WorldWideScience

Sample records for bone fixation devices

  1. 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.

  2. 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.

  3. Monitoring of Postoperative Bone Healing Using Smart Trauma-Fixation Device With Integrated Self-Powered Piezo-Floating-Gate Sensors.

    Science.gov (United States)

    Borchani, Wassim; Aono, Kenji; Lajnef, Nizar; Chakrabartty, Shantanu

    2016-07-01

    Achieving better surgical outcomes in cases of traumatic bone fractures requires postoperative monitoring of changes in the growth and mechanical properties of the tissue and bones during the healing process. While current in-vivo imaging techniques can provide a snapshot of the extent of bone growth, it is unable to provide a history of the healing process, which is important if any corrective surgery is required. Monitoring the time evolution of in-vivo mechanical loads using existing technology is a challenge due to the need for continuous power while maintaining patient mobility and comfort. This paper investigates the feasibility of self-powered monitoring of the bone-healing process using our previously reported piezo-floating-gate (PFG) sensors. The sensors are directly integrated with a fixation device and operate by harvesting energy from microscale strain variations in the fixation structure. We show that the sensors can record and store the statistics of the strain evolution during the healing process for offline retrieval and analysis. Additionally, we present measurement results using a biomechanical phantom comprising of a femur fracture fixation plate; bone healing is emulated by inserting different materials, with gradually increasing elastic moduli, inside a fracture gap. The PFG sensor can effectively sense, compute, and record continuously evolving statistics of mechanical loading over a typical healing period of a bone, and the statistics could be used to differentiate between different bone-healing conditions. The proposed sensor presents a reliable objective technique to assess bone-healing progress and help decide on the removal time of the fixation device.

  4. 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...

  5. 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...

  6. 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

  7. Fixation principles in metaphyseal bone--a patent based review.

    Science.gov (United States)

    Curtis, R; Goldhahn, J; Schwyn, R; Regazzoni, P; Suhm, N

    2005-03-01

    Osteoporotic changes start in cancellous bone due to the underlying pathophysiology. Consequently, the metaphyses are at a higher risk of "osteoporotic" fracture than the diaphysis. Furthermore, implant purchase to fix these fractures is also affected by the poor bone quality. In general, researchers and developers have worked on three different approaches to address the problem of fractures to osteoporotic bone: adapted anchoring techniques, improved load distribution as well as transfer with angular stable screws, and augmentation techniques using bone substitutes. A patent-based review was performed to evaluate which ideas were utilized to improve fixation in osteoporotic, metaphyseal bone, especially in the proximal femur, and to analyze whether the concept had entered clinical use. Anchoring devices that are either extramedullary or intramedullary have a long clinical history. However, demanding surgical techniques and complications, especially in poor quality bone, are justification that such implants and their corresponding surgical techniques need to be improved upon. Expanding elements have been evaluated in the laboratory. The results are promising and the potential of this approach has yet to be fully exploited in the clinics. Internal fixators with angular stable screws open the door for many new anchorage ideas and have great potential for further optimization of load distribution and transfer. Augmentation techniques may improve anchorage in osteoporotic bone. However, the properties of bone substitute materials will need to be modified and improved upon in order to meet the demanding requirements. If we summarise the development process and the clinical use of implants to date, we have to clearly state that more factors than simply biomechanical advantage will determine the clinical success of a new fixation principle or a new implant. Instead, fracture treatment of patients with osteoporosis really needs an interdisciplinary approach!

  8. Machining of a bioactive nanocomposite orthopedic fixation device.

    Science.gov (United States)

    Sparnell, Amie; Aniket; El-Ghannam, Ahmed

    2012-08-01

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

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

    OpenAIRE

    Rubenbauer Bianka; Löffler Thomas; Zaspel Johannes; Wittmann Alexandra; Pieske Oliver; Trentzsch Heiko; Piltz Stefan

    2009-01-01

    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 marke...

  10. 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.

  11. Combining bisphosphonates with allograft bone for implant fixation

    NARCIS (Netherlands)

    Mathijssen, N.M.C.; Buma, P.; Hannink, G.J.

    2014-01-01

    The aim of this review was to discuss the current state of research of combining bisphosphonates with allograft bone for implant fixation. The allograft bone can only be reached by the bisphosphonate once it has been revascularized. However, this can be circumvented by local administration of

  12. A new 3-dimensional head fixation device for brain imaging

    International Nuclear Information System (INIS)

    Goto, Ryoi; Kawashima, Ryuta; Yoshioka, Seiro; Ono, Shuichi; Ito, Hiroshi; Sato, Kazunori; Akaizawa, Takashi; Koyama, Masamichi; Fukuda, Hiroshi

    1995-01-01

    We have developed a new head fixation device for studies of brain function. This device was designed to immobilize subject's heads during image scanning and to precisely reproduce the head position for two different imaging modalities such as MRI and PET. The device consists of a plastic frame, a pillow filled with beads of styrene foam, and a face mask of thermoplastic resin which was originally intended for application in radiotherapy. A bridge for biting was incorporated into the mask for stable fixation. The device enables immobilization of subject's heads with good reproducibility of position at the practical level. Our results indicate that this head fixation system is useful for fixation of head during activation studies using PET. (author)

  13. 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...... 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...... 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...

  14. 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...... in each sheep. The concentric gap (2 mm) surrounding the implant was filled with 1) BAG (autogenous), 2) granules, 3) granules+bone marrow aspirate (BMA, autologous) or 4) allograft. The sheep were euthanized after 6 weeks. Distal femurs were removed and implant-bone samples were divided in two parts...... calculated to assess implant fixation. Results were assessed by One-way ANOVA. P-values less than 0.05 were considered significant. Results One sheep in group 1 had to be euthanized after 4 weeks (excluded). One implant in each group was loosened and could not undergo push-out test (excluded). Group 1...

  15. 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

  16. Biomechanical study of pedicle screw fixation in severely osteoporotic bone.

    Science.gov (United States)

    Cook, Stephen D; Salkeld, Samantha L; Stanley, Tom; Faciane, Albert; Miller, Scot D

    2004-01-01

    Obtaining adequate purchase with standard pedicle screw techniques remains a challenge in poor quality bone. The development of alternate insertion techniques and screw designs was prompted by recognition of potential fixation complications. An expandable pedicle screw design has been shown to significantly improve fixation compared to a conventional screw in poor quality bone. The purpose of this study was to determine if polymethylmethacrylate (PMMA) bone cement augmentation of an expandable pedicle screw can further improve fixation strength compared to the expandable screw alone in severely osteoporotic bone. A technique for cement insertion into the pedicle by means of the cannulated central portion of the expandable screw is also described. The axial pullout strength, stiffness and energy absorbed of cemented and noncemented expandable pedicle screws was determined in cadaveric vertebrae. Twenty-one fresh unembalmed vertebrae from the thoracolumbar spine were used. Radiographs and bone mineral density measurements (BMD) were used to characterize bone quality. Paired cemented and noncemented pedicle screw axial pullout strength was determined through mechanical testing. Mechanical pullout strength, stiffness and energy to failure was correlated with BMD. Overall, there was a 250% increase in mean pullout strength with the cemented expandable screw compared with a noncemented expandable screw including a greater than twofold increase in pullout strength in the most severely osteoporotic bone. The mean stiffness and energy absorbed to failure was also significantly increased. A cemented conventional screw achieved a pullout strength similar to the noncemented expandable screw. PMMA cement augmentation of the expandable pedicle screw may be a viable clinical option for achieving fixation in severely osteoporotic bone.

  17. Resorbable screws for fixation of autologous bone grafts

    NARCIS (Netherlands)

    Raghoebar, GM; Liem, RSB; Bos, RRM; van der Wal, JE; Vissink, A

    The aim of this study was to evaluate the suitability of resorbable screws made of poly (D,L-lactide) acid (PDLLA) for fixation of autologous bone grafts related to graft regeneration and osseointegration of dental implants. In eight edentulous patients suffering from insufficient retention of their

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

    OpenAIRE

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

    2012-01-01

    While contemporary prosthetic devices restore some function to individuals who have lost a limb, there are efforts to develop bio-integrated prostheses to improve functionality. A critical step in advancing this technology will be to securely attach the device to remnant bone. To investigate mechanisms for establishing robust implant fixation in bone while undergoing loading, we previously used a topology optimization scheme to develop optimized orthopaedic implants and then fabricated select...

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

    DEFF Research Database (Denmark)

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

    2005-01-01

    A new bone preparation technique, compaction, has increased fixation of implants inserted with exact-fit or press-fit to bone. Furthermore, a demonstrated spring-back effect of compacted bone might be of potential value in reducing the initial gaps that often exist between clinical inserted...... implants and bone. However, it is unknown whether the compression and breakage of trabeculae during the compaction procedure results in impaired gap-healing of compacted bone. Therefore, we compared compaction with conventional drilling in a canine gap model. Grit-blasted titanium implants (diameter 6 mm......) 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...

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

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    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......Best Poster 5Demineralized bone matrix and human cancellous bone enhance fixation of titanium implants AuthorsBabiker , H.; Ding M.; Overgaard S.InstitutionOrthopaedic Research Laboratory, Department of Orthopaedic Surgery, Odense University Hospital, Clinical Institute, University of Southern......- and autograf as they have the capability of inducing new bone and improving implant fixation through enhancing bone ingrowth. The purpose of this study was to investigate the effect of DBM alone or with CB on the fixation of porous-coated titanium implants.Material and MethodsDBM100 (pure DBM) and CB produced...

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

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Sandri, Monica

    2012-01-01

    Replacement of extensive local bone loss especially in revision joint arthroplasty and spine fusion is a significant clinical challenge. Allograft and autograft have been considered as gold standards for bone replacement. However, there are several disadvantages such as donor site pain, bacterial...... on the early fixation of bone implants in this sheep model. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012....

  2. 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

  3. 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 the 0.75 cc gap surrounding the implant. After 3 weeks, the OP-1 device enhanced implant fixation by 800% (p...

  4. 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...

  5. 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.

  6. Enhancing pedicle screw fixation in the lumbar spine using allograft bone plug interference fixation.

    Science.gov (United States)

    Chrea, Bopha; Malempati, Harsha; Campbell, Jeffrey R; Khan, Sonja; Ching, Randal P; Lee, Michael J

    2014-05-01

    A within-subjects controlled laboratory study. To examine a biological alternative to cement augmentation for pedicle screw fixation comparing bilateral axial pullout tests of augmented and nonaugmented (controls) pedicle screws. Fixation in the osteoporotic spine remains a difficult challenge with failure by loosening or backout. Pedicle screw augmentation has been attempted using polymethylmethacrylate and bioabsorbable calcium cements; however, the potential for extravasation and embolization of cement are becoming increasingly concerning and merit the search for alternative methods to improve screw-anchoring strength. Twenty-four (24) fresh human lumbar vertebrae were tested to compare the pullout strength of augmented and nonaugmented pedicle screws. Two different augmentation strategies were employed using allograft bone plugs (ABPs) and evaluated using 12 specimens per group. Bone mineral density of each specimen was obtained using dual-energy x-ray absorptiometry. The augmented versus nonaugmented pedicle was randomized for each vertebra, and bilateral testing enabled paired statistical analyses. Axial pullout tests were performed using an materials testing system servohydraulic test system, and peak force, failure displacement, and stiffness was obtained for each test and correlated with bone mineral density. Augmentation using 6-mm-diameter ABPs with 6.25-mm-diameter pedicle screws resulted in statistically weaker average pullout strength (775±455 N) than the nonaugmented controls (1233±826 N). When using smaller (5 mm diameter) AGPs with the same diameter screws, there was no statistical difference between average pullout strength for the augmented pedicle screws (1772±652 N) and the nonaugmented screws (1780±575 N). Preliminary study of pedicle screw augmentation using cannulated ABPs showed no improvement of fixation with pedicles in the spine. This was even true in osteoporotic specimens, where augmentation would seem to be of considerable benefit.

  7. The psychological impact of external fixation using the Ilizarov or Orthofix LRS method to treat tibial osteomyelitis with a bone defect.

    Science.gov (United States)

    Abulaiti, Alimujiang; Yilihamu, Yilizati; Yasheng, Tayierjiang; Alike, Yamuhanmode; Yusufu, Aihemaitijiang

    2017-12-01

    To examine the psychological impact of external fixation for a tibial bone defect due to osteomyelitis, and to compare the Orthofix limb reconstruction system (LRS) with the Ilizarov external fixator. The SCL-90-R questionnaire was administered at four different time points (before surgery, while patients wore the external fixation device, when the device was removed, and two to three months after). The scores at the four time points were compared, as were the two different methods of external fixation (Orthofix LRS vs. Ilizarov). The patients experienced a significant adverse impact on their mental health, with the worst outcomes at Time 2 (while wearing the external fixator), but with some negative effects still present even several months after removal of the fixation device. Although the Orthofix LRS and Ilizarov groups showed similar mental health scores at Time 1 (preoperatively) and Time 3 (upon removal of the fixation device), the Orthofix LRS was associated with better scores, specifically in the Hostility (Time 2), Phobic Anxiety (Time 2), Psychoticism (Times 2 and 4), and Other (Time 2) sub-scores, as well as the total score (Times 2 and 4). Although both Ilizarov and Orthofix LRS fixation resolved the bone defects, external fixation had a negative impact on the patients' mental health, which persisted even after removal of the devices. Although both methods led to negative effects on the patients' mental, the impact of the Orthofix LRS was less severe. Copyright © 2017. Published by Elsevier Ltd.

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

    Science.gov (United States)

    Pieske, Oliver; Wittmann, Alexandra; Zaspel, Johannes; Löffler, Thomas; Rubenbauer, Bianka; Trentzsch, Heiko; Piltz, Stefan

    2009-12-15

    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). 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). With the use of DBM, the costs for augmentation of the non-union-site are more expensive compared to ICABG (calculated difference: 160 euro/case). Nevertheless, this study demonstrated that the

  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. Inadvertent Screw Stripping During Ankle Fracture Fixation in Elderly Bone

    Science.gov (United States)

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

    2011-01-01

    Poor screw purchase because of osteoporosis presents difficulties in ankle fracture fixation. The aim of our study was to determine if cortical thickness, unicortical versus bicortical purchase, and bone mineral density are predictors of inadvertent screw stripping and overtightening. Ten paired cadaver ankles (average donor age, 81.7 years; range, 50-97 years) were used for the study. Computed tomography scanning with phantoms of known density was used to determine the bone density along the distal fibula. A standard small-fragment, 7-hole, one-third tubular plate was applied to the lateral surface of the fibula, with 3 proximal bicortical cortical screws and 2 distal unicortical cancellous screws. A posterior plate, in which all 5 screws were cortical and achieved bicortical purchase, was subsequently applied to the same bones and positioned so that the screw holes did not overlap. A torque sensor was used to measure the torque of each screw during insertion (Ti) and then stripping (Ts). The effect of bone density, screw location, cortical thickness, and unicortical versus bicortical purchase on Ti and Ts was checked for significance (P screws were inadvertently stripped and 12% were overtightened. Despite 21% of the screws being stripped or being at risk for stripping, we found no significant predictors to warn of impending screw stripping. Additional work is needed to identify clinically useful predictors of screw stripping. PMID:23569675

  11. 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

  12. Retrograde intramedullary fixation of long bone fractures through ipsilateral traumatic amputation sites.

    Science.gov (United States)

    Wagner, Scott C; Chi, Benjamin B; Gordon, Wade T; Potter, Benjamin K

    2015-06-01

    The technique of retrograde intramedullary fixation of fractures through open traumatic amputations has not been previously described. We performed a retrospective case series at a tertiary-care military hospital setting. Ten patients met inclusion criteria. All were male, and all were injured through improvised explosive device. Outcome measures included the incidence of fracture nonunion, osteomyelitis or acute infection, heterotopic ossification (HO), as well as successful prosthesis fitting and ambulation. Average time to fixation after injury and amputation closure was 11.7 and 12.2 days, respectively. Follow-up averaged 20.2 months. The radiographic union rate was 100%, and time to osseous union averaged 7.5 months. One patient had an amputation site infection requiring revision, but none of the nails was removed for infectious reasons. HO occurred in 7 patients, and 2 patients required revision for symptomatic HO. All patients were successfully fitted with prostheses and able to ambulate. To our knowledge, this is the only series in the literature to specifically describe retrograde intramedullary fixation of long bone fractures through the zone of traumatic amputation sites. The infectious risk is relatively low, whereas the union rate (100%) and successful prosthesis fitting are high. For patients with similar injuries, retrograde intramedullary fixation through the zone of amputation is a viable treatment option.

  13. Drug-eluting Ti wires with titania nanotube arrays for bone fixation and reduced bone infection

    Science.gov (United States)

    Gulati, Karan; Aw, Moom Sinn; Losic, Dusan

    2011-10-01

    Current bone fixation technology which uses stainless steel wires known as Kirschner wires for fracture fixing often causes infection and reduced skeletal load resulting in implant failure. Creating new wires with drug-eluting properties to locally deliver drugs is an appealing approach to address some of these problems. This study presents the use of titanium [Ti] wires with titania nanotube [TNT] arrays formed with a drug delivery capability to design alternative bone fixation tools for orthopaedic applications. A titania layer with an array of nanotube structures was synthesised on the surface of a Ti wire by electrochemical anodisation and loaded with antibiotic (gentamicin) used as a model of bone anti-bacterial drug. Successful fabrication of TNT structures with pore diameters of approximately 170 nm and length of 70 μm is demonstrated for the first time in the form of wires. The drug release characteristics of TNT-Ti wires were evaluated, showing a two-phase release, with a burst release (37%) and a slow release with zero-order kinetics over 11 days. These results confirmed our system's ability to be applied as a drug-eluting tool for orthopaedic applications. The established biocompatibility of TNT structures, closer modulus of elasticity to natural bones and possible inclusion of desired drugs, proteins or growth factors make this system a promising alternative to replace conventional bone implants to prevent bone infection and to be used for targeted treatment of bone cancer, osteomyelitis and other orthopaedic diseases.

  14. 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.

  15. Endosseous Fixation Device for Lapidus Arthrodesis: Technique, Early Experience, and Comparison With Crossed Screw Fixation.

    Science.gov (United States)

    Zelent, Marek E; Neese, David J; Peterson, Paul H

    2015-01-01

    First metatarsal cuneiform joint arthrodesis has been commonly used since the early 1900s for definitive treatment of a variety of conditions involving the medial column of the foot. Early applications of this procedure resulted in a relatively high rate of complications, including malunion and nonunion. We retrospectively examined a novel method of fixation involving an endosseous implant with a nonporous, rough exterior surface and compared it with the traditional crossed screw fixation, considered the standard of care for the procedure. Twenty-one feet in 19 patients served as the control group with crossed screws, and 18 feet in 17 patients served as the trial group using the study device. Null hypothesis testing was used to compare the outcomes parameters between the comparative groups. Postoperatively, the patients were allowed to walk in a prefabricated, removable, below-the-knee cast boot at a mean of 48.3 ± 8.2 days in the control group and 24.4 ± 9.7 days in the trial group. These differences were highly significant (p fixation of the first metatarsal cuneiform arthrodesis procedure and might allow for earlier weightbearing with fewer postoperative complications. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Graft fixation with predetermined tension using a new device, the double spike plate.

    Science.gov (United States)

    Shino, Konsei; Mae, Tatsuo; Maeda, Akira; Miyama, Takahide; Shinjo, Hirotaka; Kawakami, Hideo

    2002-10-01

    To biomechanically evaluate a new fixation device, DSP (Double Spike Plate; Meira Corp, Nagoya, Aichi, Japan), for pullout graft fixation. Biomechanical study. A porcine tibia in which 8-mm diameter drill holes had been made from the medial tibial metaphysis to the anterior cruciate ligament attachment was rigidly fixed to a tension analyzer. A quadrupled graft consisting of 2 double-looped bovine tendons was prepared with No. 3 polyester sutures placed distally. The graft was passed through the drill hole, and its proximal loop ends were rigidly fixed to a load cell for monitoring graft tension. The graft's distal ends were connected to the DSP by tying the sutures to the top hole in the DSP. The graft tension was predetermined at 49 N (n = 5) or 98 N (n = 5). This tension was maintained for 5 minutes with a suture passed through the bottom hole of the DSP. The plate was fixed to the tibia by hammering its spikes into the bone under the index tension. Finally, the fixation was completed by inserting a screw. Although the graft tension immediately increased to 69 +/- 11 N or 133 +/- 14 N during hammering, it gradually reduced to 49 +/- 10 N or 100 +/- 7 N 5 minutes later. This study shows that graft fixation under a predetermined tension can be achieved with the DSP.

  17. Augmentation of anterior vertebral body screw fixation by an injectable, biodegradable calcium phosphate bone substitute.

    Science.gov (United States)

    Bai, B; Kummer, F J; Spivak, J

    2001-12-15

    A biomechanical study to evaluate the effects of a biodegradable calcium phosphate (Ca-P) bone substitute on the fixation strength and bending rigidity of vertebral body screws. To determine if an injectable, biodegradable Ca-P bone substitute provides significant augmentation of anterior vertebral screw fixation in the osteoporotic spine. Polymethylmethacrylate (PMMA) augmented screws have been used clinically; however, there is concern about thermal damage to the neural elements during polymerization of the PMMA as well as its negative effects on bone remodeling. Injectable, biodegradable Ca-P bone substitutes have shown enhanced fixation of pedicle screws. Sixteen fresh cadaveric thoracolumbar vertebrae were randomly divided into two groups: control (no augmentation) (n = 8) and Ca-P bone substitute augmentation (n = 8) groups. Bone-screw fixation rigidity in bending was determined initially and after 10(5) cycles, followed by pullout testing of the screw to failure to determine pullout strength and stiffness. The bone-screw bending rigidity for the Ca-P bone substitute group was significantly greater than the control group, initially (58%) and after cyclic loading (125%). The pullout strength for Ca-P bone substitute group (1848 +/- 166 N) was significantly greater than the control group (665 +/- 92 N) (P pullout for the Ca-P bone substitute groups (399 +/- 69 N/mm) was significantly higher than the control group (210 +/- 51 N/mm) (P screw fixation with a biodegradable Ca-P bone substitute is a potential alternative to the use of PMMA cement.

  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. 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.

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

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2007-01-01

     Introduction: Replacement of extensive local bone loss especially in revision joint arthroplasties is a significant clinical challenge. Autogenous and allogenic cancellous bone grafts have been the gold standard in reconstructive orthopaedic surgery, but it is well known that there is morbidity...... 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...... part of the implant. Specimens are preserving now at - 20°C and wait for the push-out test which is destructive and will be performed on an 858 Bionex MTS hydraulic material testing machine (MTS system cooperation, Minneapolis, Minnesota, USA). The specimens for histological analysis were taken from...

  1. 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.

  2. Comparison of outcomes of two femoral fixation devices in hamstring anterior cruciate ligament reconstruction

    Directory of Open Access Journals (Sweden)

    Miguel Angel Sanchez-Carrasco

    2017-01-01

    Full Text Available Background: Tear of the anterior cruciate ligament (ACL is a common ligamentous injury of the knee. Reconstruction of this ligament is often required to restore functional stability of the knee. Outcome of ACL reconstruction is significantly affected by how the graft is fixed to the bone. This study is to determine if there is a different clinical outcome after cortical versus cortical-cancellous suspension femoral fixation in hamstring based anterior cruciate ligament (ACL reconstruction. Materials and Methods: This is a retrospective comparative study conducted between 2006 and 2010. We enrolled patients who underwent arthroscopic ACL reconstruction. Sixty two patients met inclusion criteria and 41 agreed to come for followup assessment. Median age was of 28 years (range 18–39 years. Demographic baseline profile of both groups was similar. The femoral fixation devices were cortical (n = 16 and cortical-cancellous suspension techniques (n = 25. The average period of evolution at the time of assessment was 40 months (range 12-72 months. The patients were examined according to Lachman test (using Rolimeter knee tester, anterior drawer test, pivot shift test, International Knee Documentation Committee questionnaire, and Tegner-Lysholm knee scoring scale. Results: The objective evaluation of the patients (Lachman test showed better results in terms of stability in the group of patients who underwent the cortical-cancellous suspension method. These differences were not reflected in the assessment of activity level (Tegner-Lysholm, where both groups showed the same results. Conclusions: ACL reconstruction with both cortical and cortical-cancellous suspension femoral fixation techniques show the same clinical results at medium long followup. However, cortical-cancellous fixations seem to provide greater stability to the reconstruction.

  3. Taylor spatial frame fixation in patients with multiple traumatic injuries: study of 57 long-bone fractures.

    Science.gov (United States)

    Sala, Francesco; Elbatrawy, Yasser; Thabet, Ahmed M; Zayed, Mahmoud; Capitani, Dario

    2013-08-01

    To evaluate the Taylor spatial frame (TSF) for primary and definitive fixation of lower limb long-bone fractures in patients with multiple traumatic injuries. Retrospective. Level I trauma center. Consecutive series of 52 patients, 57 fractures (25 femoral and 32 tibial), treated between 2005 and 2009. Forty-nine fractures (86%) were open. Injury Severity Score ≥16 for all patients. Fifty-four fractures (95%) underwent definitive fixation with the TSF and 3 were treated primarily within 48 hours of injury. In 22 cases (39%), fractures were acutely reduced with the TSF, fixed to bone and the struts in sliding mode without further adjustment, and in 35 cases (61%), the total residual deformity correction program was undertaken. Clinical and radiological. Complete union was obtained in 52 fractures (91%) without additional surgery at an average of 29 weeks. Four nonunions and 1 delayed union occurred. Results based on Association for the Study and Application of the Method of Ilizarov criteria: 74% excellent, 16% good, 4% fair, and 7% poor for bone outcomes and 35% excellent, 47% good, and 18% fair for functional outcomes. Eighty-eight percent of patients returned to preinjury work activities. Primary and definitive fixation with the TSF is effective. Advantages include continuity of device until union, reduced risk of infection, early mobilization, restoration of primary defect caused by bone loss, easy and accurate application, convertibility and versatility compared with a monolateral fixator, and improved union rate and range of motion for lower extremity long-bone fractures in patients with multiple traumatic injuries.

  4. A comparative study of internal fixation and intermaxillary fixation on bone repair of mandibular fractures through radiographic subtraction.

    Science.gov (United States)

    Queiroz, Christiano Sampaio; Sarmento, Viviane Almeida; de Azevedo, Roberto Almeida; de Oliveira, Thaís Feitosa Leitão; Bastos, Luana Costa

    2014-07-01

    Conventional radiographic evaluation of fracture healing is not a reliable method, because it depends on the examinator's experience and the quality of the exam. Therefore, serial images differing in density, contrast and geometrical projection can lead to a misdiagnosis on the postoperative fracture healing. Even in good quality images, little changes in calcified tissues often can't be visualized, because of its little sensibility and because of the limited human sight. The use of more sensitive and objective methods could increase the accuracy of this evaluation. This study intended to compare, by digitalized panoramic radiography, the mandible fracture healing after two different types of treatment: open reduction with internal fixation (group 1) and closed reduction with intermaxillary fixation (group 2). It was taken three postoperative radiographs (within a week, a month and three months after treatment), which were digitalized (600 dpi, 8 bits) and adjusted in brightness and size in Photoshop software. Then these images were evaluated by digital subtraction in ImageTool software. The results revealed greater areas of new bone formation in the internal fixation group, in all the evaluated times. Thus, open reduction with internal fixation resulted in more rapid fracture healing than closed reduction with intermaxillary fixation. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

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

    DEFF Research Database (Denmark)

    Babiker, Hassan

      The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants IN SHEEP   Ph.D. Student, Hassan Babiker; Associate Professor, Ph.D. Ming Ding; Professor, dr.med., Soren Overgaard. Department of Orthopaedic Surgery, Odense University Hospital......, Odense, Denmark   Background: Hydroxyapatite and collagen composites (HA/coll) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effect of newly developed HA/coll-composites with and without bone marrow aspirate (BMA) in order to enhance the fixation...

  6. Os acromiale open reduction and internal fixation: a review of iliac crest autogenous bone grafting and local bone grafting.

    Science.gov (United States)

    Atinga, Mordicai; Gregor, Reinhold; Selvaraj, Karthik M; Hong, Thin F

    2018-01-17

    Symptomatic os acromiale are fairly uncommon, and treatment has included fragment excision, decompression, and open reduction and internal fixation. Nonunion rates as high as 40% have been reported after fixation of os acromiale. This study assessed whether union of an os acromiale could be reliably achieved without the use of an iliac crest bone graft. This was a retrospective study of 32 consecutive shoulders that were treated with screw fixation and a local bone graft or iliac crest bone graft. The mean age was 50.3 years (range, 21-74 years), and the mean follow-up was 46.9 months (range, 12-120 months). Fusion was assessed clinically and radiologically. All 32 os acromiale were fused by 3 months on x-ray imaging. There were 18 shoulders in the iliac crest bone graft group and 14 in the local bone graft group. Rotator cuff repairs were performed concomitantly in 25 patients. Hardware was removed in 4 patients, a seroma was drained in 1 patient, and a superficial infection occurred in 1 patient. This is the largest study of os acromiale fixation using screws and a tension band to our knowledge. We report a 100% union rate using this technique, with 13% requiring hardware removal and the occurrence of 1 superficial infection. This study shows a local bone graft is as effective as iliac crest bone graft in achieving fusion. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  7. Arthroscopic Meniscal Allograft Transplantation With Soft-Tissue Fixation Through Bone Tunnels.

    Science.gov (United States)

    Spalding, Tim; Parkinson, Ben; Smith, Nick A; Verdonk, Peter

    2015-10-01

    Meniscal allograft transplantation improves clinical outcomes for patients with symptomatic meniscus-deficient knees. We describe an established arthroscopic technique for meniscal allograft transplantation without the need for bone fixation of the meniscal horns. After preparation of the meniscal bed, the meniscus is parachuted into the knee through a silicone cannula and the meniscal horns are fixed with sutures through bone tunnels. The body of the meniscus is then fixed with a combination of all-inside and inside-out sutures. This technique is reliable and reproducible and has clinical outcomes comparable with those of bone plug fixation techniques.

  8. The head to foot screw fixation. A new technique of percutaneous screw fixation of the scaphoid bone.

    Science.gov (United States)

    Zaraa, Mourad; Ben Slama, Safouane; Mahjoub, Sabri; Sehli, Heithem; Hadj Salah, Méhdi; Mbarek, Mondher

    2017-01-01

    Many techniques have been described for screw fixation of the scaphoid bone. The approach is either proximal or dorsal. A new percutaneous technique is presented by the authors called the head to foot screw fixation. Indications and results are evaluated. It is a percutaneous technique with fixation of the scaphoid bone by two screws introduced in an opposite direction: a proximal screw and a distal screw. No postoperative immobilization was necessary. A prospective study was conducted in 40 patients over a period of three years. The average age was 25 years with extremes of 14 and 44 years. This technique was practiced in fractures (30 cases) and nonunion (10 cases) in which the localization was proximal, corresponding to Schernberg types I, II and III. Forms associated with perilunate dislocation of the carpus were excluded from the study. The results were analysed with a mean of 8 months (6-30). Union was obtained in all the cases. No tendon injury related to percutaneous approach was noted. The technique required a learning curve with progressive decrease in operative time from 45 to 15 minutes. It was necessary in two cases to change protruding screws which were not diagnosed during the first intervention. Percutaneous screw fixation was achieved again in both cases.   Conclusions: The combination in our experience of two screws allowed us to prevent rotation around the unthreated area of a single screw. Our technique, bringing together the head to the foot of the screw, reduces the crowding at the proximal part of the scaphoid bone. This non-invasive method permitted early mobilization with no pain until biological union.

  9. 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.

  10. Design, fabrication and structural optimization of tubular Carbon/Kevlar®/PMMA/Graphene nanoplates composite for bone fixation prosthesis.

    Science.gov (United States)

    Nasiri, Fatemeh; Ajeli, Saeed; Semnani, Dariush; Jahanshahi, Mohsen; Emadi, Rahmatollah

    2018-03-22

    The present work is investigated mechanical properties of tubular carbon/Kevlar® composite coated with poly methyl methacrylate/Graphene nanoplates as used in internal fixation of bones. Carbon fibers are good candidates for developing high-strength biomaterials and due to better stress transfer and electrical properties, they can enhance tissue formation. In order to improve carbon brittleness, ductile Kevlar® was added to the composite. The tubular carbon/ Kevlar® composites have been prepared with tailorable braiding technology by changing fiber pattern and angle in composite structure and number of composite layers. Fuzzy analyses used for optimizing tailorable parameters of 80 prepared samples and then mechanical properties of selected samples are discussed from the viewpoint of mechanical properties required for bone fixation device. Experimental results showed that with optimizing braiding parameters the desired composite structure with mechanical properties close to bone properties could be produced. Results showed that carbon/Kevlar® braid's physical properties, fiber composite distribution and diameter uniformity resulted in matrix uniformity, which enhanced strength and modulus due to better ability for distributing stress on the composite. Finally, as graphene nanoplates demonstrated its potential properties to improve wound healing intended for bone replacement, so reinforcing PMMA matrix with graphene nanoplates enhanced the composite quality as an implant. © 2018 IOP Publishing Ltd.

  11. Biomechanical stability of a supra-acetabular pedicle screw Internal Fixation device (INFIX vs External Fixation and plates for vertically unstable pelvic fractures

    Directory of Open Access Journals (Sweden)

    Vigdorchik Jonathan M

    2012-09-01

    Full Text Available Abstract Background We have recently developed a subcutaneous anterior pelvic fixation technique (INFIX. This internal fixator permits patients to sit, roll over in bed and lie on their sides without the cumbersome external appliances or their complications. The purpose of this study was to evaluate the biomechanical stability of this novel supraacetabular pedicle screw internal fixation construct (INFIX and compare it to standard internal fixation and external fixation techniques in a single stance pelvic fracture model. Methods Nine synthetic pelves with a simulated anterior posterior compression type III injury were placed into three groups (External Fixator, INFIX and Internal Fixation. Displacement, total axial stiffness, and the stiffness at the pubic symphysis and SI joint were calculated. Displacement and stiffness were compared by ANOVA with a Bonferroni adjustment for multiple comparisons Results The mean displacement at the pubic symphysis was 20, 9 and 0.8 mm for external fixation, INFIX and internal fixation, respectively. Plate fixation was significantly stiffer than the INFIX and external Fixator (P = 0.01 at the symphysis pubis. The INFIX device was significantly stiffer than external fixation (P = 0.017 at the symphysis pubis. There was no significant difference in SI joint displacement between any of the groups. Conclusions Anterior plate fixation is stiffer than both the INFIX and external fixation in single stance pelvic fracture model. The INFIX was stiffer than external fixation for both overall axial stiffness, and stiffness at the pubic symphysis. Combined with the presumed benefit of minimizing the complications associated with external fixation, the INFIX may be a more preferable option for temporary anterior pelvic fixation in situations where external fixation may have otherwise been used.

  12. Biomechanical stability of a supra-acetabular pedicle screw internal fixation device (INFIX) vs external fixation and plates for vertically unstable pelvic fractures.

    Science.gov (United States)

    Vigdorchik, Jonathan M; Esquivel, Amanda O; Jin, Xin; Yang, King H; Onwudiwe, Ndidi A; Vaidya, Rahul

    2012-09-27

    We have recently developed a subcutaneous anterior pelvic fixation technique (INFIX). This internal fixator permits patients to sit, roll over in bed and lie on their sides without the cumbersome external appliances or their complications. The purpose of this study was to evaluate the biomechanical stability of this novel supraacetabular pedicle screw internal fixation construct (INFIX) and compare it to standard internal fixation and external fixation techniques in a single stance pelvic fracture model. Nine synthetic pelves with a simulated anterior posterior compression type III injury were placed into three groups (External Fixator, INFIX and Internal Fixation). Displacement, total axial stiffness, and the stiffness at the pubic symphysis and SI joint were calculated. Displacement and stiffness were compared by ANOVA with a Bonferroni adjustment for multiple comparisons The mean displacement at the pubic symphysis was 20, 9 and 0.8 mm for external fixation, INFIX and internal fixation, respectively. Plate fixation was significantly stiffer than the INFIX and external Fixator (P = 0.01) at the symphysis pubis. The INFIX device was significantly stiffer than external fixation (P = 0.017) at the symphysis pubis. There was no significant difference in SI joint displacement between any of the groups. Anterior plate fixation is stiffer than both the INFIX and external fixation in single stance pelvic fracture model. The INFIX was stiffer than external fixation for both overall axial stiffness, and stiffness at the pubic symphysis. Combined with the presumed benefit of minimizing the complications associated with external fixation, the INFIX may be a more preferable option for temporary anterior pelvic fixation in situations where external fixation may have otherwise been used.

  13. Bone compaction enhances fixation of weightbearing titanium implants

    DEFF Research Database (Denmark)

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

    2005-01-01

    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...

  14. Suboccipital neuropathy after bone conduction device placement.

    Science.gov (United States)

    Faber, H T; de Ru, J A

    2013-01-01

    To describe the clinical characteristics of a 70-year-old female with occipital neuropathy following bone conduction device surgery. A 65-year-old woman underwent bone conduction device placement surgery on the left temporal bone. Postoperatively she progressively developed chronic pain at the implantation site. The pain led to minimal neck movement, which resulted in complaints of the shoulder and arm on the left side. She was treated by an orthopaedic surgeon for a frozen shoulder. Pain medication and occipital nerve blocking had no sustained effect on the pain. Occipital neuropathy is a syndrome with continuous aching involving the occipital and parietal scalp caused by trauma or peripheral compression of the occipital nerves. The most common causes of occipital neuropathy are probably direct trauma to the nerve and hypertrophic fibrosis of subcutaneous tissue surrounding the nerve. Scar formation after surgery may therefore cause entrapment of the nerve. We describe a case of occipital neuropathy as a complication of BAHA surgery.

  15. Impacts of pressure bonding fixation on a bone flap depression and resorption in patients with craniotomy.

    Science.gov (United States)

    Matsukawa, Hidetoshi; Miyama, Masataka; Miyazaki, Takanori; Uemori, Genki; Kinoshita, Yu; Sakakibara, Fumihiro; Saito, Norihiro; Tsuboi, Toshiyuki; Noda, Kosumo; Ota, Nakao; Tokuda, Sadahisa; Kamiyama, Hiroyasu; Tanikawa, Rokuya

    2017-07-01

    Fixation of bone flaps after craniotomy is a routine part of every neurosurgical procedure. Common problems encountered are bone flap depression and resorption. Authors performed the pressure-bonding bone flap fixation (PBFF) using absorbable craniofix (AC) and hydroxyapatite wedge (HW). The aim of the present study is to evaluate the efficacy of PBFF to prevent a bone flap depression and resorption in patients treated with craniotomy. Four-hundred fifty-four patients underwent craniotomies. Authors collected the following data: age, sex, type of craniotomy, what kind of surgery, whether bypass surgery was performed, whether surgery was the initial, whether AC and the HW were used, bone flap depression and resorption at 6-month after the craniotomy. PBFF was defined as a bone flap fixation using both AC and HW to impress a bone flap to forehead. The mean age was 62±13years and 404 (89%) patients were women. PBFF was performed in 71 patients (16%), either AC or HW was used in 141 (31%), only AC was used in 116 (25%), and only HW was used in 25 (5.5%). At 6-month after the surgery, a bone flap depression was seen in 38 patients (8.4%), and a bone flap resorption was seen in 66 (15%). Multivariate analysis showed that only a PBBF showed a negative correlation with bone flap depression (p=0.044) and resorption (p=0.011). The results of the present study showed that PBFF reduced a bone flap depression and resorption and provided excellent postoperative cosmetic results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Virtual haptic system for intuitive planning of bone fixation plate placement

    Directory of Open Access Journals (Sweden)

    Kup-Sze Choi

    2017-01-01

    Full Text Available Placement of pre-contoured fixation plate is a common treatment for bone fracture. Fitting of fixation plates on fractured bone can be preoperatively planned and evaluated in 3D virtual environment using virtual reality technology. However, conventional systems usually employ 2D mouse and virtual trackball as the user interface, which makes the process inconvenient and inefficient. In the paper, a preoperative planning system equipped with 3D haptic user interface is proposed to allow users to manipulate the virtual fixation plate intuitively to determine the optimal position for placement on distal medial tibia. The system provides interactive feedback forces and visual guidance based on the geometric requirements. Creation of 3D models from medical imaging data, collision detection, dynamics simulation and haptic rendering are discussed. The system was evaluated by 22 subjects. Results show that the time to achieve optimal placement using the proposed system was shorter than that by using 2D mouse and virtual trackball, and the satisfaction rating was also higher. The system shows potential to facilitate the process of fitting fixation plates on fractured bones as well as interactive fixation plate design.

  17. 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...

  18. The timing of bone SPECT to predict osteonecrosis after internal fixation of femur neck fractures.

    Science.gov (United States)

    Kim, Ji Wan; Ryu, Jin-Sook; Baek, Sora; Byun, Seong-Eun; Chang, Jae Suk

    2017-05-01

    Bone SPECT can be used after a femur neck fracture to assess the circulation of the femoral head in the immediate postoperative period because the blood supply is one of the major factors affecting bone uptake of radiotracer on bone scintigraphy. The purpose of our present study was to investigate whether osteonecrosis of the femoral head (OFH) after internal fixation of femoral neck fracture could be predicted by early and late bone SPECT. This retrospective cohort study enrolled 44 patients (33 women; mean age, 66.9 years) who underwent surgical fixation for femoral neck fractures. Early and late bone SPECT images were obtained within 2 weeks postoperatively and at 3 months postoperatively. Patients were followed up for a minimum of 24 months (average, 34 months). OFH developed in 9 out of 44 patients but no patient showed nonunion. Seventeen patients with normal femoral head uptake on early bone SPECT were healed. Of 27 patients with decreased femoral head uptake on early bone SPECT, 2 patients developed OFH on radiography before 3 months postoperatively, 18 patients recovered to normal uptake on the late SPECT, and the remaining 7 patients still showed decreased uptake on the late SPECT at 3 months postoperatively. All of these 7 cases finally developed OFH on radiography. Bone SPECT can reliably predict the possibility of OFH with after femoral neck fracture at least 3 months after surgery, while early bone SPECT showed low specificity. Clinical. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  19. A simplified application (APP) for the parametric design of screw-plate fixation of bone fractures.

    Science.gov (United States)

    Chung, Chen-Yuan

    2018-01-01

    Screw and plate fixation is commonly used to treat bone fractures. A prototype application (APP) for presurgical simulation was developed and validated by comparing it with current analytical approach and other models. In this APP, alternative plate designs and materials to limit the effects of stress shielding could be tested. In addition, the number and position of screws and the gap between bone and plate that achieved acceptable stability were predicted. The fixation stability providing a situation of interfragmentary strain between 2% and 10% is necessary for callus formation. However, improving the fixation stability leads to a stress shielding effect. The simultaneous alleviation of stress shielding and maintenance of stability are important in fracture healing. In this study, the feasibility of creating a specialized APP to evaluate different screw-plate configurations for diaphyseal femoral fractures was investigated. The ultimate goal is to extend this technique to computer-assisted preoperative planning for orthopedic surgery. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    NARCIS (Netherlands)

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

    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

  1. Is There Enough Evidence to Regularly Apply Bone Screws for Intermaxillary Fixation in Mandibular Fractures?

    NARCIS (Netherlands)

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

    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

  2. Treatment of midshaft clavicular nonunion with plate fixation and autologous bone grafting

    DEFF Research Database (Denmark)

    Olsen, Bo Sanderhoff; Vaesel, M T; Søjbjerg, Jens Ole

    1995-01-01

    , and one had a failure. Thirteen of 16 patients were satisfied with the cosmetic outcome, assessing their cosmetic result as either good or excellent. Rigid plate fixation and restoration of clavicular length with autologous cancellous bone graft is recommended for the treatment of symptomatic clavicular...

  3. Evaluation and comparison of clinical results of femoral fixation devices in arthroscopic anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Aydin, Deniz; Ozcan, Mert

    2016-03-01

    Several femoral fixation devices are available for hamstring tendon autograft in anterior cruciate ligament (ACL) reconstruction, but the best technique is debatable. We hypothesised that different suspensory femoral fixation techniques have no superiority over each other. The aim of this study was to evaluate and compare the clinical results of different suspensory femoral fixation devices in arthroscopic ACL reconstruction. This was a Level III, retrospective, comparative study. A total of 100 consecutive patients who underwent arthroscopic ACL reconstruction in a single institution with a mean follow-up time of 40 months (12-67 months) were divided into three groups according to femoral fixation devices as 'Endobutton' (n=34), 'Transfix' (n=35) and 'Aperfix' (n=31). The length of painful period after surgery, time to return to work and sporting activities, final range of motion, anterior drawer and Lachman tests, knee instability symptoms, International Knee Documentation Committee (IKDC) subjective knee evaluation score, Short Form 36 (SF-36) score, Lysholm knee score and Tegner point of the patients were evaluated and compared between groups. There were no significant differences between the groups. All techniques led to significant recovery in knee instability tests and symptoms. In this study, the clinical results of different suspensory femoral fixation techniques were found to be similar. We believe that different femoral fixation techniques have no effect on clinical results provided that the technique is correctly applied. The surgeon must choose a technique appropriate to his or her experience. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. 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. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  5. 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.

  6. A new, low cost, locking plate for the long-term fixation of a critical size bone defect in the ratfemur: in vivo performance, biomechanical and finite element analysis.

    Science.gov (United States)

    Mataliotakis, George I; Tsouknidas, Alexander; Panteliou, Sofia; Vekris, Marios D; Mitsionis, Grigorios I; Agathopoulos, Simeon; Beris, Alexander E

    2015-01-01

    The optimum fixation device for the critical size bone defect is not established yet. A reliable, feasible and low-cost fixation device for the long-term maintenance of a critical bone defect. A custom-made plate made of poly-methyl-methacrylate was used for the fixation of a critical defect of rats' femurs. The screws were securely fixing both on the plate and the bone. A three point bending test, aimed to resemble the in vivo loading pattern, a Finite Element Analysis and a 24-week in vivo monitoring of the integrity of the plate fixation were utilized. The plate has linear and reproducible behavior. It presents no discontinuities in the stress field of the fixation. Its properties are attributed to the material and the locking principle. It fails beyond the level of magnitude of the normal ambulatory loads. In vivo, 100% of the plates maintained the bone defect intact up to 12 weeks and 85% of them at 24 weeks. This novel locking plate shows optimal biomechanical performance and reliability with high long-term in vivo survival rate. It is fully implantable, inexpensive and easily manufactured. It can be qualified for long term critical defect fixation in bone regeneration studies.

  7. Comparative Study Between Coaptive Film Versus Suture For Wound Closure After Long Bone Fracture Fixation

    Directory of Open Access Journals (Sweden)

    IM Anuar Ramdhan

    2013-03-01

    Full Text Available INTRODUCTION: Coaptive film (i.e., Steri-StripsTM is an adhesive tape used to replace sutures in wound closure. The use of coaptive film for wound closure after long bone fracture fixation has not been well documented in the literature. METHODS: The aim of this prospective, randomized controlled trial comparing coaptive film with sutures for wound closure after long bone fracture fixation was skin closure time, incidence of wound complications and scar width at 12 week follow-up. Forty-five patients underwent femur fracture fixation (22 patients’ wound closed with sutures, 23 with coaptive film. RESULTS: The mean time for skin closure using coaptive film was 171.13 seconds compared to 437.27 seconds using suture. The mean wound lengths in the coaptive film group and suture group were 187.65 mm and 196.73 mm, respectively. One patient in each group had wound complications. CONCLUSION: Coaptive film is a time-saving procedure for skin closure following long bone fracture fixation. There is no difference in the incidence of wound complications and scar width between these two methods of skin closure.

  8. Patient-tailored plate for bone fixation and accurate 3D positioning in corrective osteotomy.

    Science.gov (United States)

    Dobbe, J G G; Vroemen, J C; Strackee, S D; Streekstra, G J

    2013-02-01

    A bone fracture may lead to malunion of bone segments, which gives discomfort to the patient and may lead to chronic pain, reduced function and finally to early osteoarthritis. Corrective osteotomy is a treatment option to realign the bone segments. In this procedure, the surgeon tries to improve alignment by cutting the bone at, or near, the fracture location and fixates the bone segments in an improved position, using a plate and screws. Three-dimensional positioning is very complex and difficult to plan, perform and evaluate using standard 2D fluoroscopy imaging. This study introduces a new technique that uses preoperative 3D imaging to plan positioning and design a patient-tailored fixation plate that only fits in one way and realigns the bone segments as planned. The method is evaluated using artificial bones and renders realignment highly accurate and very reproducible (d(err) < 1.2 ± 0.8 mm and φ(err) < 1.8° ± 2.1°). Application of a patient-tailored plate is expected to be of great value for future corrective osteotomy surgeries.

  9. 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.

  10. MRI study of bioabsorbable poly-L-lactic acid devices used for fixation of fracture and osteotomies

    International Nuclear Information System (INIS)

    Marumo, Keishi; Sato, Yasutomo; Suzuki, Hidehiko; Kurosaka, Daisaburo

    2006-01-01

    The overall clinical results of bioabsorbable fixation devices made of poly-L-lactic acid (PLLA) used for fixation of fractures, bone grafting, and osteotomies have been favorable. However, clinical studies demonstrated no sign of normal bony architecture restored after surgery, although implant channels had been filled with fibrous tissue. The purpose of the present retrospective study was to examine the extent of structural changes in PLLA devices (PLLA-Ds) for fixation of rotational acetabular osteotomies and displaced malleolar ankle fractures using magnetic resonance imaging (MRI). Altogether, 14 patients with osteoarthritis of hip joints and 15 with displaced malleolar ankle fractures were operated on using PLLA-D (NEOFIX). Of these patients, 22 were finally enrolled in the study, and the period from operation to the time of the study ranged from 17 to 78 months. The postoperative radiographic findings were evaluated for union, and changes around the implant holes were classified as sclerosis, resorption, or no change. MRI was carried out to estimate changes in the PLLA-Ds. Bone union was obtained in all cases; clinical complications such as infection, joint effusion, soft tissue irritation due to PLLA-D deviation, and motion pain in the joints were not observed. The MRI study suggested that water content in PLLA-D increased mainly due to biodegradation and that implants were not replaced by bony tissue. The PLLA-Ds were degraded but were not replaced by bony tissue during the observation period. Considering these findings and the assumption that in bony tissues mechanical strength of PLLA-D decreases with time, attention should be paid to mechanical insufficiency, which may occur when the cross-sectional area of a PLLA-D extends beyond the cross-sectional area of the osteosynthesis site. (author)

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

    DEFF Research Database (Denmark)

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

    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....

  12. Distraction osteogenesis using combined locking plate and Ilizarov fixator in the treatment of bone defect: A report of 2 cases

    Directory of Open Access Journals (Sweden)

    John Mukhopadhaya

    2017-01-01

    Full Text Available Distraction osteogenesis and bone transport has been used to reconstruct bone loss defect by allowing new bone to form in the gap. Plate-guided bone transport has been successfully described in literature to treat bone loss defect in the femur, tibia, and mandible. This study reports two cases of fracture of femur with segmental bone loss treated with locking plate fixation and bone transport with Ilizarov ring fixator. At the time of docking, when the transport segment is compressed with bone fragment, the bone fragment is fixed with additional locking or nonlocking screws through the plate. The bone defect size was 7 cm in case 1 and 8 cm in case 2 and the external fixation indexes were 12.7 days/cm and 14 days/cm. No shortening was present in either of our cases. The average radiographic consolidation index was 37 days/cm. Both cases achieved infection-free bone segment regeneration and satisfactorily functional outcome. This technique reduces the duration of external fixation during the consolidation phase, allows correction of length and alignment and provides earlier rehabilitation.

  13. Conventional bone plate fixation of distal radius and ulna fractures in toy breed dogs.

    Science.gov (United States)

    Ramírez, J M; Macías, C

    2016-03-01

    To describe the outcome of bone plate fixation of distal radius and ulna fractures in toy breed dogs treated with conventional bone plates. Records of 15 toy breed dogs with distal radius and ulna fractures were retrospectively reviewed for signalment, method of fixation, complications and clinical and radiographic assessments. A telephone-based owner questionnaire was conducted to determine long-term function and client satisfaction. Age ranged from 4 months to 6 years. Body weight ranged from 1 to 4 kg. Dynamic compression plates were used in 13 dogs and veterinary cuttable plates were used in 2 dogs as the means of fixation. Full radiographic and clinical follow-up data were available for 10 dogs and follow-up was performed between 6 and 8 weeks postoperatively. At that time, all fractures had healed and return to function was considered excellent in all 10 dogs. Five dogs did not return for hospital evaluation because they were judged by their owners to be free of lameness. In two cases, owners could not be contacted by telephone, but the referring veterinarians reported the dogs to be asymptomatic. No major complications occurred. Conventional bone plates are suitable choices for stabilisation of distal radius and ulna fractures in toy breed dogs and are not necessarily correlated with high rates of complication. © 2016 Australian Veterinary Association.

  14. 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

  15. [Image-guided bone consolidation in oncology: Cementoplasty and percutaneous screw fixation].

    Science.gov (United States)

    Buy, Xavier; Cazzato, Roberto Luigi; Catena, Vittorio; Roubaud, Guilhem; Kind, Michele; Palussiere, Jean

    2017-05-01

    Bone metastases are a common finding in oncology. They often induce pain but also fractures which impair quality of life, especially when involving weight-bearing bones. Percutaneous image-guided consolidation techniques play a major role for the management of bone metastases. Cementoplasty aims to stabilize bone and control pain by injecting acrylic cement into a weakened bone. This minimally invasive technique has proven its efficacy for bones submitted to compression forces: vertebra, acetabular roof, and condyles. However, long bone diaphysis should be treated with caution due to lower resistance of the cement subject to torsional forces. The recent improvements of navigation systems allow percutaneous image-guided screw fixation without requiring open surgery. This fast-track procedure avoids postponing introduction of systemic therapies. If needed, cementoplasty can be combined with screw insertion to ensure better anchoring in major osteolysis. Interventional radiology bone consolidation techniques increase the therapeutic field in oncology. A multidisciplinary approach remains mandatory to select the best indications. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  16. Percutaneous internal fixation with Y-STRUT® device to prevent both osteoporotic and pathological hip fractures: a prospective pilot study.

    Science.gov (United States)

    Cornelis, François H; Tselikas, Lambros; Carteret, Thibault; Lapuyade, Bruno; De Baere, Thierry; Le Huec, Jean Charles; Deschamps, Frédéric

    2017-02-09

    We studied Y-STRUT® (Hyprevention, France), a new percutaneous internal fixation device, in combination with bone cementoplasty to prevent hip fracture. Between February 2013 and February 2015, a total of 16 femoral necks in 4 osteoporotic and 12 oncologic patients have been considered for prophylactic consolidation in this prospective multicentre pilot study involving 4 different hospitals. These consolidations were performed percutaneously under fluoroscopic guidance using Y-STRUT®, a dedicated internal fixation device. For osteoporotic patients, orthopaedic surgeons performed the prophylactic consolidations immediately after surgical treatment of a hip fracture (same anaesthesia) in the opposite side. For oncologic patients, without current hip fracture but considered at risk (Mirels score ≥8), interventional radiologists performed the procedures. We report the preliminary results of feasibility, safety and tolerance of these preventive consolidations using Y-STRUT®. Four patients (mean 83 years old) had prophylactic consolidation because of a severe osteoporosis (mean T-score -3.30) resulting in first hip fractures. Ten patients (mean 61 years old) were treated because of impending pathological fractures (mean Mirels score 9) related to femoral neck osteolytic metastases. All the procedures were performed with success. Wound healing was achieved in all cases with no access site complication. Radiographic exams performed at 3 months follow-up revealed that Y-STRUT® was well integrated in the bone. For the osteoporotic cohort, mean pain was 0.9 ± 0.7 at 3 weeks. For the oncologic cohort, it decreases from 3.6 ± 2.9 at baseline to 2.4 ± 0.9 at 2 months. Preliminary results demonstrate the feasibility and safety of Y-STRUT® implantation as well as the tolerance of the device.

  17. In vitro evaluation of allogeneic bone screws for use in internal fixation of transverse fractures created in proximal sesamoid bones obtained from equine cadavers.

    Science.gov (United States)

    Sasaki, Naoki; Takakuwa, Jun; Yamada, Haruo; Mori, Ryuji

    2010-04-01

    To evaluate effectiveness of allogeneic bone screws and pins for internal fixation of midbody transverse fractures of equine proximal sesamoid bones (PSBs) in vitro. 14 forelimbs from cadavers of 3-year-old Thoroughbreds. Allogeneic cortical bone fragments were collected from the limbs of a male Thoroughbred, and cortical bone screws were prepared from the tissue by use of a precision desktop microlathe programmed with the dimensions of a metal cortical bone screw. A midbody transverse osteotomy of each PSB was performed by use of a bone-shaping oscillating saw and repaired via 1 of 3 internal fixation techniques: 1 allogeneic bone screw with 1 allogeneic bone pin (type I; n = 6 PSBs), 2 allogeneic bone screws (type II; 8), or 1 stainless steel cortical bone screw (control repair; 6). Mechanical tension measurements were obtained by use of a commercially available materials testing system. Mean +/- SD tensile strength (TS) was 668.3 +/- 216.6 N for type I repairs, 854.4 +/- 253.2 N for type II repairs, and 1,150.0 +/- 451.7 N for control repairs. Internal fixation of PSB fractures by the use of allogeneic bone screws and bone pins was successful. Although mean TS of control repairs with stainless steel cortical bone screws was greater than the mean TS of type I and type II repairs, the difference between type II and control repairs was not significant. Allogeneic screws may advance healing and result in fewer complications in a clinical setting.

  18. Delayed Union of a Sacral Fracture: Percutaneous Navigated Autologous Cancellous Bone Grafting and Screw Fixation

    International Nuclear Information System (INIS)

    Huegli, R. W.; Messmer, P.; Jacob, A. L.; Regazzoni, P.; Styger, S.; Gross, T.

    2003-01-01

    Delayed or non-union of a sacral fracture is a serious clinical condition that may include chronic pain, sitting discomfort, gait disturbances, neurological problems, and inability to work. It is also a difficult reconstruction problem. Late correction of the deformity is technically more demanding than the primary treatment of acute pelvic injuries. Open reduction, internal fixation (ORIF), excision of scar tissue, and bone grafting often in a multi-step approach are considered to be the treatment of choice in delayed unions of the pelvic ring. This procedure implies the risk of neurological and vascular injuries, infection, repeated failure of union, incomplete correction of the deformity, and incomplete pain relief as the most important complications. We report a new approach for minimally invasive treatment of a delayed union of the sacrum without vertical displacement. A patient who suffered a Malgaigne fracture (Tile C1.3) was initially treated with closed reduction and percutaneous screw fixation (CRPF) of the posterior pelvic ring under CT navigation and plating of the anterior pelvic ring. Three months after surgery he presented with increasing hip pain caused by a delayed union of the sacral fracture. The lesion was successfully treated percutaneously in a single step procedure using CT navigation for drilling of the delayed union, autologous bone grafting, and screw fixation

  19. 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

  20. 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...

  1. 21 CFR 888.3030 - Single/multiple component metallic bone fixation appliances and accessories.

    Science.gov (United States)

    2010-04-01

    ...-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners... implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a... involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force...

  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 construct in a perfusion bioreactor has been shown to produce viable bone graft materials. This study aimed at producing larger amounts of viable bone graft material (hydroxyapatite 70% and β-tricalcium-phosphate 30%) in a novel perfusion bioreactor. The abilities of the bioreactor-activated graft material...... allograft, granules, granules with bone marrow aspirate or bioreactor-activated graft material. Following an observation time of 6 weeks, early implant fixation and bone formation were assessed by micro-CT scanning, mechanical testing, and histomorphometry. Bone formations were seen in all groups, while...

  3. 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 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 < 0.05). CONCLUSIONS PLIF with CBT screw fixation for DS provided comparable improvement of clinical symptoms with PLIF using traditional PS fixation. However, the successful 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.

  4. Application of bioabsorbable screw fixation for anterior cervical decompression and bone grafting

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    Bo Zhao

    Full Text Available OBJECTIVES: To examine the application of bioabsorbable screws for anterior cervical decompression and bone grafting fixation and to study their clinical effects in the treatment of cervical spondylosis. METHODS: From March 2007 to September 2012, 56 patients, 36 males and 20 females (38-79 years old, average 58.3±9.47 years, underwent a novel operation. Grafts were fixed by bioabsorbable screws (PLLA, 2.7 mm in diameter after anterior decompression. The bioabsorbable screws were inserted from the midline of the graft bone to the bone surface of the upper and lower vertebrae at 45 degree angles. Patients were evaluated post-operatively to observe the improvement of symptoms and evaluate the fusion of the bone. The Japanese Orthopaedic Association (JOA score was used to evaluate the recovery of neurological functions. RESULTS: All screws were successfully inserted, with no broken screws. The rate of symptom improvement was 87.5%. All of the grafts fused well with no extrusion. The average time for graft fusion was 3.8±0.55 months (range 3-5 months. Three-dimensional reconstruction of CT scans demonstrated that the grafts fused with adjacent vertebrae well and that the screws were absorbed as predicted. The MRI findings showed that the cerebrospinal fluid was unobstructed. No obvious complications appeared in any of the follow-up evaluations. CONCLUSIONS: Cervical spondylosis with one- or two-level involvement can be effectively treated by anterior decompression and bone grafting with bioabsorbable screw fixation. This operative method is safe and can avoid the complications induced by metal implants.

  5. THE EXPERIENCE TREATMENT BY THE EXTERNAL FIXATION DEVICE OF OUR DESIGN

    OpenAIRE

    KARIMOV MURODULLO YULDASHOVICH; SALOKHIDDINOV FAKHRIDDIN BAKHRIDDINOVICH

    2016-01-01

    The apparatus for osteosynthesis of long bone fractures has several advantages comparing to the traditional treatment methods. The rod device is easy to use and comfortable for patients. We evaluated the efficiency of the rod device in patients with fractures of the long bones. For the period from 2011 to 2015 25 patients with fractures of the femur and tibia with multiple and associated injuries were treated using the rod device of our design. The average age of patients was 43.4 years (rang...

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

    Science.gov (United States)

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

    2012-10-11

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

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

    Science.gov (United States)

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

    2012-01-01

    While contemporary prosthetic devices restore some function to individuals who have lost a limb, there are efforts to develop bio-integrated prostheses to improve functionality. A critical step in advancing this technology will be to securely attach the device to remnant bone. To investigate mechanisms for establishing robust implant fixation in bone while undergoing loading, we previously used a topology optimization scheme to develop optimized orthopaedic implants and then fabricated selected designs from titanium (Ti)-alloy with selective laser sintering (SLS) technology. In the present study, we examined how implant architecture and mechanical stimulation influence osseointegration within an in vivo environment. To do this, we evaluated three implant designs (two optimized and one non-optimized) using a unique in vivo model that applied cyclic, tension/ compression loads to the implants. Eighteen (six per implant design) adult male canines had implants surgically placed in their proximal, tibial metaphyses. Experimental duration was 12 weeks; daily loading (peak load of ±22N for 1000 cycles) was applied to one of each animal’s bilateral implants for the latter six weeks. Following harvest, osseointegration was assessed by non-destructive mechanical testing, micro-computed tomography (microCT) and back-scatter scanning electron microscopy (SEM). Data revealed that implant loading enhanced osseointegration by significantly increasing construct stiffness, peri-implant trabecular morphology, and percentages of interface connectivity and bone ingrowth. While this experiment did not demonstrate a clear advantage associated with the optimized implant designs, osseointegration was found to be significantly influenced by aspects of implant architecture. PMID:22951278

  8. Stress analysis of implant-bone fixation at different fracture angle

    Science.gov (United States)

    Izzawati, B.; Daud, R.; Afendi, M.; Majid, MS Abdul; Zain, N. A. M.; Bajuri, Y.

    2017-10-01

    Internal fixation is a mechanism purposed to maintain and protect the reduction of a fracture. Understanding of the fixation stability is necessary to determine parameters influence the mechanical stability and the risk of implant failure. A static structural analysis on a bone fracture fixation was developed to simulate and analyse the biomechanics of a diaphysis shaft fracture with a compression plate and conventional screws. This study aims to determine a critical area of the implant to be fractured based on different implant material and angle of fracture (i.e. 0°, 30° and 45°). Several factors were shown to influence stability to implant after surgical. The stainless steel, (S. S) and Titanium, (Ti) screws experienced the highest stress at 30° fracture angle. The fracture angle had a most significant effect on the conventional screw as compared to the compression plate. The stress was significantly higher in S.S material as compared to Ti material, with concentrated on the 4th screw for all range of fracture angle. It was also noted that the screws closest to the intense concentration stress areas on the compression plate experienced increasing amounts of stress. The highest was observed at the screw thread-head junction.

  9. Stress corrosion cracking of an aluminum alloy used in external fixation devices.

    Science.gov (United States)

    Cartner, Jacob L; Haggard, Warren O; Ong, Joo L; Bumgardner, Joel D

    2008-08-01

    Treatment for compound and/or comminuted fractures is frequently accomplished via external fixation. To achieve stability, the compositions of external fixators generally include aluminum alloy components due to their high strength-to-weight ratios. These alloys are particularly susceptible to corrosion in chloride environments. There have been several clinical cases of fixator failure in which corrosion was cited as a potential mechanism. The aim of this study was to evaluate the effects of physiological environments on the corrosion susceptibility of aluminum 7075-T6, since it is used in orthopedic external fixation devices. Electrochemical corrosion curves and alternate immersion stress corrosion cracking tests indicated aluminum 7075-T6 is susceptible to corrosive attack when placed in physiological environments. Pit initiated stress corrosion cracking was the primary form of alloy corrosion, and subsequent fracture, in this study. Anodization of the alloy provided a protective layer, but also caused a decrease in passivity ranges. These data suggest that once the anodization layer is disrupted, accelerated corrosion processes occur. (c) 2007 Wiley Periodicals, Inc.

  10. Osteosynthesis of ununited femoral neck fracture by internal fixation combined with iliac crest bone chips and muscle pedicle bone grafting

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    D D Baksi

    2016-01-01

    Full Text Available Background: Ununited femoral neck fracture is seen commonly in developing countries due to delayed presentation or failure of primary internal fixation. Such fractures, commonly present with partial or total absorption of femoral neck, osteonecrosis of femoral head in 8-30% cases with upward migration of trochanter posing problem for osteosynthesis, especially in younger individuals. Several techniques for treatment of such conditions are described like osteotomies or nonvascularied cortical or cancellous bone grafting provided varying degrees of success in terms of fracture union but unsatisfactory long term results occurred due to varying incidence of avascular necrosis (AVN of femoral head. Moreover, in presence of AVN of femoral head neither free fibular graft nor cancellous bone graft is satisfactory. The vascularied bone grafting by deep circumflex iliac artery based on iliac crest bone grafting, free vascularied fibular grafting and muscle pedicle periosteal grafting showed high incidence of success rate. Osteosynthesis is the preferred treatment of choice in ununited femoral neck fracture in younger individuals. Materials and Methods: Of the 293 patients operated during the period from June 1977 to June 2009, 42 were lost to followup. Seven patients with gluteus medius muscle pedicle bone grafting (MPBG were excluded. Thus, out of 244 patients, 208 (85.3% untreated nonunion and 36 (14.7% following failure of primary internal fixation were available for studies. Time interval between the date of injury and operation in untreated nonunion cases was mean 6.5 months and in failed internal fixation cases was mean 11.2 months. Ages of the patients varied from 16 to 55 years. Seventy patients had partial and 174 had subtotal absorption of the femoral neck. Evidence of avascular necrosis (AVN femoral head was found histologically in 135 (54.3% and radiologically in 48 (19.7% patients. The patients were operated by open reduction of fracture

  11. Interfacial sliding properties of bone screw materials and their effect on screw fixation strength.

    Science.gov (United States)

    Koistinen, Arto P; Korhonen, Hannu; Kröger, Heikki; Lappalainen, Reijo

    2014-09-05

    This study examined the effect of interfacial sliding and test material properties on the fixation strength and insertional properties of self-tapping bone screws. Various substitute materials (polyacetal [POM], poly(methyl methacrylate) [PMMA] and E-glass-filled Epoxy [Sawbones®]) for human bone were evaluated, and the results were compared with the findings for cadaver bone.
 Initial coefficient of friction (CoF) of the screw material stainless steel AISI316 was tested using a pin-on-disk apparatus, and the screws were exposed to pullout tests after insertion torque tests. The effect of a smooth diamond-like carbon (DLC) coating was studied by applying the coating on both CoF test balls and bone screws.
 Mechanical properties of test blocks strongly correlated to both pullout strength and insertion torque of the screws: for noncoated 2.7-mm screws, tensile strength correlated to pullout strength and insertion torque, with Pearson correlation coefficients r=0.977 and r=0.738, respectively. In contrast, CoF correlated strongly to screw insertion torque but not to pullout strength in bone substitute materials (for noncoated 2.7-mm screws, r=0.652 and r=0.248, respectively). There were no significant differences in CoF using noncoated and DLC-coated screw materials against bone substitutes.
 Proper materials for in vitro testing help in evaluating the biomechanics of the implants in advance. However, choosing the material needs attention, as their ability to model human bone depends on test type.

  12. 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.

  13. Management of extra-articular segmental defects in long bone using a titanium mesh cage as an adjunct to other methods of fixation.

    Science.gov (United States)

    Attias, N; Thabet, A M; Prabhakar, G; Dollahite, J A; Gehlert, R J; DeCoster, T A

    2018-05-01

    Aims This study reviews the use of a titanium mesh cage (TMC) as an adjunct to intramedullary nail or plate reconstruction of an extra-articular segmental long bone defect. Patients and Methods A total of 17 patients (aged 17 to 61 years) treated for a segmental long bone defect by nail or plate fixation and an adjunctive TMC were included. The bone defects treated were in the tibia (nine), femur (six), radius (one), and humerus (one). The mean length of the segmental bone defect was 8.4 cm (2.2 to 13); the mean length of the titanium mesh cage was 8.3 cm (2.6 to 13). The clinical and radiological records of the patients were analyzed retrospectively. Results The mean time to follow-up was 55 months (12 to 126). Overall, 16 (94%) of the patients achieved radiological filling of their bony defect and united to the native bone ends proximally and distally, resulting in a functioning limb. Complications included device failure in two patients (12%), infection in two (12%), and wound dehiscence in one (6%). Four patients (24%) required secondary surgery, four (24%) had a residual limb-length discrepancy, and one (6%) had a residual angular limb deformity. Conclusion A titanium mesh cage is a useful adjunct in the treatment of an extra-articular segmental defect in a long bone. Cite this article: Bone Joint J 2018;100-B:646-51.

  14. Strength comparison of allogenic bone screws, bioabsorbable screws, and stainless steel screw fixation.

    Science.gov (United States)

    Rano, James A; Savoy-Moore, Ruth T; Fallat, Lawrence M

    2002-01-01

    Allogenic bone screws are new to the fixation market and have yet to be tested against current fixation materials. An in vitro comparison of the same sizes of stainless steel, bioabsorbable, and allogenic bone screws was undertaken to assess screw resistance to the forces of bending, pullout, and shear. Using aluminum plates to support the screws, forces up to 1000 Newtons were applied to six to eight samples of each type of screw. During each test, stainless steel screws withstood the maximum force that could be exerted by the testing apparatus without failing (bending, 113.9 +/- 11.8 N mean +/- SE; pullout 999.1 +/- 33.7 N; and shear, 997.5 +/- 108.8 N). In each test, compared to bioabsorbable screws, allogenic bone screws failed faster (pullout, allogenic: 12.4 +/- 1.1 seconds vs. bioabsorbable, 120.6 +/- 13.8 seconds; p = .001; bending, allogenic: 53.4 +/- 4.8 seconds vs. bioabsorbable, 201.9 +/- 11.1 seconds; p = .001; shear, allogenic 13.5 +/- 1.4 seconds vs. bioabsorbable, 43.8 +/- 0.9 seconds; p = .001) under equivalent (pullout: bioabsorbable, 385.0 +/- 18.4 N vs. allogenic, 401.0 +/- 35.9 N; p = .001) or lower (bending, allogenic: 4.7 +/- 0.2 N vs. bioabsorbable, 11.0 +/- 0.9 N; p = .675; shear, allogenic: 312.1 +/- 15.5 N vs. bioabsorbable 680.9 +/- 8.5 N; p = .001) loads, and in a highly variable fashion. Overall, the bioabsorbable screws withstood the forces of bending, pullout, and shear better than the allogenic screws, and stainless steel screws outperformed both bioabsorbable and allogenic screws. Despite these results, allogenic screws could still be useful in compliant patients who would benefit from their osteoconductive properties.

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

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    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

  16. 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.

  17. Fully Threaded Versus Partially Threaded Screws: Determining Shear in Cancellous Bone Fixation.

    Science.gov (United States)

    Downey, Michael W; Kosmopoulos, Victor; Carpenter, Brian B

    2015-01-01

    Many researchers have studied and compared various forms of intraosseous fixation. No studies have examined the effects of shear through stiffness and failure strength of a fully threaded versus a partially threaded screw. Our hypothesis was that the fully threaded lag screw technique would provide greater shear strength and resistance. Thirty-six synthetic sawbone blocks were used to test screw fixation. In group 1 (n = 9), 2 blocks were fixed together using a fully threaded 4.0-mm stainless steel cancellous bone screw and the lag technique. In group 2 (n = 8), 2 blocks were fixed together using the standard manufacturer-recommended method for inserting 4.0-mm partially threaded stainless steel cancellous bone screws. The constructs were then mechanically tested. Shear was applied by compressing each construct at an axial displacement rate of 0.5 mm/s until failure. The fully threaded screw had a significantly greater (p = .026) initial stiffness (106.4 ± 15.8 N/mm) than the partially threaded screw (80.1 ± 27.5 N/mm). The yield load and displacement for the fully threaded group (429.4 ± 11.7 N and 7.2 ± 0.35 mm) were 64% and 67% greater than those for the partially threaded screw group (261.4 ± 26.1 N and 4.3 ± 1.03 mm), respectively. The results of the present study have demonstrated the importance of a full-thread construct to prevent shear and to decrease strain at the fracture. The confirmation of our hypothesis questions the future need and use of partially threaded screws for cancellous bone fixation. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Symptomatic non-union of the carpal scaphoid: Matti-Russe bone grafting versus Herbert screw fixation.

    Science.gov (United States)

    Parkinson, R W; Hodgkinson, J P; Hargadon, E J

    1989-05-01

    We have reviewed 19 patients who have had Matti-Russe bone grafting and 16 patients who have had Herbert screw fixation for symptomatic non-union of the carpal scaphoid. The success rate in both groups was similar, 74 per cent in the Matti-Russe group and 71 per cent in the Herbert screw group. Only five patients in the Herbert screw group had bone grafts. The advantages and disadvantages of both methods of treatment are discussed.

  19. Cortical bone trajectory screws fixation in lumbar adjacent segment disease: A technique note with case series.

    Science.gov (United States)

    Chen, Chao-Hsuan; Huang, Hsieng-Ming; Chen, Der-Cherng; Wu, Chih-Ying; Lee, Han-Chun; Cho, Der-Yang

    2018-02-01

    Lumbar adjacent segment disease after lumbar fusion surgery often requires surgical intervention. However, subsequent surgical treatment often needs to expose and remove all of the previous instruments. This additional surgery leads to significant post-operative pain, muscular fibrosis, poor wound healing and infection, etc. From October 2015 to March 2016, we collected six cases underwent cortical bone trajectory screws fixation with minimal invasive inter-body cage fusion for lumbar adjacent segment disease. Patients in the study all had improvement after surgery without recurrence or instruments failure during follow-up. The technique negates removal of pre-existing instruments and when combined with minimal invasive fusion surgery, the wound length, blood loss and soft tissue damage could be reduced compared with traditional surgery. We introduce the surgical procedures in detail and wish this technique could be an option for spine surgeons who encounter a similar situation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Cortical bone trajectory screw fixation versus traditional pedicle screw fixation for 2-level posterior lumbar interbody fusion: comparison of surgical outcomes for 2-level degenerative lumbar spondylolisthesis.

    Science.gov (United States)

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

    2018-01-01

    OBJECTIVE The cortical bone trajectory (CBT) screw technique is a new nontraditional pedicle screw (PS) insertion method. However, the biomechanical behavior of multilevel CBT screw/rod fixation remains unclear, and surgical outcomes in patients after 2-level posterior lumbar interbody fusion (PLIF) using CBT screw fixation have not been reported. Thus, the purposes of this study were to examine the clinical and radiological outcomes after 2-level PLIF using CBT screw fixation for 2-level degenerative lumbar spondylolisthesis (DS) and to compare these outcomes with those after 2-level PLIF using traditional PS fixation. METHODS The study included 22 consecutively treated patients who underwent 2-level PLIF with CBT screw fixation for 2-level DS (CBT group, mean follow-up 39 months) and a historical control group of 20 consecutively treated patients who underwent 2-level PLIF using traditional PS fixation for 2-level DS (PS group, mean follow-up 35 months). Clinical symptoms were evaluated using the Japanese Orthopaedic Association (JOA) scoring system. Bony union was assessed by dynamic plain radiographs and CT images. Surgery-related complications, including symptomatic adjacent-segment disease (ASD), were examined. RESULTS The mean operative duration and intraoperative blood loss were 192 minutes and 495 ml in the CBT group and 218 minutes and 612 ml in the PS group, respectively (p 0.05, respectively). The mean JOA score improved significantly from 12.3 points before surgery to 21.1 points (mean recovery rate 54.4%) at the latest follow-up in the CBT group and from 12.8 points before surgery to 20.4 points (mean recovery rate 51.8%) at the latest follow-up in the PS group (p > 0.05). Solid bony union was achieved at 90.9% of segments in the CBT group and 95.0% of segments in the PS group (p > 0.05). Symptomatic ASD developed in 2 patients in the CBT group (9.1%) and 4 patients in the PS group (20.0%, p > 0.05). CONCLUSIONS Two-level PLIF with CBT screw fixation

  1. In Vitro Corrosion Assessment of Additively Manufactured Porous NiTi Structures for Bone Fixation Applications

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    Hamdy Ibrahim

    2018-03-01

    Full Text Available NiTi alloys possess distinct functional properties (i.e., shape memory effect and superelasticity and biocompatibility, making them appealing for bone fixation applications. Additive manufacturing offers an alternative method for fabricating NiTi parts, which are known to be very difficult to machine using conventional manufacturing methods. However, poor surface quality, and the presence of impurities and defects, are some of the major concerns associated with NiTi structures manufactured using additive manufacturing. The aim of this study is to assess the in vitro corrosion properties of additively manufactured NiTi structures. NiTi samples (bulk and porous were produced using selective laser melting (SLM, and their electrochemical corrosion characteristics and Ni ion release levels were measured and compared with conventionally fabricated NiTi parts. The additively manufactured NiTi structures were found to have electrochemical corrosion characteristics similar to those found for the conventionally fabricated NiTi alloy samples. The highest Ni ion release level was found in the case of 50% porous structures, which can be attributed to their significantly higher exposed surface area. However, the Ni ion release levels reported in this work for all the fabricated structures remain within the range of most of values for conventionally fabricated NiTi alloys reported in the literature. The results of this study suggest that the proposed SLM fabrication process does not result in a significant deterioration in the corrosion resistance of NiTi parts, making them suitable for bone fixation applications.

  2. Progressive femoral cortical and cancellous bone density loss after uncemented tapered-design stem fixation

    Science.gov (United States)

    Nowak, Tobias E; Haeberle, Lothar; Mueller, Lars P; Kress, Alexander; Voelk, Michael; Pfander, David; Forst, Raimund; Schmidt, Rainer

    2010-01-01

    Background Aseptic implant loosening and periprosthetic bone loss are major problems after total hip arthroplasty (THA). We present an in vivo method of computed tomography (CT) assisted osteodensitometry after THA that differentiates between cortical and cancellous bone density (BD) and area around the femoral component. Method Cortical and cancellous periprosthetic femoral BD (mg CaHA/mL), area (mm2) and contact area between the prothesis and cortical bone were determined prospectively in 31 patients 10 days, 1 year, and 6 years after uncemented THA (mean age at implantation: 55 years) using CT-osteodensitometry. Results 6 years postoperatively, cancellous BD had decreased by as much as 41% and cortical BD by up to 27% at the metaphyseal portion of the femur; this decrease was progressive between the 1-year and 6-year examinations. Mild cortical hypertrophy was observed along the entire length of the diaphysis. No statistically significant changes in cortical BD were observed along the diaphysis of the stem. Interpretation Periprosthetic CT-assisted osteodensitometry has the technical ability to discriminate between cortical and cancellous bone structures with respect to strain-adapted remodeling. Continuous loss of cortical and cancellous BD at the femoral metaphysis, a homeostatic cortical strain configuration, and mild cortical hypertrophy along the diaphysis suggest a diaphyseal fixation of the implanted stem. CT-assisted osteodensitometry has the potential to become an effective instrument for quality control in THA by means of in vivo determination of periprosthetic BD, which may be a causal factor in implant loosening after THA. PMID:20180716

  3. Evaluation of body image and self-esteem in patients with external fixation devices: a Turkish perspective.

    Science.gov (United States)

    Büyükyilmaz, Funda; Sendir, Merdiye; Salmond, Susan

    2009-01-01

    This descriptive study aimed to describe the body image and self-esteem of patients with external fixation devices. Fifty patients with external fixation devices who came for follow-up to the Ilizarov Outpatient Clinic of a university hospital in Turkey were included in this study. Data were collected by using a Demographic Questionnaire Form, Multidimensional Body-Self Relations Questionnaire (MBSRQ), and Coppersmith Self-Esteem Inventory. The perceived body image (197.58 +/- 25.14) and self-esteem (65.28 +/- 17.97) of the patients with external fixation devices were in the moderate range. There was no significant correlation between body image and self-esteem. Self-esteem was correlated with one's perception of whether external fixation impacted one's appearance and whether one wanted to avoid being seen by certain individuals because of the appearance of the external fixator. The study highlighted that body image disturbance and threats to self-esteem are not universal with the use of external fixation and need to be assessed individually.

  4. Internal fixation of proximal fractures of the 2nd and 4th metacarpal and metatarsal bones using bioabsorbable screws.

    Science.gov (United States)

    Mageed, M; Steinberg, T; Drumm, N; Stubbs, N; Wegert, J; Koene, M

    2018-03-01

    Fractures involving the proximal one-third of the splint bone are relatively rare and are challenging to treat. A variety of management techniques have been reported in the literature. The aim of this retrospective case series was to describe the clinical presentation and evaluate the efficacy of bioabsorbable polylactic acid screws in internal fixation of proximal fractures of the 2nd and 4th metacarpal and metatarsal bones in horses. The medical records, diagnostic images and outcome of all horses diagnosed with a proximal fracture of the splint bones and treated with partial resection and internal fixation of the proximal stump using bioabsorbable polylactic acid screws between 2014 and 2015 were reviewed. Eight horses met the inclusion criteria. The results showed that there were no complications encountered during screw placement or postoperatively. Six horses returned to full work 3 months after the operation and two horses remained mildly lame. On follow-up radiographs 12 months postoperatively (n = 2) the screws were not completely absorbed. The screws resulted in a cone-shaped radiolucency, which was progressively replaced from the outer margins by bone sclerosis. The use of bioabsorbable screws for fixation of proximal fractures of the splint bone appears to be a safe and feasible technique and may offer several advantages over the use of traditional metallic implants. © 2018 Australian Veterinary Association.

  5. The effect of posterior spinal fixation with bone cement upon vertebral growth in dogs. An experimental study.

    Science.gov (United States)

    Moon, M S; Ok, I Y

    1980-01-01

    In an experimental study the authors tried to clarify the effect on vertebral growth and spinal curvature in dogs following fixation of the posterior elements of the spine at different levels using bone cement. In three separate experimental groups a segment of the dorsal spine, the dorso-lumbar spine or the lumbar spine was securely fixed with bone cement incorporating a radio-opaque wire marker. Growth of the spine was observed with renal X-rays over a six-month period and the following results obtained: 1. Growth in height of the vertebra was not affected by the fixation; 2. The intervertebral disc spaces widened anteriorly and narrowed posteriorly even when fracture of the bone cement occurred; 3. Increasing lordosis developed in all three experimental groups even when a physiological kyphosis was normally present. The greatest increase occurred in the lumbar spine; 4. Fracture of the cement occurred consistently when attempting to secure the dorso-lumbar junction.

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

    DEFF Research Database (Denmark)

    Jensen, T B; Overgaard, S; Lind, M

    2007-01-01

    Impacted bone allograft is often used in revision joint replacement. Hydroxyapatite granules have been suggested as a substitute or to enhance morcellised bone allograft. We hypothesised that adding osteogenic protein-1 to a composite of bone allograft and non-resorbable hydroxyapatite granules...... (ProOsteon) would improve the incorporation of bone and implant fixation. We also compared the response to using ProOsteon alone against bone allograft used in isolation. We implanted two non-weight-bearing hydroxyapatite-coated implants into each proximal humerus of six dogs, with each implant...... surrounded by a concentric 3 mm gap. These gaps were randomly allocated to four different procedures in each dog: 1) bone allograft used on its own; 2) ProOsteon used on its own; 3) allograft and ProOsteon used together; or 4) allograft and ProOsteon with the addition of osteogenic protein-1. After three...

  7. Multiple Rib Nonunion: Open Reduction and Internal Fixation and Iliac Crest Bone Graft Aspirate.

    Science.gov (United States)

    Kaplan, Daniel J; Begly, John; Tejwani, Nirmal

    2017-08-01

    Rib fractures are a common chest injury that can typically be treated nonoperatively. However, a percentage of these will go on to nonunion, either because of unique characteristics of the fracture itself or because of a variety of poor healing factors of the host. If a patient has continued symptomology beyond 3 months, surgeons may consider operative management. Although isolated resection of fibrous scar tissue from the nonunion site may be sufficient in some cases, it may also be necessary to provide additional structural integrity to the rib depending on the extent of the fracture pattern and resection. This goal can be achieved operatively with rib plating and bone grafting to promote healing. This video demonstrates the use of plating in the treatment of rib nonunion. It begins with relevant background information on rib fractures and nonunions, then details the approach, open reduction and internal fixation of 3 ribs using plates and bone graft aspirate. Pearls and pitfalls are included during the surgical technique aspect of the video to both help guide surgeons new to the procedure and provide potentially advantageous technical details to more experienced surgeons.

  8. 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. © 2012 Blackwell Verlag GmbH.

  9. 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. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.

  10. [Treatment of calcaneal fractures by fixation of Kirschner needle and thread cancellous bone screw through sinus tarsi interstice].

    Science.gov (United States)

    Lin, Cong-Xiang; Shi, Zheng-Yang; Xu, Yi-Min; Yang, Meng; Wang, Jia-Lin; Chen, Xiao-Jian; Zhang, Wei; Zhi, Shao-Xin

    2014-07-01

    To explore the effect of fixation of Kirschner needle and thread cancellous bone screw through the sinus tarsi interstice for the treatment of calcaneal fractures. From January 2009 to December 2012,20 patients with calcaneal fracture were treated by minimally invasive Kirschner wire and threaded cancellous bone screw fixation and bone graft,including 12 males and 8 females with an average age of 39 years old ranging from 21 to 65. Among them, 8 cases were left foot, 12 were right foot. According to Sanders's classification, 8 cases were type II, 10 cases were type III, 2 cases were type IV. All patients were followed up from 6 to 16 months with an average of 12 months. The incision were healed. Böhler angle were increased from preoperative (17.75 +/- 4.22) degrees to postoperative (26.85 +/- 7.37) degrees (t = 4.308, P = 0.000). Gissane angle were reduced from preoperative (137.05 +/- 24.91) degrees to postoperative (113.75 +/- 13.17) degrees (t = 7.083, P = 0.000). At 3 months after operation, the scores of AOFAS were 85.50 +/- 7.99; the results were excellent in 5 feet and good in 11 feet, fair in 3 feet, and poor in 1 foot. Minimally invasive fixation of Kirschner needle and thread cancellous bone screw fixation is a simple operation, it can get reliable fixation, easy to remove, low cost, less postoperative complications, and it is a good treatment of calcaneal fracture.

  11. Cortical bone trajectory for lumbosacral fixation: penetrating S-1 endplate screw technique: technical note.

    Science.gov (United States)

    Matsukawa, Keitaro; Yato, Yoshiyuki; Kato, Takashi; Imabayashi, Hideaki; Asazuma, Takashi; Nemoto, Koichi

    2014-08-01

    A cortical bone trajectory (CBT) is a new pedicle screw trajectory that maximizes the thread contact with cortical bone surface, providing enhanced screw purchase. Despite the increased use of the CBT in the lumbar spine, little is known about the insertion technique for the sacral CBT. The aim of this study was to introduce a novel sacral pedicle screw trajectory. This trajectory engages with denser bone maximally by the screw penetrating the S-1 superior endplate through a more medial entry point than the traditional technique, and also has safety advantages, with the protrusion of the screw tip into the intervertebral disc space carrying no risk of neurovascular injury. In this study, the CT scans of 50 adults were studied for morphometric measurement of the new trajectory. The entry point was supposed to be the junction of the center of the superior articular process of S-1 and approximately 3 mm inferior to the most inferior border of the inferior articular process of L-5. The direction was straight forward in the axial plane without convergence, angulated cranially in the sagittal plane penetrating the middle of the sacral endplate. The cephalad angle to the sacral endplate, length of trajectory, and safety of the trajectory were investigated. Next, the insertional torque of pedicle screws using this technique was measured intraoperatively in 19 patients and compared with the traditional technique. The mean cephalad angle in these 50 patients was 30.7° ± 5.1°, and the mean length of trajectory was 31.5 ± 3.5 mm. The CT analysis revealed that the penetrating S-1 endplate technique did not cause any neurovascular injury anteriorly in any case. The new technique demonstrated an average of 141% higher insertional torque than the traditional monocortical technique. The penetrating S-1 endplate technique through the medial entry point is suitable for the connection of lumbar CBT, has revealed favorable stability for lumbosacral fixation, and has reduced the

  12. Medial support by fibula bone graft in angular stable plate fixation of proximal humeral fractures: an in vitro study with synthetic bone.

    Science.gov (United States)

    Osterhoff, Georg; Baumgartner, Daniel; Favre, Philippe; Wanner, Guido A; Gerber, Hans; Simmen, Hans-Peter; Werner, Clément M L

    2011-07-01

    Failure to achieve stable fixation with medial support in proximal humeral fractures can result in varus malalignment and cut-through of the proximal screws. The purpose of this study was to investigate the influence of an intramedullary fibula bone graft on the biomechanical properties of proximal humeral fractures stabilized by angular stable plate fixation in a bone model under cyclic loading. Two fixation techniques were tested in 20 composite analog humeri models. In group F- (n = 10), fractures were fixed by an anatomically formed locking plate system. In group F+ (n = 10), the same fixation system was used with an additional fibular graft model with a length of 6 cm inserted in an intramedullary manner. Active abduction was simulated for 400 cycles by use of a recently established testing setup. Fragment gap distance was measured, and thereby, intercyclic motion, fragment migration, and residual plastic deformation were determined. The addition of a fibular graft to the fixation plate led to 5 times lower intercyclic motion, 2 times lower fragment migration, and 2 times less residual plastic deformation. Neither screw pullout, cut-through, nor implant failure was observed. Medial support with an intramedullary fibular graft in an angular stable fixation of the proximal humerus in vitro increases overall stiffness of the bone-implant construct and reduces migration of the humeral head fragment. This technique might provide a useful tool in the treatment of displaced proximal humeral fractures, especially when there is medial comminution. Copyright © 2011 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  13. Comparative study on fixation of central venous catheter by suture versus adhesive device.

    Science.gov (United States)

    Molina-Mazón, C S; Martín-Cerezo, X; Domene-Nieves de la Vega, G; Asensio-Flores, S; Adamuz-Tomás, J

    2018-03-27

    To assess the efficacy of a central venous catheter adhesive fixation device (CVC) to prevent associated complications. To establish the need for dressing changes, number of days' catheterization and reasons for catheter removal in both study groups. To assess the degree of satisfaction of personnel with the adhesive system. A, randomized, prospective and open pilot study, of parallel groups, with comparative evaluation between CVC fixation with suture and with an adhesive safety system. The study was performed in the Coronary Unit of the Universitari de Bellvitge Hospital, between April and November 2016. The population studied were patients with a CVC. The results were analyzed using SPSS Statistics software. The study was approved by the Clinical Research Ethics Committee. 100 patients (47 adhesive system and 53 suture) were analyzed. Both groups were homogeneous in terms of demographic variables, anticoagulation and days of catheterization. The frequency of complications in the adhesive system group was 21.3%, while in the suture group it was 47.2% (P=.01). The suture group had a higher frequency of local signs of infection (p=.006), catheter displacement (p=.005), and catheter-associated bacteraemia (P=.05). The use of adhesive fixation was associated with a lower requirement for dressing changes due to bleeding (P=.006). Ninety-six point seven percent of the staff recommended using the adhesive safety system. The catheters fixed with adhesive systems had fewer infectious complications and less displacement. Copyright © 2018 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.

  14. 2000 Volvo Award winner in biomechanical studies: Monitoring in vivo implant loads with a telemeterized internal spinal fixation device.

    Science.gov (United States)

    Rohlmann, A; Graichen, F; Weber, U; Bergmann, G

    2000-12-01

    Implant loads were measured in 10 patients using telemeterized internal spinal fixation devices. To determine the postoperative temporal course of implant loads. Little information exists regarding the temporal course of loads on internal spinal fixation devices. The telemeterized internal spinal fixator allows the measurement of three force components and three moments acting in the fixator. Implant loads were determined in up to 20 measuring sessions for different activities, including walking, standing, sitting, lying in the supine position, and lifting an extended leg while in the supine position. Implant loads often increased shortly after anterior interbody fusion was performed. Several patients retained the same high level even after fusion had taken place. This explains the reason why screw breakage sometimes occurs more than half a year after implantation. The time of fusion could not be pinpointed from the loading curves. The results show that fixators may be highly loaded even after fusion has occurred. A flexion bending moment acts on the implant even with the body in a relaxed lying position. This means that already shortly after the anterior procedure, the shape of the spine is not neutral and unloaded, but slightly deformed, which loads the fixators. Pedicle screw breakage more than half a year after insertion does not prove that anterior interbody fusion has not occurred.

  15. A Biomechanical Analysis of Interference Screw Versus Bone Tunnel Fixation of Flexor Hallucis Longus Tendon Transfers to the Calcaneus.

    Science.gov (United States)

    Liu, George T; Balldin, B Christian; Zide, Jacob R; Chen, Christopher T

    The flexor hallucis longus tendon transfer is commonly used to restore function in chronic Achilles tendon ruptures and chronic Achilles tendinopathy. The tendon is often secured to the calcaneus either through a bone tunnel or by an interference screw. We hypothesized that tenodesis using the bone tunnel method would be mechanically superior to interference screw fixation for flexor hallucis longus transfers. Eight matched pairs of cadaveric specimens were assigned randomly to the bone tunnel or interference screw technique and were loaded to failure. Biomechanical analysis was performed to evaluate the ultimate strength, peak stress, Young's modulus, failure strain, and strain energy. Unpaired comparison, paired comparison, and linear regression analyses were used to determine statistical significance. A slight 22% ± 9% decrease in Young's modulus and a 52% ± 18% increase of strain energy were found in the interference screw group. However, no differences in ultimate strength, peak stress, or failure strain were seen between the 2 groups on paired comparison. Our findings suggest that interference screw fixation provides similar spontaneous biomechanical properties to the use of a bone tunnel for flexor hallucis longus transfer to the calcaneus. The interference screw is a practical option for fixation of the flexor hallucis longus tendon to the calcaneus and can be performed through a single incision approach. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  16. [Effectiveness of U-shape titanium screw-rod fixation system with bone autografting for lumbar spondylolysis of young adults].

    Science.gov (United States)

    Pu, Xiaobing; Yang, Shuangshi; Cao, Haiquan; Jing, Xingquan; Yin, Jun

    2014-03-01

    To investigate the effectiveness of U-shape titanium screw-rod fixation system with bone autografting for lumbar spondylolysis of young adults. Between January 2008 and December 2011, 32 patients with lumbar spondylolysis underwent U-shape titanium screw-rod fixation system with bone autografting. All patients were male with an average age of 22 years (range, 19-32 years). The disease duration ranged from 3 to 24 months (mean, 14 months). L3 was involved in spondylolysis in 2 cases, L4 in 10 cases, and L5 in 20 cases. The preoperative visual analogue scale (VAS) and Oswestry disability index (ODI) scores were 8.0 +/- 1.1 and 75.3 +/- 11.2, respectively. The operation time was 80-120 minutes (mean, 85 minutes), and the blood loss was 150-250 mL (mean, 210 mL). Primary healing of incision was obtained in all patients without complications of infection and nerve symptom. Thirty-two patients were followed up 12-24 months (mean, 14 months). Low back pain was significantly alleviated after operation. The VAS and ODI scores at 3 months after operation were 1.0 +/- 0.5 and 17.6 +/- 3.4, respectively, showing significant differences when compared with preoperative ones (t = 30.523, P = 0.000; t = 45.312, P = 0.000). X-ray films and CT showed bone fusion in the area of isthmus defects, with the bone fusion time of 6-12 months (mean, 9 months). During follow-up, no secondary lumbar spondyloly, adjacent segment degeneration, or loosening or breaking of internal fixator was found. The U-shape titanium screw-rod fixation system with bone autografting is a reliable treatment for lumbar spondylolysis of young adults because of a high fusion rate, minimal invasive, and maximum retention of lumbar range of motion.

  17. In Vitro Evaluation of Inflow Cannula Fixation Techniques in Left Ventricular Assist Device Surgery.

    Science.gov (United States)

    Hanke, Jasmin S; Krabatsch, Thomas; Rojas, Sebastian V; Deniz, Ezin; Ismail, Issam; Martens, Andreas; Shrestha, Malakh; Haverich, Axel; Netuka, Ivan; Schmitto, Jan D

    2017-03-01

    The therapy of terminal heart failure with left ventricular assist devices has become a standard in cardiac surgery. Yet the surgical implantation technique is not standardized and differs from center to center. Complications associated with left ventricular assist device (LVAD) inflow cannula placement are thrombosis, suction events, and flow disturbances. Within this in vitro study we aimed to investigate if the fixation technique of the sewing ring has an impact on the position of the inflow cannula. For this in vitro study the HeartMate III LVAD (Thoratec Corporation, Pleasanton, CA, USA) was used. In five sessions, two approaches were considered for coring of the ventricle for LVAD inflow cannula insertion: "sew-then-core" and "core-then-sew." In the "sew-then-core" technique, the sewing cuff is first affixed to the heart, usually with 8-16 interrupted pledgeted mattress sutures. Subsequently, a cylindrical knife is used to resect a cylindrical core of myocardium to permit cannula insertion. In the "core-then-sew" technique, the sequence is reversed such that the knife is used before the suture ring is affixed. When the "sew-then-core" technique is used, the mattress sutures may be placed with full-thickness bites that penetrate the endocardium (i.e., transmural stitching) or partial-thickness bites that do not penetrate the endocardium (i.e., epicardial stitching). When the "core-then-sew" technique is used, the suture is passed fully into the ventricular lumen and fed back through the cored hole, at which point the needle may be reinserted into the freshly cored myocardium such that it exits the epicardium (i.e., transmural stitching with back stitch) or not (i.e., transmural stitching without back stitch). These four different sewing ring fixation suturing techniques were tested by experienced surgeons to affix the sewing ring: transmural stitching, epicardial stitching, transmural stitching with back stitch, and transmural stitching without back stitch

  18. Orthopedic infections in equine long bone fractures and arthrodeses treated by internal fixation: 192 cases (1990-2006).

    Science.gov (United States)

    Ahern, Benjamin J; Richardson, Dean W; Boston, Raymond C; Schaer, Thomas P

    2010-07-01

    To determine the rate of postoperative infection (POI) for internal fixation repaired equine long bone fractures and arthrodeses and identify associated risk factors. Case series. Horses (n=192) with fracture repair of the third metacarpal and metatarsal bones, radius, ulna, humerus, tibia, and femur, or arthrodesis with internal fixation. Medical records (1990-2006) were reviewed for signalment, anatomic location, fracture classification and method of repair, technique and surgical duration, bacterial species isolated, postoperative care, onset of POI, and outcome. Of 192 horses (171 [89%] closed, 21 [11%] open fractures), 157 (82%) were discharged from the hospital. Infection occurred in 53 (28% horses), of which 31 (59%) were discharged. Repairs without POI were 7.25 times more likely to be discharged from the hospital. Closed fractures were 4.23 times more likely to remain uninfected and 4.59 times more likely to be discharged from the hospital compared with open fractures. Closed reduction and internal fixation was associated with a 2.5-fold reduction in rate of POI and a 5.9 times greater chance for discharge from the hospital compared with open reduction and internal fixation. Females had a strong trend for increased POI when compared with colts and stallion but not geldings. Overall rate of POI was 28%. Fracture classification, method of repair, gender, and surgical duration were significant risk factors.

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

    Science.gov (United States)

    Boero, Emanuele; Mogollo, Maria del Amparo Paredes

    2015-12-01

    A 20-year-old man was admitted to our hospital having sustianed bilateral high-energy femoral fractures. The right femoral fracture was an open grade 3B with OTA grade 3 bone loss. The patient had also a brain contusion with a subdural haematoma and a closed fracture of the left clavicle. Initial management included temporarily stabilisation of the femoral fractures wth external fixators and prompt transfer to the intensive care unit. Three weeks later the external fixator of the right femur was converted to an hybrid system, and the fixator of the left side was removed and a reamed intramedullary locking nail was applied. Two months after the accident the patient underwent bone transport (11 cm long) of the right femur with an monolateral external fixation. When the final length was achieved there were knee stiffness (ROM 0° to 30°) and non-union of the docking site. Therefore, the patient underwent a Judet's procedure to treat the knee stiffness and stabilisation of the non united femur with a locking plate (LISS). After the operation the patient started progressive weight bearing. A year after trauma and following union of the femur, the patient underwent soft tissue reconstruction of the anterior side of the thigh with a free vascularised flap. At final follow upo the patient had a good functional recovery with return to his previous occupation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Animal Models for Evaluation of Bone Implants and Devices: Comparative Bone Structure and Common Model Uses.

    Science.gov (United States)

    Wancket, L M

    2015-09-01

    Bone implants and devices are a rapidly growing field within biomedical research, and implants have the potential to significantly improve human and animal health. Animal models play a key role in initial product development and are important components of nonclinical data included in applications for regulatory approval. Pathologists are increasingly being asked to evaluate these models at the initial developmental and nonclinical biocompatibility testing stages, and it is important to understand the relative merits and deficiencies of various species when evaluating a new material or device. This article summarizes characteristics of the most commonly used species in studies of bone implant materials, including detailed information about the relevance of a particular model to human bone physiology and pathology. Species reviewed include mice, rats, rabbits, guinea pigs, dogs, sheep, goats, and nonhuman primates. Ultimately, a comprehensive understanding of the benefits and limitations of different model species will aid in rigorously evaluating a novel bone implant material or device. © The Author(s) 2015.

  1. Comparison of external fixation versus the trauma pelvic orthotic device on unstable pelvic injuries: a cadaveric study of stability.

    Science.gov (United States)

    Prasarn, Mark L; Horodyski, MaryBeth; Conrad, Bryan; Rubery, Paul T; Dubose, Dewayne; Small, John; Rechtine, Glenn R

    2012-06-01

    Most institutions treating pelvic fractures use some method of acute mechanical stabilization. This typically involves use of pelvic binders or circumferential sheeting, and/or external fixation. The comparative value of these different modalities is controversial. We hypothesized that an external fixator would provide more stability to an unstable pelvic injury than a commercially available binder device (trauma pelvic orthotic device [T-POD]). Unstable pelvic injuries (Tile C) were surgically created in five fresh whole human cadavers. Electromagnetic sensors were placed on the same position of each hemipelvis. The amount of angular motion during testing was measured using a Fastrak, three-dimensional, electromagnetic motion analysis device. Maximum displacements were recorded during application of the stabilizing devices, bed transfer, logrolling, and head-of-bed elevation. External fixation frames were constructed by placing two 5.0-mm half pins into the iliac crest and then connected them with a 10-mm curved bar. The T-POD device was placed at the level of the greater trochanters as per manufacturer's recommendations. While logrolling the patient and performing bed transfers, the T-POD conferred more stability in all planes of motion, although this did not reach statistical significance. During elevation of the head of the bed, the T-POD allowed less motion in the sagittal and coronal planes but permitted equivalent motion in axial rotation. These differences were not statistically significant. There were no significant differences in stability conferred by an external fixator or a T-POD for unstable pelvic injuries. We advocate acute, temporary stabilization of pelvic injuries with a binder device and early conversion to internal fixation when the patient's medical condition allows. Copyright © 2012 by Lippincott Williams & Wilkins.

  2. Finite element analysis of a bone healing model: 1-year follow-up after internal fixation surgery for femoral fracture.

    Science.gov (United States)

    Jiang-Jun, Zhou; Min, Zhao; Ya-Bo, Yan; Wei, Lei; Ren-Fa, Lv; Zhi-Yu, Zhu; Rong-Jian, Chen; Wei-Tao, Yu; Cheng-Fei, Du

    2014-03-01

    Finite element analysis was used to compare preoperative and postoperative stress distribution of a bone healing model of femur fracture, to identify whether broken ends of fractured bone would break or not after fixation dislodgement one year after intramedullary nailing. Method s: Using fast, personalized imaging, bone healing models of femur fracture were constructed based on data from multi-slice spiral computed tomography using Mimics, Geomagic Studio, and Abaqus software packages. The intramedullary pin was removed by Boolean operations before fixation was dislodged. Loads were applied on each model to simulate a person standing on one leg. The von Mises stress distribution, maximum stress, and its location was observed. Results : According to 10 kinds of display groups based on material assignment, the nodes of maximum and minimum von Mises stress were the same before and after dislodgement, and all nodes of maximum von Mises stress were outside the fracture line. The maximum von Mises stress node was situated at the bottom quarter of the femur. The von Mises stress distribution was identical before and after surgery. Conclusion : Fast, personalized model establishment can simulate fixation dislodgement before operation, and personalized finite element analysis was performed to successfully predict whether nail dislodgement would disrupt femur fracture or not.

  3. Treatment of Atypical Ulnar Fractures Associated with Long-Term Bisphosphonate Therapy for Osteoporosis: Autogenous Bone Graft with Internal Fixation

    Directory of Open Access Journals (Sweden)

    Yohei Shimada

    2017-01-01

    Full Text Available Long-term bisphosphonate use has been suggested to result in decreased bone remodelling and an increased risk of atypical fractures. Fractures of this nature commonly occur in the femur, and relatively few reports exist to show that they occur in other bones. Among eight previous reports of atypical ulnar fractures associated with bisphosphonate use, one report described nonunion in a patient who was treated with cast immobilization and another described ulna nonunion in one of three patients, all of whom were treated surgically with a locking plate. The remaining two surgical patients achieved bone union uneventfully following resection of the osteosclerotic lesion and iliac bone grafting before rigid fixation. We hypothesized that the discontinuation of bisphosphonate therapy, the use of teriparatide treatment, and low-intensity pulsed ultrasound (LIPUS might have been associated with fracture healing.

  4. In vitro biomechanical properties of 2 compression fixation methods for midbody proximal sesamoid bone fractures in horses.

    Science.gov (United States)

    Woodie, J B; Ruggles, A J; Litsky, A S

    2000-01-01

    To evaluate 2 methods of midbody proximal sesamoid bone repair--fixation by a screw placed in lag fashion and circumferential wire fixation--by comparing yield load and the adjacent soft-tissue strain during monotonic loading. Experimental study. 10 paired equine cadaver forelimbs from race-trained horses. A transverse midbody osteotomy of the medial proximal sesamoid bone (PSB) was created. The osteotomy was repaired with a 4.5-mm cortex bone screw placed in lag fashion or a 1.25-mm circumferential wire. The limbs were instrumented with differential variable reluctance transducers placed in the suspensory apparatus and distal sesamoidean ligaments. The limbs were tested in axial compression in a single cycle until failure. The cortex bone screw repairs had a mean yield load of 2,908.2 N; 1 limb did not fail when tested to 5,000 N. All circumferential wire repairs failed with a mean yield load of 3,406.3 N. There was no statistical difference in mean yield load between the 2 repair methods. The maximum strain generated in the soft tissues attached to the proximal sesamoid bones was not significantly different between repair groups. All repaired limbs were able to withstand loads equal to those reportedly applied to the suspensory apparatus in vivo during walking. Each repair technique should have adequate yield strength for repair of midbody fractures of the PSB immediately after surgery.

  5. Central tarsal bone fractures in horses not used for racing: Computed tomographic configuration and long-term outcome of lag screw fixation

    OpenAIRE

    Gunst, S; Del Chicca, Francesca; Fürst, Anton; Kuemmerle, Jan M

    2016-01-01

    REASONS FOR PERFORMING STUDY: There are no reports on the configuration of equine central tarsal bone fractures based on cross-sectional imaging and clinical and radiographic long-term outcome after internal fixation. OBJECTIVES: To report clinical, radiographic and computed tomographic findings of equine central tarsal bone fractures and to evaluate the long-term outcome of internal fixation. STUDY DESIGN: Retrospective case series. METHODS: All horses diagnosed with a central tarsa...

  6. 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.

    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

  7. A systematic quality assurance study in bone densitometry devices

    Science.gov (United States)

    Tuncman, Duygu; Kovan, Hatice; Kovan, Bilal; Demir, Bayram; Turkmen, Cuneyt

    2015-07-01

    Osteoporosis is the most common metabolic bone disease and can result in devastating physical, psychosocial, and economic consequences. It occurs in women after menopause and affects most elderly. Dual-energy x-ray absorptiometry (DXA) is currently the most widely used method for the measurement of areal Bone Mineral Density (BMD) (g/cm2) .DXA is based on the variable absorption of X-ray by the different body components and uses high and low energy X-ray photons. There are two important values in the assessment of the DXA. These values are T-score and Z-score. The T-score is calculated by taking the difference between a patient's measured BMD with the mean BMD of the young normal population, matched for gender and ethnicity, and then by dividing the difference with the standard deviation (SD) of the BMD of the young normal population. T-score and also Z-score are directly depends on the Bone Mineral Density (BMD). BMD measurements should be made periodically in a patient life. But mostly, it is not possible with the same device. Therefore, in this study, for the quality assurance of bone densitometry devices, we evaluated the BMD results measured in the different Bone Densitometry (DXA) devices using a spine phantom.

  8. Percutaneous, Transtrapezial Fixation without Bone Graft Leads to Consolidation in Selected Cases of Delayed Union of the Scaphoid Waist.

    Science.gov (United States)

    Vanhees, Matthias; van Riet, Roger R P; van Haver, Annemieke; Kebrle, Radek; Meermans, Geert; Verstreken, Frederik

    2017-08-01

    Purpose  We evaluated clinical and radiographic outcome of percutaneous transtrapezial fixation of the scaphoid delayed union or nonunion using a headless bone screw without bone grafting. Methods  Sixteen patients with delayed union or nonunion of the scaphoid were included in this retrospective study between 2006 and 2011. All patients had a delayed presentation of scaphoid fracture, and none of them was treated conservatively elsewhere. Patients with bone graft, sclerotic bone debridement, or displacement of the fragment at the nonunion site were excluded. A percutaneous transtrapezial fixation technique was used in all cases. Patients were reviewed until clinical and radiographic union was observed. At the final follow-up, DASH (Disabilities of the Arm, Shoulder and Hand) and PRWHE (Patient-Rated Wrist and Hand Evaluation) outcome scores were completed. Results  Radiographic union was obtained in 15 out of 16 patients (94%) at an average follow-up of 36 months (range: 12-98 months). No complications from the percutaneous technique were noted. The average DASH score was 6 (range: 0-39) and the average PRWHE score was 10 (range: 0-56). No statistical significant difference in range of motion and grip strength was found between the operated side and the contralateral side. Conclusion  Percutaneous transtrapezial screw fixation for delayed or nonunion of selected scaphoid fractures without bone grafting is promising. At a mean of 4 months, 94% union was obtained with good functional results when there was no sclerosis, minimal osteolysis, and no displacement at the scaphoid nonunion site. Type of Study  Therapeutic study. Level of Evidence  IV.

  9. 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. © 2014 Wiley Periodicals, Inc.

  10. Modified tension band wiring fixation for avulsion fractures of the calcaneus in osteoporotic bone: a review of three patients.

    Science.gov (United States)

    Nagura, Issei; Fujioka, Hiroyuki; Kurosaka, Masahiro; Mori, Hiroyuki; Mitani, Makoto; Ozaki, Akihiro; Fujii, Hideo; Nabeshima, Yuji

    2012-01-01

    Calcaneal avulsion fractures are not uncommon, and they are probably more likely in patients with osteoporosis. Closed manipulation for this type of fracture often fails to achieve acceptable reduction, and open reduction and internal fixation are usually required. However, open reduction and internal fixation with either a lag screw or Steinmann pins do not provide satisfactory fixation in patients with diabetes and elderly patients because of the presence of porotic bone. Levi described a tension band fixation system used to treat a calcaneal avulsion fracture using a simple technique performed with a transverse Kirschner wire through the os calcaneus, securing a figure-of-8 metal tension band wiring to the fragment. We report the successful treatment of 3 patients with calcaneal avulsion fractures using a modified tension band wiring technique, resulting in satisfactory recovery. Re-displacement of the fragment during the initial follow-up period was not reported, and bony union was achieved in all patients. We believe this technique is a useful surgical option for the treatment of calcaneal avulsion fractures. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    Giacomo, Giovanni Di; Costantini, Alberto; de Gasperis, Nicola; De Vita, Andrea; Lin, Bernard K. H.; Francone, Marco; Beccaglia, Mario A. Rojas; Mastantuono, Marco

    2013-01-01

    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 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. PMID:23858288

  12. Biomechanical analysis of an interference screw and a novel twist lock screw design for bone graft fixation.

    Science.gov (United States)

    Asnis, S; Mullen, J; Asnis, P D; Sgaglione, N; LaPorta, T; Grande, D A; Chahine, N O

    2017-12-01

    Malpositioning of an anterior cruciate ligament graft during reconstruction can occur during screw fixation. The purpose of this study is to compare the fixation biomechanics of a conventional interference screw with a novel Twist Lock Screw, a rectangular shaped locking screw that is designed to address limitations of graft positioning and tensioning. Synthetic bone (10, 15, 20lb per cubic foot) were used simulating soft, moderate, and dense cancellous bone. Screw push-out and graft push-out tests were performed using conventional and twist lock screws. Maximum load and torque of insertion were measured. Max load measured in screw push out with twist lock screw was 64%, 60%, 57% of that measured with conventional screw in soft, moderate and dense material, respectively. Twist lock max load was 78% and 82% of that with conventional screw in soft and moderate densities. In the highest bone density, max loads were comparable in the two systems. Torque of insertion with twist lock was significantly lower than with conventional interference screw. Based on geometric consideration, the twist lock screw is expected to have 35% the holding power of a cylindrical screw. Yet, results indicate that holding power was greater than theoretical consideration, possibly due to lower friction and lower preloaded force. During graft push out in the densest material, comparable max loads were achieved with both systems, suggesting that fixation of higher density bone, which is observed in young athletes that require reconstruction, can be achieved with the twist lock screw. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Bone age maturity assessment using hand-held device

    Science.gov (United States)

    Ratib, Osman M.; Gilsanz, Vicente; Liu, Xiaodong; Boechat, M. I.

    2004-04-01

    Purpose: Assessment of bone maturity is traditionally performed through visual comparison of hand and wrist radiograph with existing reference images in textbooks. Our goal was to develop a digital index based on idealized hand Xray images that can be incorporated in a hand held computer and used for visual assessment of bone age for patients. Material and methods: Due to the large variability in bone maturation in normals, we generated a set of "ideal" images obtained by computer combinations of images from our normal reference data sets. Software for hand-held PDA devices was developed for easy navigation through the set of images and visual selection of matching images. A formula based on our statistical analysis provides the standard deviation from normal based on the chronological age of the patient. The accuracy of the program was compared to traditional interpretation by two radiologists in a double blind reading of 200 normal Caucasian children (100 boys, 100 girls). Results: Strong correlations were present between chronological age and bone age (r > 0.9) with no statistical difference between the digital and traditional assessment methods. Determinations of carpal bone maturity in adolescents was slightly more accurate using the digital system. The users did praise the convenience and effectiveness of the digital Palm Index in clinical practice. Conclusion: An idealized digital Palm Bone Age Index provides a convenient and effective alternative to conventional atlases for the assessment of skeletal maturity.

  14. 21 CFR 888.3045 - Resorbable calcium salt bone void filler device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Resorbable calcium salt bone void filler device. 888.3045 Section 888.3045 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... salt bone void filler device. (a) Identification. A resorbable calcium salt bone void filler device is...

  15. The Benefits of Cement Augmentation of Pedicle Screw Fixation Are Increased in Osteoporotic Bone: A Finite Element Analysis.

    Science.gov (United States)

    Wang, Wenhai; Baran, George R; Garg, Hitesh; Betz, Randal R; Moumene, Missoum; Cahill, Patrick J

    2014-07-01

    Biomechanical study using a finite element model of a normal and osteoporotic lumbar vertebrae comparing resistance with axial pullout and bending forces on polymethylmethacrylate-augmented and non-augmented pedicle screws. To compare the effect of cement augmentation of pedicle screw fixation in normal and osteoporotic bone with 2 different techniques of cement delivery. Various clinical and biomechanical studies have addressed the benefits of cement augmentation of pedicle screws, but none have evaluated whether this effect is similar, magnified, or attenuated in osteoporotic bone compared with normal bone. In addition, no study has compared the biomechanical strength of augmented pedicle screws using cement delivery through the pedicle screw with delivery through a pilot hole. This study was funded by a grant from DePuy Synthes Spine. Normal and osteoporotic lumbar vertebrae with pedicle screws were simulated. The models were tested for screw pullout strength with and without cement augmentation. Two methods of cement delivery were also tested. Both methods were tested using 1 and 2.5 cm 3 volume of cement infiltrated in normal and osteoporotic bone. The increase in screw pullout force was proportionally greater in osteoporotic bone with equivalent volumes of cement delivered. The researchers found that 1 and 2.5 cm 3 of cement infiltrated bone volume resulted in an increase in pullout force by about 50% and 120% in normal bone, and by about 64% and 156% in osteoporotic bone, respectively. The delivery method had only a minimal effect on pullout force when 2.5 cm 3 of cement was injected (strength of pedicle screws, and this effect is proportionately greater in osteoporotic bone. Cement delivery through fenestrated screws and delivery through a pilot hole result in comparable pullout strength at higher cement volumes. Copyright © 2014 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

  16. Bone-anchored hearing device placement with translabyrinthine tumor removal.

    Science.gov (United States)

    McRackan, Theodore R; Goddard, John C; Wilkinson, Eric P; Slattery, William H; Brackmann, Derald E

    2015-02-01

    Translabyrinthine resection of intracranial tumors results in single-sided deafness, which can be treated by surgical and nonsurgical means. Here we describe the first series examining complication and device usage rates among patients receiving a surgically implanted bone-anchored hearing device (BAHD) at the time of translabyrinthine tumor removal. Case series with chart review. Private tertiary neurotologic referral center. Patients (N = 154) undergoing concurrent BAHD placement and translabyrinthine tumor resection. Concurrent BAHD placement and translabyrinthine tumor removal. Postoperative complication rates and BAHD usage. Of the 154 patients, 121 (78.6%) had no device-related complications. The most common device-related complications were skin overgrowth (8.4%), acute infection (5.2%), and chronic infection (3.2%). The overall and specific complication rates did not differ from published BAHD complication rates. One patient (0.6%) developed a cerebrospinal leak through the surgical site for the device. At the time of last follow-up (mean, 39.8 months), 151 patients (95.0%) were still using their devices. Patients undergoing concurrent translabyrinthine tumor removal and BAHD placement exhibit similar device-related complication profiles as patients undergoing standard device placement. Based on these outcomes and the high long-term usage rates, BAHD insertion at the time of translabyrinthine intracranial surgery can be considered a safe and useful procedure. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  17. Comparison of Cemented and Bone Ingrowth Fixation Methods in Hip Resurfacing for Osteonecrosis.

    Science.gov (United States)

    O'Leary, Ryan J; Gaillard, Melissa D; Gross, Thomas P

    2017-02-01

    The optimal surgical treatment for osteonecrosis of the femoral head has yet to be elucidated. To evaluate the role of femoral fixation techniques in hip resurfacing, we present a comparison of the results for 2 consecutive groups: group 1 (75 hips) received hybrid hip resurfacing implants with a cemented femoral component; group 2 (103 hips) received uncemented femoral components. Both groups received uncemented acetabular components. We retrospectively analyzed our clinical database to compare failures, reoperations, complications, clinical results, metal ion test results, and X-ray measurements. Using consecutive groups caused time interval bias, so we required all group 2 patients to be at least 2 years out from surgery; we compared results from 2 years and final follow-up. Patient groups matched similarly in age, body mass index, and percent female. Despite similar demographics, the uncemented, group 2 cases showed a lower raw failure rate (0% vs 16%; P < .0001), a lower 2-year failure rate (0% vs 7%; P = .04), and a superior 8-year implant survivorship (100% vs 91%; log-rank P = .0028; Wilcoxon P = .0026). In cases that did not fail, patient clinical (P = .05), activity (P = .02), and pain scores (P = .03), as well as acetabular component position (P < .0001), all improved in group 2, suggesting advancements in surgical management. There were no cases of adverse wear-related failure in either group. This study demonstrates a superior outcome for cases of osteonecrosis with uncemented hip resurfacings compared to cases employing hybrid devices. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  18. Temporary arthrodesis using fixator rods in two-stage revision of septic knee prothesis with severe bone and tissue defects.

    Science.gov (United States)

    Röhner, Eric; Pfitzner, Tilman; Preininger, Bernd; Zippelius, Timo; Perka, Carsten

    2016-01-01

    The present study describes a new temporary arthrodesis procedure, which aims for septic knee prosthesis replacement, in particular for larger bone and soft tissue defects. Our technique offers high stability and full weight-bearing capacity of the knee joint. The study included 16 patients with major bone defects (AORI type IIb or greater) after receiving a radical debridement and a septic two-stage revision total knee arthroplasty. After removing the infected prosthesis and debridement, two AO fixator rods were positioned into the intramedullary space of the femur and tibia. Subsequently, both rods were joined tube-to-tube and adjusted in the center of the knee joint. Finally, the whole cavity of the knee joint was filled with PMMA. The number of previous surgeries, bacterial spectrum, risk factors for further infection and reinfection rates was recorded. Immediately after the temporary arthrodesis, radiographs of the knee with the enclosed spacers were taken in order to compare to previous radiographs and avoiding to miss possible spacer loosening. Nine of sixteen patients underwent more than two revision surgeries before receiving our new arthrodesis technique. No cases of spacer loosening were observed in all 16 patients; further, there were no peri-implant fractures, and four persistent infections were noted. Temporary arthrodesis using AO fixator rods offers a high stability without loosening. Its potential to replace conventional augmentation techniques should be taken into account, particularly in the case of larger bone and tissue defects. In clinical practice, the cemented spacer using AO fixator rods could be an alternative technique for temporary knee arthrodesis after septic debridement. Retrospective case series, Level IV.

  19. Intramedullary screw fixation with bone autografting to treat proximal fifth metatarsal metaphyseal-diaphyseal fracture in athletes: a case series

    Directory of Open Access Journals (Sweden)

    Tsukada Sachiyuki

    2012-07-01

    Full Text Available Abstract Background Delayed unions or refractures are not rare following surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fractures. Intramedullary screw fixation with bone autografting has the potential to resolve the issue. The purpose of this study was to evaluate the result of the procedure. Methods The authors retrospectively reviewed 15 athletes who underwent surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fracture. Surgery involved intramedullary cannulated cancellous screw fixation after curettage of the fracture site, followed by bone autografting. Postoperatively, patients remain non weight-bearing in a splint or cast for two weeks and without immobilization for an additional two weeks. Full weight-bearing was allowed six weeks postoperatively. Running was permitted after radiographic bone union, and return-to-play was approved after gradually increasing the intensity. Results All patients returned to their previous level of athletic competition. Mean times to bone union, initiation of running, and return-to-play were 8.4, 8.8, and 12.1 weeks, respectively. Although no delayed unions or refractures was observed, distal diaphyseal stress fractures at the distal tip of the screw occurred in two patients and a thermal necrosis of skin occurred in one patient. Conclusions There were no delayed unions or refractures among patients after carrying out a procedure in which bone grafts were routinely performed, combined with adequate periods of immobilization and non weight-bearing. These findings suggest that this procedure may be useful option for athletes to assuring return to competition level.

  20. 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.

  1. Plate fixation and bone grafting of distal clavicle nonunions: radiologic and functional outcomes

    NARCIS (Netherlands)

    Villa, Jordan C.; van der List, Jelle P.; Gausden, Elizabeth B.; Lorich, Dean G.; Helfet, David L.; Kloen, Peter; Wellman, David S.

    2016-01-01

    The optimal treatment for distal clavicle nonunions remains unknown. Small series have reported outcomes following distal fragment excision and various fixation techniques. We present the clinical, radiographic and functional outcomes after superior plating or double (superior and anteroinferior)

  2. Evaluation of bone thickness around the mental foramen for potential fixation of a bone-borne functional appliance: a computer tomography scan study.

    Science.gov (United States)

    Al-Kalaly, Abdullah A; Wong, Ricky W K; Cheung, Lim K; Purkayastha, Shimanto K; Schätzle, Marc; Rabie, A Bakr M

    2010-11-01

    A mandible bone-borne Herbst appliance (MBBHA) would avoid the proclination of the lower incisors that occurs with any teeth-borne functional appliance. But mapping of the bone characteristics at potential fixation areas around the mental foramen has not been carried out so far. The aim of this computer tomographic (CT) study was to evaluate bone thickness at specific positions around the mental foramen. CT scans of 60 randomly chosen adult Hong Kong Chinese subjects (mean age 28 ± 6.3 years) were used to measure the bi-cortical bone thickness in the mandible in the mental foramen area. The thickness of buccal and lingual cortical and cancellous bone was assessed at the following locations: 10 mm (A10 mm) and 5 mm (A5 mm) anterior, 10 mm (P10 mm) and 5 mm (P5 mm) posterior, and 5 mm (Inf5 mm) below the mental foramen. The amount of buccal cortical bone thickness ranged between 1.89 mm, 10 mm anterior of the mental foramen, and 2.16 mm, 10 mm posterior to its location. At the A10 mm level, cortical thickness showed a marginal statistically significant difference between A5 and A10 mm. The total amount of bone thickness ranged from 10.19 to 12.06 mm. At the locations studied around the mental foramen, a mean bicortical bone thickness of 10-12 mm was measured. No large variation in the thickness was found between bicortical bone thicknesses in the measured locations around the mental foramen. Thorough evaluation on a case-by-case basis is advisable. © 2010 John Wiley & Sons A/S.

  3. A new bone surrogate model for testing interbody device subsidence.

    Science.gov (United States)

    Au, Anthony G; Aiyangar, Ameet K; Anderson, Paul A; Ploeg, Heidi-Lynn

    2011-07-15

    An in vitro biomechanical study investigating interbody device subsidence measures in synthetic vertebrae, polyurethane foam blocks, and human cadaveric vertebrae. To compare subsidence measures of bone surrogates with human vertebrae for interbody devices varying in size/placement. Bone surrogates are alternatives when human cadaveric vertebrae are unavailable. Synthetic vertebrae modeling cortices, endplates, and cancellous bone have been developed as an alternative to polyurethane foam blocks for testing interbody device subsidence. Indentors placed on the endplates of synthetic vertebrae, foam blocks, and human vertebrae were subjected to uniaxial compression. Subsidence, measured with custom-made extensometers, was evaluated for an indentor seated either centrally or peripherally on the endplate. Failure force and indentation stiffness were determined from force-displacement curves. Subsidence measures in human vertebrae varied with indentor placement: failure forces were higher and indentors subsided less with peripheral placement. Subsidence measures in foam blocks were insensitive to indentor size/placement; they were similar to human vertebrae for centrally placed but not for peripherally placed indentors. Although subsidence measures in synthetic vertebrae were sensitive to indentor size/placement, failure force and indentation stiffness were overestimated, and subsidence underestimated, for both centrally placed and peripherally placed indentors. The synthetic endplate correctly represented the human endplate geometry, and thus, failure force, stiffness, and subsidence in synthetic vertebrae were sensitive to indentor size/placement. However, the endplate was overly strong and thus synthetic vertebrae did not accurately model indentor subsidence in human cadaveric vertebrae. Foam blocks captured subsidence measures more accurately than synthetic vertebrae for centrally placed indentors, but because of their uniform density were not sufficiently robust to

  4. 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

    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...

  5. Evaluation of the trauma and bone metabolism after internal absorbable screw and metal screw fixation treatment of tibia-fibula fracture

    Directory of Open Access Journals (Sweden)

    Guang-Bin Yuan

    2017-03-01

    Full Text Available Objective: To study the trauma and bone metabolism after internal absorbable screw and metal screw fixation treatment of tibia-fibula fracture. Methods: 78 patients with tibia-fibula fracture who received internal fixation surgery in our hospital between May 2013 and October 2015 were selected and randomly divided into absorbable group and metal group (n=39 who accepted internal absorbable screw fixation and internal metal screw fixation respectively. 3 d after operation, serum was collected to determine the levels of inflammatory factors, pain mediators, stress hormones and bone metabolism indexes. Results: Serum inflammatory mediators procalcitonin (PCT, Resistin, C-reactive protein (CRP, interleukin-6 (IL-6, and tumor necrosis factor-α (TNF-α, pain mediators substance P (SP, prostaglandin E2 (PGE2 and NPY, stress hormones norepinephrine (NE, epinephrine (E and cortisol (Cor as well as bone resorption marker molecules C-terminal telopeptides of type I collagen (CTX-I and C-terminal telopeptides of type II collagen (CTX-II levels of absorbable group were significantly lower than those of metal group (P<0.05 while bone formation marker molecules N-MID osteocalcin (N-MID and N-terminal propeptide of procollagen type I (PINP levels were significantly higher than those of metal group (P<0.05. Conclusions: The trauma degree of internal absorbable screw fixation treatment of tibia-fibula fracture is weaker than that of internal metal screw fixation, and the bone metabolism activity is better than that of internal metal screw fixation.

  6. Outcome of nonunion fractures in dogs treated with fixation, compression resistant matrix, and recombinant human bone morphogenetic protein-2.

    Science.gov (United States)

    Massie, Anna M; Kapatkin, Amy S; Fuller, Mark C; Verstraete, Frank J M; Arzi, Boaz

    2017-03-20

    To report the use of compression resistant matrix (CRM) infused with recombinant human bone morphogenetic protein (rhBMP-2) prospectively in the healing of nonunion long-bone fractures in dogs. A longitudinal cohort of dogs that were presented with nonunion fractures were classified and treated with CRM soaked with rhBMP-2 and fracture fixation. They were followed with serial radiographs and evaluated for healing times and complications according to the time frame and definitions previously established for orthopaedic clinical cases. Eleven nonunion fractures in nine dogs were included. Median healing time was 10 weeks (range: 7-20 weeks). Major perioperative complications due to bandage morbidity were encountered in two of 11 limbs and resolved. All other complications were minor. They occurred perioperatively in eight of 11 limbs. Minor follow-up complications included short-term in one of two limbs, mid-term in one of three, and long-term in four of five limbs. Nine limbs returned to full function and two limbs returned to acceptable function at the last follow-up. Nonunion fractures given a poor prognosis via standard-of-care treatment were successfully repaired using CRM with rhBMP-2 accompanying fixation. These dogs, previously at high risk of failure, returned to full or acceptable function.

  7. 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.

  8. Patient-tailored plate for bone fixation and accurate 3D positioning in corrective osteotomy

    NARCIS (Netherlands)

    Dobbe, J. G. G.; Vroemen, J. C.; Strackee, S. D.; Streekstra, G. J.

    2013-01-01

    A bone fracture may lead to malunion of bone segments, which gives discomfort to the patient and may lead to chronic pain, reduced function and finally to early osteoarthritis. Corrective osteotomy is a treatment option to realign the bone segments. In this procedure, the surgeon tries to improve

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

    Directory of Open Access Journals (Sweden)

    Jan Wieding

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

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

    Science.gov (United States)

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

    2012-01-01

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

  11. Enhancing pedicle screw fixation in the aging spine with a novel bioactive bone cement: an in vitro biomechanical study.

    Science.gov (United States)

    Zhu, Qingan; Kingwell, Stephen; Li, Zhaoyang; Pan, Haobo; Lu, William W; Oxland, Thomas R

    2012-08-01

    A paired biomechanical study of pedicle screws augmented with bone cement in a human cadaveric and osteoporotic lumbar spine model. OBJECTIVES.: To evaluate immediate strength and stiffness of pedicle screw fixation augmented with a novel bioactive bone cement in an osteoporotic spine model and compare it with polymethylmethacrylate (PMMA) cement. A novel bioactive bone cement, containing nanoscale particles of strontium and hydroxyapatite (Sr-HA), can promote new bone formation and osteointegration and provides a promising reinforcement to the osteoporotic spine. Its immediate mechanical performance in augmenting pedicle screw fixation has not been evaluated. Two pedicle screws augmented with Sr-HA and PMMA cement were applied to each of 10 isolated cadaveric L3 vertebrae. Each screw was subjected to a toggling test and screw kinematics were calculated. The pedicle screw was subjected to a pullout test until failure. Finally, the screw coverage with cement was measured on computed tomographic images. Screw translations in the toggling test were consistently larger in the Sr-HA group than in the PMMA group (1.4 ± 1.2 mm vs. 1.0 ± 1.1 mm at 1000 cycles). The rotation center was located closer to the screw tip in the Sr-HA group (19% of screw length) than in the PMMA group (37%). The only kinematic difference between Sr-HA and PMMA cements was the screw rotation at 1000 cycles (1.5° ± 0.9° vs. 1.3° ± 0.6°; P = 0.0026). All motion parameters increased significantly with more loading cycles. The pullout force was higher in the PMMA group than the Sr-HA group (1.40 ± 0.63 kN vs. 0.93 ± 0.70 kN), and this difference was marginally significant (P = 0.051). Sr-HA cement covered more of the screw length than PMMA cement (79 ± 19% vs. 43 ± 19%) (P = 0.036). This paired-design study identified some subtle but mostly nonsignificant differences in immediate biomechanical fixation of pedicle screws augmented with the Sr-HA cement compared with the PMMA cement.

  12. 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.

    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,

  13. Intramedullary nail fixation of non-traditional fractures: Clavicle, forearm, fibula.

    Science.gov (United States)

    Dehghan, Niloofar; Schemitsch, Emil H

    2017-06-01

    Locked intramedullary fixation is a well-established technique for managing long-bone fractures. While intramedullary nail fixation of diaphyseal fractures in the femur, tibia, and humerus is well established, the same is not true for other fractures. Surgical fixations of clavicle, forearm and ankle are traditionally treated with plate and screw fixation. In some cases, fixation with an intramedullary device is possible, and may be advantageous. However, there is however a concern regarding a lack of rotational stability and fracture shortening. While new generation of locked intramedullary devices for fractures of clavicle, forearm and fibula are recently available, the outcomes are not as reliable as fixation with plates and screws. Further research in this area is warranted with high quality comparative studies, to investigate the outcomes and indication of these fractures treated with intramedullary nail devices compared to intramedullary nail fixation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. 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...... skeletal conditions (particularly of the lower extremities) impede optimal intensive care of these patients. Therefore in a polytrauma setup, primary operative stabilization of the femur is mandatory and generally accepted, whereas the optimal fixation procedure is still a source of controversies...

  15. Lag screw fixation of dorsal cortical stress fractures of the third metacarpal bone in 116 racehorses.

    Science.gov (United States)

    Jalim, S L; McIlwraith, C W; Goodman, N L; Anderson, G A

    2010-10-01

    The effectiveness and best method to manage dorsal cortical stress fractures is not clear. This study was performed to evaluate the success of lag screw fixation of such fractures in a population of Thoroughbred racehorses. Lag screw fixation of dorsal cortical stress fractures is an effective surgical procedure allowing racehorses to return to their preoperative level of performance. The records of 116 racehorses (103 Thoroughbreds) admitted to Equine Medical Centre, California between 1986 and 2008 were assessed. Information obtained from medical records included subject details, limb(s) affected, fracture configuration, length of screw used in repair and presence of concurrent surgical procedures performed. Racing performance was evaluated relative to these factors using Fisher's exact test and nonparametric methods with a level of significance of Phorses, 83% raced preoperatively and 83% raced post operatively, with 63% having ≥5 starts. There was no statistically significant association between age, gender, limb affected, fracture configuration or presence of concurrent surgery and likelihood of racing post operatively or of having 5 or more starts. The mean earnings per start and the performance index for the 3 races following surgery were lower compared to the 3 races prior to surgery; however, 29 and 45% of horses either improved or did not change their earnings per start and performance index, respectively. Data show that lag screw fixation is successful at restoring ability to race in horses suffering from dorsal cortical stress fractures. © 2010 EVJ Ltd.

  16. Assessing bone volume for orthodontic miniplate fixation below the maxillary frontal process.

    Science.gov (United States)

    Präger, T M; Brochhagen, H G; Mischkowski, R; Jost-Brinkmann, P-G; Müller-Hartwich, R

    2014-09-01

    The maxillary bone below the frontal process is used for orthodontic anchorage; indications have included skeletally anchored protraction of the maxilla for treating Class III malocclusions or the intrusion of teeth in patients with a deep bite. This study was conducted to assess the condition of bone before cortically implanting miniplates in that area of the maxilla. A total of 51 thin-sliced computed tomography scans of 51 fully-dentate adult patients (mean age 24.0 ± 8.1 years; 27 men and 24 women) obtained prior to third-molar osteotomy were evaluated. Study parameters included total bone thickness, thickness of the facial cortical plate, and width of the nasal maxillary buttress. All these parameters were measured at different vertical levels. The bone volume adjacent to the piriform aperture was most pronounced at the basal level and decreased progressively toward more cranial levels. The basal bone structure had a mean total thickness of 7.8 mm, facial cortical plate thickness of 1.9 mm, and nasal maxillary buttress width of 9.2 mm. At 16 mm cranial to the aperture base, these values fell to 5.6 mm, 1.3 mm, and 5.8 mm, respectively. These bone measurements suggest that screws 7 mm in length can be inserted at the base level of the piriform aperture and screws 5 mm long at the cranial end of the bone.

  17. Characterization of bone-implant fixation using modal analysis: application to a press-fit implant model.

    Science.gov (United States)

    Swider, P; Guérin, G; Baas, Joergen; Søballe, Kjeld; Bechtold, Joan E

    2009-08-07

    Orthopaedic implant fixation is strongly dependant upon the effective mechanical properties of newly formed tissue. In this study, we evaluated the potential of modal analysis to derive viscoelastic properties of periprosthetic tissue. We hypothesized that Young's modulus and loss factor could be obtained by a combined theoretical, computational and experimental modal analysis approach. This procedure was applied to ex vivo specimens from a cylindrical experimental implant placed in cancellous bone in an unloaded press-fit configuration, obtained after a four week observation period. Four sections each from seven textured titanium implants were investigated. The first resonant frequency and loss factor were measured. Average experimentally determined loss factor was 2% (SD 0.4%) and average first resonant frequency was 2.1 KHz (SD: 50). A 2D axisymmetric finite element (FE) model identified effective Young's modulus of tissue using experimental resonant frequencies as input. Average value was 42 MPa (SD: 2.4) and no significant difference between specimens was observed. In this pilot study, the non-destructive method allowed accurate measure of dynamic loss factor and resonant frequency and derivation of effective Young's modulus. Prior to implementing this dynamic protocol for broader mechanical evaluation of experimental implant fixation, further work is needed to determine if this affects results from subsequent destructive shear push-out tests.

  18. Central tarsal bone fractures in horses not used for racing: Computed tomographic configuration and long-term outcome of lag screw fixation.

    Science.gov (United States)

    Gunst, S; Del Chicca, F; Fürst, A E; Kuemmerle, J M

    2016-09-01

    There are no reports on the configuration of equine central tarsal bone fractures based on cross-sectional imaging and clinical and radiographic long-term outcome after internal fixation. To report clinical, radiographic and computed tomographic findings of equine central tarsal bone fractures and to evaluate the long-term outcome of internal fixation. Retrospective case series. All horses diagnosed with a central tarsal bone fracture at our institution in 2009-2013 were included. Computed tomography and internal fixation using lag screw technique was performed in all patients. Medical records and diagnostic images were reviewed retrospectively. A clinical and radiographic follow-up examination was performed at least 1 year post operatively. A central tarsal bone fracture was diagnosed in 6 horses. Five were Warmbloods used for showjumping and one was a Quarter Horse used for reining. All horses had sagittal slab fractures that began dorsally, ran in a plantar or plantaromedial direction and exited the plantar cortex at the plantar or plantaromedial indentation of the central tarsal bone. Marked sclerosis of the central tarsal bone was diagnosed in all patients. At long-term follow-up, 5/6 horses were sound and used as intended although mild osteophyte formation at the distal intertarsal joint was commonly observed. Central tarsal bone fractures in nonracehorses had a distinct configuration but radiographically subtle additional fracture lines can occur. A chronic stress related aetiology seems likely. Internal fixation of these fractures based on an accurate diagnosis of the individual fracture configuration resulted in a very good prognosis. © 2015 EVJ Ltd.

  19. Percutaneous internal fixation of proximal fifth metatarsal jones fractures (Zones II and III) with Charlotte Carolina screw and bone marrow aspirate concentrate: an outcome study in athletes.

    Science.gov (United States)

    Murawski, Christopher D; Kennedy, John G

    2011-06-01

    Internal fixation is a popular first-line treatment method for proximal fifth metatarsal Jones fractures in athletes; however, nonunions and screw breakage can occur, in part because of nonspecific fixation hardware and poor blood supply. To report the results from 26 patients who underwent percutaneous internal fixation with a specialized screw system of a proximal fifth metatarsal Jones fracture (zones II and III) and bone marrow aspirate concentrate. Case series; Level of evidence, 4. Percutaneous internal fixation for a proximal fifth metatarsal Jones fracture (zones II and III) was performed on 26 athletic patients (mean age, 27.47 years; range, 18-47). All patients were competing at some level of sport and were assessed preoperatively and postoperatively using the Foot and Ankle Outcome Score and SF-12 outcome scores. The mean follow-up time was 20.62 months (range, 12-28). Of the 26 fractures, 17 were traditional zone II Jones fractures, and the remaining 9 were zone III proximal diaphyseal fractures. The mean Foot and Ankle Outcome Score significantly increased, from 51.15 points preoperatively (range, 14-69) to 90.91 at final follow-up (range, 71-100; P fixation of proximal fifth metatarsal Jones fractures, with a Charlotte Carolina screw and bone marrow aspirate concentrate, provides more predictable results while permitting athletes a return to sport at their previous levels of competition, with few complications.

  20. A Modified Technique of Fixation for Proximal Femoral Valgus Osteotomy in Abnormal Bone: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Logheswaren S

    2017-07-01

    Full Text Available The ideal size of intramedullary device to fix corrective osteotomy of proximal femur in abnormal bone in children and small patients may not be easily available. We report the successful use of Rush rod in combination with multiple Kirschner wires to fix the corrective osteotomy of coxa vara and shepherd crook deformity in two patients with osteogenesis imperfecta and fibrous dysplasia. The union was achieved on time, neck shaft angle and rotation were maintained.

  1. A STUDY OF POSTERIOR LUMBAR INTERBODY FUSION WITH LOCALLY HARVESTED SPINOLAMINECTOMY BONE GRAFT AND PEDICLE SCREW FIXATION IN SPONDYLOLISTHESIS

    Directory of Open Access Journals (Sweden)

    Pardhasaradhi M

    2017-08-01

    Full Text Available BACKGROUND Posterior Lumbar Interbody Fusion (PLIF and Transforaminal Lumbar Interbody Fusion (TLIF create intervertebral fusion by means of a posterior approach. Successful results have been reported with allograft, various cages (for interbody support, autograft and recombinant human bone morphogenetic protein‐2. Interbody fusion techniques facilitate reduction and enhance fusion. Corticocancellous laminectomy bone chips alone can be used as a means of spinal fusion in patients with single level instrumented PLIF. This has got a good fusion rate. PLIF with cage gives better fusion on radiology than PLIF with iliac bone graft, but no statistical difference in the clinical outcome. Cage use precludes complications associated with iliac bone harvesting. The reported adjacent segment degeneration was 40.5% and reoperation was 8.1% after 10 years of follow up. MATERIALS AND METHODS 30 cases of spondylolisthesis who attended the Orthopaedic Outpatient Department of Andhra Medical College, Visakhapatnam, from 2014 to 2016 were taken up for study. All the cases were examined clinically and confirmed radiologically. The patient’s age, sex, symptoms and duration were noted and were examined clinically for the status of the spine. Straight leg raising test was done and neurological examination of the lower limbs performed. All the patients were subjected to the radiological examination of the lumbosacral spine by taking anteroposterior, lateral (flexion and extension views, oblique views to demonstrate spondylolysis and spondylolisthesis. MRI and x-rays studies were done in all the cases to facilitate evaluation of the root compression disk changes and spinal cord changes. RESULTS In our study, we followed all the 30 patients after the surgery following procedure of removal of loose lamina, spinous process and fibrocartilaginous mass, PLIF with only the laminectomy bone mass and CD screw system fixation up to 2 years. 12 patients (40% had excellent

  2. [Application of acetabular tridimensional memory alloy-fixation system in treatment of old acetabular posterior wall fracture with bone defect].

    Science.gov (United States)

    Cao, Liehu; Bao, Guangquan; Zhang, Chuncai; Liu, Xinwei; Niu, Yunfei; Xu, Shuogui; Su, Jiacan

    2011-12-01

    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. 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 reduced, 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. 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'Aubigné-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%. ATMFS combined with autologous iliac bone graft and artificial ligament reconstruction of the hip joint capsule is a good

  3. Stemmed femoral knee prostheses: effects of prosthetic design and fixation on bone loss.

    NARCIS (Netherlands)

    Lenthe, G.H. van; Willems, P.C.P.H.; Verdonschot, N.J.J.; Waal Malefijt, M.C. de; Huiskes, R.

    2002-01-01

    Although the revision rates for modern knee prostheses have decreased drastically, the total number of revisions a year is increasing because many more primary knee replacements are being done. At the time of revision, bone loss is common, which compromises prosthetic stability. To improve

  4. 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. © 2013.

  5. Modifications to a 3D-printed temporal bone model for augmented stapes fixation surgery teaching.

    Science.gov (United States)

    Nguyen, Yann; Mamelle, Elisabeth; De Seta, Daniele; Sterkers, Olivier; Bernardeschi, Daniele; Torres, Renato

    2017-07-01

    Functional outcomes and complications in otosclerosis surgery are governed by the surgeon's experience. Thus, teaching the procedure to residents to guide them through the learning process as quickly as possible is challenging. Artificial 3D-printed temporal bones are replacing cadaver specimens in many institutions to learn mastoidectomy, but these are not suitable for middle ear surgery training. The goal of this work was to adapt such an artificial temporal bone to aid the teaching of otosclerosis surgery and to evaluate this tool. We have modified a commercially available 3D-printed temporal bone by replacing the incus and stapes of the model with in-house 3D-printed ossicles. The incus could be attached to a 6-axis force sensor. The stapes footplate was fenestrated and attached to a 1-axis force sensor. Six junior surgeons (residents) and seven senior surgeons (fellows or consultants) were enrolled to perform piston prosthesis placement and crimping as performed during otosclerosis surgery. The time required to perform the tasks and the forces applied to the incus and stapes were collected and analyzed. No statistically significant differences were observed between the junior and senior groups for time taken to perform the tasks and the forces applied to the incus during crimping and placement of the prosthesis. However, significantly lower forces were applied to the stapes by the senior surgeons in comparison with the junior surgeons during prosthesis placement (junior vs senior group, 328 ± 202.9 vs 80 ± 99.6 mN, p = 0.008) and during prosthesis crimping (junior vs senior group, 565 ± 233 vs 66 ± 48.6 mN, p = 0.02). We have described a new teaching tool for otosclerosis surgery based on the modification of a 3D-printed temporal bone to implement force sensors on the incus and stapes. This tool could be used as a training tool to help the residents to self-evaluate their progress with recording of objective measurements.

  6. Graft fixation in cruciate ligament reconstruction.

    Science.gov (United States)

    Brand, J; Weiler, A; Caborn, D N; Brown, C H; Johnson, D L

    2000-01-01

    Cruciate ligament reconstruction has progressed dramatically in the last 20 years. Anatomic placement of ligament substitutes has fostered rehabilitation efforts that stress immediate and full range of motion, immediate weightbearing, neuromuscular strength and coordination, and early return to athletic competition (3 months). This has placed extreme importance on secure graft fixation at the time of ligament reconstruction. Current ligament substitutes require a bony or soft tissue component to be fixed within a bone tunnel or on the periosteum at a distance from the normal ligament attachment site. Fixation devices have progressed from metal to biodegradable and from far to near-normal native ligament attachment sites. Ideally, the biomechanical properties of the entire graft construct would approach those of the native ligament and facilitate biologic incorporation of the graft. Fixation should be done at the normal anatomic attachment site of the native ligament (aperture fixation) and, over time, allow the biologic return of the histologic transition zone from ligament to fibrocartilage, to calcified fibrocartilage, to bone. The purpose of this article is to review current fixation devices and techniques in cruciate ligament surgery.

  7. Conductive hearing loss and bone conduction devices: restored binaural hearing?

    Science.gov (United States)

    Agterberg, Martijn J H; Hol, Myrthe K S; Cremers, Cor W R J; Mylanus, Emmanuel A M; van Opstal, John; Snik, Ad F M

    2011-01-01

    An important aspect of binaural hearing is the proper detection of interaural sound level differences and interaural timing differences. Assessments of binaural hearing were made in patients with acquired unilateral conductive hearing loss (UCHL, n = 11) or congenital UCHL (n = 10) after unilateral application of a bone conduction device (BCD), and in patients with bilateral conductive or mixed hearing loss after bilateral BCD application. Benefit (bilateral versus unilateral listening) was assessed by measuring directional hearing, compensation of the acoustic head shadow, binaural summation and binaural squelch. Measurements were performed after an acclimatization time of at least 10 weeks. Unilateral BCD application was beneficial, but there was less benefit in the patients with congenital UCHL as compared to patients with acquired UCHL. In adults with bilateral hearing loss, bilateral BCD application was clearly beneficial as compared to unilateral BCD application. Binaural summation was present, but binaural squelch could not be proven. To explain the poor results in the patients with congenital UCHL, two factors seemed to be important. First, a critical period in the development of binaural hearing might affect the binaural hearing abilities. Second, crossover stimulation, referring to additional stimulation of the cochlea contralateral to the BCD side, might deteriorate binaural hearing in patients with UCHL. Copyright © 2011 S. Karger AG, Basel.

  8. The biomechanical strength of a hardware-free femoral press-fit method for ACL bone-tendon-bone graft fixation.

    Science.gov (United States)

    Arnold, M P; Burger, L D; Wirz, D; Goepfert, B; Hirschmann, M T

    2017-04-01

    The purpose was to investigate graft slippage and ultimate load to failure of a femoral press-fit fixation technique for anterior cruciate ligament (ACL) reconstruction. Nine fresh-frozen knees were used. Standardized harvesting of the B-PT-B graft was performed. The femora were cemented into steel rods, and a tunnel was drilled outside-in into the native ACL footprint and expanded using a manual mill bit. The femoral bone block was fixed press-fit. To pull the free end of the graft, it was fixed to a mechanical testing machine using a deep-freezing technique. A motion capture system was used to assess three-dimensional micro-motion. After preconditioning of the graft, 1000 cycles of tensile loading were applied. Finally, an ultimate load to failure test was performed. Graft slippage in mm ultimate load to failure as well as type of failure was noted. In six of the nine measured specimens, a typical pattern of graft slippage was observed during cyclic loading. For technical reasons, the results of three knees had to be discarded. 78.6 % of total graft slippage occurred in the first 100 cycles. Once the block had settled, graft slippage converged to zero, highlighting the importance of initial preconditioning of the graft in the clinical setting. Graft slippage after 1000 cycles varied around 3.4 ± 3.2 mm (R = 1.3-9.8 mm) between the specimens. Ultimate loading (n = 9) revealed two characteristic patterns of failure. In four knees, the tendon ruptured, while in five knees the bone block was pulled out of the femoral tunnel. The median ultimate load to failure was 852 N (R = 448-1349 N). The implant-free femoral press-fit fixation provided adequate primary stability with ultimate load to failure pull forces at least equal to published results for interference screws; hence, its clinical application is shown to be safe.

  9. The treatment of scaphoid nonunion using the Ilizarov fixator without bone graft, a study of 18 cases

    Directory of Open Access Journals (Sweden)

    Bumbaširević Marko

    2011-11-01

    Full Text Available Abstract Objectives Evaluating the safety and efficacy of the Ilizarov fine-wire compression/distraction technique in the treatment of scaphoid nonunion (SNU, without the use of bone graft. Design A retrospective review of 18 consecutive patients in one centre. Patients and Methods 18 patients; 17 males; 1 female, with a mean SNU duration of 13.9 months. Patients with carpal instability, humpback deformity, carpal collapse, avascular necrosis or marked degenerative change, were excluded. Following frame application the treatment consisted of three stages: the frame was distracted 1 mm per day until radiographs showed a 2-3 mm opening at the SNU site (mean 10 days; the SNU site was then compressed for 5 days, at a rate of 1 mm per day, with the wrist in 15 degrees of flexion and 15 degrees of radial deviation; the third stage involved immobilization with the Ilizarov fixator for 6 weeks. The technique is detailed herein. Results Radiographic (CT and clinical bony union was achieved in all 18 patients after a mean of 89 days (70-130 days. Mean modified Mayo wrist scores improved from 21 to 86 at a mean follow-up of 37 months (24-72 months, with good/excellent results in 14 patients. All patients returned to their pre-injury occupations and levels of activity at a mean of 117 days. Three patients suffered superficial K-wire infections, which resolved with oral antibiotics. Conclusions In these selected patients this technique safely achieved bony union without the need to open the SNU site and without the use of bone graft.

  10. 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.

  11. Tissue-implant interface at an absorbable fracture fixation plug made of polylactide in cancellous bone of distal rabbit femur.

    Science.gov (United States)

    Pihlajamäki, H; Böstman, O; Manninen, M; Päivärinta, U; Rokkanen, P

    1994-01-01

    The tissue-implant interface at a self-reinforced poly-L-lactide (SR-PLLA) expansion plug implanted in distal rabbit femoral cancellous bone was studied histologically, histomorphometrically, and microradiographically in 35 rabbits during consolidation of a transverse transcondylar osteotomy fixed with the SR-PLLA expansion plug. The absorbable plug for internal fixation of fractures and osteotomies measured 4.5 mm in diameter and 30 mm in length and had an expandable distal locking blade system. The femoral specimens were harvested in groups of 5-10 rabbits after a follow-up time of 3, 6, 12, and 24 weeks. The intact contralateral femur served as a control. Vigorous osteogenic response to the implant was already observed at 3 weeks postoperatively, and the osteoid surface fraction at 24 weeks was still significantly higher than in the unoperated contralateral femur. Incomplete union of the osteotomy seemed to result in increased fibrous tissue formation at the tissue-implant boundary. No signs of degradation of the SR-PLLA was observed within the entire follow-up period. The number of inflammatory cells at the tissue-implant interface was low. Consequently, the short-term biocompatibility of the implant was deemed acceptable. Clinical application of the expansion plug is being planned.

  12. Early Conversion of External Fixation to Interlocked Nailing in Open Fractures of Both Bone Leg Assisted with Vacuum Closure (VAC) - Final Outcome.

    Science.gov (United States)

    Gill, Simrat Pal Singh; Raj, Manish; Kumar, Sunil; Singh, Pulkesh; Kumar, Dinesh; Singh, Jasveer; Deep, Akash

    2016-02-01

    Management of compound grade III fractures of both bone leg includes external stabilization for long period, followed by various soft tissue coverage procedures. Primary interlocking of tibia had been also done with variable results. External fixation for long time without any bone loss often leads to infected nonunion, loss of reduction, pin tract infection and failure of fixation, primary interlocking in compound grade III fractures had shown high medullary infection rate. We managed all cases of compound grade III A/B fractures with primary external fixation, simultaneous wound management using vacuum assisted closure (VAC) followed by early conversion to interlocking within 2 weeks of fixator application. To determine the effectiveness of vacuum assisted closure (VAC) for the early conversion of external fixator to definitive interlocking in open fractures of the both bone leg. In current study we selected 84 cases of compound grade IIIA/B diaphyseal fractures of both bone leg during period of May 2010 to September 2013. We managed these cases by immediate debridement and application of external fixation followed by repeated debridement, application of vacuum assisted closure (VAC) and conversion to interlocking within two weeks. Out of 84 cases union was achieved in 80(95%) of cases with definitive tibial interlocking. Excellent to good result were obtained in 77(91.8%) of cases and fair to poor result seen in rest of 7(8.2%) of cases according to modified Ketenjian's criteria. 5 out of these 7 poor result group cases were from Compound Grade III B group to start with. Deep infection rate in our series were 7% i.e. total 6 cases and 4 out of these were from compound Grade III B group to start with. Vacuum assisted closure (VAC) give a good help for rapid closure of the wound and help in early conversion to definitive intramedullary nailing. Reamed nail could well be used in compound grade IIIA/B fractures without increasing the risk of infection. It gives

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

    NARCIS (Netherlands)

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

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

  14. The impact of zoledronic acid on regenerate and native bone after consolidation and removal of the external fixator: an animal model study.

    Science.gov (United States)

    Saghieh, Said; Khoury, Nabil J; Tawil, Ayman; Masrouha, Karim Z; Musallam, Khaled M; Khalaf, Kinda; Dosh, Laura; Jaouhari, Rosemarie Reich; Birjawi, Ghina; El-Hajj-Fuleihan, Ghada

    2010-02-01

    We investigated the role of zoledronic acid on the regenerate and native bone after consolidation and removal of the external fixator in a rabbit model of distraction osteogenesis using 28 New Zealand white rabbits. The rabbits were randomly distributed into two groups. The first group received three doses of zoledronic acid (ZA) 0.1 mg/kg subcutaneously at weekly intervals while the second group received injections of sterile saline. Distraction started on day 7 at a rate of 0.8 mm/day for 12 days. At week 3 the average lengthening, regenerate density, and regenerate continuity were comparable between the two groups. At week 11 the regenerate in the treated group had a significant increase in Bone Mineral Density (BMD) and Bone Mineral Content (BMC) compared to the placebo group. On axial compression, the regenerate showed an increase in the peak load and a higher modulus of elasticity in the treated group. At 6 months, radiographs demonstrated signs of osteopenia of the proximal metaphysis in the control group, and failure of new bone formation around the pin sites in the treated group. BMC and BMD value differences between the two groups were not statistically significant. Histologically, there was persistence of more bone trabeculae in the medullary canal of the regenerate with the persistence of the pin-holes in the treated group. Mechanically, the regenerates in the treated group remain stronger in resisting the axial compression. The proximal fragment in the treated group exhibited a statistically significant decrease in the peak load, toughness and efail %. In conclusion, bisphosphonate-treated rabbits have a stronger regenerate during distraction, and directly after removal of the fixator. They do not develop disuse osteopenia in their lengthened tibia. This treatment may shorten the time in the external fixator and prevent fragility fractures in the treated extremity. However, its long-term safety has not yet been established. (c) 2009 Elsevier Inc. All

  15. Arthroscopically Assisted Coracoclavicular Fixation Using a Single Flip Button Device Technique: What Are the Main Factors Affecting the Maintenance of Reduction?

    Directory of Open Access Journals (Sweden)

    Yong-Beom Lee

    2017-01-01

    Full Text Available Background. Among coracoclavicular (CC fixation techniques, the use of flip button device was demonstrated to have successful outcomes with the advantage of being able to accommodate an arthroscopic procedure. Purpose. This study was conducted to investigate the factors associated with loss of fixation after arthroscopically assisted CC fixation using a single flip button device for acromioclavicular (AC joint dislocations. Materials and Methods. We enrolled a total of 47 patients (35 men and 12 women. Plain radiography was performed at a mean of 24 months postoperatively to evaluate the final radiological outcome. The primary outcome measure was a long-term reduction of the AC joint for at least 24 months. Results. We found that 29 patients had a high quality reduction (61.7% and 18 patients had a low quality reduction (38.3% in initial postoperative CT findings. Our study showed that the duration (5 days from injury to treatment and the quality of initial postoperative reduction were significantly associated with the maintenance of reduction at final follow-up. Conclusion. Our study showed that maintaining stable reduction after arthroscopically assisted CC fixation using a single flip button device technique is difficult especially in patients who received delayed treatment or whose initial reduction quality was poor.

  16. Effect of mid-frequency pulse therapy combined with external fixation on bone metabolism, inflammatory response and oxidative stress in patients with osteoporotic distal radial fractures

    Directory of Open Access Journals (Sweden)

    Bao-Ning Luo

    2017-09-01

    Full Text Available Objective: To study the effect of mid-frequency pulse therapy combined with external fixation on bone metabolism, inflammatory response and oxidative stress in patients with osteoporotic distal radial fractures. Methods: A total of 72 patients with osteoporotic distal radial fractures who were treated in the hospital between September 2015 and January 2017 were collected and divided into control group (n=36 and observation group (n=36 according to the random number table method. Control group received routine external fixation, and observation group received mid-frequency pulse therapy combined with external fixation. The differences in serum levels of bone metabolism indexes, inflammatory factors and oxidative stress indexes were compared between two groups of patients before and after treatment. Results: Before treatment, differences in serum levels of bone metabolism indexes, inflammatory factors and oxidative stress indexes were not statistically significant between the two groups. After 1 month of treatment, serum BGP, TAC and SOD levels of both groups of patients were higher than those before treatment while β-CTX, AKP, TRAP, CRP, IL-1β, IL-6 and MDA levels were lower than those before treatment, and serum BGP, TAC and SOD levels of observation group were higher than those of control group while β-CTX, AKP, TRAP, CRP, IL-1β, IL-6 and MDA levels were lower than those of control group. Conclusion: Mid-frequency pulse therapy combined with external fixation can promote fracture healing and reduce postoperative inflammatory response and oxidative stress response in patients with osteoporotic distal radial fracture.

  17. Surgical treatment of bilateral nondisplaced isthmic lysis by interlaminar fixation device

    Directory of Open Access Journals (Sweden)

    Keyvan Mostofi

    2017-01-01

    Full Text Available Study Design: Spondylolysis is a defect in the portion of pars interarticularis. The latter affects approximately 6% of the population. It is caused by repetitive trauma in hyperextension. Low back pain is the most common symptom. Methods: We implanted interspinous process devices in 12 patients with isthmic lysis without spondylolisthesis for low back pain. The purpose of the surgery was to conduct a minimally invasive procedure. Results: In eight cases, patients became asymptomatic. In two cases, there has been a considerable improvement. In two cases, no change had been noted. Conclusion: This good result motivates us to consider this approach a part of therapeutic arsenal for some cases of spondylolysis.

  18. Preoperative headband assessment for semi-implantable bone conduction hearing devices in conductive hearing loss: is it useful or misleading?

    Science.gov (United States)

    Rainsbury, James W; Williams, Blair A; Gulliver, Mark; Morris, David P

    2015-02-01

    To establish whether preoperative assessment using a conventional, percutaneous bone conducting implant (pBCI) processor on a headband accurately represents postoperative performance of a semi-implantable BCI (siBCI). Retrospective case series. Tertiary otology unit. Five patients with chronic otitis media (implanted unilaterally) and one with bilateral congenital ossicular fixation (implanted bilaterally). Semi-implantable bone conduction hearing implant. Functional hearing gain; preoperative (headband) versus postoperative (aided) speech discrimination; unaided bone conduction (BC) versus postoperative (aided) soundfield threshold. Significant functional gain was seen at all frequencies (one-tailed t test p G 0.01; n = 7). There was a 50 dB improvement in median speech reception threshold (SRT) from 70 dB unaided to 20 dB aided. Compared to the preoperative BC, aided siBCI thresholds were worse at 0.5 kHz, but at frequencies from 1 to 6 kHz, the siBCI closely matched the bone curve ( p G 0.01). The siBCI performed better than both pBCI processors on a headband at 3 to 4 kHz, except 1 kHz ( p G 0.01). BC thresholds may be a better indicator of implant performance than headband assessment. Candidacy assessment for siBCI implantation that relies on headband testing with pBCI processors should be interpreted with caution because the headband may under-represent the implanted device. This seems to be especially true at 3 kHz and above and may make it difficult for surgeons to conduct accurate informed consent discussions with patients about the realistic anticipated outcomes and benefits of the procedure.

  19. Densitometric comparison of 3 occipital regions for suitability of fixation.

    Science.gov (United States)

    Das, Chandan; Newcomb, Anna G U S; Gaudin, Daniel P; Crawford, Neil R

    2016-04-01

    Atlantooccipital fixation is an important technique in the treatment of upper cervical spine instability. Important considerations for implant devices are obtrusiveness and propagation of torque through the device caused by cervical rotation. The authors evaluated the feasibility of 3 regions of the occiput as sites for occipitocervical fixation by examining bone mineral density at these locations. Unembalmed occiputs of 9 male and 4 female cadavers were used (mean age at time of death was 61.6 years, range 36-68 years). Studies were undertaken using caliper measurements and dual-energy x-ray absorptiometry of the superior nuchal line (SNL), the external occipital protuberance (EOP), and the inferior nuchal line (INL). Data indicate that the bone at the INL has a similar volumetric bone density as the bone at the SNL, despite having half the thickness. Also, the volumetric bone density increases laterally along the nuchal lines. Most hardware fixation is centered on stabilization at the EOP and the SNL. On the basis of these radiological results, the INL shows promise as a potential alternative site for screw placement in occipitocervical fixation.

  20. A biomechanical comparison of headless tapered variable pitch and AO cortical bone screws for fixation of a simulated slab fracture in equine third carpal bones.

    Science.gov (United States)

    Bueno, Aloisio C D; Galuppo, Larry D; Taylor, Kenneth T; Jensen, David G; Stover, Susan M

    2003-01-01

    To compare the mechanical shear strengths and stiffnesses obtained from in vitro testing of a simulated complete third carpal bone (C3) frontal plane radial facet slab fracture (osteotomy) stabilized with either a 4/5 Acutrak (AT) compression screw or a 4.5-mm AO cortical bone (AO) screw inserted in lag fashion. Drilling, tapping, and screw insertion torques, forces, and times also were compared between AT and AO implants. In vitro biomechanical assessment of site preparation, screw insertion, and shear failure test variables of bone screw stabilized simulated C3 slab fracture in paired cadaveric equine carpi. Eight pairs of cadaveric equine C3 without orthopedic abnormalities. Standardized simulated C3 slab fractures were repaired with either AO or AT screws (AO/C3 and AT/C3 groups, respectively). Drilling, tapping, and screw insertion torques, forces, and times were measured with a materials testing machine for each screw type. Repaired specimens were tested in axially oriented shear until failure. Paired Students t-tests were used to assess differences between site preparation, screw insertion, and shear testing variables. Significance was set at P bone fragment measurements of the standardized simulated C3 slab fractures created for AO or AT screws. There were no significant differences for mean and maximum drilling torques; however, the tapered AT drill had greater maximum drilling force compared with the 3.2-mm and 4.5-mm AO drill bits. Mean insertion torque and force measured from the self-tapping AT screw were not significantly different compared with the 4.5-mm AO tap. There were no significant differences in maximum screw torque among constructs. Total procedure time was significantly longer for the AT group (5.8 +/- 1.6 minutes) compared with the AO group (2.9 +/- 1.1 minutes; P =.001). AT stabilized specimens had significantly greater mean +/- SD initial shear stiffness (3.64 +/- 1.08 kN/mm) than AO specimens (1.64 +/- 0.73 kN/mm; P =.005). All other

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

    Directory of Open Access Journals (Sweden)

    Mauffrey Cyril

    2012-03-01

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

  2. 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

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

    Science.gov (United States)

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

    2014-08-22

    The purpose of the present study was to compare the results of various types of anchor applications with or without augmentation in both osteopenic and severely osteoporotic bone models. Two different types of suture anchors were tested in severely osteoporotic (SOP) and osteopenic polyurethane (PU) foam blocks using an established protocol. An Instron machine applied static loading parallel to the axis of insertion until failure, and the mean anchor failure strengths were calculated. The mode of failure (anchor pullout, suture tear) was recorded. The anchors tested included the Corkscrew (CS) (Arthrex Inc., Naples, FL, USA) (without augmentation, polymethylmethacrylate (PMMA)-augmented, and bioabsorbable tricalcium phosphate (TCP) cement-augmented) and Corkscrew FT II (CS FT II) 5.5 mm (without augmentation as used routinely). The mean failure loads for both SOP and osteopenic PU foam blocks, respectively, were as follows: CS, 16.2 and 212.4 N; CS with TCP, 75.2 and 396 N; CS with PMMA, 101.2 and 528.8 N; CS FT II, 13.8 and 339.8 N. Augmentation of CS with TCP or PMMA would be essential to SOP bones. In the osteopenic bone model, although anchor fixation augmented with PMMA is the best fixation method, CS augmented with TCP cement or CS FT II without any need for augmentation may also be used as an alternative.

  4. Microstructural, mechanical and corrosion characteristics of heat-treated Mg-1.2Zn-0.5Ca (wt%) alloy for use as resorbable bone fixation material.

    Science.gov (United States)

    Ibrahim, Hamdy; Klarner, Andrew D; Poorganji, Behrang; Dean, David; Luo, Alan A; Elahinia, Mohammad

    2017-05-01

    Mg-Zn-Ca alloys have grabbed most of the recent attention in research attempting to develop an Mg alloy for bone fixation devices due to their superior biocompatibility. However, early resorption and insufficient strength remain the main problems that hinder their use. Heat treatment has previously been thoroughly studied as a post-shaping process, especially after the fabrication of complex parts (e.g. porous structures) by 3D-printing or powder metallurgy. In this work, the effect of heat treatment on Mg-1.2Zn-0.5Ca (wt%) alloy's microstructural, mechanical and corrosion properties was studied. The surface morphology of samples was characterized by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and x-ray diffraction (XRD). Hardness, compression and tensile tests were conducted, while the in vitro corrosion characteristics of the prepared samples were determined using potentiodynamic polarization (PDP) and immersion tests. It was found that increasing the age hardening duration up to 2-5h increased the heat-treated Mg-1.2Zn-0.5Ca alloy's mechanical properties. Further increase in the age hardening duration did not result in further enhancement in mechanical properties. Similarly, heat treatment significantly altered the Mg-1.2Zn-0.5Ca alloy's in vitro corrosion properties. The corrosion rate of the Mg-1.2Zn-0.5Ca alloy after the heat treatment process was reduced to half of that for the as-cast alloy. XRD results showed the formation of biocompatible agglomerations of hydroxyapatite (HA) and magnesium hydroxide (Mg(OH) 2 ) on the corroded surface of the heat-treated Mg-1.2Zn-0.5Ca alloy samples. The performed heat treatment process had a significant effect on both mechanical and corrosion properties of the prepared Mg-1.2Zn-0.5Ca alloy. The age hardening duration which caused the greatest increase in mechanical and the most slowed corrosion rate for Mg-1.2Zn-0.5Ca alloy material was between 2 and 5h. Copyright © 2017

  5. Preclinical evaluation of the effect of the combined use of the Ethicon Securestrap® Open Absorbable Strap Fixation Device and Ethicon Physiomesh™ Open Flexible Composite Mesh Device on surgeon stress during ventral hernia repair

    Directory of Open Access Journals (Sweden)

    Sutton N

    2017-12-01

    Full Text Available Nadia Sutton,1 Melinda H MacDonald,2 John Lombard,1 Bodgan Ilie,3 Piet Hinoul,4 Douglas A Granger5,6 1Global Health Economics and Market Access, Johnson & Johnson Medical Devices, New Brunswick, NJ, USA; 2Preclinical Center of Excellence, Johnson & Johnson Medical Devices Companies, Somerville, NJ, USA; 3Biostatistics, Ethicon, Somerville, NJ, USA; 4Medical Affairs, Ethicon, Somerville, NJ, USA; 5Institute for Interdisciplinary Salivary Bioscience Research (IISBR, University of California at Irvine, Irvine, CA, USA; 6Johns Hopkins University School of Nursing, Bloomberg School of Public Health, and School of Medicine, Baltimore, MD, USA Aim: To evaluate whether performing ventral hernia repairs using the Ethicon Physiomesh™ Open Flexible Composite Mesh Device in conjunction with the Ethicon Securestrap® Open Absorbable Strap Fixation Device reduces surgical time and surgeon stress levels, compared with traditional surgical repair methods. Methods: To repair a simulated ventral incisional hernia, two surgeries were performed by eight experienced surgeons using a live porcine model. One procedure involved traditional suture methods and a flat mesh, and the other procedure involved a mechanical fixation device and a skirted flexible composite mesh. A Surgery Task Load Index questionnaire was administered before and after the procedure to establish the surgeons’ perceived stress levels, and saliva samples were collected before, during, and after the surgical procedures to assess the biologically expressed stress (cortisol and salivary alpha amylase levels. Results: For mechanical fixation using the Ethicon Physiomesh Open Flexible Composite Mesh Device in conjunction with the Ethicon Securestrap Open Absorbable Strap Fixation Device, surgeons reported a 46.2% reduction in perceived workload stress. There was also a lower physiological reactivity to the intraoperative experience and the total surgical procedure time was reduced by 60

  6. Rotary powered device for bone marrow aspiration and biopsy yields excellent specimens quickly and efficiently.

    Science.gov (United States)

    Swords, Ronan T; Kelly, Kevin R; Cohen, Stephen C; Miller, Larry J; Philbeck, Thomas E; Hacker, Sander O; Spadaccini, Cathy J; Giles, Francis J; Brenner, Andrew J

    2010-06-01

    Recently, a new FDA-cleared battery powered bone marrow biopsy system was developed to allow operators access to the bone marrow space quickly and efficiently. A pre-clinical evaluation of the device (OnControl, Vidacare Corporation, San Antonio, TX, USA) on anesthetized pigs was conducted, in addition to a clinical evaluation in hematology clinic patients requiring a bone marrow biopsy. Twenty-six samples were collected from the swine model. No cellular artifact or thermal damage was reported in any of the samples obtained. For the clinical evaluation of the device, 16 patients were recruited. Mean time from needle contact with skin to needle removal was 38.5 +/- 13.94 seconds. No complications were reported. In this study, the manual and powered samples were equivalent in specimen quality. In the patients evaluated, the device was safe, easy to use and the mean procedural time was significantly faster than previously reported with a manual technique.

  7. CT-guided percutaneous screw fixation plus cementoplasty in the treatment of painful bone metastases with fractures or a high risk of pathological fracture

    Energy Technology Data Exchange (ETDEWEB)

    Pusceddu, Claudio; Ballicu, Nicola; Fele, Rosa Maria; Sotgia, Barbara; Melis, Luca [Oncological Hospital ' ' A. Businco' ' , Regional Referral Center for Oncologic Diseases, Division of Interventional Radiology, Department of Oncological Radiology, Cagliari (Italy); Fancellu, Alessandro [University of Sassari, Department of Clinical and Experimental Medicine, Sassari (Italy)

    2017-04-15

    To evaluate the feasibility and effectiveness of computed tomography (CT)-guided percutaneous screw fixation plus cementoplasty (PSFPC), for either treatment of painful metastatic fractures or prevention of pathological fractures, in patients who are not candidates for surgical stabilization. Twenty-seven patients with 34 metastatic bone lesions underwent CT-guided PSFPC. Bone metastases were located in the vertebral column, femur, and pelvis. The primary end point was the evaluation of feasibility and complications of the procedure, in addition to the length of hospital stay. Pain severity was estimated before treatment and 1 and 6 months after the procedure using the visual analog scale (VAS). Functional outcome was assessed by improved patient walking ability. All sessions were completed and well tolerated. There were no complications related to either incorrect positioning of the screws during bone fixation or leakage of cement. All patients were able to walk within 6 h after the procedure and the average length of hospital stay was 2 days. The mean VAS score decreased from 7.1 (range, 4-9) before treatment to 1.6 (range, 0-6), 1 month after treatment, and to 1.4 (range 0-6) 6 months after treatment. Neither loosening of the screws nor additional bone fractures occurred during a median follow-up of 6 months. Our results suggest that PSFPC might be a safe and effective procedure that allows the stabilization of the fracture and the prevention of pathological fractures with significant pain relief and good recovery of walking ability, although further studies are required to confirm this preliminary experience. (orig.)

  8. Dynamic compression plate (DCP) fixation of propagating medial condylar fractures of the third metacarpal/metatarsal bone in 30 racehorses: retrospective analysis (1990-2005).

    Science.gov (United States)

    Goodrich, L R; Nixon, A J; Conway, J D; Morley, P S; Bladon, B M; Hogan, P M

    2014-11-01

    An in-depth review of dynamic compression plate (DCP) fixation of propagating medial condyle fractures of the third metacarpus or metatarsus has not been previously reported. To describe the technique, evaluate short-term outcome and long-term race performance of racehorses that underwent DCP fixation for repair of propagating or spiralling medial condylar fractures of the third metacarpal (McIII) or metatarsal (MtIII) bone. Retrospective case series. The surgical case records of 30 horses with propagating fractures of the medial condyle of McIII or MtIII were reviewed. Medical information included: age, breed, sex, presentation, how injury occurred (racing or training), surgical treatment and post operative complications. Racing information included: starts, top 3 placing and career earnings. Long propagating fractures of the medial condyle of Mc/tIII were identified in 23 Thoroughbred (TB) and 7 Standardbred (STB) racehorses. The fracture spiralled proximally in 22 of 30 cases (73%). Standardbreds had a higher propensity for hindlimb involvement (71%), whereas TBs tended to have more front limb involvement (61%). Twelve of 30 (40%) horses raced post surgery. Career earnings were significantly lower for TB horses with medial condylar fractures; $34,916 when compared with the national average of $60,841 (P≤0.03). Overall, horses having DCP fixation for medial condylar fractures had less starts post surgery (3.1 TBs and 5.8 STBs) compared with the national average (7 TBs and 17.3 STBs) and decreased lifetime starts 13.4 (TBs) compared with 17.3 nationally. Propagating medial condyle fractures can be repaired with plate fixation to potentially lessen the risk of catastrophic fracture destabilisation and return to racing can be expected in 40% of horses. Further prospective studies are warranted comparing lag screw fixation with DCP fixation for repair of severe medial condylar fractures of the metacarpus/metatarsus. © 2013 The Authors. Equine Veterinary Journal

  9. 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.)

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

    Directory of Open Access Journals (Sweden)

    Jia-ming LIU

    2015-11-01

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

  11. Biomechanics of intramedullary fracture fixation.

    Science.gov (United States)

    Kyle, R F

    1985-11-01

    Intramedullary rodding allows excellent control of bending forces on long bone fractures when adequate sized rods are used. This is made possible by reaming when necessary. Torsional stability is poor if adequate bone nail contact is not obtained and there is little bone fragment interdigitation. This can be optimized with the interlocking system, especially with proximal and distal fractures. Intramedullary rods allow transmission of compressive load so there must be adequate bone to bone contact without comminution to prevent shortening. If a great deal of comminution is present, an interlocking system must be used to resist compressive loads. The interlocked devices have not been proven to be a detriment to union and indeed are a semi-rigid fixation system when used in comminuted shaft fractures. The strength of an osteosynthesis with an intramedullary rod depends on the geometry of the rod and the geometry of the fracture complex. Both locked and nonlocked intramedullary rods perform extremely well when one understands the mechanical principles involved in intramedullary rodding and pays close attention to detail.

  12. Better performance with bone-anchored hearing aid than acoustic devices in patients with severe air-bone gap.

    Science.gov (United States)

    de Wolf, Maarten J F; Hendrix, Sander; Cremers, Cor W R J; Snik, Ad F M

    2011-03-01

    A study performed in the 1990s with analogue linear hearing aids showed that in patients with mixed hearing loss and an air-bone gap that exceeded 25 to 30 dB, speech perception was better with a bone-anchored hearing aid (Baha) than with a conventional behind-the-ear (BTE) device. The objective of the present study was to investigate whether this conclusion applies to today's digital BTEs with feedback cancellation and whether the crossover point still occurs at an air-bone gap of 25 to 30 dB. Case control. Experienced unilateral Baha users with the latest digital Baha processors were fitted with a powerful BTE with feedback cancellation. After an acclimatization period of 4 weeks, aided thresholds and speech recognition scores were determined and compared to those recorded previously with the Baha. To obtain patients' opinions, a disability-specific questionnaire was used. Participants comprised 16 subjects with bilateral mixed hearing loss participated Audiometric and speech recognition data showed similar trends to those described previously, but the crossover point had shifted to an air-bone gap of 30 to 35 dB. In the questionnaire, the BTE was rated higher than the Baha, except by the patients with an air-bone gap that exceeded an average of 45 dB. In patients with mixed hearing loss whose air-bone gap exceeded 35 dB, speech recognition is likely to be better with a Baha than with a BTE. Therefore, the Baha should receive greater consideration when mixed hearing loss is combined with a significant air-bone gap, even when there are no contraindications for BTEs. Copyright © 2010 The American Laryngological, Rhinological, and Otological Society, Inc.

  13. 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.

  14. Abutment-free bone-anchored hearing devices in children: initial results and experience.

    Science.gov (United States)

    Centric, Aaron; Chennupati, Sri Kiran

    2014-05-01

    Bone-anchored implantable hearing devices are widely accepted as a surgical option for certain types of hearing loss in both adults and children. Most commercially available devices involve a percutaneous abutment to which a sound processor attaches. The rate of complications with such bone conduction systems is greater than 20%. Most complications arise from the abutment. Recently, the Sophono (Boulder, CO) Alpha 1, an abutment-free system, has been introduced. We conducted a retrospective chart review of the first five patients who underwent implantation with the Sophono abutment-free bone conduction hearing system with the Alpha 1 processor at our institution and report here on these patients' pre- and postoperative audiometric data and clinical courses. Average improvement in pure-tone average was 32dB hearing loss and average improvement in speech response threshold was 28dB hearing loss. All patients were responding in the normal to mild hearing loss range in the operated ear after device activation. Average improvement across individual frequencies was between 17 and 37dB (SD 5.5-11dB). Our audiometric results to date are promising and have been consistent with published data on other bone-anchored hearing devices. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Bone grafting via reamer-irrigator-aspirator for nonunion of open Gustilo-Anderson type III tibial fractures treated with multiplanar external fixator

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    Kusnezov Nicholas

    2017-01-01

    Full Text Available Introduction: The purpose of this investigation was to evaluate the outcomes following reamer-irrigator-aspirator (RIA autogenous bone grafting (ABG of high-grade open tibia fracture nonunions stabilized via multiplanar external fixation. Methods: We retrospectively reviewed all patients with Gustilo-Anderson type III open tibia fractures treated with multiplanar external fixation and who underwent RIA ABG for nonunion at our institutional Level 1 Trauma Center between 2008 and 2015. All patients between 15 and 65 years of age with a minimum of six-month follow-up were included. The primary outcomes of interest were achievement of union, time to union, and incidence of revision surgery. Complications and all-cause reoperation were recorded as secondary endpoints. Results: Fifteen patients met the inclusion criteria with a mean age of 41.1 ± 14.0 years. RIA ABG was harvested from the femur in all cases, with a mean volume of 34 ± 15 mL. At an average follow-up of 13.3 ± 6.8 months, all patients achieved union, including two who required repeat RIA ABG. One patient experienced a femoral shaft fracture four months following RIA that required intramedullary fixation. The average time to union was 6.0 ± 6.3 months. Twelve patients (80% went on to union within six months and 13 (86.7% within one year. Five patients experienced a total of six post-operative complications including three deep infections, one refracture through the nonunion site, and one gradual varus deformity. Two patients in this series required a subsequent RIA autografting procedure secondary to persistent nonunion despite initial RIA. Conclusion: We found that RIA ABG offered a reliable solution to nonunion of Gustilo-Anderson type III open tibial fractures treated with multiplanar external fixation, circumventing the need to change the method of fixation.

  16. 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

  17. 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.

  18. 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.

  19. Ultrasonic Cutting Device for Bone Surgery Based on a Cymbal Transducer

    Science.gov (United States)

    Bejarano, F.; Lucas, M.; Wallace, R.; Spadaccino, A. M.; Simpson, H.

    In this study, we introduce a new prototype ultrasonic cutting device for bone surgery based on a class V flextensional cymbal transducer, configured for use in power ultrasonics applications, which removes many of the geometrical restrictions on the cutting tip of Langevin-based transducers. The benefit of incorporating a cymbal transducer is that since the cutting blade itself does not have to be tuned, blade design can focus more closely on delivering the best interaction with bone to provide a highly accurate cut. Small variations to the geometry of the blade do not affect the final resonance frequency. Also the ultrasonic device can be miniaturised to allow the design of devices for delicate orthopaedic procedures involving minimal-access surgery. The results show how the cymbal transducer, driven by a single piezoceramic disc, can excite sufficiently high vibration displacement amplitudes at lower driving voltages. This is achieved by adapting the configuration of the cymbal to remove the problem of epoxy layer debonding, and by optimising the cymbal end-cap and geometry through finite element modelling supported with experimental vibration characterisation. Preliminary characterisations of the resulting prototype ultrasonic bone cutting device, which operates at around 25 kHz, illustrate the success of this novel device design.

  20. 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.

  1. Pedicle screws with a thin hydroxyapatite coating for improving fixation at the bone-implant interface in the osteoporotic spine: experimental study in a porcine model.

    Science.gov (United States)

    Ohe, Makoto; Moridaira, Hiroshi; Inami, Satoshi; Takeuchi, Daisaku; Nohara, Yutaka; Taneichi, Hiroshi

    2018-03-30

    OBJECTIVE Instrumentation failure caused by the loosening of pedicle screws (PSs) in patients with osteoporosis is a serious problem after spinal surgery. The addition of a thin hydroxyapatite (HA) surface coating applied by using a sputtering process was reported recently to be a promising method for providing bone conduction around an implant without a significant risk of coating-layer breakage. In this study, the authors evaluated the biomechanical and histological features of the bone-implant interface (BII) of PSs with a thin HA coating in an in vivo porcine osteoporotic spine model. METHODS Three types of PSs (untreated/standard [STPS], sandblasted [BLPS], and HA-coated [HAPS] PSs) were implanted into the thoracic and lumbar spine (T9-L6) of 8 mature Clawn miniature pigs (6 ovariectomized [osteoporosis group] and 2 sham-operated [control group] pigs). The spines were harvested from the osteoporosis group at 0, 2, 4, 8, 12, or 24 weeks after PS placement and from the control group at 0 or 24 weeks. Their bone mineral density (BMD) was measured by peripheral quantitative CT. Histological evaluation of the BIIs was conducted by performing bone volume/tissue volume and bone surface/implant surface measurements. The strength of the BII was evaluated with extraction torque testing. RESULTS The BMD decreased significantly in the osteoporosis group (p surface/implant surface ratio was significantly higher for HAPSs than for STPSs after 2 weeks (p surface was maintained until 24 weeks with no detachment of the coating layer. In contrast, the bone volume/tissue volume ratio was significantly higher for HAPSs than for BLPSs or STPSs only at 4 weeks. CONCLUSIONS Using PSs with a thin HA coating applied using a sputtering process strengthens bonding at the BII, which might improve early implant fixation after spinal surgery for osteoporosis. However, the absence of increased bone mass around the screw remains a concern; prescribing osteoporosis treatment to improve bone

  2. An in vitro biomechanical comparison of hydroxyapatite coated and uncoated ao cortical bone screws for a limited contact: dynamic compression plate fixation of osteotomized equine 3rd metacarpal bones.

    Science.gov (United States)

    Durham, Myra E; Sod, Gary A; Riggs, Laura M; Mitchell, Colin F

    2015-02-01

    To compare the monotonic biomechanical properties of a broad 4.5 mm limited contact-dynamic compression plate (LC-DCP) fixation secured with hydroxyapatite (HA) coated cortical bone screws (HA-LC-DCP) versus uncoated cortical bone screws (AO-LC-DCP) to repair osteotomized equine 3rd metacarpal (MC3) bones. Experimental. Adult equine cadaveric MC3 bones (n = 12 pair). Twelve pairs of equine MC3 were divided into 3 test groups (4 pairs each) for: (1) 4 point bending single cycle to failure testing; (2) 4 point bending cyclic fatigue testing; and (3) torsional single cycle to failure testing. For the HA-LC-DCP-MC3 construct, an 8-hole broad LC-DCP (Synthes Ltd, Paoli, PA) was secured on the dorsal surface of each randomly selected MC3 bone with a combination of four 5.5 mm and four 4.5 mm HA-coated cortical screws. For the AO-LC-DCP-MC3 construct, an 8-hole 4.5 mm broad LC-DCP was secured on the dorsal surface of the contralateral MC3 bone with a combination of four 5.5 mm and four 4.5 mm uncoated cortical screws. All MC3 bones had mid-diaphyseal osteotomies. Mean test variable values for each method were compared using a paired t-test within each group. Significance was set at P < .05. Mean yield load, yield bending moment, composite rigidity, failure load, and failure bending moment, under 4 point bending, single cycle to failure, of the HA-LC-DCP fixation were significantly greater than those of the AO-LC-DCP fixation. Mean ± SD values for the HA-LC-DCP and the AO-LC-DCP fixation techniques, respectively, in single cycle to failure under 4 point bending were: yield load, 26.7 ± 2.15 and 16.3 ± 1.38 kN; yield bending moment, 527.4 ± 42.4 and 322.9 ± 27.2 N-m; composite rigidity, 5306 ± 399 and 3003 ± 300 N-m/rad; failure load, 40.6 ± 3.94 and 26.5 ± 2.52 kN; and failure bending moment, 801.9 ± 77.9 and 522.9 ± 52.2 N-m. Mean cycles to failure in 4 point bending of the HA

  3. Biomechanical considerations in intramedullary fixation of lower-extremity fracture.

    Science.gov (United States)

    Inhofe, P D

    1992-08-01

    Since Gerhard Kuntscher's first cloverleaf design was introduced in the early 1940s, intramedullary nail geometry has become increasingly complex. Many design changes have been introduced, and these have had profound effects upon the mechanical performance of intramedullary devices, making them more versatile. The subset of long-bone fractures amenable to intramedullary fixation is expanding, largely because of these advancements in nail design. Selection of the appropriate nail and bone-nail construct for each fracture configuration requires a knowledge of basic biomechanical principles behind nail design and the implant-host interface. Appropriate clinical application of this knowledge not only ensures the best possible intramedullary fixation of long-bone fractures, but it also aids in avoiding some of the complications that may occur.

  4. Three phase bone scintigraphy with (99m)Tc-MDP and serological indices in detecting infection after internal fixation in malunion or nonunion traumatic fractures.

    Science.gov (United States)

    Yang, Fang; Yang, Zheng; Feng, Jin; Zhang, Lianna; Ma, Daqing; Yang, Jigang

    2016-01-01

    To evaluate the diagnostic efficacy of technetium-99m-methylene diphosphonate ((99m)Tc-MDP) three phase bone scintigraphy in detecting infection in malunion or nonunion traumatic fractures after internal fixation. One hundred and eighty four patients with malunion or nonunion fractures after internal fixation (130 men and 54 women; age range, 16-79 years) underwent (99m)Tc-MDP three phase bone scintigraphy (3PBS). They were divided into the infection group (n=96) and the control group without infection (n=88) based on the final diagnosis after operation. The sensitivity, specificity, accuracy, positive prediction value (PPV) and negative prediction value (NPV) were calculated and compared. All patients carried out other laboratory tests related to infection such as complete serum blood cells count, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). The (99m)Tc-MDP 3PBS for the blood flow phase showed sensitivity, specificity, accuracy, positive predictive value and negative predictive value, 91.7% (88/96), 72.7% (64/88), 82.6% (152/184), 78.6% (88/112) and 88.9% (64/72), respectively and for the blood pool phase, 93.8% (90/96), 61.4% (54/88), 78.3% (144/184), 72.6% (90/124) and 90.0% (54/60) respectively. The semiquantitative indices of the ratio between the abnormal and the normal region of interest (ROI), called by us the A/N ratio, for both blood flow and blood pool phases as estimated between the infection group and the control group were statistically different. It is the opinion of the authors that (99m)Tc-MDP 3PBS provided high predictive values in diagnosing infection in patients with malunion or nonunion traumatic fractures after internal fixation. The diagnostic value of blood flow and blood pool phases estimated of the 3PBS was better than the laboratory indices: white blood cell counts, CRP, and ESR.

  5. Bone-anchored hearing devices in children with unilateral conductive hearing loss: a patient-carer perspective.

    Science.gov (United States)

    Banga, Rupan; Doshi, Jayesh; Child, Anne; Pendleton, Elizabeth; Reid, Andrew; McDermott, Ann-Louise

    2013-09-01

    We sought to determine the outcome of implantation of a bone-anchored hearing device in children with unilateral conductive hearing loss. A retrospective case note analysis was used in a tertiary referral pediatric hospital to study 17 consecutive cases of pediatric patients with unilateral conductive hearing loss who were fitted with a bone-anchored hearing device between 2005 and 2010. The average age of the patients at the time of bone-anchored hearing device fitting was 10 years 6 months (range, 6 years 3 months to 16 years). Qualitative subjective outcome measures demonstrated benefit. The vast majority of patients reported improved social and physical functioning and improved quality of life. All 17 patients are currently using their bone-anchored hearing device on a daily basis after a follow-up of 6 months. This study has shown improved quality of life in children with unilateral hearing loss after implantation of their bone-anchored hearing device. There was a high degree of patient satisfaction and improvement in health status reported by children and/or carers. Bone-anchored hearing devices have an important role in the management of children with symptomatic unilateral hearing loss. Perhaps earlier consideration of a bone-anchored hearing device would be appropriate in selected cases.

  6. A biomechanical comparison of headless tapered variable pitch compression and ao cortical bone screws for fixation of a simulated midbody transverse fracture of the proximal sesamoid bone in horses.

    Science.gov (United States)

    Eddy, Alison L; Galuppo, Larry D; Stover, Susan M; Taylor, Kenneth T; Jensen, David G

    2004-01-01

    To compare mechanical properties and failure characteristics of 2 methods of fixation for repair of a transverse, midbody fracture of the proximal sesamoid bone (PSB): 4.5-mm AO cortical bone screw (AO) placed in lag fashion and 4/5-mm Acutrak (AT) self-compressing screw. An in vitro biomechanical evaluation of intact forelimb preparations and forelimb preparations with a simulated midbody PSB fracture stabilized by a bone screw. Sixteen paired and 8 unilateral cadaveric equine forelimbs. A midbody transverse osteotomy was created in the medial PSB of bilateral forelimbs of 8 equine cadavers. The osteotomized PSB in 1 forelimb from each cadaver was repaired with an AO screw. The osteotomized PSB in each contralateral limb was repaired with an AT screw. Eight unilateral intact control limbs were also studied. Mechanical properties were determined from axial compression, single cycle to failure, load-deformation curves. Failure characteristics were determined by evaluation of video images and radiographs. No statistically significant differences were found between repair groups. Both AO and AT groups had significantly lower mechanical properties than intact limbs except for stiffness. AO and AT constructs were mechanically comparable when used to stabilize a simulated midbody fracture of the medial PSB. Both constructs were mechanically inferior to intact limbs. Clinical Relevance- The AT screw should be considered for clinical use because of the potential for less soft tissue impingement and superior biocompatibility compared with the stainless-steel AO screw. However, postoperative external coaptation is necessary to augment initial fracture stability for either fixation method, and to maintain a standing metacarpophalangeal joint dorsiflexion angle between 150 degrees and 155 degrees.

  7. In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur.

    Science.gov (United States)

    Haffner-Luntzer, Melanie; Müller-Graf, Fabian; Matthys, Romano; Abaei, Alireza; Jonas, René; Gebhard, Florian; Rasche, Volker; Ignatius, Anita

    2017-11-14

    Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The amount of the different tissues in the callus provides important information on the fracture healing progress. Available in vivo techniques to longitudinally monitor the callus tissue development in preclinical fracture-healing studies using small animals include digital radiography and µCT imaging. However, both techniques are only able to distinguish between mineralized and non-mineralized tissue. Consequently, it is impossible to discriminate cartilage from fibrous tissue. In contrast, magnetic resonance imaging (MRI) visualizes anatomical structures based on their water content and might therefore be able to noninvasively identify soft tissue and cartilage in the fracture callus. Here, we report the use of an MRI-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice. The experiments demonstrated that the fixator and a custom-made mounting device allow repetitive MRI scans, thus enabling longitudinal analysis of fracture-callus tissue development.

  8. Bone status in rheumatoid arthritis assessed at peripheral sites by three different quantitative ultrasound devices

    DEFF Research Database (Denmark)

    Madsen, O R; Suetta, C; Egsmose, C

    2004-01-01

    Rheumatoid arthritis (RA) is characterized by periarticular and generalized loss of bone mass. Quantitative ultrasound (QUS) has been introduced as a method for the assessment of bone status and fracture risk. In this cross-sectional study bone status was assessed by QUS at different peripheral...... sites in 27 women with RA (mean disease duration 15 years) and in 36 healthy women matched for age, height and weight. Speed of sound (SOS, m/s), broadband ultrasound attenuation (BUA, dB/MHz) and stiffness of the calcaneus were assessed by a Lunar Achilles device. Amplitude-dependent SOS (Ad-SOS, m...... reduced in RA at most sites ( pcalcaneus and distal radius ( p

  9. 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

    Objective: To examine the objective and subjective outcome of a new transcutaneous bone conduction hearing device. Study Design: Prospective, consecutive case series. Patients: Twelve patients were implanted. Eight patients had a conductive/mixed (con/mix) hearing loss. Four had single sided...... to beneficial outcome. In Speech, Spatial and Qualities of Hearing Scale 12, ''quality of hearing'' scored especially high. The con/mix hearing loss group showed larger benefit especially in SDS, SRT50% in noise and the subjective evaluations, whereas frequency and duration of use were similar. Conclusion......: This study on the first 12 Nordic patients implanted with a new transcutaneous bone conduction hearing device demonstrates significant objective, as well as subjective hearing benefit. Patient satisfaction was high, as was the frequency of use....

  10. Ipsilateral Femoral Fracture Non-Union and Delayed Union Treated By Hybrid Plate Nail Fixation and Vascularized Fibula Bone Grafting: A Case Report

    Directory of Open Access Journals (Sweden)

    CK Chan

    2013-07-01

    Full Text Available Non-union is a well recognized complication of femoral neck fractures. The decision whether to attempt fracture fixation or to resort to hip replacement is particularly difficult in patients in the borderline age group in whom complex attempts at gaining union may fail and later present a difficult revision. On the other hand the patient may be young enough that arthroplasty best be avoided . Besides, presence of ipsilateral femoral shaft fracture with delayed union in addition to the femoral neck non-union will pose major problems at operation. We share our experience in treating a femoral neck fracture non-union with ipsilateral femoral shaft delayed union in the shaft and in the distal femur in a fifty years old patient. The fracture was treated with an angle blade plate and supracondylar nail supplemented with a free vascularised fibular bone grafting and autologous cancellous graft. There was radiological union at fourth month. At sixth months, the patient was free of pain and able to walk without support. Thus, we would like to suggest that vascularised fibula bone grafting with supracondylar nailing is a viable option for this pattern of fracture.

  11. 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

  12. Intraosseous fixation compared to plantar plate fixation for first metatarsocuneiform arthrodesis: a cadaveric biomechanical analysis.

    Science.gov (United States)

    Roth, Klaus Edgar; Peters, Jennifer; Schmidtmann, Irene; Maus, Uwe; Stephan, Daniel; Augat, Peter

    2014-11-01

    Metatarsocuneiform (MTC) fusion is a treatment option for management of hallux valgus. We compared the biomechanical characteristics of an internal fixation device with plantar plate fixation. Seven matched pairs of feet from human cadavers were used to compare the intramedullary (IM) device plus compression screw to plantar plate combined with a compression screw. Specimen constructs were loaded in a cyclic 4-point bending test. We obtained initial/final stiffness, maximum load, and number of cycles to failure. Bone mineral density was measured with peripheral quantitative computed tomography. Performance was compared using time to event analysis with number of cycles as time variable, and a proportional hazard model including shared frailty model fitted with treatment and bone mineral density as covariates. On average the plates failed after 7517 cycles and a maximum load of 167 N, while the IM-implants failed on average after 2946 cycles and a maximum load of 69 N. In all pairs the 1 treated with IM-implant failed earlier than the 1 treated with a plate (hazard ratio for IM-implant versus plate was 79.9 (95% confidence interval [6.1, 1052.2], P = .0009). The initial stiffness was 131 N/mm for the plantar plate and 43.3 N/mm for the IM implant. Initial stiffness (r = .955) and final stiffness (r = .952) were strongly related to the number of cycles to failure. Bone mineral density had no effect on the number of cycles to failure. Plantar plate fixation created a stronger and stiffer construct than IM fixation. A stiffer construct can reduce the risk of nonunion and shorten the period of non-weight-bearing. © The Author(s) 2014.

  13. 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

    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......, implant positioning, and quality of reduction. From a questionnaire completed during admission, 2 variables for comorbidity and walking disability were chosen. Primary outcome was low hip BMD (amount of mineral matter per square centimeter of hip bone) compared to hip failure (resection, arthroplasty...

  14. [Carbon external fixator--CARBOELASTOFIX in treatment of tibia diaphysis fractures].

    Science.gov (United States)

    Ambroziak, Maciej; Górecki, Andrzej; Purski, Karol; Zgoda, Marcin; Kawalec, Krzysztof

    2007-01-01

    The authors presents the results of healing status of tibia diaphysis fractures treated with carbon-plate fixator on a group of 12 patients (9 men and 3 women with age between 27 and 89 years). Long-term mechanical investigations and studies at animals, performed at our Department have shown advantages of bone fixation performed with a new device for osteosynthesis, called by authors CARBOELASTOFIX. General principle of the method is the use of external fixation device, made of carbon-epoxide resin composite plates with variable flexibility, enabling hastened fracture healing. The research allowed also to work out the guidelines of indications for surgery, surgical technique and method of modifying flexibility of fixation consistently with fracture healing course. The mean time of observation (from the operation to the healing) was 23 weeks, having 10 good and 2 bad results.

  15. A minimally invasive technique for the implantation of bone-anchored hearing devices.

    Science.gov (United States)

    Wilson, David F; Kim, Harold H

    2013-09-01

    To describe and evaluate a novel technique for the implantation of bone conduction hearing devices as compared with a common, conventional technique. Case series with chart review. Tertiary referral otology and neurotology practice. Individuals who underwent the implantation of bone-anchored hearing devices between January 1, 2004, and December 31, 2011, were identified. Demographic data, surgical indications, surgical technique used, surgical time, and complications were recorded. Soft tissue complications were graded on the Holgers classification scheme. Group 1 was defined as those undergoing a traditional technique using a dermatome with subcutaneous tissue reduction. Group 2 was defined as those undergoing the described technique for implantation of the coupling hardware with minimal subcutaneous soft tissue reduction. Forty patients underwent the procedure, with 11 patients comprising group 1 and 29 patients comprising group 2. Group 2 required a shorter operative time (32.3 vs 56.1 minutes, P bone-anchored hearing devices using the described technique that necessitated minimal soft tissue reduction.

  16. 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

  17. One versus two titanium screw fixation of autologous onlay bone grafts in the anterior maxilla: a randomised histological pilot study

    NARCIS (Netherlands)

    Burger, Evita A. C.; Meshkini, Hamid; Lindeboom, Jerome A. H.

    2011-01-01

    The aim of this study was to compare the histological presentation of local mandibular bone grafts fixed with one screw or two screws in buccal anterior maxillary augmentation procedures. Local buccal defects of the anterior maxilla were reconstructed in 12 patients (mean age 47 ± 17 years, range 18

  18. Surgical management of diaphyseal humeral nonunion after intramedullary nailing: Wave-plate fixation and autologous bone grafting without nail removal

    NARCIS (Netherlands)

    Gerber, Ariane; Marti, René; Jupiter, Jesse

    2003-01-01

    Six patients with a nonunion of the humeral diaphysis after intramedullary nailing were treated with a wave plate and autologous bone graft but without removal of the intramedullary implant. The mean duration of the nonunion was 19 months (range, 6-36 months). At a mean follow-up of 12 months

  19. Audiological and subjective benefit results in bone-anchored hearing device users.

    Science.gov (United States)

    Boleas-Aguirre, Maria Soledad; Bulnes Plano, Maria Dolores; de Erenchun Lasa, Iñigo Ruiz; Ibáñez Beroiz, Berta

    2012-06-01

    Audiological and subjective benefits in adult bone-anchored hearing device users. Retrospective evaluation. Tertiary referral center. Thirty-eight adult subjects fitted with unilateral bone-anchored hearing device. Audiometric measurements included sound-field pure-tone and speech audiometries (speech reception threshold, maximum speech discrimination). Subjective benefit was assessed by the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire. Ipsilateral and contralateral hearing loss was considered. Comparison was drawn between Compact, Divino, and Intenso processors. To compare sound-field pure-tone and speech audiometries and APHAB results with and without the device adjusted for the unaided results. With the device, sound-field pure-tone audiometry results revealed an increase gain in all frequencies. Sound-field speech audiometry showed that the mean threshold of speech recognition was 20 dB lower, maximum discrimination was attained at 5 dB less, and percentage of maximum discrimination increased by 5%. Scores in the APHAB questionnaire decreased except for the aversiveness subscale. Auditory-adjusted gain showed greater benefit in subjects with ipsilateral conductive hearing loss.Subjects with contralateral normal hearing or conductive hearing loss showed greater improvement that those with contralateral mixed or sensorineural hearing loss. There were no differences between Compact, Divino and Intenso processors. When comparisons are adjusted for unaided condition, the bone-anchored hearing device provided auditory and subjective benefit in subjects with ipsilateral conductive hearing loss and contralateral normal hearing or conductive hearing loss. It gave marginal benefit in ipsilateral mixed and contralateral mixed or sensorineural hearing loss. No differences were found between the Compact, Intenso, and Divino processors.

  20. Screw fixation via diploic bone paralleling to occiput table: anatomical analysis of a new technique and report of 11 cases.

    Science.gov (United States)

    Mingsheng, Tan; Huimin, Wang; Xin, Jiang; Ping, Yi; Hongyu, Wei; Feng, Yang; Wu, Wang; Guangbo, Zhang

    2007-12-01

    Several types of posterior approaches have been adopted for occipitocervical fusion. Prior to this study, Foerater et al. in 1927 used a fibular strut graft in the site between the occiput and the lower cervical spine to achieve fusion. Since then, various techniques including wrings, Hartshill loop, AO reconstructive plate, and AXIS occipital plate were described and used widely. As far as we know, all these techniques involve the screw placement vertical to the diploic bone; however none has ever addressed the feasibility of screw placement in occiput parallelling to the diploic bone. In our study, 30 dry specimens of human occiputs were measured manually using vernier calipers and protractors. The intradiploic screw was first supposed to be inserted inferiorly to the superior nuchal line (SNL) prominence. The entry point located at the superior edge of the SNL prominence. Afterward, the measurements of extracranial occiput in SNL area on midline and bilateral 15 mm to the midline saggital-cutting planes of the occiput were conducted. The thickness of the occipital bone at the location of SNL prominence, the entry point, the exit point and the screw orientation were measured, respectively. Afterward, 11 patients with craniocervical malformation were treated surgically using this alternative and their X-ray radiographs and CT scans were evaluated postoperatively. The data showed that the occipital at the site of SNL prominence was the thickest. The thickest point was external occipital protuberance (EOP), which was up to 14 mm. The thickness decreased gradually from the site of SNL to the superior border of surgical decompressed area. The actual length of screw channel was about 26 mm. The mean thickness for safe screw insertion ranged from 5.73 to 14.14 mm. A total of 22 intraocciput screws parallel to diploic bone were placed precisely, without injury to the cerebral and inner occipital venous sinus. The results confirm that occiput is available for holding

  1. Flexible fixation and fracture healing

    DEFF Research Database (Denmark)

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

    2011-01-01

    External and internal fixators use bone screws that are locked to a plate or bar to prevent periosteal compression and associated impairment of blood supply. Both osteosynthesis techniques rely on secondary bone healing with callus formation with the exception of compression plating of simple...

  2. Innovation in abutment-free bone-anchored hearing devices in children: Updated results and experience.

    Science.gov (United States)

    Baker, Shaun; Centric, Aaron; Chennupati, Sri Kiran

    2015-10-01

    Bone-anchored hearing devices are an accepted treatment option for hearing restoration in various types of hearing loss. Traditional devices have a percutaneous abutment for attachment of the sound processor that contributes to a high complication rate. Previously, our institution reported on the Sophono (Boulder, CO, USA) abutment-free system that produced similar audiologic results to devices with abutments. Recently, Cochlear Americas (Centennial, CO, USA) released an abutment-free bone-anchored hearing device, the BAHA Attract. In contrast to the Sophono implant, the BAHA Attract utilizes an osseointegrated implant. This study aims to demonstrate patient benefit abutment-free devices, compare the results of the two abutment-free devices, and examine complication rates. A retrospective chart review was conducted for the first eleven Sophono implanted patients and for the first six patients implanted with the BAHA Attract at our institution. Subsequently, we analyzed patient demographics, audiometric data, clinical course and outcomes. Average improvement for the BAHA Attract in pure-tone average (PTA) and speech reception threshold (SRT) was 41dB hearing level (dBHL) and 56dBHL, respectively. Considering all frequencies, the BAHA Attract mean improvement was 39dBHL (range 32-45dBHL). The Sophono average improvement in PTA and SRT was 38dBHL and 39dBHL, respectively. The mean improvement with Sophono for all frequencies was 34dBHL (range 24-43dBHL). Significant improvements in both pure-tone averages and speech reception threshold for both devices were achieved. In direct comparison of the two separate devices using the chi-square test, the PTA and SRT data between the two devices do not show a statistically significant difference (p-value 0.68 and 0.56, respectively). The complication rate for these abutment-free devices is lower than that of those featuring the transcutaneous abutment, although more studies are needed to further assess this potential advantage

  3. 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.

  4. Acetabular reconstruction with human and bovine freeze-dried bone grafts and a reinforcement device

    Directory of Open Access Journals (Sweden)

    Ricardo Rosito

    2008-01-01

    Full Text Available BACKGROUND: This is a cohort trial (1997-2005 of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG and a reinforcement device. OBJECTIVE: To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS: There were two groups: I (n=26 receiving human grafts and II (n=25 receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d'Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn's et al. criteria for radiographic bone incorporation. RESULTS: No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5% and 76% of graft incorporation (p=0.424. CONCLUSION: The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty.

  5. Histopathological examination of bone debris from reaming of interlocking intra-medullary nail fixation of long bone fractures with concomitant head injury.

    Science.gov (United States)

    Khallaf, Fathy G; Kehinde, Elijah O

    2015-12-01

    The aim of study was to test, for the presence of osteoblasts in the reaming debris of intramedullary nailing of femoral and tibial fracture in patients with and without severe head injury. Two groups of patients were studied. Group A (n = 32) had long bone fractures in addition to having head injuries. Group B (n = 35) had only long bone fractures. The fractures in the 2 groups of patients was treated by inter medullary nailing. Osteoblasts in the debris of the inter medullary nailing was compared between the 2 groups of patients. The results demonstrated that histopathological specimens from reaming debris of fractured femur and tibia in patients with head injury showed osteoblasts in (82.9%) and in (27.5%) of patients with isolated long bone fractures (p fractures and concomitant head injury confirm fast and adequate healing in these patients and the presence of plenty of osteoblasts in their reaming debris may reflect a proof of accelerated fracture healing environment.

  6. 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....

  7. Bilateral bone conduction devices: improved hearing ability in children with bilateral conductive hearing loss.

    Science.gov (United States)

    Dun, Catharina A J; Agterberg, Martijn J H; Cremers, Cor W R J; Hol, Myrthe K S; Snik, Ad F M

    2013-01-01

    The aim of the study was to investigate whether children with bilateral conductive hearing loss benefit from their second device (i.e., the bilateral bone conduction device [BCD]). Speech recognition in noise was assessed in 10 children fitted with bilateral BCDs during childhood. Speech recognition was measured in 2 conditions with both BCDs active. Spatial resolution was tested with the Minimum Audible Angle test in the bilateral and monaural listening conditions. Children demonstrated an improvement in speech recognition when speech was presented from the front and noise was presented from the right-hand side as compared with both speech and noise being presented from the front. The minimum audible angle decreased from 57° in the best monaural condition to 13° in the bilateral condition. The audiological outcomes demonstrate the advantage of bilateral BCD fitting in children with bilateral conductive hearing loss.

  8. Residual position errors of lymph node surrogates in breast cancer adjuvant radiotherapy: Comparison of two arm fixation devices and the effect of arm position correction

    International Nuclear Information System (INIS)

    Kapanen, Mika; Laaksomaa, Marko; Skyttä, Tanja; Haltamo, Mikko; Pehkonen, Jani; Lehtonen, Turkka; Kellokumpu-Lehtinen, Pirkko-Liisa; Hyödynmaa, Simo

    2016-01-01

    Residual position errors of the lymph node (LN) surrogates and humeral head (HH) were determined for 2 different arm fixation devices in radiotherapy (RT) of breast cancer: a standard wrist-hold (WH) and a house-made rod-hold (RH). The effect of arm position correction (APC) based on setup images was also investigated. A total of 113 consecutive patients with early-stage breast cancer with LN irradiation were retrospectively analyzed (53 and 60 using the WH and RH, respectively). Residual position errors of the LN surrogates (Th1-2 and clavicle) and the HH were investigated to compare the 2 fixation devices. The position errors and setup margins were determined before and after the APC to investigate the efficacy of the APC in the treatment situation. A threshold of 5 mm was used for the residual errors of the clavicle and Th1-2 to perform the APC, and a threshold of 7 mm was used for the HH. The setup margins were calculated with the van Herk formula. Irradiated volumes of the HH were determined from RT treatment plans. With the WH and the RH, setup margins up to 8.1 and 6.7 mm should be used for the LN surrogates, and margins up to 4.6 and 3.6 mm should be used to spare the HH, respectively, without the APC. After the APC, the margins of the LN surrogates were equal to or less than 7.5/6.0 mm with the WH/RH, but margins up to 4.2/2.9 mm were required for the HH. The APC was needed at least once with both the devices for approximately 60% of the patients. With the RH, irradiated volume of the HH was approximately 2 times more than with the WH, without any dose constraints. Use of the RH together with the APC resulted in minimal residual position errors and setup margins for all the investigated bony landmarks. Based on the obtained results, we prefer the house-made RH. However, more attention should be given to minimize the irradiation of the HH with the RH than with the WH.

  9. Intermediate outcomes of a transcutaneous bone conduction hearing device in a paediatric population.

    Science.gov (United States)

    Dimitriadis, Panagiotis A; Carrick, Suzanne; Ray, Jaydip

    2017-03-01

    The aim of this study was to review the outcomes of Bone Anchored Hearing Aid (BAHA ® ) Attract implantation in a cohort of paediatric patients. Prospective data collection and case review were undertaken in a paediatric tertiary referral centre. We have included patients under the age of 16 years with unilateral or bilateral hearing loss that met the criteria for BAHA ® Attract implantation. The main outcome measures were surgical complications and Patient Reported Outcomes including the 'Speech, Spatial and Qualities of Hearing scale' (SSQ-12) and 'Qualitative Feedback for BAHA ® 5 Hearing Aids'. Twenty-five paediatric patients were implanted with the BAHA ® Attract between June 2014 and July 2016. Nine of them had a conversion from a percutaneous Bone Conduction Hearing Device (BCHD). Four children had minor skin problems that settled with conservative measures. Two children with a previous percutaneous BCHD developed skin dehiscence over the magnet after conversion to the transcutaneous version. The SSQ-12 was completed by 6 children and an improvement of 22% was noted between the unaided and aided condition. The patients and their parents were generally satisfied with the BAHA ® Attract. The BAHA ® Attract offers a good solution for hearing rehabilitation in appropriately selected and counseled patients. The complication rate was low for primary surgery but higher in cases of conversion from a percutaneous device. Large, prospective data is needed to evaluate the relative risks and benefits of this BCHD. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Arthroscopic Reduction and Fixation of Tibial Spine Avulsion Fractures by a Stainless Steel Wiring Technique.

    Science.gov (United States)

    Abdelhamid, Mohamed M; Bayoumy, Maysara Abdelhalim; Elkady, Hesham A; Abdelkawi, Ayman Farouk

    2017-12-01

    Several techniques of arthroscopic treatment of tibial spine avulsion fractures have been described in the literature. These techniques include the use of various fixation devices such as screws, K-wires, wiring, sutures, and suture anchors. In this study, we evaluate a new wiring technique for the treatment of these injuries. This technique involves fixation by stainless steel tension wires passed over the fractured spine and tied over a bone bridge. The advantages of this technique are that it aids in reduction, allows for compression of the tibial spine fragment anatomically in its fracture bed, provides stable fixation in difficult comminuted fractures, and allows for early mobilization and weight bearing because of the solid fixation.

  11. Feasibility study of a non-invasive eye fixation and monitoring device using a right-angle prism mirror for intensity-modulated radiotherapy for choroidal melanoma.

    Science.gov (United States)

    Inoue, Toshihiko; Masai, Norihisa; Shiomi, Hiroya; Oh, Ryoong-Jin; Uemoto, Kenji; Hashida, Noriyasu

    2017-05-01

    We aimed to describe the feasibility and efficacy of a novel non-invasive fixation and monitoring (F-M) device for the eyeballs (which uses a right-angle prism mirror as the optic axis guide) in three consecutive patients with choroidal melanoma who were treated with intensity-modulated radiotherapy (IMRT). The device consists of an immobilization shell, a right-angle prism mirror, a high magnification optical zoom video camera, a guide lamp, a digital voice recorder, a personal computer, and a National Television System Committee standard analog video cable. Using the right-angle prism mirror, the antero-posterior axis was determined coincident with the optic axis connecting the centers of the cornea and pupil. The axis was then connected to the guide light and video camera installed on the couch top on the distal side. Repositioning accuracy improved using this method. Furthermore, the positional error of the lens was markedly reduced from ±1.16, ±1.68 and ±1.11 mm to ±0.23, ±0.58 and ±0.26 mm in the horizontal direction, and from ±1.50, ±1.03 and ±0.48 mm to ±0.29, ±0.30 and ±0.24 mm in the vertical direction (Patient #1, #2 and #3, respectively). Accordingly, the F-M device method decreased the planning target volume size and improved the dose-volume histogram parameters of the organ-at-risk via IMRT inverse planning. Importantly, the treatment method was well tolerated. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  12. 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.

  13. Completely-in-the-canal magnet-drive hearing device: a temporal bone study.

    Science.gov (United States)

    Mahboubi, Hossein; Malley, Melinda J D; Paulick, Peyton; Merlo, Mark W; Bachman, Mark; Djalilian, Hamid R

    2013-03-01

    The magnet-drive hearing device (MHD) is a small completely-in-the-canal hearing aid prototype that drives the tympanic membrane (TM) through a magnetic interface. A cadaveric temporal bone was prepared. The MHD was coupled to a nickel-epoxy pellet glued to the umbo. Frequency sweeps between 0.3 and 10 kHz were performed, and the MHD was driven with various levels of current. Displacements of the posterior crus of the stapes were measured using a laser Doppler vibrometer and compared with sound-induced displacements. The MHD had a linear frequency response and low total harmonic distortion. The pellet placement altered the stapes movements; however, the changes were statistically insignificant. Inputs of 100 and 300 mV produced displacements equivalent to those of the natural sound at 70- and 80-dB sound pressure level, respectively. The coupling of this novel device using a magnetic interface to the umbo had a frequency output wider than air conduction devices, and its actuator was effective in driving the TM.

  14. A new transcutaneous bone anchored hearing device - the Baha® Attract System: the first experience in Turkey.

    Science.gov (United States)

    Işeri, Mete; Orhan, Kadir Serkan; Kara, Ahmet; Durgut, Merve; Oztürk, Murat; Topdağ, Murat; Calışkan, Sebla

    2014-01-01

    In this study, we reported our experience with a new transcutaneous bone conduction hearing device, the Baha® Attract System. This multi-center clinical study included the first 12 patients (8 females, 4 males; mean age 27.6 years; range 5 to 65 years) in whom a new transcutaneous bone conduction system was implanted in Turkey. The mean air-bone gap was 41 dB. Bone smoothing around the implant was needed in five patients. We placed a sound processor in the fourth postoperative week for all patients. Our study results suggest that the new bone conduction implant is promising for the patients with conductive or mixed hearing loss who are unable to wear conventional air conduction hearing aid and comparable to percutaneous systems.

  15. Open reduction and cranial bone plate fixation of fractures involving the distal aspect of the radius and ulna in miniature- and toy-breed dogs: 102 cases (2008-2015).

    Science.gov (United States)

    De Arburn Parent, Rebecca; Benamou, Jérôme; Gatineau, Matthieu; Clerfond, Pierre; Planté, Jérôme

    2017-06-15

    OBJECTIVE To determine outcomes and complication rates of open reduction and cranial bone plate fixation of fractures involving the distal aspect of the radius and ulna in miniature- and toy-breed dogs. DESIGN Retrospective case series. ANIMALS 102 miniature- and toy-breed dogs (105 fractures) weighing ≤ 7 kg (15.4 lb) that had undergone open reduction and cranial bone plate fixation of a fracture involving the distal aspect of the radius and ulna from 2008 through 2015. PROCEDURES Medical records were reviewed and information extracted regarding dog and fracture characteristics, surgical variables, and follow-up examination data (including postoperative complications). Postoperative radiographs were examined for distal fragment size, implant placement, apposition, alignment, and healing stage. A long-term follow-up questionnaire was completed by telephone interview with dog owners at least 6 months after surgery. RESULTS Mean length of the distal bone fragment in all fractures was 19.2 mm, with a mean distal-to-total radial length ratio of 0.21. At last follow-up examination (typically 6 weeks after surgery), 97 (95%) dogs had no signs of lameness; minor lameness was identified in 5 (5%) dogs. Complications developed in 26 (25%) fractures (23 [22%] minor and 3 [3%] major complications). Sixty-eight of 71 (96%) owners rated the overall and long-term outcome as excellent and 3 (4%) as good; 68 of 71 (96%) dogs reportedly had no signs of residual lameness. CONCLUSIONS AND CLINICAL RELEVANCE Open reduction and cranial bone plate fixation for the treatment of radius-ulna fractures in miniature- and toy-breed dogs provided an excellent outcome with a low complication rate.

  16. 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.

  17. The use of a point of care device for monitoring the bone resorption biomarker urinary N-telopeptide in cancer patients with bone metastases.

    Science.gov (United States)

    Lester, Jim E; Brown, Janet E; Hannon, Rosemary A; Ellis, Sue P; Horsman, Janet M; Purohit, Omprakash P; Coleman, Robert E

    2010-03-01

    Type I collagen is the major constituent of bone and its breakdown products are increasingly used as sensitive markers of bone resorption. The N-terminal peptide-bound crosslinks of type I collagen (NTX) can be measured in urine and is useful for the monitoring of patients with metastatic bone disease. Studies have shown that raised NTX levels in metastatic bone disease correlate with an increased risk of complications and pathological fracture. The development of accurate and instantaneous point of care devices (POCD) would facilitate patient treatment and avoid delays in awaiting results from specialist laboratories. This study assesses the clinical performance of a single use POCD (OSTEOMARK NTx Point of Care Rx Home Use) to monitor NTX levels in patients with metastatic bone disease. NTX was measured in duplicate in 136 urine samples from patients attending clinic with metastatic bone disease using the POCDs. In our centre the frequency of bisphosphonate treatment is dependent on the NTX level, which is categorised into three groups (0-50, 50-100 and >100 nmol BCE/mmol creatinine). We used these categories to compare the clinical performance of the POCDs to that of a laboratory immunoassay. From a total of 272 devices, 231 (84.9%) successfully recorded a value in nM BCE/mM creatinine. Statistical analysis of the measure of agreement between POCD and laboratory assay found moderate agreement between the two assays (kappa 0.508). Out of the 72 samples with a laboratory assay value of 100, 19 (95.0%) were found to be within the same category using POCDs. The measurement of urinary NTX by POCD appears to be a viable option for the monitoring of metastatic cancer patients. Whilst POCDs appear to record higher values than laboratory assays, the correlation between devices is good and with further research the NTX categories could be modified to accommodate this variation.

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

    Science.gov (United States)

    Jahadakbar, Ahmadreza; Shayesteh Moghaddam, Narges; Amerinatanzi, Amirhesam; Dean, David; Karaca, Haluk E.; Elahinia, Mohammad

    2016-01-01

    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. PMID:28952598

  19. 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.

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

    Science.gov (United States)

    Jahadakbar, Ahmadreza; Shayesteh Moghaddam, Narges; Amerinatanzi, Amirhesam; Dean, David; Karaca, Haluk E; Elahinia, Mohammad

    2016-12-19

    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.

  1. Femoral Reconstruction Using External Fixation

    Directory of Open Access Journals (Sweden)

    Yevgeniy Palatnik

    2011-01-01

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

  2. Better performance with bone-anchored hearing aid than acoustic devices in patients with severe air-bone gap

    NARCIS (Netherlands)

    Wolf, M.J. de; Hendrix, S.; Cremers, C.W.R.J.; Snik, A.F.M.

    2011-01-01

    OBJECTIVES/HYPOTHESIS: A study performed in the 1990s with analogue linear hearing aids showed that in patients with mixed hearing loss and an air-bone gap that exceeded 25 to 30 dB, speech perception was better with a bone-anchored hearing aid (Baha) than with a conventional behind-the-ear (BTE)

  3. 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.

  4. Integration of Rabbit Adipose Derived Mesenchymal Stem Cells to Hydroxyapatite Burr Hole Button Device for Bone Interface Regeneration

    Directory of Open Access Journals (Sweden)

    Viswanathan Gayathri

    2016-01-01

    Full Text Available Adipose Derived Mesenchymal Stem Cells, multipotent stem cells isolated from adipose tissue, present close resemblance to the natural in vivo milieu and microenvironment of bone tissue and hence widely used for in bone tissue engineering applications. The present study evaluates the compatibility of tissue engineered hydroxyapatite burr hole button device (HAP-BHB seeded with Rabbit Adipose Derived Mesenchymal Stem Cells (ADMSCs. Cytotoxicity, oxidative stress response, apoptotic behavior, attachment, and adherence of adipose MSC seeded on the device were evaluated by scanning electron and confocal microscopy. The results of the MTT (3-(4,5-dimethylthiazol-2,5-diphenyl tetrazolium bromide assay indicated that powdered device material was noncytotoxic up to 0.5 g/mL on cultured cells. It was also observed that oxidative stress related reactive oxygen species production and apoptosis on cell seeded device were similar to those of control (cells alone except in 3-day period which showed increased reactive oxygen species generation. Further scanning electron and confocal microscopy indicated a uniform attachment of cells and viability up to 200 μm deep inside the device, respectively. Based on the results, it can be concluded that the in-house developed HAP-BHB device seeded with ADMSCs is nontoxic/safe compatible device for biomedical application and an attractive tissue engineered device for calvarial defect regeneration.

  5. Superconstructs in the treatment of charcot foot deformity: plantar plating, locked plating, and axial screw fixation.

    Science.gov (United States)

    Sammarco, V James

    2009-09-01

    Management of Charcot's deformity of the foot and ankle continues to challenge physicians. Medical co-morbidity, peripheral neuropathy, vascular disease, and immune impairment cause severe problems for these patients and, when combined with neuroarthropathy, can lead to amputation. Progressive bony deformity and bone resorption, which may accompany neuroarthropathy, only increase the challenge of surgical treatment. These challenges have led physicians to develop "superconstruct" techniques to improve fixation, whereby fusion is extended beyond the zone of injury to include joints that are not affected, bone resection is performed to shorten the extremity to allow for adequate reduction of deformity without undue tension on the soft tissue envelope, the strongest device is used that can be tolerated by the soft tissue envelope; and the devices are applied in a novel position that maximizes mechanical function. This article reviews three techniques designed to achieve lasting deformity correction and successful arthrodesis: plantar plating, locked plating, and axial screw fixation.

  6. Long-term Compliance and Satisfaction With Percutaneous Bone Conduction Devices in Patients With Congenital Unilateral Conductive Hearing Loss

    NARCIS (Netherlands)

    Nelissen, R.C.; Mylanus, E.A.M.; Cremers, C.W.R.J.; Hol, M.K.S.; Snik, A.F.M.

    2015-01-01

    OBJECTIVE: Patients with congenital unilateral conductive hearing loss (UCHL) can either be watchful monitored or treated surgically through the fitting of a percutaneous bone conduction device (BCD) or, in some cases, atresia repair. The current study evaluated the long-term compliance and

  7. 21 CFR 888.3020 - Intramedullary fixation rod.

    Science.gov (United States)

    2010-04-01

    ... of alloys such as cobalt-chromium-molybdenum and stainless steel. It is inserted into the medullary (bone marrow) canal of long bones for the fixation of fractures. (b) Classification. Class II. ...

  8. Functional treatment of skeletal Class II malocclusion using bone-anchored devices and intermaxillary elastics

    Directory of Open Access Journals (Sweden)

    Mahmood Reza Kalantar Motamedi

    2015-01-01

    Full Text Available Introduction: Dentofacial functional appliances used for the treatment of skeletal Class II malocclusion are divided into two groups: Removable appliances and fixed (bonded appliances, each with certain advantages and disadvantages. Considering the problems related to functional appliances such as high volume in the oral cavity, patient noncompliance, esthetics, tissue irritation or ulceration, speech or breathing difficulties, etc., there is considerable demand to develop a new appliance that can overcome these issues. Thus, the aim of the current study is to present a hypothesis regarding a new functional treatment technique. The hypothesis: We hypothesize that by fixing mini-plates or -implants in the posterior region of the mandible and the anterior part of the infrazygomatic crest region of the maxilla using intermaxillary elastics, we can expect a forward growth of the mandible in a growing child. Using this technique, the force vector will be in the oblique (forward-upward direction. By installing mini-plates with a long connecting bar in the infrazygomatic crest region (with the orthodontic attachment head approximating the level of the occlusal plane, and mini-plates or -implants in the most posterior and superior regions of the mandible, such as the retromolar region, the force vector can be placed in the most horizontal direction possible. Evaluation of the hypothesis: In the literature, significant growth modification results were reported in skeletal Class III patients using intermaxillary elastics and bone-anchored devices fixed in both jaws, when compared with those in the nontreatment group. Therefore, in practice, intermaxillary elastics can produce enough traction to stimulate the bone to change and grow. Thus, we presume that inverting the direction of the force vector (i.e., posterior-anterior force may have similar growth effects on the mandibles of growing children.

  9. 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.

  10. Fixation of distal fibular fractures: A biomechanical study of plate fixation techniques.

    Science.gov (United States)

    Marvan, Jiri; Horak, Zdenek; Vilimek, Miloslav; Horny, Lukas; Kachlik, David; Baca, Vaclav

    2017-01-01

    Ankle fractures are complex injuries with variable prognoses that depend upon many factors. The aim of the treatment is to restore the ankle joint biomechanical stability with maximum range of motion. Most ankle fractures are fibular fractures, which have a typical oblique fracture line in the distal fibula located in the area of the tibiofibular syndesmosis. The aim of this study was to simulate numerically several fixation techniques of the distal fibular fractures, evaluate their stability, determine their impact on surrounding tissue load, and correlate the results to clinical treatment experience. The following three models of fibular fracture fixation were used: (a) plate fixation with three screws attached above/below and lag screws, (b) plate fixation with two screws attached above/below and lag screws, and (c) three lag screws only. All three fracture fixation models were analyzed according to their use in both healthy physiological bone and osteoporotic bone tissue. Based on the results of Finite Element Analysis for these simulations, we found that the most appropriate fixation method for Weber-B1 fibular fractures was an unlocked plate fixation using six screws and lag screws, both in patients with physiological and osteoporotic bone tissue. Conversely, the least appropriate fixation method was an unlocked plate fixation with four screws and lag screws. Although this fixation method reduces the stress on patients during surgery, it greatly increased loading on the bone and, thus, the risk of fixation failure. The final fixation model with three lag screws only was found to be appropriate only for very limited indications.

  11. An evaluation of the quality of evidence available to inform current bone conducting hearing device national policy.

    Science.gov (United States)

    Mandavia, R; Carter, A W; Haram, N; Mossialos, E; Schilder, A G M

    2017-10-01

    In 2016, NHS England published the commissioning policy on Bone Conducting Hearing Devices (BCHDs). This policy was informed by updated evidence on the clinical and cost-effectiveness of BCHDs as well as by the 2013 Bone Anchored Hearing Aid (BAHA) policy. Commissioning policies set the criteria for service delivery and therefore have a major impact on the care received by patients. It is important that stakeholders have a good appreciation of the available evidence informing policy, as this will promote engagement both with the policy and with future research leading on from the policy. In this article, we provide stakeholders with a transparent and pragmatic assessment of the quality of the body of evidence available to inform current BCHD national policy. (i) A systematic review of the literature on BCHDs published since the development of the 2013 policy was performed in September 2016, adhering to PRISMA recommendations. The search terms used were as follows bone conduction; bone conducting; bone anchor; BAHA; Bone Anchored Hearing Aid; Bone Conducting Hearing Device; BCHD; Bone Conducting Hearing Implant; BCHI; Sophono; Bonebridge; Soundbite; Ponto; Hearing aid; implant; device; hearing device. Publications that could inform current BCHD policy were included. The quality of included articles was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. (ii) The quality of evidence referenced by the 2013 BAHA policy was assessed using the GRADE system. (i) Of the 2576 publications on BCHDs identified by the systematic search, 39 met the inclusion criteria for further analysis. Using the GRADE criteria, the quality of evidence was classified as of 'very low quality'. (ii) The 2013 BAHA policy was informed by 14 references. The GRADE system classifies the quality of evidence that informed the policy as of 'very low quality'. The GRADE system defines the body of evidence available to inform current national BCHD policy

  12. Biomechanical analysis of titanium fixation plates and screws in ...

    African Journals Online (AJOL)

    Conclusions: It was concluded that the use of double 4-hole straight plates provided the sufficient stability on the osteotomy site when compared with the other rigid fixation methods used in this study. Key words: Bone plates, bone screws, finite element analysis, jaw fixation techniques, mandible, mandibular osteotomy ...

  13. Influence of Behavior on Complications of Osseointegrated Bone Conduction Devices in Children.

    Science.gov (United States)

    Kubala, Michael E; Cox, Matthew D; Nelson, Kurt L; Richter, Gresham T; Dornhoffer, John L

    2017-04-01

    Compare incidences of complications following implantation of osseointegrated bone conduction devices (OBCD) between children with and without behavioral disorders. Case series with chart review. Tertiary referral center otology and neurotology practice. Pediatric patients who underwent implantation of OBCD between May 2009 and July 2014 at Arkansas Children's Hospital. Implantation with Cochlear BAHA 200 series, Cochlear BAHA BI300, or Oticon OBCD. Osseointegration failure (OIF) with resulting loss of flange-fixture and/or skin and soft tissue reactions. The total rate of complications was 66.2%, with the majority being minor complications (39.4%). There was no difference in the total rate of complication (p = 0.461), minor complications (p = 0.443), major complications (p = 0.777), and minor and major complications (p = 0.762) between the control group and children with behavioral disorders. Behavior was not observed to influence the incidence of OIF or skin/soft tissue reactions after implantation of OBCD in pediatric patients.

  14. Decisional Conflict in Parents Considering Bone-Anchored Hearing Devices in Children With Unilateral Aural Atresia.

    Science.gov (United States)

    Graham, M Elise; Haworth, Rebecca; Chorney, Jill; Bance, Manohar; Hong, Paul

    2015-12-01

    The benefits of bone-anchored hearing devices (BAHD) in children with unilateral aural atresia are controversial. We sought to determine whether there is parental decisional conflict surrounding elective placement of BAHD for this indication. Caregivers of pediatric patients with unilateral aural atresia and normal contralateral ear undergoing percutaneous BAHD consultation were enrolled. All consultations were carried out by one pediatric otolaryngologist in a consistent manner. After consultation, the participants completed a demographics form and the Decisional Conflict Scale (DCS) questionnaire. Twenty-three caregivers of 15 male (65.2%) and 8 female (34.8%) children (mean age 5.65 years) participated. The overall median DCS score was 15.63 (standard error = 4.21). Significant decisional conflict (DCS score ≥ 25) was found in 10 participants (43.5%). The median DCS score in the group choosing surgery was 5.47, and it was 23.44 in those who did not choose surgery (Mann-Whitney U = 39, Z = -1.391, P = .164). The median DCS score for mothers and fathers was 25 and 3.91, respectively. Many parents experienced significant decisional conflict when considering percutaneous BAHD surgery in children with unilateral aural atresia in our study population. Future research should explore the impact of decisional conflict on health outcomes. © The Author(s) 2015.

  15. Bone-anchored hearing device surgery: Linear incision without soft tissue reduction. A prospective study.

    Science.gov (United States)

    Altuna, Xabier; Navarro, Juan José; Palicio, Idoia; Álvarez, Leire

    2015-01-01

    The classic surgical procedure for percutaneous bone-anchored hearing devices involves removal of a large area of subcutaneous tissue down to the periosteum. This leads to alopecia and raises the risk of devascularization of the overlying skin with the potential for infection and scarring. The objective of this study was to determine the results of implant placement using a single, linear incision with no underlying soft tissue reduction. A prospective study was conducted in our hospital over a period of 14 months in all consecutive surgeries performed using this technique in adults. Patients were reviewed regularly (week 1, week 3, weeks 4-6 and months 3, 6 and 12) to assess wound healing including evaluation with the Holgers scale. Corresponding to 34 patients, 34 cases were consecutively enrolled in this study. We found that 15% of the patients had minor skin reactions during the first visit (Holgers grade 1 or 2); this number raised to 20% in week 3, but at week 4 only 1 patient had a reaction score of 1 (which was solved by week 6). None of the cases required revision surgery and all skin reactions were treated topically. Our results suggest that the tissue preservation technique is a simple and effective insertion technique with a favourable healing process and cosmesis. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  16. Digital processing technology for bone-anchored hearing aids: randomised comparison of two devices in hearing aid users with mixed or conductive hearing loss.

    Science.gov (United States)

    Hill-Feltham, P; Roberts, S A; Gladdis, R

    2014-02-01

    This study compared the performance of two new bone-anchored hearing aids with older bone-anchored hearing aids that were not fully digital. Fourteen experienced bone-anchored hearing aid users participated in this cross-over study. Performance of their existing bone-anchored hearing aid was assessed using speech-in-noise testing and questionnaires. Participants were then fitted with either a Ponto Pro or a BP100 device. After four weeks of use with each new device, the same assessments were repeated. Speech-in-noise testing for the 50 per cent signal-to-noise ratio (the ratio at which 50 per cent of responses were correct) showed no significant differences between the Ponto Pro and the BP100 devices (p = 0.1) However, both devices showed significant improvement compared with the participants' previous bone-anchored hearing aid devices (p bone-anchored hearing aids demonstrated superior speech processing compared with the previous generation of devices. There were no substantial differences between the two digital devices in either objective or subjective tests.

  17. Investigation of a novel completely-in-the-canal direct-drive hearing device: a temporal bone study.

    Science.gov (United States)

    Mahboubi, Hossein; Paulick, Peyton; Kiumehr, Saman; Merlo, Mark; Bachman, Mark; Djalilian, Hamid Reza

    2013-01-01

    Whether a prototype direct-drive hearing device (DHD) is effective in driving the tympanic membrane (TM) in a temporal bone specimen to enable it to potentially treat moderate-to-severe hearing loss. Patient satisfaction with air conduction hearing aids has been low because of sound distortion, occlusion effect, and feedback issues. Implantable hearing aids provide a higher quality sound but require surgery for placement. The DHD was designed to combine the ability of driving the ossicular chain with placement in the external auditory canal. DHD is a 3.5-mm wide device that could fit entirely into the bony ear canal and directly drive the TM rather than use a speaker. A cadaveric temporal bone was prepared. The device developed in our laboratory was coupled to the external surface of the TM and against the malleus. Frequency sweeps between 300 Hz to 12 kHz were performed in 2 different coupling methods at 104 and 120 dB, and the DHD was driven with various levels of current. Displacements of the posterior crus of the stapes were measured using a laser Doppler vibrometer. The DHD showed a linear frequency response from 300 Hz to 12 kHz. Placement against the malleus showed higher amplitudes and lower power requirements than when the device was placed on the TM. DHD is a small completely-in-the-canal device that mechanically drives the TM. This novel device has a frequency output wider than most air conduction devices. Findings of the current study demonstrated that the DHD had the potential of being incorporated into a hearing aid in the future.

  18. 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

  19. An experimental and computational investigation of the post-yield behaviour of trabecular bone during vertebral device subsidence.

    Science.gov (United States)

    Kelly, Nicola; Harrison, Noel M; McDonnell, Pat; McGarry, J Patrick

    2013-08-01

    Interbody fusion device subsidence has been reported clinically. An enhanced understanding of the mechanical behaviour of the surrounding bone would allow for accurate predictions of vertebral subsidence. The multiaxial inelastic behaviour of trabecular bone is investigated at a microscale and macroscale level. The post-yield behaviour of trabecular bone under hydrostatic and confined compression is investigated using microcomputed tomography-derived microstructural models, elucidating a mechanism of pressure-dependent yielding at the macroscopic level. Specifically, microstructural trabecular simulations predict a distinctive yield point in the apparent stress-strain curve under uniaxial, confined and hydrostatic compression. Such distinctive apparent stress-strain behaviour results from localised stress concentrations and material yielding in the trabecular microstructure. This phenomenon is shown to be independent of the plasticity formulation employed at a trabecular level. The distinctive response can be accurately captured by a continuum model using a crushable foam plasticity formulation in which pressure-dependent yielding occurs. Vertebral device subsidence experiments are also performed, providing measurements of the trabecular plastic zone. It is demonstrated that a pressure-dependent plasticity formulation must be used for continuum level macroscale models of trabecular bone in order to replicate the experimental observations, further supporting the microscale investigations. Using a crushable foam plasticity formulation in the simulation of vertebral subsidence, it is shown that the predicted subsidence force and plastic zone size correspond closely with the experimental measurements. In contrast, the use of von Mises, Drucker-Prager and Hill plasticity formulations for continuum trabecular bone models lead to over prediction of the subsidence force and plastic zone.

  20. 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.

  1. Powered bone marrow biopsy procedures produce larger core specimens, with less pain, in less time than with standard manual devices

    Directory of Open Access Journals (Sweden)

    Larry J. Miller

    2011-07-01

    Full Text Available Bone marrow sampling remains essential in the evaluation of hematopoietic and many non-hematopoietic disorders. One common limitation to these procedures is the discomfort experienced by patients. To address whether a Powered biopsy system could reduce discomfort while providing equivalent or better results, we performed a randomized trial in adult volunteers. Twenty-six subjects underwent bilateral biopsies with each device. Core samples were obtained in 66.7% of Manual insertions; 100% of Powered insertions (P=0.002. Initial mean biopsy core lengths were 11.1±4.5 mm for the Manual device; 17.0±6.8 mm for the Powered device (P<0.005. Pathology assessment for the Manual device showed a mean length of 6.1±5.6 mm, width of 1.0±0.7 mm, and volume of 11.0±10.8 mm3. Powered device measurements were mean length of 15.3±6.1 mm, width of 2.0±0.3 mm, and volume of 49.1±21.5 mm3 (P<0.001. The mean time to core ejection was 86 seconds for Manual device; 47 seconds for the Powered device (P<0.001. The mean second look overall pain score was 33.3 for the Manual device; 20.9 for the Powered (P=0.039. We conclude that the Powered biopsy device produces superior sized specimens, with less overall pain, in less time.

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

    Science.gov (United States)

    2010-01-01

    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. PMID:20482845

  3. Extracortical plate fixation with new plate inserts and cerclage wires for the treatment of periprosthetic hip fractures.

    Science.gov (United States)

    Bastian, Johannes D; Butscher, Andre; Bigolin, Gianni; Zumstein, Matthias A; Nötzli, Hubert P

    2014-03-01

    Fixation of periprosthetic hip fractures with intracortical anchorage might not be feasible in cases with bulky implants and/or poor bone stock. Rotational stability of new plate inserts with extracortical anchorage for cerclage fixation was measured and compared to the stability found using a standard technique in a biomechanical setup using a torsion testing machine. In a synthetic PUR bone model, transverse fractures were fixed distally using screws and proximally by wire cerclages attached to the plates using "new" (extracortical anchorage) or "standard" (intracortical anchorage) plate inserts. Time to fracture consolidation and complications were assessed in a consecutive series of 18 patients (18 female; mean age 81 years, range 55-92) with periprosthetic hip fractures (ten type B1, eight type C-Vancouver) treated with the new device between July 2003 and July 2010. The "new" device showed a higher rotational stability than the "standard" technique (p Fractures showed radiographic consolidation after 14 ± 5 weeks (mean ± SD) postoperatively in patients. Revision surgery was necessary in four patients, unrelated to the new technique. In periprosthetic hip fractures in which fixation with intracortical anchorage using conventional means might be difficult due to bulky revision stems and/or poor bone stock, the new device may be an addition to the range of existing implants.

  4. A multicenter study on objective and subjective benefits with a transcutaneous bone-anchored hearing aid device: first Nordic results.

    Science.gov (United States)

    Hougaard, Dan Dupont; Boldsen, Soren Kjaergaard; Jensen, Anne Marie; Hansen, Soren; Thomassen, Per Cayé

    2017-08-01

    Examination of objective as well as subjective outcomes with a new transcutaneous bone-anchored hearing aid device. The study was designed as a prospective multicenter consecutive case-series study involving tertiary referral centers at two Danish University Hospitals. A total of 23 patients were implanted. Three were lost to follow-up. Patients had single-sided deafness, conductive or mixed hearing loss. Rehabilitative. Aided and unaided sound field hearing was evaluated objectively using (1) pure warble tone thresholds, (2) pure-tone average (PTA4), (3) speech discrimination score (SDS) in quiet, and (4) speech reception threshold 50% at 70 dB SPL noise level (SRT50%). Subjective benefit was evaluated by three validated questionnaires: (1) the IOI-HA, (2) the SSQ-12, and (3) a questionnaire evaluating both the frequency and the duration of hearing aid usage. The mean aided PTA4 was lowered by 14.7 dB. SDS was increased by 37.5% at 50 dB SPL, SRT50% in noise improved 1.4 dB. Aided thresholds improved insignificantly at frequencies above 2 kHz. 52.9% of the patients used their device every day, and 76.5% used the device at least 5 days a week. Mean IOI-HA score was 3.4, corresponding to a good benefit. In SSQ-12, "quality of hearing" scored especially high. Patients with a conductive and/or mixed hearing loss benefitted the most. This device demonstrates a significant subjective hearing benefit 8 month post surgery. In patients with conductive and/or mixed hearing losses, patient satisfaction and frequency of use were high. Objective gain measures showed less promising results especially in patients with single-sided deafness (SSD) compared to other bone conduction devices.

  5. 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.

  6. In vitro simulation of pathological bone conditions to predict clinical outcome of bone tissue engineered materials

    Science.gov (United States)

    Nguyen, Duong Thuy Thi

    According to the Centers for Disease Control, the geriatric population of ≥65 years of age will increase to 51.5 million in 2020; 40% of white women and 13% of white men will be at risk for fragility fractures or fractures sustained under normal stress and loading conditions due to bone disease, leading to hospitalization and surgical treatment. Fracture management strategies can be divided into pharmaceutical therapy, surgical intervention, and tissue regeneration for fracture prevention, fracture stabilization, and fracture site regeneration, respectively. However, these strategies fail to accommodate the pathological nature of fragility fractures, leading to unwanted side effects, implant failures, and non-unions. Compromised innate bone healing reactions of patients with bone diseases are exacerbated with protective bone therapy. Once these patients sustain a fracture, bone healing is a challenge, especially when fracture stabilization is unsuccessful. Traditional stabilizing screw and plate systems were designed with emphasis on bone mechanics rather than biology. Bone grafts are often used with fixation devices to provide skeletal continuity at the fracture gap. Current bone grafts include autologous bone tissue and donor bone tissue; however, the quality and quantity demanded by fragility fractures sustained by high-risk geriatric patients and patients with bone diseases are not met. Consequently, bone tissue engineering strategies are advancing towards functionalized bone substitutes to provide fracture reconstruction while effectively mediating bone healing in normal and diseased fracture environments. In order to target fragility fractures, fracture management strategies should be tailored to allow bone regeneration and fracture stabilization with bioactive bone substitutes designed for the pathological environment. The clinical outcome of these materials must be predictable within various disease environments. Initial development of a targeted

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

    International Nuclear Information System (INIS)

    Dallap, B.L.; Bramlage, L.R.; Embertson, R.M.

    1999-01-01

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

  8. Horizontal alveolar ridge augmentation using autologous press fit bone cylinders and micro-lag-screw fixation: technical note and initial experience.

    Science.gov (United States)

    Streckbein, Philipp; Kähling, Christopher; Wilbrand, Jan-Falco; Malik, Christoph-Yves; Schaaf, Heidrun; Howaldt, Hans-Peter; Streckbein, Roland

    2014-07-01

    The use of autologous block bone grafts for horizontal alveolar ridge augmentation in dental implantology is a common surgical procedure. Typically, bone grafts are individually moulded. The aim of this paper is to introduce an innovative procedure in lateral bone augmentation, where the recipient side is adjusted to the graft, not vice versa as in common procedures. Our initial clinical experience of twenty-five consecutive cases is presented. Adjusted trephine drills were used to harvest partly cylindrical grafts from the retromolar region of the mandible. After preparing the recipient site with accurately fitting grinding drills, the bone grafts were transplanted. The horizontally compromised alveolar ridges were successfully augmented and treated with dental implants. No major complication occurred during transplantation, the healing period, and subsequent implant therapy in our experimental setting with 25 patients and 38 augmentation procedures. One out of twenty-five patients presented with temporary dysaesthesia of the inferior alveolar nerve. The new method presented is an effective treatment option for horizontal alveolar ridge augmentation prior to single implant installation. Further studies should evaluate the donor site morbidity and long-term outcome on a larger population. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Novel Osteogenic Ti-6Al-4V Device For Restoration Of Dental Function In Patients With Large Bone Deficiencies: Design, Development And Implementation

    Science.gov (United States)

    Cohen, D. J.; Cheng, A.; Kahn, A.; Aviram, M.; Whitehead, A. J.; Hyzy, S. L.; Clohessy, R. M.; Boyan, B. D.; Schwartz, Z.

    2016-01-01

    Custom devices supporting bone regeneration and implant placement are needed for edentulous patients with large mandibular deficiencies where endosteal implantation is not possible. We developed a novel subperiosteal titanium-aluminum-vanadium bone onlay device produced by additive manufacturing (AM) and post-fabrication osteogenic micro-/nano-scale surface texture modification. Human osteoblasts produced osteogenic and angiogenic factors when grown on laser-sintered nano-/micro-textured surfaces compared to smooth surfaces. Surface-processed constructs caused higher bone-to-implant contact, vertical bone growth into disk pores (microCT and histomorphometry), and mechanical pull-out force at 5 and 10 w on rat calvaria compared to non surface-modified constructs, even when pre-treating the bone to stimulate osteogenesis. Surface-modified wrap-implants placed around rabbit tibias osseointegrated by 6 w. Finally, patient-specific constructs designed to support dental implants produced via AM and surface-processing were implanted on edentulous mandibular bone. 3 and 8 month post-operative images showed new bone formation and osseointegration of the device and indicated stability of the dental implants. PMID:26854193

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

    International Nuclear Information System (INIS)

    Lee, Sung Youl; Kim, Jae Ryang; Kim, Eun Rim; Lee, Jun Ho; Lee, Chang Hyung; Park, Chang Won

    2016-01-01

    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

  11. 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.

  12. 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.

  13. Quality-of-life outcomes after bone-anchored hearing device surgery in children with single-sided sensorineural deafness.

    Science.gov (United States)

    Doshi, Jayesh; Banga, Rupan; Child, Anne; Lawrence, Rebecca; Reid, Andrew; Proops, David; McDermott, Ann-Louise

    2013-01-01

    To report our experience in a series of children with single-sided sensorineural deafness where a bone-anchored hearing device (BAHD) was used for auditory rehabilitation. Retrospective case review. Tertiary referral centre. Eight children (4 boys and 4 girls) who had BAHD surgery for single-sided sensorineural deafness between 2007 and 2010. Bone-anchored hearing device was used for auditory rehabilitation. Glasgow Children's Benefit Inventory (GCBI), Single-sided Deafness (SSD) Questionnaire and change in health benefit scores (visual analogue scale). All but one of the children showed a positive GCBI score; the child that reported a negative score was because of low self confidence and self-esteem issues secondary to bullying at school. The results of the SSD questionnaire were generally positive with a mean satisfaction score of the BAHD as 9/10. All the children had an improvement in heath benefit. Our findings add further evidence to support patient perceived benefit of a BAHD in single sided sensorineural deafness in the paediatric population.

  14. A novel modular device for 3-D bone cell culture and non-destructive cell analysis.

    Science.gov (United States)

    Kunz, Friederike; Bergemann, Claudia; Klinkenberg, Ernst-Dieter; Weidmann, Arne; Lange, Regina; Beck, Ulrich; Nebe, J Barbara

    2010-09-01

    Synthetic materials have emerged as bone substitutes for filling bone defects of critical sizes. Because bone healing requires a mechanically resistant matrix (scaffold) attractive to osteogenic cells and must allow revascularization for nutrient and oxygen supply, scaffold-based strategies focus on the further development of chemical and physical qualities of the material. Cellular ingrowth towards the scaffold center is critical; therefore selective information from inner regions, in particular from the central part, is essential. In this paper we introduce a novel modular in vitro system for three-dimensional (3-D) in vitro bone cell cultures. This 3-D system is developed exclusively for in vitro research purposes, with special emphasis on the geometrical scaffold design (pore size, pore design). The system is composed of a stack of titanium slices which are mounted on a clamp and which enable the separate monitoring of cell growth patterns on every single slice of the slide stack. In this way we are able to gain selective information about the regulation of the cell physiology in the inner part of the 3-D construct which can be used for the development of an optimized scaffold design for orthopedic implants. 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. 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

  16. The effect of the association of near infrared laser therapy, bone morphogenetic proteins, and guided bone regeneration on tibial fractures treated with internal rigid fixation: a Raman spectroscopic study.

    Science.gov (United States)

    Lopes, Cibele B; Pacheco, Marcos T T; Silveira, Landulfo; Cangussú, Maria Cristina T; Pinheiro, Antonio L B

    2010-09-15

    Fractures have different etiology and treatment and may be associated or not to bone losses. Laser light has been shown to improve bone healing. We aimed to assess, through Raman spectroscopy, the level of CHA (approximately 958 cm(-1)) on complete fractures animals treated with IRF treated or not with Low Level Laser Therapy-LLLT and associated or not to BMPs and GBR. Complete tibial fractures were created on 15 animals that were divided into five groups. LLLT (Laser Unit, Kondortech, São Carlos, SP, Brazil, lambda790 nm, 4 J/cm(2)/point, 40 mW, phi approximately 0.5 cm(2), 16 J/cm(2) session) started immediately after surgery and repeated at 48 h interval (2 weeks). Animal death occurred after 30 days. Raman spectroscopy was performed at the surface of the fracture. Our results showed significant differences between the groups IRF + BL /IRF_NBL (p = 0.05); between all experimental groups and untreated bone; bone/IRF + BL; IRF + BL + Bio + GBR; IRF + BL + LLLT; IRF + BL + Bio + GBR + LLLT; IRF_NBL (p bone healing on fractured bones due to increased levels of CHA. (c) 2010 Wiley Periodicals, Inc.

  17. Preliminary functional results and quality of life after implantation of a new bone conduction hearing device in patients with conductive and mixed hearing loss.

    Science.gov (United States)

    Ihler, Friedrich; Volbers, Laura; Blum, Jenny; Matthias, Christoph; Canis, Martin

    2014-02-01

    To review functional results and quality of life of the first patients implanted with a newly introduced bone conduction implant system. Retrospective chart analysis of 6 patients (6 ears) implanted for conductive hearing loss (CHL) and mixed hearing loss (MHL) in 1 tertiary referral center between July 2012 and February 2013. Implantation of a new bone conduction hearing device. Pure tone audiometry (air conduction and bone conduction thresholds, pure tone average, air-bone gap, and functional gain), speech audiometry (Freiburg Monosyllabic Test), intraoperative and postoperative complication rate, and patient satisfaction (Glasgow benefit inventory [GBI]) were assessed. Air-conduction pure tone average (PTA) was 58.8 ± 8.2 dB HL. Unaided average air-bone gap (ABG) was 33.3 ± 6.2 dB. Aided air-conduction PTA in sound field was 25.2 ± 5.1 dB HL. Aided average ABG was -0.3 ± 7.3 dB. Average functional gain was 33.6 ± 7.2 dB. Mean improvement of GBI was +36.1. No intraoperative complications occurred. During a follow-up period of 8.5 ± 2.2 months, no device failure and no need for revision surgery occurred. Audiometric results of the new bone conduction hearing system are satisfying and comparable to the results of devices that have been applied previously for CHL and MHL. Intraoperatively and postoperatively, no complications were noted.

  18. Intrascleral IOL Fixation.

    Science.gov (United States)

    Jacob, Soosan

    2017-01-01

    Intrascleral sutureless intraocular lens (IOL) fixation utilizes direct haptic fixation within the sclera in eyes with deficient capsular support. This has advantages of long-term stability, good control of tilt and decentration, and lesser pseudophakodonesis. This review summarizes various techniques for intrascleral haptic fixation, results, complications, adaptations in special situations, modifications of the technique, combination surgeries, and intrascleral capsular bag fixation techniques (glued capsular hook). Copyright 2017 Asia-Pacific Academy of Ophthalmology.

  19. A novel technique for impaction bone grafting in acetabular reconstruction of revision total hip arthroplasty using an ex vivo compaction device

    International Nuclear Information System (INIS)

    Akiyama, Haruhiko; Takemoto, Mitsuru; Morishima, Takkan

    2011-01-01

    Impaction bone grafting allows restoration of the acetabular bone stock in revision hip arthroplasty. The success of this technique depends largely on achieving adequate initial stability of the component. To obtain well-compacted, well-graded allograft aggregates, we developed an ex vivo compaction device to apply it in revision total hip arthroplasty on the acetabular side, and characterized mechanical properties and putative osteoconductivity of allograft aggregates. Morselized allograft bone chips were compacted ex vivo using the creep technique and subsequent impaction technique to form the bone aggregates. Impaction allograft reconstruction of the acetabulum using an ex vivo compaction device was performed on eight hips. The mechanical properties and three-dimensional micro-CT-based structural characteristics of the bone aggregates were investigated. In clinical practice, this technique offered good reproducibility in reconstructing the cavity and the segmental defects of the acetabulum, with no migration and no loosening of the component. In vitro analysis showed that the aggregates generated from 25 g fresh-frozen bone chips gained compression stiffness of 13.5-15.4 MPa under uniaxial consolidation strain. The recoil of the aggregates after compaction was 2.6-3.9%. The compression stiffness and the recoil did not differ significantly from those measured using a variety of proportions of large- and small-sized bone chips. Micro-CT-based structural analysis revealed average pore sizes of 268-299 μm and average throat diameter of pores in the bone aggregates of more than 100 μm. These sizes are desirable for osteoconduction, although large interconnected pores of more than 500 μm were detectable in association with the proportion of large-sized bone chips. Cement penetration into the aggregates was related to the proportion of large-sized bone chips. This study introduces the value of an ex vivo compaction device in bone graft compaction in clinical

  20. Comparison of implant stability measurement devices for bone-anchored hearing aid systems.

    Science.gov (United States)

    Westover, Lindsey; Faulkner, Gary; Hodgetts, William; Raboud, Don

    2018-01-01

    The success of implants for bone-anchored hearing aids (BAHA) relies on proper osseointegration at the bone-implant interface. Clinical evaluation of implant stability is important in prescribing loading, identifying the risk of failure, and monitoring the long-term health of the implant. The purpose of this in vitro study was to evaluate 2 measurement systems for BAHA implant stability: the most commonly used, Osstell implant stability quotient (ISQ), and a newly developed advance system for implant stability testing (ASIST). BAHA implants (Oticon Medical Ponto and Cochlear BAHA Connect systems) were installed in plastic materials with adhesive to simulate implants integrated in bone with varying levels of interface stiffness. Different lengths of BAHA abutments were used with each implant specimen, and stability measurements were obtained with both the Osstell ISQ and the ASIST systems. The measurement systems were evaluated in terms of sensitivity to differences in interface stiffness and the effect of abutment length on the stability measurement. Repeated measures ANOVA followed by post hoc t tests were used for the comparisons with a Bonferroni adjusted alpha value of .05/15 = .003 to control for potential type 1 errors. Changing the abutment length of a single implant installation had minimal effect on the ASIST stability coefficient, whereas large variations were observed in the Osstell implant stability quotient (ISQ). The Osstell showed a clear relationship of decreasing ISQ with increasing abutment length for both the Oticon Medical and the Cochlear implant systems. Both the ASIST and the Osstell were found to be sensitive to changes in interface properties, with the ASIST being more sensitive to these changes. The ASIST system is more sensitive to changes in interface properties and shows smaller variation because of changes in abutment length than the Osstell ISQ system. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry

  1. 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

    . This paper describes how this was solved using the active shape model (ASM). Standard ASM is unable to locate the metacarpal shafts in the direction along the bones. Therefore ASM was extended with a translation operator, which solved the problem. A hierarchical filtering method was used to construct......-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....

  2. Four quadrant parallel peripheral screw fixation for displaced femoral neck fractures in elderly patients

    Directory of Open Access Journals (Sweden)

    Bhava RJ Satish

    2013-01-01

    Conclusion: Closed reduction and cannulated cancellous screw fixation gives satisfactory functional results in large group of elderly patients. The four quadrant parallel peripheral (FQPP screw fixation technique gives good stability, allows controlled collapse, avoids fixation failure and achieves predictable bone healing in displaced femoral neck fracture in patients ≥50 years of age.

  3. Premaxillary osteotomy fixation in bilateral cleft lip/palate: Introducing a new technique

    Directory of Open Access Journals (Sweden)

    Amin Rahpeyma

    2016-04-01

    Conclusion: In protruding premaxilla, osteotomy and fixation of premaxilla with miniplate to the vomer bone during alveolar bone grafting through a lip-split approach yielded satisfactory results in patients requiring secondary functional cheilorhinoplasty.

  4. Amplification of transcutaneous and percutaneous bone-conduction devices with a test-band in an induced model of conductive hearing loss.

    Science.gov (United States)

    Park, Marn Joon; Lee, Jae Ryung; Yang, Chan Joo; Yoo, Myung Hoon; Jin, In Suk; Choi, Chi Ho; Park, Hong Ju

    2016-11-01

    Transcutaneous devices have a disadvantage, the dampening effect by soft tissue between the bone and devices. We investigated hearing outcomes with percutaneous and transcutaneous devices using test-bands in an induced unilateral conductive hearing loss. Comparison of hearing outcomes of two devices in the same individuals. The right ear was plugged in 30 subjects and a test-band with devices (Cochlear™ Baha® BP110 Power and Sophono® Alpha-2 MPO™) was applied on the right mastoid tip with the left ear masked. Sound-field thresholds, speech recognition thresholds (SRTs), and word recognition scores (WRSs) were compared. Aided thresholds of Sophono were significantly better than those of Baha at most frequencies. Sophono WRSs (86 ± 12%) at 40 dB SPL and SRTs (14 ± 5 dB HL) were significantly better than those (73 ± 24% and 23 ± 8 dB HL) of Baha. However, Sophono WRSs (98 ± 3%) at 60 dB SPL did not differ from Baha WRSs (95 ± 12%). Amplifications of the current transcutaneous device were not inferior to those of percutaneous devices with a test-band in subjects with normal bone-conduction thresholds. Since the percutaneous devices can increase the gain when fixed to the skull by eliminating the dampening effect, both devices are expected to provide sufficient hearing amplification.

  5. A multicenter study on objective and subjective benefits with a transcutaneous bone-anchored hearing aid device

    DEFF Research Database (Denmark)

    Hougaard, Dan Dupont; Boldsen, Soren Kjaergaard; Jensen, Anne Marie

    2017-01-01

    Examination of objective as well as subjective outcomes with a new transcutaneous bone-anchored hearing aid device. The study was designed as a prospective multicenter consecutive case-series study involving tertiary referral centers at two Danish University Hospitals. A total of 23 patients were...... implanted. Three were lost to follow-up. Patients had single-sided deafness, conductive or mixed hearing loss. Intervention: Rehabilitative. Aided and unaided sound field hearing was evaluated objectively using (1) pure warble tone thresholds, (2) pure-tone average (PTA4), (3) speech discrimination score...... (SDS) in quiet, and (4) speech reception threshold 50% at 70 dB SPL noise level (SRT50%). Subjective benefit was evaluated by three validated questionnaires: (1) the IOI-HA, (2) the SSQ-12, and (3) a questionnaire evaluating both the frequency and the duration of hearing aid usage. The mean aided PTA4...

  6. 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.

  7. History of internal fixation with plates (part 2): new developments after World War II; compressing plates and locked plates.

    Science.gov (United States)

    Hernigou, Philippe; Pariat, Jacques

    2017-07-01

    The first techniques of operative fracture with plates were developed in the 19th century. In fact, at the beginning these methods consisted of an open reduction of the fracture usually followed by a very unstable fixation. As a consequence, the fracture had to be opened with a real risk of (sometimes lethal) infection, and due to unstable fixation, protection with a cast was often necessary. During the period between World Wars I and II, plates for fracture fixation developed with great variety. It became increasingly recognised that, because a fracture of a long bone normally heals with minimal resorption at the bone ends, this may result in slight shortening and collapse, so a very rigid plate might prevent such collapse. However, as a consequence, delayed healing was observed unless the patient was lucky enough to have the plate break. One way of dealing with this was to use a slotted plate in which the screws could move axially, but the really important advance was recognition of the role of compression. After the first description of compression by Danis with a "coapteur", Bagby and Müller with the AO improved the technique of compression. The classic dynamic compression plates from the 1970s were the key to a very rigid fixation, leading to primary bone healing. Nevertheless, the use of strong plates resulted in delayed union and the osteoporosis, cancellous bone, comminution, and/or pathological bone resulted in some failures due to insufficient stability. Finally, new devices represented by locking plates increased the stability, contributing to the principles of a more biological osteosynthesis while giving enough stability to allow immediate full weight bearing in some patients.

  8. Use of a centrifugation-based, point-of-care device for production of canine autologous bone marrow and platelet concentrates.

    Science.gov (United States)

    Thoesen, Michael S; Berg-Foels, Wendy S Vanden; Stokol, Tracy; Rassnick, Kenneth M; Jacobson, May S; Kevy, Sherwin V; Todhunter, Rory J

    2006-10-01

    To analyze a centrifugation-based, point-of-care device that concentrates canine platelets and bone marrow-derived cells. 19 adult sexually intact dogs. Anticoagulated peripheral blood (60 mL) and 60 mL of anticoagulated bone marrow aspirate (BMA) were concentrated by centrifugation with the centrifugation-based, point-of-care device to form a platelet and a bone marrow concentrate (BMC) from 11 dogs. Blood samples were analyzed on the basis of hemograms, platelet count, and PCV. The BMA and BMC were analyzed to determine PCV, total nucleated cell count, RBC count, and differential cell counts. The BMC stromal cells were cultured in an osteoinductive medium. Eight additional dogs were used to compare the BMC yield with that in which heparin was infused into the bone marrow before aspiration. The centrifugation-based, point-of-care device concentrated platelets by 6-fold over baseline (median recovery, 63.1%) with a median of 1,336 x 10(3) platelets/microL in the 7-mL concentrate. The nucleated cells in BMCs increased 7-fold (median recovery, 42.9%) with a median of 720 x 10(3) cells/microL in the 4-mL concentrate. The myeloid nucleated cells and mononuclear cells increased significantly in BMCs with a significant decrease in PCV, compared with that of BMAs. Stromal cell cultures expressed an osteoblastic phenotype in culture. Infusion of heparin into the bone marrow eliminated clot formation and created less variation in the yield (median recovery, 61.9%). Bone marrow-derived cell and platelet-rich concentrates may form bone if delivered in an engineered graft, thus decreasing the need for cancellous bone grafts.

  9. 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 screw may be used safely in the majority of patients with fifth metatarsal fractures.

  10. Development of thermo-mechanical processing for fabricating highly durable β-type Ti-Nb-Ta-Zr rod for use in spinal fixation devices.

    Science.gov (United States)

    Narita, Kengo; Niinomi, Mitsuo; Nakai, Masaaki; Hieda, Junko; Oribe, Kazuya

    2012-05-01

    The mechanical strength of a beta titanium alloy such as Ti-Nb-Ta-Zr alloy (TNTZ) can be improved significantly by thermo-mechanical treatment. In this study, TNTZ was subjected to solution treatment, cold caliber rolling, and cold swaging before aging treatment to form a rod for spinal fixation. The {110}(β) are aligned parallel to the cross-section with two strong peaks approximately 180° apart, facing one another, in the TNTZ rods subjected to cold caliber rolling and six strong peaks at approximately 60° intervals, facing one another, in the TNTZ rods subjected to cold swaging. Therefore, the TNTZ rods subjected to cold swaging have a more uniform structure than those subjected to cold caliber rolling. The orientation relationship between the α and β phases is different. A [110](β)//[121](α), (112)(β)//(210)(α) orientation relationship is observed in the TNTZ rods subjected to aging treatment at 723 K after solution treatment and cold caliber rolling. On the other hand, a [110](β)//[001](α), (112)(β)//(200)(α) orientation relationship is observed in TNTZ rod subjected to aging treatment at 723 K after cold swaging. A high 0.2% proof stress of about 1200 MPa, high elongation of 18%, and high fatigue strength of 950 MPa indicate that aging treatment at 723 K after cold swaging is the optimal thermo-mechanical process for a TNTZ rod. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. 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

  12. Intramedullary Nail Fixation of Atypical Femur Fractures With Bone Marrow Aspirate Concentrate Leads to Faster Union: A Case-Control Study.

    Science.gov (United States)

    Lovy, Andrew J; Kim, Jun S; Di Capua, John; Somani, Sulaiman; Shim, Stephanie; Keswani, Aakash; Hasija, Rohit; Wu, Yangguan; Joseph, David; Ghillani, Richard

    2017-07-01

    To evaluate bone marrow aspirate concentrate (BMAC) use in the treatment of AFF. Retrospective case control. Level 1 trauma center. Complete AFF, defined according to American Society of Bone and Mineral Research (ASBMR) criteria, from September 2009 to April 2015 with minimum 1-year follow-up. Operative treatment with antegrade intramedullary nails. Beginning June 2014, BMAC from the ipsilateral iliac crest was added to all AFFs. Time to union as determined by a blinded panel of 3 attending orthopaedic surgeons, union rates, complications. Thirty-five patients with 36 AFFs were reviewed, of which 33 AFFs were included and 11 received BMAC. Alendronate was the most commonly prescribed bisphosphonate, with a similar mean duration of use in controls and BMAC cases (5.6 versus 6 years, P = 0.79). BMAC use significantly decreased time to union (3.5 versus 6.8 months, P = 0.004). Varus malreduction was associated with a significant delay in union (9.7 versus 4.7 months, P = 0.04). Overall, 1 year union rate was 86.2% and nonsignificantly higher in BMAC compared with controls (100.0% versus 77.3%, P = 0.11). Multivariate analysis revealed BMAC and varus malreduction as independent predictors of time to union. There were no complications related to BMAC use. Our findings support intramedullary nailing of AFFs as an effective treatment option with a low surgical complication rate and highlight the importance of avoiding varus malreduction. BMAC use significantly reduced time to fracture union without an increase in surgical complication rates. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

  13. 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.

  14. Percutaneous Image-Guided Screw Fixation of Bone Lesions in Cancer Patients: Double-Centre Analysis of Outcomes including Local Evolution of the Treated Focus

    Energy Technology Data Exchange (ETDEWEB)

    Cazzato, Roberto Luigi, E-mail: gigicazzato@hotmail.it; Koch, Guillaume, E-mail: guillaume.koch@chru-strasbourg.fr [Hôpitaux Universitaires de Strasbourg, HUS, Department of Interventional Radiology, Nouvel Hôpital Civil (France); Buy, Xavier, E-mail: x.buy@bordeaux.unicancer.fr [Institut Bergonié, Department of Radiology (France); Ramamurthy, Nitin, E-mail: nitin-ramamurthy@hotmail.com [Norfolk and Norwich University Hospital, Department of Radiology (United Kingdom); Tsoumakidou, Georgia, E-mail: georgia.tsoumakidou@chru-strasbourg.fr; Caudrelier, Jean, E-mail: jean.caudrelier@chru-strasbourg.fr [Hôpitaux Universitaires de Strasbourg, HUS, Department of Interventional Radiology, Nouvel Hôpital Civil (France); Catena, Vittorio, E-mail: v.catena@bordeaux.unicancer.fr [Institut Bergonié, Department of Radiology (France); Garnon, Julien, E-mail: juleiengarnon@gmail.com [Hôpitaux Universitaires de Strasbourg, HUS, Department of Interventional Radiology, Nouvel Hôpital Civil (France); Palussiere, Jean, E-mail: j.palussiere@bordeaux.unicancer.fr [Institut Bergonié, Department of Radiology (France); Gangi, Afshin, E-mail: gangi@unistra.fr [Hôpitaux Universitaires de Strasbourg, HUS, Department of Interventional Radiology, Nouvel Hôpital Civil (France)

    2016-10-15

    AimTo review outcomes and local evolution of treated lesions following percutaneous image-guided screw fixation (PIGSF) of pathological/insufficiency fractures (PF/InF) and impeding fractures (ImF) in cancer patients at two tertiary centres.Materials and methodsThirty-two consecutive patients (mean age 67.5 years; range 33–86 years) with a range of tumours and prognoses underwent PIGSF for non/minimally displaced PF/InF and ImF. Screws were placed under CT/fluoroscopy or cone-beam CT guidance, with or without cementoplasty. Clinical outcomes were assessed using a simple 4-point scale (1 = worse; 2 = stable; 3 = improved; 4 = significantly improved). Local evolution was reviewed on most recent follow-up imaging. Technical success, complications, and overall survival were evaluated.ResultsThirty-six lesions were treated with 74 screws mainly in the pelvis and femoral neck (58.2 %); including 47.2 % PF, 13.9 % InF, and 38.9 % ImF. Cementoplasty was performed in 63.9 % of the cases. Technical success was 91.6 %. Hospital stay was ≤3 days; 87.1 % of lesions were improved at 1-month follow-up; three major complications (early screw-impingement radiculopathy; accelerated coxarthrosis; late coxofemoral septic arthritis) and one minor complication were observed. Unfavourable local evolution at imaging occurred in 3/24 lesions (12.5 %) at mean 8.7-month follow-up, including poor consolidation (one case) and screw loosening (two cases, at least 1 symptomatic). There were no cases of secondary fractures.ConclusionsPIGSF is feasible for a wide range of oncologic patients, offering good short-term efficacy, acceptable complication rates, and rapid recovery. Unfavourable local evolution at imaging may be relatively frequent, and requires close clinico-radiological surveillance.

  15. Stability Testing of a Wide Bone-Anchored Device after Surgery without Skin Thinning

    Directory of Open Access Journals (Sweden)

    Malou Hultcrantz

    2015-01-01

    Full Text Available Objective. To longitudinally follow the osseointegration using Resonance Frequency Analysis (RFA for different lengths of abutment on a new wide bone-anchored implant, introduced with the non-skin thinning surgical technique. Study Design. A single-center, prospective 1 year study following adults with bone-anchored hearing implants. Materials and Methods. Implantation was performed and followed for a minimum of 1 year. All patients were operated on according to the tissue preserving technique. A 4.5 mm wide fixture (Oticon Medical with varying abutments (9 to 12 mm was used and RFA was tested 1 week, 7 weeks, 6 months, and 12 months later. Implant Stability Quotient (ISQ, was measured from 1 to 100. Stability was compared to a group of patients (N=7 implanted with another brand (Cochlear BI400 of 4.5 mm fixtures. Results. All 10 adults concluded the study. None of the participants lost their implant during the test period indicating a good anchoring of abutments to the wide fixture tested. Stability testing was shown to vary depending on abutment length and time after surgery and with higher values for shorter abutments and increasing values over the first period of time. One patient changed the abutment from 12 to 9 mm and another from a 9 to a 12 during the year. No severe skin problems, numbness around the implant, or cosmetic problems arose. Conclusion. After 1 year of follow-up, combination of a wide fixture implant and the non-skin thinning surgical technique indicates a safe procedure with good stability and no abutment losses.

  16. Optimisation of a Cymbal Transducer for Its Use in a High-power Ultrasonic Cutting Device for Bone Surgery

    Science.gov (United States)

    Bejarano, Fernando; Feeney, Andrew; Lucas, Margaret

    The class V cymbal is a flextensional transducer commonly used in low-power ultrasonic applications. The resonance frequency of the transducer can be tailored by the choice of end-cap and driver materials, and the dimensions of the end-caps. The cymbal transducer has one significant limitation which restricts the operational vibration amplitude of the device. This is the limit imposed by the mechanical strength of the bonding agent between the metal end-cap and the piezoceramic driver. Therefore, when there is an increase in the input power or displacement, the stresses in the bonding layer can lead to debonding, thereby rendering the cymbal transducer ineffective for high-power ultrasonic applications. In this paper, several experimental analyses have been performed, complemented by the use of Abaqus/CAE finite element analysis, in order to develop a high-power ultrasonic cutting device for bone surgery using a new configuration of cymbal transducer, which is optimised for operation at high displacement and high input power. This new transducer uses a combination of a piezoceramic disc with a metal ring as the driver, thereby improving the mechanical coupling with the metal end-cap.

  17. Comparison of the bone anchored hearing aid implantable hearing device with contralateral routing of offside signal amplification in the rehabilitation of unilateral deafness.

    Science.gov (United States)

    Niparko, John K; Cox, Kenneth M; Lustig, Lawrence R

    2003-01-01

    Monaural hearing imposes constraints under many listening conditions. The authors compared the effects of a semi-implantable bone conductor, the Entific bone anchored hearing aid, with conventional contralateral routing of offside signal amplification to assess rehabilitative benefit in adults with unilateral deafness. Prospective trials of subjects with unilateral deafness using benefit surveys, source identification testing, and hearing in noise testing. Tertiary referral center, outpatient surgical and audiologic services. Adults with unilateral deafness (pure tone average >90 dB, SD hearing loss (n = 1), and sudden sensorineural hearing loss with chronic suppurative otitis media (n = 1). Entry criteria included normal hearing in the contralateral ear (pure tone average 80%). Subjects were fitted with contralateral routing of offside signal amplification devices for 1 month and tested with contralateral routing of offside signal before mastoid implantation of the deaf ear, fitting, and testing for bone anchored hearing aid. Subjects' assessment of experience with their devices and patterns of use, 2) source azimuth identification in noise test, and 3) speech discrimination in quiet and in noise under conditions of noise-front, noise-to-normal-ear, and noise-to-deaf-ear. There was consistent satisfaction with bone anchored hearing aid implantation and amplification, and poor acceptance of contralateral routing of offside signal amplification. Sound localization was poor at baseline and with both bone anchored hearing aid and contralateral routing of offside signal. Relative to baseline, contralateral routing of offside signal and bone anchored hearing aid produced significantly better speech recognition in noise under most conditions. The bone anchored hearing aid enabled significantly better speech recognition than contralateral routing of offside signal in quiet and in a composite of noise conditions. The advantages may relate to averting the interference of

  18. Long-term Compliance and Satisfaction With Percutaneous Bone Conduction Devices in Patients With Congenital Unilateral Conductive Hearing Loss.

    Science.gov (United States)

    Nelissen, Rik C; Mylanus, Emmanuel A M; Cremers, Cor W R J; Hol, Myrthe K S; Snik, Ad F M

    2015-06-01

    Patients with congenital unilateral conductive hearing loss (UCHL) can either be watchful monitored or treated surgically through the fitting of a percutaneous bone conduction device (BCD) or, in some cases, atresia repair. The current study evaluated the long-term compliance and satisfaction with a percutaneous BCD in this specific population. Fifty-three consecutive patients with congenital UCHL treated with a percutaneous BCD in our tertiary referral center between 1998 and 2011 were identified. Clinical and audiological data were retrospectively gathered from the patients' files. The patients were interviewed by telephone about their current device usage status and were asked to complete the Speech, Spatial and Qualities of Hearing Scale (SSQ). Compliance with the BCD was 56.6% after a mean follow-up of 7 years. The mean age at implantation of the users (22 years) was significantly higher than that of the nonusers (10 years). The mean time of device usage before the patients stopped using the BCD was 5 years. The primary reasons mentioned for quitting the BCD were experiencing excess background noise and/or subjectively not receiving enough benefit. Objectively measured features of binaural processing affected by the BCD were found to correlate with long-term BCD usage. The SSQ revealed significant improvement in the aided condition compared with the nonaided condition in the users, in contrast to the nonusers. The current disappointing long-term compliance figures indicate the need for an even more careful and individualized approach with life-long follow-up when fitting BCDs in this specific population, especially in children.

  19. 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.

  20. A Biomechanical Comparison of Fifth Metatarsal Jones Fracture Fixation Methods.

    Science.gov (United States)

    Duplantier, Neil L; Mitchell, Ronald J; Zambrano, Steve; Stone, Aaron C; Delgado, Domenica A; Lambert, Bradley S; Moreno, Michael R; Harris, Joshua D; McCulloch, Patrick C; Lintner, David M; Varner, Kevin E

    2018-04-01

    Fifth metatarsal base fractures of the metaphyseal-diaphyseal watershed junction (Jones fracture) are commonly treated with surgical fixation in athletes. Intramedullary screw fixation remains the most utilized construct, although plantar-lateral plating is an alternative. Purpose/Hypothesis: The purpose was to compare the mechanical strength of fracture fixation between an intramedullary screw and plantar-lateral plating. The hypothesis was that plantar-lateral plate fixation would allow for more cycles and higher peak loads before failure, as well as less fracture gapping, than would an intramedullary screw in cadaveric foot specimens with simulated Jones fractures exposed to cantilever bending. Controlled laboratory study. Twelve pairs of male cadaver feet were separated into 2 groups (plate or screw) to conduct contralateral comparative testing of 2 devices with equally numbered right and left feet. For each fifth metatarsal, an osteotomy with a microsagittal saw was created to simulate a Jones fracture. The plate group underwent fixation with a 3.0-mm 4-hole low-profile titanium plate placed plantar-laterally with 3 locking screws and 1 nonlocking screw. The screw group underwent fixation with a 40- or 45-mm × 5.5-mm partially threaded solid titanium intramedullary screw. After fixation, the metatarsals were excised for biomechanical testing. Cyclic cantilever failure testing was conducted with a gradient-cycle method. Sinusoidal loading forces were applied, increasing by 5.0-pound-force increments per 10 cycles, until each specimen experienced mechanical failure of implant or bone. Failure mode, number of cycles to failure, peak failure load, gap width at the last mutual prefailure loading, and video data were recorded. Paired 2-tailed t test (α = 0.05) was used to compare groups ( P Plate fixation resulted in significantly higher mean ± SD values for cycles to failure (63.9 ± 27.0 vs 37.3 ± 36.9, P = .01) and peak failure load (159.2 ± 60.5 N vs 96.5

  1. Biologic and biomechanic evaluation of posterior lumbar fusion in the rabbit. The effect of fixation rigidity.

    Science.gov (United States)

    Feighan, J E; Stevenson, S; Emery, S E

    1995-07-15

    The histologic and biomechanic characteristics of posterior lumbar fusion with varying rigidity of a novel internal fixation construct in the rabbit were analyzed. To evaluate this rabbit model for future studies of fusion augmentation. Previous studies in goats and dogs showed internal fixation enhances spinal arthrodesis. Twenty eight New Zealand white rabbits underwent a posterior midline fusion from L4 to L6. Some animals received autogenous iliac crest bone graft, stabilized by wiring the superior facets bilaterally, and supplementation with polymethylmethacrylate. The experimental groups were iliac crest bone graft with either no fixation, wire fixation, or wire and polymethylmethacrylate fixation; and no graft and either no fixation, wire fixation, or wire and polymethylmethacrylate fixation. Animals were killed 2 months after surgery, and the specimens were nondestructively tested biomechanically for stiffness in six modes (flexion, extension, left and right bending, compression, and torsion) and histologically for evidence of fusion, revascularization, and new bone formation. Fusions with either wire or wire and polymethylmethacrylate fixation were significantly stiffer than those without fixation (P < 0.05). There was no statistical difference between the iliac crest bone graft and wire group and the iliac crest bone graft, wire, and polymethylmethacrylate group in the modes tested. Nine of 14 motion segments receiving the stiffest construct (iliac crest bone graft, wire, and polymethylmethacrylate) had evidence of solid bony fusion. None of the 12 motion segments receiving iliac crest bone graft and wire had evidence of bony fusion, but five had a fibrocartilage union with some ossification present. Eight of 12 motion segments receiving iliac crest bone graft and no fixation had predominantly fibrous unions with some fibrocartilage, and only one motion segment of 12 showed bony fusion. This study suggests that more rigid fixation produces more successful

  2. LCP external fixation - External application of an internal fixator: two cases and a review of the literature

    Directory of Open Access Journals (Sweden)

    Wong Merng-Koon

    2010-03-01

    Full Text Available Abstract The locking compression plate (LCP is an angle-stable fixator intended for intracorporeal application. In selected cases, it can be applied externally in an extracorporeal location to function as a monolateral external fixator. We describe one patient with Schatzker V tibial plateau fracture and one patient with Gustillo IIIB open tibia shaft fracture treated initially with traditional external fixation for whom exchange fixation with externally applied LCPs was performed. The first case went on to bony union while the second case required bone grafting for delayed union. Both patients found that the LCP external fixators facilitated mobilization and were more manageable and aesthetically acceptable than traditional bar-Schanz pin fixators.

  3. [Ilizarov fixation of supramalleolar fractures].

    Science.gov (United States)

    Mseddi, M B E; Mseddi, M; Siala, A; Dahmene, J; Ben Hamida, R; Ben Ayeche, M

    2005-02-01

    Supramalleolar fractures are generally considered to be a difficult surgical challenge because they occur in a area where the tibia lies superficially with a precarious blood supply to the skin, exposing to the risk of infection and necrosis after internal fixation. These fractures are also situated close to the tibiotalar joint making centromedullary nailing difficult, even with distal locking. The Ilizarov external fixator could be an attractive alternative in this indication. We report a series of 17 supramalleolar fractures in 17 patients, 14 men and 3 women, treated with the Ilizarov external fixator between 1991 and 2001. Most were traffic accident victims and most had complex fractures resulting from high-energy trauma. There were many associated lesions. Fractures were open in ten patients. The Ilizarov fixator was used as the first intention treatment in seven patients and as a second line treatment in ten. The system allowed early weight bearing in all patients. Tolerance was generally good with a relatively low rate of superficial pin track infections (two cases). There was one case of osteitis which developed in a patient with an open fracture. There were no thromboembolic complications and no nerve involvement. Bone healing was achieved within three months in thirteen patients. There were three cases of late healing which were treated by the ascension technique using a cancellous graft and fibular osteotomy. The overall healing rate with this method was 94%. The one case of nonunion was successfully treated with an inter tibiofibular graft. The overall functional outcome was satisfactory in 76% of the patients, based on the Alho-Klemm criteria. Axial deformation predominated in the frontal plane: three patients had > 10 degrees varus in one case. These results could be improved by better operative technique. We advocate installing the patient in the supine position with transcalcaneal traction allowing good restitution of the leg axis. The assembly

  4. Unicortical self-drilling external fixator pins reduce thermal effects during pin insertion.

    Science.gov (United States)

    Greinwald, Markus; Varady, Patrick A; Augat, Peter

    2017-12-14

    External fixation is associated with the risk of pin loosening and pin infection potentially associated to thermal bone necrosis during pin insertion. This study aims to investigate if the use of external fixator systems with unicortical pins reduces the heat production during pin insertion compared to fixators with bicortical pins. Porcine bone specimens were employed to determine bone temperatures during insertion of fixator pins. Two thermographic cameras were used for a simultaneous temperature measurement on the bone surface (top view) and a bone cross-section (front view). Self-drilling unicortical and bicortical pins were inserted at different rotational speeds: (30-600) rpm. Maximum and mean temperatures of the emerging bone debris, bone surface and bone cross-section were analyzed. Maximum temperatures of up to 77 ± 26 °C were measured during pin insertion in the emerging debris and up to 42 ± 2 °C on the bone surface. Temperatures of the emerging debris increased with increasing rotational speeds. Bicortical pin insertion generated significantly higher temperatures at low insertion speed (30 rpm) CONCLUSION: The insertion of external fixator pins can generate a considerable amount of heat around the pins, primarily emerging from bone debris and at higher insertion speeds. Our findings suggest that unicortical, self-drilling fixator pins have a decreased risk for thermal damage, both to the surrounding tissue and to the bone itself.

  5. Distal biceps brachii tendon repairs: a single-incision technique using a cortical button with interference screw versus a double-incision technique using suture fixation through bone tunnels.

    Science.gov (United States)

    Shields, Edward; Olsen, Joshua R; Williams, Richard B; Rouse, Lucien; Maloney, Michael; Voloshin, Ilya

    2015-05-01

    Distal biceps brachii tendon repairs performed with a tension slide technique using a cortical button (CB) and interference screw are stronger than those based on suture fixation through bone tunnels (BTs) in biomechanical studies. However, clinical comparison of these 2 techniques is lacking in the literature. To perform a clinical comparison of the single-incision CB and double-incision BT techniques. Cohort study; Level of evidence, 3. Distal biceps tendon ruptures repaired through either the single-incision CB or double-incision BT technique were retrospectively identified at a single institution. Patients>1 year out from surgery were assessed for range of motion, strength, and complications, and they completed a DASH questionnaire (Disabilities of the Arm, Shoulder, and Hand). Patients in the CB group (n=20) were older (52±9.5 vs 43.7±8.7 years; P=.008), had a shorter interval from surgery to evaluation (17.7±5 vs 30.8±16.5 months; P=.001), and were less likely to smoke (0% vs 28.5%; P=.02) compared with the BT patients (n=21). DASH scores were similar between groups (4.46±4.4 [CB] vs 5.7±7.5 [BT]; P=.65). Multivariate analysis revealed no differences in range of motion or strength between groups. More CB patients (30%; n=6) experienced a complication compared with those in the BT group (4.8%; n=1) (P=.04), and these complications were predominantly paresthesias of the superficial radial nerve that did not resolve. There were no reoperations or repair failures in either group. Both the single-incision CB and double-incision BT techniques provided excellent clinical results. Complications were more common in the single-incision CB group and most commonly involved paresthesias of the superficial radial nerve. © 2015 The Author(s).

  6. OSTEOSYNTHESIS OF THE METACARPAL BONE WITH BIOABSORBABLE MATERIALS: A CASE REPORTS

    Directory of Open Access Journals (Sweden)

    Ernest Novak

    2004-04-01

    Full Text Available Background. Recent advances in biomaterial technology make it possible to produce easy-to-handle implants for osteosynthesis with ultra-high strenght and excellent biocompatibility. Biomechanical studies have shown that fixation rigidity achieved with self-reinforced (SR pins, screws and miniplates is comparable with that of metallic fixation methods. Internal fixation by means of bioabsorbable plates, screws, and pins can be used to stabilize some fractures of small bones in the hand.We report our experience with three cases where internal fixation with a SR (poly-L/DL-lactide 70/30; SR-P (L/DL LA 70/30, BioSorbTMFX miniplates and screws was carried out for stabilization of a metacarpal shaft fracture and thumb replantation.Conclusions. After bone healing is complete, metallic osteosynthesis devices become unnecessary or can even be harmful. Metallic implant-related long-term complications and secondary removal operation are avoided by using of bioabsorbable osteosynthesis devices for metacarpal bones osteosynthesis.

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

    International Nuclear Information System (INIS)

    Peterson, P.R.; Pascoe, J.R.; Wheat, J.D.

    1987-01-01

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

  8. External fixation for phalangeal and metacarpal fractures

    NARCIS (Netherlands)

    Drenth, DJ; Klasen, HJ

    From 1987 to 1993 we treated 33 patients with 29 phalangeal and seven metacarpal fractures by external fixation using a mini-Hoffmann device. There were 27 open and 25 comminuted fractures, In 12 patients one or more tendons was involved, The mean follow-up was 4.4 years, Complications occurred in

  9. Correlation Between Bone Density and Instantaneous Torque at Implant Site Preparation: A Validation on Polyurethane Foam Blocks of a Device Assessing Density of Jawbones.

    Science.gov (United States)

    Di Stefano, Danilo Alessio; Arosio, Paolo

    2016-01-01

    Bone density at implant placement sites is one of the key factors affecting implant primary stability, which is a determinant for implant osseointegration and rehabilitation success. Site-specific bone density assessment is, therefore, of paramount importance. Recently, an implant micromotor endowed with an instantaneous torque-measuring system has been introduced. The aim of this study was to assess the reliability of this system. Five blocks with different densities (0.16, 0.26, 0.33, 0.49, and 0.65 g/cm(3)) were used. A single trained operator measured the density of one of them (0.33 g/cm(3)), by means of five different devices (20 measurements/device). The five resulting datasets were analyzed through the analysis of variance (ANOVA) model to investigate interdevice variability. As differences were not significant (P = .41), the five devices were each assigned to a different operator, who collected 20 density measurements for each block, both under irrigation (I) and without irrigation (NI). Measurements were pooled and averaged for each block, and their correlation with the actual block-density values was investigated using linear regression analysis. The possible effect of irrigation on density measurement was additionally assessed. Different devices provided reproducible, homogenous results. No significant interoperator variability was observed. Within the physiologic range of densities (> 0.30 g/cm(3)), the linear regression analysis showed a significant linear correlation between the mean torque measurements and the actual bone densities under both drilling conditions (r = 0.990 [I], r = 0.999 [NI]). Calibration lines were drawn under both conditions. Values collected under irrigation were lower than those collected without irrigation at all densities. The NI/I mean torque ratio was shown to decrease linearly with density (r = 0.998). The mean error introduced by the device-operator system was less than 10% in the range of normal jawbone density

  10. Guide to radiation fixatives

    International Nuclear Information System (INIS)

    Tawil, J.J.; Bold, F.C.

    1983-11-01

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

  11. Guide to radiation fixatives

    Energy Technology Data Exchange (ETDEWEB)

    Tawil, J.J.; Bold, F.C.

    1983-11-01

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

  12. 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.

  13. Fractures of the Proximal Fifth Metatarsal: Percutaneous Bicortical Fixation

    OpenAIRE

    Mahajan, Vivek; Chung, Hyun Wook; Suh, Jin Soo

    2011-01-01

    Background Displaced intraarticular zone I and displaced zone II fractures of the proximal fifth metatarsal bone are frequently complicated by delayed nonunion due to a vascular watershed. Many complications have been reported with the commonly used intramedullary screw fixation for these fractures. The optimal surgical procedure for these fractures has not been determined. All these observations led us to evaluate the effectiveness of percutaneous bicortical screw fixation for treating these...

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

    Directory of Open Access Journals (Sweden)

    Riediger Dieter

    2008-05-01

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

  15. Predisposing factors for adverse skin reactions with percutaneous bone anchored hearing devices implanted with skin reduction techniques.

    Science.gov (United States)

    Candreia, Claudia; Birrer, Ruth; Fistarol, Susanna; Kompis, Martin; Caversaccio, Marco; Arnold, Andreas; Stieger, Christof

    2016-12-01

    We present an analysis of adverse events after implantation of bone anchored hearing device in our patient population with focus on individual risk factors for peri-implant skin reactions. The investigation involved a chart review of adult Baha patients (n = 179) with 203 Bahas implanted with skin reduction techniques between 1993 and 2009, a questionnaire (n = 97) and a free clinical examination (n = 47). Skin reactions were graded by severity from 0 (no skin reaction) to 4 (implant loss resulting from infection) according to Holgers. We analyzed the skin reaction rate (SRR) defined as the number of skin reactions per year and the worst Holgers grade (WHG), which indicates the grade of the worst skin reaction per implant. We defined 20 parameters including the demographic characteristics, surgery details, subjective benefits, handling and individual factors. The most frequent adverse events (85 %) were skin reactions. The average SRR was 0.426 per Baha year. Six parameters showed an association with the SRR or the WHG. The clinically most relevant factors are an elevated Body Mass Index (BMI, p = 0.02) and darker skin type (p = 0.03). The SRR increased with the distance between the tragus and the implant (p = 0.02). Regarding the identified risk factors, the SRR might be reduced by selecting a location for the implant near the pinna and by specific counseling regarding post-operative care for patients with darker skin type or an elevated Body Mass Index (BMI). Few of the factors analyzed were found to influence the SRR and WHG. Since most adverse skin reactions could be treated easily with local therapy, our results suggest that in adult patients, individual risk factors for skin reactions are not a contraindication for Baha implantation. Thus, patients can be selected purely on audiological criteria.

  16. Biomechanical study of posterior wall acetabular fracture fixation using acetabular tridimensional memory alloy-fixation system.

    Science.gov (United States)

    Xin-wei, Liu; Shuo-gui, Xu; Chun-cai, Zhang; Qing-ge, Fu; Pan-feng, Wang

    2010-05-01

    We developed the acetabular tridimensional memory alloy-fixation system (ATMFS), which is made of NiTi shape memory alloy, according to the specific mechanical properties of biological memory material, nitinol alloy and measured distribution of contact area and pressure between the acetabulum and the femoral head of cadaveric pelvis. Six formalin-preserved cadaveric pelvis 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 pelvis 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; (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 40-90 degrees about the acetabular rim. Creation of a posterior wall defect resulted in increased load in the superior acetabulum (1422N) as compared to the intact condition (762N, P=0.007). Following reduction and internal fixation, the load distributed to the superior acetabulum (1486N) was not statistically different from the defect condition. Following the fixation with ATMFS, the load seen at the superior region of the actabulum (936N) was less than fixation with reconstruction plate and was not different from intact state (P=0.4). 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. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Removal of symptomatic titanium fixation plates after craniotomy.

    Science.gov (United States)

    Gupta, Raghav; Adeeb, Nimer; Griessenauer, Christoph J; Moore, Justin M; Patel, Apar S; Thomas, Ajith J; Ogilvy, Christopher S

    2016-10-01

    Titanium fixation plates are routinely used for rigid fixation of bone flaps after craniotomy. In craniofacial surgery or after craniotomy involving orbitozygomatic osteotomies, these plates are occasionally removed because of infection, pain, protrusion, soft tissue erosion, and plate malfunction. However, plate removal because of pain and protrusion after craniotomy without orbitozygomatic osteotomy has rarely been reported. A retrospective analysis of all patients who underwent removal of cranial fixation plates after craniotomy, performed by the senior authors at one institution between 2014 and 2016, was conducted. A total of 319 patients underwent bone flap fixation after craniotomy using cranial fixation plates between 2014 and 2016. Five of those patients (1.6 %) had their cranial plates removed because of pain and protrusion. An additional four patients had a cranial fixation plate removed during that time frame with the original craniotomy performed before 2014. All nine patients had immediate resolution of symptoms after plate removal. We report our experience with cranial fixation plate removal because of pain and protrusion in patients who underwent craniotomy without orbitozygomatic osteotomy, particularly frontotemporal craniotomy. In an attempt to reduce this complication, we recently stopped placing a full-size burr hole in the keyhole area of a frontotemporal craniotomy, eliminating the need for a titanium burr hole cover plate.

  18. CSF coccidioides complement fixation

    Science.gov (United States)

    Skip navigation U.S. National Library of Medicine The navigation menu has been collapsed. ... of this page: //medlineplus.gov/ency/article/003526.htm CSF coccidioides complement fixation test To use the sharing features ...

  19. Histoplasma complement fixation

    Science.gov (United States)

    Skip navigation U.S. National Library of Medicine The navigation menu has been collapsed. ... this page: //medlineplus.gov/ency/article/003527.htm Histoplasma complement fixation To use the sharing features on this page, ...

  20. 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....... 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....

  1. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

    OpenAIRE

    Wegner, Alexander; Kauther, Max Daniel; Landgraeber, Stefan; von Knoch, Marius

    2012-01-01

    Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operativ...

  2. The efficacy of rotational control designs in promoting torsional stability of hip fracture fixation.

    Science.gov (United States)

    Gosiewski, J D; Holsgrove, T P; Gill, H S

    2017-05-01

    Fractures of the proximal femur are a common clinical problem, and a number of orthopaedic devices are available for the treatment of such fractures. The objective of this study was to assess the rotational stability, a common failure predictor, of three different rotational control design philosophies: a screw, a helical blade and a deployable crucifix. Devices were compared in terms of the mechanical work (W) required to rotate the implant by 6° in a bone substitute material. The substitute material used was Sawbones polyurethane foam of three different densities (0.08 g/cm 3 , 0.16 g/cm 3 and 0.24 g/cm 3 ). Each torsion test comprised a steady ramp of 1°/minute up to an angular displacement of 10°. The deployable crucifix design (X-Bolt), was more torsionally stable, compared to both the dynamic hip screw (DHS, p = 0.008) and helical blade (DHS Blade, p= 0.008) designs in bone substitute material representative of osteoporotic bone (0.16 g/cm 3 polyurethane foam). In 0.08 g/cm 3 density substrate, the crucifix design (X-Bolt) had a higher resistance to torsion than the screw (DHS, p = 0.008). There were no significant differences (p = 0.101) between the implants in 0.24 g/cm 3 density bone substitute. Our findings indicate that the clinical standard proximal fracture fixator design, the screw (DHS), was the least effective at resisting torsional load, and a novel crucifix design (X-Bolt), was the most effective design in resisting torsional load in bone substitute material with density representative of osteoporotic bone. At other densities the torsional stability was also higher for the X-Bolt, although not consistently significant by statistical analysis. Cite this article : J. D. Gosiewski, T. P. Holsgrove, H. S. Gill. The efficacy of rotational control designs in promoting torsional stability of hip fracture fixation. Bone Joint Res 2017;6:270-276. DOI: 10.1302/2046-3758.65.BJR-2017-0287.R1. © 2017 Gosiewski et al.

  3. Custom-made titanium devices as membranes for bone augmentation in implant treatment: Modeling accuracy of titanium products constructed with selective laser melting.

    Science.gov (United States)

    Otawa, Naruto; Sumida, Tomoki; Kitagaki, Hisashi; Sasaki, Kiyoyuki; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Nakamura, Takashi; Yamada, Tomohiro; Mori, Yoshihide; Matsushita, Tomiharu

    2015-09-01

    The purpose of this study was to verify the modeling accuracy of various products, and to produce custom-made devices for bone augmentation in individual patients requiring implantation. Two-(2D) and three-dimensional (3D) specimens and custom-made devices that were designed as membranes for guided bone regeneration (GBR) were produced using a computer-aided design (CAD) and rapid prototyping (RP) method. The CAD design was produced using a 3D printing machine and selective laser melting (SLM) with pure titanium (Ti) powder. The modeling accuracy was evaluated with regard to: the dimensional accuracy of the 2D and 3D specimens; the accuracy of pore structure of the 2D specimens; the accuracy of porosity of the 3D specimens; and the error between CAD design and the scanned real product by overlapped images. The accuracy of the 2D and 3D specimens indicated precise results in various parameters, which were tolerant in ISO 2768-1. The error of overlapped images between the CAD and scanned data indicated that accuracy was sufficient for GBR. In integrating area of all devices, the maximum and average error were 292 and 139 μm, respectively. High modeling accuracy can be achieved in various products using the CAD/RP-SLM method. These results suggest the possibility of clinical applications. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  4. Quantification of bone quality using different cone beam computed tomography devices: Accuracy assessment for edentulous human mandibles

    OpenAIRE

    Van Dessel, Jeroen; Nicolielo, Laura Ferreira Pinheiro; Huang, Yan; Slagmolen, Pieter; Politis, Constantinus; Lambrichts, Ivo; Jacobs, Reinhilde

    2016-01-01

    Purpose: To determine the accuracy of the latest cone beam computed tomography (CBCT) machines in comparison to multi-slice computer tomography (MSCT) and micro computed tomography (micro CT) for objectively assessing trabecular and cortical bone quality prior to implant placement. Materials and methods: Eight edentulous human mandibular bone samples were scanned with seven CBCT scanners (3D Accuitomo 170, i-CAT Next Generation, ProMax 3D Max, Scanora 3D, Cranex 3D, Newtom GiANO and Carestrea...

  5. The principles of interference screw fixation: application to foot and ankle surgery.

    Science.gov (United States)

    Feldman, Kent A

    2005-01-01

    Based on the success of the anterior cruciate ligament model, interference screw fixation is now being applied to a wide variety of orthopedic conditions that require the fixation of tendon or ligament to bone. The primary focus of this article is to present the principles of interference screw fixation. By understanding the principles of interference screw fixation, the foot and ankle surgeon will be able to apply this fixation technique to a wide variety of surgical applications for tendon transfers or ligament repairs. The surgical technique, history, principles of fixation, studies of fixation strength, tissue healing, and foot and ankle indications are reviewed. A modified Girdlestone digital flexor tendon transfer procedure description is included to illustrate how interference screw techniques may be applied to foot surgery.

  6. Midterm results of biologic fixation or mosaicplasty and drilling in osteochondritis dissecans

    Directory of Open Access Journals (Sweden)

    Tuluhan Yunus Emre

    2011-01-01

    Conclusion: Biologic fixation or mosaicplasty and drilling as a technique to treatment of the lesion in OCD by osteochondral autograft transfer has resulted in good and excellent clinical outcomes in our patients and it is considered that providing blood flow to subchondral bone by circumferencial drilling leads to an increase in the robustness of biological internal fixation and shortens the duration of recovery.

  7. 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.

  8. Biomechanical effects of hybrid stabilization on the risk of proximal adjacent-segment degeneration following lumbar spinal fusion using an interspinous device or a pedicle screw-based dynamic fixator.

    Science.gov (United States)

    Lee, Chang-Hyun; Kim, Young Eun; Lee, Hak Joong; Kim, Dong Gyu; Kim, Chi Heon

    2017-12-01

    OBJECTIVE Pedicle screw-rod-based hybrid stabilization (PH) and interspinous device-based hybrid stabilization (IH) have been proposed to prevent adjacent-segment degeneration (ASD) and their effectiveness has been reported. However, a comparative study based on sound biomechanical proof has not yet been reported. The aim of this study was to compare the biomechanical effects of IH and PH on the transition and adjacent segments. METHODS A validated finite element model of the normal lumbosacral spine was used. Based on the normal model, a rigid fusion model was immobilized at the L4-5 level by a rigid fixator. The DIAM or NFlex model was added on the L3-4 segment of the fusion model to construct the IH and PH models, respectively. The developed models simulated 4 different loading directions using the hybrid loading protocol. RESULTS Compared with the intact case, fusion on L4-5 produced 18.8%, 9.3%, 11.7%, and 13.7% increments in motion at L3-4 under flexion, extension, lateral bending, and axial rotation, respectively. Additional instrumentation at L3-4 (transition segment) in hybrid models reduced motion changes at this level. The IH model showed 8.4%, -33.9%, 6.9%, and 2.0% change in motion at the segment, whereas the PH model showed -30.4%, -26.7%, -23.0%, and 12.9%. At L2-3 (adjacent segment), the PH model showed 14.3%, 3.4%, 15.0%, and 0.8% of motion increment compared with the motion in the IH model. Both hybrid models showed decreased intradiscal pressure (IDP) at the transition segment compared with the fusion model, but the pressure at L2-3 (adjacent segment) increased in all loading directions except under extension. CONCLUSIONS Both IH and PH models limited excessive motion and IDP at the transition segment compared with the fusion model. At the segment adjacent to the transition level, PH induced higher stress than IH model. Such differences may eventually influence the likelihood of ASD.

  9. Improving carbon fixation pathways

    Energy Technology Data Exchange (ETDEWEB)

    Ducat, DC; Silver, PA

    2012-08-01

    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 and enhancing photosynthetic reactions in a species independent manner. Furthermore, the elucidation of alternative carbon-fixation routes distinct from the Calvin cycle raises possibilities that novel pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials.

  10. A guided surgical approach and novel fixation method for arthroscopic Latarjet.

    Science.gov (United States)

    Boileau, Pascal; Gendre, Patrick; Baba, Mohammed; Thélu, Charles-Édouard; Baring, Toby; Gonzalez, Jean-François; Trojani, Christophe

    2016-01-01

    Most of the complications of the Latarjet procedure are related to the bone block positioning and use of screws. The purpose of this study was to evaluate if an arthroscopic Latarjet guiding system improves accuracy of bone block positioning and if suture button fixation could be an alternative to screw fixation in allowing bone block healing and avoiding complications. Seventy-six patients (mean age, 27 years) underwent an arthroscopic Latarjet procedure with a guided surgical approach and suture button fixation. Bone graft union and positioning accuracy were assessed by postoperative computed tomography imaging. Clinical examinations were performed at each visit. At a mean of 14 months (range, 6-24 months) postoperatively, 75 of 76 patients had a stable shoulder. No neurologic complications were observed; no patients have required further surgery. The coracoid graft was positioned strictly tangential to the glenoid surface in 96% of the cases and below the equator in 93%. The coracoid graft healed in 69 patients (91%). A guided surgical approach optimizes graft positioning accuracy. Suture button fixation can be an alternative to screw fixation, obtaining an excellent rate of bone union. Neurologic and hardware complications, classically reported with screw fixation, have not been observed with this guided technique and novel fixation method. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Sclerostin antibody treatment improves implant fixation in a model of severe osteoporosis.

    Science.gov (United States)

    Virdi, Amarjit S; Irish, John; Sena, Kotaro; Liu, Min; Ke, Hua Zhu; McNulty, Margaret A; Sumner, Dale R

    2015-01-21

    The mechanical fixation of orthopaedic and dental implants is compromised by diminished bone volume, such as with osteoporosis. Systemic administration of sclerostin antibody (Scl-Ab) has been shown to enhance implant fixation in normal animals. In the present study, we tested whether Scl-Ab can improve implant fixation in established osteoporosis in a rat model. We used an ovariectomized (ovx) rat model, in which we found a 78% decrease in trabecular bone volume at the time of implant surgery; sham-ovx, age-matched rats were used as controls. After placement of a titanium implant in the medullary cavity of the distal aspect of the femur, the rats were maintained for four, eight, or twelve weeks and treated biweekly with Scl-Ab or with the delivery vehicle alone. Outcomes were measured with use of microcomputed tomography, mechanical testing, and static and dynamic histomorphometry. Scl-Ab treatment doubled implant fixation strength in both the sham-ovx and ovx groups, although the enhancement was delayed in the ovx group. Scl-Ab treatment also enhanced bone-implant contact; increased peri-implant trabecular thickness and volume; and increased cortical thickness. These structural changes were associated with an approximately five to sevenfold increase in the bone-formation rate and a >50% depression in the eroded surface following Scl-Ab treatment. Trabecular bone thickness and bone-implant contact accounted for two-thirds of the variance in fixation strength. In this model of severe osteoporosis, Scl-Ab treatment enhanced implant fixation by stimulating bone formation and suppressing bone resorption, leading to enhanced bone-implant contact and improved trabecular bone volume and architecture. Systemic administration of anti-sclerostin antibodies might be a useful strategy in total joint replacement when bone mass is deficient. Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.

  12. Monitoring in vivo load transmission through an external fixator.

    Science.gov (United States)

    Grasa, J; Gómez-Benito, M J; González-Torres, L A; Asiaín, D; Quero, F; García-Aznar, J M

    2010-03-01

    This work presents a portable non-invasive external fixator to assess and monitor fracture healing in real time. To evaluate the potential of this fixator, a transverse osteotomy was performed in the tibia of six adult sheep (mean age 3+/-0.5 years and weight 63+/-5 kg). The fractures were stabilized by a specially designed unilateral external fixator, which was instrumented by means of a set of strain gauges. Strains in the external surface of the fixator were monitored during all the healing process. A wireless, remote monitoring of the implant was developed through a specially designed external telemetric device. The strain gauges were arranged in two different half-bridge Wheatstone configurations, allowing easy post-processing of the signal. Thus, bending loads were measured in two planes of the external fixator acting as a load cell. The load through the fixator was evaluated for the gait cycle during all the healing process. Full weight bearing of the injured leg was observed from the beginning. The load transmission mechanism in the fixator was quite similar in all operated tibias and radiographic images showed a successful healing in all animals. Although the fixator has only been tested in an animal model, after further testing this system may have clinical potential.

  13. Management of Postoperative Spondylodiscitis with and without Internal Fixation.

    Science.gov (United States)

    Wang, Xiang; Tao, Hairong; Zhu, Yanhui; Lu, Xiongwei; Hu, Xiaopeng

    2015-01-01

    Postoperative spondylodiscitis is relatively uncommon. This complication is associated with increased cost, and long-term of inability to work, and even morbidity. Although the majority of postoperative spondylodiscitis cases can be well managed by conservative treatment, postoperative spondylodiscitis after internal fixation and those cases that are unresponsive to the conservative treatment present challenges to the surgeon. Here, a review was done to analyze the treatment of postoperative spondylodiscitis with/without internal fixation. This review article suggested that majority of postoperative spondylodiscitis without internal fixation could be cured by conservative treatment. Either posterior or anterior debridement can be used to treat postoperative spondylodiscitis without internal fixation when conservative treatment fails. In addition, minimally invasive debridement and drainage may also be an alternative treatment. In case of postoperative spondylodiscitis after internal fixation, surgical treatment was required. In the cervical spine, it can be well managed by anterior debridement, removal of internal fixation, and reconstruction of the spinal stability by using bone grafting/cage/anterior plate. Postoperative spondylodiscitis after internal fixation is successfully managed by combined anterior debridement, fusion with posterior approach and removal of pedicle screw or extension of pedicle screw beyond the lesion site, in the thoracic and lumbar spine.

  14. Objective and Subjective Outcome of a New Transcutaneous Bone Conduction Hearing Device: Half-year Follow-up of the First 12 Nordic Implantations.

    Science.gov (United States)

    Eberhard, Kristine Elisabeth; Olsen, Steen Østergaard; Miyazaki, Hidemi; Bille, Michael; Caye-Thomasen, Per

    2016-03-01

    To examine the objective and subjective outcome of a new transcutaneous bone conduction hearing device. Prospective, consecutive case series. Twelve patients were implanted. Eight patients had a conductive/mixed (con/mix) hearing loss. Four had single sided deafness. At half-year follow-up, aided and unaided sound field hearing was evaluated by 1) warble tone thresholds, 2) pure-tone average (PTA4), 3) speech discrimination score (SDS) in quiet, and 4) speech reception threshold 50% at 70 dB SPL noise level (SRT50%). Subjective outcome was evaluated by three questionnaires: 1) International Outcome Inventory for Hearing Aids, 2) Speech, Spatial and Qualities of Hearing Scale 12, and 3) a questionnaire on frequency and duration of use. No major complications occurred. The mean aided PTA4 was lowered by 23dB. SDS was increased by 40% 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 to beneficial outcome. In Speech, Spatial and Qualities of Hearing Scale 12, "quality of hearing" scored especially high. The con/mix hearing loss group showed larger benefit especially in SDS, SRT50% in noise and the subjective evaluations, whereas frequency and duration of use were similar. This study on the first 12 Nordic patients implanted with a new transcutaneous bone conduction hearing device demonstrates significant objective, as well as subjective hearing benefit. Patient satisfaction was high, as was the frequency of use.

  15. Update: Biological Nitrogen Fixation.

    Science.gov (United States)

    Wiseman, Alan; And Others

    1985-01-01

    Updates knowledge on nitrogen fixation, indicating that investigation of free-living nitrogen-fixing organisms is proving useful in understanding bacterial partners and is expected to lead to development of more effective symbioses. Specific areas considered include biochemistry/genetics, synthesis control, proteins and enzymes, symbiotic systems,…

  16. Biomechanical analysis of titanium fixation plates and screws in ...

    African Journals Online (AJOL)

    fast bone healing, to avoid postoperative intermaxillary fixation, and to initiate early postoperative mandibular function and oral hygiene. Postoperative skeletal ..... torsion on the condyle, and less risk of inferior alveolar nerve injury. It is particularly advantageous in larger advancements where proximal and distal overlap is ...

  17. Parametric analysis of glenoid implant design and fixation type.

    Science.gov (United States)

    Geraldes, Diogo M; Hansen, Ulrich; Amis, Andrew A

    2017-04-01

    Common post-operative problems in shoulder arthroplasty such as glenoid loosening and joint instability may be reduced by improvements in glenoid design, shape, material choice, and fixation method. A framework for parametric analysis of different implant fixation configurations was developed in order to efficiently sift through potential glenoid component designs. We investigated the influence of design factors such as fixation type, component thickness, and peg position, number, diameter, and length in a multi-factorial design investigation. The proposed method allowed for simultaneous comparison of the mechanical performance of 344 different parametric variations of 10 different reference geometries with either large central fixation features or small peripheral pegs, undergoing four different worst-case scenario loading conditions, and averaging 64.7 s per model. The impact of design parameters were assessed for different factors responsible for post-operative problems in shoulder arthroplasty, such as bone volume preservation, stresses in the implant, central displacement or fixation stability, and the worst performing geometries all relied on conventional central fixation. Of the remaining geometries, four peripheral fixation configurations produced von Mises stresses comfortably below the material's yield strength. We show that the developed method allows for simple, direct, rapid, and repeatable comparison of different design features, material choices, or fixation methods by analyzing how they influence the bone-implant mechanical environment. The proposed method can provide valuable insight in implant design optimization by screening through multiple potential design modifications at an early design evaluation stage and highlighting the best performing combinations according to the failure mechanism to mitigate. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:775-784, 2017. © 2016 Orthopaedic Research Society

  18. Biomechanical Comparison of External Fixation and Compression Screws for Transverse Tarsal Joint Arthrodesis.

    Science.gov (United States)

    Latt, L Daniel; Glisson, Richard R; Adams, Samuel B; Schuh, Reinhard; Narron, John A; Easley, Mark E

    2015-10-01

    Transverse tarsal joint arthrodesis is commonly performed in the operative treatment of hindfoot arthritis and acquired flatfoot deformity. While fixation is typically achieved using screws, failure to obtain and maintain joint compression sometimes occurs, potentially leading to nonunion. External fixation is an alternate method of achieving arthrodesis site compression and has the advantage of allowing postoperative compression adjustment when necessary. However, its performance relative to standard screw fixation has not been quantified in this application. We hypothesized that external fixation could provide transverse tarsal joint compression exceeding that possible with screw fixation. Transverse tarsal joint fixation was performed sequentially, first with a circular external fixator and then with compression screws, on 9 fresh-frozen cadaveric legs. The external fixator was attached in abutting rings fixed to the tibia and the hindfoot and a third anterior ring parallel to the hindfoot ring using transverse wires and half-pins in the tibial diaphysis, calcaneus, and metatarsals. Screw fixation comprised two 4.3 mm headless compression screws traversing the talonavicular joint and 1 across the calcaneocuboid joint. Compressive forces generated during incremental fixator foot ring displacement to 20 mm and incremental screw tightening were measured using a custom-fabricated instrumented miniature external fixator spanning the transverse tarsal joint. The maximum compressive force generated by the external fixator averaged 186% of that produced by the screws (range, 104%-391%). Fixator compression surpassed that obtainable with screws at 12 mm of ring displacement and decreased when the tibial ring was detached. No correlation was found between bone density and the compressive force achievable by either fusion method. The compression across the transverse tarsal joint that can be obtained with a circular external fixator including a tibial ring exceeds that

  19. Short-term alendronate treatment does not maintain a residual effect on spinal fusion with interbody devices and bone graft after treatment withdrawal: an experimental study on spinal fusion in pigs.

    Science.gov (United States)

    Huang, Baoding; Zou, Xuenong; Li, Haisheng; Xue, Qingyun; Bünger, Cody

    2013-02-01

    Whether alendronate treatment has a residual effect on bone ingrowth into porous biomaterial in humans or experimental animals after treatment withdrawal is still unknown. The purpose of this study was to investigate bone ingrowth into porous tantalum and carbon fiber interbody implants after discontinuing alendronate treatment in experimental spinal fusion in pigs. Twenty-four pigs were randomly divided into two groups of each 12 pigs. The pigs underwent anterior intervertebral lumbar arthrodeses at L2-3, L4-5 and L6-7. Each level was randomly allocated to one of the three implants: a porous tantalum ring with pedicle screw fixation, a porous tantalum ring or a carbon fiber cage with anterior staple fixation. The central hole of implants was packed with an autograft. Alendronate was given orally for the first 3 months to one of the two groups. The pigs were observed for 6 months postoperatively. Histology and micro-CT scans were done at the endpoint. The spinal fusion rates of each implant showed no differences between two treatment groups. Furthermore, no differences were found between two groups as for bone ingrowth into the central holes of implants and bone-implant interface in each implant, or as for the pores of tantalum implants. Trabecular bone microarchitecture in the central hole of the carbon fiber cage did not differ between two treatment groups. The application of ALN, with a dose equivalent to that given to humans during the first 3 months after surgery, does not maintain a residual effect on spinal fusion with porous tantalum ring and autograft after treatment withdrawal in a porcine ALIF model.

  20. Cross-calibration of domestic devices and GE lunar prodigy advance dual-energy X-ray densitometer devices for bone mineral measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Su [Chungbuk Health and Science University, Cheongju (Korea, Republic of); Rho, Young Hoon; Lee, In Ju; Kim, Jung Min [Korea University Graduate School, Seoul (Korea, Republic of); Kim, Kyoung A [CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of); Lee, In Ja [Dongnam Health University, Suwon (Korea, Republic of)

    2017-03-15

    Reliable follow-up of bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) is essential in clinical practice. When there is a difference in the BMD values from DXA systems in the same patient, cross calibration equation is required for the reliable follow-up. Unfortunately, no equation is existed in BMD measure between GE Lunar Prodigy Advance (US, GE Healthcare; LPA) and Osteosys Dexxum T (Korea, Osteosys; ODT) DXA systems. In this study, we evaluate the agreement of BMD values between LPA and ODT and suggest the cross calibration equation using European spine phantom (ESP) with two systems. We performed BMD measurements using ten scans with ESP in each DXA systems. We compared BMD values and calculated cross calibration equation by linear regression analysis. The comparison between the LPA and ODT bone densitometers used the ESP. Compared to the ESP BMD values, ODT underestimated 14.36% and LPA overestimated 12.96%. The average of total BMD measurement values acquired with ODT were 21.44% lower than those from LPA. Cross-calibration equation for LPA and ODT was derived from ESP. We calculated simple cross calibration equation for LPA and ODT DXA systems. Cross-calibration equation is necessary for the reliable follow-up of BMD values in two different systems.

  1. Cross-calibration of domestic devices and GE lunar prodigy advance dual-energy X-ray densitometer devices for bone mineral measurements

    International Nuclear Information System (INIS)

    Kim, Jung Su; Rho, Young Hoon; Lee, In Ju; Kim, Jung Min; Kim, Kyoung A; Lee, In Ja

    2017-01-01

    Reliable follow-up of bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) is essential in clinical practice. When there is a difference in the BMD values from DXA systems in the same patient, cross calibration equation is required for the reliable follow-up. Unfortunately, no equation is existed in BMD measure between GE Lunar Prodigy Advance (US, GE Healthcare; LPA) and Osteosys Dexxum T (Korea, Osteosys; ODT) DXA systems. In this study, we evaluate the agreement of BMD values between LPA and ODT and suggest the cross calibration equation using European spine phantom (ESP) with two systems. We performed BMD measurements using ten scans with ESP in each DXA systems. We compared BMD values and calculated cross calibration equation by linear regression analysis. The comparison between the LPA and ODT bone densitometers used the ESP. Compared to the ESP BMD values, ODT underestimated 14.36% and LPA overestimated 12.96%. The average of total BMD measurement values acquired with ODT were 21.44% lower than those from LPA. Cross-calibration equation for LPA and ODT was derived from ESP. We calculated simple cross calibration equation for LPA and ODT DXA systems. Cross-calibration equation is necessary for the reliable follow-up of BMD values in two different systems

  2. A comparative study in fixation methods of medial malleolus fractures between tension bands wiring and screw fixation.

    Science.gov (United States)

    Mohammed, Ayyoub A; Abbas, Khalid Ahmed; Mawlood, Ammar Salah

    2016-01-01

    The aim of this study is to compare two methods of internal fixations of fractured medial malleolus which are simple screw fixation and tension band wiring. Over 5 years we grouped 20 patients with fractured medial malleolus into two groups of operative treatments, group1 treated by malleolar screw fixation and group2 by tension band wiring. The patients were with same age group, gender, fracture type, and etiology. We use statistical analysis for make a comparative study between the two ways of surgical treatment. The mean time for radiologic bone union was 11.8 weeks in group1 patients and 9.4 weeks in group2 patients (P = 0.03). No patients had any sign of fixation failure or Kirschner wires migration. According to the modified ankle scoring system of Olerud and Molander, excellent and good results were achieved in 80 % in group1 patients and 90 % in group2 patients (P = 0.049). Tension-band wiring may be better treatment option for internal fixation of medial malleolar fractures than screw fixation. From these findings we recommend a further randomized clinical trial of larger number of cases and longer follow-up duration in order to regard tension-band wiring a better operative option for fixation of medial malleolar fractures.

  3. Fixation of displaced subcapital femoral fractures. Compression screw fixation versus double divergent pins.

    Science.gov (United States)

    Christie, J; Howie, C R; Armour, P C

    1988-03-01

    One hundred and twenty-seven consecutive patients with displaced subcapital fractures of the femoral neck (Garden Grade III or IV) all under 80 years of age and independently mobile, were randomly allocated to fixation with either double divergent pins or a single sliding screw-plate device. The incidence of non-union and infection in the sliding screw-plate group was significantly higher, and we believe that when internal fixation is considered appropriate multiple pinning should be used. Mobility after treatment was disappointing in about half of the patients, and we feel that internal fixation can only be justified in patients who are physiologically well preserved and who maintain a high level of activity.

  4. Long-term benefit perception, complications, and device malfunction rate of bone-anchored hearing aid implantation for profound unilateral sensorineural hearing loss.

    Science.gov (United States)

    Gluth, Michael B; Eager, Katrise M; Eikelboom, Robert H; Atlas, Marcus D

    2010-12-01

    To longitudinally evaluate short- and long-term subject satisfaction/benefit perception, device usage rates, complication rates, and external device repair rates of bone-anchored hearing aid (BAHA) implantation on a cohort of adult subjects with profound unilateral sensorineural hearing loss (PUSHL). Prospective clinical trial. Tertiary referral center. Fifty-six adults with PUSHL, 21 of which underwent BAHA implantation (followed for an average of 3.2 years after implantation; range, 0.8-4.6 yr). Short- and long-term satisfaction/benefit perception outcomes consisting of the Glasgow Hearing Aid Benefit Profile, Abbreviated Profile of Hearing Aid Benefit, and Single-Sided Deafness Questionnaire, including a comparison of results between implanted and nonimplanted subjects. Short- and long-term device usage rates, complications, and device failure issues also were carefully documented. There were statistically significant improvements in nearly all measures of benefit perception documented as well as a high rate of long-term device usage (81%). Although satisfaction and benefit perception outcomes generally tended to regress over time when compared with initial short-term outcomes, long-term scores still tended to be significantly improved nevertheless as compared with preoperative levels. Approximately 38% of implants experienced severe local skin reactions (Grade 2 and above) around the implant site at some point throughout the follow-up period, whereas only one (4.8%) required implant removal. 66.7% of subjects required repair of their external sound processor. BAHA implantation seems to provide a high level of short- and long-term perceived benefit and satisfaction in subjects with PUSHL and high rate of long-term device usage. Implant site adverse local skin reactions and repairs of the external sound processor were quite common.

  5. 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.

  6. 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

    OpenAIRE

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

    2015-01-01

    Abstract 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 meta...

  7. Closed External Fixation for Failing or Failed Femoral Shaft Plating in a Developing Country.

    Science.gov (United States)

    Aliakbar, Adil; Witwit, Ibrahim; Al-Algawy, Alaa A Hussein

    2017-08-01

    Femoral shaft fractures are one of the common injuries that is treated by open reduction, with internal fixation by plate and screws or intramedullary nailing, which can achieve a high union rate. To evaluate the outcome of using closed external fixation to augment a failing plate; with signs of screw loosening and increasing bone/plate gap; a failed plate; broken plate; screws completely out of bone with redisplacement of fracture. A retrospective study on 18 patients, aged between 17-42 years, who presented between 6-18 weeks after initial surgical fixation, with pain, difficulty in limb function, deformity and abnormal movement at fracture site, was done. X-Rays showed plating failure with acceptable amount of callus, which unfortunately had refractured. Cases associated with infection and no radiological evidence of callus formation were excluded from this study. Closed reduction was done by manipulation, then fracture fixation by AO external fixator. The patients were encouraged for full weight bearing as early as possible with dynamization later on. Of the 18 patients who underwent external fixation after close reduction, 15 cases showed bone healing in a period between 11-18 weeks (mean of 14.27 weeks) with good alignment (Radiologically). Removal of external fixator was done followed by physical therapy thereafter. Closed external fixation for treatment of failing or failed femoral plating, achieves good success rate and has less complications, is a short time procedure, especially in a hospital with limited resources.

  8. Umbilical Cord Wharton’s Jelly Repeated Culture System: A New Device and Method for Obtaining Abundant Mesenchymal Stem Cells for Bone Tissue Engineering

    Science.gov (United States)

    Xing, Junchao; Wu, Xuehui; Jin, Huiyong; Li, Zhiqiang; Deng, Moyuan; Xie, Zhao; Xu, Jianzhong

    2014-01-01

    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. PMID:25329501

  9. Cement technique for reducing post-operative bursitis after trochanteric fixation.

    Science.gov (United States)

    Derman, Peter B; Horneff, John G; Kamath, Atul F; Garino, Jonathan

    2013-02-01

    Post-operative trochanteric bursitis is a known complication secondary to the surgical approach in total hip arthroplasty. This phenomenon may be partially attributable to repetitive microtrauma generated when soft tissues rub against implanted hardware. Significant rates of post-operative trochanteric bursitis have been observed following procedures in which a trochanteric fixation device, such as a bolt-washer mechanism or a cable-grip/claw system, is used to secure the trochanteric fragment after trochanteric osteotomy. We present a simple technique for use with a bolt-washer system or grip plate in which trochanteric components are covered in bone wax followed by a layer of cement to decrease friction and to diminish the risk of post-operative bursitis.

  10. Biomechanical comparison of mono-segment transpedicular fixation with short-segment fixation for treatment of thoracolumbar fractures: a finite element analysis.

    Science.gov (United States)

    Xu, Guijun; Fu, Xin; Du, Changling; Ma, Jianxiong; Li, Zhijun; Tian, Peng; Zhang, Tao; Ma, Xinlong

    2014-10-01

    Mono-segment transpedicular fixation is a method for the treatment of certain types of thoracolumbar spinal fracture. Finite element models were constructed to evaluate the biomechanics of mono-segment transpedicular fixation of thoracolumbar fracture. Spinal motion (T10-L2) was scanned and used to establish the models. The superior half of the cortical bone of T12 was removed and the superior half of the cancellous bone of the T12 body was assigned the material properties of injured bone to mimic vertebral fracture. Transpedicular fixation of T11 and T12 was performed to produce a mono-segment fixation model; T11 and L1 were fixed to produce a short-segment fixation model. Motion differences between functional units and von Mises stress on the spine and implants were measured under axial compression, anterior bending, extensional bending, lateral bending and axial rotation. We found no significant difference between mono- and short-segment fixations in the motion of any functional unit. Stress on the T10/T11 nucleus pulposus and T10/T11 and L1/L2 annulus fibrosus increased significantly by about 75% on anterior bending, extensional bending and lateral bending. In the fracture model, stress was increased by 24% at the inferior endplate of T10 and by 43% at the superior endplate of L2. All increased stresses were reduced after fixation and lower stress was observed with mono-segment fixation. In summary, the biomechanics of mono-segment pedicle screw instrumentation was similar to that of conventional short-segment fixation. As a minimally invasive treatment, mono-segment fixation would be appropriate for the treatment of selected thoracolumbar spinal fractures. © IMechE 2014.

  11. Improving carbon fixation pathways.

    Science.gov (United States)

    Ducat, Daniel C; Silver, Pamela A

    2012-08-01

    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 and enhancing photosynthetic reactions in a species independent manner. Furthermore, the elucidation of alternative carbon-fixation routes distinct from the Calvin cycle raises possibilities that novel pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Brow lift fixation.

    Science.gov (United States)

    Gold, Alan H; Bernard, Robert W; Hamas, Robert S; McKinney, Peter; Paul, Malcolm D

    2003-05-01

    One of the more difficult and controversial aspects of forehead and brow lift is fixation with control and stabilization of the result. Aesthetic Surgery Journal has invited Robert W. Bernard, MD; Robert S. Hamas, MD; Peter McKinney, MD; and Malcolm D. Paul, MD to share their preferred brow lift techniques. Here are their responses to questions posed by "Comparing Notes" editor, Alan H. Gold, MD. (Aesthetic Surg J 2003;23:217-219.).

  13. 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...

  14. 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.

  15. Maxillomandibular Fixation by Plastic Surgeons: Cost Analysis and Utilization of Resources.

    Science.gov (United States)

    Farber, Scott J; Snyder-Warwick, Alison K; Skolnick, Gary B; Woo, Albert S; Patel, Kamlesh B

    2016-09-01

    Maxillomandibular fixation (MMF) can be performed using various techniques. Two common approaches used are arch bars and bone screws. Arch bars are the gold standard and inexpensive, but often require increased procedure time. Bone screws with wire fixation is a popular alternative, but more expensive than arch bars. The differences in costs of care, complications, and operative times between these 2 techniques are analyzed. A chart review was conducted on patients treated over the last 12 years at our institution. Forty-four patients with CPT code 21453 (closed reduction of mandible fracture with interdental fixation) with an isolated mandible fracture were used in our data collection. The operating room (OR) costs, procedure duration, and complications for these patients were analyzed. Operative times were significantly shorter for patients treated with bone screws (P < 0.002). The costs for one trip to the OR for either method of fixation did not show any significant differences (P < 0.840). More patients with arch bar fixation (62%) required a second trip to the OR for removal in comparison to those with screw fixation (31%) (P < 0.068). This additional trip to the OR added significant cost. There were no differences in patient complications between these 2 fixation techniques. The MMF with bone screws represents an attractive alternative to fixation with arch bars in appropriate scenarios. Screw fixation offers reduced costs, fewer trips to the OR, and decreased operative duration without a difference in complications. Cost savings were noted most significantly in a decreased need for secondary procedures in patients who were treated with MMF screws. Screw fixation offers potential for reducing the costs of care in treating patients with minimally displaced or favorable mandible fractures.

  16. Use of tightrope fixation in ankle syndesmotic injuries

    Directory of Open Access Journals (Sweden)

    Maempel Julian

    2014-02-01

    Full Text Available 【Abstract】Objective: Conventional fixation of syndesmotic injuries with screws remains problematic. A novel fibrewire device (Tightrope® 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 reduc- tion and time spent on non-weight bearing were recorded. Family doctors were contacted for those treated with Tight- ropes 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 of syndesmotic 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.

  17. Impact of external fixation on adolescents: an integrative research review.

    Science.gov (United States)

    Patterson, Miki

    2006-01-01

    To define the state of nursing knowledge about the psychological impact of treating adolescents with external fixation devices (EFDs). An integrated research review was conducted on literature available from CINAHL, MEDLINE, and PsycINFO. Keywords used were external fixation, fracture fixation, orthopaedic or orthopaedic, limb lengthening, Ilizarov, halo traction, Orthofix, EBI fixator, pelvic fixator, ring fixator, body image, self-concept, self-esteem, self-perception, adaptation, emotional, behavior, and outcome. Inclusion criteria for studies were (a) publication from 1990 to 2003, (b) focus on psychosocial and functional outcomes of treating adolescents with EFDs, and (c) publication in English. Studies were categorized by author, year, discipline(s), design, focus, sample, measurement, findings, and research recommendations. Findings and recommendations were compared across publications. All studies reported psychological and behavioral changes after EFD treatment. Pain and pin-site infections were the most problematic physical findings. Depression was universally evident to varying degrees, with some suicidal ideation and self-destructive behaviors, although mostly reported as transient. This predominantly retrospective cohort of studies reported social isolation as well as eating and sleep disturbances. Family and nursing support, a multiple disciplinary approach, and better preoperative preparation were crucial to adolescents psychological health after EFD treatment. Adolescents treated with EFDs require significant psychosocial support. The findings reveal major gaps in the knowledge on adolescents treated with external fixation for traumatic injury and none focused on EFD treatment in the acute period.

  18. Functional outcome following treatment of segmental skeletal defects of the forearm bones by Ilizarov application.

    Science.gov (United States)

    El-Mowafi, Hani; Elalfi, Barakat; Wasfi, Khaled

    2005-04-01

    Managing a segmental skeletal defect is a challenge, even more so if the combination of local infection with bone defect exacerbates the problem and provides an even more negative prognosis. Several techniques have been tried, among which skeletal allografts, autologous cortical or cancellous bone graft and vascularised bone graft, each with its limitation and success. In this study, we report our results with the Ilizarov method of bone transport to overcome bone defects of forearm bones due to infection. This series included 16 patients with bone defects of forearm bones, following either debridement of osteomylitis or infected nonunion. The mean time from injury to the Ilizarov procedure was 11.7 months. The mean number of operative procedures before application of the Ilizarov device was 3.4. The mean length of the defects after debridement was 6.4 cm. Monofocal osteotomy was performed. The mean external fixation index, distraction index and maturation index were 41.5 days/cm, 19.8 days/ cm, and 21.7 days/cm respectively. The mean time in the frame was 8.9 months. The mean total duration of treatment was 11.4 months. There were 14 complications in 11 patients including pin-track infection, premature consolidation, delayed union at the docking site and refracture. Ilizarov's technique of bone transport is an ideal solution for a large skeletal defect in spite of the high incidence of associated complications.

  19. Microwave-Assisted Tissue Preparation for Rapid Fixation, Decalcification, Antigen Retrieval, Cryosectioning, and Immunostaining

    Science.gov (United States)

    2016-01-01

    Microwave irradiation of tissue during fixation and subsequent histochemical staining procedures significantly reduces the time required for incubation in fixation and staining solutions. Minimizing the incubation time in fixative reduces disruption of tissue morphology, and reducing the incubation time in staining solution or antibody solution decreases nonspecific labeling. Reduction of incubation time in staining solution also decreases the level of background noise. Microwave-assisted tissue preparation is applicable for tissue fixation, decalcification of bone tissues, treatment of adipose tissues, antigen retrieval, and other special staining of tissues. Microwave-assisted tissue fixation and staining are useful tools for histological analyses. This review describes the protocols using microwave irradiation for several essential procedures in histochemical studies, and these techniques are applicable to other protocols for tissue fixation and immunostaining in the field of cell biology. PMID:27840640

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    investigated the influence of oral alendronate treatment on early implant fixation in two implant interface settings representing sites of an implant that are in contact with surrounding bone, and other sites without intimate bone contact. One plasma-sprayed cylindrical titanium implant (6 mm diameter...... of alendronate treatment. Bone ongrowth (bone in contact with implant surface) was estimated using the linear intercept technique and shear strength was calculated as the slope on a load-displacement curve. For the press fit implants, alendronate treatment significantly increased bone ongrowth from 24% to 29......Bone resorption associated with local trauma occurring during insertion of joint prostheses is recognized as an early event. Being an osteoclastic inhibitor, alendronate is a potential candidate means to decrease early periprosthetic bone resorption and thereby improve implant fixation. We...

  1. 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

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

    Science.gov (United States)

    Kayalar, Gulseren; Cevikol, Alev; Yavuzer, Gunes; Sanisoglu, Yavuz; Cakci, Aytul; Arasil, Tansu

    2009-01-01

    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). 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 energy X-ray laser measurements, all subjects were questioned about their medical history and the most relevant risk factors for osteoporosis. 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 (penergy 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 DXL and DXA Z-scores (r=0.33, p=0.001) at the femoral neck were statistically significant. Bone mineral density measurements in the calcaneus using a dual energy X-ray laser are valuable

  3. Absorbed doses by a technician, with and without (simulating) use of protection devices, in bone scintigraphy examination

    International Nuclear Information System (INIS)

    Jesus Lopes Filho, F. de; Antonio Filho, J.; Colaco, W.; Silveira, S.V. da

    1992-01-01

    The relation between the whole-body dose and the dose localized in body pants of a technician work in nuclear medicine was investigated by dosimetric films and thermoluminescent dosemeters. The investigation was made with and without a suitable protection devices. The results were discussed by a radiological protection view. (C.G.C.)

  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. Influence of sizes of abutments and fixation screws on dental implant system: a non-linear finite element analysis.

    Science.gov (United States)

    Mao, Zhihong; Yi, Dake; Cao, Guo

    2017-08-28

    The purpose of this study is to discuss the influence of sizes of abutments and fixation screws on immediately loaded dental implants in mandibular bones using nonlinear finite element methods. Abutments with three unilateral wall thicknesses and fixation screws with three diameters are analyzed to compare the stresses and deformations under a vertical or oblique force of 130 N. The nonlinearity due to friction contacts between the fixation screw, the abutment, the implant, and the bone is taken into account. The results showed that improper sizes of abutments and fixation screws would increase the stress and deformation of the dental implant system. If possible, the diameter of fixation screw should not be smaller than Φ1.0 mm, the diameter between Φ1.0 mm and Φ1.2 mm is acceptable. The fixation screw diameter preferably exceeds Φ1.4 mm. The unilateral wall thickness >0.5 mm is optimal selection for abutments.

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    Hiroshi Kobayashi

    2016-01-01

    Full Text Available 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.

  8. 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

  9. Nitrogen fixation apparatus

    Science.gov (United States)

    Chen, Hao-Lin

    1984-01-01

    A method and apparatus for achieving nitrogen fixation includes a volumetric electric discharge chamber. The volumetric discharge chamber provides an even distribution of an electron beam, and enables the chamber to be maintained at a controlled energy to pressure (E/p) ratio. An E/p ratio of from 5 to 15 kV/atm of O.sub.2 /cm promotes the formation of vibrationally excited N.sub.2. Atomic oxygen interacts with vibrationally excited N.sub.2 at a much quicker rate than unexcited N.sub.2, greatly improving the rate at which NO is formed.

  10. Clinical use of computed tomography and surface markers to assist internal fixation within the equine hoof.

    Science.gov (United States)

    Gasiorowski, Janik C; Richardson, Dean W

    2015-02-01

    To describe clinical use of computed tomography (CT) and hoof surface markers to facilitate internal fixation within the confines of the hoof wall. Retrospective case series. Horses (n = 16) that had CT-guided internal fixation of the distal phalanx (DP) or distal sesamoid bone (DSB). Drill bit entry point and direction were planned from CT image series performed on hooves with grids of barium paste dots at proposed entry and projected exit sites. Post-implantation CT images were obtained to check screw position and length as well as fracture reduction. Imaging, reduction, and surgical and general anesthesia times were evaluated. Outcome was recorded. Screw position and length were considered near optimal in all horses, with no consequential malposition of bits or screws. Fracture reduction was evident in all cases. Preoperative planning times (at least 2 CT image acquisitions and grid creation) ranged from 10 to 20 minutes. Surgery time ranged from 45 to 90 minutes (mean, 61 minutes) and general anesthesia time ranged from 115 to 220 minutes (mean, 171 minutes). The combination of CT and surface marker grids allowed accurate positioning of screws in clinical DP and DSB fractures. The technique was simple and rapid. An aiming device is useful for the technique. © Copyright 2014 by The American College of Veterinary Surgeons.

  11. Design and research of a new kind of minimally invasive fixation ...

    African Journals Online (AJOL)

    A new kind of external fixation for orthopaedics was designed in order to overcome the shortcomings of high weight, difficult operation and high degree of injury for the conventional external fixation. This device uses the so called quick casting method, which can be quickly concreted, to efficiently reduce the injury to patients.

  12. 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

  13. [Angle-stable fixation of intramedullary nails using the Angular Stable Locking System® (ASLS)].

    Science.gov (United States)

    Höntzsch, D; Blauth, M; Attal, R

    2011-12-01

    Greater stability in intramedullary osteosynthesis using angle-stable fixation with intramedullary nails and proximal locking screws. A novel screw-and-sleeve system (ASLS®, Synthes GmbH, Oberdorf, Switzerland) is applied using normal cannulated nails. Decisions can be made intraoperatively. This technology widens the range of indications for intramedullary nailing: The smaller and less stable the fragment requiring fixation, the greater the indication for angular stable fixation of the proximal and/or distal fragment. Femoral, tibial and humeral fractures, intramedullary osteosynthesis in osteoporotic bone and ante- and retrograde nailing. Particularly in the case of retrograde nailing, sustained prevention of nail toggling is achieved. None. Drill with the first drill bit, which has the same core diameter as the screw shaft. Drill the cortex to the external diameter of the sleeve. Place the sleeve on the tip of the screw. The screw-sleeve combination is then advanced through the larger near hole until the sleeve-covered screw tip sits in the locking hole of the intramedullary fixation nail. Advance the screw. As the screw diameter becomes larger, the sleeve expands resulting in an angular stable locking effect. The screw is then advanced until the head of the screw sits on the exposed surface of the cortex. The hole is filled with the expanded part of the screw shaft beneath the screw head. The necessary 1-3 turns are cut by the self-tapping flute on the screw. According to experience to date, this form of angle-stable fixation enables earlier and/or greater partial mobilization or earlier full mobilization. In all other respects, the guidelines for aftercare in intramedullary nailing apply. A multi-center pilot study has shown the technique to be reproducible and simple. There have been no complications using this technique to date. Biomechanical laboratory studies have demonstrated that stability with respect to axial and torsional loading is statically and

  14. Treatment of comminuted tibial shaft fractures in four dogs with the use of interlocking nail connected with type I external fixator.

    Science.gov (United States)

    Piórek, A; Adamiak, Z; Jaskólska, M; Zhalniarovich, Y

    2012-01-01

    The treatment of comminuted tibial shaft fractures in canine patients is burdened by significant risk which involves bone healing complications, such as delayed bone union. Complications may result from iatrogenic damage to blood vessels during fracture stabilization. To minimize this risk, treatment methods increasingly often rely on the concept of biological osteosynthesis. One of such methods involves the treatment of fractures with the use of new hybrid fixator consisted of an interlocking nail connected with type I external fixator. Connection of the nail with external fixator has been recently developed to maximize treatment efficiency. This manner of stabilization increases bone-fixator construct strength on forces acting in the place of fracture. It also enables fracture fixation with minimal damage of the blood supply of bone fragments. This article describes surgical procedure of stabilization of comminuted tibial bone fractures in four dogs by the use of interlocking nail connected with external fixator type I, discusses and evaluates the results of clinical treatment with the involvement of the said fixator. To control bone consolidation process the radiograms were taken in 6 and 8 week of healing. In all cases, the reviewed methods of clinical treatment were successful in producing bone union after eight week of healing. During the whole period of observations no complication was observed. In all cases the intramedullary nail were left in the medullary canal after the healing process was finished. The fixator supported quick restoration of limb function after treatment.

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

    Directory of Open Access Journals (Sweden)

    Venkata Gurava Reddy

    2011-01-01

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

  16. 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.

  17. 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 ...

  18. Clinical and radiological effect of medialized cortical bone trajectory for lumbar pedicle screw fixation in patients with degenerative lumbar spondylolisthesis: study protocol for a randomized controlled trial (mPACT).

    Science.gov (United States)

    Tschugg, Anja; Kavakebi, Pujan; Hartmann, Sebastian; Lener, Sara; Wipplinger, Christoph; Löscher, Wolfgang N; Neururer, Sabrina; Wildauer, Matthias; Thomé, Claudius

    2018-02-20

    Spinal fusion with pedicle screw fixation represents the gold standard for lumbar degenerative disc disease with instability. Although it is an established technique, it is nevertheless an invasive intervention with high complication rates. Therefore, minimally invasive approaches have been developed, the medialized bilateral screw pedicel fixation (mPACT) being one of them. The study objective is to evaluate prospectively the efficacy and safety of the mPACT technique compared with the traditional trajectory for degenerative lumbar spondylolisthesis. This is a single-center, randomized, controlled, parallel group, superiority trial. A total of 154 adult patients are allocated in a ratio of 1:1. Sample size and power calculation were performed to detect the minimal clinically important difference of 10%, with an expected standard deviation of 20% in the primary outcome parameter, the Oswestry Disability Index, with power of 80%, based on an assumed maximal dropout rate of 20%. Secondary outcome parameters include the EuroQoL 5-Dimension questionnaire, the Beck Depression Inventory, the painDETECT questionnaire and the "timed up and go" test. Furthermore, radiological and health economic outcomes will be evaluated. Follow up is performed until 5 years after surgery. Major inclusion criteria are lumbar degenerative spondylolisthesis with Meyerding grade I or II, which qualifies for decompression and fusion by medialised posterior screw placement with cortical trajectory (mPACT) or by a traditional trajectory for lumbar pedicle screw placement. This trial will contribute to the understanding of the short-term and long-term clinical and radiological postoperative course in patients with lumbar degenerative disc disease, in which the mPACT technique is used. ISRCTN registry, ISRCTN99263604 . Registered on 3 November 2016.

  19. Results of Lateral Condylar Blade Plate Fixation of Supracondylar ...

    African Journals Online (AJOL)

    Background: The concerns about operative stabilization of supracondylar femoral fractures are complications, especially hardware infection and disturbance of normal knee function. We reviewed the results of operative fixation of supracondylar femoral fractures using the lateral condylar blade plate device in our centre.

  20. Fixation Time for Evolutionary Graphs

    Science.gov (United States)

    Nie, Pu-Yan; Zhang, Pei-Ai

    Evolutionary graph theory (EGT) is recently proposed by Lieberman et al. in 2005. EGT is successful for explaining biological evolution and some social phenomena. It is extremely important to consider the time of fixation for EGT in many practical problems, including evolutionary theory and the evolution of cooperation. This study characterizes the time to asymptotically reach fixation.

  1. Complement fixation test to C burnetii

    Science.gov (United States)

    ... complement fixation test; Coxiella burnetii - complement fixation test; C burnetii - complement fixation test ... a specific foreign substance ( antigen ), in this case, C burnetii . Antibodies defend the body against bacteria, viruses, ...

  2. Axial loading cross screw fixation for the Austin bunionectomy.

    Science.gov (United States)

    Rigby, Ryan B; Fallat, Lawrence M; Kish, John P

    2011-01-01

    The Austin procedure has become a common method of osteotomy for the correction of hallux abductovalgus when indicated. The V-type configuration is intrinsically stable but not without complications. One complication encountered is rotation and/or displacement of the capital fragment. We present the use of an axial loading screw in conjunction with a dorsally placed compression screw. The benefit to this technique lies in the orientation of the axial loading screw, because it is directed to resist the ground reactive forces while also providing a second point of fixation in a crossing screw design. In a head-to-head biomechanical comparison, we tested single dorsal screw fixation versus double screw fixation, including both the dorsal and the axial loading screws in 10 metatarsal Sawbones(®) (Pacific Research Laboratories Inc, Vashon, WA). Five metatarsals received single dorsal screw fixation and five received the dorsal screw and the additional axial loading screw. The metatarsals were analyzed on an Instron compression device for comparison; 100% of the single screw fixation osteotomies failed with compression at an average peak load of 205 N. Four of five axial loading double screw fixation osteotomies did not fail. This finding suggests that the addition of an axial loading screw providing cross screw orientation significantly increases the stability of the Austin osteotomy, ultimately decreasing the likelihood of displacement encountered in the surgical repair of hallux abductovalgus. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  3. 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.

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

    Science.gov (United States)

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

    2015-01-01

    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. 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. 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). 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.

  5. Comparison of three fixations for tibial plateau fractures by biomechanical study and radiographic observation.

    Science.gov (United States)

    Chen, Hong-wei; Liu, Guo-dong; Ou, Shan; Jiang, Xie-yuan; Fei, Jun; Wu, Li-jun

    2015-01-01

    The aim of this study was to compare the fixation effects of three fixation devices for tibial plateau fracture (AO/OTA classification 41 A1). Sixteen human cadaver tibial specimens were randomly divided into four groups. An A1 fracture model was established. The fractures were subsequently fixed by axial controlled intramedullary nail, external fixation and steel plate fixation. Each specimen was subjected to axial compression, torsion test and three-point bending test. Then a rat model was used to evaluate the therapeutic effect of these three fixations by evaluation of callus formation time and healing time. It was found that the axial controlled intramedullary nail group obtained superior biomechanical properties of resistance ability of bending, torsional and axial compressive, compared with external fixation and steel plate group. In animal experiments, the axial controlled intramedullary nail group had a significant shorter callus occurrence and healing time than steel plate and external fixator group. The axial controlled intramedullary nail fixation has a superior biomechanical characteristic and fixation effect for tibial plateau fractures than steel plate and external fixator. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  6. Pediatric stapedectomy: does cause of fixation affect outcomes?

    Science.gov (United States)

    Neilan, Ryan E; Zhang, Richard W; Roland, Peter S; Isaacson, Brandon; Lee, Kenneth H; Walter Kutz, J

    2013-07-01

    To compare outcomes of stapedectomy in patients with congenital stapes fixation versus juvenile otosclerosis. A retrospective chart review was performed from January 1, 1999 until January 1, 2011 to identify patients under 18 years old who underwent a stapedectomy. Age, gender, pre- and postoperative audiograms, intraoperative findings including etiology of stapes fixation, prosthesis type, and complications were recorded. Twenty-two children were identified who had undergone a stapedectomy (two patients underwent sequential bilateral surgery) resulting in a total of 24 ears. The cause of fixation included juvenile otosclerosis (n=7) and congenital stapes fixation (n=17). The overall mean pre-operative air-bone gap (ABG) was 34.7 dB (SD: 13.5) compared to a postoperative mean ABG of 9.0 (SD: 9.3) (pdiscrimination score of 80%. Pediatric stapedectomy has comparable results to stapedectomy in adults regardless of the cause of stapes fixation; however, delayed sensorineural hearing loss may be higher in the pediatric population. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Results of deformity correction in children with X-linked hereditary hypophosphatemic rickets by external fixation or combined technique.

    Science.gov (United States)

    Popkov, Arnold; Aranovich, Anna; Popkov, Dmitry

    2015-12-01

    The operative procedures to correct multiplanar bone deformities may be indicated for prevention of secondary orthopaedic complications in children with X-linked hereditary hypophosphatemic rickets (XHPR). Different problems related to surgical correction were reported: increased rate of non-union, delayed union, recurrent deformity, deep intramedullary infection, refracture, nerve palsy, and pin tract infection. The aim of this retrospective study was comparison of results of correction in children with XHPR who underwent the treatment with either the Ilizarov device alone or a combined technique: the Ilizarov fixator with flexible intramedullary nailing (FIN) with hydroxyapatite bioactive coating and FIN. We retrospectively analysed 47 cases (children of age under 14 years) affected by XHPR. Simultaneous deformity correction in femur and tibia was performed with the Ilizarov device (group I) or the combined method (group II). This article is based on the results of a historical comparative retrospective study from the same institution. The duration of external fixation is noted to be shorter applying the combined technique: 124.7 days (group I) vs 87.4 days (group II). In both groups deformity correction was achieved with a proper alignment. Nevertheless, while a child continues to grow during long-term follow-up, deviations of the mechanic axis from the centre of the knee joint have been developing again and values of mLDFA, mMPTA have become pathologic in the most of the cases. In group I location of a newly developed deformity resembled a pre-operative one, whereby both diaphyseal and metaphyseal parts were deformed. In group II in all the cases an apex of deformity was located in distal metadiaphyseal zone of the femur and proximal metadiaphyseal zone of the tibia. It is important to note that all of those in group II were out of the zone of the intramedullary nail. Simultaneous correction of femoral and tibial deformities by means of circular external

  8. 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.

  9. To fix or not to fix? The role of fibular fixation in distal shaft fractures of the leg.

    Science.gov (United States)

    Berlusconi, M; Busnelli, L; Chiodini, F; Portinaro, N

    2014-02-01

    The role of stabilisation of the fibula in distal two-bone fractures of the leg is controversial. Some studies indicate the need for fibular stabilisation in 43 AO fractures, but few studies consider the role of the fibula in 42 AO fractures. The aim of the current paper is to explain the role of stabilisation of the fibula in 42 AO fractures, correlating the rates of healing and non-union between patients with and without fibula fixation. A total of 60 patients with 42 AO (distal) shaft fracture of the tibia with associated fracture of the fibula were selected. Patients were divided into two groups according to whether or not the fibula was fixed: Group I (n=26) comprised patients who had their fibula fixed while Group II (n=34) comprised patients who did not. The fibular fracture was classified according to the AO and related to the level of the tibial fracture. Other parameters examined were the union rate of the two groups correlated to the fracture pattern and position of the fibular fracture; the demographic data, such as age and gender; the presence of an open fracture, and the type of tibial fixation device used (nail or plate). None of the parameters considered (open injury, AO classification, device used and level of the fibular fracture relative to the tibial) were shown to have an influence on the development of a non-union. This study showed a higher non-union rate when the fracture of the tibia and fibula were at the same level, the tibia was fixed with a bridging plate and the fibula left untouched. For this reason, we recommend fibular fixation in all 42 distal fractures when both fractures lie on the same plane and the tibial fracture is relatively stabilised. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Impact of Biomechanical Forces on Antibiotics Release Kinetics from Hydroxyapatite Coated Surgical Fixation Pins

    OpenAIRE

    Lilja, Mirjam; Sörensen, Jan Henrik; Sörensen, Torben; Åstrand, Maria; Procter, Philip; Steckel, Hartwig; Strømme, Maria

    2013-01-01

    This work investigates the impact of biomechanical wear and abrasion on the antibiotic release profiles of hydroxyapa-tite (HA) coated fixation pins during their insertion into synthetic bone. Stainless steel fixation pins are coated with crystalline TiO2 by cathodic arc evaporation forming the bioactive layer for biomimetic deposition of Tobramycin con-taining HA. Tobramycin is either introduced by co-precipitation during HA formation or by adsorption-loading after HA deposition. The samples...

  11. Management of open fractures using a noncontact locking plate as an internal fixator

    Directory of Open Access Journals (Sweden)

    Azad Yildirim

    2017-01-01

    Conclusions: This case series demonstrates that an “internal fixator technique” is an acceptable alternative to the management of open fractures of the femur or tibia in adult patients. The NC-LP method provided opportunities to achieve a stable fixation with noncontact between the implant and the bone tissues, and the fractures were sufficiently stabilized to allow union with a low complication rate.

  12. Fixation of an Anatomically Designed Cementless Stem in Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Shigeru Nakamura

    2012-01-01

    Full Text Available Purpose. The Anatomic Fiber Metal plus stem (Zimmer is one of the anatomically designed cementless stems to achieve stable fixation by metaphyseal fit. We studied outcomes of cementless total hip arthroplasty using this stem and possible effects of metaphyseal fit on outcomes. Methods. The cementless total hip arthroplasty using this stem was performed for 155 hips. One hundred and thirty-seven hips of 122 patients were followed for 5 to 16 (mean, 9.7 years and entered into the study. The metaphyseal fit was defined as good or poor in an anteroposterior radiograph after surgery. We studied the fixation of the stem and bone reaction on an anteroposterior radiograph at the final followup. Results. Twelve hips had revision, six acetabular components and six acetabular liners. No stem was revised. The biological fixation of the stem was bone ingrown fixation for 136 hips and unstable for one. The metaphyseal fit was good for 83 hips and poor for 54 hips. There were no differences for stem fixation and bone reaction between the two groups. Conclusions. The fixation of the stem was stable at a mean followup of 9.7 years independently from metaphyseal fit.

  13. Tapered modular fluted titanium stems for femoral fixation in revision total knee arthroplasty.

    Science.gov (United States)

    Stambough, Jeffrey B; Mason, J Bohannon; Riesgo, Aldo M; Fehring, Thomas K

    2018-03-01

    Consensus regarding femoral stem fixation options in revision total knee arthroplasty remains controversial. Tapered, modular, fluted titanium (TMFT) stems have an excellent track record in total hip arthroplasty for their ability to provide axial and rotational stability in situations of compromised host bone. We present 3 successfully treated cases in which the Food & Drug Administration granted permission to use custom TMFT stems in situations of failed femoral fixation in multiple revised knees. These stems hold promise to achieve stable fixation in revision total knee arthroplasty where host metadiaphyseal bone is deficient. Implant manufactures should consider dedicating future resources to create adapters that can link existing successful TMFT stems currently used in hip arthroplasty to revision total knee components when host bone is severely compromised.

  14. Primary stability of three different iliosacral screw fixation techniques in osteoporotic cadaver specimens-a biomechanical investigation.

    Science.gov (United States)

    Oberkircher, Ludwig; Masaeli, Adrian; Bliemel, Christopher; Debus, Florian; Ruchholtz, Steffen; Krüger, Antonio

    2016-02-01

    The incidence of osteoporotic and insufficiency fractures of the pelvic ring is increasing. Closed reduction and percutaneous fixation with cannulated sacroiliac screws is well-established in the operative treatment of osteoporotic posterior pelvic ring fractures. However, osteoporotic bone quality might lead to the risk of screw loosening. For this reason, cement augmentation of the iliosacral screws is more frequently performed and recommended. The aim of the present biomechanical study was to evaluate the primary stability of three methods of iliosacral screw fixation in human osteoporotic sacrum specimens. This study used methodical cadaver study. A total of 15 fresh frozen human cadaveric specimens with osteoporosis were used (os sacrum). After matched pair randomization regarding bone quality (T-score), three operation technique groups were generated: screw fixation (cannulated screws) without cement augmentation (Group A); screw fixation with cement augmentation before screw placement (cannulated screws) (Group B); and screw fixation with perforated screws and cement augmentation after screw placement (Group C). In all specimens both sides of the os sacrum were used for operative treatment, resulting in a group size of 10 specimens per group. One operation technique was used on each side of the sacral bone to compare biomechanical properties in the same bone quality. Pull-out tests were performed with a rate of 6 mm/min. A load versus displacement curve was generated. Subgroup 1 (Group A vs. Group B): Screw fixation without cement augmentation: 594.4 N±463.7 and screw fixation with cement augmentation before screw placement: 1,020.8 N±333.3; values were significantly different (p=.025). Subgroup 2 (Group A vs. Group C): Screw fixation without cement augmentation: 641.8 N±242.0 and perforated screw fixation with cement augmentation after screw placement: 1,029.6 N±326.5; values were significantly different (p=.048). Subgroup 3 (Group B vs. Group C): Screw

  15. Management of Bone Gaps with Intramedullary Autologous Fibular ...

    African Journals Online (AJOL)

    ... 7 consecutive patients who presented with bone gaps that were managed with intramedullary non vascularised fibular strut graft. Method: Intramedulary Autologous fibular strut graft was used to breach the bone and the whole length augmented with cancellous graft and bridged with bone plate; external fixators or k wires.

  16. Determinants of Patronage of Traditional Bone Setters in the Middle ...

    African Journals Online (AJOL)

    A fixated cultural outlook was recognized as being the motivating factor for patronage of traditional bone setters. Need for enlightenment campaign of the public against patronage of traditional bone setters is emphasized. A gradual phasing out of traditional bone setting with a road map towards making orthodox fracture ...

  17. A new treatment for avulsion fracture of the calcaneus using an Ilizarov external fixator.

    Science.gov (United States)

    Takahashi, Masayasu; Noda, Mitsuaki; Saegusa, Yasuhiro

    2013-11-01

    In the treatment of avulsion fractures of the posterior calcaneal tuberosity, open reduction and internal fixation are prone to several complications. We describe a new treatment using an Ilizarov external fixator, which can minimise the complications and achieve sufficient stability of the displaced fragment. A 55-year-old woman sustained an avulsion fracture of the calcaneus. Examination revealed the development of bruising with extremely taut skin over the posterior prominence of the displaced bone. Radiographs demonstrated grossly proximal displacement of the tuberosity fragment. Surgery was exclusively percutaneous using an Ilizarov external fixator. The displaced fragment was adequately reduced and stabilised. Progressive weight bearing in the equinus position was initiated at the third week after surgery and the external fixator was removed at the seventh week. There was no skin necrosis or loss of reduction while the fixator was maintained. Postoperative follow-up for 2 years revealed full recovery. Major postoperative complications after conventional open reduction and internal fixation include skin necrosis, skin irritation by metal implants and re-displacement of the reduced fragment. Our method of using an external fixator may decrease the incidence of these three complications. Skin incision and the risk of skin necrosis are inevitable during internal fixation. On the other hand, the use of an external fixator reduces or eliminates skin necrosis, as it is applied percutaneously for reduction and stabilisation of the fragment. External fixation is mostly recommended in cases of poor vascularity or bruising. In addition, skin irritation can be avoided upon removal of the external fixator. Re-displacement occurs occasionally as a serious complication in lag screw fixation, particularly in cases with poor purchase of the osteoporotic bone. Tension band wiring and application of an Ilizarov external fixator in avulsion fractures of the calcaneus can

  18. Biomechanical effect of interspinous process distraction height after lumbar fixation surgery: An in vitro model.

    Science.gov (United States)

    Fu, Lin; Ma, Jianxiong; Lu, Bin; Jia, Haobo; Zhao, Jie; Kuang, Mingjie; Feng, Rui; Xu, Liyan; Bai, Haohao; Sun, Lei; Wang, Ying; Ma, Xinlong

    2017-07-01

    Pedicle screw fixation may induce abnormal activity at adjacent segment and accelerate the degeneration of lumbar vertebrae. Dynamic stabilizers could provide an intermediate solution between conservative treatment and fusion surgery. Lumbar vertebral segment cephalad to instrumented fixation was the most common localization of adjacent segment degeneration. The aim of this study is to explore the use of interspinous process devices in the lumbar vertebral segment cephalad to fixation segment in changing the mechanical distribution and limiting abnormal activity of the spine. Eight specimens were tested in the following groups: intact group, instability group (bilateral facetectomy at L3-L4), fixation group (bilateral facetectomy and pedicle screw fixation at L3-L4), and hybrid fixation group (fixation at L3-L4 and simulating interspinous device implantation of 6, 8, 10, 12, 14, 16, and 18 mm at L2-L3). Range of motion, motion of vertebral body, and strain distribution change were recorded. The range of motion in extension with 16- and 18-mm hybrid constructs was significantly lower than intact, instability, and fixation groups. In flexion and lateral bending, the strain values of L4 inferior articular process with 18-mm hybrid construct have a significant difference compared with other groups. In axial rotation, under the condition of a contralateral state, the strain values of L2 superior articular process with 18-mm hybrid construct have a significant difference compared with intact and fixation groups. The strain value of the L4 inferior articular process had negative correlation with height distraction in three dimensions, except extension. A negative correlation between the strain value of the L2 superior articular process and distraction height was found in contralateral bending and contralateral axial rotation. Interspinous process devices above the fixation segment can change the mechanical distribution of the spine and limit activity in some of the

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

    Directory of Open Access Journals (Sweden)

    Qiang He

    bone cement for prosthetic fixation in total joint replacement.

  20. 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.

  1. Preliminary biomechanical study of different acetabular reinforcement devices for acetabular reconstruction.

    Directory of Open Access Journals (Sweden)

    Ching-Lung Tai

    Full Text Available Acetabular reinforcement devices (ARDs are frequently used as load-sharing devices to allow allograft incorporation in revision hip arthroplasty with massive acetabular bone loss. The key to a successful reconstruction is robust fixation of the device to the host acetabulum. Interlocking fixation is expected to improve the initial stability of the postoperative construct. However, all commercially available ARDs are designed with non-locking fixation. This study investigates the efficacy of standard ARDs modified with locking screw mechanisms for improving stability in acetabular reconstruction.Three types of ARDs were examined to evaluate the postoperative compression and angular stability: i standard commercial ARDs, ii standard ARDs modified with monoaxial and iii standard ARDs modified with polyaxial locking screw mechanisms. All ARDs were implanted into osteomized synthetic pelvis with pelvic discontinuity. Axial compression and torsion tests were then performed using a servohydraulic material testing machine that measured load (angle versus displacement (torque. Initial stability was compared among the groups.Equipping ARDs with interlocking mechanisms effectively improved the initial stability at the device/bone interface compared to standard non-locked ARDs. In both compression and torsion experiments, the monoaxial interlocking construct demonstrated the highest construct stiffness (672.6 ± 84.1 N/mm in compression and 13.3 ± 1.0 N · m/degree in torsion, whereas the non-locked construct had the lowest construct stiffness (381.4 ± 117.2 N/mm in compression and 6.9 ± 2.1 N · m/degree in torsion (P < 0.05.Our study demonstrates the potential benefit of adding a locking mechanism to an ARD. Polyaxial ARDs provide the surgeon with more flexibility in placing the screws at the cost of reduced mechanical performance. This in vitro study provides a preliminary evaluation of biomechanical performance for ARDs with or without interlocking

  2. 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.

  3. 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

  4. Biomechanical Comparison of Intramedullary Screw Versus Low-Profile Plate Fixation of a Jones Fracture.

    Science.gov (United States)

    Huh, Jeannie; Glisson, Richard R; Matsumoto, Takumi; Easley, Mark E

    2016-04-01

    Intramedullary screw fixation of fifth metatarsal Jones fractures often produces satisfactory results, however, nonunion and refracture rates are not negligible. The low-profile "hook" plate is an alternative fixation method that has been promoted to offer improved rotational control at the fracture site, but this remains to be proven. The purpose of this study was to document biomechanical performance differences between this type of plate and a contemporary solid, dual-pitch intramedullary screw in a cadaveric Jones fracture model. Simulated Jones fractures were created in 8 matched pairs of fresh-frozen cadaveric fifth metatarsals. One bone from each pair was stabilized using an intramedullary TriMed Jones Screw and the other using a TriMed Jones Fracture Plate (TriMed, Inc, Santa Clarita, CA). Controlled bending and torsional loads were applied. Bending stiffness and fracture site angulation, as well as torsional stiffness, peak torque, and fracture site rotation were quantified and compared. Intramedullary screw fixation demonstrated greater bending stiffness and less fracture site angulation than plate fixation during plantar-to-dorsal and lateral-to-medial bending. Torsional stiffness of screw-fixed metatarsals exceeded that of plate-fixed bones at initial loading; however, as rotation progressed, the plate resisted torque better than the screw. No difference in peak torque was demonstrable between fixation methods, but it was reached earlier in specimens fixed with screws and later in those fixed with plates as rotation progressed. In this cadaveric Jones fracture model, intramedullary screw fixation demonstrated bending stiffness and resistance to early torsional loading that was superior to that offered by plate fixation. Although low-profile "hook" plates offer an alternative for fixation of fifth metatarsal Jones fractures, intramedullary screw fixation may provide better resistance to bending and initiation of fracture site rotation. The influence of

  5. Contribution of monaural and binaural cues to sound localization in listeners with acquired unilateral conductive hearing loss: improved directional hearing with a bone-conduction device.

    Science.gov (United States)

    Agterberg, Martijn J H; Snik, Ad F M; Hol, Myrthe K S; Van Wanrooij, Marc M; Van Opstal, A John

    2012-04-01

    Sound localization in the horizontal (azimuth) plane relies mainly on interaural time differences (ITDs) and interaural level differences (ILDs). Both are distorted in listeners with acquired unilateral conductive hearing loss (UCHL), reducing their ability to localize sound. Several studies demonstrated that UCHL listeners had some ability to localize sound in azimuth. To test whether listeners with acquired UCHL use strongly perturbed binaural difference cues, we measured localization while they listened with a sound-attenuating earmuff over their impaired ear. We also tested the potential use of monaural pinna-induced spectral-shape cues for localization in azimuth and elevation, by filling the cavities of the pinna of their better-hearing ear with a mould. These conditions were tested while a bone-conduction device (BCD), fitted to all UCHL listeners in order to provide hearing from the impaired side, was turned off. We varied stimulus presentation levels to investigate whether UCHL listeners were using sound level as an azimuth cue. Furthermore, we examined whether horizontal sound-localization abilities improved when listeners used their BCD. Ten control listeners without hearing loss demonstrated a significant decrease in their localization abilities when they listened with a monaural plug and muff. In 4/13 UCHL listeners we observed good horizontal localization of 65 dB SPL broadband noises with their BCD turned off. Localization was strongly impaired when the impaired ear was covered with the muff. The mould in the good ear of listeners with UCHL deteriorated the localization of broadband sounds presented at 45 dB SPL. This demonstrates that they used pinna cues to localize sounds presented at low levels. Our data demonstrate that UCHL listeners have learned to adapt their localization strategies under a wide variety of hearing conditions and that sound-localization abilities improved with their BCD turned on.

  6. [Complex reconstruction with internal locking plate fixation for Charcot arthropathy].

    Science.gov (United States)

    Ramadani, F; Härägus, H; Radu, P; Trieb, K; Hofstaetter, S

    2015-01-01

    Osteosynthesis and reposition of the Charcot foot is challenging with respect to choice of a proper implant. There is currently no international consensus regarding the optimal implant. Locking plates seem to be an innovative and stable method for reconstruction. The aim of this work is to analyze bone fusion, complications, pseudoarthrosis, and patient satisfaction. This paper presents a retrospective analysis of 63 consecutive Charcot feet treated between 2004 and 2014. The mean follow-up time was 2.4 years. All Charcot feet treated between 2004 and 2014 were Sanders type II or III. A bony fusion was achieved in 50 % of the cases, 26 % had a functional pseudoarthrosis with intact implants and pain-free mobility, and 22 % showed no healing with broken implants. Conclusion Internal fixation with locking plates is superior to screw fixation only with regard to biomechanics. We prefer internal fixation plates to external fixation because of stability even in the case of pseudoathrosis and because of the learning curve.

  7. Comparison of internal fixation techniques in metacarpal fractures.

    Science.gov (United States)

    Black, D; Mann, R J; Constine, R; Daniels, A U

    1985-07-01

    A biomechanical study assessed quantitative differences in the stability that was obtained by five commonly used types of internal fixation employed in metacarpal fractures. The techniques included dorsal plating, dorsal plating combined with an interfragmentary lag screw, crossed Kirschner wires, a single intraosseous wire combined with a single oblique Kirschner wire, and a single intraosseous wire alone. Rigidity and strength in torsion and bending were determined after transverse osteotomy and fixation of the metacarpal were performed. The failure modes for each fixation technique were also observed and described. Significant differences in rigidity were found between the plated configurations (with or without an interfragmentary lag screw) and the wired configurations in both apex dorsal bending and axial torsion. The three wired configurations were not significantly different from each other except in torsion. Analysis of the bending moments that were required to produce both yield and failure in apex dorsal bending and also the energy absorbed to yield showed similar disparity between plated and wired techniques. For metacarpal fixation, dorsal plating with or without lag screws provides significantly more stability than do wired techniques and approaches that provided by intact bones.

  8. The anterior subcutaneous internal fixator (ASIF) for unstable pelvic ring fractures: clinical and radiological mid-term results.

    Science.gov (United States)

    Müller, Franz Josef; Stosiek, Wolfgang; Zellner, Michael; Neugebauer, Rainer; Füchtmeier, Bernd

    2013-11-01

    The purpose of this study was to determine the outcome of unstable type C pelvic fractures treated with posterior stabilisation and the anterior subcutaneous internal fixator (ASIF). Altogether, 36 consecutive patients were treated for unstable type C pelvic ring fractures using posterior stabilisation and ASIF. After a minimum of 18 months, the clinical and radiological outcome was retrospectively investigated. Overall, three patients (8.3%) died, and 31 patients (86%) were available for follow-up after a mean of 4.5 years. Thirty of 31 patients (97%) showed radiographic bone consolidation of both the posterior and anterior pelvic ring. Only one non-union and two infections due to the anterior device were observed. The total German pelvic outcome score showed an excellent or good rating for 64.5% of the patients, and a fair or poor for 35.5%. The SF-12 questionnaire showed a significantly reduced total score for physical and mental health compared to a general reference population. The ASIF represents an innovative surgical procedure for the treatment of type C pelvic ring fractures. In the medium term, patient satisfaction was high and the complication rate was low, despite the small number of patients. More cases must be investigated before the procedure can be recommended in general, possibly replacing the external fixator for the treatment of pelvic ring fractures in the future.

  9. In situ comparison of varying composite tibial tunnel interference screws used for ACL soft tissue graft fixation.

    Science.gov (United States)

    Nyland, John; Krupp, Ryan; Greene, Joe; Bowles, Richard; Burden, Robert; Caborn, David N M

    2015-12-01

    This mechanical study using an in vitro porcine model compared composite interference screw fixation of soft tissue ACL grafts in tibial tunnels. Forty-eight porcine profundus tendons and tibiae were divided into four groups of 12 closely matched specimens. Equivalent diameter grafts were assigned to each group. Tibial bone tunnels were drilled to 0.5mm greater than graft diameter. Grafts were fixed in tunnels using one 10 × 35 mm composite interference screw designed by four different manufacturers. Maximal insertion torque and perceived within group mechanical testing outcome predictions were recorded. Constructs were potted and loaded into a six degrees of freedom clamp that placed the servohydraulic device tensile loading vector in direct tunnel alignment. Constructs were pre-loaded to 25 N, pre-conditioned between 0 and 50 N for 10 cycles (0.5 Hz), submaximally tested between 50 and 250 N for 500 cycles (one hertz) and load to failure tested at 20mm/min. Statistically significant differences were not observed between groups for displacement during submaximal cyclic loading, yield load, displacement at yield load, stiffness, ultimate load at failure and displacement at ultimate load. One composite screw group displayed a slightly greater proportion of specimens that required use of more than one screw during insertion. Under highly controlled conditions groups displayed comparable fixation. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. A comparison of two fixation methods for femoral trochanteric fractures: a new generation intramedullary system vs sliding hip screw.

    Science.gov (United States)

    Carulli, Christian; Piacentini, Federico; Paoli, Tommaso; Civinini, Roberto; Innocenti, Massimo

    2017-01-01

    Trochanteric fractures are frequent and generally associated with bone fragility. There is still debate on the best fixation device to treat stable or rather stable trochanteric fractures: we report our clinical and radiological results of fixation with Proximal Femoral Nail "antirotation" (PFNa) in a population of patients compared to a control group treated by Sliding Hip Screw (SHS). A prospective study was conducted in 71 consecutive patients treated by PFNa (group A), and 69 by a SHS (group B), with a mean age of 81.6 and 83.4 years respectively. Short Form 12 was administered to check postoperative results, and the following parameters were evaluated: range of motion, evaluation of pain, gait ability, X-rays, and Tip Apex Distance Index. A minimum follow-up was conducted in 128 patients: 66 subjects belonging to the PFNa group and 62 to the DHS group. All patients in the group A were able to reach partial or full weight-bearing on the operated leg before leaving the hospital. Forty-four patients (63.8%) of the group B were able to walk with partial weight-bearing before discharge. We recorded 17 complications with a final overall percentage of 17.2% on the overall study population with one single case of failure in both the two groups. A statistical significance (ptrochanteric fractures as well as DHS. The light superiority of PFNa may be principally related to its mechanical advantages.

  11. Screw Versus Plate Fixation for Chevron Osteotomy: A Retrospective Study.

    Science.gov (United States)

    Andrews, Boyd J; Fallat, Lawrence M; Kish, John P

    2016-01-01

    The chevron osteotomy is a popular procedure used for the correction of moderate hallux abducto valgus deformity. Fixation is typically accomplished with Kirschner wires or bone screws; however, in cystic or osteoporotic bone, these could be inadequate, resulting in displacement of the capital fragment. We propose using a locking plate and interfragmental screw for fixation of the chevron osteotomy that could reduce the healing time and decrease the incidence of displacement. We performed a retrospective cohort study for chevron osteotomies on 75 feet (73 patients). The control groups underwent fixation with 1 screw in 30 feet (40%) and 2 screws in 30 feet (40%). A total of 15 feet (20%) were included in the locking plate and interfragmental screw group. The patients were followed up until bone healing was achieved at a median of 7 (range 6 to 14) weeks. Our hypothesis was that those treated with the locking plate and interfragmental screw would have a faster healing time and fewer incidents of capital fragment displacement compared with the 1- or 2-screw groups. The corresponding mean intervals to healing for the 1-screw group was 7.71 ± 1.28 (range 6 to 10) weeks, for the 2-screw group was 7.27 ± 1.57 (range 6 to 14) weeks, and for the locking plate and interfragmental screw group was 7.01 ± 1.00 (range 6 to 9) weeks. One case of capital fragment displacement occurred in the single screw group and one in the 2-screw group. No displacement occurred in the locking plate and interfragmental screw group. Neither finding was statistically significant. However, we believe the locking plate and interfragmental screw could be a viable option in patients with osteoporotic and cystic bone changes for correction of hallux abducto valgus. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Bone Diseases

    Science.gov (United States)

    ... avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... break Osteogenesis imperfecta makes your bones brittle Paget's disease of bone makes them weak Bones can also ...

  13. [Plate fixation and open wound treatment in infected intramedullar nails].

    Science.gov (United States)

    Lusser, G M; Müller, J

    1978-12-01

    In treating patients who present with an extensive non-union due to infected intramedullary nail, bone healing can be achieved within a few weeks through a policy of active management. Following excision of the infected tissue and thorough irrigation, the fracture site is stabilized by a plate fixation and a packet with cancellous bone. The wound overlying the bone is left open to granulate. No complications were observed during the course of healing in 7 cases (5 tibia, 2 femur) managed this way. The method is based on classical principles of orthopedics and the treatment of infection. Such has been its impressive success, that it would seem to warrant not only close attention but also strong recommendation.

  14. Distal fibula fracture fixation: Biomechanical evaluation of three different fixation implants.

    Science.gov (United States)

    Knutsen, Ashleen R; Sangiorgio, Sophia N; Liu, Chang; Zhou, Steve; Warganich, Tibor; Fleming, John; Harris, Thomas G; Ebramzadeh, Edward

    2016-12-01

    The goal of this study was to evaluate the biomechanical performance of three distal fibula fracture fixation implants in a matched pair cadaveric fibula model: (1) a 5-hole compression plate with lag screw, (2) a 5-hole locking plate with lag screw, and (3) the 6-hole tabbed-plate with locking screws. Three-dimensional motions between the proximal and distal fibular segments were measured under cyclic valgus bending, cyclic compressive axial loading, and cyclic torsional external-rotation loading. During loading, strains were measured on the surfaces of each fibula near the simulated fracture site, and on the plate, to assess load transfer. Bone quality was quantified globally for each donor using bone mineral density (BMD) measured using Dual X-ray absorptiometry (DEXA) and locally at the fracture site using bone mineral content (BMC) measured using peripheral quantitative computed tomography (pQCT). Mean failure loads were below 0.2Nm of valgus bending and below 4Nm of external-rotational torque. Mean failure angulation was below 1degree for valgus bending, and failure rotation was below 7degrees for external-rotation. In the compression plate group, significant correlations were observed between bone quality (global BMD and local BMC) and strain in every one of the five locations (Pearson correlation coefficients >0.95, p<0.05). In contrast, in the locking and tabbed-plate groups, BMD and BMC correlated with far fewer strain locations. Overall, the tabbed-plate had similar construct stability and strength to the compression and locking plates. However, the distribution of load with the locking and tabbed-plates was not as heavily dependent on bone quality. Copyright © 2016 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  15. All-Suture Transosseous Repair for Rotator Cuff Tear Fixation Using Medial Calcar Fixation

    Science.gov (United States)

    Aramberri-Gutiérrez, Mikel; Martínez-Menduiña, Amaia; Valencia-Mora, María; Boyle, Simon

    2015-01-01

    We describe an all-suture transosseous repair technique used in the management of rotator cuff tears by means of an all-suture anchor secured on the intra-articular side of the humeral calcar. The technique uses an anterior cruciate ligament guide to ensure accurate positioning of the tunnels, avoiding the articular cartilage and minimizing risk to the neurovascular structures. The distal end of the guide is inserted through a rotator interval portal and passed down to the axillary pouch. The proximal end of the guide is approximated to the greater tuberosity at the cuff footprint, and a complete transosseous tunnel is created with a 2.4-mm drill. An all-suture implant is inserted through this tunnel down to the calcar, and its deployment is visualized under arthroscopy. Gentle traction is applied to the anchor, resulting in a 4-mm concertina of the suture anchor that rests opposed to the medial cortex. The major advantage of this technique is the fixation strength gained from the biomechanically superior cortical bone of the calcar. Furthermore, this method permits greater preservation of bone surface area at the level of the footprint for a larger tendon-to-bone healing surface. This technique also provides an excellent alternative in revision situations. PMID:26052495

  16. Reinforced fixation of distal fibula fractures in elderly patients; A meta-analysis of biomechanical studies.

    Science.gov (United States)

    Dingemans, Siem A; Lodeizen, Olivia A P; Goslings, J Carel; Schepers, Tim

    2016-07-01

    There is an increasing incidence of fragility fractures of the ankle in the elderly population. The open reduction and internal fixation of these fractures is challenging, due to reduced bone stock quality as a result of osteoporosis. Biomechanical studies have shown contradicting results using reinforced constructions in the fixation of fibular fractures. We therefore performed a meta-analysis of biomechanical studies on reinforced fixation of distal fibular fractures. A literature search was conducted utilizing three online databases considering biomechanical testing of different fixation techniques of distal fibular fractures. A meta-analysis was performed on two biomechanical outcome measures; torsional stiffness and torque to failure. In a total number of 13 studies 8 different reinforcement techniques were identified. Of these studies, six compared locked lateral plating with conventional lateral plating. There were no statistically significant differences between the locking and non-locking lateral plate for torque to failure or torsional stiffness. Locked plating strength was independent from bone mineral density in four studies. An antiglide plate proved to be biomechanically superior compared to a lateral plate in one study and to a locked plate in another. Locked lateral plates are not biomechanically superior to conventional lateral plates. However the strength of locked plating may be independent of bone mineral density and could make this technique more suitable in the fixation of severe osteoporotic fractures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Comparison of Outcomes of Operatively Treated Bicondylar Tibial Plateau Fractures by External Fixation and Internal Fixation

    Directory of Open Access Journals (Sweden)

    CC Chan

    2012-03-01

    Full Text Available The outcome of bicondylar tibial plateau fractures treated with either external fixation (35 patients or internal fixation (24 patients was reviewed. Outcome measures included the Rasmussen score, clinical complications, development of osteoarthritis and the requirement for total knee replacement (TKR. Twenty-two (92% anatomical reductions were achieved in the internal fixation group compared to 27 (77% in the external fixation group. Infective complications were more common in the external fixation group (9 patients, 26% due to pin tract infection. There were no deep infections in the internal fixation group. The mean Rasmussen score was not significantly different (mean score 32 in external fixation and 29 in internal fixation between the two groups and the incidence of osteoarthritis was the same in both groups. Four patients in the external fixation group underwent a TKR compared to 5 patients in the internal fixation group. Bicondylar tibial plateau fractures have similar outcomes following external or internal fixation.

  18. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for use... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone cutting instrument and accessories. 872.4120...

  19. Surgical fixation of midshaft clavicle fractures: A systematic review of biomechanical studies.

    Science.gov (United States)

    Hulsmans, Martijn H; van Heijl, Mark; Houwert, Roderick M; Burger, Bart J; Verleisdonk, Egbert Jan M; Veeger, Dirk Jan; van der Meijden, Olivier A

    2018-02-21

    Surgical treatment of displaced midshaft clavicle fractures requires a decision between plate fixation and intramedullary (IM) fixation. Numerous studies report on the biomechanical properties of various repair constructs. The goal of this systematic review was to provide an overview of studies describing the biomechanical properties of the most commonly used surgical fixations of midshaft clavicle fractures. Additionally, we aimed to translate these biomechanical results into clinically relevant conclusions. A computer-aided search of the EMBASE and PudMed/MEDLINE databases was conducted. Studies included for review compared biomechanical properties of plate fixation with IM fixation and superiorly positioned plates with anteroinferiorly positioned plates for midshaft clavicle fractures. Fifteen studies were eligible for inclusion. Plate fixation seemed to form a more robust construct than IM fixation in terms of stiffness and failure loading. The remaining clavicle was stronger after removal of the IM device than after removal of the plate. Superior plating of transverse fractures generally seemed to provide greater stiffness and strength during bending loads than anteroinferior plating did. The absence of cortical alignment in wedge and comminuted fractures directly influenced the fixation stability for both IM fixation and plate fixation, regardless of location. Each type of fracture fixation has biomechanical advantages and disadvantages. However, exact thresholds of stiffness for inducing healing and failure strength to withstand refractures are unknown. The clinical relevance of the biomechanical studies may be arguable. Since none of the studies investigate the effect of tissue adaptation over time they should be interpreted with caution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Comparison of the Outcomes of Two Operational Methods Used for the Fixation of Calcaneal Fracture.

    Science.gov (United States)

    Wang, Qiang; Li, Xiaolei; Sun, Yu; Yan, Lianqi; Xiong, Chuanzhi; Wang, Jingcheng

    2015-05-01

    This study was aimed to compare the outcomes of two operational methods used for the fixation of calcaneal fracture, the open reduction using a plate and the minimally invasive cannulated screw fixations. Thus, we attempted to find out as to which of these fixation regimens was therapeutically superior by assessing improvement in the restoration of foot functioning and estimating the biochemical indices that reflect bone recovery. A total of 492 calcaneal fracture patients admitted in our hospital from February, 2008 to February, 2012 were selected for the study and randomly divided into two groups of 246 cases each. They were treated with either open reduction using a plate or minimally invasive cannulated screw fixation procedures. After the operations, patients were followed up for 2 years and the outcomes including functional restoration of calcaneus, the post-operational complications, and measure of the biochemical indicators of bone recovery were compared. The patients who underwent plate fixation procedure showed the excellent and good rate of 76.8 %. The minimally invasive cannulated screw fixation led to the excellent and good rate of 82.5 %. The angle, width, and height of calcaneus observed in the last follow-up were also improved significantly in the two groups (p 0.05). The post-operative complications occurred with the rates of 14.2 and 4.9 % in the patients treated with the plate and the minimally invasive cannulated screw fixations, respectively. The length of stay and hospitalization costs in the plate fixation group were 9.16 ± 0.83 days and 12,639.74 ± 2,573.82 Chinese Yuan, respectively. In comparison, in cannulated screw fixation group, the length of hospital stay (7.03 ± 0.52 days) and its cost (6,795.01 ± 996.53 Chinese Yuan) were significantly lower. Serum bone alkaline phosphatase and tartrate-resistant acid phosphatase-5b levels measured at the last follow-up examination were significantly altered (p 0.05). Plate screw and the

  1. Extracting information of fixational eye movements through pupil tracking

    Science.gov (United States)

    Xiao, JiangWei; Qiu, Jian; Luo, Kaiqin; Peng, Li; Han, Peng

    2018-01-01

    Human eyes are never completely static even when they are fixing a stationary point. These irregular, small movements, which consist of micro-tremors, micro-saccades and drifts, can prevent the fading of the images that enter our eyes. The importance of researching the fixational eye movements has been experimentally demonstrated recently. However, the characteristics of fixational eye movements and their roles in visual process have not been explained clearly, because these signals can hardly be completely extracted by now. In this paper, we developed a new eye movement detection device with a high-speed camera. This device includes a beam splitter mirror, an infrared light source and a high-speed digital video camera with a frame rate of 200Hz. To avoid the influence of head shaking, we made the device wearable by fixing the camera on a safety helmet. Using this device, the experiments of pupil tracking were conducted. By localizing the pupil center and spectrum analysis, the envelope frequency spectrum of micro-saccades, micro-tremors and drifts are shown obviously. The experimental results show that the device is feasible and effective, so that the device can be applied in further characteristic analysis.

  2. Measuring dwell time percentage from head-mounted eye-tracking data--comparison of a frame-by-frame and a fixation-by-fixation analysis.

    Science.gov (United States)

    Vansteenkiste, Pieter; Cardon, Greet; Philippaerts, Renaat; Lenoir, Matthieu

    2015-01-01

    Although analysing software for eye-tracking data has significantly improved in the past decades, the analysis of gaze behaviour recorded with head-mounted devices is still challenging and time-consuming. Therefore, new methods have to be tested to reduce the analysis workload while maintaining accuracy and reliability. In this article, dwell time percentages to six areas of interest (AOIs), of six participants cycling on four different roads, were analysed both frame-by-frame and in a 'fixation-by-fixation' manner. The fixation-based method is similar to the classic frame-by-frame method but instead of assigning frames, fixations are assigned to one of the AOIs. Although some considerable differences were found between the two methods, a Pearson correlation of 0.930 points out a good validity of the fixation-by-fixation method. For the analysis of gaze behaviour over an extended period of time, the fixation-based approach is a valuable and time-saving alternative for the classic frame-by-frame analysis.

  3. 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

  4. Staple versus locking compression plate fixation after lateral closing wedge high tibial osteotomy.

    Science.gov (United States)

    Agarwala, S; Shah, S B

    2008-12-01

    To compare the results of staple versus locking compression plate fixation after closing wedge high tibial osteotomy. A group of 23 patients (24 knees) who underwent box high tibial osteotomy and staple fixation was compared with another group of 19 patients (22 knees) who underwent a similar procedure but with locking compression plate fixation. Both groups were followed up for 3 years. The range of movement, Hospital for Special Surgery (HSS) Knee Score, time to full weight bearing, incidence of delayed union, femorotibial angle, and stage of osteoarthritis were compared. At 6 months after the operation, the median HSS score and the proportion of patients with excellent or good scores were significantly higher in the locking compression plate than the staple fixation group (76 vs 62, p=0.003; 75% vs 42%, p=0.0354), but not at one and 3 years. The range of movement was significantly greater in the locking compression plate fixation group in the short term (6 weeks, 3 and 6 months), but not after one year. The median time to full weight bearing was significantly shorter in the locking compression plate fixation group (86 vs 116 days, perror, in the femorotibial angle or correction loss between the 2 groups. Locking compression plate fixation obviates the use of plaster casts, enables early mobilisation and bone union, and reduces the numbers with delayed union and the time to full weight bearing. Longer-term studies are needed to evaluate its effect on revarisation and arthropathy.

  5. Hybrid fixation: evaluation of a novel technique in adult osteochondritis dissecans of the knee.

    Science.gov (United States)

    Lintz, Francois; Pujol, Nicolas; Pandeirada, Christophe; Boisrenoult, Philippe; Beaufils, Philippe

    2011-04-01

    Treatment of osteochondritis dissecans of the adult knee requires bone and cartilage integration of the loose fragment. Screw fixation provides primary stability but does not guarantee bony consolidation. Additional biological fixation using osteochondral grafts-hybrid fixation-could improve fragment integration. The study included seven patients [median age 21 years (15-29)] who underwent surgery for Bedouelle IIB or III osteochondritis dissecans of the medial femoral condyle. The technique involved metal screw fixation of the fragment. Mosaicplasty grafts were then press-fitted through the fragment. Cancellous autograft was utilized in the cases of subchondral bone loss. Patients were followed up clinically and radiologically (Hughston score). Screws were removed arthroscopically at 3 months and the cartilage graded using the International Cartilage Repair Society score. Fragment integration was evaluated by MRI Arthrogram (4 patients). Median follow-up was 27 months (7-35). Median clinical Hughston score was 2 (0-3) preoperatively and 4 (2-4) postoperatively. Median radiological Hughston score was 3 (2-4) and 4 (3-4). During arthroscopic removal of metalwork, osteochondritis fragments were well integrated in all cases. The International Cartilage Repair Society score was I in one patients, II in five, and III in one. Postoperative MRI arthrograms confirmed that cartilage and bone integration was complete. Isolated screw fixation of osteochondritis dissecans in adults provides poor bony integration. Mosaicplasty is an alternative but does not retain normal condylar anatomy. The hybrid fixation technique adds a biological "booster" to osteochondritis fixation, with excellent short-term outcome. Further studies are required to investigate the long-term results.

  6. Surgical treatment of neglected clubfoot using external fixator.

    Science.gov (United States)

    Fernandes, Rodrigo Mota Pacheco; Mendes, Maurilio Darcy Dos Santos; Amorim, Renato; Preti, Marcus Aurélio; Sternick, Marcelo Back; Gaiarsa, Guilherme Pelosini

    2016-01-01

    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.

  7. 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.

  8. 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

  9. SURGICAL TREATMENT OF PATIENTS WITH HALLUX VALGUS BY MINI-APPARATUS OF EXTERNAL FIXATION

    Directory of Open Access Journals (Sweden)

    K.K. Levchenko

    2008-06-01

    Full Text Available The authors of article suggest methods of surgical correction of pathology by means of fixation of the first metatarsal bone with specialconstruction ofmini-apparatus for externalfixation. This approach provides decrease of recovery period, reduces complications riskas well as deformation relapse.

  10. 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. © IMechE 2014.

  11. Bone mineral density measurement over the shoulder region

    DEFF Research Database (Denmark)

    Doetsch, A M; Faber, J; Lynnerup, N

    2002-01-01

    values decreased with age (P shoulder BMD levels increased significantly with increased body mass index (BMI) (P positive relationship between the increased hip/shoulder BMD differential with BMI supports the conclusion that the shoulder is subject......The purpose of this study was to (1). establish a method for measuring bone mineral density (BMD) over the shoulder region; (2). compare the relationship between shoulder BMD levels with hip BMD and body mass index (BMI); and (3). discuss the relevance of the shoulder scan as an early indicator...... of osteoporosis compared with hip scans, the latter representing a weight-bearing part of the skeleton. We developed a scanning procedure, including a shoulder fixation device, and determined the most appropriate software in order to establish a reference material with the highest possible precision. Duplicate...

  12. Torsional force applied to the tibia of living lambs in an attempt to change the bone rotational axis.

    Science.gov (United States)

    Volpon, José Batista; Falcai, Maurício José; Moro, Carlos Alberto; Leal, Daniel Mendes

    2014-03-01

    To evaluate the effects of torsional force on the rotational axis of living lamb tibias. An external fixator device was designed to apply rotation to the tibias of lambs. Once a week, the bone distal extremity was rotated 2º. After achieving ~20º of internal rotation, the turning was discontinued and the device was maintained in situ for one month and euthanasia occurred in group A (n=10) after this. In group B (n=9) euthanasia occurred three months after removing the device. Computed tomography scans evaluated the rotational angle; dual-energy X-ray absorptiometry assessed the bone mineral density, and conventional and polarized light microscopy studied the bone microstructure. In group A, the mean angle of the external rotation in the control tibias was 24º and 8º in the twisted tibias (p0.05). Microscopically, the twisted tibias showed asymmetrical subperiosteal bone deposition on the lateral cortex surface. Gradual torsion applied to the immature tibia significantly modified its rotational axis.

  13. 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. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  14. [Healing of spiral fractures in the sheep tibia comparing different methods--osteosynthesis with internal fixation, interlocking nailing and dynamic compression plate].

    Science.gov (United States)

    Seibold, R; Schlegel, U; Kessler, S B; Cordey, J; Perren, S M; Schweiberer, L

    1995-12-01

    The healing process of spiral fractures of the sheep tibia was investigated in an experiment with simulated clinical conditions. The effects of conventional internal fixation techniques with the DCP and the intramedullary nail are compared with those of internal fixation with the spine fixator. The internal fixation techniques are described in terms of their bending stiffness when mounted on the fractured bone. The in vivo investigation was documented clinically and radiographically and the post mortem specimens were evaluated histologically. The bending stiffness of the healed bone was assessed in relation to the contralateral side. After application of the DCP, primary healing took place and extensive transcortical necrosis occurred in the implant bed. Intramedullary nailing led to secondary healing and to necrosis of the inner cortex close to the endosteum. After internal fixation with the spine fixator, gap healing took place and no cortical necrosis was observed. The clinical course was generally good after all procedures. The histological evaluation shows that damage to the vascularity of the bone can only be avoided by using the spine fixator. This principle seems to be appropriate for the purposes of biological internal fixation.

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

    Directory of Open Access Journals (Sweden)

    Ghassan Kerry

    2013-09-01

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

  16. Anterior double plating for rigid fixation of isolated tibiotalar arthrodesis.

    Science.gov (United States)

    Plaass, Christian; Knupp, Markus; Barg, Alexej; Hintermann, Beat

    2009-07-01

    Arthrodesis is the most common procedure used to treat end-stage osteoarthritis of the ankle, particularly in patients with difficult conditions such as poor bone quality. While many techniques are available to fuse the ankle, current recommendations favor the use of internal fixation with screws and/or plates. Despite of progress, the complication rate remains a major concern. Non-union is one difficult problem especially with difficult bone conditions, particularly the loss of bone stock on the talar side. Therefore, fusion of the tibiotalar joint is often extended to the talocalcaneal joint to provide sufficient stability. To preserve the subtalar joint, an anterior double plate system for rigid fixation of isolated tibiotalar arthrodesis was developed. This is a preliminary report on the clinical and radiological outcome with this technique. Twenty-nine patients (15 men, 14 women; one ankle per patient) were treated from October 2006 to September 2007. We converted 16 ankles with osteoarthritis and difficult bone conditions, four non-united ankle arthrodeses, and nine failed total ankle replacements to an isolated tibiotalar arthrodesis using anterior double plating. If necessary, we used solid allograft to fill bony defects. Outcomes included bone union as assessed by radiographs, pain as indicated by the American Orthopaedic Foot and Ankle Society scores, and patient satisfaction. Solid arthrodesis was achieved after an average of 12.3 (eight to 26) weeks in the 16 ankles without bone graft interposed between the tibia and talus, and 14.3 (range, 8 to 26) weeks in the 13 ankles with interpositional bone allograft. Radiographs showed that the position of arthrodesis obtained at the time of surgery did not change in any patient up to one year after surgery. The mean American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot Score increased from 37 (range, 20 to 63) preoperatively to 68 (range, 50 to 92) at the last followup. Twenty-seven patients (93%) were

  17. Bone Conduction: Anatomy, Physiology, and Communication

    National Research Council Canada - National Science Library

    Henry, Paula; Letowski, Tomasz R

    2007-01-01

    .... This report combines results of an extensive literature review of the anatomy and physiology of human hearing, theories behind the mechanisms of bone conduction transmission, devices for use in bone...

  18. Bone Conduction: Anatomy, Physiology, and Communication

    National Research Council Canada - National Science Library

    Henry, Paula; Letowski, Tomasz R

    2007-01-01

    ... conduction transmission, and the use of the bone conduction pathway for communication. Bone conduction for the transmission of communication is effective and feasible for Soldiers because it provides a means of providing radio communication in combination with hearing protection devices.

  19. External fixation to correct tarsal-metatarsal fracture in rock pigeon (Columba livia

    Directory of Open Access Journals (Sweden)

    Leandro Almeida Rui

    Full Text Available ABSTRACT Orthopedic conditions, such as bone fractures, are very common in avian medicine. External fixators have been considered the gold standard for birds, since they allow early movement of the limbs and minimal invasive surgery. Fractures in several bones have been successfully treated in pigeons. However, to the best of our knowledge, this case represents the first report of successful surgical repair of tarsal-metatarsal fracture in rock pigeon. External fixator was made with four 24G catheters, being inserted manually proximal and distal to the fracture and connected with polymerizable acrylic. Radiographic consolidation of fracture was observed 60 days post-surgery and anti-inflammatory and antibiotic protocols were successful on avoiding pain and infection during surgery and bone healing.

  20. Ilizarov fixator in management of nonunited and infected tibial shaft fractures

    Directory of Open Access Journals (Sweden)

    Abhinay Singh

    2015-01-01

    Full Text Available Background: Management of nonunion with bony defect and infection in long bones is a challenging problem for orthopedic surgeons. Objectives: Evaluation of Ilizarov circular fixation method of treatment for the management of nonunited and infected fractures of tibia. Materials and Methods: This prospective study was conducted in a tertiary care hospital of eastern region of India on 30 subjects in a time span of 3 years after taking clearance of the Institutional Ethical Committee and informed consent of the patients. Results: All the patients had infected nonunion before undergoing Ilizarov procedure. Following initial injury, 22 patients were treated with external fixation and 8 cases were treated with internal fixation. At the time of presentation, 18 patients had infected gap nonunion, 5 patients had infected hypertrophic and 2 patients had atrophic nonunion. The Ilizarov fixator was kept for an average period of 303.7 days. Based on Association for the Study and Application of Methods of Ilizarov scoring system, bony and functional results were assessed. The bony result was excellent in 16 patients, good in eight, fair in four and poor in two. The functional result was excellent in 10 patients, good in 16, fair in two, poor in two. Conclusion: Ilizarov ring fixator still remains an excellent treatment modality for tibial nonunion with a defect, regarding bone union, deformity correction, infection eradication, limb-length achievement, and limb function.

  1. Role of Appositional Screw Fixation in Minimally Invasive Plate Osteosynthesis for Distal Tibial Fracture.

    Science.gov (United States)

    Yang, Kyu-Hyun; Won, Yougun; Kang, Dong-Hyun; Oh, Jin-Cheol; Kim, Sung-Jun

    2015-09-01

    To determine the effect of interfragmentary appositional (gap-closing) screw fixation in minimally invasive plate osteosynthesis (MIPO) for distal tibial fractures on the clinical and radiologic results. Prospective nonrandomized study. Level I trauma center. Sixty patients who were diagnosed as distal metadiaphyseal oblique or spiral tibial fracture without displaced articular fragment. Thirty patients (group A) of the 60 patients were treated with MIPO without appositional screw fixation, and the other 30 (group B) were treated with the screw. Radiologic union, clinical union, clinical functional score [American Orthopaedic Foot and Ankle Society (AOFAS) score], and complications. The time for initial callus formation and radiologic union was significantly longer in group A than those in group B (76.8 vs. 58.0 days, P = 0.044; 409 vs. 258.7 days, P = 0.002, respectively). The rate of clinical union during 1 year was significantly higher in group B than in group A (P = 0.0063). Four nonunion patients in group A achieved bone union after placement of an additional bone graft. None of the patients in group B diagnosed with delayed union or nonunion (P screw fixation in distal tibia MIPO for the fixation of oblique or spiral fracture promoted callus formation and union rate compared with MIPO without appositional screw fixation. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

  2. 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.

  3. Smaller Fixation Target Size Is Associated with More Stable Fixation and Less Variance in Threshold Sensitivity.

    Directory of Open Access Journals (Sweden)

    Kazunori Hirasawa

    Full Text Available The aims of this randomized observational case control study were to quantify fixation behavior during standard automated perimetry (SAP with different fixation targets and to evaluate the relationship between fixation behavior and threshold variability at each test point in healthy young participants experienced with perimetry. SAP was performed on the right eyes of 29 participants using the Octopus 900 perimeter, program 32, dynamic strategy. The fixation targets of Point, Cross, and Ring were used for SAP. Fixation behavior was recorded using a wearable eye-tracking glass. All participants underwent SAP twice with each fixation target in a random fashion. Fixation behavior was quantified by calculating the bivariate contour ellipse area (BCEA and the frequency of deviation from the fixation target. The BCEAs (deg2 of Point, Cross, and Ring targets were 1.11, 1.46, and 2.02, respectively. In all cases, BCEA increased significantly with increasing fixation target size (p < 0.05. The logarithmic value of BCEA demonstrated the same tendency (p < 0.05. A positive correlation was identified between fixation behavior and threshold variability for the Point and Cross targets (ρ = 0.413-0.534, p < 0.05. Fixation behavior increased with increasing fixation target size. Moreover, a larger fixation behavior tended to be associated with a higher threshold variability. A small fixation target is recommended during the visual field test.

  4. Arthroscopic internal fixation of osteochondritis dissecans of the femoral head.

    Science.gov (United States)

    Matsuda, Dean K; Safran, Marc R

    2013-05-01

    Osteochondritis dessicans of the femoral head is an uncommon problem. Limited literature reports the incidence of osteochondritis dessicans and its treatment. The surgical technique used and outcomes for a 40-year-old man with symptomatic femoral head osteochonditis dissecans who was treated 11 years previously with retrograde drilling and hip arthroscopy are discussed.Despite temporary symptomatic improvement without subchondral collapse after his index procedure, increasing pain a decade later was thought to be caused by a large apical osteochondritic fragment and chondrolabral dysfunction from femoroacetabular impingement. Acetabuloplasty of acetabular overcoverage permitted arthroscopic internal fixation of the bone fragment by improving screw trajectory. Labral refixation and femoroplasty were subsequently performed. At 18-month follow-up, his nonarthritic hip score improved from 53 to 76 and his osteochondritic lesion had healed radiographically.Although clinical improvement with radiographic union has been reported following open screw fixation of femoral head osteochondritis dissecans, to the authors' knowledge this is the first published case with a similar outcome using arthroscopic techniques. Clinical improvement and union of even long-standing osteochondritis dissecans of the femoral head may occur with arthroscopic fragment fixation. Hip arthroscopy may play significant therapeutic and diagnostic roles in the treatment of this condition while offering a less invasive alternative to open osteosynthesis. Copyright 2013, SLACK Incorporated.

  5. Embalmed and fresh frozen human bones in orthopedic cadaveric studies: which bone is authentic and feasible?

    OpenAIRE

    Topp, Tobias; Müller, Thorben; Huss, Sebastian; Kann, Peter Herbert; Weihe, Eberhard; Ruchholtz, Steffen; Zettl, Ralph Peter

    2012-01-01

    Background and purpose The most frequently used bones for mechanical testing of orthopedic and trauma devices are fresh frozen cadaveric bones, embalmed cadaveric bones, and artificial composite bones. Even today, the comparability of these different bone types has not been established. Methods We tested fresh frozen and embalmed cadaveric femora that were similar concerning age, sex, bone mineral density, and stiffness. Artificial composite femora were used as a reference group. Testing para...

  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. 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.

  8. Abnormal Fixational Eye Movements in Amblyopia.

    Science.gov (United States)

    Shaikh, Aasef G; Otero-Millan, Jorge; Kumar, Priyanka; Ghasia, Fatema F

    2016-01-01

    Fixational saccades shift the foveal image to counteract visual fading related to neural adaptation. Drifts are slow eye movements between two adjacent fixational saccades. We quantified fixational saccades and asked whether their changes could be attributed to pathologic drifts seen in amblyopia, one of the most common causes of blindness in childhood. Thirty-six pediatric subjects with varying severity of amblyopia and eleven healthy age-matched controls held their gaze on a visual target. Eye movements were measured with high-resolution video-oculography during fellow eye-viewing and amblyopic eye-viewing conditions. Fixational saccades and drifts were analyzed in the amblyopic and fellow eye and compared with controls. We found an increase in the amplitude with decreased frequency of fixational saccades in children with amblyopia. These alterations in fixational eye movements correlated with the severity of their amblyopia. There was also an increase in eye position variance during drifts in amblyopes. There was no correlation between the eye position variance or the eye velocity during ocular drifts and the amplitude of subsequent fixational saccade. Our findings suggest that abnormalities in fixational saccades in amblyopia are independent of the ocular drift. This investigation of amblyopia in pediatric age group quantitatively characterizes the fixation instability. Impaired properties of fixational saccades could be the consequence of abnormal processing and reorganization of the visual system in amblyopia. Paucity in the visual feedback during amblyopic eye-viewing condition can attribute to the increased eye position variance and drift velocity.

  9. Abnormal fixational eye movements in strabismus.

    Science.gov (United States)

    Ghasia, Fatema F; Otero-Millan, Jorge; Shaikh, Aasef G

    2018-02-01

    Fixational saccades are miniature eye movements that constantly change the gaze during attempted visual fixation. Visually guided saccades and fixational saccades represent an oculomotor continuum and are produced by common neural machinery. Patients with strabismus have disconjugate binocular horizontal saccades. We examined the stability and variability of eye position during fixation in patients with strabismus and correlated the severity of fixational instability with strabismus angle and binocular vision. Eye movements were measured in 13 patients with strabismus and 16 controls during fixation and visually guided saccades under monocular viewing conditions. Fixational saccades and intersaccadic drifts were analysed in the viewing and non-viewing eye of patients with strabismus and controls. We found an increase in fixational instability in patients with strabismus compared with controls. We also found an increase in the disconjugacy of fixational saccades and intrasaccadic ocular drift in patients with strabismus compared with controls. The disconjugacy was worse in patients with large-angle strabismus and absent stereopsis. There was an increase in eye position variance during drifts in patients with strabismus. Our findings suggest that both fixational saccades and intersaccadic drifts are abnormal and likely contribute to the fixational instability in patients with strabismus. Fixational instability could be a useful tool for mass screenings of children to diagnose strabismus in the absence of amblyopia and latent nystagmus. The increased disconjugacy of fixational eye movements and visually guided saccades in patients with strabismus reflects the disruption of the fine-tuning of the motor and visual systems responsible for achieving binocular fusion in these patients. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. History of internal fixation (part 1): early developments with wires and plates before World War II.

    Science.gov (United States)

    Hernigou, Philippe; Pariat, Jacques

    2017-06-01

    Though the date at which an orthopaedic implant was first used cannot be ascertained with any certainty, the fixation of bone fracture using an iron wire was reported for the first time in a French manuscript in 1775. The first techniques of operative fracture treatment were developed at the end of the 18th and in the beginning of the 19th centuries. The use of cerclage wires to fix fractures was the most frequent fixation at this time. The French Berenger-Feraud (1832-1900) had written the first book on internal fixation. However internal fixation of fractures could not become a practical method before Lister had ensured the safety of open reduction and internal fixation in the treatment of fractures. Lister is not only the father of asepsis; he also used metal wires to fix even closed fractures. The first internal fixation by means of a plate and screws was described by Carl Hansmann in 1858 in Hamburg. Nevertheless, Arbuthnot Lane (1892) and Albin Lambotte (1905) are considered to be the founders of this method, which was further developed by Sherman in the first part of the 20th century.

  11. The effects of fixation of the ulna to the radius in young foals

    International Nuclear Information System (INIS)

    Clem, M.F.; DeBowes, R.M.; Douglass, J.P.; Leipold, H.W.; Chalman, J.A.

    1988-01-01

    The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixation and was accompanied by degenerative joint disease and lameness in foals undergoing fixation at 1 and 5 months of age. Removal of the fixation appliances 16 weeks after implantation in three foals from each of groups I and II failed to reverse the degree of ulnar dysplasia. Although foals undergoing fixation at 7 months of age (group III) were not lame, radiographic evidence of subluxation and subtle degenerative changes in the articular cartilage of the treated elbow did develop. Recommendations for avoidance of radioulnar fixation were developed from these observations

  12. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

    Directory of Open Access Journals (Sweden)

    Wegner Alexander

    2012-06-01

    Full Text Available Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operative positions of the hip rotation center in 25 and 68 patients who underwent artificial hip replacements in our department in 2007 using cemented or cementless cup fixation, respectively, with digital radiographic image analysis. Results The mean horizontal and vertical distances between the rotation center and the acetabular teardrop were compared in radiographic images taken pre- and post-operatively. The mean horizontal difference was −2.63 mm (range: -11.00 mm to 10.46 mm, standard deviation 4.23 mm for patients who underwent cementless fixation, and −2.84 mm (range: -10.87 to 5.30 mm, standard deviation 4.59 mm for patients who underwent cemented fixation. The mean vertical difference was 0.60 mm (range: -20.15 mm to 10.00 mm, standard deviation 3.93 mm and 0.41 mm (range: -9.26 mm to 6.54 mm, standard deviation 3.58 mm for the cementless and cemented fixation groups, respectively. The two fixation techniques had no significant difference on the position of the hip rotation center in the 93 patients in this study. Conclusions The hip rotation center was similarly restored using either the cemented or cementless fixation techniques in this patient cohort, indicating that the fixation technique itself does not interfere with the position of the center of rotation. To completely answer this question further studies with more patients are needed.

  13. Implant failure in osteosynthesis of fractures of long bones ...

    African Journals Online (AJOL)

    Patients who had open operative treatment of fractures of long bones were reviewed retrospectively to identify the incidence of and risk factors for implant failure. One hundred and five patients had open reduction and internal fixation of 117 fractures of long bones, out of which four patients suffered implant failure.

  14. Relative motion at the bone-prosthesis interface

    NARCIS (Netherlands)

    Keja, M.; Wevers, H.W.; Siu, D.; Grootenboer, H.J.

    1994-01-01

    Bone ingrowth in porous surfaces of human joint implants is a desired condition for long-term fixation in patients who are physically active (such as in sport or work). It is generally recognized that little actual bone ingrowth occurs. The best clinical results report between 10 and 20% of the

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  16. Postoperative complications associated with external skeletal fixators in cats.

    Science.gov (United States)

    Beever, Lee; Giles, Kirsty; Meeson, Richard

    2017-07-01

    The objective of this study was to quantify complications associated with external skeletal fixators (ESFs) in cats and to identify potential risk factors. A retrospective review of medical records and radiographs following ESF placement was performed. Case records of 140 cats were reviewed; fixator-associated complications (FACs) occurred in 19% of cats. The region of ESF placement was significantly associated with complication development. Complications developed most frequently in the femur (50%), tarsus (35%) and radius/ulna (33%). Superficial pin tract infection (SPTI) and implant failure accounted for 45% and 41% of all FACs, respectively. SPTI occurred more frequently in the femur, humerus and tibia, with implant failure more frequent in the tarsus. No association between breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, degree of fracture load sharing, and the incidence or type of FAC was identified. No association between region of placement, breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, fracture load sharing and the time to complication development was identified. Complication development is not uncommon in cats following ESF placement. The higher complication rate in the femur, tarsus and radius/ulna should be considered when reviewing options for fracture management. However, cats appear to have a lower rate of pin tract infections than dogs.

  17. Noninvasive patient fixation for extracranial stereotactic radiotherapy

    International Nuclear Information System (INIS)

    Lohr, Frank; Debus, Juergen; Frank, Claudia; Herfarth, Klaus; Pastyr, Otto; Rhein, Bernhard; Bahner, Malte L.; Schlegel, Wolfgang; Wannenmacher, Michael

    1999-01-01

    Purpose: To evaluate the setup accuracy that can be achieved with a novel noninvasive patient fixation technique based on a body cast attached to a recently developed stereotactic body frame during fractionated extracranial stereotactic radiotherapy. Methods and Materials: Thirty-one CT studies (≥ 20 slices, thickness: 3 mm) from 5 patients who were immobilized in a body cast attached to a stereotactic body frame for treatment of para medullary tumors in the thoracic or lumbar spine were evaluated with respect to setup accuracy. The immobilization device consisted of a custom-made wrap-around body cast that extended from the neck to the thighs and a separate head mask, both made from Scotchcast. Each CT study was performed immediately before or after every second or third actual treatment fraction without repositioning the patient between CT and treatment. The stereotactic localization system was mounted and the isocenter as initially located stereo tactically was marked with fiducials for each CT study. Deviation of the treated isocenter as compared to the planned position was measured in all three dimensions. Results: The immobilization device can be easily handled, attached to and removed from the stereotactic frame and thus enables treatment of multiple patients with the same stereotactic frame each day. Mean patient movements of 1.6 mm ± 1.2 mm (laterolateral [LL]), 1.4 mm ± 1.0 mm (anterior-posterior [AP]), 2.3 mm ± 1.3 mm (transversal vectorial error [VE]) and < slice thickness = 3 mm (cranio caudal [CC]) were recorded for the targets in the thoracic spine and 1.4 mm ± 1.0 mm (LL), 1.2 mm ± 0.7 mm (AP), 1.8 mm ± 1.2 mm (VE), and < 3 mm (CC) for the lumbar spine. The worst case deviation was 3.9 mm for the first patient with the target in the thoracic spine (in the LL direction). Combining those numbers (mean transversal VE for both locations and maximum CC error of 3 mm), the mean three-dimensional vectorial patient movement and thus the mean overall

  18. A device for temporomandibular joint exercise and trismus correction: design and clinical application.

    Science.gov (United States)

    Lo, Lun-Jou; Lin, Chun-Li; Chen, Yu-Ray

    2008-01-01

    Temporomandibular joint (TMJ) hypomobility and trismus is a frequently seen clinical condition, and rehabilitation with mouth-opening exercises is mandatory for fast and successful recovery. As conventional methods and available devices are not without disadvantages, a new TMJ exerciser has been developed and clinically tested. The new device was designed and made using a computer-aided design/computer-aided manufacture program. The mouthpiece is opened using a power screw technique. The device was revised until it became acceptable for clinical trials. Nineteen patients with TMJ hypomobility or trismus used the new device: five after surgical release of TMJ ankylosis, five after facial fracture reduction and intermaxillary fixation, three after blunt facial trauma, five following orthognathic surgery, and one following facial bone-contouring surgery. The outcome was evaluated. The new TMJ exercise appliance was convenient, durable and easy to use. The maximal incisor opening was 16.3+/-7.1 mm before use of the device, and 34.2+/-6.3 mm after the treatment period (P<0.05). Fourteen patients (74%), i.e. all except the five with release of ankylosis, recovered to normal range of mouth opening at longitudinal follow up. There was no mechanical failure and no complications from using the device, and the patients were satisfied. The new exerciser is a satisfactory device for physiotherapy of TMJ hypomobility and trismus.

  19. A 2-screw fixation technique for subtalar joint fusion: a retrospective case series introducing a novel 2-screw fixation construct with operative pearls.

    Science.gov (United States)

    Boffeli, Troy J; Reinking, Ryan R

    2012-01-01

    A variety of fixation methods are used in fusion of the subtalar joint (STJ) including 1 screw and 2 screw constructs. The rate of union is generally high for STJ fusion, regardless of the fixation method, provided the joint surfaces have been properly prepared and compressed and the patient avoids premature stress on the fusion site. Certain populations are known to have an increased risk of nonunion or delayed union including diabetics, smokers, and those undergoing revision of failed fusion. In this high-risk patient population, we propose that our novel 2-screw construct might have advantages over traditional fixation constructs without identified disadvantages. The technique is simple enough to be used in all primary and revision STJ fusion procedures, and this has become our practice. In the present study, 15 feet in 15 consecutive patients who underwent STJ fusion using a novel 2-screw fixation construct were retrospectively reviewed to assess the fusion outcome and complications. Specifically, we offer a novel 2-screw construct that offers the stability of the traditional parallel 2-screw construct while maintaining a maximum raw bone surface area at the posterior facet achieved by single-screw fixation. A retrospective review of radiographs taken 10 weeks postoperatively indentified a 100% fusion rate (15 of 15). All patients in our series achieved fusion, including several high-risk cases, and no significant complications were identified. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Can a modified anterior external fixator provide posterior compression of AP compression type III pelvic injuries?

    Science.gov (United States)

    Sellei, Richard Martin; Schandelmaier, Peter; Kobbe, Philipp; Knobe, Matthias; Pape, Hans-Christoph

    2013-09-01

    Current anterior fixators can close a disrupted anterior pelvic ring. However, these anterior constructs cannot create posterior compressive forces across the sacroiliac joint. We explored whether a modified fixator could create such forces. We determined whether (1) an anterior external fixator with a second anterior articulation (X-frame) would provide posterior pelvic compression and (2) full pin insertion would deliver higher posterior compressive forces than half pin insertion. We simulated AP compression Type III instability with plastic pelvis models and tested the following conditions: (1) single-pin supraacetabular external fixator (SAEF) using half pin insertion (60 mm); (2) SAEF using full pin insertion (120 mm); (3) modified fixator with X-frame using half pin insertion; (4) modified fixator using full pin insertion; and (5) C-clamp. Standardized fracture compression in the anterior and posterior compartment was performed as in previous studies by Gardner. A force-sensitive sensor was placed in the symphysis and posterior pelvic ring before fracture reduction and the fractures were reduced. The symphyseal and sacroiliac compression loads of each application were measured. The SAEF exerted mean compressions of 13 N and 14 N to the posterior pelvic ring using half and full pin insertions, respectively. The modified fixator had mean posterior compressions of 174 N and 222 N with half and full pin insertions, respectively. C-clamp application exerted a mean posterior load of 407 N. Posterior compression on the pelvis was improved using an X-frame as an anterior fixation device in a synthetic pelvic fracture model. This additive device may improve the initial anterior and posterior stability in the acute management of unstable and life-threatening pelvic ring injuries.