized Bone Regeneration in Rat Critical-Sized Calvarial Bone Defects

    OpenAIRE

    He, Xiaoning; Dziak, Rosemary; Yuan, Xue; Mao, Keya; Genco, Robert; Swihart, Mark; Sarkar, Debanjan; Li, Chunyi; Wang, Changdong; Lu, Li; Andreadis, Stelios; Yang, Shuying

    2013-01-01

    Current clinical therapies for critical-sized bone defects (CSBDs) remain far from ideal. Previous studies have demonstrated that engineering bone tissue using mesenchymal stem cells (MSCs) is feasible. However, this approach is not effective for CSBDs due to inadequate vascularization. In our previous study, we have developed an injectable and porous nano calcium sulfate/alginate (nCS/A) scaffold and demonstrated that nCS/A composition is biocompatible and has proper biodegradability for bon...

  10. Composites structures for bone tissue reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Neto, W.; Santos, João [Universidade Federal de São Carlos, Departament of Materials Engineering - Rd. Washington Luis, Km 235, 13565-905, São Carlos-SP (Brazil); Avérous, L.; Schlatter, G.; Bretas, Rosario, E-mail: bretas@ufscar.br [Université de Strasbourg, ECPM-LIPHT - 25 rue Becquerel, 67087, Strasbourg (France)

    2015-05-22

    The search for new biomaterials in the bone reconstitution field is growing continuously as humane life expectation and bone fractures increase. For this purpose, composite materials with biodegradable polymers and hydroxyapatite (HA) have been used. A composite material formed by a film, nanofibers and HA has been made. Both, the films and the non-woven mats of nanofibers were formed by nanocomposites made of butylene adipate-co-terephthalate (PBAT) and HA. The techniques used to produce the films and nanofibers were spin coating and electrospinning, respectively. The composite production and morphology were evaluated. The composite showed an adequate morphology and fibers size to be used as scaffold for cell growth.

  11. Composites structures for bone tissue reconstruction

    Science.gov (United States)

    Neto, W.; Santos, João.; Avérous, L.; Schlatter, G.; Bretas, Rosario.

    2015-05-01

    The search for new biomaterials in the bone reconstitution field is growing continuously as humane life expectation and bone fractures increase. For this purpose, composite materials with biodegradable polymers and hydroxyapatite (HA) have been used. A composite material formed by a film, nanofibers and HA has been made. Both, the films and the non-woven mats of nanofibers were formed by nanocomposites made of butylene adipate-co-terephthalate (PBAT) and HA. The techniques used to produce the films and nanofibers were spin coating and electrospinning, respectively. The composite production and morphology were evaluated. The composite showed an adequate morphology and fibers size to be used as scaffold for cell growth.

  12. Evaluation of four methods for cytomegalovirus antibody detection for use by a bone marrow transplantation service.

    OpenAIRE

    Leland, D S; Barth, K A; Cunningham, E B; Jansen, J; Tricot, G J; French, M L

    1989-01-01

    Four methods, latex agglutination, indirect fluorescent antibody, enzyme immunoassay, and complement fixation, were compared for cytomegalovirus antibody screening and for pre- and posttransplant determinations on bone marrow transplant recipients. Latex agglutination was most sensitive (98%) and specific (97%) for screening and pretransplant determinations and was quickest and easiest to perform. In posttransplant sera from allogeneic bone marrow transplant recipients, all methods except com...

  13. An injectable calcium phosphate cement for the local delivery of paclitaxel to bone

    NARCIS (Netherlands)

    Lopez-Heredia, M.A.; Kamphuis, G.J.; Thune, P.C.; Oner, F.C.; Jansen, J.A.; Walboomers, X.F.

    2011-01-01

    Bone metastases are usually treated by surgical removal, fixation and chemotherapeutic treatment. Bone cement is used to fill the resection voids. The aim of this study was to develop a local drug delivery system using a calcium phosphate cement (CPC) as carrier for chemotherapeutic agents. CPC cons

  14. Changes of blood circulation of the extremity after external fixation for tibia shaft defect: an experimental study

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To assess and compare two approaches, end to endcompression with lengthening (EECL) and segmental bone transport by lengthening (STBL), for long tubular bone defect and nonunion.Methods: Ten goats were used to establish the bone defect model of the mid-tibia. The bone defect ends were shortened step by step with a sulcated half-ring external fixator. Changes of the blood flow of the distal extremity were measured with pulse-Doppler monitor and angiography.Results: The blood flow in the distal extremity was not affected when bone defect was less than 15% of the original length. Blood circulatory disorder would appear in the distal extremity when bone defect ranged 15%-20% of the original length. The necrosis would appear in the extremity because of the blood circulatory obstacle when bone defect was more than 20% of the original length.Conclusions: EECL is an appropriate alternative of treatments if bone defect is less than 15%; while SBTL may be feasible if bone defect is over 20% of the original length. When bone defect ranges between 15% and 20%, EECL should be applied with great care on condition of keeping watch on the extremity circulation with pulse-Doppler monitor.

  15. Hollow-Bone-Graft Dynamic Hip Screw Can Fix and Promote Bone Union after Femoral Neck Fracture: an Experimental Research

    Directory of Open Access Journals (Sweden)

    Jia-zuo SHEN, Jian-fei YAO, Da-sheng LIN, Ke-jian LIAN, Zhen-qi DING, Bin LIN, Zhi-min GUO, Ming-hua ZHANG, Qiang LI, Lin LI, Peng QI

    2012-01-01

    Full Text Available Background: Delayed bone union, nonunion or osteonecrosis often occur after femoral neck fractures in young adults. Secondary bone healing requires strong internal fixation, intramedullary pressure reduction and early functional exercise.Objective: To compare bone healing of femoral neck fractures treated with hollow-bone-graft dynamic hip screws (Hb-DHS and standard dynamic hip screws (DHS in an animal model.Design: Testing of specifically designed fixation devices in a pig animal model.Interventions/Methods: We designed Hb-DHS and DHS devices appropriate to the femoral neck and head of experimental animals and used them in eight pigs (4-month-old, male or female, 30-40 kg/each. Under anesthesia, we induced medium neck type, Garden III type femoral neck fractures in each pig with fracture gaps of 0.5 mm and then fixed each left femur with Hb-DHS and each right femur with DHS. We assessed the animals radiographically and by postmortem visual appraisal of evidence of bone healing 8 and 16 weeks postoperatively.Results: There were significant differences in radiographic and general findings between the Hb-DHS and DHS groups at weeks 8 and 16 postoperatively. We found statistically significant differences between the Hb-DHS and DHS groups in bone healing scores, trabecular bone volume percentage and bone mineral density as assessed on plain radiographs and computed tomography images (P < 0.05. There were also significant differences between the Hb-DHS and DHS groups in postmortem visually assessed indicators of bone healing at both 8 and 16 weeks postoperatively.Conclusions: The Hb-DHS device promotes femoral neck bone union, stimulates trabecular bone formation, increases BMD and has advantages over DHS for internal fixation of femoral neck fractures. This animal experiment will contribute to developing optimal treatment for femoral neck fractures in young adults.

  16. Surface Accelerometer Fixation Method Affects Leg Soft Tissue Motion Following Heel Impacts

    Directory of Open Access Journals (Sweden)

    Jennifer M. Stefanczyk

    2013-10-01

    Full Text Available Surface-mounted accelerometers (SMA secured tightly to body segments with an elastic strap, are commonly used to quantify the impact response of bone.  However, the effect that this type of fixation has on segment soft tissue motion relative to bone has yet to be determined.  Heel impacts were collected from 20 participants using a human pendulum apparatus, with (strap and without (no strap a SMA attached to the proximal tibia.  Leg soft tissue motion was quantified using digital image analysis software which monitored positions of skin markers from a series of high speed photographs.  The strap was found to alter the natural physiological motion of the soft tissue, with significant displacement, velocity and sex differences occurring within the most proximal regions.  Future research should evaluate alternative methods for quantifying bone and soft tissue response to impact concurrently, to advance our understanding of impact-related injury mechanisms.

  17. Standard bone healing stages occur during delayed bone healing, albeit with a different temporal onset and spatial distribution of callus tissues

    OpenAIRE

    Peters, Anja; Schell, Hanna; Bail, Hermann J.; Hannemann, Marion; Schumann, Tanja; Duda, Georg N; Lienau, Jasmin

    2010-01-01

    Bone healing is considered as a recapitulation of a developmental program initiated at the time of injury. This study tested the hypothesis that in delayed bone healing the regular cascade of healing events, including remodeling of woven to lamellar bone, would be similar compared to standard healing, although the temporal onset would be delayed. A tibial osteotomy was performed in sheep and stabilized with a rotationally unstable fixator leading to delayed healing....

  18. A Case Report of Multiple Aneurysmal Bone Cysts

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Case Report A 30-year old male patient, admitted in our hospital for a fracture of the upper end of the left humerus in February, 2006, received treatment with curettage of the lesion in combination with an autologous bone graft from the right ilium plus internal fixation. A post-operative pathological examination indicated that there was a simple bone cyst in the area of the fracture, with a satisfactory postoperative recovery.

  19. Biodegradable Mg corrosion and osteoblast cell culture studies

    International Nuclear Information System (INIS)

    Magnesium (Mg) is a biodegradable metal that has significant potential advantages as an implant material. In this paper, corrosion and cell culture experiments were performed to evaluate the biocompatibility of Mg. The corrosion current and potential of a Mg disk were measured in different physiological solutions including deionized (DI) water, phosphate-buffered saline (PBS), and McCoy's 5A culture medium. The corrosion currents in the PBS and in the McCoy's 5A-5% FBS media were found to be higher than in DI water, which is expected because corrosion of Mg occurs faster in a chloride solution. Weight loss, open-circuit potential, and electrochemical impedance spectroscopy measurements were also performed. The Mg specimens were also characterized using an environmental scanning electron microscope and energy-dispersive X-ray analysis (EDAX). The X-ray analysis showed that in the cell culture media a passive interfacial layer containing oxygen, chloride, phosphate, and potassium formed on the samples. U2OS cells were then co-cultured with a Mg specimen for up to one week. Cytotoxicity results of magnesium using MTT assay and visual observation through cell staining were not significantly altered by the presence of the corroding Mg sample. Further, bone tissue formation study using von Kossa and alkaline phosphatase staining indicates that Mg may be suitable as a biodegradable implant material.

  20. Intimately coupling of photolysis accelerates nitrobenzene biodegradation, but sequential coupling slows biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lihui [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Zhang, Yongming, E-mail: zhym@shnu.edu.cn [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Bai, Qi; Yan, Ning; Xu, Hua [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Rittmann, Bruce E. [Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, Tempe, AZ 85287-5701 (United States)

    2015-04-28

    Highlights: • Intimately coupled UV photolysis accelerated nitrobenzene biodegradation. • NB biodegradation was slowed by accumulation of nitrophenol. • Oxalic acid was a key product of UV photolysis. • Oxalic acid accelerated biodegradation of nitrobenzene and nitrophenol by a co-substrate effect. • Intimate coupling of UV and biodegradation accentuated the benefits of oxalic acid. - Abstract: Photo(cata)lysis coupled with biodegradation is superior to photo(cata)lysis or biodegradation alone for removal of recalcitrant organic compounds. The two steps can be carried out sequentially or simultaneously via intimate coupling. We studied nitrobenzene (NB) removal and mineralization to evaluate why intimate coupling of photolysis with biodegradation was superior to sequential coupling. Employing an internal circulation baffled biofilm reactor, we compared direct biodegradation (B), biodegradation after photolysis (P + B), simultaneous photolysis and biodegradation (P&B), and biodegradation with nitrophenol (NP) and oxalic acid (OA) added individually and simultaneously (B + NP, B + OA, and B + NP + OA); NP and OA were NB’s main UV-photolysis products. Compared with B, the biodegradation rate P + B was lower by 13–29%, but intimately coupling (P&B) had a removal rate that was 10–13% higher; mineralization showed similar trends. B + OA gave results similar to P&B, B + NP gave results similar to P + B, and B + OA + NP gave results between P + B and P&B, depending on the amount of OA and NP added. The photolysis product OA accelerated NB biodegradation through a co-substrate effect, but NP was inhibitory. Although decreasing the UV photolysis time could minimize the inhibition impact of NP in P + B, P&B gave the fastest removal of NB by accentuating the co-substrate effect of OA.

  1. Intimately coupling of photolysis accelerates nitrobenzene biodegradation, but sequential coupling slows biodegradation

    International Nuclear Information System (INIS)

    Highlights: • Intimately coupled UV photolysis accelerated nitrobenzene biodegradation. • NB biodegradation was slowed by accumulation of nitrophenol. • Oxalic acid was a key product of UV photolysis. • Oxalic acid accelerated biodegradation of nitrobenzene and nitrophenol by a co-substrate effect. • Intimate coupling of UV and biodegradation accentuated the benefits of oxalic acid. - Abstract: Photo(cata)lysis coupled with biodegradation is superior to photo(cata)lysis or biodegradation alone for removal of recalcitrant organic compounds. The two steps can be carried out sequentially or simultaneously via intimate coupling. We studied nitrobenzene (NB) removal and mineralization to evaluate why intimate coupling of photolysis with biodegradation was superior to sequential coupling. Employing an internal circulation baffled biofilm reactor, we compared direct biodegradation (B), biodegradation after photolysis (P + B), simultaneous photolysis and biodegradation (P&B), and biodegradation with nitrophenol (NP) and oxalic acid (OA) added individually and simultaneously (B + NP, B + OA, and B + NP + OA); NP and OA were NB’s main UV-photolysis products. Compared with B, the biodegradation rate P + B was lower by 13–29%, but intimately coupling (P&B) had a removal rate that was 10–13% higher; mineralization showed similar trends. B + OA gave results similar to P&B, B + NP gave results similar to P + B, and B + OA + NP gave results between P + B and P&B, depending on the amount of OA and NP added. The photolysis product OA accelerated NB biodegradation through a co-substrate effect, but NP was inhibitory. Although decreasing the UV photolysis time could minimize the inhibition impact of NP in P + B, P&B gave the fastest removal of NB by accentuating the co-substrate effect of OA

  2. 椎弓根螺钉内固定材料置入并植骨融合后路矫正治疗重度僵硬性青少年特发性脊柱侧凸20例%Posterior correction using pedicle screw fixation combined with bone grafting and fusion for treatment of severe and rigid adolescent idiopathic scoliosis in 20 cases

    Institute of Scientific and Technical Information of China (English)

    臧危平; 刘祖德; 李展春; 冯宇; 张磊

    2008-01-01

    主弯平均Cobb角从术前的82°(75o~ 92o)矫正到31°(22°~37°),平均矫正率为62%.③双肩高度差及住院时间:术后脊柱侧位片均显示患者胸腰椎基本恢复正常后凸及前凸,平均双肩高度差为7.5 mm(0~11 mm),患者住院日为8~11 d, 平均9 d.④随访结果:所有患者均获术后4年随访,所有侧凸主弯矫正角度未发生丢失,固定节段全部融合,无断钉、断棒发生.结论:单纯后路椎弓根螺钉内固定材料置入并植骨融合术能有效治疗主弯在75o~92o,柔韧性≥ 20%的重度僵硬性青少年特发性脊柱侧凸.%BACKGROUND: Traditional anterior release followed by posterior correction and fusion is frequently used to treat severe and rigid adolescent idiopathic scoliosis, which is considered as Cobb angle of the major curve > 65° and flexibility < 34.5%; however, there are a great majority of complications. Whether isolated posterior correction using pedicle screw fixation combining with bone grafting and fusion may provide better effects on severe and rigid adolescent idiopathic scoliosis needs to be further studied.OBJECTIVE: To evaluate isolated posterior correction using pedicle screw fixation combining with bone grafting and fusion for the treatment of severe and rigid adolescent idiopathic scoliosis. DESIGN: Case analysis.SETTING: Department of Orthopaedics, Renji Hospital, Medical College of Shanghai Jiao Tong University.PARTICIPANTS: Twenty patients with severe and rigid adolescent idiopathic scoliosis, including 8 males and 12 females, were selected from Department of Orthopaedics, Renji Hospital, Medical College of Shanghai Jiaotong University from June 1999 to August 2005. They were 12-18 years old, and the mean age was 14.6 years. All patients were finally diagnosed as X-ray of whole spine. According to King-Moe criteria, patients were classified into type Ⅰ(n =4), type Ⅱ(n =6), type Ⅲ (n =5), type Ⅳ(n =3) and type Ⅴ(n =2). Before surgery, mean Cobb angle of the major curve was 82

  3. Chemical and physical basics of routine formaldehyde fixation

    Directory of Open Access Journals (Sweden)

    Rooban Thavarajah

    2012-01-01

    Full Text Available Formaldehyde is the widely employed fixative that has been studied for decades. The chemistry of fixation has been studied widely since the early 20 th century. However, very few studies have been focused on the actual physics/chemistry aspect of process of this fixation. This article attempts to explain the chemistry of formaldehyde fixation and also to study the physical aspects involved in the fixation. The factors involved in the fixation process are discussed using well documented mathematical and physical formulae. The deeper understanding of these factors will enable pathologist to optimize the factors and use them in their favor.

  4. Chemical and physical basics of routine formaldehyde fixation.

    Science.gov (United States)

    Thavarajah, Rooban; Mudimbaimannar, Vidya Kazhiyur; Elizabeth, Joshua; Rao, Umadevi Krishnamohan; Ranganathan, Kannan

    2012-09-01

    Formaldehyde is the widely employed fixative that has been studied for decades. The chemistry of fixation has been studied widely since the early 20(th) century. However, very few studies have been focused on the actual physics/chemistry aspect of process of this fixation. This article attempts to explain the chemistry of formaldehyde fixation and also to study the physical aspects involved in the fixation. The factors involved in the fixation process are discussed using well documented mathematical and physical formulae. The deeper understanding of these factors will enable pathologist to optimize the factors and use them in their favor. PMID:23248474

  5. Breast specimen shrinkage following formalin fixation

    Directory of Open Access Journals (Sweden)

    Horn CL

    2014-02-01

    Full Text Available Christopher L Horn, Christopher Naugler Department of Pathology and Laboratory Medicine, University of Calgary, and Calgary Laboratory Services, Calgary, AB, Canada Abstract: Accurate measurement of primary breast tumors and subsequent surgical margin assessment is critical for pathology reporting and resulting patient therapy. Anecdotal observations from pathology laboratory staff indicate possible shrinkage of breast cancer specimens due to the formalin fixation process. As a result, we conducted a prospective study to investigate the possible shrinkage effects of formalin fixation on breast cancer specimens. The results revealed no significant changes in tumor size, but there were significant changes in the distance to all surgical resection margins from the unfixed to fixed state. This shrinkage effect could interfere with the accuracy of determining distance to margin assessment and tumor-free margin assessment. Thus, changes in these measurements due to the formalin fixation process have the potential to alter treatment options for the patient. Keywords: breast margins, formalin, shrinkage, cancer

  6. Transarticular screw fixation using neuronavigation: Technique

    Directory of Open Access Journals (Sweden)

    Dwarakanath Srinivas

    2007-01-01

    Full Text Available Background: Transarticular screw placement needs highly accurate imaging. We assess the efficacy and accuracy of C1-C2 transarticular screw fixation using neuronavigation and also cast a technical note on the procedure. Materials and Methods: This study included a total of nine patients who underwent transarticular screw fixation using the neuronavigation system. A total of 15 screws were placed. All patients underwent postoperative CT scan with 3-Dimensional (3-D reconstruction to check for the accuracy of implantation. Results: One patient had encroachment of the transverse foramen but there was no vertebral artery injury. There were no clinical complications or adverse sequelae. Conclusion: Neuronavigation is extremely helpful in C1-C2 transarticular screw fixation and gives excellent accuracy.

  7. Combined Percutaneous Iliosacral Screw Fixation With Sacroplasty Using Resorbable Calcium Phosphate Cement for Osteoporotic Pelvic Fractures Requiring Surgery.

    Science.gov (United States)

    Collinge, Cory A; Crist, Brett D

    2016-06-01

    Osteoporotic sacral fractures, including acute and chronic insufficiency fractures, are increasing in frequency and present a number of management problem. Many of these patients are treated nonoperatively with relative immobility (eg, bedrest, wheelchair, or weight-bearing restrictions) and analgesics, which likely make the osteoporotic component worse. Surgery in this patient population may be desirable in some cases with the goals of improving mobility, relieving pain, and healing in an aligned position while minimizing deformity progression. However, internal fixation of the osteoporotic pelvis can be difficult. Large unicortical lag screws are the workhorse of posterior pelvic fixation, and yet fixation in cancellous bone corridors of an osteoporotic sacrum seems unlikely to achieve optimal fixation. As a result, the operative management and clinical results of these difficult injuries may not be uniformly successful. The authors present a technique for treating osteoporotic patients with a sacral fracture when operative treatment is indicated using percutaneous screw fixation combined with screw augmentation using a resorbable calcium phosphate bone substitute or "cement." The guide wire for a 7.3-mm or other large cannulated lag screw is fully inserted along the desired bony sacral corridor as is standard. The lag screw is then inserted over the wire to the depth where cement is desired. The guide wire is removed, and the aqueous calcium phosphate is injected through the screw's cannulation. For acute fractures, cement was applied to the areas distant to the fracture; whereas in insufficiency fractures, the cement was inserted along most of the screw path. The guide wire then can be reinserted and the lag screw fully inserted. The rationale for using these 2 modalities is their synergistic effect: the cannulated screw provides typical screw fixation and also a conduit for cement application. The cement augments the lag screw's purchase in osteoporotic bone

  8. Preparation and Characterization of an Advanced Medical Device for Bone Regeneration

    OpenAIRE

    Dorati, Rossella; Colonna, Claudia; Genta, Ida; Bruni, Giovanna; Visai, Livia; Conti, Bice

    2013-01-01

    Tridimensional scaffolds can promote bone regeneration as a framework supporting the migration of cells from the surrounding tissue into the damaged tissue and as delivery systems for the controlled or prolonged release of cells, genes, and growth factors. The goal of the work was to obtain an advanced medical device for bone regeneration through coating a decellularized and deproteinized bone matrix of bovine origin with a biodegradable, biocompatible polymer, to improve the cell engraftment...

  9. Bone uptake of rare earths and transuranic elements

    International Nuclear Information System (INIS)

    In the first part of this paper formation conditions of citric complexes of rare earths and transuranic elements are presented. In the second part, role of binding proteins in plasma is emphasized. Finally biological behaviour of the injected elements is evidenced. A general mechanism for fixation of these elements in bone and liver is proposed

  10. The effect on implant fixation of soaking tricalcium phosphate granules in bisphosphonate

    DEFF Research Database (Denmark)

    Jakobsen, Thomas; Baas, Jørgen; Bechtold, Joan E;

    2012-01-01

    biomechanical implant fixation and osseointegration of experimental implant grafted with β-TCP granules (Conduit) could be improved by soaking the β-TCP granules in bisphosphonate (zoledronate). In 10 dogs, a pair of titanium coated implants surrounded by a 2.5 mm gap was inserted into the proximal part of each...... tibia. The gap was grafted with β-TCP granules either soaked with zoledronate or saline. At 12 weeks, the implants were evaluated with biomechanical push-out test and histomorphometrical analysis. We found that bisphosphonate increased one of the three biomechanical parameters, but found no difference...... in the amount of new bone or β-TCP granules between the two treatment groups. This study indicates that local treatment of β-TCP granules with zoledronate not only has the potential to increase implant fixation but also calls for further experimental research in order to optimize the dose of zoledronate....

  11. A preliminary study of bending stiffness alteration in shape changing nitinol plates for fracture fixation.

    Science.gov (United States)

    Olender, Gavin; Pfeifer, Ronny; Müller, Christian W; Gösling, Thomas; Barcikowski, Stephan; Hurschler, Christof

    2011-05-01

    Nitinol is a promising biomaterial based on its remarkable shape changing capacity, biocompatibility, and resilient mechanical properties. Until now, very limited applications have been tested for the use of Nitinol plates for fracture fixation in orthopaedics. Newly designed fracture-fixation plates are tested by four-point bending to examine a change in equivalent bending stiffness before and after shape transformation. The goal of stiffness alterable bone plates is to optimize the healing process during osteosynthesis in situ that is customized in time of onset, percent change as well as being performed non-invasively for the patient. The equivalent bending stiffness in plates of varying thicknesses changed before and after shape transformation in the range of 24-73% (p values inertia. PMID:21286815

  12. External fixation of complex femoral shaft fractures

    OpenAIRE

    Zlowodzki, M; Prakash, J. S.; Aggarwal, N. K.

    2006-01-01

    Conversion of temporary external fixation to an intramedullary nail within the first 2 weeks after a femoral shaft fracture is standard practice. However, due to financial constraints, in large parts of the world external fixation of femoral shaft fractures is often the definitive treatment. Out of 60 fractures, 47 were followed-up for a minimum period of 39 weeks. The average follow-up time was 75 weeks. Fourteen fractures were closed, and 33 open. Forty-four fractures united at an average o...

  13. Biodegradable Metals From Concept to Applications

    CERN Document Server

    Hermawan, Hendra

    2012-01-01

    This book in the emerging research field of biomaterials covers biodegradable metals for biomedical applications. The book contains two main parts where each of them consists of three chapters. The first part introduces the readers to the field of metallic biomaterials, exposes the state of the art of biodegradable metals, and reveals its application for cardiovascular implants. It includes some fundamental aspects to give basic understanding on metals for further review on the degradable ones is covered in chapter one. The second chapter introduces the concept of biodegradable metals, it's st

  14. Biodegradation of surfactant bearing wastes

    International Nuclear Information System (INIS)

    In nuclear industry, during decontamination of protective wears and contaminated materials, detergents are employed to bring down the level of radioactive contamination within safe limits. However, the surfactant present in these wastes interferes in the chemical treatment process, reducing the decontamination factor. Biodegradation is an efficient and ecologically safe method for surfactant removal. A surfactant degrading culture was isolated and inoculated separately into simulated effluents containing 1% yeast extract and 5-100 ppm sodium lauryl sulphate (SLS) and 1% yeast extract and 5-100 ppm of commercial detergent respectively. The growth of the bacterial culture and the degradation characteristics of the surfactant in the above effluents were monitored under both dynamic and static conditions. (author). 6 refs., 6 figs., 1 tab

  15. New perspectives in plastic biodegradation.

    Science.gov (United States)

    Sivan, Alex

    2011-06-01

    During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. PMID:21356588

  16. Engineered biosynthesis of biodegradable polymers.

    Science.gov (United States)

    Jambunathan, Pooja; Zhang, Kechun

    2016-08-01

    Advances in science and technology have resulted in the rapid development of biobased plastics and the major drivers for this expansion are rising environmental concerns of plastic pollution and the depletion of fossil-fuels. This paper presents a broad view on the recent developments of three promising biobased plastics, polylactic acid (PLA), polyhydroxyalkanoate (PHA) and polybutylene succinate (PBS), well known for their biodegradability. The article discusses the natural and recombinant host organisms used for fermentative production of monomers, alternative carbon feedstocks that have been used to lower production cost, different metabolic engineering strategies used to improve product titers, various fermentation technologies employed to increase productivities and finally, the different downstream processes used for recovery and purification of the monomers and polymers. PMID:27260524

  17. Use of functional gene arrays for elucidating in situ biodegradation

    Directory of Open Access Journals (Sweden)

    JoyD.Van Nostrand

    2012-09-01

    Full Text Available Microarrays have revolutionized the study of microbiology by providing a high-throughput method for examining thousands of genes with a single test and overcome the limitations of many culture-independent approaches. Functional gene arrays (FGA probe a wide range of genes involved in a variety of functions of interest to microbial ecology (e.g., carbon degradation, N-fixation, metal resistance from many different microorganisms, cultured and uncultured. The most comprehensive FGA to date is the GeoChip array, which targets tens of thousands of genes involved in the geochemical cycling of carbon, nitrogen, phosphorus, and sulphur, metal resistance and reduction, energy processing, antibiotic resistance and contaminant degradation as well as phylogenetic information (gyrB. Since the development of GeoChips, many studies have been performed using this FGA and have shown it to be a powerful tool for rapid, sensitive and specific examination of microbial communities in a high-throughput manner. As such, the GeoChip is well-suited for linking geochemical processes with microbial community function and structure. This technology has been used successfully to examine microbial communities before, during and after in situ bioremediation at a variety of contaminated sites. These studies have expanded our understanding of biodegradation and bioremediation processes and the associated microorganisms and environmental conditions responsible. This review provides an overview of FGA development with a focus on the GeoChip and highlights specific GeoChip studies involving in situ bioremediation.

  18. Chitosan Composites for Bone Tissue Engineering—An Overview

    Directory of Open Access Journals (Sweden)

    Jayachandran Venkatesan

    2010-08-01

    Full Text Available Bone contains considerable amounts of minerals and proteins. Hydroxyapatite [Ca10(PO46(OH2] is one of the most stable forms of calcium phosphate and it occurs in bones as major component (60 to 65%, along with other materials including collagen, chondroitin sulfate, keratin sulfate and lipids. In recent years, significant progress has been made in organ transplantation, surgical reconstruction and the use of artificial protheses to treat the loss or failure of an organ or bone tissue. Chitosan has played a major role in bone tissue engineering over the last two decades, being a natural polymer obtained from chitin, which forms a major component of crustacean exoskeleton. In recent years, considerable attention has been given to chitosan composite materials and their applications in the field of bone tissue engineering due to its minimal foreign body reactions, an intrinsic antibacterial nature, biocompatibility, biodegradability, and the ability to be molded into various geometries and forms such as porous structures, suitable for cell ingrowth and osteoconduction. The composite of chitosan including hydroxyapatite is very popular because of the biodegradability and biocompatibility in nature. Recently, grafted chitosan natural polymer with carbon nanotubes has been incorporated to increase the mechanical strength of these composites. Chitosan composites are thus emerging as potential materials for artificial bone and bone regeneration in tissue engineering. Herein, the preparation, mechanical properties, chemical interactions and in vitro activity of chitosan composites for bone tissue engineering will be discussed.

  19. Biodegradation of halogenated organic compounds.

    Science.gov (United States)

    Chaudhry, G R; Chapalamadugu, S

    1991-03-01

    In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant

  20. No effect of platelet-rich plasma with frozen or processed bone allograft around noncemented implants

    DEFF Research Database (Denmark)

    Jensen, T B; Rahbek, O; Overgaard, S; Søballe, Kjeld

    2005-01-01

    We compared processed morselized bone allograft with fresh-frozen bone graft around noncemented titanium implants. Also, the influence of platelet-rich plasma (PRP) in combination with bone allograft was evaluated. Analysis was based on implant fixation and histomorphometry. PRP was prepared by...... isolating the buffy coat from autologous blood samples. Bone allograft was used fresh-frozen or processed by defatting, freeze drying, and irradiation. Cylindrical hydroxyapatite-coated titanium implants were inserted bilaterally in the femoral condyles of eight dogs. Each implant was surrounded by a 2.5-mm...... bone allograft processing. Even though the level of platelet in PRP was 7.7 times that found in whole blood, we found no improvement of bone formation or implant fixation by adding PRP....