WorldWideScience

Sample records for bone fixation devices

  1. Fixation Release and the Bone Bandaid: A New Bone Fixation Device Paradigm

    Directory of Open Access Journals (Sweden)

    Narges Shayesteh Moghaddam

    2017-01-01

    Full Text Available The current gold standard of care for mandibular segmental defeat reconstruction is the use of Ti-6Al-4V immobilization hardware and fibular double barrel graft. This method is often successful immediately at restoring mandible function, however the highly stiff fixation hardware causes stress shielding of the grafted bone and stress concentration in the fixation device over time which can lead to fixation device failure and revision surgery. The purpose of reconstructive surgery could be to create normal stress trajectories in the mandible following engraftment. We investigate the use of a two stage mechanism which separates the immobilization/healing and regenerative phases of mandibular segmental defect treatment. The device includes the use of a very stiff, Ti-6Al-4V, releasable mechanism which assures bone healing. Therefore it could be released once the reconstructed boney tissue and any of its ligamentous attachments have completely healed. Underneath the released Ti-6Al-4V plate would be a pre-loaded nitinol (NiTi wire-frame apparatus that facilitates the normal stress-strain trajectory through the engrafted bone after the graft is healed in place and the Ti-6Al-4V fixation device has been released. Due to the use of NiTi wires forming a netting that connects vascularized bone and possibly bone chips, bone grafts are also more likely to be incorporate rather than to resorb. We first evaluated a healthy adult mandible during normal mastication to obtain the normal stress-strain distribution. Then, we developed the finite element (FE model of the mandibular reconstruction (in the M1-3 region with the proposed fixation device during the healing (locked state and post-healing (released state periods. To recreate normal stress trajectory in the reconstructed mandible, we applied the Response Surface Methodology (RMS to optimize the Bone Bandaid geometry (i.e., wire diameters and location. The results demonstrate that the proposed mechanism

  2. Mechanical design optimization of bioabsorbable fixation devices for bone fractures.

    Science.gov (United States)

    Lovald, Scott T; Khraishi, Tariq; Wagner, Jon; Baack, Bret

    2009-03-01

    Bioabsorbable bone plates can eliminate the necessity for a permanent implant when used to fixate fractures of the human mandible. They are currently not in widespread use because of the low strength of the materials and the requisite large volume of the resulting bone plate. The aim of the current study was to discover a minimally invasive bioabsorbable bone plate design that can provide the same mechanical stability as a standard titanium bone plate. A finite element model of a mandible with a fracture in the body region is subjected to bite loads that are common to patients postsurgery. The model is used first to determine benchmark stress and strain values for a titanium plate. These values are then set as the limits within which the bioabsorbable bone plate must comply. The model is then modified to consider a bone plate made of the polymer poly-L/DL-lactide 70/30. An optimization routine is run to determine the smallest volume of bioabsorbable bone plate that can perform and a titanium bone plate when fixating fractures of this considered type. Two design parameters are varied for the bone plate design during the optimization analysis. The analysis determined that a strut style poly-L-lactide-co-DL-lactide plate of 690 mm2 can provide as much mechanical stability as a similar titanium design structure of 172 mm2. The model has determined a bioabsorbable bone plate design that is as strong as a titanium plate when fixating fractures of the load-bearing mandible. This is an intriguing outcome, considering that the polymer material has only 6% of the stiffness of titanium.

  3. 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.

  4. MODELING OF BONE FRAGMENTS FIXATION WITH AN EXTERNAL FIXATION DEVICE FOR BILATERAL ROTATION UNSTABLE PELVIC INJURIES B TYPE ACCORDING TO AO/ASIF CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    V. G. Vinogradov

    2014-01-01

    Full Text Available Objective: to determine the stability of bone fragments fixation with an external fixation device in the simulation of bilateral partly unstable pelvic injuries of B type according to AO/ASIF classification and to identify the role of different fixation elements in the stability of fixation. Material and methods: the study was performed on the finite element model of a system “an external fixation device - pelvis” developed for a software package MSCNastran. Formation of a fracture of pubic and ischial pelvic bones was accomplished by means of rupture in the finite element network and decrease of elasticity modulus in the ilio-sacral joint on both sides up to 35 mm at the site of a fracture. Loads were carried on top of the body of the first sacral vertebra with a force of 500H.The second area of application of the load was from the bottom-up on the acetabular roof with a force of 250H. In this study the effect of different elements of an external fixation device on the stiffness of bone fragments fixation was evaluated. Symmetrical elements were removed both separately and together. As a result, the stiffness of a system decreased and the displacement at the fracture site increased. Conclusion: in a model of partly stable pelvic injuries accompanied by general rotation instability in the horizontal and sagittal planes to 35 mm, an external fixation device provided high stability of bone fragments (to 3 mm due to introduction of bone rods in the iliac wings with the obligatory introduction of the rod in the vertical branches of pubic bones and strengthening the anterior lower bar between the subsystems. What is more, installing the anterior upper bar or introduction of bone rods in the bodies of iliac bone are not necessary.

  5. Effect of hydroxyapatite concentration on high-modulus composite for biodegradable bone-fixation devices.

    Science.gov (United States)

    Heimbach, Bryant; Grassie, Kevin; Shaw, Montgomery T; Olson, James R; Wei, Mei

    2016-06-14

    There are over 3 million bone fractures in the United States annually; over 30% of which require internal mechanical fixation devices to aid in the healing process. The current standard material used is a metal plate that is implanted onto the bone. However, metal fixation devices have many disadvantages, namely stress shielding and metal ion leaching. This study aims to fix these problems of metal implants by making a completely biodegradable material that will have a high modulus and exhibit great toughness. To accomplish this, long-fiber poly-l-lactic acid (PLLA) was utilized in combination with a matrix composed of polycaprolactone (PCL) and hydroxyapatite (HA) nano-rods. Through single fibril tensile tests, it was found that the PLLA fibers have a Young's modulus of 8.09 GPa. Synthesized HA nanorods have dimensions in the nanometer range with an aspect ratio over 6. By dip coating PLLA fibers in a suspension of PCL and HA and hot pressing the resulting coated fibers, dense fiber-reinforced samples were made having a flexural modulus up to 9.2 GPa and a flexural strength up to 187 MPa. The flexural modulus of cortical bone ranges from 7 to 25 GPa, so the modulus of the composite material falls into the range of bone. The typical flextural strength of bone is 130 MPa, and the samples here greatly exceed that with a strength of 187 MPa. After mechanical testing to failure the samples retained their shape, showing toughness with no catastrophic failure, indicating the possibility for use as a fixation material. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016.

  6. 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.

  7. In vitro and in vivo evaluation of a polylactic acid-bioactive glass composite for bone fixation devices.

    Science.gov (United States)

    Vergnol, Gwenaelle; Ginsac, Nathalie; Rivory, Pascaline; Meille, Sylvain; Chenal, Jean-Marc; Balvay, Sandra; Chevalier, Jérôme; Hartmann, Daniel J

    2016-01-01

    Poly(lactic acid) is nowadays among the most used bioabsorbable materials for medical devices. To promote bone growth on the material surface and increase the degradation rate of the polymer, research is currently focused on organic-inorganic composites by adding a bioactive mineral to the polymer matrix. The purpose of this study was to investigate the ability of a poly(L,DL-lactide)-Bioglass® (P(L,DL)LA-Bioglass(®) 45S5) composite to be used as a bone fixation device. In vitro cell viability testing of P(l,dl)LA based composites containing different amounts of Bioglass(®) 45S5 particles was investigated. According to the degradation rate of the P(L,DL)LA matrix and the cytocompatibility experiments, the composite with 30 wt % of Bioglass® particles seemed to be the best candidate for further investigation. To study its behavior after immersion in simulated physiological conditions, the degradation of the composite was analyzed by measuring its weight loss and mechanical properties and by proceeding with X-ray tomography. We demonstrated that the presence of the bioactive glass significantly accelerated the in vitro degradation of the polymer. A preliminary in vivo investigation on rabbits shows that the addition of 30 wt % of Bioglass(®) in the P(L,DL)LA matrix seems to trigger bone osseointegration especially during the first month of implantation. This composite has thus strong potential interest for health applications.

  8. 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...

  9. 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...

  10. Design and Optimization of Resorbable Silk Internal Fixation Devices

    Science.gov (United States)

    Haas, Dylan S.

    Limitations of current material options for internal fracture fixation devices have resulted in a large gap between user needs and hardware function. Metal systems offer robust mechanical strength and ease of implantation but require secondary surgery for removal and/or result in long-term complications (infection, palpability, sensitivity, etc.). Current resorbable devices eliminate the need for second surgery and long-term complications but are still associated with negative host response as well as limited functionality and more difficult implantation. There is a definitive need for orthopedic hardware that is mechanically capable of immediate fracture stabilization and fracture fixation during healing, can safely biodegrade while allowing complete bone remodeling, can be resterilized for reuse, and is easily implantable (self-tapping). Previous work investigated the use of silk protein to produce resorbable orthopedic hardware for non- load bearing fracture fixation. In this study, silk orthopedic hardware was further investigated and optimized in order to better understand the ability of silk as a fracture fixation system and more closely meet the unfulfilled market needs. Solvent-based and aqueous-based silk processing formulations were cross-linked with methanol to induce beta sheet structure, dried, autoclaved and then machined to the desired device/geometry. Silk hardware was evaluated for dry, hydrated and fatigued (cyclic) mechanical properties, in vitro degradation, resterilization, functionalization with osteoinductive molecules and implantation technique for fracture fixation. Mechanical strength showed minor improvements from previous results, but remains comparable to current resorbable fixation systems with the advantages of self-tapping ability for ease of implantation, full degradation in 10 months, ability to be resterilized and reused, and ability to release molecules for osteoinudction. In vivo assessment confirmed biocompatibility, showed

  11. The influence on the contact condition and initial fixation stability of the main design parameters of a self-expansion type anterior cruciate ligament fixation device

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Dae [Jeonju University, Jeonju (Korea, Republic of); Oh, Chae Youn; Kim, Cheol Sang [Chonbuk National University, Jeonju (Korea, Republic of)

    2008-12-15

    This paper proposes a self-expansion type anterior cruciate ligament fixation device. The proposed fixation device provides graft fixation force by maintaining contact with the bone tunnel. Since the device maintains contact with the bone tunnel by the force that expands by the self-driven elastic force of the device, the main design parameters that determine the performance of this device are the ring thickness and expansion angle. This paper develops the three-dimensional finite element models of the fixation device and bone. By simulation with the developed finite element model, this paper studies the influence of the main design parameters of the device on the maximum stress around the ring when grasping the fixation device. Through the analysis of the stress on the bone tunnel wall when the fixation device comes in contact with the bone tunnel, this paper shows the influence of the main design parameters of the fixation device on the contact condition. In addition, through the analysis of the migration that occur upon application of the pull-out force, this paper studies the influence of the main design parameters on the initial fixation stability of the fixation device

  12. 骨外固定器在胫腓骨骨折中的应用及护理体会%The Application of External Bone Fixation Device in Tibia and Fibulac Fractures & Nursing Experience

    Institute of Scientific and Technical Information of China (English)

    唐红波; 陈克; 刘莉莉

    2012-01-01

    Objective:discuss the nursing experience when external bone fixation device is applied in tibia and fibulae fractures. Methods:select 58 people who suffered from tibia and fibulae fractures and were treated by external bone fixation device to summarize and analyse methods of treatment for fracture and humanistic nursing measures.Results:it took 7.8 months on average for 58 suffers of tibia and fibulae fractures to unite fractures. Among which, bone union was accomplished by 57 cases, while one wasn't healed.Conclusion:in terms of the treatment for tibia and fibulae fractures, external bone fixation device has been widely applied. Positive and effective measures shall be taken to facilitate the bone healing process and functional recovery of limbs so as to avoid the occurrence of complications.%目的:探讨在胫腓骨骨折中应用骨外固定器的护理体会.方法:选取58例使用骨外固定器治疗的胫腓骨骨折患者,对骨折治疗方法及人性化护理措施进行归纳和分析.结果:58例胫腓骨骨折患者的骨折平均愈合时间为7.8个月,其中,骨性愈合57例,未愈合1例.结论:在胫腓骨骨折的治疗中,骨外固定器已广泛应用,应当采取积极有效的护理措施,以促进骨折的愈合及肢体的功能恢复,防止并发症的发生.

  13. Novel anterior cruciate ligament graft fixation device reduces slippage.

    Science.gov (United States)

    Lopez, Mandi J; Borne, Allen; Monroe, W Todd; Bommala, Prakash; Kelly, Laura; Zhang, Nan

    2013-01-01

    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 confirm that initial graft slippage is lower with GG versus BP extracortical hamstring graft tibial fixation. In addition, postoperative recovery and joint stability are more consistent with the GG. This information supports the GG as an alternative to extracortical tibial hamstring graft fixation that has procedural advantages over current implants and reduces graft failure from slippage.

  14. Machining of a bioactive nanocomposite orthopedic fixation device.

    Science.gov (United States)

    Sparnell, Amie; Aniket; El-Ghannam, Ahmed

    2012-08-01

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

  15. Analysis of Bone Fixation Methods in Digital Replantation

    Science.gov (United States)

    Lee, Seung Woo; Kim, Jin Soo; Roh, Si Young; Lee, Kyung Jin

    2017-01-01

    Background Adequate fixation of replanted digits is essential not only for short-term healing but for long-term function. Various bony fixation methods using Kirschner (K-) and intraosseous wire are available in replantation. We examined clinical and radiographic outcomes of fixation methods on bone union after digital replantation. Methods A single institutional retrospective review identified 992 patients who had undergone 1,247 successful replantations between July 2009 and September 2015. Exclusion criteria included amputations of the distal phalanx, comminuted fractures, and intra-articular fractures. Patients were classified according to 5 categories of fixation methods: single K-wire, double longitudinal K-wires, cross K-wires, wire with, and wire without K-wire support. Bone union was evaluated by 5-month postoperative X-ray and fixation outcomes were compared across the 5 groups. Results The exclusion criteria were applied, and 88 patients with 103 replanted digits remained for analysis. Single K-wire fixation was used in 40 digits, double longitudinal K-wires in 30, and cross fixation in 14. Wire with and without K-wire support was required in 15 and 4 digits. Nonunion was observed in 32 digits (31.1%), of which 13 required additional operations such as bone graft or corrective osteotomy. The highest percent of nonunion was observed after cross fixation (35.7%) and the lowest after wire alone (25.0%). Conclusions In this study, contrary to general knowledge, we found that single K-wire fixation was not associated with poorer outcomes. Successful bone union outcomes may be achieved by careful selection of bone fixation methods. This study provides useful information for planning bone fixation in digital replantation. PMID:28194348

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

    DEFF Research Database (Denmark)

    Babiker, Hassan

    2013-01-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many...... the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking...... 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...

  17. 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

  18. 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.

  19. Injectable calcium phosphate cement for bone repair and implant fixation.

    NARCIS (Netherlands)

    Jansen, J.; Ooms, E.M.; Verdonschot, N.J.J.; Wolke, J.G.C.

    2005-01-01

    The studies as described are aimed at determining the efficacy of newly developed calcium phosphate cement when this material is used as a bone defect filler or gap filler around metal implants. An overview is provided about bone graft substitutes and methods of metal implant fixation.

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

    Science.gov (United States)

    Babiker, Hassan

    2013-07-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking skeletal bones. The osteoconductive properties of the composite might be improved by adding bone marrow aspirate (BMA), which can be harvested during surgery. Other alternatives to bone graft are demineralised bone matrix (DBM) and human cancellous bone (CB). DBM is prepared by acid extraction of human 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/Collagen composite alone and in combination with BMA on the early fixation of porous coated titanium implants. In addition, the study compares also the effect of autograft with the gold standard allograft. By using a sheep model, the implants were inserted in the trabecular bone of femoral condyles. The test biomaterials were placed in a well defined peri-implant gap. After the observation period, the bone-implant specimens were harvested and evaluated mechanically by a destructive push

  1. 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

  2. Bioreactor activated graft material for early implant fixation in bone

    DEFF Research Database (Denmark)

    Snoek Henriksen, Susan; Ding, Ming; Overgaard, Søren

    2011-01-01

    Introduction The combined incubation of a composite scaffold with bone marrow stromal cells in a perfusion bioreactor could make up a novel hybrid graft material with optimal properties for early fixation of implant to bone. The aim of this study was to create a bioreactor activated graft (BAG......) material, which could induce early implant fixation similar to that of allograft. Two porous scaffold materials incubated with cells in a perfusion bioreactor were tested in this study. Methods and Materials Two groups of 8 skeletally mature female sheep were anaesthetized before aspiration of bone marrow...... 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...

  3. Modeling and simulation of physical performance of a external unilateral mechatronic orthopaedic fixator - bone system.

    Science.gov (United States)

    Lesniewska, A; Choromanski, W; Deszczynski, J; Dobrzynski, G

    2006-01-01

    Restricted element study of the fracture healing by external fixation device was investigated. The analyses were performed under an axial and variable loaded boundary conditions. The effect of different fracture size and different distance between bone and the external fixator device on the stress distribution was investigated. The results show that stresses in the external fixator device are highest at the beginning of the fracture healing process, and are gradually decreasing with the time of the treatment. The analyses were carried out using the commercial package CATIA P3 V5R11. This allowed to build a three-dimensional model more similar to the geometrical architecture of the long bone as well as of the external fixator. Three-dimensional restricted element model also allowed a collection of more realistic results. However, the accuracy of the results depends not only on the quality of the model geometry but also on the material properties assigned to the model components. It also depends on the accuracy in the simulation of the finite element model and the optimized mesh generation.

  4. Observations concerning different patterns of bone healing using the Point Contact Fixator (PC-Fix) as a new technique for fracture fixation.

    Science.gov (United States)

    Hofer, H P; Wildburger, R; Szyszkowitz, R

    2001-09-01

    The recent trend in all surgical disciplines has been the development of techniques in minimally invasive surgery and the optimal maintenance of the blood supply to the bone fragments during osteosynthesis. Currently, the Point Contact Fixator (PC-Fix) has been introduced as a new implant for the stabilization of forearm bones. This plate-like splint and screw fixation system, which actually acts as an internal fixator, is characterized by minimized isolated contacts to the bone and proven angular stability of the monocortically locked screws. By using the PC-Fix, a further reduction of damage to the blood supply to the bone is achieved. Since 1994, 38 patients have been treated with this new device; we have reviewed the radiographs of 52 consolidated forearm fractures/osteotomies in accordance with the patterns of bone healing associated with the different methods of implant application according to the fracture type. In the groups in which traditionally precise reduction, interfragmentary compression and stable fixation was achieved (N=31), we found in 71% an absence of periosteal callus (direct bone healing). In the groups in which compression and adaptation were combined, or even main fragments adapted without compression, with wedges remaining unreduced in soft tissue connection (N=21), we found a visible external callus in 81% (indirect healing) (P = 0.002). Indirect healing after internal fixation is no longer regarded as a disturbance to healing, but is a goal in itself. The appearance of callus is a welcome sign indicating a prompt and positive reaction in the course of bone union which will lead to progressive fracture immobilization. When using the PC-Fix in a "biological way", callus formation and solid union take place earlier than in conventional plating. The new internal fixator offers substantial technical and mechanical advantages in fracture treatment. Therefore, it is an ideal implant to satisfy the requirements of modern biological

  5. Ergotropic effect of bone cement on pedicle screw fixation in treatment of osteoporotic thoracolumbar fracture

    Directory of Open Access Journals (Sweden)

    Da LIU

    2017-02-01

    Full Text Available Objective To evaluate the ergotropic effect of bone cement on pedicle screw fixation in treatment of osteopo¬rotic thoracolumbar fracture. Methods Fifty-three patients with osteoporotic thoracolumbar fracture, admitted from Jun. 2013 to Dec. 2014, were included for treatment by augmentation of pedicle screw fixation with bone cement. All patients underwent pre-operative examination of bone mineral density with T-score ≤-2.5 and augmentation of pedicle screw fixation with injection of 1.5 ml bone cement in adjacent to fractured vertebra. All patients were treated with anti-osteoporosis therapy pre- and post-operation, ob¬served and recorded with basic conditions and complications. At pre-operation, one-week post-operation and last follow-up, pain vi¬sual analogue scale (VAS and neurological function score (ASIA of all patients were recorded, and the compression rats of anterior and posterior edge of fractured vertebra, and compression rats of spinal canal and Cobb angel of all patients were measured. Results All the 53 patients were successfully undergone operation in about 90-140 min with blood loss of about 150-350 ml. No spinal cord or nerve injury, dural tear and obvious leakage of bone cement and screw loosening occurred during operation. All patients were followed up for 12 to 36 months and the neurological function obviously recovered contrasted with pre-operation. X-ray and CT examination at last follow-up showed good fractures healing, good position and non-loosening of internal fixation device and non-leakage of bone cement. At one week post-operation and last follow-up, VAS, compression rats of anterior edge and posterior edge of fractured vertebra, compression rats of spinal canal and Cobb angel were significantly lower than those at pre-operation (P0.05. Conclusions Augmentation of pedicle screw fixation with bone cement can effectively strengthen the initial stability of pedicle screw in osteo¬porosis, restore the

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

    Science.gov (United States)

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

    2012-07-26

    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 biomechanical issues such as considerable bone loss around the stem and peri-prosthetic bone fractures are present. To overcome these limiting issues a new concept of the direct intramedullary fixation was developed. We hypothesize that the new design will reduce the peri-prosthetic bone failure risk and adverse bone remodeling by restoring the natural load transfer in the femur. Generic CT-based finite element models of an intact femur and amputated bones implanted with 3 analyzed implants were created and loaded with a normal walking and a forward fall load. The strain adaptive bone remodeling theory was used to predict long-term bone changes around the implants and the periprosthetic bone failure risk was evaluated by the von Mises stress criterion. The results show that the new design provides close to physiological distribution of stresses in the bone and lower bone failure risk for the normal walking as compared to the OPRA and the ISP implants. The bone remodeling simulations did not reveal any overall bone loss around the new design, as opposed to the OPRA and the ISP implants, which induce considerable bone loss in the distal end of the femur. This positive outcome shows that the presented concept has a potential to considerably improve safety of the rehabilitation with the direct fixation implants.

  7. 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.

  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. 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.

  10. 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.

  11. Surgical treatment of zygomatic bone fracture using two points fixation versus three point fixation-a randomised prospective clinical trial

    Directory of Open Access Journals (Sweden)

    Rana Majeed

    2012-04-01

    Full Text Available Abstract Background The zygoma plays an important role in the facial contour for both cosmetic and functional reasons; therefore zygomatic bone injuries should be properly diagnosed and adequately treated. Comparison of various surgical approaches and their complications can only be done objectively using outcome measurements which in turn require protocol management and long-term follow up. The preference for open reduction and internal fixation of zygomatic fractures at three points has continued to grow in response to observations of inadequate results from two point and one point fixation techniques. The objectives of this study were to compare the efficacy of zygomatic bone after treatment with ORIF using 2 point fixation and ORIF using 3 point fixation and compare the outcome of two procedures. Methods 100 patients were randomly divided equally into two groups. In group A, 50 patients were treated by ORIF using two point fixation by miniplates and in group B, 50 patients were treated by ORIF using three point fixation by miniplates. They were evaluated for their complications during and after surgery with their advantages and disadvantages and the difference between the two groups was observed. Results A total of 100 fractures were sustained. We found that postoperative complication like decreased malar height and vertical dystopia was more common in those patients who were treated by two point fixation than those who were treated with three point fixation. Conclusions Based on this study open reduction and internal fixation using three point fixation by miniplates is the best available method for the treatment zygomatic bone fractures.

  12. Assessment of activated porous granules on implant fixation and early bone formation in sheep

    Directory of Open Access Journals (Sweden)

    Ming Ding

    2016-04-01

    Conclusion: In conclusion, despite nice bone formation and implant fixation in all groups, bioreactor activated graft material did not convincingly induce early implant fixation similar to allograft, and neither bioreactor nor by adding BMA credited additional benefit for bone formation in this model.

  13. Suboccipital neuropathy after bone conduction device placement

    NARCIS (Netherlands)

    Faber, H.T.; Ru, J.A. de

    2013-01-01

    OBJECTIVE: To describe the clinical characteristics of a 70-year-old female with occipital neuropathy following bone conduction device surgery. DESCRIPTION: A 65-year-old woman underwent bone conduction device placement surgery on the left temporal bone. Postoperatively she progressively developed c

  14. 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.

  15. Negative pressure wound therapy and external fixation device: a simple way to seal the dressing.

    Science.gov (United States)

    Bulla, Antonio; Farace, Francesco; Uzel, André-Pierre; Casoli, Vincent

    2014-07-01

    Negative pressure therapy is widely applied to treat lower limb trauma. However, sealing a negative pressure dressing in the presence of an external fixation device may be difficult and time consuming. Therefore, screws, pins, wires, etc, may preclude the vacuum, preventing the plastic drape to perfectly adhere to the foam. To maintain the vacuum, we tried to prevent air leaking around the screws putting bone wax at the junction between the pins and the plastic drape. This solution, in our hands, avoids air leakage and helps maintain vacuum in a fast and inexpensive way.

  16. 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

    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...... 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/Collagen...... and histomorphometry between autograft and allograft groups. The implants in both the HA/Collagen and HA/Collagen-BMA groups were mostly surrounded by fibrous tissue. Thus, mechanical testing of these samples was impossible. The histomorphometry results showed significantly more new bone and bone ongrowth...

  17. Calcium phosphate cement augmentation of cancellous bone screws can compensate for the absence of cortical fixation.

    Science.gov (United States)

    Stadelmann, Vincent A; Bretton, Elise; Terrier, Alexandre; Procter, Philip; Pioletti, Dominique P

    2010-11-16

    An obvious means to improve the fixation of a cancellous bone screw is to augment the surrounding bone with cement. Previous studies have shown that bone augmentation with Calcium Phosphate (CaP) cement significantly improves screw fixation. Nevertheless, quantitative data about the optimal distribution of CaP cement is not available. The present study aims to show the effect of cement distribution on the screw fixation strength for various cortical thicknesses and to determine the conditions at which cement augmentation can compensate for the absence of cortical fixation in osteoporotic bone. In this study, artificial bone materials were used to mimic osteoporotic cancellous bone and cortical bone of varying thickness. These bone constructs were used to test the fixation strength of cancellous bone screws in different cortical thicknesses and different cement augmentation depths. The cement distribution was measured with microCT. The maximum pullout force was measured experimentally. The microCT analysis revealed a pseudo-conic shape distribution of the cement around the screws. While the maximum pullout strength of the screws in the artificial bone only was 30±7N, it could increase up to approximately 1000N under optimal conditions. Cement augmentation significantly increased pullout force in all cases. The effect of cortical thickness on pullout force was reduced with increased cement augmentation depth. Indeed, cement augmentation without cortical fixation increased pullout forces over that of screws without cement augmentation but with cortical fixation. Since cement augmentation significantly increased pullout force in all cases, we conclude that the loss of cortical fixation can be compensated by cement augmentation.

  18. Periosteal augmentation of allograft bone and its effect on implant fixation - an experimental study on 12 dogs()

    DEFF Research Database (Denmark)

    Barckman, Jeppe; Baas, Jorgen; Sørensen, Mette;

    2013-01-01

    Periosteum provides essential cellular and biological components necessary for fracture healing and bone repair. We hypothesized that augmenting allograft bone by adding fragmented autologous periosteum would improve fixation of grafted implants.......Periosteum provides essential cellular and biological components necessary for fracture healing and bone repair. We hypothesized that augmenting allograft bone by adding fragmented autologous periosteum would improve fixation of grafted implants....

  19. A biomechanical study on fixation stability with twin hook or lag screw in artificial cancellous bone.

    Science.gov (United States)

    Olsson, O; Tanner, K E; Ceder, L; Ryd, L

    2002-01-01

    The twin hook has been developed as an alternative to the conventional lag screw to be combined with a barrelled side-plate in the treatment of trochanteric hip fractures. With two oppositely directed apical hooks introduced into the subchondral bone of the femoral head, the twin hook provides different stabilising properties to the lag screw. The femoral head purchase of the twin hook and the lag screw were compared in a biomechanical study using artificial cancellous bone, and responses to axial and torsional loading was determined. A distinct yield point in load and torque was noted for the lag screw, representing failure of the laminas supporting the threads. For the twin hook, gradual increase of load and torque occurred during impaction of the bone supporting the hooks. The peak loads and torques were higher for the lag screw, but were similar for both devices after 8 mm deformation. The stiffness was higher for the lag screw, but in counter-clockwise rotation the stiffness for the lag screw was negligible. The twin hook appeared to provide fixation stability comparable to that offered by the lag screw, but with conceivable advantages in terms of a deformation response involving bone impaction and gradually increasing stability.

  20. Novel intramedullary-fixation technique for long bone fragility fractures using bioresorbable materials.

    Directory of Open Access Journals (Sweden)

    Takanobu Nishizuka

    Full Text Available Almost all of the currently available fracture fixation devices for metaphyseal fragility fractures are made of hard metals, which carry a high risk of implant-related complications such as implant cutout in severely osteoporotic patients. We developed a novel fracture fixation technique (intramedullary-fixation with biodegradable materials; IM-BM for severely weakened long bones using three different non-metallic biomaterials, a poly(l-lactide (PLLA woven tube, a nonwoven polyhydroxyalkanoates (PHA fiber mat, and an injectable calcium phosphate cement (CPC. The purpose of this work was to evaluate the feasibility of IM-BM with mechanical testing as well as with an animal experiment. To perform mechanical testing, we fixed two longitudinal acrylic pipes with four different methods, and used them for a three-point bending test (N = 5. The three-point bending test revealed that the average fracture energy for the IM-BM group (PLLA + CPC + PHA was 3 times greater than that of PLLA + CPC group, and 60 to 200 times greater than that of CPC + PHA group and CPC group. Using an osteoporotic rabbit distal femur incomplete fracture model, sixteen rabbits were randomly allocated into four experimental groups (IM-BM group, PLLA + CPC group, CPC group, Kirschner wire (K-wire group. No rabbit in the IM-BM group suffered fracture displacement even under full weight bearing. In contrast, two rabbits in the PLLA + CPC group, three rabbits in the CPC group, and three rabbits in the K-wire group suffered fracture displacement within the first postoperative week. The present work demonstrated that IM-BM was strong enough to reinforce and stabilize incomplete fractures with both mechanical testing and an animal experiment even in the distal thigh, where bone is exposed to the highest bending and torsional stresses in the body. IM-BM can be one treatment option for those with severe osteoporosis.

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

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    Yun-Gang Luo

    2015-01-01

    Full Text Available 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 ® 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; 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.

  2. 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

    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...... of the Biomedical Laboratories, University of Southern Denmark, Odense. The observation period was 5 weeks. The sheeps were euthanized and both of femurs were harvested and sectioned in two parts by using a water-cooled diamond band saw. Specimens for mechanical testing were always taken from the most superficial...

  3. Development of a fixation device for robot assisted fracture reduction of femoral shaft fractures: a biomechanical study.

    Science.gov (United States)

    Weber-Spickschen, T S; Oszwald, M; Westphal, R; Krettek, C; Wahl, F; Gosling, T

    2010-01-01

    Robot assisted fracture reduction of femoral shaft fractures provides precise alignment while reducing the amount of intraoperative imaging. The connection between the robot and the fracture fragment should allow conventional intramedullary nailing, be minimally invasive and provide interim fracture stability. In our study we tested three different reduction tools: a conventional External Fixator, a Reposition-Plate and a Three-Point-Device with two variations (a 40 degrees and a 90 degrees version). We measured relative movements between the tools and the bone fragments in all translation and rotation planes. The Three-Point-Device 90 degrees showed the smallest average relative displacement and was the only device able to withstand the maximum applied load of 70 Nm without failure of any bone fragment. The Three-Point-Device 90 degrees complies with all the stipulated requirements and is a suitable interface for robot assisted fracture reduction of femoral shaft fractures.

  4. A novel internal fixator device for peripheral nerve regeneration.

    Science.gov (United States)

    Chuang, Ting-Hsien; Wilson, Robin E; Love, James M; Fisher, John P; Shah, Sameer B

    2013-06-01

    Recovery from peripheral nerve damage, especially for a transected nerve, is rarely complete, resulting in impaired motor function, sensory loss, and chronic pain with inappropriate autonomic responses that seriously impair quality of life. In consequence, strategies for enhancing peripheral nerve repair are of high clinical importance. Tension is a key determinant of neuronal growth and function. In vitro and in vivo experiments have shown that moderate levels of imposed tension (strain) can encourage axonal outgrowth; however, few strategies of peripheral nerve repair emphasize the mechanical environment of the injured nerve. Toward the development of more effective nerve regeneration strategies, we demonstrate the design, fabrication, and implementation of a novel, modular nerve-lengthening device, which allows the imposition of moderate tensile loads in parallel with existing scaffold-based tissue engineering strategies for nerve repair. This concept would enable nerve regeneration in two superposed regimes of nerve extension--traditional extension through axonal outgrowth into a scaffold and extension in intact regions of the proximal nerve, such as that occurring during growth or limb-lengthening. Self-sizing silicone nerve cuffs were fabricated to grip nerve stumps without slippage, and nerves were deformed by actuating a telescoping internal fixator. Poly(lactic co-glycolic) acid (PLGA) constructs mounted on the telescoping rods were apposed to the nerve stumps to guide axonal outgrowth. Neuronal cells were exposed to PLGA using direct contact and extract methods, and they exhibited no signs of cytotoxic effects in terms of cell morphology and viability. We confirmed the feasibility of implanting and actuating our device within a sciatic nerve gap and observed axonal outgrowth following device implantation. The successful fabrication and implementation of our device provides a novel method for examining mechanical influences on nerve regeneration.

  5. Surgical treatment of zygomatic bone fracture using two points fixation versus three point fixation-a randomised prospective clinical trial

    OpenAIRE

    2012-01-01

    Abstract Background The zygoma plays an important role in the facial contour for both cosmetic and functional reasons; therefore zygomatic bone injuries should be properly diagnosed and adequately treated. Comparison of various surgical approaches and their complications can only be done objectively using outcome measurements which in turn require protocol management and long-term follow up. The preference for open reduction and internal fixation of zygomatic fractures at three points has con...

  6. Femoral stiffness after osteosynthesis of a subcapital osteotomy in osteoporotic bone: an in-vitro comparison of nine fixation methods.

    Science.gov (United States)

    Hernefalk, L; Messner, K

    1995-01-01

    Restitution of normal bone mechanics after osteosynthesis of a proximal femoral fracture in the elderly is assumed to be a prerequisite for optimal healing. To find the most appropriate fixation device for this purpose, the stiffness of 79 cadaver femora from donors with a history of osteoporosis was measured during axial loading before and after a subcapital osteotomy stabilized with one of nine different osteosynthesis devices. Only an osteotomy stabilized with an experimental device consisting of 2 von Bahr screws (Ericsson AB, Göteborg, Sweden) supported by acrylic cement gave similar mean values as the intact femur. A femur stabilized with the Deyerle device (Biomet, Bridge End, Wales, U.K.), with cannulated screws type Uppsala (Olmed AB, Uppsala, Sweden), or with von Bahr screws had an approximately 20-30% lower stiffness than tested intact. However, these devices provided a higher femoral stiffness than the hook-pin technique type LiH (Söderström AB, Gothenburg, Sweden), cannulated screws (Smith & Nephew, Memphis, TN, U.S.A.), a sliding screw plate (Smith & Nephew), a compression screw with variable length (Biomet), or an experimental screw providing expansion and compression. Despite attempted compression of the osteotomy by some of the devices, all of the commercially available devices resulted in a decrease of femoral stiffness after fixation, which may adversely influence the healing of femoral neck fractures in the elderly. Only a combination of screws and bone cement resulted in normal femoral stiffness, probably because of better device anchorage in the osteoporotic cancellous bone. However, this combination might have the potential risk of vascular damage.

  7. 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.

  8. 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 either...... in each of the 8 treatment groups (total 64 implants in 32 dogs). The observation period was 4 weeks after revision. Outcome measures are based on histomorphometry and mechanical pushout properties. The revision setting was always inferior to its primary counterpart. Bone graft improved the revision...

  9. An application of principal component analysis to the clavicle and clavicle fixation devices

    Directory of Open Access Journals (Sweden)

    Fitzpatrick David

    2010-03-01

    Full Text Available Abstract Background Principal component analysis (PCA enables the building of statistical shape models of bones and joints. This has been used in conjunction with computer assisted surgery in the past. However, PCA of the clavicle has not been performed. Using PCA, we present a novel method that examines the major modes of size and three-dimensional shape variation in male and female clavicles and suggests a method of grouping the clavicle into size and shape categories. Materials and methods Twenty-one high-resolution computerized tomography scans of the clavicle were reconstructed and analyzed using a specifically developed statistical software package. After performing statistical shape analysis, PCA was applied to study the factors that account for anatomical variation. Results The first principal component representing size accounted for 70.5 percent of anatomical variation. The addition of a further three principal components accounted for almost 87 percent. Using statistical shape analysis, clavicles in males have a greater lateral depth and are longer, wider and thicker than in females. However, the sternal angle in females is larger than in males. PCA confirmed these differences between genders but also noted that men exhibit greater variance and classified clavicles into five morphological groups. Discussion And Conclusions This unique approach is the first that standardizes a clavicular orientation. It provides information that is useful to both, the biomedical engineer and clinician. Other applications include implant design with regard to modifying current or designing future clavicle fixation devices. Our findings support the need for further development of clavicle fixation devices and the questioning of whether gender-specific devices are necessary.

  10. Modulation of fixation stiffness from flexible to stiff in a rat model of bone healing.

    Science.gov (United States)

    Bartnikowski, Nicole; Claes, Lutz E; Koval, Lidia; Glatt, Vaida; Bindl, Ronny; Steck, Roland; Ignatius, Anita; Schuetz, Michael A; Epari, Devakara R

    2016-11-14

    Background and purpose - Constant fixator stiffness for the duration of healing may not provide suitable mechanical conditions for all stages of bone repair. We therefore investigated the influence of stiffening fixation on callus stiffness and morphology in a rat diaphyseal osteotomy model to determine whether healing time was shortened and callus stiffness increased through modulation of fixation from flexible to stiff. Material and methods - An external unilateral fixator was applied to the osteotomized femur and stiffened by decreasing the offset of the inner fixator bar at 3, 7, 14, and 21 days after operation. After 5 weeks, the rats were killed and healing was evaluated with mechanical, histological, and microcomputed tomography methods. Constant fixation stiffness control groups with either stiff or flexible fixation were included for comparison. Results - The callus stiffness of the stiff group and all 4 experimental groups was greater than in the flexible group. The callus of the flexible group was larger but contained a higher proportion of unmineralized tissue and cartilage. The stiff and modulated groups (3, 7, 14, and 21 days) all showed bony bridging at 5 weeks, as well as signs of callus remodeling. Stiffening fixation at 7 and 14 days after osteotomy produced the highest degree of callus bridging. Bone mineral density in the fracture gap was highest in animals in which the fixation was stiffened after 14 days. Interpretation - The predicted benefit of a large robust callus formed through early flexible fixation could not be shown, but the benefits of stabilizing a flexible construct to achieve timely healing were demonstrated at all time points.

  11. A Technique of Superficial Medial Collateral Ligament Reconstruction Using an Adjustable-Loop Suspensory Fixation Device.

    Science.gov (United States)

    Deo, Shaneel; Getgood, Alan

    2015-06-01

    This report describes superficial medial collateral ligament reconstruction of the knee using a novel method of graft fixation with the ACL Tightrope RT (Arthrex, Naples, FL). After tibial fixation with either a standard interference screw or staple, femoral fixation of the semitendinosus tendon is performed with the adjustable-loop suspensory fixation device, which allows for both initial graft tensioning and re-tensioning after cyclical knee range of motion. This provides the ability for the graft to accommodate for resultant soft-tissue creep and stress relaxation, thereby allowing for optimal soft-tissue tension and reduction in laxity at the end of the procedure.

  12. 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

    2016-01-01

    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...... 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...... (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...

  13. Timing of long bone fracture fixation in severe traumatic brain injury.

    Science.gov (United States)

    Jamjoom, Bakur A; Jamjoom, Abdulhakim B

    2012-04-01

    We present a review of the published evidence on the optimal timing for long bone fracture fixation in severe traumatic brain injury (TBI); a matter that remains under debate. Fifteen retrospective articles (level II-3 evidence) were considered suitable for the review. We conclude that the published evidence does not provide a definitive answer to the optimal timing of long bone fracture surgery in severe TBI, and a randomized controlled trial is required. We recommend a safe strategy that combines damage control surgery with a period of monitoring of intracranial pressure, cerebral perfusion pressure, and if available brain tissue oxygen until the patient is considered fit for the fracture fixation.

  14. A device for continuous monitoring of true central fixation based on foveal birefringence.

    Science.gov (United States)

    Gramatikov, Boris; Irsch, Kristina; Müllenbroich, Marie; Frindt, Nicole; Qu, Yinhong; Gutmark, Ron; Wu, Yi-Kai; Guyton, David

    2013-09-01

    A device for continuous monitoring of central fixation utilizes birefringence, the property of the Henle fibers surrounding the human fovea, to change the polarization state of light. A circular scan of retinal birefringence, where the scanning circle encompasses the fovea, allows identification of true central fixation-an assessment much needed in various applications in ophthalmology, psychology, and psychiatry. The device allows continuous monitoring for central fixation over an extended period of time in the presence of fixation targets and distracting stimuli, which may be helpful in detecting attention deficit hyperactivity disorder, autism spectrum disorders, and other disorders characterized by changes in the subject's ability to maintain fixation. A proof-of-concept has been obtained in a small study of ADHD patients and normal control subjects.

  15. Influence of stability and mechanical properties of a spinal fixation device on production of wear debris particles in vivo.

    Science.gov (United States)

    Mochida, Y; Bauer, T W; Nitto, H; Kambic, H E; Muschler, G F

    2000-01-01

    A prospective and quantitative animal study was performed to evaluate the production of wear particles from a spinal fixation device, and to test the hypothesis that the concentration of wear debris particles adjacent to spinal fixation hardware is correlated with the stiffness of the spinal fusion construct and local bone formation at the fusion site. An established canine segmental spinal fusion model with three interfacet fusions was used in this study. Several bone substitute materials were grafted to the area of the interfacet fusion. Internal fixation was performed on both sides of the spinous processes at each site using a stainless steel plate system in 19 dogs. After 12 weeks, spinal segments were excised, then 3-dimensional computerized tomography was used to measure bone volume and bone area of the individual fusion sites. The stiffness of each segment was tested using a servohydraulic materials testing machine. Biopsies were obtained from the soft tissues immediately around the plate system, and wear particles were collected and characterized using an electrical resistance particle analyzer, light and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX). Biopsies from para-spinal tissue from adjacent, unoperated spinal levels served as negative controls. Histologically, 24 of 57 specimens (42.1%) showed only fibrous tissue with no recognizable macrophages, inflammation, or debris. Fourteen of 57 specimens (24.6%), however, contained many particles that were composed of Fe, Cr, and Ni, corresponding to elements found in the fixation hardware. Another 19 specimens showed only occasional particles. The mean concentration of particles from the tissue around the plate system was 2.8 x 10(9) per gram dry tissue weight, compared to 0.5 x 10(9) particles per gram for controls (p < 0.05). Statistical analyses showed significant inverse correlation between the log particle number and stiffness (r = -0.41, p < 0.01), bone volume (r

  16. Bone compaction enhances fixation of weightbearing titanium implants

    DEFF Research Database (Denmark)

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

    2005-01-01

    Implant stability is crucial for implant survival. A new surgical technique, compaction, has increased in vitro implant stability and in vivo fixation of nonweightbearing implants. However, the in vivo effects of compaction on weightbearing implants are unknown. As implants inserted clinically...... are 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...

  17. Is there enough evidence to regularly apply bone screws for intermaxillary fixation in mandibular fractures?

    NARCIS (Netherlands)

    A. Bins; M.A.E. Oomens; P. Boffano; T. Forouzanfar

    2015-01-01

    Purpose Intermaxillary fixation (IMF) is traditionally achieved with arch bars; however, this method has several well-known disadvantages and other techniques, such as bone screws, are available. This study evaluated current evidence regarding these IMF screws (IMFSs) for mandibular trauma and to as

  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. Bone compaction enhances implant fixation in a canine gap model

    DEFF Research Database (Denmark)

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

    2005-01-01

    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......) were bilaterally inserted into cavities initially expanded to 8 mm diameters in the proximal humeri. Each dog served as its own control; thus, one humerus had the implant cavity prepared with compaction, the other with drilling. Eight dogs were euthanized after 2 weeks, and 7 dogs after 4 weeks. Humeri...... from additional 7 dogs represented time 0. At time 0 a spring-back effect of compacted bone was demonstrated as cavities, initially expanded to 8 mm by compaction, were reduced to a median cavity diameter of 6.6 mm. In contrast, cavities initially expanded to 8 mm by drilling, had a median cavity...

  20. Clamping stiffness and its influence on load distribution between paired internal spinal fixation devices.

    Science.gov (United States)

    Rohlmann, A; Calisse, J; Bergmann, G; Radvan, J; Mayer, H M

    1996-06-01

    The load distribution between two internal spinal fixation devices depends, besides other factors, on their stiffness. The stiffness ranges were determined experimentally for the clamps of the AO internal fixator with lateral nut and with posterior nut as well as for the clamps of the SOCON fixator. The stiffness of eight devices each differed by a factor of 3.1 for the clamp with lateral nut, by a factor of 1.5 for the clamp with posterior nut, and by a factor of 1.4 for the clamp of the SOCON fixator. For the AO clamp with lateral nut, the influence of the nut-tightening torque on the stiffness was determined. Using instrumented internal spinal fixation devices mounted to plastic vertebrae and simulating a corpectomy, the load distribution between the implants was measured for different tightening torques. It could be shown that, for the AO internal fixator whose clamps have a lateral nut, a nut-tightening torque > 5 Nm has only a negligible influence on load-sharing between the implants. Tooth damage occurs when the teeth of the clamp body and clamping jaw of the clamp with lateral nut do not gear together exactly, which leads to changes in the clamping stiffness and load-sharing between the two implants.

  1. Attention attraction in an ophthalmic diagnostic device using sound-modulated fixation targets.

    Science.gov (United States)

    Gramatikov, Boris I; Rangarajan, Shreya; Irsch, Kristina; Guyton, David L

    2016-08-01

    This study relates to eye fixation systems with combined optical and audio systems. Many devices for eye diagnostics and some devices for eye therapeutics require the patient to fixate on a small target for a certain period of time, during which the eyes do not move and data from substructures of one or both eyes are acquired and analyzed. With young pediatric patients, a monotonously blinking target is not sufficient to retain attention steadily. We developed a method for modulating the intensity of a point fixation target using sounds appropriate to the child's age and preference. The method was realized as a subsystem of a Pediatric Vision Screener which employs retinal birefringence scanning for detection of central fixation. Twenty-one children, age 2-18, were studied. Modulation of the fixation target using sounds ensured the eye fixated on the target, and with appropriate choice of sounds, performed significantly better than a monotonously blinking target accompanied by a plain beep. The method was particularly effective with children of ages up to 10, after which its benefit disappeared. Typical applications of target modulation would be as supplemental subsystems in pediatric ophthalmic diagnostic devices, such as scanning laser ophthalmoscopes, optical coherence tomography units, retinal birefringence scanners, fundus cameras, and perimeters.

  2. Silver Nanoparticles in Alveolar Bone Surgery Devices

    Directory of Open Access Journals (Sweden)

    Stefano Sivolella

    2012-01-01

    Full Text Available Silver (Ag ions have well-known antimicrobial properties and have been applied as nanostrategies in many medical and surgical fields, including dentistry. The use of silver nanoparticles (Ag NPs may be an option for reducing bacterial adhesion to dental implant surfaces and preventing biofilm formation, containing the risk of peri-implant infections. Modifying the structure or surface of bone grafts and membranes with Ag NPs may also prevent the risk of contamination and infection that are common when alveolar bone augmentation techniques are used. On the other hand, Ag NPs have revealed some toxic effects on cells in vitro and in vivo in animal studies. In this setting, the aim of the present paper is to summarize the principle behind Ag NP-based devices and their clinical applications in alveolar bone and dental implant surgery.

  3. External fixation of femoral defects in athymic rats: Applications for human stem cell implantation and bone regeneration

    Directory of Open Access Journals (Sweden)

    Terasa Foo

    2013-01-01

    Full Text Available An appropriate animal model is critical for the research of stem/progenitor cell therapy and tissue engineering for bone regeneration in vivo. This study reports the design of an external fixator and its application to critical-sized femoral defects in athymic rats. The external fixator consists of clamps and screws that are readily available from hardware stores as well as Kirschner wires. A total of 35 rats underwent application of the external fixator with creation of a 6-mm bone defect in one femur of each animal. This model had been used in several separate studies, including implantation of collagen gel, umbilical cord blood mesenchymal stem cells, endothelial progenitor cells, or bone morphogenetic protein-2. One rat developed fracture at the proximal pin site and two rats developed deep tissue infection. Pin loosening was found in nine rats, but it only led to the failure of external fixation in two animals. In 8 to 10 weeks, various degrees of bone growth in the femoral defects were observed in different study groups, from full repair of the bone defect with bone morphogenetic protein-2 implantation to fibrous nonunion with collagen gel implantation. The external fixator used in these studies provided sufficient mechanical stability to the bone defects and had a comparable complication rate in athymic rats as in immunocompetent rats. The external fixator does not interfere with the natural environment of a bone defect. This model is particularly valuable for investigation of osteogenesis of human stem/progenitor cells in vivo.

  4. NiTiNol Hernia Device Stability in Inguinal Hernioplasty Without Fixation

    OpenAIRE

    Brown, Roderick B.

    2011-01-01

    Background and Objective: To determine whether the NiTiNol frame of a novel hernia repair device utilizing polypropylene mesh for inguinal hernioplasty remains stable and intransient without fixation after a minimum of 6 months. Methods: Twenty patients had 27 inguinal hernias repaired using a novel hernia repair device that has a NiTiNol frame without any fixation. Initial single-view, postoperative X-rays were compared with a second X-ray obtained at least 6 months later. The NiTiNol frame,...

  5. 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

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

    DEFF Research Database (Denmark)

    Kold, Søren; Rahbek, Ole; Vestermark, Marianne;

    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 8 dogs after 4 weeks. Femoral condyles from additional 7 dogs represented time 0. Compacted specimens had significantly higher bone implant contact and energy absorption at time 0. Compaction significantly increased ultimate shear strength at 0 and 2 weeks. There was no significant difference...... in 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....

  7. 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.

  8. Influence of short-term fixation with mixed formalin or ethanol solution on the mechanical properties of human cortical bone

    OpenAIRE

    Mick E.; Steinke H.; Wolfskämpf T.; Wieding J.; Hammer N.; Schulze M.; Souffrant R.; Bader R.

    2015-01-01

    Bone specimens obtained for biomechanical experiments are fresh-frozen for storage to slow down tissue degradation and autolysis in long-term storage. Alternatively, due to infectious risks related to the fresh tissues, fixative agents are commonly used. However, fixatives will likely change the mechanical properties of bone. Existing studies on this issue gave controversial results that are hardly comparable due to a variety of measurement approaches. For this reason, the influence of ethano...

  9. Augmentation of screw fixation with injectable calcium sulfate bone cement in ovariectomized rats.

    Science.gov (United States)

    Yu, Xiao-Wei; Xie, Xin-Hui; Yu, Zhi-Feng; Tang, Ting-Ting

    2009-04-01

    The objective of this study was to determine the effect of augmenting screw fixation with an injectable calcium sulfate cement (CSC) in the osteoporotic bone of ovariectomized rats. The influence of the calcium sulfate (CS) on bone remodeling and screw anchorage in osteoporotic cancellous bone was systematically investigated using histomorphometric and biomechanical analyses. The femoral condyles of 55 Sprague-Dawley ovariectomized rats were implanted with screw augmented with CS, while the contralateral limb received a nonaugmented screw. At time intervals of 2, 4, 8, 12, and 16 weeks, 11 rats were euthanized. Six pair-matched samples were used for histological analysis, while five pair-matched samples were preserved for biomechanical testing. Histomorphometric data showed that CS augmented screws activated cancellous bone formation, evidenced by a statistically higher (p < 0.05) percentage of osteoid surface at 2, 4, and 8 weeks and a higher rate of bone mineral apposition at 12 weeks compared with nonaugmented screws. The amount of the bone-screw contact at 2, 8, and 12 weeks and of bone ingrowth on the threads at 4 and 8 weeks was greater in the CS group than in the nonaugmented group (p < 0.05), although these parameters increased concomitantly with time for both groups. The CS was resorbed completely at 8 weeks without stimulating fibrous encapsulation on the screw surface. Also, the cement significantly increased the screw pull-out force and the energy to failure at 2, 4, 8, and 12 weeks after implantation, when compared with the control group (p < 0.05). These results imply that augmentation of screw fixation with CS may have the potential to decrease the risk of implant failure in osteoporotic bone.

  10. A numerical simulation of the effect of using porous superelastic Nitinol and stiff Titanium fixation hardware on the bone remodeling

    Science.gov (United States)

    Raad, Bahram; Shayesteh Moghaddam, Narges; Elahinia, Mohammad

    2016-04-01

    The aim of this article is to investigate the effect of two different fixation hardware materials on bone remodeling after a mandibular reconstruction surgery and to restore the mandible's function, healthy appearance, mastication, swallowing, breathing, and speech. The hypothesis is that using fixation hardware with stiffness close to that of the surrounding bone will result in a more successful healing process in the mandible bone. The finite element model includes the material properties and forces of the cancellous bone, cortical bone, ligaments, muscles, and teeth. The reconstruction surgery is modeled by including the fixation hardware and the grafted bone. In the sectioned mandible, to best mimic the geometry of the mandible, two single barrel grafts are placed at the top of each other to form a double barrel graft set. Two different materials were used as the mandibular fixation parts, stiff Ti-6Al-4V, and porous superelastic Nickel-Titanium (NiTi) alloys. A comparison of these two alloys demonstrates that using porous NiTi alloy as the fixation part results in a faster healing pace. Furthermore, the density distribution in the mandibular bone after the healing process is more similar to the normal mandible density distribution. The simulations results indicate that the porous superelastic NiTi fixation hardware transfers and distributes the existing forces on the mandible bone more favorably. The probability of stress shielding and/or stress concentration decrease. This type of fixation hardware, therefore, is more appropriate for mandible bone reconstruction surgery. These predictions are in agreement with the clinical observations.

  11. Bone radiofrequency ablation combined with prophylactic internal fixation for metastatic bone tumor of the femur from hepatocellular carcinoma.

    Science.gov (United States)

    Ogura, Koichi; Miyake, Ryoko; Shiina, Shuichiro; Shinoda, Yusuke; Okuma, Tomotake; Kobayashi, Hiroshi; Goto, Takahiro; Nakamura, Kozo; Kawano, Hirotaka

    2012-08-01

    A 64-year-old man with 6-year history of hepatocellular carcinoma (HCC) was referred to us regarding bone metastasis to the right proximal femur. Although he underwent radiotherapy for pain palliation and local tumor control, the pain persisted and the tumor relapsed 3 months after the radiotherapy and he was thought to be at high risk of pathologic fracture. Given hypervascularity and large tumor size, a prophylactic internal fixation combined with adjuvant radiofrequency ablation (RFA) was proposed to reduce blood loss and prevent viable tumor cells being disseminated. His postoperative course was uneventful without requiring blood transfusion and preoperative symptoms immediately disappeared after surgery. He became capable of weight-bearing walk with a single cane and was almost asymptomatic without local progression on the plain radiographs when he died 14 months after surgery. Combination therapy of RFA and internal fixation using intramedullary nailing for metastases of the long bones from HCC seems to be a very promising technique both for sufficient pain relief and for local control of the tumor. Adjuvant RFA may become a potential option for patients with metastases of the long bones for the purpose of prevention of tumor dissemination and reduction of intraoperative blood loss.

  12. 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

  13. Titanium alloys as fixation device material for cranioplasty and its safety in electroconvulsive therapy.

    Science.gov (United States)

    Kaido, Takanobu; Noda, Takamasa; Otsuki, Taisuke; Kaneko, Yuu; Takahashi, Akio; Nakai, Tetsuji; Nabatame, Maki; Tani, Mariko

    2011-03-01

    Here, we report the case of a patient successfully treated by a series of electroconvulsive therapy (ECT) who had implanted skull fixation devices made of titanium alloy. The patient was a 57-year-old man with bipolar I disorder. He was hospitalized for the treatment of manic symptoms of bipolar I disorder with pharmacotherapy and ECT. He sustained a fall and hit his head hard on the ground. Acute subdural hematoma developed, and emergent surgery to remove the hematoma was carried out. Cranioplasty was performed using fixation devices made of titanium alloy (Ti 6Al-4V). In order to control his manic symptoms, a series of ECT was readministered from 1 week after surgery. No adverse effects occurred. Devices must be investigated and chosen very carefully for permanent implantation, especially in patients during a course of ECT.

  14. 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...

  15. 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

  16. 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

  17. A novel technique of lumbar hernia repair using bone anchor fixation.

    Science.gov (United States)

    Carbonell, A M; Kercher, K W; Sigmon, L; Matthews, B D; Sing, R F; Kneisl, J S; Heniford, B T

    2005-03-01

    Lumbar hernias are difficult to repair due to their proximity to bone and inadequate surrounding tissue to buttress the repair. We analyzed the outcome of patients undergoing a novel retromuscular lumbar hernia repair technique. The repair was performed in ten patients using a polypropylene or polytetrafluoroethylene mesh placed in an extraperitoneal, retromuscular position with at least 5 cm overlap of the hernia defect. The mesh was fixed with circumferential, transfascial, permanent sutures and inferiorly fixed to the iliac crest by suture bone anchors. Five hernias were recurrent, and five were incarcerated; seven were incisional hernias, and three were posttraumatic. Back and abdominal pain was the most common presenting symptom. Mean hernia size was 227 cm(2) (60-504) with a mesh size of 620 cm(2) (224-936). Mean operative time was 181 min (120-269), with a mean blood loss of 128 ml (50-200). Mean length of stay was 5.2 days (2-10), and morphine equivalent requirement was 200 mg (47-460). There were no postoperative complications or deaths. After a mean follow-up of 40 months (3-99) there have been no recurrences. Our sublay repair of lumbar hernias with permanent suture fixation is safe and to date has resulted in no recurrences. Suture bone anchors ensure secure fixation of the mesh to the iliac crest and may eliminate a common area of recurrence.

  18. Evaluation of different rotary devices on bone repair in rabbits

    OpenAIRE

    Ribeiro Junior, Paulo Domingos; Barleto, Christiane Vespasiano; Ribeiro,Daniel Araki; Matsumoto,Mariza Akemi

    2007-01-01

    In oral surgery, the quality of bone repair may be influenced by several factors that can increase the morbidity of the procedure. The type of equipment used for ostectomy can directly affect bone healing. The aim of this study was to evaluate bone repair of mandible bone defects prepared in rabbits using three different rotary devices. Fifteen New Zealand rabbits were randomly assigned to 3 groups (n=5) according to type of rotary device used to create bone defects: I - pneumatic low-speed r...

  19. A STUDY ON FUNCTIONAL OUTCOME OF ILIZAROV FIXATION IN THE MANAGEMENT OF INFECTED NONUNION OF LONG BONES

    Directory of Open Access Journals (Sweden)

    Vellanki

    2016-01-01

    Full Text Available Healing of non-union infected fracture bones like tibia is a challenging one. Ilizarov external ring fixation is the appropriate method. The aim of our study is to evaluate the efficacy of Ilizarov external ring fixator in infected nonunion of bones and functional results in 20 patients and to conduct the study of complications. The age group included in our study were between 30 to 40 years of the 20 cases 17 were males and 3 were females. Of the 20 cases in our study, 14 cases had excellent results, 4 cases had good outcome, 1 patient had fair outcome, 1 cases had poor outcome. The study shows that Ilizarov ring external fixator system is ideal for limb salvage in infected nonunion of long bones.

  20. Long-term implant-bone fixation of the femoral component in total knee replacement.

    Science.gov (United States)

    Cristofolini, L; Affatato, S; Erani, P; Leardini, W; Tigani, D; Viceconti, M

    2008-04-01

    Success of total knee replacement (TKR) depends on the prosthetic design. Aseptic loosening of the femoral component is a significant failure mode that has received little attention. Despite the clinical relevance of failures, no protocol is available to test long-term implant-bone fixation of TKR in vitro. The scope of this work was to develop and validate a protocol to assess pre-clinically the fixation of TKR femoral components. An in vitro protocol was designed to apply a simplified but relevant loading profile using a 6-degrees-of-freedom knee simulator for 1,000000 cycles. Implant-bone inducible micromotions and permanent migrations were measured at three locations throughout the test. After test completion, fatigue damage in the cement was quantified. The developed protocol was successfully applied to a commercial TKR. Additional tests were performed to exclude artefacts due to swelling or creep of the composite femur models. The components migrated distally; they tilted towards valgus in the frontal plane and in extension in the sagittal plane. The migration patterns were consistent with clinical roentgen-stereophotogrammetric recordings with TKR. Additional indicators were proposed that could quantify the tendency to loosen/stabilize. The type and amount of damage found in the cement, as well as the migration patterns, were consistent with clinical experience with the specific TKR investigated. The proposed pre-clinical test yielded repeatable results, which were consistent with the clinical literature. Therefore, its relevance and reliability was proved.

  1. Antimicrobial activity of nanocomposite zirconium nitride/silver coatings to combat external bone fixation pin infections.

    Science.gov (United States)

    Wickens, David J; West, Glen; Kelly, Peter J; Verran, Joanna; Lynch, Stephen; Whitehead, Kathryn A

    2012-10-01

    During external fixation, temporary implants are used to penetrate the skin, muscle and bone to support severely fractured bones. This creates a biologically critical interface at the site of entry, which potentially allows a risk of infection. The aim of this study, therefore, was to investigate potential antimicrobial nanocomposites to combat infection. Magnetron sputtering was used to produce zirconium nitride/silver nanocomposite coatings, which were prepared at two different silver concentrations of 15.5 at.% and 29.8 at.%. These coatings were characterized for morphology, chemical composition, and antimicrobial activity in comparison to pure zirconium nitride and stainless steel. Staphylococcus aureus and Staphylococcus epidermidis were used as in vitro test organisms in a range of antimicrobial assays; retention of the bacteria on the surfaces and their survival using LiveDead™ staining; the use of a metabolic redox dye to indicate a contact kill and zone of inhibition assays to indicate leaching of inhibitory silver ions. Antimicrobial tests demonstrated a significant kill when the bacterial cells came in contact with the coatings containing silver at both 15.5 at.% and 29.8 at.%. No inhibitory leaching from the surfaces occurred. These surfaces demonstrate potential for use as antimicrobial fixation pin coatings.

  2. 3D perfusion bioreactor-activated porous granules on implant fixation and early bone formation in sheep

    DEFF Research Database (Denmark)

    Ding, Ming; Snoek Henriksen, Susan; Martinetti, Roberta

    2017-01-01

    Early fixation of total joint arthroplasties is crucial for ensuring implant survival. An alternative bone graft material in revision surgery is needed to replace the current gold standard, allograft, seeing that the latter is associated with several disadvantages. The incubation of such a constr......, bone formation was observed in all groups, while the bioreactor-activated graft material did not reveal additional effects on early implant fixation comparable to allograft in this model. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016....

  3. Radiation-Associated Fracture Nonunion of the Clavicle Treated with Locking Plate Fixation and Autologous Bone Grafting

    Directory of Open Access Journals (Sweden)

    Takahiro Niikura

    2012-01-01

    Full Text Available We describe a case of radiation-associated fracture nonunion of the clavicle, which was treated by locking plate fixation and autologous bone grafting. The patient was a 67-year old man who received 70 Gy radiation therapy to treat nasopharyngeal carcinoma. Eight years later, he suffered a pathological fracture of the right clavicle. One year after the fracture, surgical treatment was performed due to persistent pain and weakness. Radiographs demonstrated atrophic nonunion. Bone scan demonstrated hot uptake at both ends of the fractured bone. MRI demonstrated a formation of pseudoarthrosis with fluid collection and suggested bone marrow edema at both ends of the fracture fragments. In surgery, fibrous pseudoarthrosis tissue was excised and both ends of the fracture fragments were refreshed to identify bleeding. Open reduction and internal fixation using a 7-hole locking plate and autologous bone grafting were performed. Successful bony union was obtained 1 year postoperatively, and no adverse events were observed up to 52 months after the operation. Our case suggests that a locking plate provides sufficient fixation and autologous bone grafting is effective in enhancing bone healing in a radiation-associated fracture nonunion of the clavicle in which it is difficult to achieve bony union.

  4. 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.

  5. Influence of short-term fixation with mixed formalin or ethanol solution on the mechanical properties of human cortical bone

    Directory of Open Access Journals (Sweden)

    Mick E.

    2015-09-01

    Full Text Available Bone specimens obtained for biomechanical experiments are fresh-frozen for storage to slow down tissue degradation and autolysis in long-term storage. Alternatively, due to infectious risks related to the fresh tissues, fixative agents are commonly used. However, fixatives will likely change the mechanical properties of bone. Existing studies on this issue gave controversial results that are hardly comparable due to a variety of measurement approaches. For this reason, the influence of ethanol and a formalin-based fixative agent was evaluated on the mechanical properties of human cortical bone specimens by means of four-point-bending tests. 127 prismatic specimens with rectangular cross sections (2.5 x 2.5 x 20 mm3 were obtained from different regions of two fresh human femora (medial, lateral, dorsal, ventral. Specimens were either fixed in ethanol or in a mixed formalin solution or frozen following a given scheme. After two weeks of storage the samples were re-hydrated in isotonic saline and subsequently tested mechanically. The elastic bending modulus and ultimate bending strength were computed considering the actual dimensions of each specific specimen. For statistical analysis a one-way-ANOVA and an LSD post-hoc-test were performed. For ultimate bending strength no significant differences due to formalin or ethanol fixation, as compared to unfixed-fresh bone specimens could be found. And only for few cases significant differences in elastic bending modulus were observed when the two bones were evaluated separately. Since more differences of significant level due to the anatomical region of the samples were determined, the original location seems to have more influence on the evaluated mechanical properties than the method of (chemical fixation. Consequently, ethanol and the mixed formalin solution can be recommended as a fixation agent for samples in biomechanical testing, if these samples are rinsed in isotonic saline prior to static

  6. Posterior lumbar interbody fusion with cortical bone trajectory screw fixation versus posterior lumbar interbody fusion using traditional pedicle screw fixation for degenerative lumbar spondylolisthesis: a comparative study.

    Science.gov (United States)

    Sakaura, Hironobu; Miwa, Toshitada; Yamashita, Tomoya; Kuroda, Yusuke; Ohwada, Tetsuo

    2016-11-01

    OBJECTIVE Several biomechanical studies have demonstrated the favorable mechanical properties of the cortical bone trajectory (CBT) screw. However, no reports have examined surgical outcomes of posterior lumbar interbody fusion (PLIF) with CBT screw fixation for degenerative spondylolisthesis (DS) compared with those after PLIF using traditional pedicle screw (PS) fixation. The purposes of this study were thus to elucidate surgical outcomes after PLIF with CBT screw fixation for DS and to compare these results with those after PLIF using traditional PS fixation. METHODS Ninety-five consecutive patients underwent PLIF with CBT screw fixation for DS (CBT group; mean followup 35 months). A historical control group consisted of 82 consecutive patients who underwent PLIF with traditional PS fixation (PS group; mean follow-up 40 months). Clinical status was assessed using the Japanese Orthopaedic Association (JOA) scale score. Fusion status was assessed by dynamic plain radiographs and CT. The need for additional surgery and surgery-related complications was also evaluated. RESULTS The mean JOA score improved significantly from 13.7 points before surgery to 23.3 points at the latest follow-up in the CBT group (mean recovery rate 64.4%), compared with 14.4 points preoperatively to 22.7 points at final follow-up in the PS group (mean recovery rate 55.8%; p fusion was achieved in 84 patients from the CBT group (88.4%) and in 79 patients from the PS group (96.3%, p > 0.05). Symptomatic adjacent-segment disease developed in 3 patients from the CBT group (3.2%) compared with 9 patients from the PS group (11.0%, p fusion rate tended to be lower in the CBT group than in the PS group, although the difference was not statistically significant between the 2 groups.

  7. Arthroscopic suture fixation in patients with a tibial intercondylar eminence fracture using a simple device to penetrate the anterior cruciate ligament

    Directory of Open Access Journals (Sweden)

    Masato Aratake

    2014-04-01

    Full Text Available Displaced tibial intercondylar eminence fractures require early reduction and stable fixation to prevent nonunion, knee instability, and a lack of extension. Many types of surgical procedure are recommended including arthrotomy or an arthroscopic technique to stabilize the fracture segment using Kirschner wire, screws, staples, and suture fixation. However, contemporary arthroscopic techniques and devices can facilitate intra-articular surgery and have been applied to the treatment of this fracture. In our current report, we describe a simple suture fixation method under arthroscopy for the treatment of tibial intercondylar eminence fractures. We treated eight knees of eight patients. One patient had a Type II fracture and seven patients had a Type III fracture according to Meyer's classification. Following the arthroscopic inspection of concomitant injuries, debridement of hematoma, and reduction of the fragment, two nonabsorbable sutures (Ethibond No. 2, Johnson & Johnson, Somerville, NJ, USA were advanced through the suture passer device, which is used to penetrate the anterior cruciate ligament (ACL near to the insertion site of the displaced fragment. Two surgical sutures were pulled out by the suture retriever from the anterior proximal tibia hole and were fixed to the tibia cortex bone with a double-spike plate. At follow-up, radiographic examinations showed that bone union was achieved in all cases. All but one patient could resume normal activities with no restrictions and no ligamentous instability. All knees had a negative Lachman's test and showed a gain of stable ligament function by KT2000 arthrometer evaluation. One patient had an insignificant extension limitation and experienced slight pain after walking but these symptoms were minimal. In conclusion current arthroscopic surgery techniques for tibial intercondylar fractures can be easily performed and reproducibly achieve secure fixation and early mobilization of the knee.

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

    Science.gov (United States)

    Ding, Ming; Andreasen, Christina M; Dencker, Mads L; Jensen, Anders E; Theilgaard, Naseem; Overgaard, Søren

    2015-04-01

    Cylindrical critical size defects were created at the distal femoral condyles bilaterally of eight female adult sheep. Titanium implants with 2-mm concentric gaps were inserted and the gaps were filled with one of the four materials: allograft; a synthetic 15-amino acid cell-binding peptide coated 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 be observed in all four groups. Interestingly, the microarchitecture of the ABM/P-15 group was significantly different from the control group. Tissue volume fraction and thickness were significantly greater in the ABM/P-15 group than in the allograft group. Bone formation and bone ingrowth to porous titanium 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 formation in concentric gap, and its enhancements on bone formation and implant fixation were at least as good as allograft. It is suggested that ABM/P-15 might be a good alternative biomaterial for bone implant fixation in this well-validated critical-size defect gap model in sheep. Nevertheless, future clinical researches should focus on prospective, randomized, controlled trials in order to fully elucidate whether ABM/P-15 could be a feasible candidate for bone substitute material in orthopedic practices.

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

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    Denmark, DenmarkAbstractReplacement 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 standard for bone replacement. However, there are several disadvantages such as donor site...... 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 concentric gap of 2 mm were implanted in each sheep. The gap was filled with: DBM; DBM/CB with ratio of 1/3; DBM/allograft with ratio of 1/3; or allograft (Gold standard), respectively. Standardised surgical procedure was used1. At sacrifice, 6 weeks after surgery, both distal femurs were harvested...

  11. Thoracolumbar spinal fractures : radiological results of transpedicular fixation combined with transpedicular cancellous bone graft and posterior fusion in 183 patients

    NARCIS (Netherlands)

    Leferink, VJM; Zimmerman, KW; Veldhuis, EFM; ten Vergert, EM; ten Duis, HJ

    2001-01-01

    In internal posterior fixation of thoracolumbar fractures combined with transpedicular cancellous bone graft and posterior fusion of the intervertebral facet joints at the level of the destroyed end plate it is still uncertain as to whether significant vertebral body collapse and loss of correction

  12. A modified cementing technique using BoneSource to augment fixation of the acetabulum in a sheep model.

    NARCIS (Netherlands)

    Timperley, A.J.; Nusem, I.; Wilson, K.; Whitehouse, S.L.; Buma, P.; Crawford, R.W.

    2010-01-01

    BACKGROUND AND PURPOSE: Our aim was to assess in an animal model whether the use of HA paste at the cement-bone interface in the acetabulum improves fixation. We examined, in sheep, the effect of interposing a layer of hydroxyapatite cement around the periphery of a polyethylene socket prior to fixi

  13. Three-dimensional stabilization provided by the external spinal fixator compared to two internal fixation devices: a biomechanical in vitro flexibility study.

    Science.gov (United States)

    Lund, Teija; Nydegger, Thomas; Rathonyi, Gabor; Nolte, Lutz-Peter; Schlenzka, Dietrich; Oxland, Thomas R

    2003-10-01

    We performed an in vitro study to investigate the stabilization (i.e. motion reduction) provided by the external spinal fixator (ESF), and to compare the three configurations of the ESF with two internal fixation techniques. Six human cadaveric lumbar spine specimens (L3-S1) were subjected to multidirectional flexibility testing in six configurations: (1) intact, (2) ESF in neutral, (3) ESF in distraction, (4) ESF in compression, (5) translaminar facet screw fixation, and (6) internal transpedicular fixation. Both the ESF and the internal fixation systems stabilized the specimens from L4 to S1. In each testing configuration, pure bending moments of flexion-extension, bilateral axial rotation, and bilateral lateral bending were applied to the uppermost vertebra stepwise to a maximum of 10 Nm. The rigid body motion between the vertebrae was measured using an optoelectronic camera system, and custom software was used to calculate the intervertebral rotations. For each applied motion in all testing configurations, the total range of motion (ROM) of L4-S1 is reported. All three ESF configurations stabilized the spine significantly when compared to the intact specimen. The ESF in compression provided significantly more stabilization in flexion-extension than the two other ESF configurations, but no other significant differences were found between the three ESF modes. In flexion-extension the ESF stabilized the spine significantly when compared with the two internal fixation devices. Only in bilateral lateral bending was the ESF inferior to internal transpedicular fixation in providing stabilization. The results of the present study suggest that the ESF provides a high degree of stabilization for preoperative assessment of selected low back pain patients. Whether other non-mechanical factors affect the pain relief experienced by the patients remains unknown.

  14. HYBRID EXTERNAL FIXATOR FOR THE TREATMENT OF UNICAMERAL BONE CYSTS WITH PATHOLOGICAL FRACTURE IN THE PROXIMAL HUMERUS

    Institute of Scientific and Technical Information of China (English)

    郭征; 王臻; 赵黎

    2004-01-01

    Objective: Unicameral bone cyst is a nonneoplastic bone lesion characterized by its tenacity and risk of recurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of hybrid external fixator for the treatment of a unicameral bone cyst with a pathological fracture. Methods: Hybrid external fixator for the treatment of a unicameral bone cyst was performed in twelve patients. These patients presented with a pathological fracture and were managed immediately with hybrid external fixator, of whom four had been managed conservatively at other clinics before they were referred to our department. The cyst was located in the proximal humerus in all patients. The mean age of the patients at the time of surgery was 8.7 years, and the mean duration of follow-up was 32.6 months. Radiographic evaluation was performed according to the criteria of Capanna et al., and the cyst was classified as completely healed, healed with residual radiolucency (osteolysis), recurred, or having no response. Results: The healing period ranged from three to eight months. Eight cysts healed completely, and three healed with residual radiolucent areas visible on radiographs. There was recurrence of one cyst that had healed with residual radiolucency. All of the cysts in the present study responded to treatment. A modulation of hybrid external fixator was necessary in three patients, as the bars had become too short after bone growth or the pins had been loose. No major complications were observed.Conclusion: Hybrid external fixator provides early stability, which allows early mobilization and thus obviates the need for a plaster cast. This method of treatment also allows for an early return to normal activity.

  15. A novel combined method of osteosynthesis in treatment of tibial fractures: a comparative study on sheep with application of rod-through-plate fixator and bone plating.

    Science.gov (United States)

    Tralman, G; Andrianov, V; Arend, A; Männik, P; Kibur, R T; Nõupuu, K; Uksov, D; Aunapuu, M

    2013-04-01

    The study compares the efficiency of a new bone fixator combining periostal and intramedullary osteosynthesis to bone plating in treatment of tibial fractures in sheep. Experimental osteotomies were performed in the middle third of the left tibia. Animals were divided into two groups: in one group (four animals) combined osteosynthesis (rod-through-plate fixator, RTP fixator) was applied, and in the other group (three animals) bone plating was used. The experiments lasted for 10 weeks during which fracture union was followed by radiography, and the healing process was studied by blood serum markers reflecting bone turnover and by histological and immunohistochemical investigations. In the RTP fixator group, animals started to load body weight on the operated limbs the next day after the surgery, while in the bone plating group, this happened only on the seventh day. In the RTP fixator group, consolidation of fractures was also faster, as demonstrated by radiographical, histological, and immunohistochemical investigations and in part by blood serum markers for bone formation. It can be concluded that application of RTP fixation is more efficient than plate fixation in the treatment of experimental osteotomies of long bones in sheep.

  16. Fixation of trapezial implants in a trapeziometacarpal total joint prosthesis tested in a model of porcine bone.

    Science.gov (United States)

    Hansen, Torben Bæk; Hengst, David; Mortensen, Jesper; Amstrup, Anders Læssøe

    2011-12-01

    High aseptic loosening rates have been reported in total joint prostheses of the carpometacarpal joint of the thumb, particularly in the trapezial component. The primary fixation of new implants may be tested in cadaver bones, but the anatomy of the pig is in many ways similar to that of the human, so we compared the central carpal bone from the forefoot of 6-month-old pigs, which has a saddle joint surface similar to the trapezium, to the trapezium in patients with carpometacarpal osteoarthritis. The mean (SD) bone mineral density of the 13 pig forefoot bones was 0.88 (0.12) g/cm(2) compared with 0.63 (0.16) g/cm(2) in the 31 human trapeziums. The measured size of the porcine bones was slightly larger than that of the human trapeziums. The similarity in form, size, and bone mineral density means that the central bone of the forefoot of 6-month-old pigs may be used for fixation tests in trapezial implants.

  17. Osteogenic protein-1 increases the fixation of implants grafted with morcellised bone allograft and ProOsteon bone substitute: an experimental study in dogs

    DEFF Research Database (Denmark)

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

    2007-01-01

    (ProOsteon) would improve the incorporation of bone and implant fixation. We also compared the response to using ProOsteon alone against bone allograft used in isolation. We implanted two non-weight-bearing hydroxyapatite-coated implants into each proximal humerus of six dogs, with each implant...... surrounded by a concentric 3 mm gap. These gaps were randomly allocated to four different procedures in each dog: 1) bone allograft used on its own; 2) ProOsteon used on its own; 3) allograft and ProOsteon used together; or 4) allograft and ProOsteon with the addition of osteogenic protein-1. After three...

  18. Review of techniques for monitoring the healing fracture of bones for implementation in an internally fixated pelvis.

    Science.gov (United States)

    Wong, Lydia Chwang Yuh; Chiu, Wing Kong; Russ, Matthias; Liew, Susan

    2012-03-01

    Sacral fractures from high-impact trauma often cause instability in the pelvic ring structure. Treatment is by internal fixation which clamps the fractured edges together to promote healing. Healing could take up to 12 weeks whereby patients are bedridden to avoid hindrances to the fracture from movement or weight bearing activities. Immobility can lead to muscle degradation and longer periods of rehabilitation. The ability to determine the time at which the fracture is stable enough to allow partial weight-bearing is important to reduce hospitalisation time. This review looks into different techniques used for monitoring the fracture healing of bones which could lead to possible methods for in situ and non-invasive assessment of healing fracture in a fixated pelvis. Traditional techniques being used include radiology and CT scans but were found to be unreliable at times and very subjective in addition to being non in situ. Strain gauges have proven to be very effective for accurate assessment of fracture healing as well as stability for long bones with external fixators but may not be suitable for an internally fixated pelvis. Ultrasound provides in situ monitoring of stiffness recovery but only assesses local fracture sites close to the skin surface and has only been tested on long bones. Vibration analysis can detect non-uniform healing due to its assessment of the overall structure but may suffer from low signal-to-noise ratio due to damping. Impedance techniques have been used to assess properties of non-long bones but recent studies have only been conducted on non-biological materials and more research needs to be done before it can be applicable for monitoring healing in the fixated pelvis.

  19. Locking plate fixation combined with iliac crest bone autologous graft for proximal humerus comminuted fracture

    Institute of Scientific and Technical Information of China (English)

    Zhu Lian; Liu Yueju; Yang Zongyou; Li Han; Wang Juan; Zhao Changping; Chen Xiao

    2014-01-01

    Background Although the use of an intramedullary fibular allograft together with locking plate fixation can provide additional medial support and prevent varus malalignment in displaced proximal humeral fractures with promising results,the fibular autograft donor site often sustains significant trauma and cannot restore the articular surface of comminuted fractures.The aim of this study was to evaluate the clinical and radiographic outcomes of a locking plate and crest bone autologous graft for treating proximal humerus comminuted fractures.Methods We assessed the functional outcomes and complication rates in 40 patients with proximal humerus comminuted fractures.Eighteen patients were treated with a locking plate and an autologous crest bone graft (experimental group),and 22 were treated with only the locking plate and no bone graft (control group).Postoperative assessments included radiographic imaging,range of motion analysis,pain level based on the visual analogue scale (VAS),and the SF-36 (Short Form (36) Health Survey),as well as whether patients could retum to their previous occupation.Results All fractures healed both clinically and radiologically in the experimental group.There was no more than 2 mm collapse of the humeral head,and no osteonecrosis or screw penetration of the articular surface.In contrast,two patients had a nonunion in the control group,and they eventually accepted total shoulder replacements.The average time from surgery to radiographic union was significantly shorter in the experimental group ((4.66±1.63) months) compared with the control group ((5.98±1.57) months) (P <0.05).For the experimental versus controls groups,the mean shoulder active flexion (148.00±18.59 vs.121.73±17.20) degrees,extension (49.00±2.22 vs.42.06±2.06) degrees,internal rotation (45.00±5.61 vs.35.00±3.55)degrees,external rotation (64.00±9.17 vs.52.14±5.73)degrees,and abduction (138.00±28.78 vs.105.95±15.66) degrees were all significantly higher (all P

  20. Characterization of short-fibre reinforced thermoplastics for fracture fixation devices.

    Science.gov (United States)

    Brown, S A; Hastings, R S; Mason, J J; Moet, A

    1990-10-01

    This study focuses on determining the effects of clinically relevant procedures on the flexural and fracture toughness properties of three short-fibre thermoplastic composites for potential application as fracture fixation devices. The procedures included sterilization, heat contouring and saline soaking. The three materials tested were polysulphone, polybutylene terephthalate and polyetheretherketone, all reinforced with 30% short carbon fibres. The polysulphone composite showed significant degradation in mechanical properties due to saline soaking. The polybutylene terephthalate exhibited significant degradation of mechanical properties following both contouring and saline soaking. The polyetheretherketone composite, however, exhibited no degradation in mechanical properties. The results demonstrated that flexion and fracture toughness testing were effective for determining the response of the composites to different applied conditions and demonstrated the stability of polyetheretherketone subjected to these treatments. Scanning electron microscopy demonstrated the most effective fibre-matrix bonding to be in the polyetheretherketone.

  1. Mechanical performance of external fixators with wires for the treatment of bone fractures--Part I: Load-displacement behavior.

    Science.gov (United States)

    Delprete, C; Gola, M M

    1993-02-01

    Using matrix algebra, a mathematical model is formulated for a particular type of external fixator with wires (system developed by Ilizarov) for the treatment of bone fractures. The mathematical model is used to give a linear estimate of the stiffness under lateral and axial loads in a representative number of practical conditions. Relative displacements of the bone ends at the fracture site are calculated not only in the common case of a gap, but also for various angles of inclined sliding contact; in this case, a realistic load is applied and nonlinear stiffening of the wires under transversal loads is iteratively taken into account.

  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. Should in the treatment of osteochondritis dissecans biodegradable or metallic fixation devices be used? A comparative study in goat knees

    NARCIS (Netherlands)

    Wouters, Diederick B.; Bos, Rudolf R. M.; van Horn, Jim R.; van Luyn, Marja J. A.

    2008-01-01

    Most of the metallic devices have to be removed, treating osteochondritis dissecans lesions. This animal study describes the biological and mechanical behavior of screws and pins, made of commercially available PGA/PLA and PLA96 and metallic screws and pins, used for fragment fixation. A sham operat

  4. Bioabsorbable bone fixation plates for X-ray imaging diagnosis by a radiopaque layer of barium sulfate and poly(lactic-co-glycolic acid).

    Science.gov (United States)

    Choi, Sung Yoon; Hur, Woojune; Kim, Byeung Kyu; Shasteen, Catherine; Kim, Myung Hun; Choi, La Mee; Lee, Seung Ho; Park, Chun Gwon; Park, Min; Min, Hye Sook; Kim, Sukwha; Choi, Tae Hyun; Choy, Young Bin

    2015-04-01

    Bone fixation systems made of biodegradable polymers are radiolucent, making post-operative diagnosis with X-ray imaging a challenge. In this study, to allow X-ray visibility, we separately prepared a radiopaque layer and attached it to a bioabsorbable bone plate approved for clinical use (Inion, Finland). We employed barium sulfate as a radiopaque material due to the high X-ray attenuation coefficient of barium (2.196 cm(2) /g). The radiopaque layer was composed of a fine powder of barium sulfate bound to a biodegradable material, poly(lactic-co-glycolic acid) (PLGA), to allow layer degradation similar to the original Inion bone plate. In this study, we varied the mass ratio of barium sulfate and PLGA in the layer between 3:1 w/w and 10:1 w/w to modulate the degree and longevity of X-ray visibility. All radiopaque plates herein were visible via X-ray, both in vitro and in vivo, for up to 40 days. For all layer types, the radio-opacity decreased with time due to the swelling and degradation of PLGA, and the change in the layer shape was more apparent for layers with a higher PLGA content. The radiopaque plates released, at most, 0.5 mg of barium sulfate every 2 days in a simulated in vitro environment, which did not appear to affect the cytotoxicity. The radiopaque plates also exhibited good biocompatibility, similar to that of the Inion plate. Therefore, we concluded that the barium sulfate-based, biodegradable plate prepared in this work has the potential to be used as a fixation device with both X-ray visibility and biocompatibility.

  5. Investigation of the mechanical properties and failure modes of hybrid natural fiber composites for potential bone fracture fixation plates.

    Science.gov (United States)

    Manteghi, Saeed; Mahboob, Zia; Fawaz, Zouheir; Bougherara, Habiba

    2017-01-01

    The purpose of this study is to investigate the mechanical feasibility of a hybrid Glass/Flax/Epoxy composite material for bone fracture fixation such as fracture plates. These hybrid composite plates have a sandwich structure in which the outer layers are made of Glass/Epoxy and the core from Flax/Epoxy. This configuration resulted in a unique structure compared to prior composites proposed for similar clinical applications. In order to evaluate the mechanical properties of this hybrid composite, uniaxial tension, compression, three-point bending and Rockwell Hardness tests were conducted. In addition, water absorption tests were performed to investigate the rate of water absorption for the specimens. This study confirms that the proposed hybrid composite plates are significantly more flexible axially compared to conventional metallic plates. Furthermore, they have considerably higher ultimate strength in tension, compression and flexion. Such high strength will ensure good stability of bone-implant construct at the fracture site, immobilize adjacent bone fragments and carry clinical-type forces experienced during daily normal activities. Moreover, this sandwich structure with stronger and stiffer face sheets and more flexible core can result in a higher stiffness and strength in bending compared to tension and compression. These qualities make the proposed hybrid composite an ideal candidate for the design of an optimized fracture fixation system with much closer mechanical properties to human cortical bone.

  6. Healing pattern of reamed bone following bone harvesting by a RIA device

    Directory of Open Access Journals (Sweden)

    DM Devine

    2015-01-01

    Full Text Available Intramedullary nailing has been used for decades to treat fractures of the long bones. However, complications related to the increase in medullary pressure culminated in the development of the Reamer Irrigator Aspirator (RIA. Since its first clinical use, the RIA has moved from a reaming device to a cell and autologous bone-harvesting tool. This increase in use brings with it further clinical questions; namely, does the endosteal bone regenerate sufficiently to allow subsequent reaming procedures. In the current study, endosteal bone regeneration post reaming was assessed in an ovine model. The study included six animals that had one tibia reamed, while the contralateral tibia acted as an intact control. Animals were administered fluorochrome labels in vivo, and bone regeneration was assessed using radiographical analysis. The endpoint of the study was 12 weeks post-surgery, at which time ex vivo analysis consisted of computed tomography and histological assessments. In vivo radiographs indicated limited healing of the reamed bone. However, ex vivo computer tomographical analysis indicated no significant differences in terms of bone volume between the reamed bone and the intact bone. Histological assessment of these regions indicated new bone formation. Fluorescent labelling indicates strong bone formation from 9 weeks post-surgery and as such, the bone formed at 12 weeks was immature in nature and was actively undergoing remodelling. These results indicate that bone regeneration post-reaming was continuing at three months. Therefore, given more time it may have sufficiently healed to allow a surgeon to use the intramedullary canal for a re-reaming procedure.

  7. Poly(L-lactide) bone plates and screws for internal fixation of mandibular swing osteotomies

    NARCIS (Netherlands)

    Tams, J; Rozema, FR; Bos, RRM; Roodenburg, JLN; Nikkels, PGJ; Vermey, A

    1996-01-01

    This study evaluated bone healing after mandibular swing osteotomies fixed with biodegradable poly(L-lactide) (PLLA) bone plates in four patients. A step osteotomy treated with two PLLA bone plates (n=3), and a straight osteotomy treated with one PLLA bone plate (n=1) were performed. Bone healing wa

  8. Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density?

    Science.gov (United States)

    Zderic, I.; Grechenig, S.; Richards, R. G.; Schmitz, P.; Gueorguiev, B.

    2017-01-01

    Objectives Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. Materials and Methods A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm3 (standard deviation (sd) 52). The anterior pelvic ring fracture was fixed with either one 7.3 mm cannulated screw (Group 1) or two 3.5 mm pelvic cortex screws (Group 2). Progressively increasing cyclic axial loading was applied through the acetabulum. Relative movements in terms of interfragmentary displacement and gap angle at the fracture site were evaluated by means of optical movement tracking. The Wilcoxon signed-rank test was applied to identify significant differences between the groups Results Initial axial construct stiffness was not significantly different between the groups (p = 0.463). Interfragmentary displacement and gap angle at the fracture site were also not statistically significantly different between the groups throughout the evaluated cycles (p ⩾ 0.249). Similarly, cycles to failure were not statistically different between Group 1 (8438, sd 6968) and Group 2 (10 213, sd 10 334), p = 0.379. Failure mode in both groups was characterised by screw cutting through the cancellous bone. Conclusion From a biomechanical point of view, pubic ramus stabilisation with either one large or two small fragment screw osteosynthesis is comparable in osteoporotic bone. However, the two-screw fixation technique is less demanding as the smaller screws deflect at the cortical margins. Cite this article: Y. P. Acklin, I. Zderic, S. Grechenig, R. G. Richards, P

  9. The efficacy of poly-d,l-lactic acid- and hyaluronic acid-coated bone substitutes on implant fixation in sheep

    Directory of Open Access Journals (Sweden)

    Christina M. Andreasen

    2017-01-01

    Conclusion: This study demonstrates that HA/βTCP granules coated with PDLLA and HyA have similar bone ingrowth and implant fixation as those with allograft, and with mechanical properties resembling those of allograft in advance, they may be considered as alternative substitute materials for bone formation in sheep.

  10. Coracoid bone graft osteolysis after Latarjet procedure: A comparison study between two screws standard technique vs mini-plate fixation

    Directory of Open Access Journals (Sweden)

    Giovanni Di Giacomo

    2013-01-01

    Full Text Available Aims: One of the reason for Latarjet procedure failure may be coracoid graft osteolysis. In this study, we aimed to understand if a better compression between the coracoid process and the glenoid, using a mini-plate fixation during the Latarjet procedure, could reduce the amount of coracoid graft osteolysis. Materials and Methods: A computed tomography scan analysis of 26 prospectively followed-up patients was conducted after modified Latarjet procedure using mini-plate fixation technique to determine both the location and the amount of coracoid graft osteolysis in them. We then compared our current results with results from that of our previous study without using mini-plate fixation to determine if there is any statistical significant difference in terms of corcacoid bone graft osteolysis between the two surgical techniques. Results: The most relevant osteolysis was represented by the superficial part of the proximal coracoid, whereas the deep part of the proximal coracoid graft is least involved in osteolysis and has best bone healing. The current study showed a significant difference only for the deep part of the distal coracoid with our previous study (P < 0.01. Discussion: To our knowledge, there are no studies in literature that show the causes of coracoid bone graft osteolysis after Latarjet procedure. Conclusion: Our study suggests that there is a significant difference only for the deep part of the distal coracoid in terms of osteolysis. At clinical examination, this difference did not correspond with any clinical findings. Level of Evidence: Level 4. Clinical Relevance: Prospective case series, Treatment study.

  11. 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

    2015-11-09

    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.

  12. Coralline hydroxyapatite granules inferior to morselized allograft around uncemented porous Ti implants: unchanged fixation by addition of concentrated autologous bone marrow aspirate.

    Science.gov (United States)

    Baas, Jorgen; Svaneby, Dea; Jensen, Thomas Bo; Elmengaard, Brian; Bechtold, Joan; Soballe, Kjeld

    2011-10-01

    We compared early fixation of titanium implants grafted with impacted allograft bone or coralline hydroxyapatite (HA) granules (Pro Osteon 200) with and without the addition of concentrated bone marrow cells (BMC). Autologous bone marrow aspirate was centrifuged to increase the BMC concentration. Four nonloaded cylindrical, porous coated titanium implants with a circumferential gap of 2.3 mm were inserted in the proximal humeri of eight dogs. Coralline HA granules +/- BMC were impacted around the two implants on one side, and allograft +/- BMC was impacted around the contra lateral implants. Observation time was 4 weeks. The implants surrounded by allograft bone had a three-fold better fixation than the HA-grafted implants. The concentration of BMC after centrifugation was increased with a factor 2.1. The addition of BMC to either of the bone graft materials had no statistically significant effects on implant fixation. The allografted implants were well osseointegrated, whereas the HA-grafted implants were largely encapsulated in fibrous tissue. The addition of concentrated autologous BMCs to the graft material had no effect on implant fixation. The HA-grafted implants were poorly anchored compared with allografted implants, suggesting that coralline HA granules should be considered a bone graft extender rather than a bone graft substitute.

  13. Osteogenic protein 1 device increases bone formation and bone graft resorption around cementless implants

    DEFF Research Database (Denmark)

    Jensen, Thomas B; Overgaard, Søren; Lind, Martin;

    2002-01-01

    In each femoral condyle of 8 Labrador dogs, a non weight-bearing hydroxyapatite-coated implant was inserted surrounded by a 3 mm gap. Each gap was filled with bone allograft or ProOsteon with or without OP-1 delivered in a bovine collagen type I carrier (OP-1 device). 300 microg OP-1 was used in ...

  14. Treatment of severe bone deficiency in acetabular revision surgery using a reinforcement device and bone grafting

    Institute of Scientific and Technical Information of China (English)

    ZHAI Ji-liang; LIN Jin; JIN Jin; QIAN Wen-wei; WENG Xi-sheng

    2011-01-01

    Background Severe acetabular bone deficiency is a major challenge in acetabular revision surgery. Most cases require reconstruction of the acetabulum with bone grafting and a reinforcement device. The purpose of this study was to evaluate the results of this procedure for severe acetabular bone deficiency in acetabular revision surgery.Methods This study involved 12 patients (2 males and 10 females) with severe acetabular bone defects who underwent implantation of a reinforcement device (ring or cage) and bone grafting between February 2003 and October 2008. Using the Paprosky classification, 2 cases were Paprosky ⅡC, 6 were ⅢA, and 4 were ⅢB. The mean age at the time of surgery was 63.0 years (range, 46-78 years). During revision surgery, a reinforcement ring was implanted in 6patients, and a cage in 6 patients. The clinical and radiographic results were evaluated retrospectively. The mean duration of follow-up was 37 months (range, 9-71 months).Results The average Harris Hip Score improved from 35.2 preoperatively to 82.9 at the time of the final follow-up visit.The results were excellent in 8 hips (66.7%), good in 2 (16.7%), and fair in 2 (16.7%). Osteolysis was found in 1 case, but did not worsen. Three patients had yellow wound effusion, with healing after administration of dressing changes,debridement, and antibiotics. Dislocation occurred in a 62-year-old woman. Closed reduction was performed, and dislocation did not recur. There was no evidence of intraoperative acetabular fracture, nerve injury, ectopic ossification,aseptic loosening, or infection.Conclusion Reconstruction with a reinforcement device and bone grafting is an effective approach to the treatment of acetabular bone deficiency in acetabular revision surgery, given proper indications and technique.

  15. Stability of unicortical locked fixation versus bicortical non-locked fixation for forearm fractures

    Institute of Scientific and Technical Information of China (English)

    Timothy J.Pater; Steve I Grindel; Gregory J.Schmeling; Mei Wang

    2014-01-01

    Locking plate fixation is being widely applied for fixation of forearm fractures and has many potential advantages, such as fixed angle fixation and improved construct stability, especially in osteoporotic bone. Biomechanical data comparing locking devices to commonly used Low Contact Dynamic Compression (LCDCP) plates for the fixation of forearm fractures has been lacking. The purpose of this study was to compare the fixation stability of a 3.5-mm unicortical locked plate with bicortical non-locked LCDCP plates. Six matched pairs of fresh frozen cadaveric forearms were randomly assigned to unicortical locked and bicortical unlocked groups. Non-destructive four-point bending and torsional test was performed on the ulna and radius separately, using a servohydraulic testing system to obtain construct stiffness of the intact specimens and specimens after osteotomy and plating. The specimens were then loaded to failure to test the fixation strength. The locked unicortical fixation showed significantly higher bending stiffness than the unlocked bicortical fixation, but with significantly lower stiffness and strength in torsion. Fixation strength was comparable between the two groups under bending, but significantly greater in the bicortical non-locked group under torsion. Findings from this study suggest that postoperative rehabilitation protocols may need modification to limit torsional loading in the early stage when using locked unicortical fixation. The study also points out the potential advantage of a hybrid fixation that combines locked unicortical and unlocked bicortical screws.

  16. CT Guided Bone Biopsy Using a Battery Powered Intraosseous Device

    Energy Technology Data Exchange (ETDEWEB)

    Schnapauff, Dirk, E-mail: dirk.schnapauff@charite.de; Marnitz, Tim, E-mail: tim.marnitz@charite.de; Freyhardt, Patrick, E-mail: Patrick.freyhardt@charite.de; Collettini, Federico, E-mail: Federico.collettini@charite.de [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Department of Radiology (Germany); Hartwig, Kerstin, E-mail: kerstin.hartwig@charite.de [Charite Universitaetsmedizin Berlin, Campus Charite Mitte, Department of Haematology and Oncology (Germany); Joehrens, Korinna, E-mail: korinna.joehrens@charite.de [Charite Universitaetsmedizin Berlin, Campus Charite Mitte, Department of Pathology (Germany); Hamm, Bernd, E-mail: bernd.hamm@charite.de; Kroencke, Thomas, E-mail: thomas.kroencke@charite.de; Gebauer, Bernhard, E-mail: Bernhard.gebauer@charite.de [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Department of Radiology (Germany)

    2013-10-15

    Purpose: To evaluate the feasibility of a battery powered intraosseous device to perform CT-fluoroscopy guided bone biopsy. Methods: Retrospective analysis of 12 patients in whom bone specimen were acquired from different locations under CT-fluoroscopy guidance using the OnControl bone marrow biopsy system (OBM, Vidacare, Shavano Park, TX, USA). Data of the 12 were compared to a historic cohort in whom the specimen were acquired using the classic Jamshidi Needle, as reference needle using manual force for biopsy. Results: Technical success was reached in 11 of 12 cases, indicated by central localisation of the needle within the target lesion. All specimen sampled were sufficient for histopathological workup. Compared to the historical cohort the time needed for biopsy decreased significantly from 13 {+-} 6 to 6 {+-} 4 min (P = 0.0001). Due to the shortened intervention time the radiation dose (CTDI) during CT-fluoroscopy was lowered significantly from 169 {+-} 87 to 111 {+-} 54 mGy Multiplication-Sign cm (P = 0.0001). Interventional radiologists were confident with the performance of the needle especially when using in sclerotic or osteoblastic lesions. Conclusion: The OBM is an attractive support for CT-fluoroscopy guided bone biopsy which is safe tool and compared to the classical approach using the Jamshidi needle leading to significantly reduced intervention time and radiation exposure.

  17. A Comparative Finite-Element Analysis of Bone Failure and Load Transfer of Osseointegrated Prostheses Fixations

    NARCIS (Netherlands)

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

    2010-01-01

    An alternative solution to conventional stump-socket prosthetic limb attachment is offered by direct skeletal fixation. This study aimed to assess two percutaneous trans-femoral implants, the OPRA system (Integrum AB, Goteborg, Sweden), and the ISP Endo/Exo prosthesis (ESKA Implants AG, Lubeck, Germ

  18. A comparative finite-element analysis of bone failure and load transfer of osseointegrated prostheses fixations.

    NARCIS (Netherlands)

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

    2010-01-01

    An alternative solution to conventional stump-socket prosthetic limb attachment is offered by direct skeletal fixation. This study aimed to assess two percutaneous trans-femoral implants, the OPRA system (Integrum AB, Goteborg, Sweden), and the ISP Endo/Exo prosthesis (ESKA Implants AG, Lubeck, Germ

  19. Historical background of bone conduction hearing devices and bone conduction hearing aids.

    Science.gov (United States)

    Mudry, Albert; Tjellström, Anders

    2011-01-01

    During the last 20 years, bone-anchored hearing aids (Baha(®)) became a familiar solution in the treatment of some types of hearing loss. The aim of this chapter is to present the different historical steps which have permitted the production of this new bone conduction hearing device. The recognition of bone conduction hearing is old and was known at least in Antiquity. During the Renaissance, Girolamo Cardano demonstrated a method by which sound may be transmitted to the ear by means of a rod or the shaft of a spear held between one's teeth: this was the beginning of teeth stimulators to improve hearing, firstly in connection with a musical instrument and then, in the second part of the 19th century, with the speaker. The development of the carbon microphone at the beginning of the 20th century allowed the construction of the bone conduction vibrator placed on the mastoid area, notably supported by eyeglasses since the 1950s. Confronted by various problems, and notably the loss of part of sound in the soft tissue of the external mastoid, the idea to implant the vibrator into the mastoid bone was developed in Göteborg, and the first Baha was implanted in 1977 by Anders Tjellström. From that date, various improvements allowed the development of the actual Baha. These different steps are presented in this study, supported by original documentation.

  20. Primary fixation and delayed nailing of long bone fractures in severe trauma

    DEFF Research Database (Denmark)

    Friedl, H.P.; Stoker, R.; Czermak, B.

    1996-01-01

    Shaft fractures of the femur or tibia or both are frequent components of multiple trauma. Besides the local fracture impact, they induce considerable systemic distress to remote organs because of pain, blood loss, necrotic or hypoperfused tissues, and mediator release. Additionally, unstable......, and the biomechanically best fixation technique should not be used, in favor of alternative procedures with a lower systemic distress level. We describe a treatment algorithm that appeared to be successful in a number of multitrauma situations....

  1. Biomechanical Evaluation of Different Fixation Methods for Mandibular Anterior Segmental Osteotomy Using Finite Element Analysis, Part Two: Superior Repositioning Surgery With Bone Allograft.

    Science.gov (United States)

    Kilinç, Yeliz; Erkmen, Erkan; Kurt, Ahmet

    2016-01-01

    In this study, the biomechanical behavior of different fixation methods used to fix the mandibular anterior segment following various amounts of superior repositioning was evaluated by using Finite Element Analysis (FEA). The three-dimensional finite element models representing 3 and 5 mm superior repositioning were generated. The gap in between segments was assumed to be filled by block bone allograft and resignated to be in perfect contact with the mandible and segmented bone. Six different finite element models with 2 distinct mobilization rate including 3 different fixation configurations, double right L (DRL), double left L (DLL), or double I (DI) miniplates with monocortical screws, correspondingly were created. A comparative evaluation has been made under vertical, horizontal and oblique loads. The von Mises and principal maximum stress (Pmax) values were calculated by finite element solver programme. The first part of our ongoing Finite Element Analysis research has been addressed to the mechanical behavior of the same fixation configurations in nongrafted models. In comparison with the findings of the first part of the study, it was concluded that bone graft offers superior mechanical stability without any limitation of mobilization and less stress on the fixative appliances as well as in the bone.

  2. 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

    Background and purpose - Internal fixation (IF) in femoral neck fractures has high reoperation rates and some predictors of failure are known, such as age, quality of reduction, and implant positioning. Finding new predictors of failure is an ongoing process, and in this study we evaluated...... the importance of low bone mineral density (BMD). Patients and methods - 140 consecutive patients (105 females, median age 80) treated with IF had a dual-energy X-ray absorptiometry (DXA) scan of the hip performed median 80 days after treatment. The patients' radiographs were evaluated for fracture displacement......, or 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...

  3. Fixation of metatarsal fracture with bone plate in a dromedary heifer

    Directory of Open Access Journals (Sweden)

    S. Hashmi

    2013-03-01

    Full Text Available An oblique fracture of the distal third of the right metatarsus in a three-year-old dromedary heifer weighing about 300 kilograms was immobilized with a 4.5 mm broad-webbed 12-hole dynamic compression bone plate and two interfragmental compression screws. The animal showed slight lameness after 16 weeks of surgery that disappeared after removal of the plate. The result was quite encouraging and the fracture healed in 16 weeks without major complications. It is concluded that the fracture of this bone can be successfully handled with bone plating at least in young, light weight animals.

  4. Transient and residual stresses and displacements in self-curing bone cement - Part II: thermoelastic analysis of the stem fixation system.

    Science.gov (United States)

    Ahmed, A M; Nair, R; Burke, D L; Miller, J

    1982-02-01

    In this second part of a two-part report, an idealized model of the stem fixation system is analyzed to determine the adverse effects of the thermal stresses and displacements of bone cement during its curing process. The Shaffer-Levitsky stress-rate strain-rate law for chemically hardening material has been used. The results show that if the cement is surrounded by cancellous bone, as opposed to cortical bone, then transient tensile circumferential stresses in the cement and similar radial stresses at the stem/cement interface are generated. The former may cause flaws and voids within the still cement, while the latter may cause gaps at the interface.

  5. A CLINICAL STUDY OF MANAGEMENT OF FRACTURE BOTH BONES FOREARM WITH INTERNAL FIXATION BY TWO DIFFERENT METHODS

    Directory of Open Access Journals (Sweden)

    Venkateswara Rao

    2015-09-01

    Full Text Available BACKGROUND AND OBJECTIVES: 60 cases of fracture both bone forearm in adults were operated and fixed using two different instruments in Siddhartha Medical College/Government General Hospital, Vijayawada between May 2013 to April 2015. METHODS: Most of the cases were young adult male with age ranging between 20 - 75yrs. The functional outcome of two different modalities of surgical management of diaphyseal fracture of both bone forearm in adults are interpreted. 30 patients were operated with DCP, and 30 patients were operated with intramedullary nailing. RESULTS : By Anderson Scoring System out of 30 cases of DCP 66.67% were excellent, 33.33% were satisfactory. Out of 30 cases of Intramedullary nailing with Talwalker square nails 50% were excellent, 23.33% were satisfactory, 16.67% were unsatisfactory, 10% had failure results. CONCLUSION : Open reduction and internal fixation can be considered as the treatment of choice if there were no contraindications for this because it is important to maintain length, opposition, axial alignment and rotational alignment if a good range of movement of forearm is to be restored. This is achieved in the present study.

  6. TREATMENT OF CLOSED TIBIAL PILON FRACTURES WITH OPEN REDUCTION, INTERNAL FIXATION AND BONE GRAFTING. A STUDY OF 22 CASES COMPARING THE OBJE CTIVE AND SUBJECTIVE EVALUATION

    Directory of Open Access Journals (Sweden)

    Athmaram

    2015-02-01

    Full Text Available The cases of twenty two fractures of the ankle joint that involved the tibial plafond were reviewed. The fractures were classified in to five types according to the severity of the injury. Open reduction and internal fixation was performed using one third tubular plate for fibula and recon plate for the tibia. Bone grafting was don e to augment the fixation and maintain the reduction . For each fracture treated Objective and Subjective evaluation is done. The objective and subjective scores are compared. With this method we noticed that the Type III & IV fractures also had a good or e xcellent result .

  7. In vivo study of extracellular matrix coating enhancing fixation of the pedicle screw-bone's interface

    Institute of Scientific and Technical Information of China (English)

    LIU Guo-min; ZHANG Xing-yi; XU Chuan-jie; ZHU Xiao-min; WANG Jun; LIU Yi

    2011-01-01

    Background Based on in vivo research on the effect of the coating of the extracellular matrix composition of pedicle screws on the conduction and induction of bone formation in young sheep,the aim of this study was to investigate the application of coated pedicle screws in sheep with scoliosis whose spines are under constant development.Methods Four groups of pedicle screws were randomly implanted into bilateral L2-L5 pedicles of 2.5- to 3-month-old sheep.A static experiment was performed on one side and a loading test was performed on the other side by implanting connecting rods at the L2-L3 and L4-L5 segments.The changes in the force on the coated screws and the combination of the surface of the coated screws with the surrounding bone in the growth process of young sheep's spines with aging were observed.After 3 months,the lumbar vertebrae with the screws were removed and examined by micro-CT,histological,and biomechanical analyses.Results Under nonloading conditions,there is bone formation around the surfaces of coated screws.The bone forming on the surface of collagen/chondroitin sulfate/hydroxyapatite coating of pedicle screws is the most,the one of the collagen / chondrcitin sulfate coating and hydroxyapatite coating is followed,and no significant difference between the two groups.In terms of the trabecular bone morphology parameters of the region of interest around the surface of the pedicle screws,such as bone mineral content,bone mineral density,tissue mineral content,tissue bone mineral density,bone volume fraction,and connection density,those associated with collagen/chondroitin sulfate/hydroxyapatite coatings are largest and those unassociated with coatings are smallest.Under nonloading conditions,the pullout strength of the collagen/chondroitin sulfate/hydroxyapatite-coated screws was largest,and that of the uncoated screws was minimal (P <0.01).Under loading conditions,the maximum pullout strength of each group of pedicle screws was less than that

  8. Modifying bone scaffold architecture in vivo with permanent magnets to facilitate fixation of magnetic scaffolds.

    Science.gov (United States)

    Panseri, S; Russo, A; Sartori, M; Giavaresi, G; Sandri, M; Fini, M; Maltarello, M C; Shelyakova, T; Ortolani, A; Visani, A; Dediu, V; Tampieri, A; Marcacci, M

    2013-10-01

    The fundamental elements of tissue regeneration are cells, biochemical signals and the three-dimensional microenvironment. In the described approach, biomineralized-collagen biomaterial functions as a scaffold and provides biochemical stimuli for tissue regeneration. In addition superparamagnetic nanoparticles were used to magnetize the biomaterials with direct nucleation on collagen fibres or impregnation techniques. Minimally invasive surgery was performed on 12 rabbits to implant cylindrical NdFeB magnets in close proximity to magnetic scaffolds within the lateral condyles of the distal femoral epiphyses. Under this static magnetic field we demonstrated, for the first time in vivo, that the ability to modify the scaffold architecture could influence tissue regeneration obtaining a well-ordered tissue. Moreover, the association between NdFeB magnet and magnetic scaffolds represents a potential technique to ensure scaffold fixation avoiding micromotion at the tissue/biomaterial interface.

  9. Quantifying the Effects of Formalin Fixation on the Mechanical Properties of Cortical Bone Using Beam Theory and Optimization Methodology With Specimen-Specific Finite Element Models.

    Science.gov (United States)

    Zhang, Guan-Jun; Yang, Jie; Guan, Feng-Jiao; Chen, Dan; Li, Na; Cao, Libo; Mao, Haojie

    2016-09-01

    The effects of formalin fixation on bone material properties remain debatable. In this study, we collected 36 fresh-frozen cuboid-shaped cortical specimens from five male bovine femurs and immersed half of the specimens into 4% formalin fixation liquid for 30 days. We then conducted three-point bending tests and used both beam theory method and an optimization method combined with specimen-specific finite element (FE) models to identify material parameters. Through the optimization FE method, the formalin-fixed bones showed a significantly lower Young's modulus (-12%) compared to the fresh-frozen specimens, while no difference was observed using the beam theory method. Meanwhile, both the optimization FE and beam theory methods revealed higher effective failure strains for formalin-fixed bones compared to fresh-frozen ones (52% higher through the optimization FE method and 84% higher through the beam theory method). Hence, we conclude that the formalin fixation has a significant effect on bovine cortical bones at small, elastic, as well as large, plastic deformations.

  10. Guided bone augmentation using ceramic space-maintaining devices: the impact of chemistry

    Science.gov (United States)

    Anderud, Jonas; Abrahamsson, Peter; Jimbo, Ryo; Isaksson, Sten; Adolfsson, Erik; Malmström, Johan; Naito, Yoshihito; Wennerberg, Ann

    2015-01-01

    The purpose of the study was to evaluate histologically, whether vertical bone augmentation can be achieved using a hollow ceramic space maintaining device in a rabbit calvaria model. Furthermore, the chemistry of microporous hydroxyapatite and zirconia were tested to determine which of these two ceramics are most suitable for guided bone generation. 24 hollow domes in two different ceramic materials were placed subperiosteal on rabbit skull bone. The rabbits were sacrificed after 12 weeks and the histology results were analyzed regarding bone-to-material contact and volume of newly formed bone. The results suggest that the effect of the microporous structure of hydroxyapatite seems to facilitate for the bone cells to adhere to the material and that zirconia enhance a slightly larger volume of newly formed bone. In conclusion, the results of the current study demonstrated that ceramic space maintaining devices permits new bone formation and osteoconduction within the dome. PMID:25792855

  11. Do Bone Graft and Cracking of the Sclerotic Cavity Improve Fixation of Titanium and Hydroxyapatite-coated Revision Implants in an Animal Model?

    DEFF Research Database (Denmark)

    Elmengaard, Brian; Baas, Joergen; Jakobsen, Thomas;

    2016-01-01

    (crack, noncrack) using paired contralateral implants while implant surface (Ti6Al4V, HA) was qualitatively compared between the two (unpaired) series. All groups received bone allograft tightly packed around the implant. This revision model includes a cylindrical implant pistoning 500 μm in a 0.75-mm...... gap, with polyethylene particles, for 8 weeks. This engenders a bone and tissue response representative of the metaphyseal cancellous region of an aseptically loosened component. At 8 weeks, the original implants were revised and followed for an additional 4 weeks. Mechanical fixation was assessed...

  12. 骨外固定治疗复杂骨不连与骨缺损的临床效果%External Fixation for the Treatment of Complex Bone Nonunion and Bone Defect of Clinical effect

    Institute of Scientific and Technical Information of China (English)

    徐占辉

    2015-01-01

    目的:探讨骨外固定治疗复杂骨不连及骨缺损临床效果。方法对56例患者采用骨外固定技术治疗复复杂骨不连与骨缺损的效果进行分析。结果56例骨不连与骨缺损患者均实现骨性愈合。17例感染性骨不连患者的伤口得到有效控制。非感染性骨不连患者一般需要4个月左右的时间愈合,感染性骨不连患者一般需要6个月左右的时间愈合,患者重建肢体长度后肢体长度均衡。结论采用骨外固定技术治疗骨不连患者可获得令人满意的疗效。%Objective To study the bone external fixation in treatment of complex bone nonunion and bone defect of clinical effects.Methods colecting effect were treated byexternal fixation for treatment of bone nonunion in 56 cases were analyzed.Results 56 cases of nonunion patients achieved bone healing.Not even the patient's wound infection has been effectively controled in 17 cases of infected bone.The healing of non infectious nonunion Bone patients generaly need 5 months time,healing of infected nonunion Bone patients generaly need about 6 months time,reconstruction in limb length after limb length equalization.Conclusion The use of external fixation for treatment of nonunion has obtained the satisfactory effect.

  13. An application of principal component analysis to the clavicle and clavicle fixation devices.

    LENUS (Irish Health Repository)

    Daruwalla, Zubin J

    2010-01-01

    Principal component analysis (PCA) enables the building of statistical shape models of bones and joints. This has been used in conjunction with computer assisted surgery in the past. However, PCA of the clavicle has not been performed. Using PCA, we present a novel method that examines the major modes of size and three-dimensional shape variation in male and female clavicles and suggests a method of grouping the clavicle into size and shape categories.

  14. Surgical Revision after Sacroiliac Joint Fixation or Fusion

    Science.gov (United States)

    Holt, Timothy

    2017-01-01

    Background Minimally invasive sacroiliac joint (SIJ) fusion has been shown to be safe and effective for the treatment of SIJ dysfunction. Multiple devices are available to perform SIJ fixation or fusion. Surgical revision rates after these procedures have not been directly compared. Methods We retrospectively identified all patients in our practice who underwent SIJ fixation or fusion between 2003 and 2015. Using both chart review and focused contact with individual patients, we determined the likelihood of surgical revision. Revision rates were compared using Kaplan-Meier survival analysis. Results Thirty-eight patients underwent SIJ fixation with screws and 274 patients underwent SIJ fusion using triangular titanium implants. Four-year cumulative revision rates were 30.8% for fixation and 5.7% for fusion. Conclusions In our study, SIJ fixation with screws had a much higher revision rate compared to SIJ fusion with triangular titanium implants designed for bone adherence.

  15. 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.

  16. 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.

  17. 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.

  18. Clinical results of reversed V-shaped high tibial corticotomy with minimally invasive surgery without internal fixation devices.

    Science.gov (United States)

    Madadi, Firooz; Eajazi, Alireza; Madadi, Firoozeh; Daftari Besheli, Laleh; Rokni, Reza; Abbasian, Mohammad Reza; Bigdeli, Mohammad Reza

    2010-06-09

    High tibial osteotomy is a method of treating knee osteoarthritis due to genu varum in advanced stages. High tibial osteotomy-associated problems continue to be reported. The purpose of this study was to investigate the clinical results of a new, innovative method of high tibial osteotomy with 3- to 13-year follow-up. Between 1996 and 2006, our new surgical method was performed on 293 patients with medial compartment osteoarthritis and genu varum. All patients were examined preoperatively, 6 months postoperatively, and at final follow-up. The Hospital for Special Surgery Knee Scoring System (HSS) was used at final follow-up, and limb alignment and patient satisfaction were reassessed. Immediate postoperative complications included varus recurrence, knee instability, and peroneal nerve palsy, and no signs of tibial nonunion or infection were observed. At final follow-up, 3 cases of genu recurvatum, 2 cases of peroneal nerve palsy, and 25 cases of loss of correction were observed. Average postoperative HSS score was 85 (range, 47-97), and 97.8% of the patients were satisfied. This new method is a good alternative for the correction of genu varum because it requires a small incision, is soft tissue friendly, is a corticotomy instead of an osteotomy, requires no internal or external fixation devices, has a shorter duration and an acceptable complication and recurrence rate, and results in satisfactory HSS scores and higher patient satisfaction rates.

  19. Validation of a finite element model of a unilateral external fixator in a rabbit tibia defect model.

    Science.gov (United States)

    Karunratanakul, Kavin; Kerckhofs, Greet; Lammens, Johan; Vanlauwe, Johan; Schrooten, Jan; Van Oosterwyck, Hans

    2013-07-01

    In case of large segmental defects in load-bearing bones, an external fixator is used to provide mechanical stability to the defect site. The overall stiffness of the bone-fixator system is determined not only by the fixator design but also by the way the fixator is mounted to the bone. This stiffness is an important factor as it will influence the biomechanical environment to which tissue engineering scaffolds and regenerating tissues are exposed. A finite element (FE) model can be used to predict the system stiffness. The goal of this study is to develop and validate a 3D anatomical FE model of a bone-fixator system which includes a previously developed unilateral external fixator for a large segmental defect model in the rabbit tibia. It was hypothesized that the contact interfaces between bone and fixator screws play a major role for the prediction of the stiffness. In vitro mechanical testing was performed in order to measure the axial stiffness of cortical bone from mid-shaft rabbit tibiae and of the tibia-fixator system, as well as the bending stiffness of individual fixator screws, inserted in bone. μCT-based case-specific FE models of cortical bone and SCREW-BONE specimens were created to simulate the corresponding mechanical test set-ups. The Young's modulus of rabbit cortical bone as well as appropriate screw-bone contact settings were derived from those FE models. We then used the derived settings in an FE model of the tibia-fixator system. The difference between the FE predicted and measured axial stiffness of the tibia-fixator system was reduced from 117.93% to 7.85% by applying appropriate screw-bone contact settings. In conclusion, this study shows the importance of screw-bone contact settings for an accurate fixator stiffness prediction. The validated FE model can further be used as a tool for virtual mechanical testing in the design phase of new tissue engineering scaffolds and/or novel patient-specific external fixation devices.

  20. Guided bone augmentation using ceramic space-maintaining devices: the impact of chemistry

    Directory of Open Access Journals (Sweden)

    Anderud J

    2015-03-01

    Full Text Available Jonas Anderud,1,2 Peter Abrahamsson,2 Ryo Jimbo,1 Sten Isaksson,2 Erik Adolfsson,3 Johan Malmström,2 Yoshihito Naito,4 Ann Wennerberg1 1Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden; 2Maxillofacial Unit Halmstad, Region Halland, Halmstad, Sweden; 3Swedish Ceramic Institute, IVF, Mölndal, Sweden; 4Department of Oral and Maxillofacial Prosthodontics and Oral Implantology, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan Abstract: The purpose of the study was to evaluate histologically, whether vertical bone augmentation can be achieved using a hollow ceramic space maintaining device in a rabbit calvaria model. Furthermore, the chemistry of microporous hydroxyapatite and zirconia were tested to determine which of these two ceramics are most suitable for guided bone generation. 24 hollow domes in two different ceramic materials were placed subperiosteal on rabbit skull bone. The rabbits were sacrificed after 12 weeks and the histology results were analyzed regarding bone-to-material contact and volume of newly formed bone. The results suggest that the effect of the microporous structure of hydroxyapatite seems to facilitate for the bone cells to adhere to the material and that zirconia enhance a slightly larger volume of newly formed bone. In conclusion, the results of the current study demonstrated that ceramic space maintaining devices permits new bone formation and osteoconduction within the dome. Keywords: hydroxyapatite, zirconia, guided bone regeneration, GBR, histology, membrane

  1. Observation of Clinical Nursing Self-locking Gastric Tube Fixation Device%自锁式胃管固定器的临床护理观察

    Institute of Scientific and Technical Information of China (English)

    樊玲; 吴李莉

    2012-01-01

    Objective: To observe the effect and adverse reaction of nursing self-locking gastric tube fixation device. Methods: Patients were randomly divided into test group (whose Gastric Tube were fixed by self-locking gastric tube fixation device) and control group (whose gastric tube were fixed by routine rubberized fabric. The course of treatment was 1 ~2 weeks. Results: The effect and adverse reaction of test group was better than that of control group. Conclusions: Self-locking gastric tube fixation device has good effect and safety.%目的 观察自锁式胃管固定器对胃管固定的有效性和不良反应.方法 将患者随机分为试验组(自锁式胃管固定器固定胃管)和对照组(常规胶布固定胃管),观察时间为1~2周.结果 试验组固定胃管的有效性和不良反应方面均优于对照组的.结论 自锁式胃管固定器固定胃管有效且安全.

  2. 可吸收固定系统在开颅骨瓣复位固定手术中的初步应用%PRELIMINARY APPLICATION OF ABSORBABLE FIXATION SYSTEM ON CRANIAL BONE FLAP REPOSITION AND FIXATION AFTER CRANIOTOMY

    Institute of Scientific and Technical Information of China (English)

    邓跃飞; 郑眉光; 吴锦铨

    2012-01-01

    目的 观察可吸收固定系统对开颅游离骨瓣复位的固定效果及不良反应.方法 2010年7月-2011年12月,对67例开颅游离骨瓣成型切除颅内病变后患者,采用可吸收固定系统进行骨瓣复位固定.其中男38例,女29例;年龄5个月~73岁,中位年龄32岁.病程3个月~6年,中位病程25个月.幕上病变41例,幕下病变26例;其中位于额颞部13例,额顶部12例,颞顶部8例,颞枕部5例,顶枕部4例,后颅窝25例.诊断为胶质瘤15例,脑血管性疾病(动脉瘤、动静脉畸形及海绵状血管瘤)8例,脑膜瘤和蛛网膜囊肿各7例,听神经瘤和原发三叉神经痛各5例,胆脂瘤和脑脓肿各3例,垂体瘤、颅咽管瘤、转移瘤及放射性脑病各2例,髓母细胞瘤、室管膜瘤、生殖细胞瘤、非典型畸胎瘤/横纹肌样瘤、面肌痉挛及硬膜下血肿各1例.颅内病变范围3cm×2cm~7cm×5cm.观察术后局部切口及全身情况变化.结果 术后有2例幕上和3例幕下病变患者少许皮下积液,均经穿刺抽吸2周后消失;术后切口均Ⅰ期愈合,无红肿、发热等表现;术后2周内复查CT或MRI示骨瓣复位良好,内、外颅骨面均平整,无任何影像伪影.67例均获随访,随访时间3~20个月,平均10.3个月.切口无不适,头颅外观正常,无局部凹陷、积液等.CT或MRI复查未见骨瓣移位凹陷及伪影.结论 应用可吸收固定系统进行骨瓣复位固定简便、安全、可靠,且能消除术后CT或MRI复查时金属固定材料导致的伪影,近期疗效较好.%Objective To investigate the effectiveness and adverse effect of the absorbable fixation system on cranial bone flap reposition and fixation after craniotomy. Methods Between July 2010 and December 2011, 67 cases underwent cranial bone flap reposition and fixation with absorbable fixation system after craniotomy and resection of intracranial lesions. There were 38 males and 29 females with a median age of 32 years (range, 5 months to 73

  3. CT pre-operative planning of a new semi-implantable bone conduction hearing device

    Energy Technology Data Exchange (ETDEWEB)

    Law, Eric K.C.; Bhatia, Kunwar S.S. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Hong Kong, SAR (China); Tsang, Willis S.S.; Tong, Michael C.F. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Otorhinolaryngology, Head and Neck Surgery, Hong Kong, SAR (China); Shi, Lin [The Chinese University of Hong Kong, Department of Medicine and Therapeutics, Hong Kong, SAR (China); The Chinese University of Hong Kong, Chow Yuk Ho Technology Center for Innovative Medicine, Hong Kong, SAR (China)

    2016-06-15

    Accommodating a novel semi-implantable bone conduction hearing device within the temporal bone presents challenges for surgical planning. This study describes the utility of CT in pre-operative assessment of such an implant. Retrospective review of pre-operative CT, clinical and surgical records of 16 adults considered for device implantation. Radiological suitability was assessed on CT using 3D simulation software. Antero-posterior (AP) dimensions of the mastoid bone and minimum skull thickness were measured. CT planning results were correlated with operative records. Eight and five candidates were suitable for device placement in the transmastoid and retrosigmoid positions, respectively, and three were radiologically unsuitable. The mean AP diameter of the mastoid cavity was 14.6 mm for the transmastoid group and 4.6 mm for the retrosigmoid group (p < 0.05). Contracted mastoid and/or prior surgery were predisposing factors for unsuitability. Four transmastoid and five retrosigmoid positions required sigmoid sinus/dural depression and/or use of lifts due to insufficient bone capacity. A high proportion of patients being considered have contracted or operated mastoids, which reduces the feasibility of the transmastoid approach. This finding combined with the complex temporal bone geometry illustrates the importance of careful CT evaluation using 3D software for precise device simulation. (orig.)

  4. Uterine doughnut by intrauterine device-induced photon attenuation on three-phase bone scintigraphy: artifact

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Myung Hee; Jeong, Hwan Jeong; Lim, Seok Tae [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    2007-02-15

    A 44-year-old female underwent three-phase bone scintigraphy for an evaluation of right hip joint pain. The blood-flow and blood-pool images show a pelvic blush with a photopenic center (doughnut) prior to bladder filling. On the three hour delayed image, the pelvic uptake disappeared. The scintigraphic findings indicated the possibility of an early pregnancy. However, plain radiography demonstrated an intrauterine device. A uterine doughnut developed as a result of photon attenuation of intrauterine device.

  5. Efficacy and safety of biodegradable osteofixation devices in oral and maxillofacial surgery : a systematic review

    NARCIS (Netherlands)

    Buijs, G. J.; Stegenga, B.; Bos, R. R. M.

    2006-01-01

    The use of osteofixation devices should be evidence-based if uncomplicated bone healing is to be achieved. Numerous studies describe and claim the advantages of biodegradable over titanium devices as a bone fixation method. Here, we systematically review the available literature to determine the cli

  6. Review: Bone conduction devices and contralateral routing of sound systems in single-sided deafness

    NARCIS (Netherlands)

    Peters, Jeroen P M; Smit, Adriana L; Stegeman, Inge; Grolman, Wilko

    2015-01-01

    OBJECTIVES/HYPOTHESIS: Systematically review the literature on the clinical outcome of bone conduction devices (BCD) and contralateral routing of sound systems (CROSS) for patients with single-sided deafness (SSD). DATA SOURCES: PubMed, Embase, Cochrane Library, and CINAHL databases were searched up

  7. The application of closed reduction internal fixation and iliac bone block grafting in the treatment of acute displaced femoral neck fractures.

    Directory of Open Access Journals (Sweden)

    Zhiyong Li

    Full Text Available OBJECTIVE: This study aimed to evaluate the preliminary clinical and radiographic outcomes of acute displaced femoral neck fracture treated by closed reduction and internal fixation (CRIF with free iliac bone block grafting with comparison to a routine protocol of CRIF without bone grafting. METHODS: From December 2008 to February 2010, 220 adult patients with acute displaced femoral neck fractures were enrolled in this study. In study group, there were 124 patients (57 males, 67 females with a mean age of 44.8 years (range, 20-64 years. There were 70 transcervical fractures and 54 subcapital fractures. The patients were treated by CRIF and free iliac bone block grafting. The control group consisted of 96 adult patients (46 males, 50 females with a mean age of 46.3 years (range, 23-64 years. There were 61 transcervical fractures and 35 subcapital fractures. The patients in control group were treated by CRIF without bone grafting. RESULTS: In study group, 112 patients were followed up for an average of 27.4 months (range, 24-34 months. All fractures healed within 5 months. However, 10 patients presented AVN of the femoral heads. The mean Harris score was 88.6 (range, 41-100. In control group, 68 patients were followed up for an average of 31.2 months (range, 24-42 months. The rates of AVN of the femoral head and fracture nonunion in control group were 26.5% (18/68 and 16.2% (11/68, respectively, significantly higher than those in study group (both P<0.05. The mean Harris score in control group was 83.8 (41-100, significantly lower than that in study group (P<0.05. CONCLUSION: Acute displaced femoral neck fractures can be treated by CRIF and free iliac bone block grafting in a minimally invasive manner. This technique can guarantee uneventful fracture healing and significantly reduce the rate of femoral head osteonecrosis.

  8. Fracture of the L-4 vertebral body after use of a stand-alone interbody fusion device in degenerative spondylolisthesis for anterior L3-4 fixation.

    Science.gov (United States)

    Kwon, Yoon-Kwang; Jang, Ju-Hee; Lee, Choon-Dae; Lee, Sang-Ho

    2014-06-01

    Many studies attest to the excellent results achieved using anterior lumbar interbody fusion (ALIF) for degenerative spondylolisthesis. The purpose of this report is to document a rare instance of L-4 vertebral body fracture following use of a stand-alone interbody fusion device for L3-4 ALIF. The patient, a 55-year-old man, had suffered intractable pain of the back, right buttock, and left leg for several weeks. Initial radiographs showed Grade I degenerative spondylolisthesis, with instability in the sagittal plane (upon 15° rotation) and stenosis of central and both lateral recesses at the L3-4 level. Anterior lumbar interbody fusion of the affected vertebrae was subsequently conducted using a stand-alone cage/plate system. Postoperatively, the severity of spondylolisthesis diminished, with resolution of symptoms. However, the patient returned 2 months later with both leg weakness and back pain. Plain radiographs and CT indicated device failure due to anterior fracture of the L-4 vertebral body, and the spondylolisthesis had recurred. At this point, bilateral facetectomies were performed, with reduction/fixation of L3-4 by pedicle screws. Again, degenerative spondylolisthesis improved postsurgically and symptoms eased, with eventual healing of the vertebral body fracture. This report documents a rare instance of L-4 vertebral body fracture following use of a stand-alone device for ALIF at L3-4, likely as a consequence of angular instability in degenerative spondylolisthesis. Under such conditions, additional pedicle screw fixation is advised.

  9. A Mechatronic Loading Device to Stimulate Bone Growth via a Human Knee

    Directory of Open Access Journals (Sweden)

    Sai Krishna Prabhala

    2016-09-01

    Full Text Available This paper presents the design of an innovative device that applies dynamic mechanical load to human knee joints. Dynamic loading is employed by applying cyclic and periodic force on a target area. The repeated force loading was considered to be an effective modality for repair and rehabilitation of long bones that are subject to ailments like fractures, osteoporosis, osteoarthritis, etc. The proposed device design builds on the knowledge gained in previous animal and mechanical studies. It employs a modified slider-crank linkage mechanism actuated by a brushless Direct Current (DC motor and provides uniform and cyclic force. The functionality of the device was simulated in a software environment and the structural integrity was analyzed using a finite element method for the prototype construction. The device is controlled by a microcontroller that is programmed to provide the desired loading force at a predetermined frequency and for a specific duration. The device was successfully tested in various experiments for its usability and full functionality. The results reveal that the device works according to the requirements of force magnitude and operational frequency. This device is considered ready to be used for a clinical study to examine whether controlled knee-loading could be an effective regimen for treating the stated bone-related ailments.

  10. The role of AO external fixation in proximal femoral osteotomies in the pediatric neuromuscular population.

    Science.gov (United States)

    Handelsman, John E; Weinberg, Jacob; Razi, Afshin; Mulley, Debra A

    2004-09-01

    Internal fixation in proximal femoral osteotomies using traditional devices may be sub-optimal in children with neuromuscular disorders who have small or osteopenic bone. In this population, between 1988 and 2000, we performed 36 proximal femoral varus osteotomies in 28 patients. These were controlled by the AO external fixator. The average age at surgery was 7 years (range, 2-13 years). A mean varus correction of 34 degrees (range, 15-90 degrees) was obtained. Complications consisted of one superficial pin tract infection, one skin breakdown, and one non-union. Other than the non-union, all osteotomies were stable at the time of the fixator removal. The AO external fixator is an effective alternative in maintaining corrective proximal femoral osteotomies in children with fragile bones.

  11. Biomechanical evaluations of three anterior thoracolumbar internal fixation devices%三种胸腰椎前路内固定器的生物力学评价

    Institute of Scientific and Technical Information of China (English)

    朱建炜; 董启榕; 朱建泉; 成红兵; 王以进

    2005-01-01

    背景:胸腰椎前路内固定器械可分为两类:一类为以Kaneda代表的钉棍系统,一类为以Z-plate等代表的钉板系统.它们均具有良好的生物力学性能,但这类器械均为国外进口,价格昂贵,国内普通患者难以承受.作者在各种胸腰椎前路钢板系统和国人脊柱解剖特点的基础上,研制出一套适合国人胸腰椎形态学特点的前路新型钛合金钢板(NTP).目的:对DunnⅢ,NTP,Z-plate等3种前路内固定器生物力学进行比较,为临床应用提供科学的理论依据.设计:抽样调查.单位:苏州大学附属第二医院骨科和南通市虹桥医院放射科.对象:实验于2003-05/08在上海大学生物力学工程研究所完成.选择15具健康成年人体新鲜脊柱标本.方法:采用新鲜成人胸腰椎标本(T12~S1)15具,制成前、中柱损伤模型,分别以DunnⅢ、NTP、Z-plate固定,进行强度、刚度和稳定性的研究.主要观察指标:测量3组标本在轴向压缩、前屈、后伸、侧屈等4种工况下的载荷-应变变化,载荷-位移变化.结果:15具成年人体新鲜脊柱标本,均进入结果分析.在最大载荷500N下,Z-plate平均应变最小为410 uε,NTP平均应变其次为430 uε,而Dunn平均应变最大477 uε;脊柱的平均纵向位移,Z-plate组最小为2.23 mm,NTP组为2.38 mm,而Dunn组的平均纵向位移为2.85mm.胸腰椎骨折采用三种前路内固定器固定后,在脊柱的强度、刚度和稳定性方面,NTP、Z-plate均优于DunnⅢ(P<0.05),而NTP和Z-plate差异无显著性意义(P>0.05).结论:NTP和Z-plate系统符合脊柱的生物力学,能有效恢复失稳脊柱的稳定性,是较为理想的前路内固定器.%BACKGROUND: The anterior thoracolumbar internal fixation devices can be divided into two main categories: the stick system such as kaneda,and the plate system such as Z-plate. Both categories have satisfactory biomechanical properties, but the devices of these types are all imported and so

  12. Latarjet Fixation

    Science.gov (United States)

    Alvi, Hasham M.; Monroe, Emily J.; Muriuki, Muturi; Verma, Rajat N.; Marra, Guido; Saltzman, Matthew D.

    2016-01-01

    Background: Attritional bone loss in patients with recurrent anterior instability has successfully been treated with a bone block procedure such as the Latarjet. It has not been previously demonstrated whether cortical or cancellous screws are superior when used for this procedure. Purpose: To assess the strength of stainless steel cortical screws versus stainless steel cannulated cancellous screws in the Latarjet procedure. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen matched-pair shoulder specimens were randomized into 2 separate fixation groups: (1) 3.5-mm stainless steel cortical screws and (2) 4.0-mm stainless steel partially threaded cannulated cancellous screws. Shoulder specimens were dissected free of all soft tissue and a 25% glenoid defect was created. The coracoid process was osteomized, placed at the site of the glenoid defect, and fixed in place with 2 parallel screws. Results: All 10 specimens failed by screw cutout. Nine of 10 specimens failed by progressive displacement with an increased number of cycles. One specimen in the 4.0-mm screw group failed by catastrophic failure on initiation of the testing protocol. The 3.5-mm screws had a mean of 274 cycles (SD, ±171 cycles; range, 10-443 cycles) to failure. The 4.0-mm screws had a mean of 135 cycles (SD, ±141 cycles; range, 0-284 cycles) to failure. There was no statistically significant difference between the 2 types of screws for cycles required to cause failure (P = .144). Conclusion: There was no statistically significant difference in energy or cycles to failure when comparing the stainless steel cortical screws versus partially threaded cannulated cancellous screws. Clinical Relevance: Latarjet may be performed using cortical or cancellous screws without a clear advantage of either option. PMID:27158630

  13. 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

  14. Excision of extensive midfoot pigmented villonodular synovitis with microvascular anastamosis of iliac crest bone graft using external fixation: a case report.

    Science.gov (United States)

    Oloff, Lawrence; Miller, Kevin

    2011-10-01

    Pigmented villonodular synovitis (PVNS) is a relatively rare lesion in the foot and ankle, most commonly involving the ankle joint and atypically, the subtalar and midtarsal joints. It is a benign proliferative disease characterized by an increase in villous or nodular synovium in joints. Resection of the tumor is often indicated in most cases because of the potentially aggressive joint destructive nature of this lesion. This report presents a case of chronic enlarging pervasive midtarsal and metatarsal-cuneiform joint PVNS in a 28-year-old male. This patient had a midtarsal mass that enlarged over a period of 2 years, causing increased pain, deformity, and difficulty with ambulation. Cross-sectional imaging studies identified evidence of erosive disease through much of the midfoot articulations, with biopsy confirming the mass as PVNS. The dimensions of the mass approximated 5.5 cm × 4.1 cm × 2.8 cm. Simple resection was problematic because of the size and multiple joints involved. Amputation was most commonly advised by multiple consultants. The patient preferred attempt at limb salvage. En bloc resection and placement of a revascularized iliac crest bone graft was used to fill the defect. The graft was microvascularly anastamosed and fixated with standard external fixation. Pathologic and histologic specimens from surgical biopsy reconfirmed the diagnosis of PVNS postoperatively. Second-stage arthrodesis was performed when the patient was stable and disease free. The patient was followed postoperatively for 10 years without recurrence and was able to return to full function and partake in moderate athletic activity at last visit. This case describes a retrospective review of the procedure and reconstruction, as well as an overview of current surgical management of PVNS.

  15. 21 CFR 872.4880 - Intraosseous fixation screw or wire.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraosseous fixation screw or wire. 872.4880... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4880 Intraosseous fixation screw or wire. (a) Identification. An intraosseous fixation screw or wire is a metal device intended to be...

  16. Preliminary experience with biodegradable implants for fracture fixation

    Directory of Open Access Journals (Sweden)

    Dhillon Mandeep

    2008-01-01

    Full Text Available Background: Biodegradable implants were designed to overcome the disadvantages of metal-based internal fixation devices. Although they have been in use for four decades internationally, many surgeons in India continue to be skeptical about the mechanical strength of biodegradable implants, hence this study. Materials and Methods: A prospective study was done to assess the feasibility and surgeon confidence level with biodegradable implants over a 12-month period in an Indian hospital. Fifteen fractures (intra-articular, metaphyseal or small bone fractures were fixed with biodegradable implants. The surgeries were randomly scheduled so that different surgeons with different levels of experience could use the implants for fixation. Results: Three fractures (one humeral condyle, two capitulum, were supplemented by additional K-wires fixation. Trans-articular fixator was applied in two distal radius and two pilon fractures where bio-pins alone were used. All fractures united, but in two cases the fracture displaced partially during the healing phase; one fibula due to early walking, and one radius was deemed unstable even after bio-pin and external fixator. Conclusions: Biodegradable -implants are excellent for carefully selected cases of intra-articular fractures and some small bone fractures. However, limitations for use in long bone fractures persist and no great advantage is gained if a "hybrid" composite is employed. The mechanical properties of biopins and screws in isolation are perceived to be inferior to those of conventional metal implants, leading to low confidence levels regarding the stability of reduced fractures; these implants should be used predominantly in fracture patterns in which internal fixation is subjected to minimal stress.

  17. Anodizing color coded anodized Ti6Al4V medical devices for increasing bone cell functions.

    Science.gov (United States)

    Ross, Alexandra P; Webster, Thomas J

    2013-01-01

    Current titanium-based implants are often anodized in sulfuric acid (H(2)SO(4)) for color coding purposes. However, a crucial parameter in selecting the material for an orthopedic implant is the degree to which it will integrate into the surrounding bone. Loosening at the bone-implant interface can cause catastrophic failure when motion occurs between the implant and the surrounding bone. Recently, a different anodization process using hydrofluoric acid has been shown to increase bone growth on commercially pure titanium and titanium alloys through the creation of nanotubes. The objective of this study was to compare, for the first time, the influence of anodizing a titanium alloy medical device in sulfuric acid for color coding purposes, as is done in the orthopedic implant industry, followed by anodizing the device in hydrofluoric acid to implement nanotubes. Specifically, Ti6Al4V model implant samples were anodized first with sulfuric acid to create color-coding features, and then with hydrofluoric acid to implement surface features to enhance osteoblast functions. The material surfaces were characterized by visual inspection, scanning electron microscopy, contact angle measurements, and energy dispersive spectroscopy. Human osteoblasts were seeded onto the samples for a series of time points and were measured for adhesion and proliferation. After 1 and 2 weeks, the levels of alkaline phosphatase activity and calcium deposition were measured to assess the long-term differentiation of osteoblasts into the calcium depositing cells. The results showed that anodizing in hydrofluoric acid after anodizing in sulfuric acid partially retains color coding and creates unique surface features to increase osteoblast adhesion, proliferation, alkaline phosphatase activity, and calcium deposition. In this manner, this study provides a viable method to anodize an already color coded, anodized titanium alloy to potentially increase bone growth for numerous implant applications.

  18. Functionality Evaluation of a Novel Smart Expandable Pedicle Screw to Mitigate Osteoporosis Effect in Bone Fixation: Modeling and Experimentation

    Directory of Open Access Journals (Sweden)

    Ahmadreza Eshghinejad

    2013-01-01

    Full Text Available This paper proposes a novel expandable-retractable pedicle screw and analyzes its functionality. A specially designed pedicle screw is described which has the ability to expand and retract using nitinol elements. The screw is designed to expand in body temperature and retract by cooling the screw. This expansion-retraction function is verified in an experiment designed in larger scale using a nitinol antagonistic assembly. The results of this experiment are compared to the results of a finite element model developed in Abaqus in combination with a user material subroutine (UMAT. This code has been developed to analyze the nonlinear thermomechanical behavior of shape memory alloy materials. The functionality of the proposed screw is evaluated with simulation and experimentation in a pullout test as well. The pullout force of a normal screw inserted in a normal bone was simulated, and the result is compared with the results of the expandable screw in osteoporotic bone. Lastly, strength of the designed pedicle screw in a foam block is also verified with experiment. The reported finite element simulations and experiments are the proof for the concept of nitinol expandable-retractable elements on a pedicle screw which validate the functionality in a pullout test.

  19. Anodizing color coded anodized Ti6Al4V medical devices for increasing bone cell functions

    Directory of Open Access Journals (Sweden)

    Webster TJ

    2013-01-01

    Full Text Available Alexandra P Ross, Thomas J WebsterSchool of Engineering and Department of Orthopedics, Brown University, Providence, RI, USAAbstract: Current titanium-based implants are often anodized in sulfuric acid (H2SO4 for color coding purposes. However, a crucial parameter in selecting the material for an orthopedic implant is the degree to which it will integrate into the surrounding bone. Loosening at the bone–implant interface can cause catastrophic failure when motion occurs between the implant and the surrounding bone. Recently, a different anodization process using hydrofluoric acid has been shown to increase bone growth on commercially pure titanium and titanium alloys through the creation of nanotubes. The objective of this study was to compare, for the first time, the influence of anodizing a titanium alloy medical device in sulfuric acid for color coding purposes, as is done in the orthopedic implant industry, followed by anodizing the device in hydrofluoric acid to implement nanotubes. Specifically, Ti6Al4V model implant samples were anodized first with sulfuric acid to create color-coding features, and then with hydrofluoric acid to implement surface features to enhance osteoblast functions. The material surfaces were characterized by visual inspection, scanning electron microscopy, contact angle measurements, and energy dispersive spectroscopy. Human osteoblasts were seeded onto the samples for a series of time points and were measured for adhesion and proliferation. After 1 and 2 weeks, the levels of alkaline phosphatase activity and calcium deposition were measured to assess the long-term differentiation of osteoblasts into the calcium depositing cells. The results showed that anodizing in hydrofluoric acid after anodizing in sulfuric acid partially retains color coding and creates unique surface features to increase osteoblast adhesion, proliferation, alkaline phosphatase activity, and calcium deposition. In this manner, this study

  20. [Ultrasound bone densitometry in children and adolescents; Italian refence curves with multi-site device (Omnisense)].

    Science.gov (United States)

    Pedrotti, L; Mora, R; Bertani, B; Tuvo, G; Galli, G B; Pazzano, S; Quattrini, F; Crivellari, I

    2007-01-01

    The values of bone density represent one of the best parameters for the prediction of the risk of fracture in the adult. Since the peak of bone mass depends over that on genetic factors also on modifiable environmental factors, the evaluation of the state of bone health in paediatric populations has assumed great importance; the ultrasound techniques seem to represent a potential alternative to DXA and QTC. Using Omnisense device (Omnisense, Sunlight Ultrasound Technologies) we have evaluated the bone strength in a champion of 652 children and teen-agers aged 6-18 (328 females, 324 males). The measurements have been made at the distal third of the radius and midshaft tibia. The purpose has been to record the values of SOS in a healthy paediatric population, building a normal database and to find a correlation between the SOS values and anthropometric data, dietary factors and physical activity. The comparison with an analogous study conducted by other Authors prompted us to conclude that in the paediatric population the construction of proper curves of reference, with which to compare the data of the patients, is essential to avoid errors in the evaluation of bone density, in agreement with how much already underlined in literature. Besides a correct interpretation of the data obtained with ultrasounds systems asks for a change of the thresholds values established by the OMS for the diagnosis of osteopenia/osteoporosis with the DXA. As already happened for the adult population in children also it will be therefore necessary to compare a great number of pathological subjects with the normal database, establishing so the new values of Z-Score and giving a clinical meaning to the effected measurements.

  1. Flexible fixation and fracture healing

    DEFF Research Database (Denmark)

    Schmal, Hagen; Strohm, Peter C; Jaeger, Martin

    2011-01-01

    , noncomminuted fractures. External fixation uses external bars for stabilization, whereas internal fixation is realized by subcutaneous placement of locking plates. Both of these "biologic" osteosynthesis methods allow a minimally invasive approach and do not compromise fracture hematoma and periosteal blood...... of articular fractures. They allow for subchondral stabilization using small-diameter angular stable screws as well as buttressing of the joint and the metaphyseal component of a fracture. Biomechanically, they can be far stiffer than external fixators, because subcutaneous plates are located much closer...... to the bone surface than external fixator bars. External fixators have the advantage of being less expensive, highly flexible, and technically less demanding. They remain an integral part of orthopaedic surgery for emergent stabilization, for pediatric fractures, for definitive osteosynthesis in certain...

  2. Application of the active shape model in a commercial medical device for bone densitometry

    DEFF Research Database (Denmark)

    Thodberg, Hans Henrik; Rosholm, Anders

    2003-01-01

    Osteoporosis is a common disorder characterised mainly by low bone mineral density (BMD), and leading to an increased risk of fracture. We have developed a new device that estimates BMD from ordinary hand radiographs. A crucial element of this method is the reconstruction of the metacarpals. This......-posure system, version 2.0) has been approved by the FDA, and more than 100 units have been sold.The concept of the translation operator is generalised to the more active shape model (MASM), which also allows a natural integration with the active appearance model....

  3. The influence of sacral morphology on the existence of secure S1 and S2 transverse bone corridors for iliosacroiliac screw fixation.

    Science.gov (United States)

    Mendel, T; Noser, H; Kuervers, J; Goehre, F; Hofmann, G O; Radetzki, F

    2013-12-01

    Sacroiliac (SI) screw fixation for unstable pelvic fractures stands out as the only minimally invasive method among all other ORIF procedures. A strictly transverse screw trajectory is needed for central or bilateral fracture patterns up to a complete iliosacroiliac fixation. However, secure screw insertion is aggravated by a narrow sacroiliac bone stock. This study investigates the influence of a highly variable sacral morphology to the existence of S1 and S2 transverse corridors. The analysis contained in this study is based on 125 CT datasets of intact human pelvises. First, sacral dysplasia was identified using the "lateral sacral triangle" method in a lateral 3-D semi-transparent pelvic view. Second, 3-D corridors for a 7.3mm screw in the upper two sacral levels were visualised using a proprietary IT workflow of custom-made programme scripts based on the Amira(®)-software. Shape-describing measurement variables were calculated as output variables. The results show a significant linear correlation between ratioT and the screw-limiting S1 isthmus height (Pearson coefficient of 0.84). A boundary ratio of 1.5 represented a positive predictive value of 96% for the existence of a transverse S1-corridor for at least one 7.3mm screw. In 100 out of 125 pelvises (80%), a sufficient S1 corridor existed, whereas in 124 specimens (99%), an S2 corridor was found. Statistics revealed significantly larger S1 and S2 corridors in males compared to females (pS1 and 1 screw in S2. The expanse of the S1 corridor is highly influenced by the dimensions of the dysplastic elevated upper sacrum, whereas the S2 corridor is not affected. Hence, in dysplastic pelvises, sacroiliac screw insertion should be recommended into the 2nd sacral segment. Our IT workflow for the automatic computation of 3-D corridors may assist in surgical pre-operative planning. Furthermore, the workflow could be implemented in computer-assisted surgery applications involving pelvic trauma.

  4. 石膏固定和空心螺钉内固定修复腕部舟状骨新鲜骨折:功能恢复比较%Plaster fixationversus cannulated screw internal fixation for the wrist scaphoid bone fresh fracture:comparison of functional recovery

    Institute of Scientific and Technical Information of China (English)

    卡依沙尔•买买提明; 赵岩

    2015-01-01

      结果与结论:随访3-6个月对比分析石膏组和空心螺钉组患者腕关节功能Cooney评分,空心螺钉组优9例,良1例,可1例,差0例;石膏组优1例,良5例,可3例,差2例,空心螺钉组患者治疗后优良率为91%,石膏组患者治疗后优良率为55%,空心螺钉组显著高于石膏组(t=4.817,P OBJECTIVE:To compare and analyze functional recovery of the wrist scaphoid bone fresh fracture after plaster fixation and internal fixation. METHODS: Twenty-two patients with wrist scaphoid bone fresh fracture were recruited from the First Affiliated Hospital of Xinjiang Medical University from March 2012 to March 2014, and the injury time was 2 hours to 12 days. Preoperative X-ray films revealed that, the involved patients had no wrist scaphoid bone colapses, lunate bone dislocation, ischemic necrosis of bone and osseous changes. Al the cases showed shift, unstable fractures. According to the patient’s wiling and the surgical method, the involved patients were divided into two groups, receiving plaster fixation and cannulated screw internal fixation respectively. Each group contained 11 cases. Wrist joint function was evaluated using Cooney score system. There was no significant difference in the age distribution and gender between the two groups (P > 0.05). RESULTS AND CONCLUSION: At 3-6 months of folow-up, wrist joint function of patients in the two groups was compared and analyzed with Cooney scores. According to the Cooney scores, nine cases in internal fixation group were excelent, 1 good, 1 fair and none poor; one case in plaster fixation group was excelent, 5 good, 3 fair, and 2 poor. The excelent and good rate in the internal fixation group was significantly higher than that in the plaster fixation group (91%, 55%,t=4.817,P < 0.05). Although plaster fixation has certain effects on wrist scaphoid bone fresh fracture, open reduction and canulated screw fixation has obvious effect and promotes the

  5. Studies on Poly(propylene fumarate-co-caprolactone diol Thermoset Composites towards the Development of Biodegradable Bone Fixation Devices

    Directory of Open Access Journals (Sweden)

    M. Jayabalan

    2009-01-01

    Full Text Available The effect of reinforcement in the cross-linked poly(propylene fumarate-co-caprolactone diol thermoset composites based on Kevlar fibres and hydroxyapatite was studied. Cross-linked poly(propylene fumarate-co-caprolactone diol was also studied without any reinforcement for comparison. The reinforcing fibre acts as a barrier for the curing reaction leading to longer setting time and lesser cross-link density. The fibre and HA reinforced composites have almost the same compressive strength. Nonreinforced material undergoes greater degree of swelling. Among the reinforced materials, the hydroxyapatite reinforced composite has a much higher swelling percentage than the fibre reinforced one. The studies on in vitro degradation of the cured materials reveal hydrolytic degradation in Ringer's solution and PBS medium during aging. All the three materials are found to swell initially in Ringer's solution and PBS medium during aging and then undergo gradual degradation. Compression properties of these cross-linked composites increase with aging; HA reinforced composite has the highest compressive strength and compressive modulus, whereas the aged fibre-reinforced composite has the least compressive strength and modulus.

  6. Finite Element Simulation and Additive Manufacturing of Stiffness-Matched NiTi Fixation Hardware for Mandibular Reconstruction Surgery

    Directory of Open Access Journals (Sweden)

    Ahmadreza Jahadakbar

    2016-12-01

    Full Text Available Process parameters and post-processing heat treatment techniques have been developed to produce both shape memory and superelastic NiTi using Additive Manufacturing. By introducing engineered porosity, the stiffness of NiTi can be tuned to the level closely matching cortical bone. Using additively manufactured porous superelastic NiTi, we have proposed the use of patient-specific, stiffness-matched fixation hardware, for mandible skeletal reconstructive surgery. Currently, Ti-6Al-4V is the most commonly used material for skeletal fixation devices. Although this material offers more than sufficient strength for immobilization during the bone healing process, the high stiffness of Ti-6Al-4V implants can cause stress shielding. In this paper, we present a study of mandibular reconstruction that uses a dry cadaver mandible to validate our geometric and biomechanical design and fabrication (i.e., 3D printing of NiTi skeletal fixation hardware. Based on the reference-dried mandible, we have developed a Finite Element model to evaluate the performance of the proposed fixation. Our results show a closer-to-normal stress distribution and an enhanced contact pressure at the bone graft interface than would be in the case with Ti-6Al-4V off-the-shelf fixation hardware. The porous fixation plates used in this study were fabricated by selective laser melting.

  7. Absorbable fixation in forefoot surgery: a viable alternative to metallic hardware.

    Science.gov (United States)

    Nielson, David L; Young, Nathan J; Zelen, Charles M

    2013-07-01

    After 4 to 8 weeks of normal primary bone healing, rigid internal fixation is no longer required. Newer generation absorbable implants have become reliable and cost-effective alternatives to metallic hardware. Modern implants are formulated to have increased strength and smoother resorption over the course of 18 to 24 months, which decreases the possibility of local inflammation. Historically, bioresorbable screws can be time consuming to insert, but newer devices are being developed that help ease their insertion. A case of a bunionectomy is presented with double osteotomy on a 40-year-old nurse fixated with polyglycolic acid and poly-l-lactic acid copolymer screws.

  8. 不同固定方式对腱-骨愈合界面影响的形态学研究%Effect of different fixations on tendon-bone healing interface:a morphological study

    Institute of Scientific and Technical Information of China (English)

    刘建锋; 李艳菊

    2013-01-01

    背景:关节镜下重建交叉韧带已得到广泛应用,关于腱骨愈合状态的研究多集中在患肢功能恢复以及愈合程度及稳定性观察方面。  目的:了解韧带重建过程中各种固定方式对肌腱-骨界面愈合的影响。  方法:2009年7月至2009年9月以长白二号体重100千克左右的八头成年猪的双膝关节作为实验对象进行动物实验,采用四种固定方式对腱-骨进行固定,包括纽扣接骨板悬吊固定、肌腱包裹自体松质骨方式、界面挤压螺钉固定、横穿可吸收钉固定,对手术后6周、12周时界面愈合的情况进行病理切片观察。  结果:纽扣接骨板固定模式腱骨界面愈合均匀,理论抗拉力大,相反固定物对腱骨界面干扰明显的界面愈合不理想,骨纤维细胞排列不整齐,理论拉力降低,尤其表现在界面挤压螺钉方面;对于有自体松质骨植入的在腱骨愈合过程中活性骨质坏死,无促进腱骨愈合的作用。  结论:在腱骨愈合过程中界面固定方式对早期愈合有不同程度的影响,悬吊固定方式腱-骨愈合界面形态学表现理想。%Background:The reconstruction of cruciate ligament under arthroscope has been widely applied. Nowadays, the study on tendon-bone healing is mostly focused on function recovery of patients and stability of healing. Objective:The purpose of the study is to explore the influence of different fixed styles to tendon-bone healing in the process of ligament reconstruction. Methods:From July 2009 to September 2009, eight adult Landrace II pigs weighing 100 kg was used as experiment animal and divided into four groups (n=2). Four tendon-bone fixed methods were applied in both knee in each group respectively, including button-plate suspension fixation, autologous bone tendon wrapped mode, interface extrusion screw, and adsorb-able screw. The healing of interface was observed at 6 and 12 weeks

  9. 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.

  10. 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.

  11. Clinical and Analytical Evaluation of a Single-Vial Stool Collection Device with Formalin-Free Fixative for Improved Processing and Comprehensive Detection of Gastrointestinal Parasites.

    Science.gov (United States)

    Couturier, Brianne A; Jensen, Ryan; Arias, Nora; Heffron, Michael; Gubler, Elyse; Case, Kristin; Gowans, Jason; Couturier, Marc Roger

    2015-08-01

    Microscopic examination of feces is a standard laboratory method for diagnosing gastrointestinal parasite infections. In North America, the ovum and parasite (O&P) examination is typically performed using stool that is chemically fixed in polyvinyl alcohol (PVA) and formalin, after which the stool is concentrated by filtration to enhance sensitivity. Mini Parasep solvent-free (SF) tubes allow collection and concentration within a single collection vial. The goal of the study was to determine whether consolidated processing and concentration with the Parasep tubes using an alcohol-based fixative (Alcorfix) provide O&P examinations equivalent to or better than those done by processing of PVA-formalin-fixed stool using a SpinCon concentration device. Parasep tubes revealed filtration performance equivalent to that of the SpinCon concentration device using PVA-formalin-fixed stool containing protozoa. Specimens cocollected in Parasep tubes containing PVA-formalin and Alcorfix revealed comparable morphology and staining for various protozoa. Alcorfix effectively fixed live Cryptosporidium and microsporidia such that morphology and staining were conserved for modified acid-fast and modified trichrome stains. A work flow analysis revealed significant time savings for batches of 10 or 30 O&P specimens in tubes with Alcorfix compared to the amount of time that it took to analyze the same number of specimens in tubes with PVA-formalin. The direct hands-on time savings with Mini Parasep tubes were 17 min and 41 s and 32 min and 1 s for batches of 10 and 30 specimens, respectively. Parasep tubes containing Alcorfix provide significant work flow advantages to laboratories that process medium to high volumes of O&P specimens by streamlining processing and converting to a single tube. These improvements in work flow, reduction of the amount of formalin used in the laboratory, and equivalent microscopy results are attractive advancements in O&P testing for North American

  12. 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

    years and weighted between 1.8 and 16.0kg. Two dogs had bilaterally fractures stabilized, totalizing 18 ilium osteosynthesis performed. The ilium was achieved via lateral approach. The fractures were reduced and on each bone segment was inserted two to three screws connected by a band tension. Over them a mixture of bone cement added with cefalozin was applied as a definitive fixation device. Suture of soft tissues was made as usual. Postoperative evaluations were periodically performed. After 3 months, 15 dogs showed proper use of the operated limb. Radiographic signs of complete bone healing were observed between 60 and 90 days. Stabilization failure occurred in two cases and one of them required another surgery. Both cases showed a good outcome. Based on these results it was possible to conclude that in dogs weighting up to 16.0kg, iliac fracture fixation with screws, orthopedic wires and bone cement is an efficient technique promoting early limb use and complete bone healing as a result of adequate bone stabilization.

  13. Audiometric Comparison Between the First Patients With the Transcutaneous Bone Conduction Implant and Matched Percutaneous Bone Anchored Hearing Device Users

    NARCIS (Netherlands)

    Rigato, C.; Reinfeldt, S.; Hakansson, B.; Jansson, K.J.; Hol, M.K.S.; Eeg-Olofsson, M.

    2016-01-01

    HYPOTHESIS: The transcutaneous bone conduction implant (BCI) is compared with bone-anchored hearing aids (BAHAs) under the hypothesis that the BCI can give similar rehabilitation from an audiological as well as patient-related point of view. BACKGROUND: Patients suffering from conductive and mixed h

  14. 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.

  15. Prosthesis, bone graft and internal fixation and bone cement filling for treatment of giant cell tumor of bone%假体置换、植骨内固定及骨水泥填充治疗骨巨细胞瘤

    Institute of Scientific and Technical Information of China (English)

    广东; 王亚军; 赵凡

    2011-01-01

    BACKGROUND: Artificial joint replacement or allogeneic bone fixation and bone substitute materials filling are common ways torepair bone defects in giant cell tumor of bone after curettage, so which one is more ideal?OBJECTIVE: To understand the staging standard of giant cell tumors through access to Chinese and English literature abouttreatment for giant cell tumor of bone, and to compare different therapies, bone graft, bone cement filling and prosthesis.METHODS: A computer based search of CNKI using keywords of “tumor-type prosthesis, giant cell tumor of bone, bone graft,bone cement” and Elsevier Science and Pringer-Link using keywords of “giant cell tumor of bone, therapy, tumor-type prosthesis”were performed to retrieve relevant articles. Totally 346 articles were retrieved, and finally 26 were included in result analysis.RESULTS AND CONCLUSION: The traditional treatments for giant cell tumor have a higher recurrence rate. The bone graft maynot be able to fill the entire bone cavity, bone cement materials cannot be easy to be fused with the host. Tumor-type prosthesisshows a good effect on giant cell tumor of bone, but it is still inadequate. However, special prosthesis joints can repair bone defectsfollowing giant cell tumor of bone according to individualized treatment needs, which is an effective and reliable surgical method aswell as the main research direction for the future treatment of giant cell tumor of bone.%背景:人工关节置换或同种异体骨内固定及骨组织替代材料填充是修复骨巨细胞瘤刮除后骨缺损的常见方式,那么哪一种更理想呢?目的:通过查阅关于骨巨细胞瘤治疗方面的中英文文献,了解骨巨细胞瘤的分期标准并比较以植骨内固定、骨水泥填充及假体置换为主的治疗方法.方法:中国知网数据库输入中文检索词"肿瘤型假体,骨巨细胞瘤,植骨内固定,骨水泥",Elesvier Science和Springer-Link 数据库输入英文检索词"giant cell

  16. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  17. Development of a guided bone regeneration device using salicylic acid-poly(anhydride-ester) polymers and osteoconductive scaffolds.

    Science.gov (United States)

    Mitchell, Ashley; Kim, Brian; Cottrell, Jessica; Snyder, Sabrina; Witek, Lukasz; Ricci, John; Uhrich, Kathryn E; O'Connor, J Patrick

    2014-03-01

    Successful repair of craniofacial and periodontal tissue defects ideally involves a combined therapy that includes inflammation modulation, control of soft tissue infiltration, and bone regeneration. In this study, an anti-inflammatory polymer, salicylic acid-based poly(anhydride-ester) (SAPAE) and a three-dimensional osteoconductive ceramic scaffold were evaluated as a combined guided bone regeneration (GBR) system for concurrent control of inflammation, soft tissue ingrowth, and bone repair in a rabbit cranial defect model. At time periods of 1, 3, and 8 weeks, five groups were compared: (1) scaffolds with a solid ceramic cap (as a GBR structure); (2) scaffolds with no cap; (3) scaffolds with a poly(lactide-glycolide) cap; (4) scaffolds with a slow release SAPAE polymer cap; and (5) scaffolds with a fast release SAPAE polymer cap. Cellular infiltration and bone formation in these scaffolds were evaluated to assess inflammation and bone repair capacity of the test groups. The SAPAE polymers suppressed inflammation and displayed no deleterious effect on bone formation. Additional work is warranted to optimize the anti-inflammatory action of the SAPAE, GBR suppression of soft tissue infiltration, and stimulation of bone formation in the scaffolds and create a composite device for successful repair of craniofacial and periodontal tissue defects.

  18. Biomechanical comparison of interspinous distraction device and facet screw fixation system on the motion of lumbar spine: a finite element analysis

    Institute of Scientific and Technical Information of China (English)

    Wang Hongwei; Wang Xiaohong; Chen Wenchuan; Zhao Fuqiang; Xiang Liangbi; Zhou Yue; Cheng Chengkung

    2014-01-01

    Background A large amount of biomechanical and clinical evidence from previous studies suggest the efficiency of the two different posterior lumber non-fusion methods,interspinous distraction device (ISDD) and facet screw fixation system (FSS),but the biomechanical comparison of ISDD and FSS has not been thoroughly clarified.Methods In the current study,finite element methods were used to investigate the biomechanical comparison of ISDD and FSS.The range of motion (ROM),intradiscal pressure (IDP) and the protective effects gained by maintaining disc heights were evaluated.Results The ROM was similar between the two non-fusion methods under static standing,flexion and lateral bending.The FSS appeared to be more effective in resisting extension.At the implanted level L3/4,FSS displayed better results for maintaining and increasing posterior disc heights.At the L4/5 level in extension and lateral bending,FSS was better than ISDD,with comparable results observed in other motions.Comparing the posterior and lateral disc heights,FSS appeared to be more effective than ISDD.FSS also had a minor effect on the inferior adjacent segment than ISDD.FSS was more effective in reducing IDP than ISDD in extension.Conclusion Through the finite element analysis study,it can be seen that FSS demonstrates more beneficial biomechanical outcomes than does ISDD,such as being more effective in resisting extension,maintaining and increasing lumbar disc heights and reducing the inferior adjacent IDP in extension.

  19. Fluid Flow Shear Stress Stimulation on a Multiplex Microfluidic Device for Rat Bone Marrow Stromal Cell Differentiation Enhancement

    Directory of Open Access Journals (Sweden)

    Chia-Wen Tsao

    2015-12-01

    Full Text Available Microfluidic devices provide low sample consumption, high throughput, high integration, and good environment controllability advantages. An alternative to conventional bioreactors, microfluidic devices are a simple and effective platform for stem cell investigations. In this study, we describe the design of a microfluidic device as a chemical and mechanical shear stress bioreactor to stimulate rat bone marrow stromal cells (rBMSCs into neuronal cells. 1-methyl-3-isobutylxanthine (IBMX was used as a chemical reagent to induce rBMSCs differentiation into neurons. Furthermore, the shear stress applied to rBMSCs was generated by laminar microflow in the microchannel. Four parallel microfluidic chambers were designed to provide a multiplex culture platform, and both the microfluidic chamber-to-chamber, as well as microfluidic device-to-device, culture stability were evaluated. Our research shows that rBMSCs were uniformly cultured in the microfluidic device and differentiated into neuronal cells with IBMX induction. A three-fold increase in the neuronal cell differentiation ratio was noted when rBMSCs were subjected to both IBMX and fluid flow shear stress stimulation. Here, we propose a microfluidic device which is capable of providing chemical and physical stimulation, and could accelerate neuronal cell differentiation from bone marrow stromal cells.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. Is There a Role for an Ultrasonic Bone-Cutting Device in Adult Spinal Deformity: A Safety and Reproducibility Study

    Directory of Open Access Journals (Sweden)

    Pooria Hosseini

    2016-07-01

    Full Text Available Background Ultrasonic bone-cutting devices (UBC are new cutting tools and have low frequency ultrasonic blade. There is limited data on the safety and effectiveness of using ultrasonic bone-cutting devices in the treatment of adult spinal deformities (ASD. Objectives This Retrospective review of prospectively collected data was designed to determine if the use of an ultrasonic bone-cutting device is safe in the adult spinal deformity population and to compare its effectiveness in blood loss reduction by using a comparison group from a prospective multicenter database of adult spinal deformity patients. Methods Nineteen consecutive surgical ASD cases in which the UBC was used were compared with 19 propensity-matched cases from a prospective ASD database in which conventional bone cutting instruments were used. The two groups were matched based on age, ASA, and number of levels fused posteriorly. The need for blood transfusion, volume of blood transfusion if required, estimated blood loss (EBL, and total operating time were compared between the two groups. Data were analyzed using non-parametric Mann-Whitney U test and Spearman’s Correlation test (P < 0.05. Results There was no statistically significant difference in any measured parameter between the two groups. While the EBL difference between the two groups (925 mL in the study group vs. 1628 mL in the control group was not statistically significant (P = 0.142, the 703 mL difference is clinically relevant. In addition, no complications directly related to the use of the UBC were reported. Conclusions The use of an ultrasonic bone-cutting device was shown to be safe and effective in the surgical treatment of ASD. It resulted in a 43% reduction in EBL, which was clinically relevant and statistically non-significant, without the addition of any complications. We did not identify statistical differences in transfusion rates, EBL, or operative time, which may be due to our small sample size.

  5. 颈椎前路减压植骨钛板内固定治疗颈脊髓损伤%Treatment of Cervical Spinal Cord Injury by Anterior Decompression, Bone Graft and Titanium Plate Internal Fixation

    Institute of Scientific and Technical Information of China (English)

    沈宁江; 王先安; 林庆彪; 林明侠; 陈建

    2013-01-01

    Objective To evaluate the clinical efficacy of anterior decompression, bone graft and internal fixation for cervical spine fracture with cervical spinal cord injury. Methods 215 cases of cervical spine fracture with cervical spinal cord injury had been treated by the method of anterior decompression,iliac bone graft and cervical locking titanium plate fixation. X-rays were taken regularly after surgery and recovery of spinal cord function were recorded. Results 184 cases were followed for an average time of 3. 5 years. Bone graft union was achieved 3 months after surgery. The cervical intervertebral height and the physiological curvature maintained satisfactory without implant complications. Nerve function of 172 patients improved 1 to 2 degree. Only 12 cases with stage A nerve function obtained no recovery. Conclusion Patients of cervical fracture with cervical spinal cord injury should undergo surgery of anterior decompression,bone graft and plate fixation as soon as possible. It is good to spinal cord function recovery. The injured segments can obtain instant and firm stability, which makes care and functional exercises easier.%目的 评价颈椎前路减压植骨内固定治疗颈椎骨折合并颈脊髓损伤的临床疗效.方法 对215例颈椎骨折合并颈脊髓损伤的患者施行颈椎前路减压、自体髂骨植骨和颈椎带锁钛板内固定术.术后定期复查X线片,判定脊髓功能恢复情况.结果 随访184例患者,平均随访时间3.5年.术后3个月植骨块获得骨性愈合,颈椎椎间高度和生理曲度维持满意,无内置物并发症,172例患者神经功能提高1~2级,仅12例A级患者神经功能无恢复.结论 颈椎骨折合并颈脊髓损伤应尽早行前路减压、植骨、钛板内固定术,有利于脊髓功能恢复,能使损伤节段获得即刻、坚强的稳定,方便护理和功能锻炼.

  6. 经前路减压植骨融合内固定术治疗胸腰椎爆裂骨折%The treatment of the thoracolumbar spina burst fracture: planted bones fusion and internal fixation by anterior decompression

    Institute of Scientific and Technical Information of China (English)

    汪红; 刘跃洪; 刘树平; 周宇; 徐巍

    2012-01-01

    目的 探讨经前路减压、椎间植骨融合内固定术治疗胸腰椎爆裂骨折的疗效.方法 对22例胸腰椎爆裂骨折患者行前路减压、推间植骨融合内固定术,并对患者神经功能、骨折愈合情况进行术前术后对比分析.结果 平均手术时间3.5h,平均失血量800ml,平均住院时间10d.平均随访18个月,脊柱稳定性好,序列好,未出现螺钉松动、钛网下沉等并发症,植骨均愈合.末次随访时神经功能均较术前恢复1~3级.结论 经前路减压植骨融合内固定术治疗胸腰椎爆裂骨折能彻底减压,植骨融合率高,固定效果好,神经功能改善明显,具有推广应用价值.%Objective To explore the clinical efficiency of the treatment of the thoracolumbar spina burst fracture through planted bones fusion and internal fixation by anterior decompression. Methods Between January 2008 and December 2010. 22 cases of thoracolumbar spina burst fracture were treated by planted bones fusion and internal fixation by anterior decompression, including 16 males and 6 females with an age range of 22-65 years (44. 5 years on average). The injury was caused by fall from height in 12cases, by traffic accident in 8 cases and by weight crushing in 2 cases. The injury segments were 2 cases of thoracic 11, 8 cases of thoracic 12, 10 cases of lumbar 1 and 2 cases of lumbar 2. Preopera-tive CT showed that all 22 cases suffered from spinal canal occupancy, fracture fragments migrated into spinal canal and spinal dura mater compression. There are 4 cases of Grade A, 6 cases of Grade B. 8 cases of Grade C. 2 cases of Grade D and 2 cases of Grade E according to Frankel grading of neurologic status before surgery. It was an average of 6. 5 days from injury to operation. The mean operative time was 3. 5 hours and the mean blood loss was 800 ml. The mean time in hospital was 10 days and the mean follow-up time was 18 months. The comparative analysis before and after surgery of all patients in

  7. 双维控制牙槽骨牵张器的成骨效应%A bidirectional alveolar bone distraction device for osteogenesis of alveolar bone

    Institute of Scientific and Technical Information of China (English)

    黄代营; 聂二民; 孙明; 黎炽彬

    2011-01-01

    背景:牵张成骨增高牙槽嵴在基础研究及临床已有很多成功报道,双维控制垂直牙槽骨牵张器可有效防止单向直线牵张器行牙槽骨牵张发生轴向移位.目的:研制双维控制的牙槽骨牵张器,并通过动物实验观察其成骨效应.方法:选择杂种犬4只,拔除一侧下颌前磨牙形成萎缩牙槽骨模型.1个月后行骨切开放置双维牵张器,7 d后垂直牵张 (1 mm/d,共5 d).完成垂直牵张后,利用双维牵张器颊向控制功能将移动骨块颊向牵出(大约2.4 mm),固定2个月后行大体观察及组织学检查.结果与结论:4只犬中2只黏膜伤口愈合良好,2只黏膜出现裂开,行二次缝合后愈合,牵张器固位良好,未出现松动、脱落.牵张骨块向垂直向及颊向的位移量满足实验目的要求,牙槽骨垂直向高度平均增加(5.0±0.2) mm,颊向宽度平均增加(2.4±0.3) mm.大体观察及组织学检查均证实牵张成骨的骨块新骨形成良好.说明双维控制垂直牙槽骨牵张器能较好的控制移动骨块垂直或颊向的移动方向,并且新骨形成良好.%BACKGROUND: Alveolar bone augmentation using a unidirectional dist raction device may lead to axial displacement. Abidirectional distraction device can control the vertical and buccal-lingual directions. But studies regarding this have been rarelyreported.OBJECTIVE: To develop a bidirectional alveolar bone distraction device and to investigate its effects on osteogenic effectsthrough an animal experiment.METHODS: Four adult mongrel dogs were established into models of alveolar bone atrophy by extraction of unilateral mandiblepremolars. After 1 month, alveolar bone was cut open and a bilateral distraction device was placed. Seven days later, thedistraction was started at a rate of 1 mm/day for 5 days. At last, buccal-lingual direction distraction (approximately 2.4 mm) wastaken for once, followed by a consolidation period of 2 months. Subsequently, gross observation and

  8. Experience of Clinical the Load of Streptomycin Powder Bone Morselized Bone Fusion and Internal Fixation for the Treatment of Spinal Tuberculosis%负载链霉素粉骨颗粒植骨融合内固定术治疗脊柱结核的治疗体会

    Institute of Scientific and Technical Information of China (English)

    王永松; 王冶; 陈志龙; 王群芳

    2015-01-01

    目的:探讨负载链霉素粉骨颗粒植入融合及内固定术治疗脊柱结核的临床疗效和应用价值。方法对16例脊柱结核使用一期病灶清除,带链霉素粉骨颗粒植入融合和钉棒系统内固定治疗。结果术后腰痛缓解93.2%。术后1年X线片植骨融合率达96.2%。结论治疗腰椎结核采用一期病灶清除,负载链霉素粉骨颗粒植入融合,钉棒系统内固定具有良好的效果。%Objective To evaluate the load streptomycin powder particles are bone fusion and internal fixation in the treatment of spinal tuberculosis curative ef ect and application value. Methods 16 cases of spinal tuberculosis using a phase lesions cleared, with streptomycin powder particles are bone fusion and good nail internal fixation treatment system. Results 93.2% postoperative back pain relief. A year after X line piece of bone graft fusion rate was 96.2%. Conclusion Treatment of lumbar spinal tuberculosis using a phase lesions cleared, load streptomycin powder particles are bone fusion and internal fixation of screw rod system has a good ef ect.

  9. 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

  10. Complications of rigid internal fixation.

    Science.gov (United States)

    Campbell, Chris A; Lin, Kant Y

    2009-03-01

    Over the past 20 years, there have been many advances in the development of bone fixation systems used in the practice of craniomaxillofacial surgery. As surgical practices have evolved, the complications of each technologic advance have changed accordingly. Interfragmentary instability of interosseous wiring has been replaced by the risk of exposure, infection, and palpability of plate and screw fixation systems. The improved rigidity of plate fixation requires anatomic alignment of fracture fragments. Failure to obtain proper alignment has led to the phenomenon known as "open internal fixation" of fracture fragments without proper reduction. The size of the plates has decreased to minimize palpability and exposure. However limitations in their application have been encountered due to the physiologic forces of the muscles of mastication and bone healing. In the pediatric population, the long-standing presence of plates in the cranial vault resulted in reports of transcranial migration and growth restriction. These findings led to the development of resorbable plating systems, which are associated with self-limited plate palpability and soft tissue inflammatory reactions. Any rigid system including these produces growth restriction in varying amounts. In this discussion, we review the reported complication rates of miniplating and microplating systems as well as absorptive plating systems in elective and traumatic craniofacial surgery.

  11. 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.

  12. Metallic Fixation of Mandibular Segmental Defects: Graft Immobilization and Orofacial Functional Maintenance

    Science.gov (United States)

    Shayesteh Moghaddam, Narges; Jahadakbar, Ahmadreza; Amerinatanzi, Amirhesam; Elahinia, Mohammad; Miller, Michael

    2016-01-01

    Background: The aim of this study is to investigate the behavior of the healthy mandible under maximum molar bite force to demonstrate the problems associated with the current standard of care procedures for mandibular segmental defect reconstruction (ie, use of Ti–6Al–4V hardware and either a single- or double-barrel fibular graft). With current Ti–6Al–4V mandibular reconstruction hardware, there is a significant stiffness mismatch among the hardware, graft, and the remaining host anatomy. How the distribution of mechanical forces through the mandible is altered after a segmental bone loss and reconstruction is incompletely understood. Methods: We studied a healthy adult mandible for stress, strain, and reaction force distribution during normal mastication. Stress distribution of this model was then used to study problems encountered after mandibular segmental defect reconstructive surgery. We model the use of both single- and double-barrel fibular grafts to repair the loss of the left M1–3 containing segment of the mandible. These simulations were done using 2 sets of plates with different thicknesses. Results: We found that the stiffness mismatching between the fixation hardware and the graft and host bone causes stress shielding of that bone and stress concentrations in the fixation hardware and screws. These effects are expected, especially during the bone healing period. However, long term, this abnormal stress–strain distribution may lead to either the hardware’s failure due to stress concentration or graft failure due to bone resorption as a result of stress shielding. We found that the stress–strain distribution is more normal with a double-barrel fibular graft. Additionally, we found that thinner fixation plates can reduce stress shielding. Conclusion: The proposed model can be used to evaluate the performance and optimization of the fixation device.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. A 10-year follow-up of transpedicular screw fixation and intervertebral autogenous posterior iliac crest bone graft or intervertebral B-Twin system in failed back surgery syndrome

    Science.gov (United States)

    Cincu, Rafael; Lorente, Francisco de Asis; Gomez, Joaquin; Eiras, Jose; Agrawal, Amit

    2015-01-01

    Background: The spine surgeons have been combining anterior and posterolateral fusion (circumferential fusion) as the final solution to treat spinal disorders and many have been using it to treat failed back surgery syndrome (FBSS). In present study, we analyzed and compared the clinical and radiological outcomes in patients with transpedicular screw fixation and intervertebral autogenous posterior iliac crest bone graft or in patients with transpedicular screw fixation and intervertebral B-Twin system for FBSS with a follow-up period of 10 years after the surgery. Materials and Methods: This study was a retrospective case study performed on 55 patients with FBSS. Clinical and radiological changes were compared between the two groups of patients on the basis of improvement of back pain, radicular pain, and work capacity. Outcome was measured in terms of Oswestry Low Back Pain Disability Index, and the changes in pain and function were documented every year from before surgery until 2012. We analyzed the evolution of 55 cases of FBSS those underwent segmental circumferential posterior fusions from June 2001 to February 2003, operated by a single surgeon and followed up during 10 years until February 2012. The patients were divided into 2 groups: In 25 patients, posterolateral fusions with Legacy™ (Medtronic, Inc. NYSE: MDT) screws and intersomatic autogenous posterior iliac crest bone graft was performed, and, in 30 patients, posterolateral fusions with the same screws and intersomatic fusion B-Twin (Biomet Spain Orthopaedics, S.L.) system was performed. In all cases, we used posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) approach for intervertebral graft, and the artrodesis was supplemented at intertransverse level with Autologus Growth Factor (AGF-MBA INCORPORADO, S.A.). The outcome was measured in terms of Oswestry Low Back Pain Disability Index, and the changes in pain and function were documented every year and compared

  19. Titanium-Based Biomaterials for Preventing Stress Shielding between Implant Devices and Bone

    Directory of Open Access Journals (Sweden)

    M. Niinomi

    2011-01-01

    Full Text Available β-type titanium alloys with low Young's modulus are required to inhibit bone atrophy and enhance bone remodeling for implants used to substitute failed hard tissue. At the same time, these titanium alloys are required to have high static and dynamic strength. On the other hand, metallic biomaterials with variable Young's modulus are required to satisfy the needs of both patients and surgeons, namely, low and high Young's moduli, respectively. In this paper, we have discussed effective methods to improve the static and dynamic strength while maintaining low Young's modulus for β-type titanium alloys used in biomedical applications. Then, the advantage of low Young's modulus of β-type titanium alloys in biomedical applications has been discussed from the perspective of inhibiting bone atrophy and enhancing bone remodeling. Further, we have discussed the development of β-type titanium alloys with a self-adjusting Young's modulus for use in removable implants.

  20. 前路减压植骨可吸收螺钉内固定治疗颈椎病%The anterior decompression and bone grafting with bio-absorbable screw fixation for cervical spondylosis

    Institute of Scientific and Technical Information of China (English)

    王栋; 贺西京; 李浩鹏; 张健; 徐思越; 杨平林; 王国毓

    2009-01-01

    Objective:To observe the early clinical effect of the cervical spendylosis treated by the fixation with bio-absorbable screw after cervical anterior decompression and bone grafting.Method:26 cases suffered from cervical spondylosis who were treated by anterior compression,bone grafting and fixating with 2 bio-ab-serbable screws from Mar. 2007 to Sep. 2008,including 16 males and 10 females with an average age of 49.4 years (38-70 years ).There were 11 cases with cervical spondylotic myelopathy,5 with cervical spendylofic radieulopathy and 10 with mixed type of cervical spondylosis.Clinical data of these patients was analyzed ret-rospectively.One intervertebral space involvement was in 8 cases,and two spaces involvement in 18 cases.All patients underwent anterior decompression and bone grafting,in which the grafted bone was fixated by 2 bio-absorptive screws (PLLA,diameter:2.7mm) from the midline of graft bone to the bone surface of upper and lower vertebrae in 45°.Cervical collar was commonly used for 4-6 weeks after operation.All cases were fol-lowed-up every month in outpatient department to observe the improvement of symptoms and evaluate the fu-sion of bone graft.Neurological function recovery was observed by JOA score.Result:Operations of all cases were finished and screws were placed successfully.The operative incisions healed well.The excellent and good rate of symptom improvement was 84.2%,the graft fusion time was 3.3±0.6 months (range,3.2-4.6 months).No obvious complications were found.Conclusion:The cervical spendylosis with one or two-level involvement can be effectively treated by anterior decompression and bone grafting with bio-absorbable screw fixation.This operative method is safe and can avoid the complications induced by metal implants.%目的:观察颈椎前路减压植骨可吸收螺钉内同定治疗颈椎病的初步临床疗效.方法:2007年3月~2008年9月我院应用颈椎前路减压植骨可吸收螺钉

  1. Pitfalls during biomechanical testing - Evaluation of different fixation methods for measuring tendons endurance properties.

    Science.gov (United States)

    Hangody, Gy; Pánics, G; Szebényi, G; Kiss, R; Hangody, L; Pap, K

    2016-03-01

    The goal of the study was to find a proper technique to fix tendon grafts into an INSTRON loading machine. From 8 human cadavers, 40 grafts were collected. We removed the bone-patella tendon-bone grafts, the semitendinosus and gracilis tendons, the quadriceps tendon-bone grafts, the Achilles tendons, and the peroneus longus tendons from each lower extremity. We tested the tendon grafts with five different types of fixation devices: surgical thread (Premicron 3), general mounting clamp, wire mesh, cement fixation, and a modified clamp for an INSTRON loading machine. The mean failure load in case of surgical thread fixation was (381N ± 26N). The results with the general clamp were (527N ± 45N). The wire meshes were more promising (750N ± 21N), but did not reach the outcomes we desired. Easy slippages of the ends of the tendons from the cement encasements were observed (253N ± 18N). We then began to use Shi's clamp that could produce 977N ± 416N peak force. We combined Shi's clamp with freezing of the graft and the rupture of the tendon itself demonstrated an average force of 2198 N ± 773N. We determined that our modified frozen clamp fixed the specimens against high tensile forces.

  2. Audiometric evaluation of an attempt to optimize the fixation of the transducer of a middle-ear implant to the ossicular chain with bone cement.

    NARCIS (Netherlands)

    Snik, A.F.M.; Cremers, C.W.R.J.

    2004-01-01

    Typically, an implantable hearing device consists of a transducer that is coupled to the ossicular chain and electronics. The coupling is of major importance. The Vibrant Soundbridge (VSB) is such an implantable device; normally, the VSB transducer is fixed to the ossicular chain by means of a speci

  3. A study on development of guideline on writing technical document for electrical medical devices: Bone absorptiometric X-ray system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Youl; Kim, Jae Ryang; Kim, Eun Rim; Lee, Jun Ho; Lee, Chang Hyung; Park, Chang Won [Medical Device Research Division, Ministry of Food and Drug Safety, Cheongju (Korea, Republic of)

    2016-06-15

    The market size of the bone absorptiometric X-ray system and the number of its approval by Ministry of Food and Drug Safety (MFDS) has annually increased, with a trend of increasing aging population and osteoporosis patients. For approval of manufactured or imported medical devices in Republic of Korea, it is required to submit its technical document. Therefore, it is need to develop the technical document guideline for the bone absorptiometric X-ray system for manufacturers, importers and reviewers. First of all, the technical documents which were already approved were examined and analyzed through MFDS approval administration system. Second, safety and performance test standards and methods that match international standards were drawn after conducting survey of the market status and the technology development trend for it, with examination and analysis of applicable domestic and overseas standards. Third, by operating industry-research-government cooperation, the guideline draft on writing technical document for the bone absorptiometric X-ray system was discussed, collecting their opinion. As a result, it is suitable to international and domestic condition, includes test evaluation methods and offer various information with appropriate examples to civil petitioner, when they write the technical documents.

  4. Bone mineral density assessment using the EOS low-dose X-ray device: a feasibility study.

    Science.gov (United States)

    Sapin, E; Briot, K; Kolta, S; Gravel, P; Skalli, W; Roux, C; Mitton, D

    2008-11-01

    To predict bone strength in the case of osteoporosis, it could be a real benefit to assess the three-dimensional (3D) geometry and the bone mineral density (BMD) with a single low-dose X-ray device, such as the EOS system (Biospace Med, Paris, France). EOS 3D reconstructions of the spine have already been validated. Thus, this study aims at evaluating the accuracy of this low-dose system as a densitometer first ex vivo. The European Spine Phantom (ESP) (number 129) was scanned ten times using both the EOS and a Hologic device (Hologic, Inc., Massachusetts, USA). Accuracy was given by the sum of the systematic error (difference between BMDs assessed and true values given by the phantom manufacturer) and the random error (coefficient of variation). EOS BMDs and Hologic BMDs of 41 ex-vivo vertebrae were calculated and compared. The reproducibility of the method evaluating the EOS BMD was assessed giving the coefficient of variation of three measurements of the 41 vertebrae. The accuracy of the EOS system is below 5.2 per cent, versus 7.2 per cent for the Hologic system in the same conditions. EOS BMDs are significantly higher than Hologic BMDs, but they are strongly correlated. The reproducibility of the method of assessment is equal to 0.95 per cent. The EOS system is accurate for ex-vivo BMD assessments, which is promising regarding the use of this new system to predict vertebral strength.

  5. Computational investigations of mechanical failures of internal plate fixation.

    Science.gov (United States)

    Chen, G; Schmutz, B; Wullschleger, M; Pearcy, M J; Schuetz, M A

    2010-01-01

    This paper investigated the biomechanics of two clinical cases of bone fracture treatments. Both fractures were treated with the same locking compression plate but with different numbers of screws as well as different plate materials. The fracture treated with 12 screws (rigid fixation) failed at 7 weeks with the plate breaking; the fracture with six screws (flexible fixation) endured the entire healing process. It was hypothesized that the plate failure in the unsuccessful case was due to the material fatigue induced by stress concentration in the plate. As the two clinical cases had different fracture locations and different plate materials, finite element simulations were undertaken for each fractured bone fixed by both a rigid and a flexible method. This enabled comparisons to be made between the rigid and flexible fixation methods. The fatigue life was assessed for each fixation method. The results showed that the stress in the rigid fixation methods could be significantly higher than that in flexible fixation methods. The fatigue analyses showed that, with the stress level in flexible fixation (i.e. with fewer screws), the plate was able to endure 2000 days, and that the plate in rigid fixation could fail by fatigue fracture in 20 days. The paper concludes that the rigid fixation method resulted in serious stress concentrations in the plate, which induced fatigue failure. The flexible fixation gave sufficient stability and was better for fracture healing.

  6. Study of Bone Grafting like Cone Pedicle for Thoracic and Lumbar Fracture in GSS Internal Fixation%胸腰段椎体骨折GSS内固定术经锥弓根等植骨的研究

    Institute of Scientific and Technical Information of China (English)

    唐凯

    2015-01-01

    Objective:To research on bone grafting like cone pedicle for thoracic and lumbar fracture in GSS internal fixation.Method:From February 2011 to February 2014,60 patients with thoracic and lumbar fracture in our hospital were given the fusion treatment of GSS internal fixation of pedicle screw-rod system, bone grafting in vertebral arch and posterolateral bone grafting.Result:After the operation, these patients were given postoperative follow-up.It was found that incision of 60 cases was primary healing.The X-ray showed that their spinal sequence and physiological curvature largely returned to normal.The height of vertebral body returned to 78%- 98% of the normal height.The reset rate was as high as 98%.Improvement in pain symptom and function was over 96%.No loose or fractured screw rods and no complications of spinal cord and nerve root injury were found.Conclusion:After the research, it is found that for the operation of thoracic and lumbar fracture, the application of vertebral arch bone grafting and vertebral plate posterior bone grafting, which stabilized the front, middle and posterior column of vertebral body, can avoid fractured screw as well as rod and loose pedicle screw.At the same time, it can avoid the vertebral body lose its height and also lighten the pain of the patients.Therefore, it will be the main trend of treatment of thoracic and lumbar fracture.%目的:对胸腰段椎体骨折GSS内固定术经锥弓根等植骨的研究。方法:回顾性分析本院2011年2月-2014年2月采用GSS椎弓根钉棒系统内固定加经椎弓椎椎体内植骨及后外侧植骨融合术治疗的60例胸腰椎骨折患者的临床资料。结果:术后随访,伤口均一期愈合,X线片显示脊柱序列和生理曲度基本恢复正常,椎体高度恢复到正常椎体高度的78%~98%,复位率达到98%,疼痛症状及功能改善96%以上,无脊髓及神经根损伤加重并发症,无螺钉棒松动、断裂,无矫形丢失无脊髓及

  7. 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.

  8. Effect of osteogenic periosteal distraction by a modified Hyrax device with and without platelet-rich fibrin on bone formation in a rabbit model: a pilot study.

    Science.gov (United States)

    Pripatnanont, P; Balabid, F; Pongpanich, S; Vongvatcharanon, S

    2015-05-01

    This study evaluated the effect of a modified Hyrax device and platelet-rich fibrin (PRF) on osteogenic periosteal distraction (OPD). Twelve adult male New Zealand white rabbits were separated into two main groups (six in each) according to the duration of the consolidation period (4 or 8 weeks). In each main group, the animals underwent OPD of the left and right sides of the mandible and were divided into four subgroups (three animals per group): device vs. device+PRF, and PRF vs. sham. Radiographic, histological, histomorphometric, and micro-computed tomography (micro-CT) analyses were performed. New bone formation was observed on the lateral and vertical sides of the mandible of all groups. Micro-CT and histomorphometry showed that the device+PRF group presented the highest percentages of bone volume and bone area at 4 weeks (56.67 ± 12.67%, 41.37 ± 7.57%) and at 8 weeks (49.67 ± 8.33%, 55.46 ± 10.67%; significantly higher than the other groups, P<0.001), followed by the device group at 4 weeks (33.00 ± 1.73%, 33.21 ± 11.00%) and at 8 weeks (30.00 ± 3.00%, 23.25 ± 5.46%). In conclusion, the modified Hyrax device was used successfully for OPD in a rabbit model to gain vertical ridge augmentation, and greater bone maturation was achieved with the addition of PRF.

  9. Biomechanical evaluation of maxillary Lefort Ι fracture with bioabsorbable osteosynthesis internal fixation.

    Science.gov (United States)

    Wu, Wei; Zhou, Jiang; Xu, Chong-Tao; Zhang, Jie; Jin, Yan-Jiao; Sun, Geng-Lin

    2014-12-01

    The aim of this study was to apply biomechanical analysis model to evaluate the effects of bioabsorbable internal fixation devices on maxillary Lefort Ι fracture. CT scan technology and the finite element software (ansys) were used to establish three-dimensional finite element models of five resorbable internal fixation devices in maxillary Lefort Ι fractures. We used the model to calculate the stress of the upper jaw and internal fixation. We further analyzed the stability of fixation under four occlusions. The fixation using two bioabsorbable plates was not stable. The zygomaticomaxillary pillars fixation is more stable than other fixations. The stability of fracture fixation was influenced with the molar occlusion. The current study developed a functional three-dimensional finite element model of bioabsorbable internal fixation and compared the stability of five fixation methods for maxillary Lefort Ι fractures. The results would facilitate the application of bioabsorbable materials in dental clinic.

  10. Objective and Subjective Outcome of a New Transcutaneous Bone Conduction Hearing Device

    DEFF Research Database (Denmark)

    Eberhard, Kristine Elisabeth; Olsen, Steen Østergaard; Miyazaki, Hidemi

    2016-01-01

    % at 50dB, by 34% at 65dB, and by 12% at 80 dB SPL. SRT50% in noise improved 5.2 dB. 58% of the patients used the device daily and 83% at least 5 days a week. 50% used the device ≥ 8 hours and 75% ≥ 4  hours a day. Mean International Outcome Inventory for Hearing Aids score was 3.7, corresponding...

  11. The Hopper: A Wearable Robotic Device Testbed for Micro-Gravity Bone-Loading Proof-of-Concept

    Science.gov (United States)

    Beck, C. E.; Rovekamp, R. N.; Neuhaus, P. D.

    2015-01-01

    Wearable robotic systems are showing increased potential for addressing crew countermeasures needs. Wearable robots offer a compactness, programmability, and eccentric loading capability not present in more conventional exercise equipment. Correspondingly, advancements in the man to machine interface has progressed, allowing for higher loads to be applied directly to the person in new and novel ways. Recently, the X1 exoskeleton, a lower extremity wearable robot originally designed for mobility assistance and rehabilitation, underwent human subject testing to assess its potential as a knee dynamometer. This was of interest to NASA physiologists because currently strength is not assessed in flight due to hardware limitations, and thus there is a poor understanding of the time course of in-flight changes to muscle strength. The study concluded that the X1 compared well with the Biodex, the "gold standard" in terrestrial dynamometry, with coefficients of variation less than 6.0%. In a following study, the X1 powered ankle was evaluated for its efficacy in exercising calf muscles. Current on-orbit countermeasures equipment does not adequately protect the calf from atrophy. The results of this study were also positive (targeted muscle activity demonstrated via comparing pre- and post-exercise magnetic resonance imaging T2 measurements), again showing the efficacy of wearable robotic devices for addressing the countermeasure needs of our astronauts. Based on these successes and lessons learned, the Grasshopper was co-developed between IHMC (Florida Institute for Human and Machine Cognition) and NASA. The Grasshopper, or the Hopper for short, is a wearable robotic device designed to address muscle and bone density loss for astronauts spending extended periods of time in micro-gravity. The Grasshopper connects to the user's torso like a hiking backpack, over the shoulders and around the waist. At the feet are footplates that strap to the user. There are two actuators, one

  12. Transosseous osteosynthesis with annular external fixator for the treatment of long bone defect after tibial traumatic%环形外固定架骨搬运治疗胫骨创伤后大段骨缺损

    Institute of Scientific and Technical Information of China (English)

    龙超; 刘炳胜; 王玮; 沈作佳

    2013-01-01

    Objective:To investigate the efficacy of the application of transosseous osteosynthesis with annular external fixator for the treatment of traumatic large bone defects of the tibia. Methods: From 2002 to 2011,17 cases of traumatic tibial long bone defect were treated by transosseous osteosynthesis with annular external fixator including 11 males and 6 females with an average age of (31.00±2.35) years old ranging from 22 to 45 years. The length of defect was from 5 to 13.1 cm with an average of (7.50+1.01) cm. The fixed time, bone healing time and the extend length of the affected limb were observed, and the degree of recovery of limb function after surgery were assessed ccording to the Paley's limb function evaluation. Results:All patients were followed up from 12 to 48 months with an average of (30.00±2.35) months,the bone defects of 17 patients achieved bone healing. The average bone healing time was (10.10±0.59) months (8 to 15 months) ;the average time of fixed time was (14.10±0.65 ) months (12 to 16 months) ;the average extend length of the affected limb was (7.50±1.01) cm. The results of Paley's functional evaluation was excellent in 9 cases,good in 6,fair in 2. Conclusion:Transosseous osteosynthesis with annular external fixator is an effective method for treatment of large bone defects of the tibia. It is successful reconstruction of limb length, simple operation, less soft tissue injury, and is clinical worthy of promotion.%目的:探讨应用环形外固定架辅助骨搬运术治疗创伤后胫骨大段骨缺损的疗效.方法:自2002年至2011年采用骨搬运术对17例创伤性胫骨长段骨缺损进行治疗,男11例,女6例;年龄22 ~45岁,平均(31.00±2.35)岁.骨缺损范围5~13.1 cm,平均(7.50±1.01) cm.观察外固定时间、骨性愈合时间、术后患肢延长长度.术后患肢功能恢复程度参照Paley评价标准进行功能评价.结果:全部病例获随访,时间12~48个月,平均(30.00±2.35)个月.17例

  13. Fiber-matrix interface studies on bioabsorbable composite materials for internal fixation of bone fractures. I. Raw material evaluation and measurement of fiber-matrix interfacial adhesion.

    Science.gov (United States)

    Slivka, M A; Chu, C C; Adisaputro, I A

    1997-09-15

    The objective of this study was to characterize and evaluate the performance of various fiber-matrix composite systems by studying the mechanical, thermal, and physical properties of the fiber and matrix components, and by studying the fiber-matrix interface adhesion strength using both microbond and fragmentation methods. The composites studies were poly(L-lactic acid) (PLLA) matrix reinforced with continuous fibers of either nonabsorbable AS4 carbon (C), absorbable calcium phosphate (CaP), poly(glycolic acid) (PGA), or chitin. Carbon and CaP single fibers had high Young's moduli and failed in a brittle manner. PGA and chitin single fibers had relatively lower Young's moduli and relatively higher ductility. Upon in vitro hydrolysis, CaP fibers retained 17% of their tensile strength and 39% of their Young's modulus after 12 h, PCA fibers retained 10% of their tensile strength and 52% of their Young's modulus after 16 days, and chitin fibers retained 87% of their tensile strength and 130% of their Young's modulus after 25 days. PLLA films had much lower strength and Young's moduli, but much higher ductility relative to the single fibers. Using the microbond method, the initial fiber-matrix interfacial shear strength (IFSS) of C/PLLA and CaP/PLLA microcomposites was 33.9 and 12.6 MPa, respectively. Upon in vitro hydrolysis, C/PLLA retained 49% of IFSS after 15 days and CaP/PLLA retained 46% of IFSS after 6 h. Using a fiber fragmentation method, the initial IFSS of C/PLLA, CaP/PLLA, and chitin/ PLLA was 22.2, 15.6, and 28.3 MPa, respectively. The performance of carbon fibers and C/PLLA composites was superior to the other fibers and fiber/PLLA systems, but the carbon fiber was nonabsorbable. CaP had the most suitable modulus of the absorbable fibers for fixing cortical bone fracture, but its rapid deterioration of mechanical properties and loss of IFSS limits its use. PGA and chitin fibers had suitable mechanical properties and their retention for fixing cancellous

  14. 一期后路病灶清除植骨融合内固定治疗胸椎结核%ONE-STAGE POSTERIOR DEBRIDEMENT, BONE GRAFT, AND INTERNAL FIXATION FOR THORACIC TUBERCULOSIS

    Institute of Scientific and Technical Information of China (English)

    陈宣维; 林建华; 陈雷; 陈飞; 许卫红; 韦超

    2011-01-01

    Objective To evaluate the clinical effectiveness and advantages of one-stage posterior debridement, bone graft, and internal fixation for thoracic tuberculosis. Methods The data were retrospectively analysed, from 21 cases of thoracic tuberculosis undergoing one-stage posterior debridement, bone graft, and internal fixation between June 2007 and November 2009. There were 16 males and 5 females with an average age of 42.2 years (range, 22-73 years). The average disease duration was 13.2 months (range, 7-21 months). The lesions were located at the level of T5,6 (1 case), T6,7 (1 case), T8,9 (4 cases), T9,10 (3 cases), Tio, n (5 cases), Tn, 12 (6 cases), and T9-11 (1 case). According to the Frankel grading criterion, the neurological function was rated as grade B in 2 cases, grade C in 6 cases, grade D in 10 cases, and grade E in 3 cases. The preoperative Cobb angle was (26.3 ± 9.2)°. The erythrocyte sedimentation rate (ESR) was (35.9 ± 11.2) mm/1 hour. Results Thoracic tuberculosis was confirmed in postoperative pathological examination in all 21 cases. All incisions healed primarily without fistules formation. The average follow-up time for 21 patients was 16.2 months (range, 1-3 years). Bony fusion was achieved within 7-12 months (mean, 9 months) without pseudoarthrosis. No loosening and breakage of internal fixation were found, and no local recurrence occurred. The ESR decreased to (25.1 ± 8.9) mm/1 hour at 1 week postoperatively, showing significant difference when compared with preoperative value (t=5.935, P < 0.01); it decreased to (14.1± 4.6) mm/1 hour at 3 months postoperatively. According to Frankel grade, the neurological function was significantly improved at 1 year after operation (x2=13.689, P=0.003). The average Cobb angle was (17.1 ± 4.5)° at 1 years postoperatively, showing significant difference when compared with preoperative value (t=7.476, P < 0.01). Conclusion One-stage posterior debridement, bone graft, and internal fixation has a

  15. Experimental assessment of a new direct fixation implant for artificial limbs.

    Science.gov (United States)

    Tomaszewski, P K; Lasnier, B; Hannink, G; Verkerke, G J; Verdonschot, N

    2013-05-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices. offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes considerable and progressive bone loss. To overcome this phenomenon a new concept of a direct fixation implant, in form of a collared metallic pin articulating inside a polymer intramedullary part, was developed. In this study we used experimental and finite element techniques to assess whether the novel concept produced a more physiological strain distribution in the bone as compared to a standard titanium implant. Cortical strains were measured experimentally on seven human cadaver femora, both intact and implanted with a generic standard implant and the new implant. Three load configurations were considered, simulating: heel strike, toe off and one leg stance. A finite element model derived from computed tomography data was used to calculate strains in intact bone and bone with generic models of the two implant types. Significant strain shielding occurred around both implant types, albeit that for the novel design strain shielding was generally less (ptransfemoral amputation.

  16. When Planning Screw Fracture Fixation Why the 5.5 mm Screw is the Goldilocks Screw. An Observational Computer Tomographic Study of Fifth Metatarsal Bone Anatomy in a Sample of Patients.

    Science.gov (United States)

    Iselin, Lukas D; Ramawat, Sunil; Hanratty, Brian; Klammer, Georg; Stavrou, Peter

    2015-05-01

    We wanted to verify our clinical experience that the 5.5 mm screw was ideal in the majority of fifth metatarsal fracture fixation. The size of a screw is important for the successful surgical treatment of these fractures in order to obtain the maximal stability while reducing the risk for iatrogenic fracture.A sample of patients undergoing computer tomographic imaging of the foot for investigation other than fifth metatarsal pathology were recruited. The parameters of the fifth metatarsal bone anatomy were measured.These parameters of the 5.5 mm screw were correlated with this data. The upper parameter (the diameter of the threads) was 5.5 and the lower parameter (the diameter of the shank) was 4.0 mm.Twenty seven patients were recruited.The proximal third internal diameter ranged from 3.6 to 7.0 mm with a mean of 5.0 mm. 93% of the metatarsals could easily accommodate the 5.5 mm screw. Two of the metatarsals had an internal diameter of < 4 mm (7%).It is our belief that the 5.5 mm screw may be used safely in the majority of patients with fifth metatarsal fractures.

  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 influence of bone formation on anchoring percutaneous devices with titanium fibre mesh flanges.

    NARCIS (Netherlands)

    Shalabi, M.M.; Walboomers, X.F.; Jansen, J.A.

    2004-01-01

    For man-made percutaneous devices (PD), it is known that anchoring will improve the clinical success. Previously, our Department has designed PDs that use a sheet of titanium (Ti) fibre mesh for anchoring. In nature, a very successful natural PD occurs, namely the tooth. Teeth are anchored in the al

  19. 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

  20. Hybrid approach of ventricular assist device and autologous bone marrow stem cells implantation in end-stage ischemic heart failure enhances myocardial reperfusion

    Directory of Open Access Journals (Sweden)

    Khayat Andre

    2011-01-01

    Full Text Available Abstract We challenge the hypothesis of enhanced myocardial reperfusion after implanting a left ventricular assist device together with bone marrow mononuclear stem cells in patients with end-stage ischemic cardiomyopathy. Irreversible myocardial loss observed in ischemic cardiomyopathy leads to progressive cardiac remodelling and dysfunction through a complex neurohormonal cascade. New generation assist devices promote myocardial recovery only in patients with dilated or peripartum cardiomyopathy. In the setting of diffuse myocardial ischemia not amenable to revascularization, native myocardial recovery has not been observed after implantation of an assist device as destination therapy. The hybrid approach of implanting autologous bone marrow stem cells during assist device implantation may eventually improve native cardiac function, which may be associated with a better prognosis eventually ameliorating the need for subsequent heart transplantation. The aforementioned hypothesis has to be tested with well-designed prospective multicentre studies.

  1. Prosthetic devices shaped as tubular chambers for the treatment of large diaphyseal defects by guided bone regeneration.

    Science.gov (United States)

    Nicoli Aldini, N; Fini, M; Giavaresi, G; Guzzardella, G A; Giardino, R

    2005-01-01

    Guided tissue regeneration is based on the hypothesis that the different tissues have unequal abilities to penetrate a wounded area during the healing process. The use of a device acting as a chamber allows the growth of a particular tissue and prevents the ingrowth of other tissues which impair the healing process. At the same time the chamber protects and maintains in situ the intrinsic growth factors so that they may perform their specific activity. Guided tissue regeneration currently plays a well-recognized role mostly in dentistry and peripheral nerve surgery but interesting perspectives have also opened up in orthopedics. Considering the possibility of using guided bone regeneration in the repair of diaphyseal bone defects, this updated survey highlights some critical points and pathways related to the state-of-the-art of this promising procedure, focusing particularly on the properties of the material to make the tubular chamber, the use of osteopromotive factors and the most appropriate animal model to be used for the experimental evaluation.

  2. Orthopedic intrusion of premaxilla with distraction devices before alveolar bone grafting in patients with bilateral cleft lip and palate.

    Science.gov (United States)

    Liou, Eric Jein-Wein; Chen, Philip K T; Huang, C Shing; Chen, Y Ray

    2004-03-01

    Surgical repositioning of the downward displaced premaxilla in bilateral cleft lip and palate patients remains a controversial and perplexing issue because of its detrimental effects on the growth of the premaxilla. The purpose of this prospective clinical study was to introduce and evaluate the treatment results of an innovative technique for nonsurgically intruding the downward displaced premaxilla. Eight consecutive cases of bilateral cleft lip and palate at the age of mixed dentition were included for the correction of their premaxillary deformities. A pair of intraoral tooth-borne distraction devices was used for the orthopedic intrusion. Serial lateral and posteroanterior cephalometric radiographs were taken periodically for evaluating the growth of the premaxilla 1 year before the intrusion, changes during the intrusion, and growth/relapse up to 1 year after the intrusion. There was no overgrowth of the premaxilla or overeruption of the maxillary incisors during the 1-year observing period before the orthopedic intrusion. The treatment results revealed that the downward displaced premaxillae were all corrected within 1 month. Cephalometrically, 46 percent of the correction resulted from a true orthopedic intrusion and another 54 percent from a dentoalveolar effect in which the maxillary incisors were intruded and the premaxillary dentoalveolus was shortened. The cephalometric evaluations also implied that what occurred during the orthopedic intrusion was mostly the sutural contraction osteogenesis/osteolysis in the vomeropremaxillary suture combined with slightly mechanical upward displacement of the vomeronasal septum complex and nasal bones. The orthopedic intrusion of the premaxilla with distraction devices is an effective nonsurgical method for correcting the downward displaced premaxilla before alveolar bone grafting in patients with bilateral cleft lip and palate, and the results remained stable after 1 year.

  3. Tibial inlay press-fit fixation versus interference screw in posterior cruciate ligament reconstruction

    Directory of Open Access Journals (Sweden)

    Max Ettinger

    2013-11-01

    Full Text Available Reconstruction of the posterior cruciate ligament (PCL by a tibial press-fit fixation of the patellar tendon with an accessory bone plug is a promising approach because no foreign materials are required. Until today, there is no data about the biomechanical properties of such press-fit fixations. The aim of this study was to compare the biomechanical qualities of a bone plug tibial inlay technique with the commonly applied interference screw of patellar tendon PCL grafts. Twenty patellar tendons including a bone block were harvested from ten human cadavers. The grafts were implanted into twenty legs of adult German country pigs. In group P, the grafts were attached in a press-fit technique with accessory bone plug. In group S, the grafts were fixed with an interference screw. Each group consisted of 10 specimens. The constructs were biomechanically analyzed in cyclic loading between 60 and 250 N for 500 cycles recording elongation. Finally, ultimate failure load and failure mode were analyzed. Ultimate failure load was 598.6±36.3 N in group P and 653.7±39.8 N in group S (not significant, P>0.05. Elongation during cyclic loading between the 1st and the 20th cycle was 3.4±0.9 mm for group P and 3.1±1 mm for group S. Between the 20th and the 500th cycle, elongation was 4.2±2.3 mm in group P and 2.5±0.9 mm in group S (not significant, P>0.05. This is the first study investigating the biomechanical properties of tibial press-fit fixation of the patellar tendon with accessory bone plug in posterior cruciate ligament reconstruction. The implant-free tibial inlay technique shows equal biomechanical characteristics compared to an interference screw fixation. Further in vivo studies are desirable to compare the biological behavior and clinical relevance of this fixation device.

  4. Three Dimensional Finite Element Analysis of Stress Distribution and Displacement of the Maxilla Following Surgically Assisted Rapid Maxillary Expansion with Tooth- and Bone-Borne Devices

    Directory of Open Access Journals (Sweden)

    Mohsen Dalband

    2015-10-01

    Full Text Available Objectives: The aim of this study was to investigate the displacement and stress distri- bution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices.Materials and Methods: Three-dimensional (3D finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five CAD models were simulated as fol- lows and surgical procedures were used:  G1: control group (without surgery; G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation.Results: Maxillary displacement showed a gradual increase from group 1 to group 5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-me- dian osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth.Conclusion: Combination of Le Fort I and para-median osteotomy with pterygomaxil-lary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

  5. Bone and muscle structure and quality preserved by active versus passive muscle exercise on a new stepper device in 21 days tail-suspended rats.

    Science.gov (United States)

    Sun, L W; Blottner, D; Luan, H Q; Salanova, M; Wang, C; Niu, H J; Felsenberg, D; Fan, Y B

    2013-06-01

    Human performance in microgravity is characterized by reversed skeletal muscle actions in terms of active vs. passive mode contractions of agonist/antagonist groups that may challenge principal biodynamics (biomechanical forces translated from muscle to bone) of the skeletal muscle-bone unit. We investigated active vs. passive muscle motions of the unloaded hindlimb skeletal muscle-bone unit in the 21 days tail-suspended (TS) rat using a newly designed stepper exercise device. The regimen included both active mode motions (TSA) and passive mode motions (TSP). A TS-only group and a normal cage group (CON) served as positive or negative controls. The muscle and bone decrements observed in TS-only group were not seen in the other groups except TSP. Active mode motions supported femur and tibia bone quality (5% BMD, 10% microtrabecular BV/TV, Tb.Th., Tb.N. parameters), whole soleus muscle/myofiber size and type II distribution, 20% increased sarcolemma NOS1 immunosignals vs. CON, with 25% more hybrid fiber formation (remodeling sign) for all TS groups. We propose a new custom-made stepper device to be used in the TS rat model that allows for detailed investigations of the unique biodynamic properties of the muscle-bone unit during resistive-load exercise countermeasure trials on the ground or in microgravity.

  6. 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.

  7. 儿童前臂双骨折选择髓内钉固定还是切开复位钢板内固定?%Both-bone forearm fractures in children Intramedullary nailing or open reduction with plate fixation?

    Institute of Scientific and Technical Information of China (English)

    Joseph R Dettori; 王簕; 杨云峰

    2011-01-01

    Six small retrospective cohort studies shed little light on whether intramedullary nailing (IMN) or open reduction internal fixation (ORIF) with plate fixation is more effective in treating both-bone forearm fractures in children. No statistically significant difference between treatment groups was found with regard to functional outcomes or the average magnitude of radial bowing.Small sample sizes may have precluded detection of statistically significant differences. In one study, a statistically significant difference was found in the average radial bow location in the IMN group as compared with both the ORIF group and normative values. Cosmetically,IMN provided significantly better results (ie, smaller incision/scar length) than ORIF as assessed by two studies. For both nonunion/delayed healing and complications, rates varied widely between studies and did not consistently favor one treatment method over the other. Randomized controlled studies with larger sample sizes and longer follow-up periods are needed to determine which treatment option is optimal. Use of validated outcomes measures is recommended.%@@ 根据6项小样本回顾性队列研究的结果,在评价髓内钉固定(IMN)和切开复位钢板内固定(ORIF)治疗儿童前臂双骨折的疗效时证据较弱.研究结果显示,在患肢功能和桡骨弓的恢复方面,两种治疗方法差异无统计学意义.由于样本量较小,本身就排除了产生统计学差异的可能性.一项研究显示,IMN组桡骨弓的顶点位置与ORIF组相比差异均有统计学意义.2项研究认为,与ORIF组相比,IMN组术后结果更好(如手术切口、瘢痕更小).在骨折不愈合或延迟愈合和并发症发生率方面,各研究结论不一,无法说明哪种方法更优.综上所述,仍需大样本的随机对照研究并进行长期随访,采用有效的评价方法,以便更好地评价哪种治疗方法更好.

  8. 前方入路病灶清除植骨融合内固定治疗颈胸段结核%Debridement and bone grafting with internal fixation via the anterior approach for treatment of cervicothoracic tuberculosis

    Institute of Scientific and Technical Information of China (English)

    蓝旭; 许建中; 刘雪梅; 葛宝丰

    2012-01-01

    Objective:To investigate the outcome of radical debridement,reconstruction with bone autograft or allograft and plate internal fixation via the anterior approach for the treatment of cervicothoracic tuberculosis. Methods: From Jun. 2000 to Dec. 2010,20 patients with cervicothoracic tuberculosis were treated by debridement and bone grafting with internal fixation via the anterior approach. They included 17 males and 3 females who ranged in age from 25 to 46 years (mean 38 years). The course of disease ranged from 3 months to 2 years (mean 12 months). The onset of the disease was chronic in all patients,with main complaints of persistent pain, and cervical stiffness and deformity accompanied with low fever, night sweating and pathologic leanness. Preoperative X-ray,CT or MRI showed that the pathologic change occurred in C7-T| segment in 10 cases,T, segment in 6 cases,T1-T3 segment in 3 cases, and T2-T3 segment inl case. The Cobb angle ranged from 25?to 60?mean 35? before surgery. The Frankel classification was as follows:2 cases at grade A,4 cases at grade B,7 cases at grade C,2 cases at grade D,and 5 cases at grade E. All the patients underwent a standard cervical approach by combined partial median steotomy and transverse steotomy through the aynostosis between the manubrium and body of the sternum to expose the lesion adequately. Radical debridement was performed ,and then a tricortical iliac crest bone autograft or allograft was placed and secured by internal fixation to reconstruct the spinal column. The change in Cobb angle and fusion of bone grafting were reexamined by X-ray regularly. The clinical symptoms and neurological function were evaluated according to NDI (neck disability index) score and Frankel classification. Results:There was no injury to blood vessels,spinal cord or recurrent nerve during surgery. All patients were followed-up from 16 to 39 (mean 25) months. The tuberculosis symptoms disappeared after surgery and there was no tuberculosis

  9. Photographic fixative poisoning

    Science.gov (United States)

    Photographic developer poisoning; Hydroquinone poisoning; Quinone poisoning; Sulfite poisoning ... Quinones Sodium thiosulfate Sodium sulfite/bisulfite Boric acid Photographic fixative can also break down (decompose) to form ...

  10. Functionalized bridged silsesquioxane-based nanostructured microspheres: performance as novel drug-delivery devices in bone tissue-related applications.

    Science.gov (United States)

    Romeo, Hernán Esteban; Fanovich, María Alejandra

    2012-05-01

    Two kinds of functionalized nanostructured hybrid microspheres, based on the bridged silsesquioxane family, were synthesized by employing the sol-gel method via self-assembly of two different organic-inorganic bridged monomers. The architecture reached at molecular level allowed the incorporation of acetylsalicylic acid (ASA) as an anti-inflammatory model drug. The ASA-functionalized microspheres were characterized as delivery devices in simulated body fluid (SBF). The release behaviors of the synthesized microspheres (Fickian or anomalous diffusion mechanisms) were shown to be dependent on the chemical nature of the bridged monomers employed to synthesize the hybrid materials. The functionalized microspheres were proposed as delivery systems into calcium phosphate cements (CPCs), in order to slow down the characteristic drug-delivery kinetics of this kind of bone tissue-related materials. The incorporation of the new functionalized microparticles into the CPCs represented a viable methodology to modify the ASA-release kinetics in comparison to a conventional CPC containing the drug dispersed into the solid phase. The ASA-delivery profiles obtained from the microsphere-loaded CPCs showed that 40-60% of drug can be released after 2 weeks of testing in SBF. The inclusion of the microspheres into the CPC matrices allowed modification of the release profiles through a mechanism that involved two stages: (1) the diffusion of the drug through the organic-inorganic matrix of the microspheres (according to a Fickian or anomalous diffusion, depending on the nanostructuring) and (2) the subsequent diffusion of the drug through the ceramic matrix of the hardened cements. The release behavior of the composite cements was shown to be dependent on the nanostructuring of the hybrid microspheres, which can be selectively tailored by choosing the desired chemical structure of the bridged precursors employed in the sol-gel synthesis. The obtained results demonstrated the ability of

  11. 探讨后路椎间盘摘除椎弓根钉内固定结合Cage植骨治疗腰椎间盘突出症的临床效果%Clinical Effect of Posterior Lumbar Interbody Fusion and Pedicle Screw Fixation Combined With Cage Bone Graft in the Treatment of Lumbar Disc Herniation

    Institute of Scientific and Technical Information of China (English)

    梁涛

    2016-01-01

    Objective To explore the feasibility of posterior lumbar interbody fusion and pedicle screw fixation combined with Cage bone graft in the treatment of lumbar disc herniation. Methods 86 patients with lumbar disc herniation were col ected. The patients in the study group were treated with posterior lumbar interbody fusion and pedicle screw fixation combined with Cage bone graft. The control group was treated with simple bone graft. Results There were significant differences in the treatment effect of the two groups after 6 months. Conclusion The treatment of lumbar disc herniation by posterior lumbar interbody fusion with pedicle screw fixation combined with Cage bone graft is effective and safe.%目的:探究腰椎间盘突出症使用后路椎间盘摘除椎弓根钉内固定结合 Cage 植骨治疗的可行性。方法收集腰椎间盘突出症患者86名,研究组使用后路椎间盘摘除椎弓根钉内固定结合 Cage 植骨治疗方案,对照组使用单纯植骨治疗方案。结果术后6个月两组患者治疗效果的差异具有统计学意义。结论腰椎间盘突出症使用后路椎间盘摘除椎弓根钉内固定结合 Cage 植骨治疗,具有较高的有效率和安全性。

  12. Femoral Aperture Fixation Improves Anterior Cruciate Ligament Graft Function When Added to Cortical Suspensory Fixation

    Science.gov (United States)

    Porter, Mark D.; Shadbolt, Bruce

    2016-01-01

    Background: Recommendations for bone tunnel placement during anterior cruciate ligament (ACL) reconstruction have become more precise. However, these recommendations differ neither with the choice of graft nor with the method of fixation used. The influence of the method of femoral fixation used on the biomechanical function of a soft tissue ACL graft remains unknown. Hypothesis: Our null hypothesis was that adding femoral aperture fixation to femoral cortical fixation, using the same bone tunnels, will not alter the control of anterior translation (AT) and internal rotation (IR) during ACL reconstruction using a hamstring graft. Study Design: Controlled laboratory study. Methods: A total of 22 patients with an acute isolated ACL rupture underwent reconstruction using a single-bundle autologous hamstring graft. Computer navigation was used intraoperatively to plot the AT and IR during the pivot-shift test before reconstruction, after ACL reconstruction using cortical suspensory fixation, and after the addition of femoral aperture fixation. Statistical analysis (analysis of variance) was used to compare the AT and IR during the pivot shift at each stage in the procedure. Results: Before ACL reconstruction, the mean (±SD) AT was 14.2 ± 7.3 mm and mean IR was 17.2° ± 5.5°. After reconstruction using femoral cortical suspension, these figures were significantly reduced to 6.2 ± 3.5 mm and 12.5° ± 3.20°, respectively (P < .001). The addition of the aperture fixation was associated with a further significant reduction to 4.6 ± 3.2 mm and 10.4° ± 2.7°, respectively (P < .001). Conclusion: The addition of femoral aperture fixation to suspensory fixation results in a significant reduction in both the AT and IR that occurs during the pivot-shift assessment immediately after ACL reconstruction using autologous hamstring graft. Clinical Relevance: The most precise positioning of bone tunnels during soft tissue ACL reconstruction needs to take into consideration

  13. Comparison of the effect of transplantation of fibula flap with vascular pedicle vs. Ilizarov external fixation in the treatment of nonunion of tibial bone defect%带血管蒂的腓骨瓣移植和Ilizarov外固定骨牵引术治疗胫骨骨缺损骨不连的比较

    Institute of Scientific and Technical Information of China (English)

    陈时高; 孙军锁; 景斗星; 蔡雅楠; 杨森; 王铁涛

    2016-01-01

    Objective To analyze and compare the curative effect of transplantation of fibula flap with vascular pedicle vs. Ilizarov external fixation in the treatment of nonunion of tibia bone defect. Methods The clinical data of 64 patients with nonunion of tibial bone defect from May 2009 to May 2013 were analyzed retro-spectively. From May 2009 to April 2012, 30 patients were given Ilizarov external fixation and bone traction therapy (bone traction group); from May 2012 to May 2013, 34 patients were subjected to vascularized fibula flap transplantation (fibula flap transplantation group). The medical indicators and Johner-Wruhs tibial shaft fracture efficacy evaluation criteria were compared between two groups. Results As compared with fibula flap transplantation group, operative time and hospital stay were significantly shortened in bone traction group ( P0.05). The healing time was significantly reduced in the fibula flap transplantation group as compared with bone traction group (P0.05).治疗后的Johner-Wruhs评分,腓骨瓣移植术组优良率为82.4%(28/34),骨牵引术组为60.0%(18/30),差异有统计学意义(P<0.05).结论 对比Ilizarov外固定骨牵引术,带血管蒂的腓骨瓣移植术治疗胫骨骨缺损骨不连患者具有骨折愈合时间短、疗效更佳的特点,但是其手术时间以及住院时间均显著延长.

  14. 两种不同内固定材料和植骨材料治疗胸腰椎椎体骨折的疗效分析%Effect of two different internal fixation and bone graft on patients with thoracic or lumbar spinal fracture

    Institute of Scientific and Technical Information of China (English)

    孟新文; 边江; 禹晓东

    2011-01-01

    目的:研究经后路复位内固定并行伤椎植骨对胸、腰椎骨折的治疗效果.方法:对椎体压缩性骨折和爆裂性骨折使用AF或钉棒系统复位固定后,经伤椎椎弓根向伤椎植入自固化磷酸钙人工骨和同种异体骨的治疗结果进行分析.结果:治疗432例 468椎,手术后椎体高度即刻恢复100%的319椎;95%以上80椎;90%以上60椎;80%以上的9椎.398例获得随访,随访10月~8年,伤椎均获得骨性愈合,脊柱稳定性及运动功能恢复良好.结论:胸、腰椎椎体骨折经AF或钉棒系统复位固定后,伤椎植入自固化磷酸钙人工骨和同种异体骨的疗效确切,效果优良.%Objective:To investigate the effect of two different internal fixation system and bone graft on patients with thoracic or lumbar spinal fracture. Methods: From April,2001 to June,2008, 468 body of vertebral in 432 patients suffered from compression fracture or blowout fracture were randomly selected to be treated with AF fixation system and screw - baculum fixation system, then artificial bone of calcium acid phosphate and homogeneity bone were transplanted into the vertebral body of fracture through neck of vertebra. Postoperatively, radiographic finding and clinical results were observed. Results: Instantly after operation, the height of 319 vertebral body were recovered completely ( 100% ), 80 recovered 95%, 60 recovered 90% and 9 recovered 80%. A total of 398 patients were followed - up after surgery, ranging from 10 months to 8 years. Radiographs showed all patients have got the bone union, the movement function of spine was significantly relieved and none suffered from low back pain or radicular pain. Neither complications nor instrumentation failure were observed. Conclusion:Internal fixation system and transplantation of bone graft through neck of vertebra could be recommended for treatment of thoracic or lumbar spinal fracture.

  15. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  16. Principles of intramedullary pin and wire fixation.

    Science.gov (United States)

    Howard, P E

    1991-02-01

    Knowledge and experience in the proper use of IM pins, K-wires, and orthopedic wire is a valuable asset to the veterinarian's ability to successfully repair a variety of long bone fractures. Most long bone fractures are amenable to repair with this form of fixation. When the principles of application are violated or the implants are used when contraindicated, complications often occur. Proper use of these implants results in the successful management of complex fractures to the satisfaction of both the animal owner and the veterinarian (Fig 10).

  17. The effect of latency on bone lengthening force and bone mineralization: an investigation using strain gauge mounted on internal distractor device

    Directory of Open Access Journals (Sweden)

    Wang Jue

    2006-03-01

    Full Text Available Abstract Background The purpose of this study was to investigate the effect of latency on the development of bone lengthening force and bone mineralization during mandible distraction osteogenesis. Methods Distraction tensions were investigated at different latency period in 36 rabbits using internal unilateral distractor. Strain gauges were prepared and attached to the distractor to directly assess the level of distraction tension during mandible lengthening. The tensile force environment of the mandible of rabbit during distraction was evaluated through in vivo experiments using two gauges. The animals were divided into 3 groups each containing 12 rabbits. Latency periods of 0, 4 and 7 days respectively were observed prior to beginning distraction. The distraction protocol consisted of a lengthening rate of 1 mm once daily for 8 days, followed by a consolidation phase of 2 weeks after which the animals were killed. Biopsies specimens were taken from the distracted area at the end of the distraction period. A non-distracted area of the mandible bone served as control. The specimens were analyzed by scanning electron microscopy to assess the ultrastructural pattern, and the bone mineralization. Results The resting tension acting on the distraction gap increases through distraction. The 7-day latency groups exhibit higher tension then those of 0-day and 4-days latency groups. Quantitative energy dispersive spectral analysis confirmed that immediate distractions were associated with lower calcium and phosphate atomic weight ratio. Conclusion the latency periods could affect the bone lengthening tension and the bone mineralization process.

  18. Choice of the loading stress during the fracture fixation of humerus using Swain Memory Compression Bone Reduction Apparatus%天鹅记忆加压接骨器对肱骨骨折加载应力的选择

    Institute of Scientific and Technical Information of China (English)

    苏佳灿; 王瑞官; 张春才; 薛召军; 吴建国; 丁祖泉

    2005-01-01

    背景:肱骨骨折治疗中经常遇到的主要问题在于应力加载的方向与应力加载的力值.目的:分析天鹅记忆加压接骨器固定肱骨时不同应力加载的选择,为今后肱骨骨折治疗时内固定器械的放置部位、载荷的施加方向及大小等提供力学依据.设计:进行不同应力加载的条件下,构建肱骨骨折的三维有限元模型.单位:解放军第二军医大学附属长海医院骨科和同济大学生命科学与生物工程学院.材料:实验于2001-01/2003-05在解放军第二军医大学长海医院骨科实验室和同济大学生命科学与生物工程学院实验室完成.选取湿成年尸体肱骨标本和与之相对应型号的天鹅型记忆接骨器.方法:选择湿肱骨标本行CT成像得到肱骨每层横截面图像,采用大型有限元分析软件ANSYS 5.6建立肱骨、天鹅型记忆接骨器以及天鹅型记忆接骨器固定肱骨的三维模型.主要观察指标:对比不同加载方式下肱骨的受力情况,寻求临床治疗的参考数值.结果:所构建天鹅型记忆接骨器固定肱骨三维模型,逼真反映真实解剖形态及生物力学行为,同时获得不同加载方式下肱骨的受力情况.结论:天鹅型记忆接骨器固定肱骨三维有限元模型的构建,可以为肱骨正常力学行为以及骨折后内固定的力学基础研究提供精确模型.%BACKGROUND: During the therapy of the fracture of humerus, the main problem is the loading direction and power of the stress.OBJECTIVE: To analyze the choice of the different loading manners using Swain Memory Compression Bone Reduction Apparatus so as to provide the clinical evidence for the set position of the internal fixation apparatus, the loading direction and power during the therapy of the fracture of humerus.DESIGN: To construct the three-dimensional finite element model of the fracture of humerus with different loading manners.SETTING: Department of Orthopaedics of Changhai Hospital of

  19. 病灶清除植骨内固定加灌注冲洗局部化疗治疗胸腰椎结核24例临床分析%Debridement Bone Graft and Internal Fixation with Irrigation and Local Chemotherapy in the Treatment of Thoracic and Lumbar Tuberculosis:Clinical Analysis of 24 Cases

    Institute of Scientific and Technical Information of China (English)

    王剑龙; 孙建锋

    2013-01-01

    Objectives To summary the curative effect of lesion clearance , bone transplantation internal fixation ,local chemotherapy and persistent local drainage on spinal tuberculosis. Methods 24 cases of spinal tuberculosis with abscess, all given systemic chemotherapy, were accepted lesion clearance, posterior (anterior) internal fixation ,auto-iliac bone graft, placing perfusion tube for local drainage and putting into a epidural catheter for local chemotherapy. Results 24 cases of spinal tuberculosis with abscess ,followed up for 6 months to 30 months, of which 23 cases had satisfactory effects,had no relapse ,had stable internal fixation without fixation relaxation and fracture, and got solid fusion within 6 months .Only one case occurred wound dehiscence one month after the surgery , and healed after debridement and wound dressing . Conclusion The curative effect of lesion clearance , bone transplantation internal fixation ,local chemotherapy and persistent local drainage had obvious effect in treatment of spinal tuberculosis. Lesion clearance bone transplantation internal fixation could effectively correct the spine deformity, stabilize the spine,promote spinal bone transplantation crasis, shorten in-bed time, walk as soon as possible,reduce complications. local chemotherapy and persistent local drainage could clear the focus away thoroughly,reduce the chance of relapse.%  目的总结病灶清除植骨内固定术加置管灌注冲洗局部化疗治疗脊柱结核的疗效。方法24例脊柱结核并脓肿患者,全部患者在全身化疗的同时,采用病灶清除(前路),后路(或前路)内固定,取髂骨植骨,病灶部位放置灌注冲洗管进行灌注冲洗和持续局部化疗,并同时置一硬膜外导管于体外,局部注射抗结核药物。结果24例脊柱结核并脓肿患者经过6~30个月随访,其中1例术后1个月出现伤口裂开,清创换药20天后痊愈。余23例疗效满意,无结核复发。所

  20. 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......The use of bone grafting is a well-established way to enhance initial implant fixation in situations with reduced bone stock. Ceramic bone substitutes are inferior alternatives to autogenous or allogeneic bone graft. Improvement of bone graft substitutes is needed. We investigated whether...

  1. 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

  2. Development of the fixation device matching small animals and the clinical gamma knife stereotactic frame%适配小型动物及临床伽玛刀立体定向头架固定装置的研制

    Institute of Scientific and Technical Information of China (English)

    耿明英; 姚一博; 沈光建; 许民辉; 李飞鹏; 唐琳; 刘俊红; 周小琴

    2013-01-01

    Objective In order to meet the need of experimental study for gamma knife radiosurgery with small animals, the fixation device matching small animals and clinical gamma knife stereotactic frame was developed. Methods The high-strength nonmagnetic organic glass was used as base material for the device,and posterior fixed poles from gamma knife stereotactic frame as the foundation of fixation. Its structure included animal tray, matching fixing feet and ear-head fixation device consisting of fixed-eat part and fixed-head part. Results In a test of accuracy with Wistar rats, errors in the X, Y, Z direction of (0. 15 ± 0. 27) mm, (0. 27 ± 0. 33)mm, (0. 26 ± 0. 42)mm respectively were observed. Then 128 Wistar rats were radiated by gamma knife with the fixation device,and unfixed rate was 3. 7% and mortality rate was 5. 2%. Conclusion These results indicate that the fixation device meet design requirements,and provide convenience for the experimental study about gamma knife radiosurgery.%目的 为了满足小型动物伽玛刀放射外科实验研究的需要,设计和研发一种小型动物和临床伽玛刀立体定向头架的固定装置.方法 该装置取材于高强度无磁性有机玻璃,由动物托盘、适配固定脚、耳和头齿固定等部件组成,以伽玛刀立体定向框架后组支杆作为固定.结果 用Wistar大鼠验证了本适配装置的准确性.在X、Y、Z方向的平均误差分别为(0.15±0.27)、(0.27±0.33)、(0.26±0.42)mm.应用本装置对128只Wistar大鼠进行了伽玛刀照射,动物失固定率为3.7%,死亡率5.2%,其余动物均准确投照于目标点.结论 该适配固定装置达到了设计要求,为伽玛刀放射外科的实验研究提供了便利条件.

  3. Treatment of thoracolumbar fractures with vertebral body bone graft through pedicle and transpedicular fixation via fractured vertebra%伤椎置钉并椎体内植骨内固定术在胸腰椎骨折治疗中的应用

    Institute of Scientific and Technical Information of China (English)

    秦入结; 宋波; 李垠; 盛路新; 刘建; 孙晓

    2012-01-01

    目的 观察伤椎置钉并椎体内植骨内固定术在胸腰椎骨折治疗中的应用效果.方法 至少一侧椎弓根完整的胸腰椎骨折26例,予伤椎撬拨复位置钉、椎体内植骨、椎弓根内固定,据胸腰段正侧位片比较术前、术后即刻、术后6个月的椎体高度及Cobb's角,并评估脊髓神经功能和融合情况.结果 术后随访7~28个月.患者术后即刻伤椎椎体前缘高度占正常高度百分比及Cobb's角优于术前(P均<0.05);伤椎外形恢复满意;按ASIA脊髓神经功能分级,伴神经损伤者15例中,A级1例无恢复,余均改善1~3级(P均<0.05),内固定无失效,植骨皆融合.结论 伤椎置钉并椎体内植骨内固定术治疗胸腰椎骨折可重建椎体结构,增强脊柱稳定,近期疗效较好.%Objective To observe the outcome of vertebral body bone grafting throughpedicle combined with transpedicular fixation via fractured vertebra in the treatment of thoracolumbar fractures, and explore the operation methods. Methods 26 cases of thoracolumbar fractures, which had at least one side pedicle complete , were treated with posterior pedicle fixation by leverage, bone graft through pedicle and transpedicular fixation via fractured vertebra. According to the data of thoracolumbar radiograph, the anterior vertebral height and Cobb's angle of preoperation, postoperation instantly and after 6 monthswere compared. Their fusion results and neurological functions were observed. Results The follow-up period was 7 to 28 months . There were significant differences in the percentage of anterior vertebral height to the normal and Gobb's angle between preoperation and postoperation instantly (all P <0. 05). The shape of injured vertebra were restored satisfactorily . The spinal cord function was classified by ASIA's scale, it was improved 1 to 3 degree in all cases( 15 cases) of pre-operative neurological injury except of one case of grade A (all P < 0. 05). There was no case of fixation

  4. Removal of lumbar disc with cage bone graft fusion and internal fixation for the treatment of lumbar disc herniation%腰椎间盘摘除加cage植骨融合内固定治疗腰椎间盘突出症

    Institute of Scientific and Technical Information of China (English)

    张亚; 冯虎; 李健华; 刁天月; 蒋学军; 杨挺

    2016-01-01

    目的:探讨腰椎间盘摘除加cage植骨融合内固定治疗腰椎间盘突出症的临床疗效。方法对32例腰椎间盘突出症患者行腰椎间盘摘除加cage植骨融合内固定术,采用Oswestry功能障碍指数( ODI)和疼痛视觉模拟评分( VAS)对手术疗效进行评估。结果患者均获得随访,时间12~36(18±6.5)个月。患者术后疼痛均明显缓解,功能改善,术后ODI与VAS评分均较术前明显降低,差异有统计学意义( P<0.05)。术后融合节段均骨性愈合。随访期间内cage位置正常,内固定物无断裂及滑脱。结论腰椎间盘摘除加cage植骨融合内固定术能增加脊柱的稳定性及脊柱融合率,缓解患者症状及改善功能,临床疗效满意。%Objective To investigate the clinical effect of removal of lumbar disc with cage bone graft fusion and in-ternal fixation for the treatment of lumbar disc herniation. Methods 32 patients with lumbar disc herniation who un-derwent removal of lumbar disc with cage bone graft fusion and internal fixation systems. Oswestry disability index ( ODI) and visual analogue scale ( VAS) were used to evaluate the surgical effect. Results All patients were fol-lowed up for 12 ~36 ( 18 ± 6. 5 ) months. The postoperative pain was significantly relieved and function was im-proved, postoperative ODI and VAS decreased significantly comparing with that of the preoperation (P<0. 05). All fusion segments achieved solid fusion, all these implants were in good places without displacement or internal fixation failure. Conclusions Removal of lumbar disc with cage bone graft fusion and internal fixation for the treatment of lumbar disc herniation can increase the stability of the spine and the rate of fusion, significantly relieve symptoms and improve patients′function, which can obtain a satisfactory clinical effect.

  5. Plate fixation of paediatric fractures of the distal tibia and fibula.

    Science.gov (United States)

    He, Bingshu; Wang, Jun

    2012-10-01

    The role of surgery in the management of paediatric long-bone shaft fractures remains a matter of debate. We present a series of paediatric patients with unstable fractures of the distal tibia and fibula, treated with titanium plate fixation. Excellent results were obtained after plate fixation.

  6. Tne stiffness of first-order and second-order modules assembled with extracortical clamp devices

    Directory of Open Access Journals (Sweden)

    F. K. Sabirov

    2015-01-01

    Full Text Available The extracortical clamp device (ECD is a tool used in external fixation which unlike the K-wires and half-pins don’t perforate cortical bone. The use of ECD is prospective for the treatment of periprosthetic femoral fractures and in the lengthening over nail and bone transport over nail. The data on the bench tests of the osteosynthesis rigidity by the external fixation first-order and second-order modules on the base of extracortical clamp devices are observed in the article. Materials and methods. The authors made 240 bench tests using torsional-vibration machine, Indicators measuring linear displacements with a scale of 0.01 mm, bone simulators («Sawbones», calibrated load, Ilizarov’s apparatus и extracortical fixators. The statistical analysis was performed with use software «STATISTICA» (ver. 6.0. The data obtained are presented in graphs «Box and Whisker Plot». Results. Among the investigated variants of first-order modules the better results of osteosynthesis rigidity were found in the module based on two ECD inserted at angle 60 degrees to each other and at distance of 10 cm from each other. Among the investigated second-order modules, better results of osteosynthesis rigidity were found in the module based on two ECD inserted at an angle 60 degrees to each other at distance of 10 cm from each other. Conclusion. Thus the tested modules can be used in practice in assemblies of external fixation devices in periprosthetic fractures, lengthening and bone transport over the nail.

  7. 后路经伤椎植骨内固定治疗胸腰椎骨折的疗效分析%Effect of Posterior Vertebral Bone Graft Internal Fixation for the Treatment of Thoracic and Lumbar Fracture Analysis

    Institute of Scientific and Technical Information of China (English)

    曾德清; 熊福生; 万仲贤; 喻刚; 廖华; 吴威甫

    2015-01-01

    Objective To observe the ef icacy,indication and clinical outcome of fixation via injured vertebra for the treatment of thoracolumbar fracture.Methods From March 2012 to March 2014,30 patients with thinacolumbar fracture underwent surgical procedure of reduction and pediele screw at the fracture level,X-rays and CT scans were performed after operation,Cobb angle of the injured vertebral segment,the percentage of vertebral compression,and sagit al diameter stenosis rate of the injured spinal canal were observed for radiographic evaluation.Neurological function was evaluated by the Frankel scale.Results Al patients were fol1owed-up from 12 to 36 months.There was no pseudoarticulation,solid bone fusion was achieved in al cases.Cobb angle of the injured vertebral segment was cor ected from preoperative (25.6±9.7)degree to postoperative (9.1±4.1)degree and (10.2±4.7)degree at last fol ow-up.The percentage of vertebral compression was cor ected from preoperative (48.3±10.1)%to postoperative(6.5±3.2)%and(7.5±3.7)%at last fol ow-up.Spinal canal sagit al diameter stenosis rate was cor ected from preoperative(36.9±11.2)%to postoperative(6.3±4.7)%and(6.4±4.5)%one year after operation.The spinal cord function was improved 1 to 2 degree in al patients except 1 patients of grade A.Conclusion Indirect reduction and fixation with pedicle screw to treat thoracolumbar vertebral fracture have several advantages:less trauma,less stif ness,less complications with more stable vertebral column,which can rectify or prevent kyphosis ef ectively.%目的探讨经伤椎椎弓根螺钉内固定治疗胸腰椎骨折的可行性、适应症及临床疗效。方法自2012年3月~2014年3月采用后路经伤椎植骨内固定治疗胸腰椎骨折30例,分别于术后3~5d、12个月、末次随访时复查X线片及CT,对伤椎Cobb角、椎体压缩百分比、椎管占位、内固定物状况进行随访;通过Frankel标准对脊髓神经功能进行评定。

  8. 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

  9. The clinical research of posterior transpedicular screw fixation combined with intervertebral bone grafting fusion in the treatment of Ⅱ degree and Ⅲ degree lumbar spondylolisthesis%后路椎弓根螺钉内固定联合椎间植骨融合治疗Ⅱ、Ⅲ度腰椎滑脱的临床研究

    Institute of Scientific and Technical Information of China (English)

    宁凯; 车立新; 王志刚; 李坤; 吉喆

    2012-01-01

    目的 探讨后路椎弓根螺钉内固定联合椎间植骨融合治疗Ⅱ、Ⅲ度腰椎滑脱临床疗效.方法 回顾性分析我院2009年1月~2011年1月收治入院的30例腰椎滑脱症患者临床资料,所有病例均为Ⅱ、Ⅲ度腰椎滑脱.患者均采用后路椎弓根螺钉内固定联合椎间植骨融合治疗,观察手术前后临床症状及滑脱恢复情况、术后复位、疗效评价、材料生物相容性、术后椎间隙高度及BFS评分.结果 30例患者术前均为Ⅱ、Ⅲ度腰椎滑脱,其中,19例行椎管、神经根管减压、复位固定、植骨融合治疗,11例只行复位固定、植骨融合治疗.获得随访30例,均超过12个月.30例椎间植骨全部融合,融合率为100%.BFS评分优良率达90.0%.结论 后路椎弓根螺钉内固定联合椎间植骨融合治疗Ⅱ、Ⅲ度腰椎滑脱,操作简便、固定可靠,是临床治疗中的一种值得推广的方法.%Objective To explore the curative effect of posterior transpedicular screw fixation combined with intervertebral bone grafting fusion in the treatment of Ⅱ degree and Ⅲ degree lumbar spondylolisthesis. Methods The clinical data of 30 patients with lumbar spondylolisthesis from January 2009 to January 2011 in our hospital were analyzed retrospectively. All cases were suffered with Ⅱ degree or Ⅲ degree lumbar spondylolisthesis. All patients were adopted posterior transpedicular screw fixation combined with intervertebral bone grafting fusion treatment. The clinical symptoms, slippage recovery condition before and after operation, postoperative restoration, therapeutic effect evaluation, material biocompatibility, postoperative intervertebral height and BFS score were observed. Results 30 patients all suffered with Ⅱ degree or Ⅲ degree lumbar spondylolisthesis before surgery, among whom 19 cases were treated with canalis vertebralis and nerve root canal decompression, reduction and fixation and bone graft fusion. Other 11 cases were

  10. Treatment of the thoracolumbar spine fracture with posterior monosegment pedicle fixation and transpedicular impacted bone graft at injured level%单节段椎弓根固定椎体内打压植骨治疗胸腰椎压缩骨折

    Institute of Scientific and Technical Information of China (English)

    邢飞; 樊道斌; 陈宏赋; 张林胜; 朱敏

    2012-01-01

    Objective To explore the clinical effects of posterior monosegmental pedicle screw fixation in selective treatment of thoracolumbar vertebral fractures. Methods 15 patients with thoracolumbar fractures were treated with posterior monosegmental pedicle screw fixation and transpedicle impacted bone graft. The Cobb's angle and reduction of injured vertebral body height were observed. Results All cases were followed up for 6 ~ 18months. Clinical evaluation revealed that 11 cases had no pain, 4 cases with occasional pain but required no medication and all patients had a high level of satisfaction with the final results. Radiographic evaluation revealed reduction rate of the injured vertebral height was 95%. The Cobb's angle was restored from 14° ~25° to 3° ~8°. There was no implant breakage, and no signs of pseudoarthrosis were observed. Conclusions Posterior monosegmental fixation might be an adequate and effective procedure to be used in specific types of thoracolumbar spine fractures. Transpedicular impacted grafting after bone loss calculation combined with pedicle fixation has better biomechanical properties.%目的 探讨单节段椎弓根固定结合伤椎打压植骨治疗胸腰椎屈曲压缩骨折的疗效.方法 对15例胸腰椎压缩性骨折(Denis B型)患者行后路单节段经伤椎复位固定、经椎弓根伤椎打压植骨手术.测量术前术后Cobb角,计算伤椎高度恢复率,进行ODI评分,分析疗效.结果 15例患者均获随访,时间6~18个月.伤椎高度矫正率约95%,Cobb角由术前的14°~25°改善为术后的3°~8°.未出现内固定断裂、神经损伤等并发症.结论 单节段椎弓根固定椎体内植骨治疗胸腰椎压缩性骨折手术创伤小,仅固定1个运动节段;椎体内打压植骨有效解决椎体复位后产生的椎体内骨缺损.

  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. 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.

  13. Analysis of Spinal Fixation System and Intervertebral Bone Grafting Treating Lumbar Spondylolisthesis in 30 Cases%脊椎钉棒固定系统并椎体间植骨治疗腰椎滑脱症30例分析

    Institute of Scientific and Technical Information of China (English)

    梁世勋

    2013-01-01

      目的:探讨脊椎钉棒固定系统并椎体间植骨治疗腰椎滑脱症的临床疗效。方法:对30例腰椎滑脱症患者采用后路椎弓根螺钉将滑脱椎体复位、提位,减轻椎管压力,并接受椎间植骨融合治疗。结果:30例患者接受手术治疗后麻木明显得到改善,腰腿疼痛症状消失,没有一例出现感染、植骨块移位、神经根损伤等严重并发症;完全复位率达96.67%。结论:椎弓根螺钉脊柱钉棒固定系统并结合减压植骨术是治疗椎体滑脱复位的一种有效方法,疗效确切,能够很好地维持椎间高度并且植骨融合率高,有利于患者的尽早康复。%Objective:To investigate the clinical efficacy of spinal fixation system and intervertebral bone grafting treating lumbar spondylolisthesis. Methods:30 cases of patients with lumbar spondylolisthesis were treated with posterior pedicle screw to reset the spondylolisthesis, lift and reduce pressure of canalis vertebralis, and they were accepted intervertebral bone grafting. Results:Anaesthesia was significantly improved, and symptoms of low back pain disappeared after the therapy of 30 patients receiving the operation, without serious complications of infection, bone grafting dis-placement, nerve root injury and so on;the complete reset rate was 96.67%. Conclusion:Spinal fixation system with pedicle screw combined with de-compression and bone grafting is an effective method for treating reduction of spondylolisthesis, the curative effects of which are exact, it can well maintain the height of intervertebral, and its fusion rate of bone grafting is high, in favour of patients’early rehabilitation.

  14. Computer navigated percutaneous screw fixation for traumatic pubic symphysis diastasis of unstable pelvic ring injuries

    Institute of Scientific and Technical Information of China (English)

    MU Wei-dong; WANG Hong; ZHOU Dong-sheng; YU Ling-zhi; JIA Tang-hong; LI Lian-xin

    2009-01-01

    Displaced and unstable pelvic ring injuries have been treated mainly by open reduction and internal fixation. The goal of treatment relies on restoration of pelvic anatomy with stable internal fixation, allowing early mobilization of the patient.1,2 The symphysis pubis dislocation (>25 mm) is consistent indication for anterior internal fixation.3 In most situations, the fixation of the displaced symphysis pubis requires extensive exposure, which may lead to complications including blood loss, neural or vascular injury, postoperative infections, wound healing problems and heterotopic bone formation.

  15. A feasibility investigation for modeling and optimization of temperature in bone drilling using fuzzy logic and Taguchi optimization methodology.

    Science.gov (United States)

    Pandey, Rupesh Kumar; Panda, Sudhansu Sekhar

    2014-11-01

    Drilling of bone is a common procedure in orthopedic surgery to produce hole for screw insertion to fixate the fracture devices and implants. The increase in temperature during such a procedure increases the chances of thermal invasion of bone which can cause thermal osteonecrosis resulting in the increase of healing time or reduction in the stability and strength of the fixation. Therefore, drilling of bone with minimum temperature is a major challenge for orthopedic fracture treatment. This investigation discusses the use of fuzzy logic and Taguchi methodology for predicting and minimizing the temperature produced during bone drilling. The drilling experiments have been conducted on bovine bone using Taguchi's L25 experimental design. A fuzzy model is developed for predicting the temperature during orthopedic drilling as a function of the drilling process parameters (point angle, helix angle, feed rate and cutting speed). Optimum bone drilling process parameters for minimizing the temperature are determined using Taguchi method. The effect of individual cutting parameters on the temperature produced is evaluated using analysis of variance. The fuzzy model using triangular and trapezoidal membership predicts the temperature within a maximum error of ±7%. Taguchi analysis of the obtained results determined the optimal drilling conditions for minimizing the temperature as A3B5C1.The developed system will simplify the tedious task of modeling and determination of the optimal process parameters to minimize the bone drilling temperature. It will reduce the risk of thermal osteonecrosis and can be very effective for the online condition monitoring of the process.

  16. Umbilical cord Wharton's jelly repeated culture system: a new device and method for obtaining abundant mesenchymal stem cells for bone tissue engineering.

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    Zhengqi Chang

    Full Text Available To date, various types of cells for seeding regenerative scaffolds have been used for bone tissue engineering. Among seed cells, the mesenchymal stem cells derived from human umbilical cord Wharton's jelly (hUCMSCs represent a promising candidate and hold potential for bone tissue engineering due to the the lack of ethical controversies, accessibility, sourced by non-invasive procedures for donors, a reduced risk of contamination, osteogenic differentiation capacities, and higher immunomodulatory capacity. However, the current culture methods are somewhat complicated and inefficient and often fail to make the best use of the umbilical cord (UC tissues. Moreover, these culture processes cannot be performed on a large scale and under strict quality control. As a result, only a small quantity of cells can be harvested using the current culture methods. To solve these problems, we designed and evaluated an UC Wharton's jelly repeated culture device. Using this device, hUCMSCs were obtained from the repeated cultures and their quantities and biological characteristics were compared. We found that using our culture device, which retained all tissue blocks on the bottom of the dish, the total number of obtained cells increased 15-20 times, and the time required for the primary passage was reduced. Moreover, cells harvested from the repeated cultures exhibited no significant difference in their immunophenotype, potential for multilineage differentiation, or proliferative, osteoinductive capacities, and final osteogenesis. The application of the repeated culture frame (RCF not only made full use of the Wharton's jelly but also simplified and specified the culture process, and thus, the culture efficiency was significantly improved. In summary, abundant hUCMSCs of dependable quality can be acquired using the RCF.

  17. 后路固定椎间碎骨植骨与髂骨块植骨融合术治疗退行性腰椎不稳的临床研究%Clinical study of posterior internal fixation and iliac crest or granular bone grafting lumbar interbody fusion for the treatment of the degenerative lumbar instability

    Institute of Scientific and Technical Information of China (English)

    林斌; 林秋燕; 邵泽豹

    2012-01-01

    [Objective] To compare the clinical outcome of posterior pedicle screw fixation and iliac crest or granular bone grafting lumbar interbody fusion for the treatment of degenerative lumbar instability. [ Methods] There were 75 patients with degenerative lumbar disease. They were 41 males and 34 females, aged from 27 to 68 years with an average of 55. 6 years. Clinical manifestation; there were 72 cases with lower back pain and 47 cases with intermittent claudication. All of 75 cases had leg pain, including 37 cases of unilateral kg pain, 23 cases of bilateral leg pain and 15 cases of alternative leg pair.. Fifty - seven cases were positive with straight leg raising test, 66 cases had sensory disturbance, 58 cases had movement disorders, and 45 cases had abnormal achilles tendon reflex and knee jerk reflex, and 45 cases had injuries of cauda equina. There were 32 cases with degeneration of L4、5 , 26 cases with degeneration of L5S1 , 6 cases with degeneration of L3、4, and 11 cases with degeneration more than 2 segments. They were divided into two groups randomly: iliac bone group and granular bone group. The iliac bone group were treated with decompression, internal fixation for degenerative lumbar instability with pedicle screw and interbody fusion with iliac crest grafting. The granular bone group were treated with decompression, internal fixation and with granular bone grafting fusion. All of the cases had X -ray in routine and oblique view, CT and MRI preoperatively. The Japanese Orthopedic Association (JOA) score, Oswestry Disability Index (ODI) were evaluated before and 3, 6, 12 months after surgery. And fusion situation was evaluated by reviewing the roentgenographic film. [ Results] ( I ) Significant difference of JOA score and 0D1 were founded in each group before and after surgery. But it was no significant different between two groups. (2) The loss of intervertebral height was significant different between two group before and after surgery. The loss of

  18. 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...

  19. 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.

  20. Operative Cost Comparison: Plating Versus Intramedullary Fixation for Clavicle Fractures.

    Science.gov (United States)

    Hanselman, Andrew E; Murphy, Timothy R; Bal, George K; McDonough, E Barry

    2016-09-01

    Although clavicle fractures often heal well with nonoperative management, current literature has shown improved outcomes with operative intervention for specific fracture patterns in specific patient types. The 2 most common methods of midshaft clavicle fracture fixation are intramedullary and plate devices. Through retrospective analysis, this study performed a direct cost comparison of these 2 types of fixation at a single institution over a 5-year period. Outcome measures included operative costs for initial surgery and any hardware removal surgeries. This study reviewed 154 patients (157 fractures), and of these, 99 had intramedullary fixation and 58 had plate fixation. A total of 80% (79 of 99) of intramedullary devices and 3% (2 of 58) of plates were removed. Average cost for initial intramedullary placement was $2955 (US dollars) less than that for initial plate placement (Pcost for removal was $1874 less than that for plate removal surgery (P=.2). Average total cost for all intramedullary surgeries was $1392 less than the average cost for all plating surgeries (Pcost for all intramedullary surgeries requiring plate placement and removal was $653 less than the average cost for all plating surgeries that involved only placement (P=.04). Intramedullary fixation of clavicle fractures resulted in a statistically significant cost reduction compared with plate fixation, despite the incidence of more frequent removal surgeries. [Orthopedics.2016; 39(5):e877-e882.].

  1. Southwick Osteotomy Stabilised with External Fixator

    Science.gov (United States)

    Grubor, Predrag; Mitkovic, Milorad; Grubor, Milan

    2014-01-01

    ABSTRACT Introduction: Epiphysiolysis of the femoral head is the most common accident occurring towards the end of pre-puberty and puberty growth. Case report: The author describes the experience in the treatment of chronic epiphysiolysis in two patients treated by Southwick osteotomy. The site is accessed by way of a 15-cm long lateral skin incision and the trochanteric region is reached through the layers. The osteotomy angles prepared beforehand on a thin aluminium model are used to mark the Southwick osteotomy site on the anterior and lateral sides at the level of the lesser trochanter. Before performing the trochanteric osteotomy, two Mitković convergent pins type M20 are applied distally and proximally, above the planned osteotomy site. A tenotomy of the iliopsas muscle is performed, and then the previously marked bone triangle is redissected up to three quarters of the width of the femur. The distal part of the femur is rotated inwards, so that the patella is turned towards the ceiling. The osteotomised fragments of the femur are adapted, repositioned and fixated by installing an external fixator on the previously placed pins. Two more pins are placed, one proximally and one distally, with a view to adequately stabilising the femur. The patient was mobile from day two after the surgery. If, after the surgery, the lead surgeon realises that there is a requirement to make a correction of 5, 10 and 15 degrees of the valgus, varus, anteversion or retroversion deformity, the correction shall be performed without surgically opening the patient, using the fixator pins. Conclusion: After performing a Southwick osteotomy it is easier to adapt, reposition and fixate the osteotomised fragments of the femur using a fixator type M20. Adequate stability allows regaining mobility quickly, which in turn is the best prevention of chondrolysis of the hip. It is possible to make post-operative valgus, varus, anteversion and retroversion corrections of 5, 10 and 15 degrees

  2. The value of calcaneal bone mass measurement using a dual X-ray laser calscan device in risk screening for osteoporosis

    Directory of Open Access Journals (Sweden)

    Gulseren Kayalar

    2009-01-01

    Full Text Available OBJECTIVE: To evaluate how bone mineral density in the calcaneus measured by a dual energy X-ray laser (DXL correlates with bone mineral density in the spine and hip in Turkish women over 40 years of age and to determine whether calcaneal dual energy X-ray laser variables are associated with clinical risk factors to the same extent as axial bone mineral density measurements obtained using dual energy x-ray absorbtiometry (DXA. MATERIALS AND METHODS: A total of 2,884 Turkish women, aged 40-90 years, living in Ankara were randomly selected. Calcaneal bone mineral density was evaluated using a dual energy X-ray laser Calscan device. Subjects exhibiting a calcaneal dual energy X-ray laser T- score <-2.5 received a referral for DXA of the spine and hip. Besides dual energy X-ray laser measurements, all subjects were questioned about their medical history and the most relevant risk factors for osteoporosis. RESULTS: Using a T-score threshold of -2.5, which is recommended by the World Health Organization (WHO, dual energy X-ray laser calcaneal measurements showed that 13% of the subjects had osteoporosis, while another 56% had osteopenia. The mean calcaneal dual energy X-ray laser T-score of postmenopausal subjects who were smokers with a positive history of fracture, hormone replacement therapy (HRT, covered dressing style, lower educational level, no regular exercise habits, and low tea consumption was significantly lower than that obtained for the other group (p<0.05. A significant correlation was observed between the calcaneal dual energy X-ray laser T-score and age (r=-0.465, p=0.001, body mass index (BMI (r=0.223, p=0.001, number of live births (r=-0.229, p=0.001, breast feeding time (r=-0.064, p=0.001, and age at menarche (r=-0.050, p=0.008. The correlations between calcaneal DXL and DXA T-scores (r=0.340, p=0.001 and calcaneal DXL and DXA Z-scores (r=0.360, p=0.001 at the spine, and calcaneal DXL and DXA T- scores (r=0.28, p=0.001 and calcaneal

  3. Subtrochanteric femur fracture treated by intramedullary fixation

    Institute of Scientific and Technical Information of China (English)

    Zu-Bin Zhou; Song Chen; You-Shui Gao; Yu-Qiang Sun; Chang-Qing Zhang; Yao Jiang

    2015-01-01

    Purpose: To discuss surgical technique, operative efficacy and clinical outcome of intramedullary fixation in the treatment of subtrochanteric femur fractures.Methods: From February 2011 to February 2013, 76 cases of subtrochanteric femur fractures were treated by intramedullary fixation in our hospital, including 53 males and 23 females, with the age range of 37 -72 years (mean 53.5 years).According to Seinsheimer classification, there were 2 cases of type Ⅰ, 7 type Ⅱ,15 type Ⅲ, 23 type Ⅳ and 29 type Ⅴ.Firstly, all patients underwent closed reduction with the guidance of C-arm fluoroscopy in a traction table.Two cases of type Ⅰ and 3 cases of type Ⅲ fractures had ideal closed reduction followed by internal fixation.The others needed additional limited open reduction.Radiographic examination was used to evaluate callus formation and fracture healing in postoperative 1, 3, 6 and 12 months follow-up.Functional recovery was evaluated by Harris Hip Scoring (HHS) system.Results: Patients were followed up for 6-12 months.All fractures were healed except one patient with delayed union.The average bone union time was 4.5 months.According to HHS system, 65 cases were considered as excellent in functional recovery, 8 good, 2 fair and 1 poor.The proportion of the patients with excellent and good recovery was 96.05%.Conclusion: Intramedullary fixation is feasible for the treatment of subtrochanteric femur fracture.The accuracy of intraoperative reduction and surgical skill are important for the clinical outcome and the patients' prognosis.

  4. Biomechanical Study of Acetabular Tridimensional Memoryalloy Fixation System

    Science.gov (United States)

    Liu, Xin-Wei; Xu, Shuo-Gui; Zhang, Yun-Tong; Zhang, Chun-Cai

    2011-07-01

    We developed the acetabular tridimensional memoryalloy fixation system (ATMFS), which is made of NiTi shape memory alloy, according to the specific mechanical properties of biological memory material, NiTi shape memory alloy and measured distribution of contact area and pressure between the acetabulum and the femoral head of cadaveric pelvis. Seven formalin-preserved cadaveric pelves were used for this investigation. Pressure-sensitive film was used to measure contact area and pressure within the anterior, superior, and posterior regions of the acetabulum. The pelves were loaded under the following four conditions: (1) intact; (2) following a creation posterior wall fracture defect; (3) following reduction and standard internal fixation with reconstruction plate; and (4) following reduction and internal fixation with a new shape memory alloy device named ATMFS. A posterior wall fracture was created along an arc of 40° to 90° about the acetabulur rim. Creation of a posterior wall defect resulted in increased load in the superior acetabulum (1485 N) as compared to the intact condition (748 N, P = 0.009). Following reduction and internal fixation, the load distributed to the superior acetabulum (1545 N) was not statistically different from the defect condition. Following the fixation with ATMFS, the load seen at the superior region of the actabulum (964 N) was familiar with fixation with reconstruction plate and was not different from intact state ( P = 0.45). These data indicate that the use of ATMFS as a fracture internal fixation device resulted a partial restoration of joint loading parameters toward the intact state. ATMFS fixation may result in a clinical benefit.

  5. Combined application of vascularized pedicled pectoralis major clavicular periosteal flap and locking plate fixation plus bone morphogenetic protein implantation in the treatment of clavicular defect and nonunion after operation%带血管胸大肌蒂锁骨膜联合锁定钛板固定BMP植入治疗锁骨术后骨不愈合及骨缺损

    Institute of Scientific and Technical Information of China (English)

    孙强; 郑加法

    2009-01-01

    目的 探讨锁骨骨折术后骨缺损、骨折不愈合的临床特点,评价锁定钛板固定骨形态发生蛋白(bone morphogenetic protein,BMP)植入联合带血管胸大肌蒂锁骨膜转位的治疗效果.方法 2004年1月-2008年4月,锁骨骨折不愈合12例,平均年龄42.8岁,均行内固定物取出,清除骨折端纤维瘢痕及硬化骨,锁定钛板同定BMP植入,带血管胸大肌蒂锁骨膜转位覆盖,术后进行功能康复锻炼. 结果 12例患者术后均获得随访,时间8~24个月,平均1.2年,应用Constant-Murley肩关节评分系统进行评价,所有患者均在4~7个月达到临床愈合,部分患者已将内固定物取出. 结论 锁定钛板固定BMP植入联合带血管胸大肌蒂锁骨膜转位治疗锁骨骨缺损、骨不连,可取得良好的临床效果.%Objective To investigate the clinical characteristics of clavicular defect and nonunion after operation and evaluate the clinical effects of vascularized pedicled pectoralis major clavicular periosteal flap and locking plate fixation plus bone morphogenetic protein (BMP) implantation. Methods From January 2004 to April 2008, 12 patients (mean age, 42.8 years old) with clavicular defect and nonunion were treated in Zhongshan Hospital. The internal fixators were removed, and then fibrous scars and sclerotic bones were cleared. The clavicular detects were fixed with locking plate, with implantation of the BMP. The wound was covered with vascularized pedicled pectoralis major clavicular periosteal flap. Postoperative functional rehabilitation exercises were performed. Results All patients were followed up for 8-24 months (mean 1.2 years). The clinical results were evaluated by Constant-Murley scoring system. The clavicular defects were healed in all patients within 4-7 months, and the internal fixators were successfully removed from some of the patients. Conclusions Vascularized pedicled pectoralis major clavicular periosteal flap combined with locking plate fixation

  6. 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

  7. Surgery Locking Compression Plate Fixation for the Treatment of Long Bone Comminuted Fracture of the Limbs%锁定加压钢板内固定手术对四肢长骨粉碎性骨折的治疗价值

    Institute of Scientific and Technical Information of China (English)

    封小东

    2016-01-01

    Objective Application in patients with limb long bone comminuted fracture internal fixation with locking compression plate (LCP) analysis, this paper discusses the clinical effect of surgical treatment. Methods In our hospital in 2014-2015 were a total of 60 patients with limbs long bone comminuted fracture as a clinical research data, the patients were randomly divided into two groups: treatment group and control group, 30 cases of patients in each group. The control group used the traditional plaster external fixation + manual reduction treatment, treatment group application of LCP internal fixation surgery reset, compare two methods of surgical treatment effect. Results After treatment, the treatment group was significantly higher than the control group, after statistics, a significant statistical significance (P<0.05). Follow-up survey was performed after the surgery, two groups of anatomical repositioning effect is good, none of the patients with complications. Treatment group patients average healing time was significantly shorter than the control group the average healing time of, the statistics, a significant statistical significance (P<0.05). Conclusion Limbs long bone comminuted fracture surgery treatment, application of locking compression plate fixation can achieve significant treatment effect, worthy of popularization and application in clinic.%目的:对四肢长骨粉碎性骨折患者应用锁定加压钢板(LCP)内固定手术治疗的临床效果进行分析探讨。方法将本院在2014-2015年收治的四肢长骨粉碎性骨折患者共计60例作为临床研究资料,将患者随机分为两组:治疗组与对照组,每组患者有30例。对照组应用传统的石膏外固定+手法复位治疗,治疗组应用 LCP 内固定手术复位,比较两种手术方法的治疗效果。结果经过治疗后,治疗组的优良率显著高于对照组,经统计,有显著的统计学意义(P<0.05)。手术后对患者进行

  8. COMBINATION OF FIXATION TECHNIQUES IN THE MANAGEMENT OF COMPLEX DISTAL RADIUS FRACTURE- OUR EXPERIENCES

    Directory of Open Access Journals (Sweden)

    Isaac Sunder Sen

    2016-10-01

    Full Text Available BACKGROUND The aim of the study is to categorically suggest the apt method of surgical technique for a particular type of distal radius fracture (Frykman’s type III-VI. Distal radius fracture are among the most common fractures of the upper extremity inspite of increased focus on regular prevention of osteoporosis, early identification and its prompt management. Most distal radius fractures are the result of low energy mechanisms that can be successfully treated either nonoperatively or with a variety of operative techniques if indicated. Complex distal radius fractures occur most commonly in high-energy injuries with extensive comminution or bone loss and associated soft tissue or vascular injuries. These high-energy fractures can present challenges in reconstructing the distal radius. Effective restoration of the bony architecture requires a thorough knowledge of distal radius anatomy, understanding of the goals of treatment, versatility in surgical approaches and familiarity with multiple fixation options. Although, majority of the extra-articular fracture without signs of instability can be successfully managed with POP immobilisation for a period of 4-5 weeks followed by active physiotherapy, other types (Frykman’s III-VI need surgical management that too with combination of surgical techniques namely augmented spanning external fixator with supplemented K-wire fixation or external fixation followed by fragment specific volar locking compression plate osteosynthesis. MATERIALS AND METHODS I have studied 50 cases of distal radius fractures classified using Frykman’s classification using combination of techniques namely augmented spanning external fixator application with K-wire supplementation and spanning external fixator application followed by volar LCP fixation in which external fixator had been used as a reduction tool in majority of the cases and external fixator had been removed after plate osteosynthesis. In some cases retained

  9. Late vertebral body fracture after lumbar transpedicular fixation. Report of three cases.

    Science.gov (United States)

    Missori, Paolo; Ramieri, Alessandro; Costanzo, Giuseppe; Peschillo, Simone; Paolini, Sergio; Miscusi, Massimo; D'Andrea, Giancarlo; Delfini, Roberto

    2005-07-01

    Late-onset vertebral body (VB) fracture after lumbar transpedicular fixation has not been previously described in the literature. The authors present three cases in which VB fracture occurred several months after posterolateral fixation in patients with degenerative disease or traumatic injury. The authors suggest that postoperative osteopenia, modified load-sharing function, and intravertebral clefts were responsible for the fractures. Two women and one man were evaluated at a mean follow-up interval of 3 months. Two patients suffered recurrent lumbar pain. Radiography and magnetic resonance imaging revealed fracture of some of the instrumentation-treated VBs. These two patients underwent surgical superior or inferior extension of instrumentation. The third, an asymptomatic patient, received conservative management. The two patients who underwent reoperation made complete recoveries, and there was no evidence of further bone collapse in any case. The authors speculate that alterations in the VBs may occur following application of spinal instrumentation. In rare cases, the device can fracture and consequently lead to recurrent lumbar back pain. Recovery can be achieved by extending the instrumentation in the appropriate direction.

  10. Evaluation of Qualitative Changes in Simulated Periodontal Ligament and Alveolar Bone Using a Noncontact Electromagnetic Vibration Device with a Laser Displacement Sensor.

    Science.gov (United States)

    Kobayashi, Hiroshi; Hayashi, Makoto; Yamaoka, Masaru; Yasukawa, Takuya; Ibi, Haruna; Ogiso, Bunnai

    2016-01-01

    Evaluating periodontal tissue condition is an important diagnostic parameter in periodontal disease. Noncontact electromagnetic vibration device (NEVD) was previously developed to monitor this condition using mechanical parameters. However, this system requires accelerometer on the target tooth. This study assessed application of laser displacement sensor (LDS) to NEVD without accelerometer using experimental tooth models. Tooth models consisted of cylindrical rod, a tissue conditioner, and polyurethane or polyurethane foam to simulate tooth, periodontal ligament, and alveolar bone, respectively. Tissue conditioner was prepared by mixing various volumes of liquid with powder. Mechanical parameters (resonant frequency, elastic modulus, and coefficient of viscosity) were assessed using NEVD with the following methods: Group A, measurement with accelerometer; Group B, measurement with LDS in the presence of accelerometer; and Group C, measurement with LDS in the absence of accelerometer. Mechanical parameters significantly decreased with increasing liquid volume. Significant differences were also observed between the polyurethane and polyurethane foam models. Meanwhile, no statistically significant differences were observed between Groups A and B; however, most mechanical parameters in Group C were significantly larger and more distinguishable than those of Groups A and B. LDS could measure mechanical parameters more accurately and clearly distinguished the different periodontal ligament and alveolar bone conditions.

  11. Comparative study of bone repair in mandibular body osteotomy between metallic and absorbable 2.0 mm internal fixation systems. Histological and histometric analysis in dogs: a pilot study.

    Science.gov (United States)

    Sverzut, C E; Kato, R B; Rosa, A L; Trivellato, A E; Sverzut, A T; da Silveira, K M; de Oliveira, P T

    2012-11-01

    The objective of this study was to compare the bone repair along a mandibular body osteotomy stabilized with 2.0 mm absorbable and metallic systems. 12 male, adult mongrel dogs were divided into two groups (metallic and absorbable) and subjected to unilateral osteotomy between the mandibular third and fourth premolars, which was stabilized by applying two 4-hole plates. At 2 and 18 weeks, three dogs from each group were killed and the osteotomy sites were removed and divided equally into three parts: the upper part was labelled the tension third (TT), the lower part the compression third (CT), and the part between the TT and CT the intermediary third (IT). Regardless of the treatment system, union between the fragments was observed at 18 weeks and the CT showed more advanced stages of bone repair than the TT. Histometric analysis did not reveal any significant differences among the 3 parts or systems in the distance between bone fragments at 2 weeks. Although at 18 weeks the proportions of newly formed bone did not differ among TT, IT and CT, significantly enhanced bone formation was observed in all sections for the metallic group. The patterns of repair were distinct between treatments.

  12. In vivo implant fixation of carbon fiber-reinforced PEEK hip prostheses in an ovine model.

    Science.gov (United States)

    Nakahara, Ichiro; Takao, Masaki; Bandoh, Shunichi; Bertollo, Nicky; Walsh, William R; Sugano, Nobuhiko

    2013-03-01

    Carbon fiber-reinforced polyetheretherketone (CFR/PEEK) is theoretically suitable as a material for use in hip prostheses, offering excellent biocompatibility, mechanical properties, and the absence of metal ions. To evaluate in vivo fixation methods of CFR/PEEK hip prostheses in bone, we examined radiographic and histological results for cementless or cemented CFR/PEEK hip prostheses in an ovine model with implantation up to 52 weeks. CFR/PEEK cups and stems with rough-textured surfaces plus hydroxyapatite (HA) coatings for cementless fixation and CFR/PEEK cups and stems without HA coating for cement fixation were manufactured based on ovine computed tomography (CT) data. Unilateral total hip arthroplasty was performed using cementless or cemented CFR/PEEK hip prostheses. Five cementless cups and stems and six cemented cups and stems were evaluated. On the femoral side, all cementless stems demonstrated bony ongrowth fixation and all cemented stems demonstrated stable fixation without any gaps at both the bone-cement and cement-stem interfaces. All cementless cases and four of the six cemented cases showed minimal stress shielding. On the acetabular side, two of the five cementless cups demonstrated bony ongrowth fixation. Our results suggest that both cementless and cemented CFR/PEEK stems work well for fixation. Cup fixation may be difficult for both cementless and cemented types in this ovine model, but bone ongrowth fixation on the cup was first seen in two cementless cases. Cementless fixation can be achieved using HA-coated CFR/PEEK implants, even under load-bearing conditions.

  13. Treatment of multiple base unstable fractures of metatarsal bone combined with tarsometatarsal joint injury by open reduction and internal fixation%切开复位内固定治疗多发跖骨基底部不稳定骨折合并跖跗关节损伤

    Institute of Scientific and Technical Information of China (English)

    张海波; 李勇; 蔡友芳

    2013-01-01

    [Objective] To explore the therapy and the clinical effectiveness of open reduction and internal fixation in the treatment of multiple base unstable fractures of metatarsal bone combined with tarsometatarsal joint injury. [ Method] From January 2003 to July 2001,35 patients with multiple base unstable fractures of metatarsal bone combined with tarsometatarsal joint injuries underwent open reduction and internal fixation. There were 22 males and 13 females with an average age of 37.4 years (range,20 -58 years) ,with total of 89 base fractures. There were 9 cases in the second to third metatarsal bone,7 in the third to fourth metatarsal bone and 19 in the second to fourth metatarsal bone. The classification of tarsometatarsal joint injury showed that there were 2 case of simple middle column ,7 cases of inner and middle columns, 10 cases of lateral and middle colums ,16 cases of three columns. The second and third base fractures of metatarsal bone were treated with transarticular fixation by miniplate. [Result]All the patients were followed up,the duration ranged from 12 to 30 months (averaged 22. 5 months). No complications such as wound infection, skin necrosis and fixture breakage were found postoperatively. The clinical fracture healing time was 8 to 17 weeks (mean ,13.9 weeks). The results were excellent in 11 cases, good in 18 cases, fair in 4 cases, and poor in 2 cases according to American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score system,with excellent and good result rate of 82. 9%. [ Conclusion ] The anatomical reduction and stable fixation of tarsometatarsal joint and metatarsal base are also important to rebuild the function of foot, can reduce incidence rate of osteoarthritis at midfoot and obtain very good clinical effect. Reasonable internal fixation should be selected according to injury type.%[目的]探讨切开复位内固定治疗多发跖骨基底部不稳定骨折合并跖跗关节损伤的方法及临床疗效.[方法]2003年1

  14. Mechanical evaluation of external skeletal fixator-intramedullary pin tie-in configurations applied to cadaveral humeri from red-tailed hawks (Buteo jamaicensis).

    Science.gov (United States)

    Van Wettere, Arnaud J; Redig, Patrick T; Wallace, Larry J; Bourgeault, Craig A; Bechtold, Joan E

    2009-12-01

    Use of external skeletal fixator-intramedullary pin (ESF-IM) tie-in fixators is an adjustable and effective method of fracture fixation in birds. The objective of this study was to determine the contribution of each of the following parameters to the compressive and torsional rigidity of an ESF-IM pin tie-in applied to avian bones with an osteotomy gap: (1) varying the fixation pin position in the proximal bone segment and (2) increasing the number of fixation pins in one or both bone segments. ESF-IM pin tie-in constructs were applied to humeri harvested from red-tailed hawks (Buteo jamaicensis) (n=24) that had been euthanatized for clinical reasons. Constructs with a variation in the placement of the proximal fixation pin and with 2, 3, or 4 fixation pins applied to avian bone with an osteotomy gap were loaded to a defined displacement in torque and axial compression. Response variables were determined from resulting load-displacement curves (construct stiffness, load at 1-mm displacement). Increasing the number of fixation pins from 1 to 2 per bone segment significantly increased the stiffness in torque (110%) and compression (60%), and the safe load in torque (107%) and compression (50%). Adding a fixation pin to the distal bone segment to form a 3-pin fixator significantly increased the stiffness (27%) and safe load (20%) in torque but not in axial compression. In the configuration with 2 fixation pins, placing the proximal pin distally in the proximal bone segment significantly increased the stiffness in torque (28%), and the safe load in torque (23%) and in axial compression (32%). Results quantified the relative importance of specific parameters affecting the rigidity of ESF-IM pin tie-in constructs as applied to unstable bone fracture models in birds.

  15. 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.

  16. Bone tumor

    Science.gov (United States)

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

  17. 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.

  18. Contralateral reversed distal femoral locking plate for fixation of subtrochanteric femoral fractures

    Institute of Scientific and Technical Information of China (English)

    Paritosh Gogna; Reetadyuti Mukhopadhyay; Amanpreet Singh; Ashish Devgan; Sahil Arora; Amit Batra; Sushil Kumar Yadav

    2015-01-01

    Purpose:Subtrochanteric fractures of the femur are being managed successfully with various intramedullary and extramedulary implants with reasonable success.However,these implants require precise placement under image intensifier guidance,which exposes the surgeon to substantial amount of radiation.It also restricts the management of these fractures at peripheral centers where facility of image intensifiers is not available.Keeping this in mind we designed this study to identify if contralateral reversed distal femoral locking plate can be used successfully without the use of image intensifier.Methods:Twenty-four consecutive patients (18 men and 6 women) with a mean age of 28 years (range 19-47 years) suffering subtrochanteric fractures of the femur underwent open reduction and internal fixation with reversed contralateral distal femoral locking plate.The outcome was assessed at the mean follow-up period of 3.2 years (range 2-4.6 years) using the Harris hip score.Results:Twenty-one fractures united with the primary procedure,with a mean time of consolidation being 11 weeks (range,9-16 weeks).One patient developed superficial suture line infection,which resolved with oral antibiotics.Another patient had a fall 3 weeks after surgery and broke the plate.Repeat surgery with reversed distal femoral locking compression plate was performed along with bone grafting and the fracture united.Two cases had nonunion,which went in for union after bone grafting.The mean Harris hip score at the time of final follow-up was 90.63 (range 82-97).Conclusion:The reversed contralateral distal femoral plate is a biomechanically sound implant,which when used for fixation of the subtrochanteric fractures with minimal soft tissue stripping shows results comparable to those achieved by using other extramedullary implants as well as intramedullary devices.The added advantage of this implant is its usability in the absence of an image intensifier.

  19. 微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折%Open reduction and miniplate fixation with autogenous cancellous bone graft for comminuted talar neck fractures

    Institute of Scientific and Technical Information of China (English)

    魏世隽; 蔡贤华; 刘曦明; 陈家; 张志文; 汪波

    2013-01-01

    目的 探讨切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折的手术方法及疗效.方法 2010年1月~2012年1月,对我院收治的15例闭合性距骨颈粉碎性骨折患者,根据Hawkins分型:Ⅱ型11例,Ⅲ型4例.术前常规行CT三维重建明确骨折类型和粉碎程度,择期行切开复位微型接骨板内固定加自体松质骨移植术.术后定期复查X片及CT观察骨折愈合情况,并记录相关并发症,采用Hawkins评分标准评估疗效.结果 本组14例获得随访,随访时间12~24m,,平均16.4m.术后外侧切口边缘部分坏死1例,经局部清创换药后治愈,无并发感染,骨折均在8~12w内获得愈合,平均愈合时间11.3w,无畸形愈合发生,距骨体部分坏死1例(Ⅲ型),轻度创伤性关节炎3例(Ⅱ型1例,Ⅲ型2例),末次随访时未发现内固定松动断裂.Hawkins 评分:优7例(Ⅱ型),良5例(Ⅱ型4例,Ⅲ型1例),可2例(Ⅲ型).结论 采用切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折,术中可获得满意复位,牢靠的内固定可有效维持骨折复位,自体松质骨移植可促进骨折愈合,是治疗距骨颈粉碎性骨折的有效方法.%Objective To evaluate the surgical technique and clinical outcome of open reduction and miniplate fixation with autogenous cancellous bone graft for comminuted talar neck fractures.Method 15 patients with closed comminuted talar neck fractures were included between Jan 2010 and Jan 2012.According to Hawkins classification,11 cases were type Ⅱ fractures and 4 cases type Ⅲ fractures.All cases were evaluated carefully with X-ray and CT scan preoperatively to define the type and displacement of fractures.Open reduction and miniplate fixation with autogenous cancellous bone graft was performed until the swelling of soft tissue was vanished.The surgical wound healing was assessed after the surgery.X-ray and CT scan were taken in the follow

  20. Effect of PFNA fixation combined with salmon calcitonin in the treatment of senile femoral intertrochanteric fracture and the influence on bone mineral density%PFNA固定联合鲑鱼降钙素治疗老年股骨粗隆间骨折的效果及对骨密度的影响

    Institute of Scientific and Technical Information of China (English)

    应挺君

    2015-01-01

    目的:研究股骨近端防旋髓内钉(PFNA)内固定与鲑鱼降钙素(SCT)联合治疗老年股骨粗隆间骨折的效果及其对骨密度(BMD)的影响。方法将老年股骨粗隆间骨折患者82例随机分成SCT组与对照组,各41例。两组均行PFNA内固定术,对照组术后应用钙尔奇D600,SCT组在对照组的基础上加用SCT,比较两组的手术时间、术中出血量、术后住院时间及骨折愈合时间等手术指标,随访比较两组手术前后Harris评分、视觉模拟评分(VAS)、BMD以及髋关节功能。结果 SCT组的住院时间与骨折愈合时间明显短于对照组,VAS降低较对照组明显(P0.05)。结论 PFNA内固定治疗老年股骨粗隆间骨折具有显著效果,配合SCT治疗可提高BMD,促进骨折愈合,改善患者的生活质量。%Objective To investigate the efficacy of PFNA fixation combined with salmon calcitonin (SCT) in the treat-ment of senile femoral intertrochanteric fracture and the effects on bone mineral density (BMD). Methods 82 cases of senile femoral intertrochanteric fracture patients were randomly divided into SCT group and control group, with 41 cas-es in each group. Both groups underwent PFNA fixation, the control group received caltrate D600 treatment, SCT group received SCT on the basis of the control group, the surgical indexes such as operative time, blood loss, hospitai stay time and bone healing time of the two groups were compared, the Harris score, VAS score, BMD and hip function be-fore and after surgery of the two groups were followed and compared. Results The hospital stay time and bone healing time in SCT group was significantly shorter than the control group, and the VAS reduction was significantly better than the control group (P0.05). Conclusion PFNA fixation in the treatment of senile femoral intertrochanteric fracture has a signif-icant effect, combined with salmon calcitonin can improve BMD, promote healing and improve

  1. Treatment of anterior decompression, bone grafting and internal fixation combined with coblation neucleoplasty for patients with cervical spondylosis involved multilevel%前路减压植骨内固定联合髓核成形术治疗多节段受累颈椎病

    Institute of Scientific and Technical Information of China (English)

    张非; 李青; 张爱明; 梁道臣

    2013-01-01

    目的:探讨前路减压植骨内固定联合等离子髓核成形术治疗多节段受累颈椎病的临床效果。方法回顾性分析2012年3月至12月中山市人民医院采用前路减压植骨内固定结合等离子髓核成形术治疗的30例多节段受累颈椎病患者的临床资料,采用日本骨科学会(JOA)评分对术后临床症状改善情况进行评价。结果30例患者均获得有效随访,随访时间4~9个月(平均6.8个月)。患者术前不适症状均有不同程度改善,无神经功能加重及内固定松动、骨笼脱出等严重并发症发生。术后3个月JOA评分为(14±1)分,较术前的(10±2)分明显改善(t =8.143,P=0.000),JOA改善率为45%。结论前路减压植骨内固定结合等离子髓核成形术治疗多节段受累颈椎病近期效果稳定,并发症少。%Objective To explore clinical effect of anterior decompression, bone grafting and internal fixation combined with coblation neucleoplasty in the treatment of multilevel cervical spondylosis. Methods Clinical data of 30 patients with multilevel cervical spondylosis from March 2012 to December 2012 were retrospectively analyzed and all of them were treated by mono-segmented cervical anterior decompression, bone grafting and internal fixation combined with coblation neucleoplasty in Zhongshan People's Hospital. Clinical effects were evaluated by Japanese Orthopaedic Association (JOA) score. Results All patients obtained follow-up with the average time of 6.8 months (4-9 months). Discomfort symptoms were improved after the operation. No nerve function aggravation occurred, also, no serious complications such as internal fixation loosening or cage pull-out had happened. Compared to preoperative JOA score, JOA score at 3 months postoperatively was improved from (10 ± 2) to (14 ± 1) (t = 8.143,P = 0.000), JOA improvement rate was 45%. Conclusions Mono-segmented cervical anterior decompression, bone graft fusion

  2. 自固化磷酸钙人工骨植骨联合可塑形钛板内固定治疗 Sanders Ⅲ,Ⅳ型跟骨骨折%Autosetting Calcium Phosphate Cement Bone-Grafting and Internal Fixation with Shaping Titanium Plate for Treatment of SandersⅢ,ⅣCalcaneal Fractures

    Institute of Scientific and Technical Information of China (English)

    韩振学; 李志仙

    2014-01-01

    [ ABSTRACT] Objective To investigate the curative effect of Sanders Ⅲ,Ⅳ calcaneal fractures by autosetting calcium phosphate cement bone-grafting and internal fixation with shaping titanium plate.Methods Twenty-eight cases(28 feet) SandersⅢ,Ⅳcalcaneal frac-tures adopted open reduction with shaping titanium plate internal fixation combined with autosetting calcium phosphate cement bone-grafting, the shaping titanium plate were placed at the outward of calcaneus,reset evaluation of calcaneal fractures by measuring Bohler's Angle,Gis-sane's Angle in postoperation.Results All patients were followed up,postoperative skin necrosis in 2 cases and sural nerve injury in 1 case. After 6 months,Bohler's Angle in 20 foot≥35°,in 8 foot≥30°,Gissane Angle fully recovered to normal range and calcaneal varus deformity on axial were not seen.Fracture healing time was 2~3 months,according to Maryland foot scoring system,treatment effects of all patients were as follows:excellent in 15 feet,good in 5 feet,normal in 3 feet and poor in 2 feet,the total excellent and good rate was 83.7%,the excel-lent and good rate ofⅣtype was 56.2%.Conclusion The treatment of SandersⅢ,Ⅳcalcaneal fractures by autosetting calcium phosphate cement bone-grafting and internal fixation with shaping titanium plate is simple and its curative effect is satisfied.%目的:探讨自固化磷酸钙人工骨植骨联合可塑形钛板内固定治疗Sanders Ⅲ,Ⅳ型跟骨骨折的疗效。方法对28例(28足) SandersⅢ,Ⅳ型跟骨骨折均采用切开复位可塑形钛板固定联合自固化磷酸钙人工骨治疗,跟骨外侧放置可塑形钛板,术后测量Bohler's 角、Gissane's角,评价跟骨骨折的复位情况。结果所有患者均得到随访,术后皮缘坏死2例,腓肠神经损伤1例。术后6个月Bohler's 角20足≥35°,8足≥30°,Gissane角全部恢复至正常范围,轴位片上未见跟骨内翻畸形。骨折愈合时间2~3个月,

  3. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Polymethylmethacrylate (PMMA) bone cement. 888... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device...: Polymethylmethacrylate (PMMA) Bone Cement.”...

  4. Influence of internal fixation systems on radiation therapy for spinal tumor.

    Science.gov (United States)

    Li, Jingfeng; Yan, Lei; Wang, Jianping; Cai, Lin; Hu, Dongcai

    2015-07-08

    In this study, the influence of internal fixation systems on radiation therapy for spinal tumor was investigated in order to derive a theoretical basis for adjustment of radiation dose for patients with spinal tumor and internal fixation. Based on a common method of internal fixation after resection of spinal tumor, different models of spinal internal fixation were constructed using the lumbar vertebra of fresh domestic pigs and titanium alloy as the internal fixation system. Variations in radiation dose in the vertebral body and partial spinal cord in different types of internal fixation were studied under the same radiation condition (6 MV and 600 mGy) in different fixation models and compared with those irradiated based on the treatment planning system (TPS). Our results showed that spinal internal fixation materials have great impact on the radiation dose absorbed by spinal tumors. Under the same radiation condition, the influence of anterior internal fixation material or combined anterior and posterior approach on radiation dose at the anterior border of the vertebral body was the greatest. Regardless of the kinds of internal fixation method employed, radiation dose at the anterior border of the vertebral body was significantly different from that at other positions. Notably, the influence of posterior internal fixation material on the anterior wall of the vertebral canal was the greatest. X-ray attenuation and scattering should be taken into consideration for most patients with bone metastasis that receive fixation of metal implants. Further evaluation should then be conducted with modified TPS in order to minimize the potentially harmful effects of inappropriate radiation dose.

  5. Traumatic lumbar hernia repair: a laparoscopic technique for mesh fixation with an iliac crest suture anchor.

    Science.gov (United States)

    Links, D J R; Berney, C R

    2011-12-01

    Traumatic lumbar hernia (TLH) is a rare presentation. Traditionally, these have been repaired via an open approach. Recurrence can be a problem due to the often limited tissue available for mesh fixation at the inferior aspect of the hernia defect. We report the successful use of bone suture anchors placed in the iliac crest during transperitoneal laparoscopy for mesh fixation to repair a recurrent TLH. This technique may be particularly useful after previous failed attempts at open TLH repair.

  6. Ⅰ期手术经后路病灶清除内固定治疗儿童胸椎结核%One-stage debridement and bone grafting with internal fixation via posterior approach for treatment of children thoracic spine tuberculosis

    Institute of Scientific and Technical Information of China (English)

    蓝旭; 许建中; 罗飞; 刘雪梅; 葛宝丰

    2013-01-01

    目的:探讨Ⅰ期手术经后路结核病灶清除植骨融合内固定治疗儿童胸椎结核的效果.方法:2005年6月至2010年12月采用病灶清除植骨融合内固定治疗儿童胸椎结核9例,其中男7例,女2例;年龄3~12岁,平均7岁;病史3个月~1年,平均6个月.患儿均有不同程度胸背痛、肋间神经痛以及脊柱后凸畸形,同时伴有低热、盗汗、消瘦等全身症状.术前X线片、CT、MRI检查提示病变部位多发生于T4-T9节段.胸段后凸角35°~72°,平均48.2°.术前脊髓功能ASIA分级:B级2例,C级5例,D级2例.术后定期复查X线片了解后凸角变化和椎间植骨融合情况,采用ASIA分级评定术后脊髓功能恢复情况.结果:术中无大血管或脊髓损伤,术后随访16~38个月,平均24个月.所有患儿结核症状消失,无结核复发、切口感染、窦道形成或内固定失败等并发症,复查血沉正常.术后4~8个月复查X线片提示椎间植骨均获骨性愈合,内固定位置正常.最后随访后凸角12°~30°,平均19.5°,脊髓功能ASIA分级:C级2例,D级2例,E级5例.脊髓功能均有不同程度改善.结论:Ⅰ期经后路清除胸椎结核病灶彻底,椎管减压可靠,矫形效果显著,行自体或同种异体骨植骨钉棒系统内固定可有效重建胸段脊柱的稳定性.%Objective:To investigate the outcome of the children with thoracic spine tuberculosis who underwent radical debridement,reconstruction with bone autograft or allograft and internal fixation via posterior approach. Methods: From June 2005 to December 2010,9 children with thoracic spine tuberculosis underwent radical debridement,reconstruction with bone autograft or allograft and internal fixation via posterior approach including 7 males and 2 females with an average age of 7 years old ranging from 3 to 12 years. The course of the disease ranged from 3 months to 1 year (averaged 6 months). All the patients had continuous thoracic and back pain

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

    OpenAIRE

    2007-01-01

    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...

  8. The Role of Minimally Invasive Plate Osteosynthesis in Rib Fixation: A Review.

    Science.gov (United States)

    Bemelman, Michael; van Baal, Mark; Yuan, Jian Zhang; Leenen, Luke

    2016-02-01

    More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950's, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has become available suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation.

  9. Shape modifications of porous hydroxyapatite prostheses to improve rigid implant fixation: Experience in 12 cases

    Science.gov (United States)

    Rienzo, Alessandro Di; Iacoangeli, Maurizio; di Somma, Lucia G. M.; Alvaro, Lorenzo; Nocchi, Niccolò; Scerrati, Massimo

    2012-01-01

    Background: Various methods of fixation have been described for custom made hydroxyapatite cranial implants. Their poor malleability limits most of the common used fixation techniques because of the high risk of cranioplasty's fracturing or higher exposure to infections. We present our experience with a new fixation technique, based on an appositely premodified hydroxyapatite implants. Methods: In a 2-year time period, 12 patients underwent cranioplasty by a modified custom made porous hydroxyapatite implant. Once the three-dimensional computer model of the prostheses was performed, three semicircular extensions placed at strategic positions were drawn and the final prosthesis was realized. At surgery, holes fitting the extensions were drilled into the skull borders and the implant was easily embedded inside the defect. Small titanium meshes overlying the extensions were fixed by screws to the surrounding bone. Results: A minimal increase of operative times was recorded, with drilling and fixation requiring additional 30 and 15 minutes, respectively. Optimal contact between cranioplasty and skull borders was always observed at control computed tomography (CT) scans. Permanent rigid fixation was obtained in all cases, with good functional and aesthetic results at follow-up. Conclusions: Modifications of hydroxyapatite implants are obtained without additional costs. The minimal increase of operative times is largely counterbalanced by optimal fixation results. Finally, the bone drilling and the immediate proximity of bone to prosthesis might enhance the potential for osteogenesis and osteointegration. PMID:23372977

  10. 后路经伤椎固定联合伤椎及后外侧植骨治疗胸腰椎爆裂性骨折脊髓神经功能恢复研究%Study on posterior vertebral fixation combined with vertebral-posterolateral bone grafting in treatment of tho-racolumbar burst fractures

    Institute of Scientific and Technical Information of China (English)

    朱鑫; 徐海斌

    2015-01-01

    Objective To assess the clinical efficacy and safety for thoracolumbar fracture by the method of vertebral pedi‐cle screw fixation with transpedicular bone graft ,and consider its indications.Methods A total of 60 cases of patients with tho‐racolumbar unilateral or bilateral pedicle intact burst fracture ,were divided into the experimental group (posterior vertebral fix‐ation combined with vertebral bone posterolateral bone grafting) and control group (trauma with pedicle screw fixation and pos‐terolateral bone) with 30 cases in each group. We observed vertebral restoration degree (R) values (vertebral body height‘near the mean height of the anterior vertebral × 100% ) ,vertebral Cobb angle ,the fixed rate of complications ,spinal sequence re‐set ,neurological function recovery (Frankel score) in pre‐operation and at 1 week ,3 months ,12 months after opera‐tion.Results 60 cases were followed up for 12‐20 months (experimental group 16.4 ± 2.3 months;the control group of 16.1 ± 2.7 months). Vertebral fixation complications ,spinal sequence reset and neurological function recovery (Frankel score) were without statistical significance in pre‐operation and at 1 week ,3 months ,12 months after operation between the two groups (P>0.05). 12 months after operation ,two groups of Cobb angle and R value were statistically significant (P0.05). Conclusion Posterior vertebral fixation combined with vertebral‐posterolateral bone grafting in treatment of thoracolumbar burst fractures ,can effectively recover the support of the anterior column ,reduce the loss of the vertebral and kyphosis. The surgical methods in treatment of burst thora‐columbar fractures is a safe and effective method.%目的:探讨伤椎内植骨联合伤椎固定术治疗胸腰椎爆裂性骨折的安全性和临床疗效。方法将60例一侧或双侧椎弓根完好的胸腰椎爆裂性骨折患者,分为实验组(后路经伤椎固定联合伤椎植骨后外侧植骨)和

  11. A review of locking compression plate biomechanics and their advantages as internal fixators in fracture healing.

    Science.gov (United States)

    Miller, Danielle L; Goswami, Tarun

    2007-12-01

    Metallic implants are often involved in the open reduction and internal fixation of fractures. Open reduction and internal fixation is commonly used in cases of trauma when the bone cannot be healed using external methods such as casting. The locking compression plate combines the conventional screw hole, which uses non-locking screws, with a locking screw hole, which uses locking head screws. This allows for more versatility in the application of the plate. There are many factors which affect the functionality of the plate (e.g., screw placement, screw choice, length of plate, distance from bone, etc.). This paper presents a review of the literature related to the biomechanics of locking compression plates and their use as internal fixators in fracture healing. Furthermore, this paper also addresses the materials used for locking compression plates and their mechanical behavior, parameters that control the overall success, as well as inherent bone quality results.

  12. 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

    OpenAIRE

    J. Molina Montes; J. González-Lagunas; J. Mareque Bueno; J.A. Hueto Madrid; G. Raspall Martí

    2008-01-01

    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 use...

  13. Molecular Biology of Nitrogen Fixation

    Science.gov (United States)

    Shanmugam, K. T.; Valentine, Raymond C.

    1975-01-01

    Reports that as a result of our increasing knowledge of the molecular biology of nitrogen fixation it might eventually be possible to increase the biological production of nitrogenous fertilizer from atmospheric nitrogen. (GS)

  14. Human postmortem device retrieval and analysis--orthopaedic, cardiovascular, and dental systems.

    Science.gov (United States)

    Lemons, J; Brott, B; Eberhardt, A

    2010-01-01

    On the basis of decades of analyzing implant devices, tissues, and clinical records from revision surgical explants (called device failure), studies now include postmortem donors and in situ conditions (called success). A key issue has been information exchange from an interdisciplinary team where basic physical and biological studies complement details of the clinical conditions for each device. Overall, the summary information has shown that most revisions were based on factors associated with the patient health, disease, and compliance, with few outcomes directly correlated with technology and device-specific factors. However, because of the large numbers of devices implanted annually (millions), any sampling that reveals adverse circumstances could result in a high level of importance and the need for additional studies of this type. Experience from prior retrieval and analysis demonstrates significant value where peer reviewed results from investigations have altered the discipline and have improved the quality and longevity of health care associated with implanted devices. This report summarizes completed and ongoing studies of cardiovascular, dental, and orthopaedic systems. Endovascular stents from autopsies showed damage including fretting and corrosion from overlapping and intersecting conditions, plus some corrosion and element transfers to tissues from individual stents. Studies are proposed to increase numbers to evaluate clinical significance. Dental implants from postmortem donors that functioned more than 10 years provided evaluations of cobalt alloy devices and calcium phosphate bone graft substitutes originally investigated in the 1970s. Tissue integration and stability correlated with data from prior laboratory in vitro and in vivo investigations. Studies of articulation and fixation from orthopaedic total joint arthroplasties showed some limitations related to surface changes of YTZ zirconia, specific damage due to implantation procedures, which

  15. 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.

  16. Successful operative rib fixation of traumatic flail chest in a patient with osteogenesis imperfecta.

    Science.gov (United States)

    Kulaylat, Afif N; Chesnut, Charles H; Santos, Ariel P; Armen, Scott B

    2014-09-01

    Increasing attention has been directed towards operative rib fixation of traumatic flail chest; reported benefits include more rapid weaning from the ventilator, decreased intensive care unit stays, decreased complications and improved functional results. The outcomes of this surgical intervention in patients with osteogenesis imperfecta, a rare condition characterized by low bone density and bone fragility, are unknown. This case demonstrates that, in the management of traumatic flail chest in a patient with osteogenesis imperfecta, surgical fixation can be successful and should be considered early.

  17. Use of tightrope fixation in ankle syndesmotic injuries

    Institute of Scientific and Technical Information of China (English)

    Julian Maempel; Anthony Ward; Tim Chesser; Michael Kelly

    2014-01-01

    Objective:Conventional fixation of syndesmotic injuries with screws remains problematic.A novel fibrewire device (Tightrope(R)) has suggested advantages.However,small case series have reported high soft tissue complication rates.The purpose of our study was to quantify complication rates and further procedures in patients treated with Tightropes.A secondary objective was to determine incidence of complications and further procedures in those treated with syndesmotic screws over the same period.Methods:All patients undergoing syndesmotic fixation for ankle fracture between May 2008 and October 2009 were retrospectively reviewed.Incidence of complications,secondary procedures,maintenance of syndesmotic reduction and time spent on non-weight bearing were recorded.Family doctors were contacted for those treated with Tightropes to check for any complications managed elsewhere.Results:Thirty-five patients required syndesmotic fixation,in which 12 were treated with Tightropes.They were followed up in clinic for a mean of 12.4 weeks.Family doctors were contacted at mean 14.6 months after treatment to determine any complications suffered.There were no complications attributable to method of fixation.In this series,12 patients underwent 13 procedures and no patient had recurrent diastasis at discharge; 23 patients treated with screw fixation underwent 45 procedures (19 were screw removals).There was 1 case ofsyndesmotic diastasis.Screw removal resulted in 2 minor complications.Conclusion:Tightrope fixation provideds effective syndesmotic fixation that is maintained at discharge.We do not experience soft tissue complications reported elsewhere.

  18. Arthroscopic assisted percutaneous bone grafting and screw fixation for the treatment of lateral tibial plateau fractures:A 4-year follow-up%胫骨外侧平台骨折关节镜下经皮复位植骨螺钉内固定:4年随访★

    Institute of Scientific and Technical Information of China (English)

    曾润铭; 吴盛荣; 林少彬

    2013-01-01

      BACKGROUND: Studies have shown the knee secondary osteoarthritis may occur after the treatment of tibial plateau fractures with open reduction and internal fixation, but the researches on the middle- and long-term effect of arthroscopic assisted tibial plateau fracture fixation are stil rare. OBJECTIVE: To evaluate the outcomes of lateral tibial plateau fractures after treated with arthroscopic assisted percutaneous bone grafting and screw fixation for 1 and 4 years through clinical and radiological assessment. METHODS: Between March 2007 and March 2009, with the information of the patients with lateral tibial plateau fractures undergoing arthroscopic assisted percutaneous bone grafting and screw fixation were enrol ed. The data of the type of fractures in the Schatzker classification, the accompanying lesions of the cartilage defect on the lateral tibial plateau, the cartilage damage on the femoral condyle, intra-articular soft tissue lesions and insufficient reduction of the fracture, as wel as postoperative subsidence in the lateral tibial plateau were col ected. The Lysholm score, Ahlback osteoarthritis classification, Rasmussen function score and radiological score were assessed at 1 and 4 years after treated with percutaneous bone grafting and screw fixation. RESULTS AND CONCLUSION: Twenty-three patients finished the fol ow-up. At 1 and 4 years after percutaneous bone grafting and screw fixation, the mean Lysholm score was 90 and 87 points respectively (P=0.23), and the mean Rasmussen function score was 26 and 24 points respectively (P=0.30). At 4 years after surgery, 11 cases (47.8%) presented osteoarthritis and the Rasmussen radiological score was decreased from early postoperative 17.4 points to 4-year postoperatively 13.6 points (P=0.01). No correlation could be observed between the various types of fractures and their prognosis. The elder cases, cartilage damage and/or defect, intra-articular soft tissue lesions and postoperative subsidence in the

  19. Ultrastructural evaluation of shrinkage artefacts induced by fixatives and embedding resins on osteocyte processes and pericellular space dimensions.

    Science.gov (United States)

    Shah, Furqan A; Johansson, Bengt R; Thomsen, Peter; Palmquist, Anders

    2015-04-01

    The integrity of the interface between the osteocyte (Ot) process and the canalicular wall was investigated in terms of change in the lateral dimensions of the Ot process in relation to the canalicular width, i.e., widening of the pericellular space. This has been interpreted as shrinkage of the Ot process relative to the canalicular wall during sample preparation stages of fixation, dehydration, and resin embedding. Sprague-Dawley rat tibial cross-sections were prepared for transmission electron microscopy (TEM). Four different fixative preparations: paraformaldehyde (PF), modified Karnovsky's (MK), glutaraldehyde (GRR) with ruthenium red (GRR), and zinc formalin (ZF); and two different embedding resins: LR Gold (LRG) and Epon812 (Epon) were evaluated. It was found that for LRG embedding, formalin-only fixatives (PF and ZF) induced lower shrinkage than GRR-containing fixatives (MK and GRR). In contrast, for Epon embedding, MK showed the highest shrinkage, while no differences were found between the remaining fixatives (PF, ZF, and GRR). All formalin-containing fixatives (MK, PF, and ZF) induced similar shrinkage in both embedding media. The most dramatic difference was for GRR fixation, which in combination with LRG embedding showed ∼ 62% more shrinkage than with Epon embedding, suggesting that the combination of GRR fixation and LRG embedding synergistically amplifies Ot shrinkage. These differences likely suggest a role of the resin in secondarily influencing the tissue structure following fixation. Further, the work confirms LRG as a poor embedding medium for bone specimens, as it causes large variations in shrinkage depending on fixation.

  20. Lumbopelvic fixation: a surgical alternative for lumbar stability

    Directory of Open Access Journals (Sweden)

    Gabriel Virgilio Ortiz García

    2014-09-01

    Full Text Available OBJECTIVE: Lumbopelvic fixation is a valid surgical option to achieving great stability in cases where it is particularly demanded, such as in patients with poor quality bone, degenerative scoliosis, and revision surgeries with modern materials and techniques. It enables simple integration of the iliopelvic systems with the rest of the spinal structure, maintaining hemorrhagia at acceptable levels, as well as surgery time. METHODS: We analyzed a case series of 15 patients of our center, who required major construction and/or presented poor quality bone. RESULTS: A total of 15 patients was studied, of which 12 (80% were women and three (20%, men. Nine (60% of these were revision surgeries, maintaining a surgery time of 5 hours (±1 h, with average blood loss of 1380 ml (±178 ml. All the patients received six to eight transpedicular screws, including iliac screws, and in all cases, a bone graft was inserted. CONCLUSION: Lumbopelvic fixation in patients with characteristics associated with osteopenia and osteoporosis, and in major instrumentations, particularly revision surgeries, three-dimensional correction is achieved, constructing a strong, stable pelvic base that is very useful, in patients with fragile surgical anatomy, for changes of implant or extensive decompression, provided the arthrodesis technique is adequate and with the insertion of a sufficient bone graft, and obviously, taking care to maintain the sagittal balance.

  1. Disckectomy, Partial Adjacent Centrum Resection, Bone Graft with Titanium Mesh and Titanium Plate Fixation for the Treatment of Single Segment Cervical Disc Degeneration with Adjacent Vertebral Posterior Osteophyte%椎间盘及部分椎体切除加钛网植骨钛板内固定术治疗单节段颈椎椎间盘突出伴椎体后缘骨赘

    Institute of Scientific and Technical Information of China (English)

    孙继飞; 何强; 刘振利; 陈庆胜

    2012-01-01

    目的 评价颈椎椎间盘及相邻椎体部分切除加钛网植骨钛板内固定术治疗单节段颈椎椎间盘退变突出伴相邻椎体后缘骨赘的疗效. 方法 应用颈椎椎间盘及相邻椎体部分切除加钛网植骨钛板内固定术治疗单节段颈椎椎间盘退变突出伴相邻椎体后缘骨赘22例.取颈椎前路手术切口,术中仅切除突出的椎间盘及相邻椎体的1/3~ 1/2,使脊髓得到彻底的减压.再用填满碎骨的钛网植于骨缺损处加用钛板螺丝钉内固定,固定范围仅限于相邻椎体.术前和术后通过神经功能JOA评分、颈部轴性症状、颈椎动态侧位片和颈椎MRI比较临床疗效. 结果 均获随访,平均15(6 ~24)个月,术后JOA评分优良率86.4%,颈部轴性症状减轻,脊髓功能明显得到恢复.颈椎活动度良好.X线检查见钛网植骨及钛板内固定良好,未见不稳现象.MRI示颈髓压迫解除. 结论 颈椎椎间盘及相邻椎体部分切除加钛网植骨钛板内固定术治疗单节段颈椎椎间盘突出伴相邻椎体骨赘效果显著,可最大限度地保留颈椎节段的活动度.%Objective To evaluate the clinical effects of disckectomy, partial adjacent centrum resection , bone graft with titanium mesh and titanium plate fixation for the treatment of single segment cervical disc degeneration with adjacent vertebral posterior osteophyte. Methods There were 22 cases received this kind of surgical procedure. By anterior cervical incision, the herniated disc and only 1/3 to 1/2 of the adjacent vertebral body were removed for the decompression of the spinal cord. Then the titanium mesh filled with the small bones was implanted in the bone defect followed by titanium screw fixation. The fixation was limited to the adjacent vertebral bodies. Preoperative and postoperative neurological functions of the JOA score, the cervical axial symptoms, the cervical dynamic radiographs and cervical spine MRI were used to compare the clinical

  2. Development of Ion-Plasma Technology of Deposition of the Nanostructure Bactericidal Coatings on Orthopaedic Implantats and Fixative Devices. Production of Pilot Samples for Verification of their Use in Clinic

    Directory of Open Access Journals (Sweden)

    V.A. Belous

    2013-11-01

    Full Text Available Technology for creating coatings based on titanium oxide, which have pronounced antibacterial properties manifested upon X-ray and UV irradiation has been developed. Biological research showed that the obtained coatings are biocompatible and do not exert cytotoxic effect on cultured fibroblasts, cellular composition of subcutaneous fat and restructure of bone tissue. It is found that nanostructured coatings with anatase structure and thickness of ≥9 microns, implanted with molybdenum ions, have an optimum combination of properties. The department for the deposition of antibacterial coatings on orthopedic implants is created.

  3. Treatment of Lumbar Degenerative Disease with Unilateral Decompression,Bone Graft Fusion and Unilateral Pedicle Screw Fixation%经单侧减压融合、单边椎弓根螺钉内固定治疗腰椎退变性疾病

    Institute of Scientific and Technical Information of China (English)

    宋晋刚; 崔易坤; 苗艳; 尹振宇; 羊刚毅; 黄海锋

    2016-01-01

    目的:探讨经单侧行病变节段椎管减压、椎间植骨融合、单边椎弓根螺钉内固定治疗腰椎退变性疾病的临床疗效。方法我院2010年1月~2013年12月对35例腰椎退变性疾病采用经单侧减压、椎间植骨融合、单边椎弓根螺钉固定手术治疗。根据 JOA 评分法评估术后腰椎功能改善情况,采用视觉模拟评分(visual analog scale,VAS)评估术后疼痛缓解情况,腰椎正侧位 X 线片及 CT 扫描了解植骨融合情况。结果随访12~18个月,平均15个月。术前 JOA 评分(8.2±2.1)分,显著低于术后3个月(20.8±3.8)分(q =22.123,P <0.05)和术后12个月(21.7±3.9)分(q =23.703,P <0.05);VAS 评分术前(7.9±2.1)分,显著高于术后3个月(2.4±0.4)分(q =26.107,P <0.05)和12个月(2.3±0.3)分(q =26.582,P <0.05);JOA 评分和 VAS 评分随访期间无显著变化(P >0.05)。1年后椎间植骨融合率100%,未发现椎弓根螺钉松动、断裂、拔钉等异常。结论经单侧减压、椎间植骨融合联合单边椎弓根螺钉内固定治疗腰椎退变性疾病疗效满意,可在合适病例中推广应用。%Objective To investigate the clinical effects of unilateral vertebral canal decompression,intervertebral bone graft fusion,and unilateral pedicle screw fixation in the treatment of lumbar degenerative disease. Methods From January 2010 to December 2013,a total of 35 cases of lumbar degenerative disease were treated with unilateral decompression,intervertebral bone graft fusion,and unilateral pedicle screw fixation.The postoperative spine functions were evaluated with the JOA scores,the postoperative pain relief was evaluated with the VAS scores,and bone graft fusion was reviewed with lumbar X-ray and CT scanning. Results The patients were followed up for 12 -18 months (mean,15 months).The preoperative JOA scores (8.2 ±2

  4. 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

  5. Bone Biopsy

    Science.gov (United States)

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

  6. 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.

  7. The relationship between interfragmentary movement and cell differentiation in early fracture healing under locking plate fixation.

    Science.gov (United States)

    Miramini, Saeed; Zhang, Lihai; Richardson, Martin; Mendis, Priyan; Oloyede, Adekunle; Ebeling, Peter

    2016-03-01

    Interfragmentary movement (IFM) at the fracture site plays an important role in fracture healing, particularly during its early stage, via influencing the mechanical microenvironment of mesenchymal stem cells within the fracture callus. However, the effect of changes in IFM resulting from the changes in the configuration of locking plate fixation on cell differentiation has not yet been fully understood. In this study, mechanical experiments on surrogate tibia specimens, manufactured from specially formulated polyurethane, were conducted to investigate changes in IFM of fractures under various locking plate fixation configurations and loading magnitudes. The effect of the observed IFM on callus cell differentiation was then further studied using computational simulation. We found that during the early stage, cell differentiation in the fracture callus is highly influenced by fracture gap size and IFM, which in turn, is highly sensitive to locking plate fixation configuration. The computational model predicted that a small gap size (e.g. 1 mm) under a relatively flexible configuration of locking plate fixation (larger bone-plate distances and working lengths) could experience excessive strain and fluid flow within the fracture site, resulting in excessive fibrous tissue differentiation and delayed healing. By contrast, a relatively flexible configuration of locking plate fixation was predicted to improve cartilaginous callus formation and bone healing for a relatively larger gap size (e.g. 3 mm). If further confirmed by animal and human studies, the research outcome of this paper may have implications for orthopaedic surgeons in optimising the application of locking plate fixations for fractures in clinical practice.

  8. 内窥镜辅助下前路经寰枢关节螺钉固定植骨融合术治疗上颈椎不稳%Endoscopy-assisted anterior transarticular screw fixation and bone grafting for upper cervical instability

    Institute of Scientific and Technical Information of China (English)

    姚女兆; 王文军; 王麓山; 晏怡果; 李学林; 欧阳智华

    2012-01-01

    目的:探讨内窥镜辅助下前路经寰枢关节螺钉固定植骨融合术治疗上颈椎不稳的临床可行性及其疗效.方法:2006年1月至2009年12月采用内窥镜辅助下前路经寰枢关节螺钉固定植骨融合术治疗上颈椎不稳患者13例,男8例,女5例;年龄17~65岁,平均46.8岁.JeffersonⅡ型骨折6例,JeffersonⅢ型骨折1例,寰枢椎脱位3例,陈旧性齿状突骨折3例.患者均有枕颈部不适和活动受限,术前VAS评分为3.2~4.1分,平均3.8分;2例伴有不同程度脊髓功能损害者,按Frankel分级C级1例,D级1例.随访患者临床症状改善和植骨融合情况.结果:均在内镜辅助下顺利完成手术,13例患者共置入26枚螺钉;手术时间60~130min,平均80min;术中出血110~290ml,平均190ml.术中无脊髓、椎动脉损伤等并发症.术后复查CT显示1枚螺钉位置欠佳,螺钉外斜角偏小且上斜角偏大,螺钉部分进入椎管,但未损伤脊髓,未做处理;25枚位置良好.寰枢关节基本复位,固定可靠.术后随访12~60个月,平均18个月,末次随访时VAS评分降至1.0~2.0分,平均1.3分,与术前比较有统计学差异(P<0.05).2例伴颈髓损伤患者的症状均有改善,Frankel分级C级者恢复到D级,D级者恢复到E级.12例患者术后3个月开始出现植骨融合,末次随访时寰枢关节间隙植骨均达到融合;1例患者未见明显植骨融合,但寰枢关节稳定性良好,未出现断钉等并发症.结论:内窥镜辅助下前路经寰枢关节螺钉固定植骨融合术治疗上颈椎不稳是可行的,能取得较好的治疗效果,且在一定程度上克服了传统手术显露困难的缺点,从而减少手术并发症.%Objectives: To evaluate the operation method and clinical outcome of atlantoaxial joint fusion using endoscopy-assisted anterior transarticular screw fixation and bone grafting for upper cervical instability. Methods: 13 cases with upper cervical instability who underwent anterior release

  9. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Densitometry (DEXA) Bone densitometry, also called dual-energy ... limitations of DEXA Bone Densitometry? What is a Bone Density Scan (DEXA)? Bone density scanning, also called ...

  10. Double calcaneal osteotomy with percutaneous Steinmann pin fixation as part of treatment for flexible flatfoot deformity: a review of consecutive cases highlighting our experience with pin fixation.

    Science.gov (United States)

    Boffeli, Troy J; Abben, Kyle W

    2015-01-01

    Surgical correction of flexible flatfoot deformity and posterior tibial tendon dysfunction has been extensively reported in published studies. When appropriate, calcaneal osteotomies for flatfoot correction have been a favorite of foot and ankle surgeons because of the corrective power achieved without the need to fuse any rearfoot joints. The medial displacement calcaneal osteotomy and Evans calcaneal osteotomy, together termed the double calcaneal osteotomy, have been reported several times by various investigators with a wide variety of fixation options. We undertook an institutional review board-approved retrospective review of 9 consecutive patients (11 feet), who had undergone double calcaneal osteotomy with 2 percutaneous Steinmann pin fixation for the correction of flexible flatfoot deformity, with or without posterior tibial tendon dysfunction. All patients had radiographic evidence of bone healing of the posterior calcaneal osteotomy and incorporation of the Evans osteotomy bone graft at 6 weeks and demonstrated clinical healing at 6 weeks. All patients had 2 percutaneous Steinmann pins placed through both osteotomies, and these were removed an average of 6 weeks postoperatively. No patient developed pin site complications. The only complication noted was sural neuritis, which was likely incision related. No patients had delayed union or nonunion, and we did not identify any graft shifting postoperatively. The present retrospective series highlights our experience with 2 percutaneous Steinmann pin fixation, demonstrating equal or better results than many previous published fixation methods for double calcaneal osteotomy. It is cost-effective and minimizes the potential risk of iatrogenic Achilles pathologic features associated with screw fixation.

  11. 21 CFR 872.3930 - Bone grafting material.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification... “Class II Special Controls Guidance Document: Dental Bone Grafting Material Devices.” (See § 872.1(e) for... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone grafting material. 872.3930 Section...

  12. Digital electronic bone growth stimulator

    Energy Technology Data Exchange (ETDEWEB)

    Kronberg, James W. (Aiken, SC)

    1995-01-01

    A device for stimulating bone tissue by applying a low level alternating current signal directly to the patient's skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures.

  13. Digital electronic bone growth stimulator

    Energy Technology Data Exchange (ETDEWEB)

    Kronberg, J.W.

    1995-05-09

    A device is described for stimulating bone tissue by applying a low level alternating current signal directly to the patient`s skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures. 5 figs.

  14. Prevention of Thumb Web Space Contracture With Multiplanar External Fixation.

    Science.gov (United States)

    Harper, Carl M; Iorio, Matthew L

    2016-09-01

    Thumb web space contracture following hand trauma can be disabling with numerous reconstructive procedures existing to correct the resultant deformity. Following marked soft tissue injury to the hand we utilized the Stryker Hoffmann II Micro External Fixator System to link the first and second metacarpals by a multiplanar system using 1.6 or 2.0 mm self-drilling half-pins and 3 mm carbon fiber connecting rods. This facilitated placement of the thumb in maximal palmar abduction as well as allowed adjustment of thumb position throughout the postoperative period. This technique was performed on 5 patients. Two patients were treated with a first web space external fixator for table saw injuries to the radial aspect of the hand. An additional 2 patients were treated with a first web space external fixator following metacarpophalangeal joint capsular release in the setting of thermal burns. A fifth patient underwent second ray amputation, trapeziectomy and trapezoidectomy for squamous cell carcinoma with subsequent stabilization with the external fixator. The external fixator was left in place until soft tissues were healed (average 5.5 wk). The patients were allowed to mobilize their hand in as much as the external fixator allowed, and no device-associated complications were noted. Thumb web space was preserved with passive and supple thumb circumduction and web space abduction/adduction in all patients at an average follow-up of 5 months. The average Quick Dash Score was 35±5 and the average Modern Activity Subjective Survey of 2007 was 30±8.

  15. Ankle fusion stability: a biomechanical comparison of external versus internal fixation.

    Science.gov (United States)

    Hoover, Justin R; Santrock, Robert D; James, William C

    2011-04-11

    This biomechanical study compares bimalleolar external fixation to conventional crossed-screw construct in terms of stability and compression for ankle arthrodesis. The goals of the study were to determine which construct is more stable with bending and torsional forces, and to determine which construct achieves more compression.Fourth-generation bone composite tibia and talocalcaneal models were made to 50th percentile anatomic specifications. Fourteen ankle fusion constructs were created with bimalleolar external fixators and 14 with crossed-screw constructs. Ultimate bend, torque, and compression testing were completed on the external fixator and crossed-screw constructs using a multidirectional Materials Testing Machine (MTS Systems Corp, Eden Prairie, Minnesota). Ultimate bend testing revealed a statistically significant difference (P=.0022) with the mean peak load to failure for the external fixator constructs of 973.2 N compared to 612.5 N for the crossed-screw constructs. Ultimate torque testing revealed the mean peak torque to failure for the external fixator construct was 80.2 Nm and 28.1 Nm for the crossed-screw construct, also a statistically significant difference (P=.0001). The compression testing yielded no statistically significant difference (P=.9268) between the average failure force of the external fixator construct (81.6 kg) and the crossed-screw construct (81.2 kg).With increased stiffness in both bending and torsion and comparable compressive strengths, bimalleolar external fixation is an excellent option for tibiotalar ankle arthrodesis.

  16. 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

  17. External fixation combined with limited internal fixation for Pilon fractures%外固定支架结合有限内固定治疗Pilon骨折

    Institute of Scientific and Technical Information of China (English)

    周淮; 徐晓军

    2011-01-01

    Objective To investigate the clinical effect of Pilon fractures treated with external fixation and limited internal fixation.Methods 24 cases of Pilon fractures of tibia were treated with external fixation combined limited internal fixation.Results 24 cases were followed up for 10 ~ 20 months.No bone nonumon or skin necrosis complication was found.According to Mazur ankle joint scoring system, the results were excellent in 14, good in 7 , and fair in 3.Conclusions External fixation combined with limited internal fixation can immohilize the sections of fracture and achieve excellent ankle joint function,so it is an effective surgical treatment of Pilon fractures.%目的 探讨外固定支架结合有限内固定治疗Pilon骨折的疗效.方法 采用外固定支架结合有限内固定治疗24例Pilon骨折.结果 24例均获得随访,时间10~20个月.无骨不连、皮肤坏死发生.踝关节功能Mazur评分:优14例,良7例,可3例.结论 外固定支架结合有限内固定可以获得术后骨折稳定,取得良好踝关节功能,是治疗Pilon骨折有效的手术方案.

  18. First metatarsophalangeal joint arthrodesis: current fixation options.

    Science.gov (United States)

    Moon, Jared L; McGlamry, Michael C

    2011-04-01

    This article reviews the current literature on first metatarsophalangeal joint arthrodesis rates using various forms of fixation, as well as reviewing biomechanical studies comparing the strengths of the different fixation options that are available.

  19. 颅脑外伤术后头部固定装置的研制%Research and Development of a Head Fixation Device for Post-Operative Patients with Cranio-Cerebral Trauma

    Institute of Scientific and Technical Information of China (English)

    王学建

    2015-01-01

    针对颅脑外伤术(尤其是枕部手术)后头部切口不易保护、包扎易松动、易致切口污染等问题,本文研制了一款神经外科头部固定装置,该装置主要由头部包扎部分及可拆卸保护装置等结构构成,具有包扎牢固、舒适、切口保护等功能,可解决头部外伤术后包扎的问题。临床实际应用证实其具有省时、方便、实用、舒适等效果,值得临床推广。%In view of the issues occurring after cranio-cerebral trauma surgeries, especially occipital surgeries, including difficulty in incision protection, loose dressing, and incision pollution, a kind of neurosurgery head ifxation device was researched and developed, which mainly consisted of the head bandage and removable protection structure. With the functions of steady and comfortable bandage as well as incision protection, the device was intended to solve the problem of incision protection after head trauma surgeries. Clinical application proved its time-saving, easy-to-use, practical and comfortable features, deserving wider clinical promotion.

  20. Surgical treatment of neglected clubfoot using external fixator

    Directory of Open Access Journals (Sweden)

    Rodrigo Mota Pacheco Fernandes

    Full Text Available ABSTRACT The definition of neglected clubfoot (NC includes a variable range of complex deformities of the foot that are refractory to conventional treatments or are treated inappropriately. Several etiologies may be related to this. The Ilizarov method has become established as a tool for treating these deformities. It minimizes soft-tissue damage through gradual correction of the deformity, with a high success rate in relation to achieving a plantigrade foot, with low incidence of recurrence. The indications for treatment include severe rigid deformities (Dimeglio III and IV, or adverse skin conditions. Careful clinical and radiological examination is fundamental for proper planning and installation of the external fixator. The techniques used include selection of external fixation assemblies, which can be closed when there is a connection between the leg, hindfoot and forefoot. This closed assembly may or may not be constricted, according to whether hinges are provided or whether use of the natural anatomical hinges during correction of the deformity is envisaged. An open assembly makes it possible to add flexibility to the foot through histogenesis, while allowing closed corrections of greater precision later on. Hexapod fixators are an innovation with high potential for accuracy in correcting deformities. Procedures associated with external fixation include soft-tissue release and bone procedures. These procedures enable corrections that are more anatomical, for different degrees of severity and stiffness of deformity. It can be concluded from analyzing this case series that treatment of neglected clubfoot using an external fixator has a high rate of good and excellent results, with low frequency of complications.

  1. Sistemas osso-implante ex vivo utilizando haste intramedular polimérica para imobilização de fraturas femorais em bovinos jovens Ex vivo bone-implant systems using polymeric intramedullary nails for fixation of femoral fractures in young calves

    Directory of Open Access Journals (Sweden)

    Odael Spadeto Junior

    2011-02-01

    Full Text Available O desenvolvimento de novos aparatos usando materiais disponíveis e de baixo custo pode ser uma alternativa viável para o tratamento cirúrgico de fraturas em ossos longos de bovinos. O objetivo deste estudo foi avaliar a resistência mecânica de fêmures de bovinos jovens com fratura diafiseal, imobilizados com hastes intramedulares bloqueadas, compostas por diferentes polímeros. Para tanto, testes físicos de compressão e flexão, por meio de uma máquina universal de ensaios foram realizados em quatro grupos distintos de seis fêmures obtidos de bovinos jovens. Em um dos grupos, os ossos foram mantidos íntegros (grupo controle, enquanto que os outros os ossos, foram fraturados e imobilizados com uma haste intramedular bloqueada, composta por polipropileno, poliacetal ou poliamida (uma para cada grupo. Independente do polímero utilizado, nenhuma das hastes estudadas ofereceu aos fêmures fraturados resistência comparável ao osso íntegro, quando consideradas em conjunto as forças de flexão e compressão. A concordância desses achados com resultados in vivo previamente publicados, demonstra que a metodologia utilizada para testes ex vivo pode ser útil na seleção de materiais mais resistentes para confecção de novos modelos.The development of new devices using available and low cost materials may be an useful alternative for the treatment of long bone fractures in large animals. The aim of this study was to evaluate the mechanical strength of young bovine femur with diaphyseal fracture fixed with different polymeric intramedullary nails. Bending and compression tests using a universal machine were carried out in 4 distinct groups of 6 femurs from young calves. In one of the groups bones were intact while in the other three fractured bones were fixed using an intramedullary nail made of polypropylene, polyacetal or polyamide (one for each group. Considering bending and compression tests together, none of the used polymers offered

  2. Computer assisted preoperative planning of bone fracture reduction: Simulation techniques and new trends.

    Science.gov (United States)

    Jiménez-Delgado, Juan J; Paulano-Godino, Félix; PulidoRam-Ramírez, Rubén; Jiménez-Pérez, J Roberto

    2016-05-01

    The development of support systems for surgery significantly increases the likelihood of obtaining satisfactory results. In the case of fracture reduction interventions these systems enable surgery planning, training, monitoring and assessment. They allow improvement of fracture stabilization, a minimizing of health risks and a reduction of surgery time. Planning a bone fracture reduction by means of a computer assisted simulation involves several semiautomatic or automatic steps. The simulation deals with the correct position of osseous fragments and fixation devices for a fracture reduction. Currently, to the best of our knowledge there is no computer assisted methods to plan an entire fracture reduction process. This paper presents an overall scheme of the computer based process for planning a bone fracture reduction, as described above, and details its main steps, the most common proposed techniques and their main shortcomings. In addition, challenges and new trends of this research field are depicted and analyzed.

  3. 四肢长骨干骨折治疗的有限接触动力加压钢板和动力加压钢板临床比较%Clinical comparison of dynamic compression plate and limited contact dynamic compression plate fixation in the treatment of limbs long bone fracture

    Institute of Scientific and Technical Information of China (English)

    张星华

    2014-01-01

    目的 对比动力加压钢板(DCP)与有限接触动力加压钢板(LC-DCP)内固定治疗四肢长骨干骨折的临床疗效,为临床内固定的选择提供一定依据.方法 回顾性分析采用DCP和LC-DCP内固定治疗的172例四肢长骨干骨折患者的临床资料.其中LC-DCP组101例,DCP组71例,比较两组手术时间、术中出血量、住院时间、骨折愈合时间、骨折不愈合发生率、日常活动能力和关节功能评分及临床疗效.结果 LC-DCP组手术时间、骨折愈合时间、骨折不愈合发生率均优于DCP组[(62±13) min比(88±20) min、(60.0±20.5)d比(85.0±25.5)d、1.0%(1/101)比7.0%(5/71)],差异有统计学意义(P<0.05),而两组术中出血量与住院时间比较差异无统计学意义(P>0.05).LC-DCP组Barthel和Harris评分分别为(72.61±8.63)分和(69.28±7.63)分,均优于DCP组的(52.58±5.53)分和(55.07±6.26)分,差异有统计学意义(P<0.05).LC-DCP组优良率优于DCP组[99.0%(100/101)比90.1%(64/71)],差异有统计学意义(x2=15.71,P<0.01).结论 四肢长骨干骨折采用LC-DCP治疗,能提高临床疗效,减少手术并发症,提高患者的日常关节功能,值得临床推广使用.%Objective To compare the clinical effect of dynamic compression plate (DCP) and limited contact dynamic compression plate (LC-DCP) fixation in the treatment of limbs long bone fracture,provide certain basis for the choice of clinical internal fixation.Methods The clinical data of 172 patients with limbs long bone fracture treated with DCP and LC-DCP fixation were retrospectively analyzed.One hundred and one cases in LC-DCP group,and 71 cases in DCP group,the operation time,intraoperative blood loss,hospitalization time,fracture healing time,incidence of nonunion,daily activity ability and joint function score and clinical curative effect in two groups were compared.Results The operation time,fracture healing time,incidence of nonunion in LC-DCP group were better than those in DCP

  4. 皮质骨螺钉内固定治疗下胫腓联合分离的 CT 研究%Internal fixation with cortical bone screws for the treatment of distal tibiofibular syndesmosis separation:a CT study of 32 patients

    Institute of Scientific and Technical Information of China (English)

    鲁建作; 林央央; 杨杰; 董晓敏

    2015-01-01

    Objective:To explore the effect of internal fixation with cortical bone screws on the distal tibiofibular syndesmosis. Methods:The clinical records of 32 patients who were treated with cortical bone screws internal fixation for distal tibiofibular syndesmosis were analyzed retrospectively.The patients consisted of 18 males and 14 females,and ranged in age from 28 to 64 years (Median =43.5 yrs).The distal tibiofibular syndesmosis separation located in left leg for 14 cases and right leg for 18 cases.According to the Danis -Weber classification,the injuries belonged to types B(12)and C(20).Fibula fracture combined with posterior malleolus injury and medial malleolus injury or deltoid ligament injury were found in 11 patients,and fibula fracture combined with medial malleolus injury or deltoid ligament injury were found in 21 patients.Bilateral distal tibiofibular transverse CT films were taken in all patients.The tibiofibula congru-ence angle,fibular outward displacement and backward displacement relative to peroneal sinus of tibia were measured on the CT films and were analyzed.Results:The tibiofibula congruence angle and fibular outward displacement relative to peroneal sinus of tibia of affected side were less than those of uninjured side(68.66 +/-9.28 vs 79.49 +/-14.66 degrees,t =2.998,P =0.025;5.65 +/-1.79 vs 7.66 +/-2.05 mm,t =2.131,P =0.012),while fibular backward displacement relative to peroneal sinus of tibia of affected side was greater than that of uninjured side(4.94 +/-1.49 vs 1.90 +/-3.34 mm,t =14.089,P =0.002).Conclusion:After cortical bone screws internal fixa-tion for the treatment of distal tibiofibular syndesmosis separation,there is a trend for anteromedial rotation of distal tibiofibular syndesmosis of affected side compared to uninjured side.%目的:探讨皮质骨螺钉内固定对下胫腓联合的影响。方法:回顾性分析32例行皮质骨螺钉内固定术治疗的下胫腓联合分离患者的临床资料,男18例、女14

  5. The treatment of AO type C fractures of the distal radius with dynamic external fixation combined with minimally invasive reset and bone gratting and locking compression plate%动力型外固定支架结合微创复位植骨与锁定钢板内固定治疗桡骨远端骨折的比较研究

    Institute of Scientific and Technical Information of China (English)

    付炳金; 朱晓东

    2014-01-01

    reset and bone grafting and open reduction combined with locking compression plate internal fixation .To evaluate the merit and demerit of the two methods .Methods From September 2010 to March 2014 , we choose 62 cases with AO type C2 and C3 fractures of the distal radius ,and make a retrospective study of these patients'fol-low -up data .32 cases were treated with dynamic external fixation combined with minimally invasive reset and bone grafting , 30 cases were treated with open reduction combined with locking compression plate internal fixation .Collected and sorted out the patients'X-ray measurement data ,the common surgery complications ,as well as the wrists'Gartland-Werley function scores ,for statistical analysis .Results 62 cases of distal radius fractures have received bone healing .After surgeries ,the com-mon surgery complications showed that ,in the external fixation group ,nail track infection 2 ,wrist joint pain 1 ,wrist joint stiffness 1;whilein the LCP group ,wound infection 2 ,wrist joint pain 2 .At 24 months after the treatments ,the wrists'Gart-land-Werley function scores showed that ,in the external fixation group ,excellent /good 28;whilein the LCP group ,excel-lent /good 28 .After statistical analysis ,The external fixation group and the LCP group was pointless to cast (P>0.05) .Con-clusions The treatment of AO type C2 and C3 fractures of the distal radius with dynamic external fixation combined with mini-mally invasive reset and bone grafting is an effective method .This method is simple ,less invasive .It can effectively correct the shortening deformity and angular deformity of the distal radius ,making an anatomical reduction of the distal radius fractures , and increasing the stability of the fractures .The treatment of AO type C2 and C3 fractures of the distal radius with locking com-pression plate is an effective method ,too .This surgery has a good reset effect ,and a high fixation strength .It can effectively avoid reset losing of the

  6. 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

  7. Combining of small fragment screws and large fragment plates for open reduction and internal fixation of periprosthetic humeral fractures.

    Science.gov (United States)

    Seybold, Dominik; Citak, Mustafa; Königshausen, Matthias; Gessmann, Jan; Schildhauer, Thomas A

    2011-10-01

    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 für 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.

  8. Experimental model for the study of soft tissue fixation methods on skin-pericranium flaps in rats

    OpenAIRE

    Cavazana,William César; Cuman, Roberto Kenji Nakamura; Takeshita, Wilton Mitsunari; Passeri, Luis Augusto

    2013-01-01

    PURPOSE: To develop an experimental model to study and radiologically monitor displacement of skin flaps in the pericranium of rats subjected to traction and surgical fixation using suture anchored in a skull bone tunnel or with N-butyl-2-cyanoacrylate (HistoacrylTM) surgical adhesive. METHODS: Radiological markers were placed in the subcutis of Wistar rats undergoing subperiosteal detachment of the pericranium with pulling and fixation of the flap. We performed radiography on postoperative d...

  9. Mechanical Comparison of Headless Screw Fixation and Locking Plate Fixation for Talar Neck Fractures.

    Science.gov (United States)

    Karakasli, Ahmet; Hapa, Onur; Erduran, Mehmet; Dincer, Cemal; Cecen, Berivan; Havitcioglu, Hasan

    2015-01-01

    For talar neck fractures, open reduction and internal fixation have been thought to facilitate revascularization and prevent osteonecrosis. Newer screw systems allow for placement of cannulated headless screws, which provide compression by virtue of a variable pitch thread. The present study compared the biomechanical fixation strength of cannulated headless variable-pitch screw fixation and locking plate fixation. A reproducible talar neck fracture was created in 14 fresh cadaver talar necks. Talar head fixation was then performed using 2 cannulated headless variable-pitch 4-mm/5-mm diameter (4/5) screws (Acutrak; Acumed, Hillsboro, OR) and locking plate fixation. Headless variable-pitch screw fixation had lower failure displacement than did locking plate fixation. No statistically significant differences were found in failure stiffness, yield stiffness (p = .655), yield load (p = .142), or ultimate load between the 2 fixation techniques. Cannulated headless variable-pitch screw fixation resulted in better failure displacement than locking plate fixation in a cadaveric talus model and could be considered a viable option for talus fracture fixation. Headless, fully threaded, variable-pitch screw fixation has inherent advantages compared with locking plate fixation, because it might cause less damage to the articular surface and can compress the fracture for improved reduction. Additionally, plate fixation can increase the risk of avascular necrosis owing to the wider incision and dissection of soft tissues.

  10. Effect of induced aniseikonia on fixation performance.

    Science.gov (United States)

    Remole, A

    1988-01-01

    The purpose of the study was to determine to what extent induced aniseikonia affects fixation performance. Aniseikonia was induced in the vertical meridian only, whereas fixation alignment was monitored in the horizontal meridian. A previously developed technique based on the dependency of border enhancement bandwidth on fixation eccentricity was used to monitor deviations from central fixation during fusion. Stress on the fusion mechanism was supplied by controlled increments of forced horizontal vergence. It was found that deviation from central fixation in the horizontal meridian generally increases with increasing amounts of vertical aniseikonia. The effect is particularly pronounced for small amounts of aniseikonia.

  11. Bone within a bone

    Energy Technology Data Exchange (ETDEWEB)

    Williams, H.J.; Davies, A.M. E-mail: wendy.turner@roh.nhs.uk; Chapman, S

    2004-02-01

    The 'bone within a bone' appearance is a well-recognized radiological term with a variety of causes. It is important to recognize this appearance and also to be aware of the differential diagnosis. A number of common conditions infrequently cause this appearance. Other causes are rare and some remain primarily of historical interest, as they are no longer encountered in clinical practice. In this review we illustrate some of the conditions that can give the bone within a bone appearance and discuss the physiological and pathological aetiology of each where known.

  12. DISTRACTION OF OSTEOGENESIS AND LENGTHENING OF CRANIOFACIAL BONE-PRELIMINARY REPORT OF AN EXPERIMENTAL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective The method of bone lengthening by distraction of callus was used on dog mandible as a model to study the capability and changes of membranous bone during distraction osteogenesis. Methods 15 dogs aged 5~7 months were chosen as the subjects. The operation included a unilateral or bilateral periosteal preserving corti cotomy of mandibular bone, and an introral mini lengthening device were fixed to the buccal side of the mandible. After 7d, the mandible was lengthened lmm/d for 20d and then held in internal fixation for 7~ 140d (1 ~ 20 weeks). Results The dogs were killed at 3 times. Anthropometric measurements, X-ray examination and histological observa tion were conducted and conformed that the distracted bone had formed in the expanded zone successfully. Conclu sion The results suggested that we could use the DO technique in the area of craniofacial clinic. The strong ability of generating new bone in membranous skeleton by DO technique should be further demonstrated in the future.

  13. 一期前路病灶清除植骨重建钛板内固定术治疗腰骶段脊柱结核%Clinical efficacy of one-stage anterior debridement, bone graft and reconstruction titanium plate internal fixation in treating lumbosacral spinal tuberculosis

    Institute of Scientific and Technical Information of China (English)

    夏曦; 唐绍锋; 曹志武; 王辉; 姚女兆; 王文军

    2016-01-01

    Objective To evaluate clinical outcomes following one-stage anterior radical debridement, interbody fusion, and reconstruction titanium plate internal fixation for the treatment of lumbosacral spinal tuberculosis.Methods The clinical data of 30 patients(17 males and 13 females,aged range from 27 to 65 years, mean 37. 5 years) with tuberculosis of the lumbosacral segments(including L5 -S1 ) who were treated with anterior radical debridement, autologous iliac bone graft,and internal fixation with reconstruction titanium plate at Department of Spinal Surgery of the First Affiliated Hospital of University of South China from August 2011 to August 2014 were retrospectively reviewed. All patients routinely received antitubercular drugs for 2 to 3 weeks before operation. Operation was performed when the general condition improved. All patients were systematically and routinely treated with antituberculous drug for 12-18 months after operation. The preoperative, 3 months after operation, last follow up erythrocyte sedimentation rate ( ESR) , C reactive protein( CRP) , visual analog scale ( VAS) , as well as Oswestry disability index ( ODI) were analyzed.Results Thirty patients were followed up for 12-36 months,mean 18 months.At last follow-up, no lower limb radiation pain and tuberculosis recurrence were found in all cases. The VAS scores were significantly decreased from 7. 8 ± 1. 7 at preoperation to 1. 7 ± 0. 6 at 3 months after operation, and 1.5±0.5 at last follow-up(all P values0.05).Conclusions Based on systemic and routine antituberculosis treatment,the surgical treatment of lumbosacral spinal tuberculosis with one-stage anterior debridement, bone graft and reconstruction titanium plate internal fixation have a direct and safe access to lesions of lumbosacral tuberculosis, and eradicate tuberculosis kitchen, reconstruct spinal stability and achieve good clinical outcome.%目的:探讨一期前路结核病灶清除植骨重建钛板内固定治疗腰骶段脊

  14. Curative effect of anatomical Ti-plate fixation combining with bone graft in the treatment of intra-articular calcaneal fractures%解剖型跟骨钛板并植骨治疗跟骨关节内骨折的临床疗效

    Institute of Scientific and Technical Information of China (English)

    王怀斌; 袁志; 裴国献; 刘建; 毕龙; 王连军; 孙克理; 隋天棋

    2014-01-01

    Objective To investigate the curative effect of anatomical Ti-plate combined with bone graft in treatment of intra-articular calcaneal fractures .Methods Retrospective analysis was conducted in 25 patients with 33 feet from Mar.2009 to May 2012,who were diagnosed as Sanders typeⅡ-Ⅳintra-articular calcaneal fractures .There were 20 males(26 feet) and 5 females (7 feet) with average age of (36.16 ±14.63)years(ranged from 15 to 65 years old) .There were 17 cases of single foot injury and 8 cases of double feet injury .All the patients were treated with Ti-plate fixation combined with bone graft and their calcaneal anatomic forms were recovered during operation .Mary-land foot score was used to evaluate the postoperative function .Results All the 25 cases (33 feet) were followed up for 12-36 months,with a mean time of 19.3 months.According to Maryland foot score ,17 feet were rated as excellent , 12 feet as good,4 feet as moderate.The excellent and good rate was 87.88 %.Conclusion Anatomical Ti-plate combined with bone graft for treatment of intra-articular calcaneal fractures can restore the smoothness of subtalar joint surface,help patients take earlier functional exercise and obtain a reliable curative effect .%目的:探讨解剖型跟骨钛板并植骨治疗跟骨关节内骨折的临床疗效。方法选择2009年3月~2012年5月期间收治的25例(33足)SanderslⅡ~Ⅳ型跟骨关节内骨折患者,男性20例(26足),女性5例(7足);年龄15~65岁,平均(36.16±14.63)岁。单足17例,双足8例,采用切开复位解剖型跟骨钛板内固定并植骨进行治疗,术中恢复跟骨解剖形态,按Maryland足部评分系统进行术后功能评分,评价手术效果,进行系统的回顾性总结分析。结果本组25例(33足)术后均获12~36个月随访(平均19.3个月),按Maryland足部评分标准:优17足、良12足、可4足,差0足;优良率为87.88%。

  15. Evaluation of pediatric lower extremity fractures managed with external fixation: outcomes in a deployed environment.

    Science.gov (United States)

    Eichinger, Josef K; McKenzie, Colin S; Devine, John G

    2012-01-01

    External fixation of pediatric lower extremity fractures is usually reserved for severe, open fractures in polytraumatized patients, but it is often the only available treatment option for deployed military surgeons. We analyzed the outcomes and complications of 17 consecutive pediatric long bone fractures treated with external fixation at a Forward Surgical Team facility in an austere environment during Operation Enduring Freedom in Afghanistan during a 12-month period. Treatment consisted of uniplanar external fixation for 12 femoral shaft fractures (11 closed), 4 tibial shaft fractures (all open), and 1 subtrochanteric fracture (closed) in 14 males and 3 females with an average age of 7.4 years. All 17 fractures went on to union with no incidences of refracture. Complications included 1 broken pin and 3 pin site infections treated with wound care and oral antibiotics. In a deployed environment, external fixation is the treatment method of choice for lower extremity fractures by virtue of patient, environment, equipment, and mission factors. This case series validates the usage of a simple, uniplanar external fixator for a variety of open and closed pediatric long bone fractures as evidenced by the successful union rate and low number of complications.

  16. 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

  17. Nitrogen fixation by marine cyanobacteria.

    Science.gov (United States)

    Zehr, Jonathan P

    2011-04-01

    Discrepancies between estimates of oceanic N(2) fixation and nitrogen (N) losses through denitrification have focused research on identifying N(2)-fixing cyanobacteria and quantifying cyanobacterial N(2) fixation. Previously unrecognized cultivated and uncultivated unicellular cyanobacteria have been discovered that are widely distributed, and some have very unusual properties. Uncultivated unicellular N(2)-fixing cyanobacteria (UCYN-A) lack major metabolic pathways including the tricarboxylic acid cycle and oxygen-evolving photosystem II. Genomes of the oceanic N(2)-fixing cyanobacteria are highly conserved at the DNA level, and genetic diversity is maintained by genome rearrangements. The major cyanobacterial groups have different physiological and ecological constraints that result in highly variable geographic distributions, with implications for the marine N-cycle budget.

  18. Osteoporotic Hip Fractures: The Burden of Fixation Failure

    Directory of Open Access Journals (Sweden)

    J. M. Broderick

    2013-01-01

    Full Text Available Osteoporotic hip fractures are a major cause of morbidity and mortality in the elderly. Furthermore, reduced implant anchorage in osteoporotic bone predisposes towards fixation failure and with an ageing population, even low failure rates represent a significant challenge to healthcare systems. Fixation failure in fragility fractures of the hip ranges from 5% in peritrochanteric fractures through to 15% and 41% in undisplaced and displaced fractures of the femoral neck, respectively. Our findings, in general, support the view that failed internal fixation of these fragility fractures carries a poor prognosis: it leads to a twofold increase in the length of hospital stay and a doubling of healthcare costs. Patients are more likely to suffer a downgrade in their residential status upon discharge with a consequent increase in social dependency. Furthermore, the marked disability and reduction in quality of life evident before salvage procedures may persist at long-term followup. The risk, of course, for the elderly patient with a prolonged period of decreased functioning is that the disability becomes permanent. Despite this, however, no clear link between revision surgery and an increase in mortality has been demonstrated in the literature.

  19. Osteoporotic hip fractures: the burden of fixation failure.

    Science.gov (United States)

    Broderick, J M; Bruce-Brand, R; Stanley, E; Mulhall, K J

    2013-01-01

    Osteoporotic hip fractures are a major cause of morbidity and mortality in the elderly. Furthermore, reduced implant anchorage in osteoporotic bone predisposes towards fixation failure and with an ageing population, even low failure rates represent a significant challenge to healthcare systems. Fixation failure in fragility fractures of the hip ranges from 5% in peritrochanteric fractures through to 15% and 41% in undisplaced and displaced fractures of the femoral neck, respectively. Our findings, in general, support the view that failed internal fixation of these fragility fractures carries a poor prognosis: it leads to a twofold increase in the length of hospital stay and a doubling of healthcare costs. Patients are more likely to suffer a downgrade in their residential status upon discharge with a consequent increase in social dependency. Furthermore, the marked disability and reduction in quality of life evident before salvage procedures may persist at long-term followup. The risk, of course, for the elderly patient with a prolonged period of decreased functioning is that the disability becomes permanent. Despite this, however, no clear link between revision surgery and an increase in mortality has been demonstrated in the literature.

  20. APPLICATION OF ACETABULAR TRIDIMENSIONAL MEMORY ALLOY-FIXATION SYSTEM IN TREATMENT OF OLD ACETABULAR POSTERIOR WALL FRACTURE WITH BONE DEFECT%髋臼镍钛记忆合金三维内固定系统治疗陈旧性髋臼后壁骨折合并骨缺损

    Institute of Scientific and Technical Information of China (English)

    曹烈虎; 鲍广全; 张春才; 刘欣伟; 牛云飞; 许硕贵; 苏佳灿

    2011-01-01

    Objective To investigate the effectiveness of acetabular tridimensional memory alloy-fixation system (ATMFS) combined with autologous iliac bone in the treatment of old acetabular posterior wall fracture with bone defect. Methods Between January 2002 and February 2009, 17 patients with old acetabular posterior wall fracture and bone defect were treated, including 11 males and 6 females with an average age of 41.7 years (range, 20-60 years). The time from fracture to admission was 14-180 days (mean, 63 days). The displacement of the acetabular articular surface was more than or equal to 3 mm. According to the America Association of Orthopedic Surgeon (AAOS) acetabular fracture and defect classification standard, there were 4 cases of type I, 6 cases of type II, 5 cases of type III, and 2 cases of type IV. After the residual fracture fragments of the acetabular posterior wall and soft tissue hyperplasia were removed, the femoral head was reducted, and posterior wall defect was repaired with autologous iliac bone graft; ATMFS was used to fix acetabular posterior wall and artificial capsular ligament to reconstruct the hip so as to prevent re-dislocation of the femoral head. Results According to Matta imaging assessment standard, the results were excellent in 8 cases, good in 6 cases, fair in 2 cases, and poor in 1 case with an excellent and good rate of 82.3%. All incisions healed by first intention, and no sciatic nerve injury occurred. All patients were followed up 1-8 years (mean, 3.9 years). The mean time of fracture union was 3.6 months (range, 2-6 months). Avascular necrosis of femoral head occurred in 1 case, heterotopic ossification around the acetabulum in 1 case. According to Merle d'Aubign6-Postel scoring system evaluation, the clinical results were excellent in 9 cases, good in 6 cases, fair in 1 case, and poor in 1 case with an excellent and good rate of 88.2%. Conclusion ATMFS combined with autologous iliac bone graft and artificial ligament

  1. Pedicle screw fixation for thoracolumbar fracture with spinal cord injury:a comparison of the selective injury segment and the whole bone graft fusion%椎弓根置钉修复胸腰椎骨折合并脊髓损伤:选择性损伤节段及全部固定节段植骨融合的比较

    Institute of Scientific and Technical Information of China (English)

    史晓林; 张昊; 刘磊; 史晓东; 金晓宁; 刘清阁; 袁伟东

    2016-01-01

    BACKGROUND:Spinal canal decompression is needed in posterior pedicle screw fixation surgery for thoracolumbar burst fractures combine with spinal cord injury. The structure of posterior spine is often damaged. The posterolateral bone fusion in al fixed segment is stil the main surgery. In order to further reduce fusion segment and maintain motor unit, it is necessary to perform selective segmental bone graft fusion during fixation and decompression. OBJECTIVE: To discuss the advantages of selective posterolateral vertebral fusion for thoracolumbar fracture with spinal injury through comparing with posterolateral vertebral fusion. METHODS: Data of 83 thoracolumbar burst fracture cases, who received posterior lumbar decompression and short segment fixation with pedicle screws and bone graft through injured vertebra from January 2006 to July 2013, were analyzed retrospectively. According to fusion segments, above patients were divided into selective posterolateral vertebral fusion group (n=42) and the whole posterolateral vertebral fusion group (n=41). Perioperative index, internal fixation, vertebral height loss rate, Cobb angle, spinal nerve recovery and Oswestry Disability Index were compared between the two groups. RESULTS AND CONCLUSION:(1) Al cases were folowed up for 25-32 months. (2) There was no statistical significance in operation time, intraoperative blood loss and ambulation time between the two groups (P > 0.05). Postoperative drainage volume was less in the selective posterolateral vertebral fusion group than in the whole posterolateral vertebral fusion group (P 0.05). (4) There was no significant difference in fusion rate at 6 months after treatment between the two groups (P > 0.05). Fusion was achieved in both groups before removal of the fixator. (5) Spinal nerve recovery was found after treatment in both groups. No significant difference in Oswestry Disability Index was detected in final folow-up (P > 0.05). (6) Results verified that compared with

  2. Experimental micromechanics of the cement-bone interface.

    NARCIS (Netherlands)

    Mann, K.A.; Miller, M.A.; Cleary, R.J.; Janssen, D.; Verdonschot, N.J.J.

    2008-01-01

    Despite the widespread use of cement as a means of fixation of implants to bone, surprisingly little is known about the micromechanical behavior in terms of the local interfacial motion. In this work, we utilized digital image correlation techniques to quantify the micromechanics of the cement-bone

  3. REVERSE ENGINEERING OF THE MITKOVIC TYPE INTERNAL FIXATOR FOR LATERAL TIBIAL PLATEAU

    Directory of Open Access Journals (Sweden)

    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.

  4. Cheek drooping in 2 patients with maxillary fractures after rigid fixation with bioabsorbable mesh.

    Science.gov (United States)

    Oh, Seung Hyun; Kim, Chung Hun; Choi, Hyun Gon; Hwang, Euna

    2014-03-01

    Bioabsorbable plate-screw systems are commonly used for the internal fixation of facial bone fractures. The anterior maxilla has a unique curved shape, and fractured bony fragments tend to be small and fragile; therefore, more effective rigid fixation can be achieved using a molded bioabsorbable mesh rather than a bioabsorbable plate. Herein, we describe 2 patients with cheek drooping after a rigid fixation of comminuted maxillary fracture using bioabsorbable meshes and screws.The postoperative courses were uneventful, but both showed soft tissue bulging in the cheek area of the operation site for 12 to 13 months after the operation. No other symptom or sign related to inflammation or foreign body reaction was noted.In comminuted maxillary fractures, bone fragments are more conveniently fixed with a 1-piece molded bioabsorbable mesh. However, it is believed that a single large mesh may interfere with adhesion between the maxillary surface and the overlying soft tissue. Therefore, we recommend using the least amount of mesh to fixate maxillary bone fragments.

  5. The Clinical Usefulness of Ultrasound-Aided Fixation Using an Absorbable Plate System in Patients with Zygomatico-Maxillary Fracture

    Directory of Open Access Journals (Sweden)

    Jong Hun Lee

    2013-07-01

    Full Text Available Background  Ultrasound-aided fixation is a recently developed alternative method of treatment of zygomatico-maxillary (ZM fracture, and it can resolve the problems of excessivetorsion force and subsequent fractures of screws. We conducted this study to evaluate theclinical usefulness of ultrasound-aided fixation as compared with the conventional fixationmethod using a drill and an expanderin patientswith ZMfracture.Methods  We conducted a retrospective study in 35 patientswith ZMfracturewho had beentreated at our hospital during a period ranging fromMarch of 2008 toDecember of 2010. Wedivided them into two groups: an ultrasound-aided fixation group, comprising 13 patientswho underwent ultrasound-aided fixation (SonicWeld Rx, KLS Martin, and a conventionalgroup, comprising 22 patients who underwent conventional fixation (Biosorb FX, LinvatecBiomaterials Ltd.. We compared such variables as sex, direction, age at operation, follow-upperiod, operation duration, number of fixed holes, and time to discharge between the twogroups.Results  The ultrasound-aided fixation reduced the operation duration by about 30 minutesas comparedwith that of conventional fixation. Therewas no significant difference in followup period, number of fixed holes, ortime to discharge between the two groups. Furthermore,therewere no complicationsin either group.Conclusions  The ultrasound-aided fixation offractured ZMbone using an absorbable implantsystemissafe and effective in promptly reducing the bone fracture and providing satisfactorycosmetic outcomes overtime.

  6. Monotest in the complement fixation test: the Chorus system

    Directory of Open Access Journals (Sweden)

    Laura Meli

    2009-06-01

    Full Text Available The complement fixation test (CFT is a method used for the detection of antibodies against pathogens of infectious diseases, it has been proved to be a useful diagnostic method in the detection of acute disease in many medical laboratories.The test performed manually is time consuming and needs very skilled personnel.This study evaluates the automated Chorus CFT system with 87 serum samples in comparison with manual method using Virion-Serion reagents, against a panel of antigens, such as Adenovirus, Influenza A and B virus, Respiratory Syncythial Virus, Parainfluenza Mix, Mycoplasma Pneumoniae, and Echinococcus. The Chorus system includes standardized reagents and a monotest device to perform the single assay. In comparison to the manual CFT method, the correlation is 91.6% (7/83.The results obtained show that the automated Chorus system can be applied for detecting complement fixation antibodies against different infectious disease agents.

  7. Closed hip and long bone fractures The regimen effectiveness of antibiotic prophylaxis in surgical fixation%闭合性髋部骨折或长骨骨折围手术期抗生素预防性应用的疗效分析

    Institute of Scientific and Technical Information of China (English)

    Dan C Norvell; 王簕; 杨云峰

    2009-01-01

    对22项随机对照研究进行Meta分析,以评价在闭合性髋部骨折或长骨骨折的围手术期中,静脉预防性抗生素应用的疗效.与未应用静脉抗生素组相比,术前静脉应用抗生素(术前单剂量抗生素应用或术前联合术后多次应用)可以明显降低术后深部感染、浅表感染、泌尿道感染的发生率.当应用短效抗生素预防术中感染时,多次剂量应用可以明显降低感染的发生率.但是,当应用长效抗生素预防感染时,单剂量应用组与多剂量应用其他短效抗生素组效果相当.在比较抗生素多剂量给药疗法间或不同给药方式间(口服或静脉给药)对预防感染的疗效时发现,不论采取何种方法 ,预防感染的效果均无明显差异.%A metaanalysis of 22 randomized controlled trials found evidence to support parenteral antibiotic prophylaxis regimens for patients undergoing surgical fixation of closed hip and long bone fractures. Preoperative parenteral antibiotic doses (single or combined with multiple postoperative doses) resulted in decreased risk of deep, superficial, and urinary tract infections compared with no antibiotic. Single doses of short acting agents may be less effective than multiple doses of the same agent in decreasing the risk of any of the infections evaluated. By contrast, there was no significant difference in infection risk between a single dose of a long acting agent and multiple doses of other agents with shorter half lives. No significant differences were found when multiple dose regimens were compared or when administration routes (oral versus parenteral) were compared.

  8. Lumbar pedicle cortical bone trajectory screw

    Institute of Scientific and Technical Information of China (English)

    Song Tengfei; Wellington K Hsu; Ye Tianwen

    2014-01-01

    Objective The purpose of this study was to demonstrate the lumbar pedicle cortical bone trajectory (CBT) screw fixation technique,a new fixation technique for lumbar surgery.Data sources The data analyzed in this review are mainly from articles reported in PubMed published from 1994 to 2014.Study selection Original articles and critical reviews relevant to CBT technique and lumbar pedicle fixation were selected.Results CBT technique was firstly introduced as a new fixation method for lumbar pedicle surgery in 2009.The concepts,morphometric study,biomechanical characteristics and clinical applications of CBT technique were reviewed.The insertional point of CBT screw is located at the lateral point of the pars interarticularis,and its trajectory follows a caudocephalad path sagittally and a laterally directed path in the transverse plane.CBT technique can be used for posterior fixation during lumbar fusion procedures.This technique is a minimally invasive surgery,which affords better biomechanical stability,fixation strength and surgical safety.Therefore,CBT technique has the greatest benefit in lumbar pedicle surgery for patients with osteoporosis and obesity.Conclusion CBT technique is a better alternative option of lumbar pedicle fixation,especially for patients with osteoporosis and obesity.

  9. Backgrounds of antibiotic-loaded bone cement and prosthesis-related infection

    NARCIS (Netherlands)

    Hendriks, JGE; van Horn, [No Value; van der Mei, HC; Busscher, HJ

    2004-01-01

    Antibiotic-loaded bone cement has been in use for over 30 years for the fixation of total joint arthroplasties, although its mechanism of action is still poorly understood. This review presents the backgrounds of bone cements, prosthesis-related infection and antibiotic-loaded bone cements. It is sh

  10. Impact of bone graft harvesting techniques on bone formation and graft resorption

    DEFF Research Database (Denmark)

    Saulacic, Nikola; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    formation and graft resorption in vivo. MATERIAL AND METHODS: Four harvesting techniques were used: (i) corticocancellous blocks particulated by a bone mill; (ii) bone scraper; (iii) piezosurgery; and (iv) bone slurry collected from a filter device upon drilling. The grafts were placed into bone defects...

  11. Intramedullary foot fixation for midfoot Charcot neuroarthropathy.

    Science.gov (United States)

    Lamm, Bradley M; Siddiqui, Noman A; Nair, Ajitha K; LaPorta, Guido

    2012-01-01

    Midfoot Charcot collapse commonly occurs through the tarsometatarsal and/or midtarsal joints, which creates the characteristic "rocker bottom" deformity. Intramedullary metatarsal fixation spanning the tarsus into the talus and/or calcaneus is a recently developed method for addressing unstable midfoot Charcot deformity. The intramedullary foot fixation technique has various advantages when addressing midfoot Charcot deformity in the neuropathic patient. These advantages include anatomical realignment, minimally invasive fixation technique, formal multiple joint fusion, adjacent joint fixation beyond the level of Charcot collapse, rigid interosseus fixation, and preservation of foot length. The goals of the intramedullary foot fixation procedure are to create a stable, plantigrade, and ulcer-free foot, which allows the patient to ambulate with custom-molded orthotics and shoes.

  12. The evaluation of curative effect for lumbar spondylolisthesis by posterior lumbar intervertebral compression bone graft fusion and pedicle screw internal fixation%椎间打压植骨融合椎弓根钉内固定术治疗腰椎滑脱症疗效评价

    Institute of Scientific and Technical Information of China (English)

    黄久勤; 王传文

    2009-01-01

    Objective To investigate the curative effect for lumbar spondylolisthesis by posterior lumbar intervertebral compression bone graft fusion and pedicle screw internal fixation.Method All 39 cases with lumbar spondylolisthesis accepted treatment during January 2003 to October 2007.There were cataplasia spondylolisthesis in 14 cases and isthmic spondylolisthesis in 25 cases.Twenty-two cases had spondylolisthesis in L4 and 17 cases had spondylolisthesis in L5.According to Meyerding grading,11 patients were classified as degree Ⅰ lesion.27 patients as degree Ⅱ lesion and 1 patient as degree Ⅲ lesion.By the help of X-ray machine,pedicle screw Was embedded in the vertebral spondylolisthesis and it Was lower vertebra.Laminectomy decompress was administered in vertebral spondylolisthesis and hold-down bars was placed to open intervertebral space.Then restored the vertebral spondylolisthesis and fixed it temporary.Next,intervertebral compression bone graft fusion was finished and was adjusted.Results Follow-up period was 5 months to 4 years.Clinical outcomes were measured with Prolo evaluation scale,35 cases were cured,4 cases were good effect.Conclusions This operation has been found to be asafe,rapid and effective method for lumbar spondylolisthesis and it produces a high fusion rate and lower expense.%目的 评价椎间打压植骨融合椎弓根钉内固定术治疗腰椎滑脱症的临床疗效.方法 2003年1月至2007年10月收治的腰椎滑脱症患者39例,其中退变性滑脱14例,峡部裂性滑脱25例.L4椎体滑脱22例,L5k椎体滑脱17例.按Meyerding滑脱程度分级标准:Ⅰ度滑脱11例,Ⅱ度滑脱27例,Ⅲ度滑脱1例.C型臂X线机透视定位下在滑脱椎体及其下位椎体间植入椎弓根螺钉,行滑脱椎体全椎板减压术,安放固定棒并撑开椎间隙,进行滑脱椎体复位及临时固定,处理椎间隙,行椎间打压植骨融合术,调整钉棒进行椎间适度加压,以植骨块稳定为度.结果 本组患者

  13. Primary fixation of mini slings: a comparative biomechanical study in vivo

    Directory of Open Access Journals (Sweden)

    Paulo Palma

    2012-04-01

    Full Text Available INTRODUCTION AND OBJECTIVES: The mini sling concept for stress urinary incontinence is an anatomical approach that involves placing a midurethral low-tension tape anchored to the obturator internus muscles bilaterally. They overcome the blind passage of long needles and all the related complications. There are many different devices available and because these are outpatient procedures, primary fixation plays an important role in the outcome. The objective is to evaluate the primary fixation of the various devices of attachment of the commercially available mini-slings through biomechanical tests. MATERIALS AND METHODS: A total of 45 Wistar rats were divided in 3 groups of 15 rats each. They underwent 5 subcutaneous implantation of different mini slings and one polipropilene mesh (control, as follows: TVT-Secur® (Gynecare, USA, Type 1 polypropylene mesh (control; Ophira Mini Sling System® (Promedon, Argentina, Tissue Fixation System® (TFS PTY, Australia, Zipper Sling® and "T device" (Prosurg, USA. The abdominal wall was removed on bloc at different times after implant for biomechanical evaluation, which consisted in application of unidirectional force to the extremity of the fixation system or mesh, until it was completely removed from the tissue using a tension meter (Nexygen 3.0 Universal Testing Machine - LLOYD Instruments. The force was measured in Newtons (N. RESULTS: There was significant difference in the resistance to extraction among the different fixation systems. At 7 days the Ophira Mini Sling System® presented the best fixation and "T dispositive" the worst. CONCLUSION: Ophira mini sling System® presented the best primary fixation at 7º, 14º and 30º days. The impact of this feature in the clinical setting needs to be verified.

  14. Modeling fixation locations using spatial point processes.

    Science.gov (United States)

    Barthelmé, Simon; Trukenbrod, Hans; Engbert, Ralf; Wichmann, Felix

    2013-10-01

    Whenever eye movements are measured, a central part of the analysis has to do with where subjects fixate and why they fixated where they fixated. To a first approximation, a set of fixations can be viewed as a set of points in space; this implies that fixations are spatial data and that the analysis of fixation locations can be beneficially thought of as a spatial statistics problem. We argue that thinking of fixation locations as arising from point processes is a very fruitful framework for eye-movement data, helping turn qualitative questions into quantitative ones. We provide a tutorial introduction to some of the main ideas of the field of spatial statistics, focusing especially on spatial Poisson processes. We show how point processes help relate image properties to fixation locations. In particular we show how point processes naturally express the idea that image features' predictability for fixations may vary from one image to another. We review other methods of analysis used in the literature, show how they relate to point process theory, and argue that thinking in terms of point processes substantially extends the range of analyses that can be performed and clarify their interpretation.

  15. Determining the modulus of intact bovine vertebral cancellous bone tissue: Development and validation of a protocol

    Science.gov (United States)

    Engbretson, Andrew Craig

    Cancellous, or spongy, bone accounts for nearly 80% of the human skeleton's internal surface area, despite comprising only 20% of its mass. It is made up of a network of struts and plates that provide lightweight internal support to mammalian bones. In addition, it often serves as the main interface between the skeletal system and implanted devices such as artificial hips, knees, and fracture fixation devices. However, hip arthroplasties can succumb to loosening of the implant due to bone resorption, which is thought to be caused by a mismatch in both apparent and real stiffness between the device and the surrounding bone. Many studies have attempted to determine the Young's modulus of cancellous bone tissue, but the results are far from being in agreement. Reported values range from less than 1 to nearly 20 GPa. In addition, the small size of trabeculae has made dissection and testing a challenge. In this thesis, whole individual trabeculae from a bovine lumbar spine were tested in three-point bending to determine their Young's modulus using custom-made equipment to fit a miniature single-axis testing device. The device itself was validated by testing materials with moduli ranging from 1 to 200 GPa. The structure of the cancellous bone and the morphology of the individual struts were determined using micro x-ray computed tomography (muXCT). Individual struts were manually isolated from slices made using a low-speed saw under constant lubrication and measured under a stereomicroscope. Samples exhibiting no machined surfaces (and thus deemed to be whole, or "uncut" were compared to struts that had been cut by the saw during sectioning. Validation showed that the system was capable of determining the modulus of materials that were approximately five times stiffer than the expected cancellous modulus (copper, at 115 GPa) to within 10% of published values. This gave confidence in the results for bone. The modulus of the "uncut" specimens was found to be 15.28 2.26 GPa

  16. Treatment of infected non-unions with segmental defects with a rail fixation system.

    Science.gov (United States)

    Mudiganty, Srikanth; Daolagupu, Arup Kumar; Sipani, Arun Kumar; Das, Satyendra Kumar; Dhar, Arijit; Gogoi, Parag Jyoti

    2017-04-01

    We conducted this study to evaluate the use of rail fixation system in infected gap non-union of femur and tibia as an alternative to the established Ilizarov circular fixator technique. Prospective study. The study was done in the Department of Orthopaedic surgery in a medical school and level I trauma center to which the authors are/were affiliated. Between June 2010 and June 2015, 40 patients with infected gap non-union of femur and tibia were treated with the rail fixation system. Patients who were willing to undergo surgery and participate in the post-operative rehabilitation were included in the study. After radical debridement, the system was applied and corticotomy done. For closure of bone gap, acute docking and distraction was done in 18 cases and segmental bone transport in 22 cases. Early mobilization of patient was done along with aggressive physiotherapy. Bone and functional results were calculated according to ASAMI scoring system, and complications were classified according to Paley classification. The mean follow-up period was 22.56 months (range 8-44). Bone union with eradication of infection was achieved in all but 1 case (97.5%). Bone results were excellent in 57.5%, good 40%, fair 0% and poor in 2.5% cases, while functional result was excellent in 32.5%, good 65%, fair 0% and poor in 2.5% cases. The rail fixation system is an excellent alternative method to treat infected gap non-union of femur and tibia. It is simple, easy to use and patient-friendly.

  17. 胸腰椎结核伴重度后凸畸形:矫形内固定与植骨融合后的脊柱稳定性%Thoracolumbar tuberculosis complicated with severe kyphosis:spinal stability after orthopedic fixation and bone grafting fusion

    Institute of Scientific and Technical Information of China (English)

    邓强; 帕尔哈提·热西提; 张亚楼; 盛伟斌

    2015-01-01

    BACKGROUND:At present, there was lack of reports on the efficacy of thoracolumbar tuberculosis complicated with severe kyphosis (>90°). Choice of surgical treatment is necessary for patients with severe spinal tuberculosis kyphosis, affected heart and lung function and neurological disorders. OBJECTIVE:To retrospectively analyze the repair effect of I-stage posterior osteotomy orthopedic fixation and II-stage anterior debridement interbody bone grafting fusion in repair of patients with thoracolumbar tuberculosis complicated with severe kyphosis. METHODS:Total y 53 patients with spinal tuberculosis complicated with severe kyphosis were enrol ed. Patients underwent posterior osteotomy orthopedic fixation in the first stage, and underwent anterior debridement interbody bone grafting fusion in the second stage. X-ray, CT, MRI and other imaging examinations were conducted before and after the treatment. Erythrocyte sedimentation rate, C-reactive protein, pain visual analog scale scores, kyphosis and ASIA spinal cord injury classification before and after the treatment were compared and analyzed for clinical evaluation of efficacy. RESULTS AND CONCLUSION:Al patients had a successful surgery. The operative time was 290 (195-420) minutes, and the intra-operative amount of blood loss was 1800 (1 100-3 300) mL, the average number of fixed segments were 11.8 (9-16). Al these 53 patients were fol owed up for 26-28 months. The erythrocyte sedimentation rate and C-reactive protein of patients after treatment gradual y recovered to normal, and recovered to normal levels at the final fol ow-up. The mean correction of sagittal Cobb angle was 77.92°, the correction rate reached to 74.6%at the final fol ow-up. Til the final fol ow-up, the average loss of corrective angle was 1.35°. The lower back pain and limitation of function obtained varying degrees of al eviating after treatment. The visual analog scale scores in the final fol ow-up were significantly lower than those before

  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. Bone Markers

    Science.gov (United States)

    ... markers may be seen in conditions such as: Osteoporosis Paget disease Cancer that has spread to the bone (metastatic bone disease) Hyperparathyroidism Hyperthyroidism Osteomalacia in adults and rickets in children—lack of bone mineralization, ...

  20. Bone scan

    Science.gov (United States)

    ... legs, or spine fractures) Diagnose a bone infection (osteomyelitis) Diagnose or determine the cause of bone pain, ... 2015:chap 43. Read More Broken bone Metabolism Osteomyelitis Review Date 12/10/2015 Updated by: Jatin ...

  1. 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 ...

  2. 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 ...

  3. Intraoperative CT navigation for glenoid component fixation in reverse shoulder arthroplasty

    Directory of Open Access Journals (Sweden)

    Ashok S Gavaskar

    2013-01-01

    Full Text Available CT navigation has been shown to improve component positioning in total shoulder arthroplasty. The technique can be useful in achieving strong initial fixation of the metal backed glenoid in reverse shoulder arthroplasty. We report a 61 years male patient who underwent reverse shoulder arthroplasty for rotator cuff arthropathy. CT navigation was used intraoperatively to identify best possible glenoid bone and to maximize the depth of the fixation screws that anchor the metaglene portion of the metal backed glenoid component. Satisfactory positioning of screws and component was achieved without any perforation or iatrogenic fracture in the scapula. CT navigation can help in maximizing the purchase of the fixation screws that dictate the initial stability of the glenoid component in reverse shoulder arthroplasty. The technique can be extended to improve glenoid component position [version and tilt] with the availability of appropriate software.

  4. Prolonged Unilateral Disuse Osteopenia 14 Years Post External Fixator Removal: A Case History and Critical Review

    Directory of Open Access Journals (Sweden)

    Karen M. Knapp

    2010-01-01

    Full Text Available Disuse osteopenia is a complication of immobilisation, with reversal generally noted upon remobilisation. This case report focuses on a patient who was seen 18 years following a road traffic collision when multiple fractures were sustained. The patient had an external fixator fitted for a tibia and fibula fracture, which remained in situ for a period of 4 years. Following removal, the patient was mobilised but, still required a single crutch to aid walking. Fourteen years post removal of the fixator, the patient had a DXA scan which, demonstrated a T-score 2.5 SD lower on the affected hip. This places the patient at an increased risk of hip fracture on this side, which requires monitoring. There appear to be no current studies investigating prolonged disuse-osteopenia in patients following removal of long-term external fixators. Further research is required to quantify unilateral long-term effects to bone health and fracture risk in this population.

  5. Bone Biochemistry on the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Heer, Martina; Zwart, Sara R.

    2016-01-01

    Bone biochemical measures provide valuable insight into the nature and time course of microgravity effects on bone during space flight, where imaging technology cannot be employed. Increased bone resorption is a hallmark of space flight, while markers of bone formation are typically unchanged or decreased. Recent studies (after the deployment to ISS of the advanced resistive exercise device, ARED), have documented that astronauts with good nutritional intake (e.g., maintenance of body mass), good vitamin D status, and exercise maintained bone mineral density. These data are encouraging, but crewmembers exercising on the ARED do have alterations in bone biochemistry, specifically, bone resorption is still increased above preflight levels, but bone formation is also significantly increased. While this bone remodeling raises questions about the strength of the resulting bone, however documents beneficial effects of nutrition and exercise in counteracting bone loss of space flight.

  6. Novel anterior cruciate ligament graft fixation device reduces slippage

    OpenAIRE

    Lopez MJ; Borne A; Monroe WT; Bommala P; Kelly L.; Zhang N

    2013-01-01

    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: ...

  7. Accessory device fixation for voice rehabilitation in laryngectomised patients

    NARCIS (Netherlands)

    Hallers, Egbert Jan Olivier ten

    2006-01-01

    Summary In most patients with advanced or recurrent laryngeal or hypopharyngeal cancer, total laryngectomy is indicated. This means the loss of the three main laryngeal functions: phonation; respiration; and the prevention of aspiration during deglutition. Laryngectomy patients have various options

  8. Accessory device fixation for voice rehabilitation in laryngectomised patients

    OpenAIRE

    2006-01-01

    Summary In most patients with advanced or recurrent laryngeal or hypopharyngeal cancer, total laryngectomy is indicated. This means the loss of the three main laryngeal functions: phonation; respiration; and the prevention of aspiration during deglutition. Laryngectomy patients have various options to restore phonation such as an esophageal voice, an electrolaryngeal voice or a tracheo-esophageal voice with a shunt valve. In the latter case a silicone rubber shunt valve is placed in the trach...

  9. 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.

  10. Open reduction and internal fixation of proximal humerus fractures.

    Science.gov (United States)

    Drosdowech, Darren S; Faber, Kenneth J; Athwal, George S

    2008-10-01

    Open reduction of proximal humeral fractures has the advantage of providing direct control over each fracture fragment and permitting anatomic reduction and fixation with advanced devices. Modern fixed-angle locking plates designed specifically for proximal humerus fractures have allowed the expansion of surgical indications permitting surgeons to address more complicated fractures. Advanced preoperative imaging and fluoroscopy allow a better understanding of fracture patterns and permit the surgeon to use this knowledge intraoperatively. Research is required to further validate fracture classification systems, to develop surgical guidelines for decision making, and to compare the outcomes of the various treatments options for proximal humerus fractures.

  11. A completely intramedullary leg lengthening device

    NARCIS (Netherlands)

    Aalsma, A.M.M.; Hekman, E.E.G.; Stapert, J.W.J.L.; Grootenboer, H.J.

    1998-01-01

    The procedure and the external fixator for lengthening long bones was developed by G.A. Ilizarov in the late 1960's. This technique has, despite its proven abilities for leg lengthening and correction of angular deformities, some considerable disadvantages for patients. Discomfort, infections and re

  12. Hydroxyapatite-enhanced tibial prosthetic fixation.

    Science.gov (United States)

    Toksvig-Larsen, S; Jorn, L P; Ryd, L; Lindstrand, A

    2000-01-01

    Sixty-two knees (60 patients) were randomized to four noncemented groups. In Groups 1, 3, and 4, the bone cuts were made with a cooled saw blade. In Group 1, 15 patients were operated on with the porous coated Osteonic 7000 tibial component. In Group 2, 15 patients were operated on with the same tibial component as in Group 1 but with the use of a standard saw blade. In Group 3, 16 patients were operated on with the hydroxyapatite-coated Osteonic tibial component, and in Group 4, 16 patients were operated on with the hydroxyapatite Duracon tibial component. All patients were followed up clinically and with roentgenstereometric analysis. There were no differences among the groups regarding clinical outcome. One knee was revised (Group 2) after 1 year because of loosening of the tibial component. The maximum migration at 1 year was 1.7 mm in Group 1, 1.9 mm in Group 2, 1.3 mm in Group 3, and 1 mm in Group 4. At the 2-year followup, the migrations were 1.8 mm, 1.5 mm, 1.4 mm, and 1 mm in Groups 1, 2, 3, and 4, respectively. The inducible displacement that occurred at 1 year was 0.6 mm in Group 1, 0.5 mm in Group 2, 0.4 mm in Group 3, and 0.4 mm in Group 4. The hydroxyapatite coating had a strong positive effect on the tibial component fixation. No prosthesis in the hydroxyapatite groups showed continuous migration.

  13. Self-deploying shape memory polymer scaffolds for grafting and stabilizing complex bone defects: A mouse femoral segmental defect study.

    Science.gov (United States)

    Baker, Richard M; Tseng, Ling-Fang; Iannolo, Maria T; Oest, Megan E; Henderson, James H

    2016-01-01

    Treatment of complex bone defects places a significant burden on the US health care system. Current strategies for treatment include grafting and stabilization using internal metal plates/screws, intramedullary rods, or external fixators. Here, we introduce the use of shape memory polymer (SMP) materials for grafting and adjunct stabilization of segmental defects. Self-deploying SMP grafts and SMP sleeves capable of expanding and contracting, respectively, under intraoperative conditions were developed and evaluated in a mouse segmental defect model in vivo. Integration between grafts/sleeves and native bone was assessed using x-ray radiography, microcomputed tomography, and torsional mechanical testing. We found that SMP grafts were able to integrate with the native bone after 12 weeks, maintain defect stability, and provide torsional mechanical properties comparable to an allograft alone treatment; however no gross de novo bone formation was observed. SMP sleeves did not inhibit bony bridging at the margins, and limbs treated with a sleeve/allograft combination had torsional mechanical properties comparable to limbs treated with an allograft alone. In vitro torsional and bending tests suggest sleeves may provide additional torsional stability to defects. Incorporation of shape memory into synthetic bone graft substitutes and adjunct stabilization devices is anticipated to enhance functionality of synthetic materials employed in both applications.

  14. High-impact poly(L/D-lactide) for fracture fixation: in vitro degradation and animal pilot study.

    Science.gov (United States)

    Tams, J; Joziasse, C A; Bos, R R; Rozema, F R; Grijpma, D W; Pennings, A J

    1995-12-01

    The impact strength of amorphous lactide copolymers can be significantly improved by blending with biodegradable rubbers. Rubber toughening of amorphous poly(85L/15D -lactide) with the copolymer poly (50/50-trimethylenecarbonate-co-epsilon-caprolactone) results in a high-impact polymer (PDLLA/P(TMC-CL)). In vitro, the PDLLA/P(TMC-CL) blend retained its tensile and impact strength for a long period of time. Up to 45 weeks, the amount of water absorbed by the blend remained very low and no significant mass loss was observed. To test the suitability for fracture fixation, in a dog study mandibular fractures were fixated with PDLLA/P(TMC-CL) bone plates and screws. Bone healing was uneventful without premature failure of the implants. Although long-term degradation studies have to be carried out, PDLLA/P(TMC-CL) seems to be promising for application in fracture fixation.

  15. [Angle-fixed plate fixation or double-plate osteosynthesis in fractures of the proximal humerus: a biomechanical study].

    Science.gov (United States)

    Hessmann, Martin H; Korner, Jan; Hofmann, Alexander; Sternstein, Werner; Rommens, Pol M

    2008-06-01

    Internal fixation of fractures of the proximal humerus needs a high stability of fixation to avoid secondary loss of fixation. This is especially important in osteoporotic bone. In an experimental study, the biomechanical properties of the angle-fixed Philos plate (internal fixator) and a double-plate osteosynthesis using two one-third tubular plates were assessed. The fracture model was an unstable three-part fracture (AO type B2). Eight pairs of human cadaveric humeri were submitted to axial load and torque. In the first part of the study, it was assessed to which degree the original stiffness of the humeri could be restored after the osteotomy by the osteosynthesis procedure. Subsequently, subsidence during 200 cycles of axial loading and torque was analysed. During axial loading, the Philos plate was significantly stiffer and showed less irreversible deformation. Two double-plate fixations, but none of the Philos plate osteosynthesis, failed. During torsion, there were no significant differences between the two implants. From the biomechanical point of view, the angle-fixed Philos plate represents the implant of choice for the surgical fixation of highly unstable three-part fractures of the proximal humerus, as the internal fixator system is characterised by superior biomechanical properties.

  16. Experimental assessment of a new direct fixation implant for artificial limbs.

    NARCIS (Netherlands)

    Tomaszewski, P.K.; Lasnier, B.; Hannink, G.J.; Verkerke, G.J.; Verdonschot, N.J.J.

    2013-01-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices. offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes consid

  17. Experimental assessment of a new direct fixation implant for artificial limbs

    NARCIS (Netherlands)

    Tomaszewski, P. K.; Lasnier, B.; Hannink, G.; Verkerke, G. J.; Verdonschot, N.

    2013-01-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices, offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes consid

  18. Finite Element-Derived Surrogate Models of Locked Plate Fracture Fixation Biomechanics.

    Science.gov (United States)

    Wee, Hwabok; Reid, J Spence; Chinchilli, Vernon M; Lewis, Gregory S

    2017-03-01

    Internal fixation of bone fractures using plates and screws involves many choices-implant type, material, sizes, and geometric configuration-made by the surgeon. These decisions can be important for providing adequate stability to promote healing and prevent implant mechanical failure. The purpose of this study was to develop mathematical models of the relationships between fracture fixation construct parameters and resulting 3D biomechanics, based on parametric computer simulations. Finite element models of hundreds of different locked plate fixation constructs for midshaft diaphyseal fractures were systematically assembled using custom algorithms, and axial, torsional, and bending loadings were simulated. Multivariate regression was used to fit response surface polynomial equations relating fixation design parameters to outputs including maximum implant stresses, axial and shear strain at the fracture site, and construct stiffness. Surrogate models with as little as three regressors showed good fitting (R (2) = 0.62-0.97). Inner working length was the strongest predictor of maximum plate and screw stresses, and a variety of quadratic and interaction terms influenced resulting biomechanics. The framework presented in this study can be applied to additional types of bone fractures to provide clinicians and implant designers with clinical insight, surgical optimization, and a comprehensive mathematical description of biomechanics.

  19. Rigid internal fixation with titanium versus bioresorbable miniplates in the repair of mandibular fractures in rabbits.

    Science.gov (United States)

    Hochuli-Vieira, E; Cabrini Gabrielli, M A; Pereira-Filho, V A; Gabrielli, M F R; Padilha, J G

    2005-03-01

    The purpose of this study was to compare by qualitative histology the efficacy of rigid internal fixation with titanium system and the Lacto Sorb system in mandibular fractures in rabbits. Thirty male adult rabbits Oryctolagus cuniculus were used. Unilateral mandibular osteotomies were performed between the canine and first premolar. The animals were divided into two groups: for Group I-rigid internal fixation was performed with titanium system 1.5 mm (Synthes, Oberdorf, Switzerland), with two screws of 6 mm (bicortical) on each side of the osteotomy. For Group II-rigid internal fixation was performed with PLLA/PGA system 1.5 mm (Lacto Sorb, WLorenz, Jacksonville, FL, USA). The histological analysis evaluated the presence of inflammatory reaction, degree of bone healing and degree of resorption of the Lacto Sorb screws. The results of both fixation systems were similar, only with a small difference after 15 and 30 days. In Group I a faster bony healing was noted. But after 60 days, bony healing was similar in both groups. It is concluded that both PLLA/PGA and titanium plates and screws provide sufficient strength to permit mandibular bone healing. The resorption process of PLLA/PGA osteosynthesis material did not cause acute or chronic inflammatory reaction or foreign body reaction during the studied period.

  20. Ready to Use Tissue Construct for Military Bone & Cartilage Trauma

    Science.gov (United States)

    2014-10-01

    supplied cell- permeable green fluorescent dye (Ex/Em = 488/518 nm) and propidium iodide (PI), a cell non- permeable red fluorescent dye (Ex/Em = 488/615...fixation is commonly used for forearm bone fractures. For femur and tibia, intramedullary nailing is a common choice of internal fixation. For the...humerus, both plate and screws and intramedullary nailing are used. However, for skeletal defects following resection of malignant tumors, intramedullary

  1. Prevention of pin tract infection in external stainless steel fixator frames using electric current in a goat model

    NARCIS (Netherlands)

    van der Borden, Arnout J.; Maathuis, Patrick G. M.; Engels, Eefje; Rakhorst, Gerhard; van der Mei, Henny C.; Busscher, Henk J.; Sharma, Prashant Kumar

    2007-01-01

    Pin tract infections of external fixators used in orthopacclic reconstructive bone surgery are serious cornplications that can eventually lead to periostitis and osteomyelitis. In vitro experiments have demonstrated that bacteria adhering to stainless steel in a biotilm mode of growth detach under t

  2. 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.

  3. 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.

  4. Osseointegration: a review of the fundamentals for assuring cementless skeletal fixation

    Directory of Open Access Journals (Sweden)

    Isaacson BM

    2014-04-01

    Full Text Available Brad M Isaacson,1,2 Sujee Jeyapalina3,4 1Henry M Jackson Foundation for the Advancement of Military Medicine, 2The Center for Rehabilitation Sciences Research, Department of Physical Medicine and Rehabilitation, Uniformed Services University of Health Sciences, Bethesda, MD, USA; 3Department of Orthopedics, 4Orthopedic Research Laboratory, University of Utah, Salt Lake City, UT, USA Abstract: Direct skeletal fixation, termed osseointegration, has expanded in the last century and includes use in total joint replacements, the edentulous mandible and maxilla, and percutaneous osseointegrated prosthetics. Although it is well known that titanium and bone have the ability to form a durable bone–implant interface, new applications have emerged in the field of orthopedics, which requires a more thorough assessment of the literature. This review aims to introduce the basic biological principles for attaining osseointegration and discusses the major factors for assuring successful cementless fixation. Keywords: osseointegration, bone, skeletal attachment, total joint replacements, dental implants, percutaneous

  5. External fixation combined with limited internal fixation in the treatment of pilon tibia fractures

    Directory of Open Access Journals (Sweden)

    Golubović Zoran

    2007-01-01

    Full Text Available Background/Aim. Intraarticular fractures of the tibial plafond (pilon fractures belong to the group of most severe fractures. They are usually caused by high-energy trauma and frequently associated with a marked soft-tissue damage. Surgical treatment has replaced the traditional nonoperative treatment. The aim of this study was to present the results of the treatment of distal tibial intraarticular fracture by the use of internal fixation, as well as the combination of minimal internal fixation and external fixation. Methods. The study included 47 patients with pilon tibia fractures who went through at the Clinic for Orthopedics and Traumatology, School of Medicine, Niš (1995-2004. Within the analyzed group there were 33 (70.2% males and 14 (29.8% females. The patients mean age was 45.8 years. In the first group, which consisted of 22 patients, open reduction and internal fixation of both the tibia and the fibula was performed in the two separate incisions. The second group consisted of 25 patients managed with external fixation by external fixator "Mitković" with limited internal fixation. Besides external fixation, a minimal internal fixation was performed by the use of Kirschner wires and screws. The patients were followed-up inside a 24-months-period. Results. The obtained was a substantially high number of complications after open reduction and internal fixation in the group of patients. There was no difference in a long-term clinical outcome. Postoperative osteitis, as the most severe complication in the management of closed pilon tibia fractures, was not registered in the second group. Conclusion. Considering the results obtained in this study, it can be concluded that external fixation by the "Mitković" external fixator with the minimal internal fixation is a satisfactory method for the treatment of fractures of the tibial plafond causing less complications than internal fixation. .

  6. Volumetric analysis of corticocancellous bones using CT data

    Energy Technology Data Exchange (ETDEWEB)

    Krappinger, Dietmar; Linde, Astrid von; Rosenberger, Ralf; Blauth, Michael [Medical University Innsbruck, Department of Trauma Surgery and Sports Medicine, Innsbruck (Austria); Glodny, Bernhard; Niederwanger, Christian [Medical University Innsbruck, Department of Radiology I, Innsbruck (Austria)

    2012-05-15

    To present a method for an automated volumetric analysis of corticocancellous bones such as the superior pubic ramus using CT data and to assess the reliability of this method. Computed tomography scans of a consecutive series of 250 patients were analyzed. A Hounsfield unit (HU) thresholding-based reconstruction technique (''Vessel Tracking,'' GE Healthcare) was used. A contiguous space of cancellous bone with similar HU values between the starting and end points was automatically identified as the region of interest. The identification was based upon the density gradient to the adjacent cortical bone. The starting point was defined as the middle of the parasymphyseal corticocancellous transition zone on the axial slice showing the parasymphyseal superior pubic ramus in its maximum anteroposterior width. The end point was defined as the middle of the periarticular corticocancellous transition zone on the axial slice showing the quadrilateral plate as a thin cortical plate. The following parameters were automatically obtained on both sides: length of the center line, volume of the superior pubic ramus between the starting point and end point, minimum, maximum and mean diameter perpendicular to the center line, and mean cross-sectional area perpendicular to the center line. An automated analysis without manual adjustments was successful in 207 patients (82.8%). The center line showed a significantly greater length in female patients (67.6 mm vs 65.0 mm). The volume was greater in male patients (21.8 cm{sup 3} vs 19.4 cm{sup 3}). The intersite reliability was high with a mean difference between the left and right sides of between 0.1% (cross-sectional area) and 2.3% (volume). The method presented allows for an automated volumetric analysis of a corticocancellous bone using CT data. The method is intended to provide preoperative information for the use of intramedullary devices in fracture fixation and percutaneous cement augmentation techniques

  7. Fibula fracture stabilization with a guide wire as supplementary fixation in tibia fractures.

    Science.gov (United States)

    Dombroski, Derek; Scolaro, John A; Pulos, Nicholas; Beingessner, Daphne M; Dunbar, Robert; Mehta, Samir

    2012-05-01

    The tibia is the most commonly fractured long bone. Although the goals of fracture management are straightforward, methods for achieving anatomical alignment and stable fixation are limited. Type of management depends on fracture pattern, local soft-tissue involvement, and systemic patient factors. Tibial shaft fractures with concomitant fibula fractures, particularly those at the same level, may be difficult to manage because of their inherent instability. Typically, management of lower extremity fractures is focused on the tibia fixation, and the associated fibula fracture is managed without fixation. In this article, we describe a novel technique for intramedullary fixation of the fibula, using a humeral guide wire as an adjunct to tibia fixation in the setting of tibial shaft fracture. This technique aids in determining length, alignment, and rotation of the tibia fracture and may help support the lower extremity as whole by stabilizing the lateral column. In addition, this technique can be used to help maintain reduction of the fibula when there is concern about the soft tissues of the lower extremity secondary to swelling or injury. Our clinical case series demonstrates the safety, effectiveness, and cost-sensitivity of this technique in managing select concurrent fractures of the tibia and fibula.

  8. Bone Remodeling Monitor

    Science.gov (United States)

    Foucar, Charlie; Goldberg, Leslie; Hon, Bodin; Moore, Shannon; Williams, Evan

    2009-01-01

    The impact of bone loss due to different mechanical loadings in microgravity is a major concern for astronauts upon reintroduction to gravitational forces in exploration missions to the Moon and Mars. it has been shown that astronauts not only lose bone at differing rates, with levels up to 2% per month, but each astronaut will respond to bone loss treatments differently. Pre- and post-flight imaging techniques and frozen urine samples for post-flight laboratory immunoassays To develop a novel, non-invasive, highly . sensitive, portable, intuitive, and low-powered device to measure bone resorption levels in 'real time' to provide rapid and Individualized feedback to maximize the efficacy of bone loss countermeasures 1. Collect urine specimen and analyze the level of bone resorption marker, DPD (deoxypridinoline) excreted. 2. Antibodies specific to DPD conjugated with nanoshells and mixed with specimen, the change in absorbance from agglutination is measured by an optical device. 3. The concentration of DPD is displayed and recorded on a PDA

  9. 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

  10. 78 FR 66942 - Orthopaedic and Rehabilitation Devices Panel of the Medical Devices Advisory Committee; Notice of...

    Science.gov (United States)

    2013-11-07

    ... promote intervertebral body fusion. During the arthrodesis procedure, they are to be used with bone graft... under the heading of ``Intervertebral Fusion Device with Bone Graft, Solid-Sphere, Lumbar'',...

  11. Revision of Minimally Invasive Sacroiliac Joint Fixation: Technical Considerations and Case Studies Using Decortication and Threaded Implant Fixation

    Science.gov (United States)

    Fielding, Louis C

    2017-01-01

    Background Sacroiliac joint (SIJ) disease is increasingly recognized as a common source of low back pain. Arthrodesis of the SIJ has been shown to be clinically effective for this condition. In the last decade, minimally invasive (MI) SIJ fusion procedures have been developed to achieve the clinical effectiveness of open fusion procedures, with lower operative morbidity and faster recovery. However, SIJ fusion patients occasionally present with symptomatic nonunions necessitating revision. Methods Four patients who previously underwent MI SIJ arthrodesis returned with complaints of SIJ related pain confirmed by examination. Radiographic assessment showed lucency after fixation with triangular titanium interference implants. Loose implants were removed, and the patients were revised with a different MI SIJ fusion system that utilizes decortication, placement of autograft and graft extender, and fixation with cannulated threaded implants. The trajectory of the revision implants was in a more ventral-to-dorsal and caudal-to-cranial trajectory to place the implants perpendicularly through the articular portion of the SIJ. Results The triangular implants typically exhibited haloing lucency on radiographs and CT scans, and most were easily removed using the manufacturer’s instrumentation; only one implant was left in place as it was well-fixed. The removed implants exhibited little or no bony ongrowth. Decortication of the SIJ was performed, followed by placement of local autograft and fixation with 12.5 mm or 14.5mm diameter implants, as required. A more ventral-todorsal and caudal-to-cranial trajectory was established for the revision implants through the center of the articular region of the joint in order to maximize implant purchase in residual bone stock and achieve bony fusion through the articular portion of the SIJ. By six to twelve months post-revision, the presenting symptoms were successfully resolved in all patients. Conclusions Patients demonstrating

  12. 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

  13. Treatment of Early Post-op Wound Infection after Internal Fixation

    Science.gov (United States)

    2015-10-01

    Jefferson Davis Highway, Suite 1204, Arlington, VA 22202- 4302. Respondents should be aware that notwithstanding any other provision of law, no person shall...DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Severe fractures are...common in modern warfare with fractures being fixed via internal fixation of plates and screws to hold the fracture stable while the bone heals

  14. Comparison of the mechanical performance of different frame configurations of the Ilizarov fixator

    OpenAIRE

    Sarpel, Yaman; Gulsen, Mahir; Togrul, Emre; Capa, Mehmet; Gulmez, Turgut

    2004-01-01

    The circular frame of Ilizarov fixator could be modified due to anatomical variations and treatment aims. But these modifications in the frame system cannot always obtain the mechanical performance of the standard frame system. A standard system has two rings in each bone fragment which are connected by four longitudinal bars on each side of the ring. In this study, mechanical performance of one standard and eight modified frame systems were compared. Each system was loaded on a Material Test...

  15. Compacted cancellous bone has a spring-back effect

    DEFF Research Database (Denmark)

    Kold, S; Bechtold, JE; Ding, Ming;

    2003-01-01

    A new surgical technique, compaction, has been shown to improve implant fixation. It has been speculated that the enhanced implant fixation with compaction could be due to a spring-back effect of compacted bone. However, such an effect has yet to be shown. Therefore we investigated in a canine...... model whether implant cavities prepared with compaction had spring back. Before killing the animals, we used one of two surgical techniques to make implant cavities of identical dimensions in both lateral femoral condyles of 7 dogs. One side had the implant cavity prepared with compaction, the other....... Thus we found a spring-back effect of compacted bone, which may be important for increasing implant fixation by reducing initial gaps between the implant and bone....

  16. 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.

  17. Bone grafting simultaneous to implant placement. Presentation of a case.

    Science.gov (United States)

    Peñarrocha-Diago, Miguel; Gómez-Adrián, Maria Dolores; García-Mira, Berta; Ivorra-Sais, Mariola

    2005-01-01

    Bone defects at mandibular alveolar crest level complicate the placement of dental implants in the ideal location. Surgical reconstruction using autologous bone grafts allows implant fixation in an esthetic and functional manner. We describe a patient with large mandibular bone loss secondary to periodontal inflammatory processes. Reconstruction of the mandibular alveolar process was carried out using onlay block bone grafts harvested from the mandible. The grafts were stabilized by positioning the dental implants through them--a procedure that moreover afforded good primary implant fixation. After two years of follow-up the clinical and radiological outcome is good. In the lower jaw, where bone regeneration is complicated, we were able to achieve good results in this patient--minimizing the corresponding waiting time by grafting and placing the implants in the same surgical step.

  18. Experimental and Numerical Analysis of Screw Fixation in Anterior Cruciate Ligament Reconstruction

    Science.gov (United States)

    Chizari, Mahmoud; Wang, Bin; Snow, Martyn; Barrett, Mel

    2008-09-01

    This paper reports the results of an experimental and finite element analysis of tibial screw fixation in anterior cruciate ligament (ACL) reconstruction. The mechanical properties of the bone and tendon graft are obtained from experiments using porcine bone and bovine tendon. The results of the numerical study are compared with those from mechanical testing. Analysis shows that the model may be used to establish the optimum placement of the tunnel in anterior cruciate ligament reconstruction by predicting mechanical parameters such as stress, strain and displacement at regions in the tunnel wall.

  19. 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.

  20. Bone Metabolism on ISS Missions

    Science.gov (United States)

    Smith, S. M.; Heer, M. A.; Shackelford, L. C.; Zwart, S. R.

    2014-01-01

    Spaceflight-induced bone loss is associated with increased bone resorption (1, 2), and either unchanged or decreased rates of bone formation. Resistive exercise had been proposed as a countermeasure, and data from bed rest supported this concept (3). An interim resistive exercise device (iRED) was flown for early ISS crews. Unfortunately, the iRED provided no greater bone protection than on missions where only aerobic and muscular endurance exercises were available (4, 5). In 2008, the Advanced Resistive Exercise Device (ARED), a more robust device with much greater resistance capability, (6, 7) was launched to the ISS. Astronauts who had access to ARED, coupled with adequate energy intake and vitamin D status, returned from ISS missions with bone mineral densities virtually unchanged from preflight (7). Bone biochemical markers showed that while the resistive exercise and adequate energy consumption did not mitigate the increased bone resorption, bone formation was increased (7, 8). The typical drop in circulating parathyroid hormone did not occur in ARED crewmembers. In 2014, an updated look at the densitometry data was published. This study confirmed the initial findings with a much larger set of data. In 42 astronauts (33 male, 9 female), the bone mineral density response to flight was the same for men and women (9), and those with access to the ARED did not have the typical decrease in bone mineral density that was observed in early ISS crewmembers with access to the iRED (Figure 1) (7). Biochemical markers of bone formation and resorption responded similarly in men and women. These data are encouraging, and represent the first in-flight evidence in the history of human space flight that diet and exercise can maintain bone mineral density on long-duration missions. However, the maintenance of bone mineral density through bone remodeling, that is, increases in both resorption and formation, may yield a bone with strength characteristics different from those

  1. 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 ...

  2. Immaturity of Visual Fixations in Dyslexic Children.

    Science.gov (United States)

    Tiadi, Aimé; Gérard, Christophe-Loïc; Peyre, Hugo; Bui-Quoc, Emmanuel; Bucci, Maria Pia

    2016-01-01

    To our knowledge, behavioral studies recording visual fixations abilities in dyslexic children are scarce. The object of this article is to explore further the visual fixation ability in dyslexics compared to chronological age-matched and reading age-matched non-dyslexic children. Fifty-five dyslexic children from 7 to 14 years old, 55 chronological age-matched non-dyslexic children and 55 reading age-matched non-dyslexic children participated to this study. Eye movements from both eyes were recorded horizontally and vertically by a video-oculography system (EyeBrain(®) T2). The fixation task consisted in fixating a white-filled circle appearing in the center of the screen for 30 s. Results showed that dyslexic children produced a significantly higher number of unwanted saccades than both groups of non-dyslexic children. Moreover, the number of unwanted saccades significantly decreased with age in both groups of non-dyslexic children, but not in dyslexics. Furthermore, dyslexics made more saccades during the last 15 s of fixation period with respect to both groups of non-dyslexic children. Such poor visual fixation capability in dyslexic children could be due to impaired attention abilities, as well as to an immaturity of the cortical areas controlling the fixation system.

  3. Immaturity of Visual Fixations in Dyslexic Children.

    Directory of Open Access Journals (Sweden)

    TIADI eBi Kuyami Guy Aimé

    2016-02-01

    Full Text Available To our knowledge, behavioral studies recording visual fixations abilities in dyslexic children are scarce. The object of this paper is to explore further the visual fixation ability in dyslexics compared to chronological age-matched and reading age-matched non-dyslexic children. Fifty-five dyslexic children from 7 to 14 years old, fifty-five chronological age-matched non-dyslexic children and fifty-five reading age-matched non-dyslexic children participated to this study. Eye movements from both eyes were recorded horizontally and vertically by a video-oculography system (EyeBrain® T2. The fixation task consisted in fixating a white-filled circle appearing in the centre of the screen for 30 seconds. Results showed that dyslexic children produced a significantly higher number of unwanted saccades than both groups of non-dyslexic children. Moreover, the number of unwanted saccades significantly decreased with age in both groups of non-dyslexic children, but not in dyslexics. Furthermore, dyslexics made more saccades during the last 15 sec of fixation period with respect to both groups of non-dyslexic children. Such poor visual fixation capability in dyslexic children could be due to impaired attention abilities, as well as to an immaturity of the cortical areas controlling the fixation system.

  4. Apparatus for fixation of grinder shells upon a vibration-grinding casing

    Energy Technology Data Exchange (ETDEWEB)

    Pogosov, Yu.A.; Pugachev, V.S.

    1981-01-01

    A device is proposed for the fixation of grinder shells upon a vibration grinding table. This apparatus utilizes a table-mounting consisting of a shaft with a threaded head for a nut and lock-washer which is located in a mobile position below the locknut. Servicability is improved by utilizing radial-cantilevered protrusions in the mounting to facilitate end contact and fixation to the casing. The bushings and shaft are connected by pairs of threaded nuts while the bushings are spring-loaded relative to the table.

  5. Bone marrow aspiration

    Science.gov (United States)

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  6. Trabecular metal cup without augments for acetabular revision in case of extensive bone loss and low bone-prosthesis contact.

    Science.gov (United States)

    Pierannunzii, L; Mambretti, A; D'Imporzano, M

    2011-01-01

    Current evidences in revision hip arthroplasty suggest to treat severe acetabular bone loss with dedicated implants, such as anti-protrusio cages, stemmed cups, modular systems supplied with iliac flanges and obturatory hook. However recent literature is reporting satisfactory outcomes with simple elliptical Trabecular Metal cups. Purpose of the study was to evaluate mid-term results of such a surgical procedure. All hip revisions performed from 2008 to 2009 with implantation of a TMT multi-hole acetabular cup without augmentations were retrospectively reviewed. The cases with low-degree acetabular bone loss (stage I and II according to GIR classification), with surgical report poorly describing the bone defect, with inadequate pre- and post-operative x-rays were ruled out. Twenty-five cases were identified, but four were lost to follow-up. The twenty-one patients were 71 year-old on average (from 60 to 82), with stage IV bone loss in 6 cases and stage III bone loss in 15 cases. Mean interval from surgery to evaluation was 20.9 months (from 13 to 30). The evaluation included bone-prosthesis contact estimation, component position, survivorship, complications, final Harris Hip Score, presence of periprosthetic radiolucencies. Host bone-prosthesis contact was estimated to be about 35%. Only three implant were subsequently reoperated (for infection, early migration, recurrent dislocation). The HHS among non-reoperated 18 patients was 81.96 on average (from 63.44 to 95.82). Six cases showed thin radiolucencies in one of the three Charnley zones, while three cases showed radiolucencies in two. None of these images was evolutive, thus they were not considered signs of loosening. The mid-term results of this series confirm the hypothesis that a porous tantalum acetabular cup is an effective option to deal with difficult acetabular revisions. Although no extra-acetabular fixation device is available, the very high surface friction guaranteed by the material and the

  7. Application of Ultrasonic Devices in Management of Periodontal Lesions - Bone Response in a Case of a Tooth with Poor Treatment Prognosis

    Directory of Open Access Journals (Sweden)

    Blagova Bistra Y.

    2015-12-01

    Full Text Available BACKGROUND: Surgical treatment of odontogenic jaw cysts may include one of the following four basic methods: enucleation, marsupialization, staged combination of marsupialization and enucleation, or enucleation with curettage. Enucleation/cystectomy, alone or combined with other procedures, is the preferred choice of treatment. OBJECTIVE: The aim of the case report was to present the outcome of an ultrasound-assistant periapical cystectomy in a frontal upper tooth with indications for extraction. RESULTS: Postoperative recovery was uneventful. The functional result was satisfactory. On the follow-up X-rays a reduction of the intraosseous defect by a new bone formation could be observed. CONCLUSION: We found ultrasonic surgery to be a promising approach for safe and effective odontogenic jaw cyst removal reducing the risk of its recurrence.

  8. SURVEY SUBAXIAL CERVICAL VERTEBRAE FOR TRANSPEDICULAR SCREW FIXATION

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective In this study, the pedicles of subaxial vertebrae from C3 to C7 were measured to provide some morphometric data for cervical transpedicular screw fixation. Methods 20 dried bone cervical spinal columns (C3-C7), pedicle dimensions (pedicle height, width, length), and transverse and sagittal angles of the pedicles were performed with vernier in linear and angular measurements. Results The obtained data revealed that the mean values were approximately ranging from 6.7 to 7.2 mm for pedicle height, 4.4 to 4.9 mm for pedicle width, 22.2 to 27.7 mm for pedicle axis length, 42.3° to 51.5° for transverse angle, and 5.2° to 14.1° for sagittal angle. Conclusion Linear measurements of pedicle dimensions and also axial angles from horizontal and vertical planes may provide some anatomic limitations for subaxial cervical transpedicular screw fixation, and also contribute to the safety of the surgical procedure.

  9. Effects of gold coating on experimental implant fixation

    DEFF Research Database (Denmark)

    Zainali, Kasra; Danscher, Gorm; Jakobsen, Thomas

    2009-01-01

    -kinase activation. The present study investigated whether gilding implant Surfaces augmented early implant osseointegration and implant fixation by its modulatory effect on the local inflammatory response. Ion release was traced by autometallographic silver enhancement. Gold-coated cylindrical porous coated Ti6Al4V....... Histomorphometrical analyses showed gold-coated implants had a decrease in overall total bone-to-implant contact of 35%. Autometallographic analysis revealed few cells loaded with gold close to the gilded implant surface. The findings demonstrate that gilding of implants negatively, affects mechanical strength...... implants Were inserted press-fit in the proximal part of tibiae in nine canines and control implants without gold inserted contralateral. Observation time was 4 weeks. Biomechanical push-out tests showed that implant,,, with gold coating had decrease in mechanical strength and stiffness...

  10. Decision of the 20 april 2005 fixing the modalities of the quality control of bone densitometers devices using ionizing radiations; Decision du 20 avril 2005 fixant les modalites du controle de qualite des dispositifs d'osteodensitometrie utilisant les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-06-15

    This text defines the modalities of the quality control of bone densitometers devices using ionizing radiations. It precises the internal and external quality control operations to implement, the periodicity of the control, the criteria of the performances acceptability and what to do in case of non conformity. (A.L.B.)

  11. 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.

  12. Implants delivering bisphosphonate locally increase periprosthetic bone density in an osteoporotic sheep model. A pilot study

    Directory of Open Access Journals (Sweden)

    GVA Stadelmann

    2008-07-01

    Full Text Available It is a clinical challenge to obtain a sufficient orthopaedic implant fixation in weak osteoporotic bone. When the primary implant fixation is poor, micromotions occur at the bone-implant interface, activating osteoclasts, which leads to implant loosening. Bisphosphonate can be used to prevent the osteoclastic response, but when administered systemically its bioavailability is low and the time it takes for the drug to reach the periprosthetic bone may be a limiting factor. Recent data has shown that delivering bisphosphonate locally from the implant surface could be an interesting solution. Local bisphosphonate delivery increased periprosthetic bone density, which leads to a stronger implant fixation, as demonstrated in rats by the increased implant pullout force. The aim of the present study was to verify the positive effect on periprosthetic bone remodelling of local bisphosphonate delivery in an osteoporotic sheep model. Four implants coated with zoledronate and two control implants were inserted in the femoral condyle of ovariectomized sheep for 4 weeks. The bone at the implant surface was 50% higher in the zoledronate-group compared to control group. This effect was significant up to a distance of 400µm from the implant surface. The presented results are similar to what was observed in the osteoporotic rat model, which suggest that the concept of releasing zoledronate locally from the implant to increase the implant fixation is not species specific. The results of this trial study support the claim that local zoledronate could increase the fixation of an implant in weak bone.

  13. The Evaluation of Daily Life Activities after Application of an Osseointegrated Prosthesis Fixation in a Bilateral Transfemoral Amputee

    Science.gov (United States)

    Schalk, Stephanie A.F.; Jonkergouw, Niels; van der Meer, Fred; Swaan, Willem M.; Aschoff, Horst-H.; van der Wurff, Peter

    2015-01-01

    Abstract Individuals with a transfemoral amputation (TFA) may experience limitations in daily life due to reduced mobility and prosthesis-related problems. An osseointegrated prosthesis fixation (OPF) procedure in amputees might contribute to a solution for patients with short stumps or socket-related problems. To date, no study has specifically described the application of an OPF procedure in individuals with a TFA. This study evaluated the level of daily life activities of a 21-year old service member with a bilateral TFA and cerebral trauma. Due to a short stump length and coordination problems, an OPF procedure was deemed the most suitable option. The result of this procedure and the rehabilitation program showed an increased mobility and satisfaction as obtained by the assessment of life habits questionnaire (LIFE-H) and lower extremity functional scale. The participant was able to walk short distances and the Genium knee provided a stance position. Stair ambulation is impossible because of inadequate muscle capacity. In this specific case we conclude that the quality of life improved through the use of an OPF. However, OPF might not be the appropriate device for every individual with TFA, due to varying bone compositions, co-morbidities, and limited clinical experience and unknown long-term effects. PMID:26356693

  14. Only fixation for lumbar canal stenosis: Report of an experience with seven cases

    Directory of Open Access Journals (Sweden)

    Atul Goel

    2014-01-01

    Full Text Available Study Design and Objective: The author reports experience with treatment of degenerative lumbar canal stenosis that involved fixation-arthrodesis of the affected spinal segment using "double insurance" transarticular screws for each joint. No direct bone, ligament or disc resection is done for decompression of the spinal dural tube or root canal. Methods and Summary of Background Data: During the period March 2011-September 2011, seven patients having lumbar canal stenosis were treated with a modification of transarticular method of screw fixation that involved insertion of two or "double insurance" screws at each articular joint. The operation involved section of the spinous process at its base, opening up of the facet joint, denuding of articular cartilage, insertion of intra-articular bone graft and insertion of two transarticular screws at each facet joint. The fixation was done in four levels in two patients, at three levels in four patients and at two levels in one patient. Oswestry disability index and visual analog scale were used to clinically assess the patients before and after the surgery and at follow-up. Results: During the average period of follow-up of 26.9 months (range 24-30 months, there was varying degree of recovery of symptoms. The procedure resulted in firm stabilization and fixation of the spinal segment and provided a ground for arthrodesis. During the period of follow-up, one patient underwent re-exploration and decompressive laminectomy as she continued to have significant pain symptom. Conclusions: Vertical instability and telescoping, listhesis or overriding of the facets on physical activity seems to be the defining phenomenon in the pathogenesis of lumbar canal stenosis. The clinical outcome in our patients suggest that fixation of the spinal segment can be a rationale form of treatment. "Double insurance" transarticular method of treatment is a simple, safe, and effective method of spinal stabilization.

  15. Methanotrophy Induces Nitrogen Fixation in Boreal Mosses

    Science.gov (United States)

    Tiirola, M. A.

    2014-12-01

    Many methanotrophic bacterial groups fix nitrogen in laboratory conditions. Furthermore, nitrogen (N) is a limiting nutrient in many environments where methane concentrations are highest. Despite these facts, methane-induced N fixation has previously been overlooked, possibly due to methodological problems. To study the possible link between methanotrophy and diazotrophy in terrestrial and aquatic habitats, we measured the co-occurrence of these two processes in boreal forest, peatland and stream mosses using a stable isotope labeling approach (15 N2 and 13 CH4 double labeling) and sequencing of the nifH gene marker. N fixation associated with forest mosses was dependent on the annual N deposition, whereas methane stimulate N fixation neither in high (>3 kg N ha -1 yr -1) nor low deposition areas, which was in accordance with the nifH gene sequencing showing that forest mosses (Pleurozium schreberi and Hylocomium splendens ) carried mainly cyanobacterial N fixers. On the other extreme, in stream mosses (Fontinalis sp.) methane was actively oxidized throughout the year, whereas N fixation showed seasonal fluctuation. The co-occurrence of the two processes in single cell level was proven by co-localizing both N and methane-carbon fixation with the secondary ion mass spectrometry (SIMS) approach. Methanotrophy and diazotrophy was also studied in peatlands of different primary successional stages in the land-uplift coast of Bothnian Bay, in the Siikajoki chronosequence, where N accumulation rates in peat profiles indicate significant N fixation. Based on experimental evidence it was counted that methane-induced N fixation explained over one-third of the new N input in the younger peatland successional stages, where the highest N fixation rates and highest methane oxidation activities co-occurred in the water-submerged Sphagnum moss vegetation. The linkage between methanotrophic carbon cycling and N fixation may therefore constitute an important mechanism in the rapid

  16. Thermoplastic polymeric adhesive for structural bonding applications for orthopaedic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devanathan, D.; King, R.; Swarts, D.; Lin, S. [Zimmer, Inc., Warsaw, IN (United States); Ramani, K.; Tagle, J. [Purdue Univ., West Lafayette, IN (United States). Dept. of Mechanical Engineering

    1994-12-31

    The orthopaedics industry has witnessed tremendous growth in recent years primarily due to the introduction of high performance, porous coated implants. These devices have eliminated the need for the use of bone cement for in vivo implant fixation, replacing it with the ingrowth of bone into the porous surfaces. The metallurgical bonding processes used for attaching the porous to the implant body introduce some undesirable effect i.e., the reduction of the fatigue strength of the implant due to the ``notches`` created and also due to the high temperature exposure during the sintering operations. This paper describes the development of a thermoplastic polymeric adhesive based structural bonding technique. The high performance polymeric adhesive is fully characterized with respect to its intended application. The design of the porous layer is optimized to achieve a reliable bond to the implant. A thermal heating/cooling process was developed to control the final polymer morphology. Static and fatigue tests were conducted to fully characterize the adhesive bond strength. A ring shear test method was developed to determine the shear strength of the bond interface. Besides the characterization of the adhesive bond, the joints will be analyzed using finite element models. The correlation between the analytical models and the

  17. Effect of insulating layer material on RF-induced heating for external fixation system in 1.5 T MRI system.

    Science.gov (United States)

    Liu, Yan; Kainz, Wolfgang; Qian, Songsong; Wu, Wen; Chen, Ji

    2014-09-01

    The radio frequency (RF)-induced heating is a major concern when patients with medical devices are placed inside a magnetic resonance imaging (MRI) system. In this article, numerical studies are applied to investigate the potentials of using insulated materials to reduce the RF heating for external fixation devices. It is found that by changing the dielectric constant of the insulation material, the RF-induced heating at the tips of devices can be altered. This study indicates a potential technique of developing external fixation device with low MRI RF heating.

  18. Nitrogen Fixation in Denitrified Marine Waters

    OpenAIRE

    Camila Fernandez; Laura Farías; Osvaldo Ulloa

    2011-01-01

    Nitrogen fixation is an essential process that biologically transforms atmospheric dinitrogen gas to ammonia, therefore compensating for nitrogen losses occurring via denitrification and anammox. Currently, inputs and losses of nitrogen to the ocean resulting from these processes are thought to be spatially separated: nitrogen fixation takes place primarily in open ocean environments (mainly through diazotrophic cyanobacteria), whereas nitrogen losses occur in oxygen-depleted intermediate wat...

  19. Prediction of bone density around orthopedic implants delivering bisphosphonate.

    Science.gov (United States)

    Stadelmann, Vincent A; Terrier, Alexandre; Gauthier, O; Bouler, J-M; Pioletti, Dominique P

    2009-06-19

    The fixation of an orthopedic implant depends strongly upon its initial stability. Peri-implant bone may resorb shortly after the surgery. This resorption is directly followed by new bone formation and implants fixation strengthening, the so-called secondary fixation. If the initial stability is not reached, the resorption continues and the implant fixation weakens, which leads to implant loosening. Studies with rats and dogs have shown that a solution to prevent peri-implant resorption is to deliver bisphosphonate from the implant surface. The aims of the study were, first, to develop a model of bone remodeling around an implant delivering bisphosphonate, second, to predict the bisphosphonate dose that would induce the maximal peri-implant bone density, and third to verify in vivo that peri-implant bone density is maximal with the calculated dose. The model consists of a bone remodeling equation and a drug diffusion equation. The change in bone density is driven by a mechanical stimulus and a drug stimulus. The drug stimulus function and the other numerical parameters were identified from experimental data. The model predicted that a dose of 0.3 microg of zoledronate on the implant would induce a maximal bone density. Implants with 0.3 microg of zoledronate were then implanted in rat femurs for 3, 6 and 9 weeks. We measured that peri-implant bone density was 4% greater with the calculated dose compared to the dose empirically described as best. The approach presented in this paper could be used in the design and analysis processes of experiments in local delivery of drug such as bisphosphonate.

  20. 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.

  1. 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.

  2. Variable Nitrogen Fixation in Wild Populus.

    Directory of Open Access Journals (Sweden)

    Sharon L Doty

    Full Text Available The microbiome of plants is diverse, and like that of animals, is important for overall health and nutrient acquisition. In legumes and actinorhizal plants, a portion of essential nitrogen (N is obtained through symbiosis with nodule-inhabiting, N2-fixing microorganisms. However, a variety of non-nodulating plant species can also thrive in natural, low-N settings. Some of these species may rely on endophytes, microorganisms that live within plants, to fix N2 gas into usable forms. Here we report the first direct evidence of N2 fixation in the early successional wild tree, Populus trichocarpa, a non-leguminous tree, from its native riparian habitat. In order to measure N2 fixation, surface-sterilized cuttings of wild poplar were assayed using both 15N2 incorporation and the commonly used acetylene reduction assay. The 15N label was incorporated at high levels in a subset of cuttings, suggesting a high level of N-fixation. Similarly, acetylene was reduced to ethylene in some samples. The microbiota of the cuttings was highly variable, both in numbers of cultured bacteria and in genetic diversity. Our results indicated that associative N2-fixation occurred within wild poplar and that a non-uniformity in the distribution of endophytic bacteria may explain the variability in N-fixation activity. These results point to the need for molecular studies to decipher the required microbial consortia and conditions for effective endophytic N2-fixation in trees.

  3. External fixation in the treatment of open tibial shaft fractures

    Directory of Open Access Journals (Sweden)

    Golubović Zoran

    2008-01-01

    Full Text Available Background/Aim. Besides the conquasant fractures, open tibia shaft fractures belong to the group of the most severe fractures of tibia. Open tibia shaft fracture is one of the most common open fractures of long bones. They most frequently occur as a result of traffic accidents caused by the influence of a strong direct force. Methods. Within the period from January, 2000 to December 31, 2005. at the Clinic for Orthopaedics and Traumatology, Clinical Center Nis, 107 patients with open tibial fractures were treated. We analyzed 96 patients with open tibial fracture. In the series analyzed, the male sex was prevalent - there were 74 men (77.08%. The mean age was 47.3 years. The youngest patient was 17 years old, while the oldest patient was 79. According to the classification of the Gustilo et al. in the analysed group there were 30 (31.25% open tibial fractures of the I degree, 31 (32.29% of the II degree, 25 (26.05% of the III A degree, 8 (8.33% of the III B degree and 2 (2.08% of the III C degree. In 95 of the patients the treatment of open tibia shaft fractures consisted of the surgical treatment of wound and the external fixation of the fractured bone using "Mitkovic" type external fixator with a convergent method of pin applications. One primary amputations had been done in patients with grade IIIC open tibial fracture with large soft tissue defect. Results. Of the 96 open tibial fractures available for follow-up, 73 (76.04% healed without severe complications (osteitis, pseudoarthrosis, valgus malunion and amputation. Ther were nine (9.38% soft tissue pin track infections and six (6.25% superficial wound infections. The mean time of union was 21 (14-36 week. Among severe local complications associated with open tibial fractures, in eight patients (8.33% was registered osteitis, and in nine patients (9.38% fracture nonunion and the development of pseudoarthrosis. Three of the patients (3.13% had more than 10 degree valgus malunion. In one

  4. Assessment of external fixator reusability using load- and cycle-dependent tests.

    Science.gov (United States)

    Matsuura, Maiko; Lounici, Smain; Inoue, Nozomu; Walulik, Stephen; Chao, Edmund Y S

    2003-01-01

    No standard method has been established for investigating repeated use of an external fixator. The purpose of the current study was to establish a fatigue testing method for assessing fixator frame reuse. A unilateral DynaFix trade mark external fixator system was tested using high-load and low-cycle (900-150 N at 5 Hz) and low-load and high-cycle (450-100 N at 10 Hz) tests (assumed one use of 500,000 and 1 million cycles, respectively). These loading conditions were selected to simulate single clinical use and to satisfy Food and Drug Administration requirements. In the high-load low-cycle test, substantial failure of the serrated joint occurred before completion of the first simulated use. In the low-load high-cycle test, all fixators completed three simulated clinical uses without failure, although (1/4) of the serrated joint components had hairline cracks. The high-load low-cycle test identified the fixator components which should be examined and replaced if reuse of the fixator is to be considered. Wear and deformation of the set screw on the rotary joint and telescoping mechanisms were observed in the low-load high-cycle test but not in the high-load low-cycle test. Therefore, if the unilateral DynaFix trade mark fixators are being considered for reusability, the number of reuses should be limited as the whole structure of the device will experience fatigue damage as the loading cycle increases.

  5. A STUDY OF FUNCTIONAL AND RADIOLOGICAL OUTCOME OF UNDISPLACED SCAPHOID FRACTURES TREATED WITH PERCUTANEOUS HEADLESS SCREW FIXATION

    Directory of Open Access Journals (Sweden)

    Tarigopula

    2016-04-01

    Full Text Available BACKGROUND Scaphoid is the most commonly fractured carpal bone, accounting for approximately 60% of all carpal fractures. This injury is commonly seen in active young adults after a fall on an outstretched hand. Management of scaphoid fractures is controversial. Displaced scaphoid fractures are associated with risk of non-union and osteonecrosis. Surgical fixation is recommended for displaced scaphoid fractures of proximal pole, fractures with delayed treatment or diagnosis and non-union. Open reduction and internal fixation of acute scaphoid fractures has been reported to give good results in several nonrandomised, retrospective studies. The incidence of complications after operative treatment of non-displaced fractures has decreased with the advent of safer, more reliable implants and percutaneous techniques. CONCLUSION Percutaneous headless screw fixation is a well-documented surgical procedure. Undisplaced scaphoid fractures fixed by percutaneous headless screw fixation yield better results than patients treated conservatively. Good range of motion is achieved after fixation. It relieves pain and functional disability experienced by patients. Patients achieve good range of motion. Trabecular continuity is achieved in most of the patients before 8 weeks. Most of the patients had resumed normal daily activities before 3 months. This study suggests that percutaneous headless screw fixation for undisplaced scaphoid fractures provides satisfactory clinical and radiographic outcomes after an intermediate duration follow-up. Even though the procedure is not free of complications, the overall functional and clinical outcome had shown good results.

  6. Fixação esquelética externa tipo Ia (unilateral-uniplanar para osteossíntese diafisária de úmero em pombos domésticos (Columba livia Type Ia (unilateral-uniplanar external Skeletal fixation for treatment of humeral diaphysis fracture in domestic pigeons (Columba livia

    Directory of Open Access Journals (Sweden)

    Alessandro Moraes Leotte

    2004-12-01

    Full Text Available Das várias patologias que podem acometer as aves, são mais freqüentes as fraturas de ossos longos das asas e dos membros pélvicos. Este experimento teve como objetivo observar, por meio de exames clínicos, histológicos e radiográficos, a resposta cicatricial óssea ao uso do fixador externo tipo Ia (unilateral-uniplanar na redução aberta de fratura diafisária, de úmero em pombos domésticos (Columba livia. Foram estudados 14 pombos com peso variando entre 290 e 420 gramas. A fratura foi realizada na diáfise do úmero direito e, logo após, estabilizada com aparelho de fixação externa tipo Ia, utilizando-se, como barra de fixação, o acrílico autopolimerizável. O tempo médio para o completo desaparecimento da linha de fratura foi de 28±6,44 dias e para formação de calo ósseo, 17±3,26 dias. As aves, mesmo com o aparelho de fixação, retornaram ao vôo aos 28±1,2 dias, exceto uma que não recuperou a capacidade de vôo. A técnica de fixação externa demonstrou ser eficaz para o tratamento de fraturas diafisárias de úmero em pombos domésticos.Among the various pathologies that can inflict birds, the long bones fractures of the wings, and pelvic members are more commom. Fourteeen domestic pigeons (Columba livia weighing 290 to 420g, were submitted to open reduction of humeral diaphysis fracture with external fixator type Ia (unilateral-uniplanar in order to evaluate the clinical, histological and radiographic evolution of the bone healing. The external fixator device was stabilized with methilmetacrylate acrylic. The average time necessary to the complete disappearance of the fracture line by radiographic evaluation was 28±6.44 days. The bone callus was identified at 17±3.26 postoperative days. The birds returned to flying in 28±1.2 days yet with the fixation device and only one did not recovere the flying abillity. The external fixation technique is an efficient method to treat diaphiseal humeral fracture in domestic

  7. Step-by-step external fixation of unstable pelvis with separate anterior and posterior modules

    Institute of Scientific and Technical Information of China (English)

    Ivan Viktorovich Borozda; Nikolay Alexandrovich Ganzhurov; Alexander Alexandrovich Kapustyansky; Roman Valerievich Nikolaev; Kirill Sergeevich Golokhvast

    2016-01-01

    Objective: To evaluate the treatment outcomes of patients with pelvic ring injury by applying step-by-step external pelvic fixation and circular external fixation device.Methods: A total of 28 patients suffering from disintegrated pelvic ring injury are involved in the study. Fourteen patients(the treatment group) underwent step-by-step external pelvic fixation by applying anterior(anti-shock) and posterior modules. For the rest 14 patients(the experimental group), the osteosynthesis were conducted by means of a circular external fixation device. The long-term outcomes were evaluated in a year after the injury.Results: The residual deformity of 5(4–7) mm was observed in 10 patients(71.4%) from the experimental group. In the treatment group, the residual deformity was evident only in 4(28.6%) cases being 2.5(2–3) mm(P = 0.000 319) on the average. The functional result(according to the Majeed scale) was statistically better in the treatment group(P = 0.000 319). Nine(64.3%) and five(35.7%) patients in treatment group showed excellent and positive results, respectively. The excellent result was demonstrated by 3patients(21.4%) of the experimental group, the positive outcomes were observed in 6 cases(42.9%) and the unsatisfactory one was displayed by 1 patient(7.1%) of the same group.Conclusions: The modular approach applied is the advantage of the transosseous osteosynthesis allowing for a separate anterior(anti-shock) fixation and final posterior reposition of the pelvic ring preceded by the stabilization of vital functions. The above mentioned method gives an opportunity to increase the amount of techniques applied for the pelvic external fixation in polytrauma cases.

  8. 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.

  9. Use of self-tapping metal screws for temporary fixation of a resorbable plate system in maxillofacial surgery.

    Science.gov (United States)

    Iwai, Toshinori; Omura, Susumu; Aoki, Noriaki; Tohnai, Iwai

    2015-05-01

    Resorbable plate systems have been used in maxillofacial surgery to obviate the need for plate removal. However, resorbable plates and screws are very costly, and refixation with additional screws may be necessary when reduction or repositioning of the bone segment is inaccurate. Here we report the use of self-tapping metal screws for temporary fixation of a resorbable plating system in maxillofacial surgery to avoid the use of additional screws following inaccurate fixation or the reuse of resorbable screws, which may result in loosening.

  10. Replacement, refinement, and reduction: necessity of standardization and computational models for long bone fracture repair in animals.

    Science.gov (United States)

    Reifenrath, Janin; Angrisani, Nina; Lalk, Mareike; Besdo, Silke

    2014-08-01

    In the field of fracture healing it is essential to know the impacts of new materials. Fracture healing of long bones is studied in various animal models and extrapolated for use in humans, although there are differences between the micro- and macrostructure of human versus animal bone. Unfortunately, recommended standardized models for fracture repair studies do not exist. Many different study designs with various animal models are used. Concerning the general principles of replacement, refinement and reduction in animal experiments (three "Rs"), a standardization would be desirable to facilitate better comparisons between different studies. In addition, standardized methods allow better prediction of bone healing properties and implant requirements with computational models. In this review, the principles of bone fracture healing and differences between osteotomy and artificial fracture models as well as influences of fixation devices are summarized. Fundamental considerations regarding animal model choice are discussed, as it is very important to know the limitations of the chosen model. In addition, a compendium of common animal models is assembled with special focus on rats, rabbits, and sheep as most common fracture models. Fracture healing simulation is a basic tool in reducing the number of experimental animals, so its progress is also presented here. In particular, simulation of different animal models is presented. In conclusion, a standardized fracture model is of utmost importance for the best adaption of simulation to experimental setups and comparison between different studies. One of the basic goals should be to reach a consensus for standardized fracture models.

  11. Effect of Different Distal Fixation Augmentation Methods on the Pullout Strength of Fassier-Duval Telescoping Rods.

    Science.gov (United States)

    Mansour, Alfred; Barsi, James; Baldini, Todd; Georgopoulos, Gaia

    2016-01-01

    Antegrade telescoping rods have been introduced for use in pediatric patients with osteogenesis imperfecta (OI) to decrease the incidence of long-bone fractures and to correct and prevent deformities. Recent studies have documented failures of telescoping intramedullary rods due to inadequate distal fixation. The purpose of this study was to evaluate the pullout strength of distal fixation of the telescoping rod with and without synthetic calcium phosphate or polymethylmethacrylate (PMMA) augmentation. Four sets of 6 telescoping distal fixation rods were fixed according to standard insertion technique into an open-cell rigid-foam synthetic bone block simulating OI bone. The groups tested were as follows: control (no augmentation), 0.75 mL of PMMA-augmented, 0.75 mL of PMMA-rescued (stripped distal fixation, then resecured after PMMA augmentation), and 0.75 mL of bioabsorbable-calcium phosphate (CP)-augmented. All rods were tested to failure. The peak load was recorded. Average pullout strengths were as follows: control, 20±6.6 N; PMMA, 125±16.8 N; PMMA-rescued, 137±11.9 N; bioabsorbable-CP, 81±10.3 N. All augmented groups had significantly higher pullout strength compared with the control (P<.001). The PMMA and PMMA-rescued groups failed at the PMMA/bone interface, whereas the bioabsorbable-CP group failed at the cement/rod interface. All augmented constructs improved pullout strength by at least 400% compared with the control. Bioabsorbable cement may be less detrimental to the physis if pullout still occurs despite augmentation due to its mode of failure. This study provides biomechanical evidence to support the further in vivo investigation of either PMMA or bioabsorbable cement augmentation to improve pullout strength of distal telescoping rod fixation.

  12. 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

  13. INTRA MEDULLARY FIXATION OF SUB TROCHANTERIC FRACTURERS WITH LONG PROXIMAL FEMORAL NAIL & STAINLESS STEEL WIRE FIXATION: A STUDY

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    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

  14. Design of the device applying pulsed electromagnetic field in bone cell culture%脉冲电磁场辅助骨细胞培养装置的研制

    Institute of Scientific and Technical Information of China (English)

    谢小波; 庞丽云; 崔红岩; 李小红; 屈承端; 陈先农; 胡勇

    2008-01-01

    Objective A pulsed electromagnetic fields(PEMF) device with adjustable parameters designed for bone cell culture was designed according to the principle of pulsed electromagnetic fields as an effective physical factor to regulate the growth of bone cells. Functions of hardware and software were introduced as well as the design of the stimulating board. Method Based on previous research result, the device was designed to generate electromag- netic pulse with intensity of 4-6 mT and frequency of 8 Hz. The stimulating board was designed according to the size of cell culture plate. Up to six plates are allowed to be placed on the board simultaneously. Magnetic material was in- troduced to assure the uniform magnetic field. Results Functions of the device were tested and designed parameters were proved to be accomplished. The electromagnetic field generated on the surface of the stimulating board was uni- form. Conclusion All parameters designed are accomplished and the magnetic field detected on the surface of the board is uniform and ready be used as a physical factor in the up-coming experiment of bone cell culture.%目的 根据脉冲电磁场对骨细胞的作用机制,设计了能够产生均匀磁场、参数可调的脉冲电磁场发生装置和磁场作用板;叙述了实验装置的硬件构成、软件控制功能以及磁场作用板的设计,并通过试验测试,观察记录了在未加入磁性材料和加入磁性材料后磁场的分布情况.方法 设计了强度为4~6 mT、频率8 Hz的参数可调的脉冲电磁场发生装置和专用的适合细胞培养的磁场作用装置,并对产生的磁场进行了实验测定.结果 实验装置运行时,对各参数检测表明,实验装置满足设计的要求:在加入磁性材料后,磁场作用表面的磁场分布均匀.结论 实验装置满足设计要求,可为进一步进行骨细胞培养提供可靠的实验手段.

  15. 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.

  16. Extraosseous radiotracer uptake on bone scan in beta-thalassemia: report of one case; Fixation extraosseuse du radiotraceur lors de la realisation d'une scintigraphie du squelette chez un patient atteint de beta-thalassemie: a propos d'un cas

    Energy Technology Data Exchange (ETDEWEB)

    Guezguez, M.; Nouira, M.; Sfar, R.; Chatti, K.; Ben Fradj, M.; Ben Ali, K.; Ajmi, S.; Essabbah, H. [CHU Sahloul, Service de Medecine Nucleaire, Sousse (Tunisia); Zrour, S. [EPS F. Bourguiba, Service de Rhumatologie, Monastir (Tunisia)

    2009-10-15

    Red blood cell transfusion, main therapeutic modality of beta-thalassemia, leads to iron overload which may perturb several metabolic ways. The aim of this paper is to illustrate the uptake abnormalities observed on bone scan of thalassaemic patients and to discuss mechanisms of extraosseous accumulation of the radiopharmaceutical in this pathology. We report a 16-year-old child suffering from beta-thalassemia major undergoing transfusion therapy. A bone scan was indicated to look for osseous infection. This study revealed a little skeletal uptake and abnormal liver, splenic and renal accumulation. A repeat bone scan, performed three weeks later showed a better skeletal uptake which enabled the discovery of focal abnormalities and made the diagnostic easier. The effect of iron overload on radiopharmaceuticals uptake in bone scan is known since 1975. Dissociation of {sup 99m}Tc from the carrier ligand due to the presence of iron excess seems the most plausible hypothesis. Free {sup 99m}Tc can be bound to other tissular substrates which can explain extraosseous uptake. The normally available pool for bone is reduced and then the skeletal uptake decreased. This report limits considerably the sensitivity of the bone scan. A well-led iron chelation and eventually the use of diuretic drug may guarantee a better quality of bone scan images. (authors)

  17. 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

  18. 颈前路减压零切迹椎间植骨融合内固定系统治疗颈椎病的早期疗效分析%Early outcome of anterior cervical discectomy and fusion using a Zero-profile interbody fusion and fixation device for cervical spondylosis

    Institute of Scientific and Technical Information of China (English)

    缪锦浩; 匡勇; 陈德玉; 杨立利; 王新伟; 陈宇; 刘晓伟

    2012-01-01

    目的:分析颈前路减压零切迹椎间植骨融合内固定系统(Zero-P)治疗颈椎病的早期疗效.方法:2010年6月~10月39例颈椎病患者接受颈前路减压Zero-P植骨内固定手术,患者年龄33~71岁,平均50.3岁.神经根型颈椎病8例,脊髓型31例;单间隙14例,2个间隙18例,3个间隙7例.共置入Zero-P 71枚,C3/4、C4/5、C5/6、C6/7椎间隙置入Zero-P分别为8、19、30、14枚.术前、术后2个月及12个月对神经根型颈椎病患者行VAS评分、脊髓型颈椎病患者行JOA评分,在颈椎中立侧位X线片上测量颈椎Cobb角(C2和C7椎体后缘切线的夹角),观察术后吞咽不适的发生率以及症状持续时间.根据术后伸屈侧位X线片观察手术间隙有无异常活动.结果:手术时间48~130min,平均86min:术中出血量40~310ml,平均110ml.14例患者术后1周内出现吞咽不适,其中13例术后2个月内症状消失,1例(2.6%)症状持续至术后4个月消失.随访12~16个月,平均14.6个月.神经根型颈椎病患者术后2个月、12个月时的VAS评分分别为1.5士0.8分、1.3±09分,均低于术前的7.3+1.3分(P<0.05).脊髓型颈椎病患者术后2个月、12个月时的JOA评分分别为14.6±1.1分、15.0±1.2分,均高于术前的9.7±1.7分(P<0.05).术后2个月及12个月颈椎Cobb角分别为18.4°士9.6°、17.8°±9.2°,大于术前的9.0°±10.0°(P<0.05).术后12个月时的VAS评分、JOA评分和颈椎Cobb角与术后2个月比较无显著性差异(P>0.05).随访期间手术间隙无异常活动,内置物无移位.结论:颈前路减压Zero-P植骨内固定治疗颈椎病的早期疗效满意,稳定性可靠,可重建颈椎曲度,术后慢性吞咽不适发生率低.%Objectives: To analyze the early outcome of anterior cervical discectomy and fusion(ACDF) using a Zero-profile interbody fusion and fixation device (Zero-P) for interbody fusion in the treatment of cervical spondylosis. Methods: The study enrolled thirty-nine patients who

  19. GMP-compliant isolation and expansion of bone marrow-derived MSCs in the closed, automated device quantum cell expansion system.

    Science.gov (United States)

    Rojewski, Markus T; Fekete, Natalie; Baila, Stefano; Nguyen, Kim; Fürst, Daniel; Antwiler, Delbert; Dausend, Julia; Kreja, Ludwika; Ignatius, Anita; Sensebé, Luc; Schrezenmeier, Hubert

    2013-01-01

    The estimated frequency of MSCs in BM is about 0.001-0.01% of total nucleated cells. Most commonly, one applied therapeutic cell dose is about 1-5 million MSCs/kg body weight, necessitating a reliable, fast, and safe expansion system. The limited availability of MSCs demands for an extensive ex vivo amplification step to accumulate sufficient cell numbers. Human platelet lysate (PL) has proven to be a safe and feasible alternative to animal-derived serum as supplement for MSC cultivation. We have investigated the functionally closed automated cell culture hollow fiber bioreactor Quantum cell expansion system as an alternative novel tool to conventional tissue flasks for efficient clinical-scale MSC isolation and expansion from bone marrow using PL. Cells expanded in the Quantum system fulfilled MSC criteria as shown by flow cytometry and adipogenic, chondrogenic, and osteogenic differentiation capacity. Cell surface expression of a variety of chemokine receptors, adhesion molecules, and additional MSC markers was monitored for several passages by flow cytometry. The levels of critical media components like glucose and lactate were analyzed. PDGF-AA, PDGF-AB/BB, bFGF, TGF-β1, sICAM-1, sVCAM-1, RANTES, GRO, VEGF, sCD40L, and IL-6 were assessed using a LUMINEX platform. Originally optimized for the use of fetal calf serum (FCS) as supplement and fibronectin as coating reagent, we succeeded to obtain an average of more than 100×10(6) of MSCs from as little as 18.8-28.6 ml of BM aspirate using PL. We obtained similar yields of MSCs/µl BM in the FCS-containing and the xenogen-free expansion system. The Quantum system reliably produces a cellular therapeutic dose in a functionally closed system that requires minimal manipulation. Both isolation and expansion are possible using FCS or PL as supplement. Coating of the hollow fibers of the bioreactor is mandatory when loading MSCs. Fibronectin, PL, and human plasma may serve as coating reagents.

  20. Caspar plate fixation for the treatment of complex hangman's fractures.

    Science.gov (United States)

    Tuite, G F; Papadopoulos, S M; Sonntag, V K

    1992-05-01

    This report details our recent experience with the surgical treatment of complex hangman's fractures after failure of closed reduction and immobilization in external orthosis. We have successfully treated hangman's fractures in 5 patients with anterior Caspar plate stabilization and C2-C3 interbody fusion. The specific anatomical features of these fractures were complex, rendering the spines of the patients highly unstable. The patients were considered surgical candidates when reduction could not be achieved or maintained with axial traction or halo immobilization. Each patient underwent anterior C2-C3 interbody bone fusion and Caspar plating from C2 to C3. All patients achieved adequate intraoperative reduction and were immobilized postoperatively with a halo vest. The follow-up period ranged from 3 to 28 months and provided a 100% fusion rate with no complications related to plating or nonunion. Our initial experience indicates that anterior C2-C3 interbody bone fusion and Caspar plate fixation is a suitable treatment option for patients with complex hangman's fractures who are not successfully managed nonoperatively.

  1. Evaluation of an intramedullary bone stabilization system using a light-curable monomer in sheep.

    Science.gov (United States)

    Zani, Brett G; Baird, Rose; Stanley, James R L; Markham, Peter M; Wilke, Markus; Zeiter, Stephan; Beck, Aswin; Nehrbass, Dirk; Kopia, Gregory A; Edelman, Elazer R; Rabiner, Robert

    2016-02-01

    Percutaneous intramedullary fixation may provide an ideal method for stabilization of bone fractures, while avoiding the need for large tissue dissections. Tibiae in 18 sheep were treated with an intramedullary photodynamic bone stabilization system (PBSS) that comprised a polyethylene terephthalate (Dacron) balloon filled with a monomer, cured with visible light in situ, and then harvested at 30, 90, or 180 days. In additional 40 sheep, a midshaft tibial osteotomy was performed and stabilized with external fixators or external fixators combined with the PBSS and evaluated at 8, 12, and 26 weeks. Healing and biocompatibility were evaluated by radiographic analysis, micro-computed tomography, and histopathology. In nonfractured sheep tibiae, PBSS implants conformably filled the medullary canal, while active cortical bone remodeling and apposition of new periosteal and/or endosteal bone was observed with no significant macroscopic or microscopic observations. Fractured sheep tibiae exhibited increased bone formation inside the osteotomy gap, with no significant difference when fixation was augmented by PBSS implants. Periosteal callus size gradually decreased over time and was similar in both treatment groups. No inhibition of endosteal bone remodeling or vascularization was observed with PBSS implants. Intramedullary application of a light-curable PBSS is a biocompatible, feasible method for fracture fixation.

  2. The Influence of Partial Knee Replacement Designs on Tensile Strain at Implant-Bone Interface

    Directory of Open Access Journals (Sweden)

    He Wang

    2012-01-01

    Full Text Available Partial knee replacement (PKR results in fast recovery and good knee mechanics and is ideal to treat medial knee osteoarthritis. Cementless PKR depends on bone growing into the implant surface for long-term fixation. Implant loosening may occur due to high tensile strain resulted from large mechanical loads during rehab exercises. The purpose of this study is to investigate whether external fixations such as superior screw and frontal flange could reduce the tensile strain at the implant-bone interface. Three medial PKRs were designed. The first PKR had no external fixations. A superior screw and a frontal flange were then added to the first PKR to form the second and third PKR designs, respectively. Finite element analysis was performed to examine the tensile strain at the implant-bone interface during weight-bearing exercises. The PKR with no external fixations exhibited high tensile strain at the anterior implant-bone interface. Both the screwed and flanged PKRs effectively reduced the tensile strain at the anterior implant-bone interface. Furthermore, the flanged PKR resulted in a more uniform reduction of the tensile strain than the screwed PKR. In conclusion, external fixations are necessary to alleviate tensile strain at the implant-bone interface during knee rehab exercises.

  3. Arthroscopic double-row suture anchor fixation of minimally displaced greater tuberosity fractures.

    Science.gov (United States)

    Ji, Jong-Hun; Kim, Weon-Yoo; Ra, Ki-Hang

    2007-10-01

    In cases of displaced greater tuberosity fractures, treatments by arthroscopic-assisted reduction and percutaneous screw fixation have been reported. However, in cases in which there is a comminuted fracture or a minimally displaced fracture combined with concomitant lesions such as rotator cuff tear or labral pathology, it is difficult to reduce the fracture and to treat other pathologies by use of a percutaneous screw. Recently, many surgeons have used the double-row repair method in rotator cuff repair, which provides a tendon-bone interface better suited for biologic healing and restoring normal anatomy. In accordance with this method, we used the arthroscopic technique of double-row suture anchor fixation for a minimally displaced greater tuberosity fracture without additional incision. Initially, debridement was performed on the fracture surface by use of a shaver, and the medial-row anchor was inserted through the anterior portal or the intact cuff. Two lateral-row anchors were inserted just anterior and posterior to the lower margin of the fractured fragment under C-arm guidance. The medial-row sutures and lateral-row sutures were then placed. Arthroscopic double-row suture anchor fixation of a displaced greater tuberosity fracture restores the original footprint of the rotator cuff and normal tendon-bone interface of the displaced greater tuberosity fracture.

  4. 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.

  5. 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.

  6. Interdigitated craniotomy: a simple technique to fix a bone flap with only a single plate.

    Science.gov (United States)

    Takahashi, Noboru; Fujiwara, Kazunori; Saito, Keiichi; Tominaga, Teiji

    2015-10-01

    In pterional craniotomy, fixation plates cause artifacts on postoperative radiological images; furthermore, they often disfigure the scalp in hairless areas. The authors describe a simple technique to fix a cranial bone flap with only a single plate underneath the temporalis muscle in an area with hair, rather than using a plate in a hairless area. The key to this technique is to cut the anterior site of the bone flap at alternate angles on the cut surface. Interdigitation between the bone flap and skull enables single-plate fixation in the area with hair, which reduces artifacts on postoperative radiological images and provides excellent postoperative cosmetic results.

  7. The fixation and saccade P3.

    Science.gov (United States)

    Dandekar, Sangita; Ding, Jian; Privitera, Claudio; Carney, Thom; Klein, Stanley A

    2012-01-01

    Although most instances of object recognition during natural viewing occur in the presence of saccades, the neural correlates of objection recognition have almost exclusively been examined during fixation. Recent studies have indicated that there are post-saccadic modulations of neural activity immediately following eye movement landing; however, whether post-saccadic modulations affect relatively late occurring cognitive components such as the P3 has not been explored. The P3 as conventionally measured at fixation is commonly used in brain computer interfaces, hence characterizing the post-saccadic P3 could aid in the development of improved brain computer interfaces that allow for eye movements. In this study, the P3 observed after saccadic landing was compared to the P3 measured at fixation. No significant differences in P3 start time, temporal persistence, or amplitude were found between fixation and saccade trials. Importantly, sensory neural responses canceled in the target minus distracter comparisons used to identify the P3. Our results indicate that relatively late occurring cognitive neural components such as the P3 are likely less sensitive to post saccadic modulations than sensory neural components and other neural activity occurring shortly after eye movement landing. Furthermore, due to the similarity of the fixation and saccade P3, we conclude that the P3 following saccadic landing could possibly be used as a viable signal in brain computer interfaces allowing for eye movements.

  8. 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

  9. Bioabsorbable thread for tight tying of bones.

    Science.gov (United States)

    Hattori, K; Tomita, N; Tamai, S; Ikada, Y

    2000-01-01

    The purpose of this research was to develop a bioabsorbable thread for tight fixation of fractured bones and to examine its mechanical performance in an in-vitro simulation study. The thread is a blend of bioabsorbable poly(L-lactic acid); (PLLA) and poly(epsilon-caprolactone); (PCL) fibers and can be tightly connected by fusion welding of the PCL fibers. The tying strength of the PLLA-PCL blend thread was 39.7 N, which was comparable to that of stainless steel wire. A testing machine was fabricated to measure the fatigue strength of the tying by simulating bone fixation. The results showed that metal wires always failed because of breakage within 25,000 loading cycles, whereas the blend threads did not fail until 50,000 loading cycles. The looseness of tying for simulated bone fixation by the blend thread was within 1mm even after 50 000 loading cycles. In-vivo testing using rats revealed that the blend thread did not cause any severe inflammatory reaction.

  10. 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.

  11. Computational simulation of bone fracture healing under inverse dynamisation.

    Science.gov (United States)

    Wilson, Cameron J; Schütz, Michael A; Epari, Devakara R

    2017-02-01

    Adaptive finite element models have allowed researchers to test hypothetical relationships between the local mechanical environment and the healing of bone fractures. However, their predictive power has not yet been demonstrated by testing hypotheses ahead of experimental testing. In this study, an established mechano-biological scheme was used in an iterative finite element simulation of sheep tibial osteotomy healing under a hypothetical fixation regime, "inverse dynamisation". Tissue distributions, interfragmentary movement and stiffness across the fracture site were compared between stiff and flexible fixation conditions and scenarios in which fixation stiffness was increased at a discrete time-point. The modelling work was conducted blind to the experimental study to be published subsequently. The simulations predicted the fastest and most direct healing under constant stiff fixation, and the slowest healing under flexible fixation. Although low fixation stiffness promoted more callus formation prior to bridging, this conferred little additional stiffness to the fracture in the first 5 weeks. Thus, while switching to stiffer fixation facilitated rapid subsequent bridging of the fracture, no advantage of inverse dynamisation could be demonstrated. In vivo data remains necessary to conclusively test this treatment protocol and this will, in turn, provide an evaluation of the model's performance. The publication of both hypotheses and their computational simulation, prior to experimental testing, offers an appealing means to test the predictive power of mechano-biological models.

  12. 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.

  13. External fixation of the pelvic girdle as a test for assessing instability of the sacro-iliac joint.

    Science.gov (United States)

    Slätis, P; Eskola, A

    1989-10-01

    External fixation of the pelvic girdle was used in a consecutive series of ten female patients suffering from suspected chronic instability of the sacro-iliac joint. The condition was attributed to pelvic relaxation after pregnancy in seven patients and to trauma in three. External fixation of the pelvis with a trapezoid frame reduced the average radiographic displacement of the symphysis from 5.0 to 2.4 mm in eight patients, relieved the dorsal pain in seven, and markedly improved walking ability in five. Seven of the ten patients were subsequently subjected to an anterior sacro-iliac joint arthrodesis in which square compression plates and autogenous bone grafts were used. At follow-up examination five of these patients were improved, and two unchanged. The results suggest that external fixation of the pelvis is useful in assessing painful sacro-iliac joint instability and should precede surgical intervention.

  14. Therapeutic Targeting of TRPV1 for the Treatment of Chronic Pain Associated with Prostate Cancer Bone Metastasis

    Science.gov (United States)

    2013-07-30

    exhibited metastastatic tumor growth in hind limb bones showed considerable bone destruction, anthough no fractures were observed. Further, we performed...whole animal perfusion with fixative, and subsequently removed the femur and tibia- fibula for tissue sectioning and H&E, as well as immunostainging...metastastatic tumor growth in hind limb bones showed considerable bone destruction, anthough no fractures were observed. Further, we performed whole

  15. Biometric recognition via fixation density maps

    Science.gov (United States)

    Rigas, Ioannis; Komogortsev, Oleg V.

    2014-05-01

    This work introduces and evaluates a novel eye movement-driven biometric approach that employs eye fixation density maps for person identification. The proposed feature offers a dynamic representation of the biometric identity, storing rich information regarding the behavioral and physical eye movement characteristics of the individuals. The innate ability of fixation density maps to capture the spatial layout of the eye movements in conjunction with their probabilistic nature makes them a particularly suitable option as an eye movement biometrical trait in cases when free-viewing stimuli is presented. In order to demonstrate the effectiveness of the proposed approach, the method is evaluated on three different datasets containing a wide gamut of stimuli types, such as static images, video and text segments. The obtained results indicate a minimum EER (Equal Error Rate) of 18.3 %, revealing the perspectives on the utilization of fixation density maps as an enhancing biometrical cue during identification scenarios in dynamic visual environments.

  16. 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

  17. Control and Functions of Fixational Eye Movements

    Science.gov (United States)

    Rucci, Michele; Poletti, Martina

    2016-01-01

    Humans and other species explore a visual scene by rapidly shifting their gaze 2-3 times every second. Although the eyes may appear immobile in the brief intervals in between saccades, microscopic (fixational) eye movements are always present, even when attending to a single point. These movements occur during the very periods in which visual information is acquired and processed and their functions have long been debated. Recent technical advances in controlling retinal stimulation during normal oculomotor activity have shed new light on the visual contributions of fixational eye movements and their degree of control. The emerging body of evidence, reviewed in this article, indicates that fixational eye movements are important components of the strategy by which the visual system processes fine spatial details, enabling both precise positioning of the stimulus on the retina and encoding of spatial information into the joint space-time domain.

  18. Half-bow sliding knot: modified suture technique for scleral fixation using the corneoscleral pocket.

    Science.gov (United States)

    Chee, Soon-Phaik

    2011-09-01

    A modified suture technique for precise knot placement in the Hoffman corneoscleral pocket technique of scleral fixation is described. Both loops of the polypropylene suture passing from the intraocular device through the sclera and conjunctiva are retrieved from the pocket. A loop of suture is pulled through 3 suture throws made using the second suture loop, forming a half bow. Centration of the intraocular lens (IOL)-capsular bag is checked. If the suture tension is too tight, the surgeon can easily undo the knot of the half-bow knot by pulling it free and can then retie the sliding knot. When the IOL-capsular bag is centered, the suture loop is cut and the free end removed. The second suture end is retrieved from the pocket, and knot tying is completed without further adjustment to the tension. Posterior pressure on the intraocular device centers it and settles the knot within the sclera at the fixation point.

  19. Monoaxial Pedicle Screws Are Superior to Polyaxial Pedicle Screws and the Two Pin External Fixator for Subcutaneous Anterior Pelvic Fixation in a Biomechanical Analysis

    Directory of Open Access Journals (Sweden)

    Rahul Vaidya

    2013-01-01

    Full Text Available Purpose. Comparison of monoaxial and polyaxial screws with the use of subcutaneous anterior pelvic fixation. Methods. Four different groups each having 5 constructs were tested in distraction within the elastic range. Once that was completed, 3 components were tested in torsion within the elastic range, 2 to torsional failure and 3 in distraction until failure. Results. The pedicle screw systems showed higher stiffness (4.008 ± 0.113 Nmm monoaxial, 3.638 ± 0.108 Nmm Click-x; 3.634 ± 0.147 Nmm Pangea than the exfix system (2.882 ± 0.054 Nmm in distraction. In failure testing, monoaxial pedicle screw system was stronger (360 N than exfixes (160 N and polyaxial devices which failed if distracted greater than 4 cm (157 N Click-x or 138 N Pangea. The exfix had higher peak torque and torsional stiffness than all pedicle systems. In torsion, the yield strengths were the same for all constructs. Conclusion. The infix device constructed with polyaxial or monoaxial pedicle screws is stiffer than the 2 pin external fixator in distraction testing. In extreme cases, the use of reinforcement or monoaxial systems which do not fail even at 360 N is a better option. In torsional testing, the 2 pin external fixator is stiffer than the pedicle screw systems.

  20. Fixation Property of Copper Triazole Wood Preservatives

    Institute of Scientific and Technical Information of China (English)