WorldWideScience

Sample records for mechanical-biological graft fixation

  1. 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.

  2. Meniscal allograft transplantation. Part 1: systematic review of graft biology, graft shrinkage, graft extrusion, graft sizing, and graft fixation.

    Science.gov (United States)

    Samitier, Gonzalo; Alentorn-Geli, Eduard; Taylor, Dean C; Rill, Brian; Lock, Terrence; Moutzouros, Vasilius; Kolowich, Patricia

    2015-01-01

    To provide a systematic review of the literature regarding five topics in meniscal allograft transplantation: graft biology, shrinkage, extrusion, sizing, and fixation. A systematic literature search was conducted using the PubMed (MEDLINE), ScienceDirect, and EBSCO-CINAHL databases. Articles were classified only in one topic, but information contained could be reported into other topics. Information was classified according to type of study (animal, in vitro human, and in vivo human) and level of evidence (for in vivo human studies). Sixty-two studies were finally included: 30 biology, 3 graft shrinkage, 11 graft extrusion, 17 graft size, and 6 graft fixation (some studies were categorized in more than one topic). These studies corresponded to 22 animal studies, 22 in vitro human studies, and 23 in vivo human studies (7 level II, 10 level III, and 6 level IV). The principal conclusions were as follows: (a) Donor cells decrease after MAT and grafts are repopulated with host cells form synovium; (b) graft preservation alters collagen network (deep freezing) and causes cell apoptosis with loss of viable cells (cryopreservation); (c) graft shrinkage occurs mainly in lyophilized and gamma-irradiated grafts (less with cryopreservation); (d) graft extrusion is common but has no clinical/functional implications; (e) overall, MRI is not superior to plain radiograph for graft sizing; (f) graft width size matching is more important than length size matching; (g) height appears to be the most important factor influencing meniscal size; (h) bone fixation better restores contact mechanics than suture fixation, but there are no differences for pullout strength or functional results; and (i) suture fixation has more risk of graft extrusion compared to bone fixation. Systematic review of level II-IV studies, Level IV.

  3. 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.

  4. Skin Graft Fixation Using Hydrofiber (Aquacel® Extra).

    Science.gov (United States)

    Yen, Ya-Hui; Lin, Chih-Ming; Hsu, Honda; Chen, Ying-Chen; Chen, Yi-Wen; Li, Wan-Yu; Hsieh, Chia-Nan; Huang, Chieh-Chi

    2018-06-01

    The traditional method of skin graft fixation is with tie-over bollus dressing. The use of splints in the extremities for skin graft fixation is a common practice. However, these splints are heavy and uncomfortable and contribute considerably to our overall medical waste. Hydrofiber (Aquacel Extra) has a strong fluid absorption property and fixates well to the underlying wound once applied. In this study, we used hydrofiber for fixation, avoiding the use of splints after skin grafting. A total of 56 patients reconstructed with split-thickness skin graft that was fixated only with hydrofiber between March 2015 and March 2016 were included in this retrospective study. There were 44 men and 12 women with a mean age of 61 ± 18 years. The defect size ranged from 1 × 1 cm for fingertips to 30 × 12 cm for lower limb defects. The average defect size was 61 ± 78 cm. The mean skin graft take was 96% ± 6%. Because splints were not required, we saved around 48 kg of medical waste over the space of 1 year. The use of hydrofiber for skin graft fixation was effective and technically very simple. Splints were not required with this method, decreasing the medical waste created and increasing patient comfort. We suggest that this is an excellent alternative for skin graft fixation while at the same time decreasing our carbon footprint as surgeons.

  5. Novel anterior cruciate ligament graft fixation device reduces slippage

    Directory of Open Access Journals (Sweden)

    Lopez MJ

    2013-05-01

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

  6. 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

  7. 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...... the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking...

  8. Role of graft oversizing in the fixation strength of barbed endovascular grafts.

    Science.gov (United States)

    Kratzberg, Jarin A; Golzarian, Jafar; Raghavan, Madhavan L

    2009-06-01

    The role of endovascular graft oversizing on risk of distal graft migration following endovascular aneurysm repair for abdominal aortic aneurysm is poorly understood. A controlled in vitro investigation of the role of oversizing in graft-aorta attachment strength for endovascular grafts (EVGs) with barbs was performed. Barbed stent grafts (N = 20) with controlled graft oversizing varying from 4-45% were fabricated while maintaining other design variables unchanged. A flow loop with physiological flow characteristics and a biosynthetic aortic aneurysm phantom (synthetic aneurysm model with a bovine aortic neck) were developed. The stent grafts were deployed into the aortic neck of the bio-synthetic aortic aneurysm phantom under realistic flow conditions. Computed tomography imaging of the graft-aorta complex was used to document attachment characteristics such as graft apposition, number of barbs penetrated, and penetration depth and angle. The strength of graft attachment to the aortic neck was assessed using mechanical pullout testing. Stent grafts were categorized into four groups based on oversizing: 4-10%; 11-20%; 21-30%; and greater than 30% oversizing. Pullout force, a measure of post-deployment fixation strength was not different between 4-10% (6.23 +/- 1.90 N), 11-20% (6.25 +/- 1.84 N) and 20-30% (5.85 +/- 1.89 N) groups, but significantly lower for the group with greater than 30% oversizing (3.67 +/- 1.41 N). Increasing oversizing caused a proportional decrease in the number of barbs penetrating the aortic wall (correlation = -0.83). Of the 14 barbs available in the stent graft, 89% of the barbs (12.5 of 14 on average) penetrated the aortic wall in the 4-10% oversizing group while only 38% (5.25 of 14) did for the greater than 30% group (P barb penetration were found to be positively correlated to pullout force. Greater than 30% graft oversizing affects both barb penetration and graft apposition adversely resulting in a low pullout force in this in vitro

  9. An alternative graft fixation technique for scaphoid nonunions treated with vascular bone grafting.

    Science.gov (United States)

    Korompilias, Anastasios V; Lykissas, Marios G; Kostas-Agnantis, Ioannis P; Gkiatas, Ioannis; Beris, Alexandros E

    2014-07-01

    To present our experience with vascularized bone grafting based on the 1,2-intercompartmental supraretinacular artery for the management of established scaphoid nonunion and to investigate the efficacy of graft immobilization with a combination of Kirschner wires and transarticular external fixation. A retrospective chart and radiographic review was conducted for patients with the diagnosis of scaphoid nonunion of the proximal pole or the waist treated with the 1,2-intercompartmental supraretinacular artery-based vascularized graft and fixed with a combination of Kirschner wires and transarticular external fixation between 2007 and 2011. We observed 23 consecutive patients for a mean of 34 ± 4 months. All patients were males with mean age of 25 ± 5 years. All patients had scaphoid nonunion and associated humpback deformity. The mean duration of nonunion was 7 ± 1 months. All scaphoid nonunions united after the index procedure at a mean of 10 ± 1 weeks. Two patients had avascular necrosis of the proximal pole based on the preoperative magnetic resonance imaging findings. After surgery, deformity correction was achieved in all patients, as recorded by the decrease in the lateral intrascaphoid angle and the increase in the dorsal scaphoid angle. At the last follow-up, no patients reported wrist pain. The mean Disabilities of the Arm, Shoulder, and Hand score improved significantly from 32 ± 12 before the operation to 5 ± 3 at the last postoperative visit. All patients showed statistically significant improvement in the range of motion and the grip strength of the involved wrist. The results of this study support the combined use of Kirschner wires and transarticular external fixation for fixation of a 1,2-intercompartmental supraretinacular artery-based vascular bone graft in the treatment of scaphoid nonunions. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  10. Radiographic healing and remodelling of cortical and cancellous bone grafts after rigid plate fixation

    International Nuclear Information System (INIS)

    Waris, P.; Karaharju, E.; Slaetis, P.; Paavolainen, P.

    1980-01-01

    Cortical and cancellous interposition grafts, with rigid plate fixation, in the tibiofibular bones of 130 rabbits were followed radiographically for one year. The cancellous grafts healed earlier, but by 12 weeks both graft types had been incorporated, the distal host-graft interface being the last to heal. Progressive cancellous transformation in both the graft and host bone led to an increased over-all bone diameter, a widened medullary canal and a thinned porotic wall. (Auth.)

  11. A different and safe method of split thickness skin graft fixation: medical honey application.

    Science.gov (United States)

    Emsen, Ilteris Murat

    2007-09-01

    Honey has been used for medicinal purposes since ancient times. Its antibacterial effects have been established during the past few decades. Still, modern medical practitioners hesitate to apply honey for local treatment of wounds. This may be because of the expected messiness of such local application. Hence, if honey is to be used for medicinal purposes, it has to meet certain criteria. The authors evaluated its use for the split thickness skin graft fixation because of its adhesive and other beneficial effects in 11 patients. No complications such as graft loss, infection, and graft rejection were seen. Based on these results, the authors advised honey as a new agent for split thickness skin graft fixation. In recent years there has been a renewed interest in honey wound management. There are a range of regulated wound care products that contain honey available on the Drug Tariff. This article addresses key issues associated with the use of honey, outlining how it may be best used, in which methods of split thickness skin graft fixations it may be used, and what clinical outcomes may be anticipated. For this reason, 11 patients who underwent different diagnosis were included in this study. In all the patients same medical honey was used for the fixation of the skin graft. No graft loss was seen during both the first dressing and the last view of the grafted areas. As a result, it has been shown that honey is also a very effective agent for split thickness skin graft fixations. Because it is a natural agent, it can be easily used in all skin graft operation for the fixation of the split thickness skin grafts.

  12. Honey: A Skin Graft Fixator Convenient for Both Patient and Surgeon.

    Science.gov (United States)

    Maghsoudi, Hemmat; Moradi, Sohrab

    2015-12-01

    Skin grafts can be used effectively to cover burn injuries. A critical element of this treatment is the adherence of the graft to the wound bed. Honey has been shown to increase the adherence of skin grafts to wound beds and have antibacterial and anti-inflammatory effects and increase healing rate of wounds. We therefore devised a clinical trial to determine the effect of honey on skin graft fixation in burn injuries. Sixty patients were included in this study (in 30 patients, graft was fixed with medical honey, and in 30 patients, it was fixed with dressing or suturing). All patients in two groups were evaluated for infection, graft loss, graft contraction, severity of pain, and need for re-operation. The most common cause of burn was kerosene. Honey significantly decreased infection rate on fifth day and reduced the patient pain. The mean hospital stay was shorter in honey group. Contraction of graft was significantly less in honey group. Honey has strong adhesive properties for skin graft fixation. Medical honey is a natural material, not synthetic. For this reason, we can advise the application of medical honey for the fixation of split thickness skin graft.

  13. 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.

  14. Honey: A Skin Graft Fixator Convenient for Both Patient and Surgeon

    OpenAIRE

    Maghsoudi, Hemmat; Moradi, Sohrab

    2014-01-01

    Skin grafts can be used effectively to cover burn injuries. A critical element of this treatment is the adherence of the graft to the wound bed. Honey has been shown to increase the adherence of skin grafts to wound beds and have antibacterial and anti-inflammatory effects and increase healing rate of wounds. We therefore devised a clinical trial to determine the effect of honey on skin graft fixation in burn injuries. Sixty patients were included in this study (in 30 patients, graft was fixe...

  15. 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.

  16. MRI of broken bioabsorbable crosspin fixation in hamstring graft reconstruction of the anterior cruciate ligament

    International Nuclear Information System (INIS)

    Bakhru, Prashant; Park, Brian; Umans, Hilary; DiFelice, Gregory S.; Tobin, Keith

    2011-01-01

    To report seven cases of broken bioabsorbable femoral crosspins identified by MRI in evaluation of hamstring grafts of the anterior cruciate ligament. Seven cases of broken bioabsorbable crosspins utilized in femoral fixation of ACL hamstring grafts were identified prospectively and retrospectively from our PACs database during a period from 9/1/08 to 8/31/09. All imaging was performed using 1.5 or 3.0 Tesla MRI and were evaluated for T2 signal within and surrounding the crosspin, osteolysis surrounding the fragments, displacement of fragments, and graft integrity. Time from surgery was also recorded. Seven cases of hamstring grafts with broken bioabsorbable crosspins were imaged 4 months to 3 years following grafting. There was osteolysis surrounding the crosspin in all but one case in which the graft was intact but a pin fragment was displaced into the joint. One graft failed due to aseptic foreign-body reaction to the fixation with aggressive osteolysis at 9 months post surgery. In the remaining five, the ACL graft was either completely torn, partially torn, lax, or degenerative and frayed. Of these, the crosspins were broken and angulated with osteolysis surrounding the apex of the angulated fragment or demonstrated lateral extrusion of the peripheral fragment. Bioabsorbable crosspins utilized in femoral fixation of hamstring graft reconstruction of the ACL may become fractured. While the natural history of osteo-integration of these devices as demonstrated by MRI has not been defined, osteolysis surrounding the fragments, extrusion or displacement of the fragments, and graft laxity or failure would suggest that these are abnormal findings that should be reported. (orig.)

  17. MRI of broken bioabsorbable crosspin fixation in hamstring graft reconstruction of the anterior cruciate ligament

    Energy Technology Data Exchange (ETDEWEB)

    Bakhru, Prashant [Department of Radiology Jacobi Medical Center, Bronx, NY (United States); Park, Brian [Albert Einstein College of Medicine, Bronx, NY (United States); Umans, Hilary [Department of Radiology Jacobi Medical Center, Bronx, NY (United States); Lenox Hill Radiology and Imaging Associates, P.C., New York, NY (United States); DiFelice, Gregory S. [Hospital for Special Surgery, New York, NY (United States); Tobin, Keith [Lenox Hill Radiology and Imaging Associates, P.C., New York, NY (United States)

    2011-06-15

    To report seven cases of broken bioabsorbable femoral crosspins identified by MRI in evaluation of hamstring grafts of the anterior cruciate ligament. Seven cases of broken bioabsorbable crosspins utilized in femoral fixation of ACL hamstring grafts were identified prospectively and retrospectively from our PACs database during a period from 9/1/08 to 8/31/09. All imaging was performed using 1.5 or 3.0 Tesla MRI and were evaluated for T2 signal within and surrounding the crosspin, osteolysis surrounding the fragments, displacement of fragments, and graft integrity. Time from surgery was also recorded. Seven cases of hamstring grafts with broken bioabsorbable crosspins were imaged 4 months to 3 years following grafting. There was osteolysis surrounding the crosspin in all but one case in which the graft was intact but a pin fragment was displaced into the joint. One graft failed due to aseptic foreign-body reaction to the fixation with aggressive osteolysis at 9 months post surgery. In the remaining five, the ACL graft was either completely torn, partially torn, lax, or degenerative and frayed. Of these, the crosspins were broken and angulated with osteolysis surrounding the apex of the angulated fragment or demonstrated lateral extrusion of the peripheral fragment. Bioabsorbable crosspins utilized in femoral fixation of hamstring graft reconstruction of the ACL may become fractured. While the natural history of osteo-integration of these devices as demonstrated by MRI has not been defined, osteolysis surrounding the fragments, extrusion or displacement of the fragments, and graft laxity or failure would suggest that these are abnormal findings that should be reported. (orig.)

  18. An External Wire Frame Fixation Method of Skin Grafting for Burn Reconstruction.

    Science.gov (United States)

    Yoshino, Yukiko; Ueda, Hyakuzoh; Ono, Simpei; Ogawa, Rei

    2017-06-28

    The skin graft is a prevalent reconstructive method for burn injuries. We have been applying external wire frame fixation methods in combination with skin grafts since 1986 and have experienced better outcomes in percentage of successful graft take. The overall purpose of this method was to further secure skin graft adherence to wound beds in hard to stabilize areas. There are also location-specific benefits to this technique such as eliminating the need of tarsorrhaphy in periorbital area, allowing immediate food intake after surgery in perioral area, and performing less invasive fixing methods in digits, and so on. The purpose of this study was to clarify its benefits and applicable locations. We reviewed 22 postburn patients with skin graft reconstructions using the external wire frame method at our institution from December 2012 through September 2016. Details of the surgical technique and individual reports are also discussed. Of the 22 cases, 15 (68%) were split-thickness skin grafts and 7 (32%) were full-thickness skin grafts. Five cases (23%) involved periorbital reconstruction, 5 (23%) involved perioral reconstruction, 2 (9%) involved lower limb reconstruction, and 10 (45%) involved digital reconstruction. Complete (100%) survival of the skin graft was attained in all cases. No signs of complication were observed. With 30 years of experiences all combined, we have summarized fail-proof recommendations to a successful graft survival with an emphasis on the locations of its application.

  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. The effect of infection and lag screw fixation on the union of membranous bone grafts in a rabbit model.

    Science.gov (United States)

    Fialkov, J A; Phillips, J H; Walmsley, S L

    1994-03-01

    Infection complicating craniofacial procedures contributes significantly to patient morbidity and health care costs. The role of fixation materials in this setting remains unclear. As foreign material, does fixation hardware increase patients' susceptibility to developing postoperative infection? Furthermore, once infection is established, should fixation hardware be removed? To answer these questions, we performed an onlay membranous bone grafting procedure to the mandible in 94 New Zealand White rabbits, applied lag-screw fixation in half the animals, and inoculated the wounds with different bacterial doses. We quantified the differential rates of infection and rates of graft union in the presence of infection. The infection rates for the rigidly fixated group were not significantly different from the rates for the nonfixated group for a range of bacterial inoculum doses. There was no significant difference in the rates of resolution of infection and sepsis between the two groups. Gross and histologic assessments revealed a significantly lower union rate for infected grafts when compared with uninfected grafts. Furthermore, grafts rigidly fixated with a lag screw showed a higher rate of union when compared with nonfixated grafts in the presence of infection. In the absence of infection, the union rates for fixated and nonfixated groups did not differ significantly. While fixation hardware has been cited as a risk factor for postoperative infection, we were unable to show that lag-screw fixation contributes to this risk. Although infection impaired the union of membranous bone grafts to the recipient mandible, fixation of the grafts with a lag screw significantly decreased this deleterious effect of infection.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. 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

    We studied the results of 16 consecutive midshaft clavicular nonunions operated on at the Shoulder and Elbow Clinic during the period from 1990 to 1993. All patients were treated with rigid 3.5 mm plate fixation and autologous cancellous bone grafting. Union of the fractures was achieved in all...... except one case, with a reconstruction ratio (restoration of bone length) of 0.96 (range 0.88 to 1.03). At follow-up 12 of 16 patients had returned to their preinjury activity level and according to the Constant score had obtained an excellent result. Two patients were graded as good, one as fair......, 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...

  2. Skin graft fixation in severe burns: use of topical negative pressure.

    Science.gov (United States)

    Kamolz, L P; Lumenta, D B; Parvizi, D; Wiedner, M; Justich, I; Keck, M; Pfurtscheller, K; Schintler, M

    2014-09-30

    Over the last 50 years, the evolution of burn care has led to a significant decrease in mortality. The biggest impact on survival has been the change in the approach to burn surgery. Early excision and grafting has become a standard of care for the majority of patients with deep burns; the survival of a given patient suffering from major burns is invariably linked to the take rate and survival of skin grafts. The application of topical negative pressure (TNP) therapy devices has demonstrated improved graft take in comparison to conventional dressing methods alone. The aim of this study was to analyze the impact of TNP therapy on skin graft fixation in large burns. In all patients, we applied TNP dressings covering a %TBSA of >25. The following parameters were recorded and documented using BurnCase 3D: age, gender, %TBSA, burn depth, hospital length-of-stay, Baux score, survival, as well as duration and incidence of TNP dressings. After a burn depth adapted wound debridement, coverage was simultaneously performed using split-thickness skin grafts, which were fixed with staples and covered with fatty gauzes and TNP foam. The TNP foam was again fixed with staples to prevent displacement and finally covered with the supplied transparent adhesive film. A continuous subatmospheric pressure between 75-120 mm Hg was applied (VAC®, KCI, Vienna, Austria). The first dressing change was performed on day 4. Thirty-six out of 37 patients, suffering from full thickness burns, were discharged with complete wound closure; only one patient succumbed to their injuries. The overall skin graft take rate was over 95%. In conclusion, we consider that split thickness skin graft fixation by TNP is an efficient method in major burns, notably in areas with irregular wound surfaces or subject to movement (e.g. joint proximity), and is worth considering for the treatment of aged patients.

  3. Closed reduction, internal fixation with quadratus femoris muscle pedicle bone grafting in displaced femoral neck fracture

    Directory of Open Access Journals (Sweden)

    Chaudhuri Sibaji

    2008-01-01

    Full Text Available Background: Management of femoral neck fracture is still considered as an unsolved problem. It is more evident in displaced fractures where this fracture is considered as some sort of vascular insult to the head of the femur. We have used closed reduction, internal fixation and quadratus femoris muscle pedicle bone grafting in fresh displaced femoral neck fractures. Materials and Methods: From April 1996 to December 2004 we operated 73 consecutive patients of displaced femoral neck fracture in the age group of 24 to 81 years, mean age being 54.6 years. The patients were operated within one week of injury, the mean delay being 3.6 days. Closed reduction internal fixation along with quadratus femoris muscle pedicle bone grafting was done in all cases. They were followed up for an average period of 5.6 years (range 2-11 years. Results: Results were assessed according to modified Harris Hip Scoring system and found to be excellent in 53, good in 12, fair in six and poor in two patients. Bony union occurred in 68 cases, no patient developed avascular necrosis (AVN till date. Conclusion: For fresh displaced femoral neck fracture in physiologically active patients closed reduction, internal fixation and quadratus femoris muscle pedicle bone grafting is a suitable option to secure union and prevent development of AVN.

  4. Knee stabiligy after ACL reconstruction through graft fixation in femoral tunnel: transfemoral pinning versus endobutton techniques

    Directory of Open Access Journals (Sweden)

    Tahmasebi MN

    2011-05-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: One of the most common orthopedic complaints is direct or indirect trauma to the knee with torn anterior cruciate ligament (ACL. Reconstruction of the torn ACL is emphatically offered in active individuals as by this operation, we prevent osteoarthritis, knee instability and injury to the meniscus. There are numerous methods for graft fixation in the femoral tunnel in ACL reconstruction. If the graft proves to be stable after the operation, patients would not complain of giving way knee joints. In this clinical trial, we compared transfemoral pinning with endobutton fixation of hamstring graft in arthroscopic ACL reconstruction by examining knee stability and use of other relevant functional tests. "n"nMethods : Fourteen Patients who had undergone arthroscopic ACL reconstruction in Shariati Hospital during the years 2008-2009 and were being followed up were evaluated at least 15 months post-operatively by physical examination and the use of an arthrometer made by the Faculty of Mechanics of Sharif Technical University."n"nResults : The results showed that two out of seven patients in which their ACL had been reconstructed by hamstring graft fixation by endobutton technique, and

  5. Surgical outcome of anterior decompression, grafting and fixation in caries of dorsolumbar spine

    International Nuclear Information System (INIS)

    Wadd, H.I.

    2015-01-01

    To evaluate the surgical outcome of anterior decompression, grafting and fixation in tuberculosis of the dorsal and lumbar spine with compression over the neural tissue and neural deficit. Study Design: A case series. Place and Duration of Study: Department of Neurosurgery Unit-I, Lahore General Hospital, Lahore, from January 2008 to March 2012. Methodology: Patients with caries spine having compression over the thecal sac with neurological deficit and kyphosis were included in the study. Patients below 17 years and above 56 years of age; those with bed sores and unfit for anesthesia were excluded from the study. Complete blood picture with ESR, X-rays of chest and of the relevant spinal level, and MRI were done. All patients were treated with corpectomy, debridement, drainage of abscess and grafting followed by fixation with poly-axial screws and rods. All patients were assessed by ASIA Impairment Scale before and after surgery and with Bridwell grading after surgery. Results: Among 79 patients, 47 were males and 32 females. The mean age was 35.97 ± 8.8 years. The commonest level involved was the dorsolumbar junction (n=42, 53.16%). Lower limb power improved to ambulatory level in 60% of patients with complete paraplegia; recovery was excellent in patients with partial weakness; only 2 patients (2.53%) deteriorated to a lower grade. There was no postoperative mortality. One patient had long ICU stay due to lung injury. Conclusion: Corpectomy followed by grafting and fixation is safe and effective procedure for dorsolumbar spinal caries. Even those patients presenting with complete paraplegia showed improvement in motor power to ambulatory level and those who had partial deficit showed excellent improvement. (author)

  6. Biomechanical properties of patellar and hamstring graft tibial fixation techniques in anterior cruciate ligament reconstruction: experimental study with roentgen stereometric analysis.

    Science.gov (United States)

    Adam, Frank; Pape, Dietrich; Schiel, Karin; Steimer, Oliver; Kohn, Dieter; Rupp, Stefan

    2004-01-01

    Reliable fixation of the soft hamstring grafts in ACL reconstruction has been reported as problematic. The biomechanical properties of patellar tendon (PT) grafts fixed with biodegradable screws (PTBS) are superior compared to quadrupled hamstring grafts fixed with BioScrew (HBS) or Suture-Disc fixation (HSD). Controlled laboratory study with roentgen stereometric analysis (RSA). Ten porcine specimens were prepared for each group. In the PT group, the bone plugs were fixed with a 7 x 25 mm BioScrew. In the hamstring group, four-stranded tendon grafts were anchored within a tibial tunnel of 8 mm diameter either with a 7 x 25 mm BioScrew or eight polyester sutures knotted over a Suture-Disc. The grafts were loaded stepwise, and micromotion of the graft inside the tibial tunnel was measured with RSA. Hamstring grafts failed at lower loads (HBS: 536 N, HSD 445 N) than the PTBS grafts (658 N). Stiffness in the PTBS group was much greater compared to the hamstring groups (3500 N/mm versus HBS = 517 N/mm and HSD = 111 N/mm). Irreversible graft motion after graft loading with 200 N was measured at 0.03 mm (PTBS), 0.38mm (HBS), and 1.85mm (HSD). Elasticity for the HSD fixation was measured at 0.67 mm at 100 N and 1.32 mm at 200 N load. Hamstring graft fixation with BioScrew and Suture-Disc displayed less stiffness and early graft motion compared to PTBS fixation. Screw fixation of tendon grafts is superior to Suture-Disc fixation with linkage material since it offers greater stiffness and less graft motion inside the tibial tunnel. Our results revealed graft motion for hamstring fixation with screw or linkage material at loads that occur during rehabilitation. This, in turn, may lead to graft laxity.

  7. Early tension loss in an anterior cruciate ligament graft. A cadaver study of four tibial fixation devices.

    Science.gov (United States)

    Grover, Dustin M; Howell, Stephen M; Hull, Maury L

    2005-02-01

    The tensile force applied to an anterior cruciate ligament graft determines the maximal anterior translation; however, it is unknown whether the tensile force is transferred to the intra-articular portion of the graft and whether the intra-articular tension and maximal anterior translation are maintained shortly after ligament reconstruction. Ten cadaveric knees were reconstructed with a double-looped tendon graft. The graft was looped through a femoral fixation transducer that measured the resultant force on the proximal end of the graft. A pneumatic cylinder applied a tensile force of 110 N to the graft exiting the tibial tunnel with the knee in full extension. The graft was fixed sequentially with four tibial fixation devices (a spiked metal washer, double staples, a bioabsorbable interference screw, and a WasherLoc). Three cyclic loading treatments designed to conservatively load the graft and its fixation were applied. The combined loss in intra-articular graft tension from friction, insertion of the tibial fixation device, and three cyclic loading treatments was 50% for the spiked washer (p = 0.0004), 100% for the double staples (p < 0.0001), 64% for the interference screw (p = 0.0001), and 56% for the WasherLoc (p < 0.0001). The tension loss caused an increase in the maximal anterior translation from that of the intact knee of 2.0 mm for the spiked washer (p = 0.005), 7.8 mm for the double staples (p < 0.0001), 2.7 mm for the interference screw (p = 0.001), and 2.1 mm for the WasherLoc (p < 0.0001). The tensile force applied to a soft-tissue anterior cruciate ligament graft is not transferred intra-articularly and is not maintained during graft fixation. The loss in tension is caused by friction in the tibial tunnel and wrapping the graft around the shank of the screw of the spiked washer, insertion of the tibial fixation device, and cyclical loading of the knee. The amount of tension loss is sufficient to increase the maximal anterior translation.

  8. The effect of infection and lag screw fixation on revascularization and new bone deposition in membranous bone grafts in a rabbit model.

    Science.gov (United States)

    Fialkov, J A; Phillips, J H; Walmsley, S L; Morava-Protzner, I

    1996-08-01

    We have suggested that rigid fixation of membranous bone grafts in the presence of infection may improve graft-recipient bone union by facilitating graft revascularzation. To test this hypothesis, we grafted autogenous membranous bone grafts to the mandibles of 94 New Zealand White rabbits. Lag screw fixation was applied in half the animals. The wounds were inoculated with a range of Staphylococcus aureus doses. Infected and noninfected rabbits were injected weekly over a 5-week course with fluorescein bone markers and with a marker of vascular endothelium (procion red) just prior to sacrifice. Revascularization and new bone deposition in the grafts were then quantified histologically for the 75 rabbits available for data collection. Infection decreased the amount of graft revascularized and the amount of new bone deposited for both rigidly fixated and nonfixated grafts. Grafts fixated with a lag screw showed a greater amount of revascularization and new bone deposition in the presence and absence of infection when compared with nonfixated grafts, supporting the hypothesis that rigid fixation of membranous bone grafts in the presence of infection may promote graft survival and union by improving revascularization and osteogenesis within the graft.

  9. 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

  10. Ununited fracture neck of femur treated with closed reduction and internal fixation with cancellous screw and fibular strut graft

    Directory of Open Access Journals (Sweden)

    Singh Daria

    2006-01-01

    Full Text Available Background: Ununited fracture neck of femur in young adults has been tackled in various ways. Methods: Twenty five patients of ununited fracture neck of femur in age group 21-55 years were treated by closed reduction, cancellous screw fixation and fibular strut graft and followed up for 2-6 years. Time gap between injury and operation was 6 weeks to 58 weeks. Five cases were previously fixed with various fixation devices. Results: Osseous union was achieved in 24 cases with average time of 18.16 weeks. Main complication encountered in follow-up was avascular necrosis of femoral head, others were joint stiffness and shortening. Functional end results were good to excellent in 24 cases. Conclusion: Closed reduction with internal fixation by cancellous screw and fibular strut grafting is easy and useful procedure.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    Pendse Aniruddha

    2006-01-01

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

  13. Evaluating different closed loop graft preparation technique for tibial suspensory fixation in ACL reconstruction using TightRope™

    Directory of Open Access Journals (Sweden)

    Takahisa Sasho

    2018-04-01

    Full Text Available In most anterior cruciate ligament (ACL reconstructions, grafts are fixed to the femoral side first followed by the tibial side. Various techniques have been reported to achieve optimal tension on the grafts, but once the grafts are fixed it is difficult to adjust graft tension further. To enable post fixation tension control we have invented a new graft configuration using an adjustable loop-device (TightRopeTM, Arthrex, FL, USA on the tibial side. In this paper, biomechanical properties of this configuration using soft tissue were examined in terms of graft diameter and various suture techniques (referred to as base suture to make a closed circle to support TightRopeTM.Two experiments were conducted under different conditions. In each experiment, cyclic load, followed by a pull-to-failure load, was applied to the grafts and elongation and failure mode were recorded. (1 To evaluate the effects of diameter, 5.0 or 6.0 mm grafts were prepared by a single locking loop stitch as the base suture (SLL5, SLL6. (2 To evaluate different base sutures, 5.0 mm tendons were used, and grafts were prepared using five kinds of base sutures (SLL, ZLL: zigzag locking loop, DZLL: double zigzag locking loop, DK: double Krackow, DK w/o TR: double Krackow without TightRopeTM. In the first experiment, tearing was observed in 2 of 6 cases in the SLL5 test group, whereas no tearing was observed with SLL6. In the second experiment, no tearing was observed with DZLL or DK. Elongation was smaller in these two groups compared to the other groups. Mechanical strength decreases with a smaller graft diameter. Biomechanical properties differed with different base sutures and, among them, the double-zigzag-suture stitch and double Krackow provided less elongation and higher ultimate load in this graft configuration.

  14. External wire-frame fixation of digital skin grafts: a non-invasive alternative to the K-wire insertion method.

    Science.gov (United States)

    Huang, Chenyu; Ogawa, Rei; Hyakusoku, Hiko

    2014-08-01

    The current skin graft fixation methods for digits, including the Kirschner wire insertion technique, can be limited by inadequate or excessive fixation and complications such as infection or secondary injuries. Therefore, the external wire-frame fixation method was invented and used for skin grafting of digits. This study aimed to investigate external wire-frame fixation of digital skin grafts as a non-invasive alternative to the K-wire insertion method. In 2005-2012, 15 patients with burn scar contractures on the hand digits received a skin graft that was then fixed with an external wire frame. The intra-operative time needed to make the wire frame, the postoperative time to frame and suture removal, the graft survival rate, the effect of contracture release and the complications were recorded. In all cases, the contracture release was 100%. The complete graft survival rate was 98.6%. Four patients had epithelial necrosis in wire-frame fixation is simple, minimally invasive and a custom-made technique for skin grafting of the fingers. It was designed for its potential benefits and the decreased risk it poses to patients with scar contractures on their fingers. It can be implemented in three phases of grafting, does not affect the epiphyseal line or subsequent finger growth and is suitable for children with multi-digit involvement. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  15. Fixation of split-thickness skin graft using fast-clotting fibrin glue containing undiluted high-concentration thrombin or sutures: a comparison study.

    Science.gov (United States)

    Han, Hyun Ho; Jun, Daiwon; Moon, Suk-Ho; Kang, In Sook; Kim, Min Cheol

    2016-01-01

    For skin defects caused by full-thickness burns, trauma, or tumor tissue excision, skin grafting is one of the most convenient and useful treatment methods. In this situation, graft fixation is important in skin grafting. This study was performed to compare the effectiveness of skin graft fixation between high-concentration fibrin sealant and sutures. There have been numerous studies using fibrin sealant for graft fixation, but they utilized slow-clotting fibrin sealant containing less than 10 IU/mL thrombin. Twenty-five patients underwent split-thickness skin grafting using fast-clotting fibrin sealant containing 400 IU/mL thrombin, while 30 patients underwent grafting using sutures. Rates of hematoma/seroma formation, graft dislocation, graft necrosis, and graft take were investigated postoperatively. The graft surface area was calculated using Image J software (National Institutes of Health, Bethesda, MD, USA). After 5 days, rates of hematoma/seroma formation and graft dislocation were 7.84 and 1.29% in group I, and 9.55 and 1.45% in group II, respectively. After 30 days, rates of graft necrosis and graft take were 1.86 and 98.14% in group I, and 4.65 and 95.35% in group II. Undiluted fibrin sealant showed significantly superior results for all rates ( p  < 0.05) except graft dislocation. When high-concentration fast-clotting fibrin sealant was applied to skin grafts without dilution, no difficulty was experienced during surgery. Sealant showed superior results compared with sutures and had an excellent graft take rate. II.

  16. Fixation methods in mandibular reconstruction using fibula grafts: a comparative study into the relative strength of three different types of osteosynthesis

    NARCIS (Netherlands)

    Strackee, S. D.; Kroon, F. H.; Bos, K. E.

    2001-01-01

    Bone staples made of a nickel titanium alloy exert dynamic compression, require little dissection, and may provide an alternative to conventional fixation in mandibular reconstruction with a free vascularized fibula graft. To evaluate its stability relative to conventional methods of fixation with

  17. [Treatment of thoracolumbar burst fracture with lateral anterior decompression, internal fixation with Ventrofix and bone graft with titanic mesh].

    Science.gov (United States)

    Zhang, Shi-min; Zhang, Zhao-jie; Liu, Yu-zhang; Zhang, Lu-tang; Li, Xing

    2011-11-01

    To discuss the efficacy of lateral anterior decompression, internal fixation with Ventrofix and bone graft with titanic mesh in the treatment of severe thoracolumbar burst fracture. From January 2008 to January 2010, 21 patients with severe thoracolumbar burst fracture were treated with lateral anterior decompression, internal fixation with Ventrofix, bone graft with titanic mesh. There were 15 males and 6 females, ranging in age from 21 to 46 years with an average of 32.2 years. Segment of fracture: 3 cases were in T11, 6 cases in T12, 7 cases in L1, 5 cases in L2. The mean kyphosis angle was 20.1 degrees and loading of fracture was 7.8 scores. Twenty-one cases accompany with incomplete paralysis. Nerves functions were observed according to Frankel grade; correction and maintain of kyphosis angle were observed by X-rays and CT. All the patients were followed up from 12 to 34 months with an average of 18.5 years. Postoperative complication including injury of pleura in 1 case, dynamic ileus in 2 cases, ilioinguinal nerve injury in 1 case, faulty union of wound in 1 case. All the above complications got recovery after symptomatic treatment. The mean kyphosis angle in fusional segment were 4.2 degrees and the rate of correction was 79%. Nerves functions of all patients got improvement and no internal fixation fail, kyphosis angle obviously lost, titanium mesh shifting, loosening and breakage of screw were found at final follow-up. Lateral anterior decompression, bone graft with titanic mesh, internal fixation with Ventrofix is an idea technique for severe thoracolumber burst fracture, but the method can not be used for patient with severity osteoporosis.

  18. Mechanical Biological Treatment

    DEFF Research Database (Denmark)

    Bilitewski, B-; Oros, Christiane; Christensen, Thomas Højlund

    2011-01-01

    The basic processes and technologies of composting and anaerobic digestion, as described in the previous chapters, are usually used for specific or source-separated organic waste flows. However, in the 1990s mechanical biological waste treatment technologies (MBT) were developed for unsorted...... or residual waste (after some recyclables removed at the source). The concept was originally to reduce the amount of waste going to landfill, but MBT technologies are today also seen as plants recovering fuel as well as material fractions. As the name suggests the technology combines mechanical treatment...... technologies (screens, sieves, magnets, etc.) with biological technologies (composting, anaerobic digestion). Two main technologies are available: Mechanical biological pretreatment (MBP), which first removes an RDF fraction and then biologically treats the remaining waste before most of it is landfilled...

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

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2007-01-01

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

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

    Directory of Open Access Journals (Sweden)

    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

  1. A Newly‑devised Technique for the Fixation of Mesh Skin Graft

    African Journals Online (AJOL)

    went skin graft using this technique. The ages ranged from. 9 months to 86 years (mean = 62.3 years). The skin defects included two burn ulcers, two decubitus, and 10 chronic leg ulcers. The size of the defects ranged from 20 cm2 to. 210 cm2. All grafts were accepted without complications. A 72-year-old man with a chronic ...

  2. Arthroscopic Latarjet Techniques: Graft and Fixation Positioning Assessed With 2-Dimensional Computed Tomography Is Not Equivalent With Standard Open Technique.

    Science.gov (United States)

    Neyton, Lionel; Barth, Johannes; Nourissat, Geoffroy; Métais, Pierre; Boileau, Pascal; Walch, Gilles; Lafosse, Laurent

    2018-05-19

    To analyze graft and fixation (screw and EndoButton) positioning after the arthroscopic Latarjet technique with 2-dimensional computed tomography (CT) and to compare it with the open technique. We performed a retrospective multicenter study (March 2013 to June 2014). The inclusion criteria included patients with recurrent anterior instability treated with the Latarjet procedure. The exclusion criterion was the absence of a postoperative CT scan. The positions of the hardware, the positions of the grafts in the axial and sagittal planes, and the dispersion of values (variability) were compared. The study included 208 patients (79 treated with open technique, 87 treated with arthroscopic Latarjet technique with screw fixation [arthro-screw], and 42 treated with arthroscopic Latarjet technique with EndoButton fixation [arthro-EndoButton]). The angulation of the screws was different in the open group versus the arthro-screw group (superior, 10.3° ± 0.7° vs 16.9° ± 1.0° [P open inferior screws (P = .003). In the axial plane (level of equator), the arthroscopic techniques resulted in lateral positions (arthro-screw, 1.5 ± 0.3 mm lateral [P open technique (0.9 ± 0.2 mm medial). At the level of 25% of the glenoid height, the arthroscopic techniques resulted in lateral positions (arthro-screw, 0.3 ± 0.3 mm lateral [P open technique (1.0 ± 0.2 mm medial). Higher variability was observed in the arthro-screw group. In the sagittal plane, the arthro-screw technique resulted in higher positions (55% ± 3% of graft below equator) and the arthro-EndoButton technique resulted in lower positions (82% ± 3%, P open technique (71% ± 2%). Variability was not different. This study shows that the position of the fixation devices and position of the bone graft with the arthroscopic techniques are statistically significantly different from those with the open technique with 2-dimensional CT assessment. In the sagittal plane, the arthro-screw technique provides the highest

  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. [The advantages in using cyanoacrylate glue over skin staples as a method of skin graft fixation in the pediatric burns population].

    Science.gov (United States)

    Curings, P; Vincent, P-L; Viard, R; Gir, P; Comparin, J-P; Voulliaume, D

    2017-11-23

    Local postoperative care and burn wound management can present with a certain degree of difficulty in the pediatric population. While the use of skin staples as a method of skin graft fixation is a well-known, rapid and simple method, their removal can be painful and may necessitate some sedation or even general anesthesia. We studied in this article the advantages and economic value of using the cyanoacrylate glue as a fixation method for skin grafts. A comparative study was carried out from 2012 to 2016. Hundred and eighteen infants with burns up to 5% of total body surface area were included in the study. Seventy-two infants had split thickness skin grafts fixed with skin staples. Forty-six infants had split thickness skin grafts fixed with cyanoacrylate glue. We compared the quality of graft, the sedation used during the first postoperative dressing, the length of hospital stay, the amount of glue used and the presence of complications. There is a difference between the two groups studied in terms of age and total burn surface area. The rate of graft take was 100% in both groups. The first postoperative dressing was carried out without the use of powerful analgesia in the cyanoacrylate group, while it was necessary to use general anesthesia in 64% of the skin staples group. The average length of stay in hospital after skin grafting was 4.9 days for the cyanoacrylate glue versus 6.5 days in the skin staples group. No complications were noted in the 2 groups. The use of cyanoacrylate glue allows rapid fixation of skin grafts and avoid general anesthesia for postoperative cares. Subsequently the length of hospital stay is reduced within 25%. The medico-economic value of glue protocol is highly significant compared to skin staples, while having similar good results and without significant problems. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. [EFFECTIVENESS COMPARISON OF CORACOCLAVICULAR LIGAMENT RECONSTRUCTION BETWEEN BY AUTOLOGOUS AND ALLOGENEIC TENDON GRAFTS COMBINED WITH HOOK PLATE FIXATION FOR TREATING ACROMIOCLAVICULAR JOINT DISLOCATION].

    Science.gov (United States)

    Yin, Fei; Sun, Zhenzhong; Wei, Xuming; Liu, Xueguang; Zhou, Ming; Zhuang, Yin; Song, Sheng

    2016-05-08

    To compare the effectiveness of coracoclavicular ligament reconstruction between by using autologous plantaris tendon graft combined with hook plate fixation and allogeneic tendon graft combined with hook plate fixation for treating acromiocavicular joint dislocation. Thirty-three patients with acromioclavicular joint dislocation who accorded with the inclusion criteria between January 2013 and June 2014 were assigned into 2 groups. The patients were treated with autologous plantaris tendon graft combined with hook plate fixation in group A ( n =17), and with allogeneic tendon graft combined with hook plate fixation in group B ( n =16). Thirteen-one patients was followed up more than 12 months (15 in group A and 16 in group B). There was no significant difference in gender, age, cause of injury, sides, time between injury and surgery, and type of dislocation ( P >0.05). The assessments included operation time, hospitalization time, hospitalization expenses, shoulder range of motion, gap of acromioclavicular, Constant-Murley scores, and visual analogue scale (VAS) for pain. The operation time of group A was significantly longer than that of group B, and the hospitalization expense was significantly lower than that of group B ( P 0.05). No redislocation of acromioclavicular joint and rejection reaction occurred during follow-up. At last follow-up, there was no significant difference in shoulder range of motion, Constant-Murley score, and VAS score between 2 groups ( P >0.05). Coracoclavicular ligament reconstruction by autologous plantaris tendon or allogeneic tendon graft combined with hook plate fixation for the treatment of acromioclavicular joint dislocation can achieve good effectiveness. The appropriate treatment should be chosen according to the patient's economic situation.

  6. What is the Effect of 90-Degree Double-Plate Fixation with Grafting on Healing of Humeral Shaft Non-unions

    Directory of Open Access Journals (Sweden)

    Mutlu Çobanoğlu

    2016-08-01

    Full Text Available Objective: Our aim was to investigate the clinical and radiological outcomes of double-plate fixation with grafting in the treatment of non-union of humeral shaft fractures. Materials and Methods: We performed a retrospective chart review of patients operated between 2006 and 2012 due to humeral shaft non-union. Patients undergoing surgery with double-plate fixation were included and those treated with external fixator, single plate, intramedullary nails and patients with pathological fractures and infected non-unions were excluded. Surgical intervention via anterolateral or posterior approach included radial nerve identification, decortication and reestablishment of medullary canal followed by compression plating with double-plate fixation and frequent application of autogenous grafts or allografts. Main outcome measures were success rate of non-union repair, rate of re-intervention and complications, range of motion, assessment of pain Visual analogue scale (VAS and function Disabilities of the arm, shoulder and hand (DASH and overall outcome Stewart-Hundley classification. Results: Ten patients were treated with double-plate fixation. The study group included six females and four males aged 36 to 70 years. Union was achieved within 4.5 and 8 months in all cases. The mean preoperative VAS score of 6.1 decreased to 2, postoperatively, with an associated decrease in the mean DASH score from 74.1 to 23.4. Excellent or good results were obtained in nine cases. There was no incidence of radial nerve palsy or infection. Conclusion: Our study provides level 4 evidence of the effectiveness of treating non-union fractures of the humeral shaft with double-plate fixation and grafting in providing good-to-excellent functional results and high union rate without any significant complication.

  7. Medial Patellofemoral Ligament Reconstruction: Impact of Knee Flexion Angle During Graft Fixation on Dynamic Patellofemoral Contact Pressure-A Biomechanical Study.

    Science.gov (United States)

    Lorbach, Olaf; Zumbansen, Nikolaus; Kieb, Matthias; Efe, Turgay; Pizanis, Antonius; Kohn, Dieter; Haupert, Alexander

    2018-04-01

    Objective evaluation of the optimal graft tension angle to fully restore patellofemoral contact pressure in reconstruction of the medial patellofemoral ligament (MPFL) in comparison to the native knee. Twelve cadaveric knee specimens were fixed in a custom-made fixation device. A sensitive pressure film (Tekscan) was fixed in the patellofemoral joint, and patellofemoral contact pressure was assessed during a dynamic flexion movement from 0° to 90°. The MPFL was cut and measurements were repeated. Reconstruction of the MPFL was performed with the gracilis tendon subsequently fixed in the femur at 15°, 30°, 45°, 60°, 75°, and 90° of knee flexion under controlled tension (2 N). The sequence of the flexion angles was alternated. Pressure measurements were repeated after every fixation of the graft. No significant differences were seen in the overall patellofemoral contact pressure compared to the native knee (P > .05). However, medial patellofemoral pressure showed a significant increased patellofemoral contact pressure after MPFL reconstruction at a knee flexion angle during graft fixation of 15° (P = .027), 45° (P = .050, P = .044), and 75° (P = .039). Moreover, proximal/distal patellofemoral contact pressure revealed a significantly reduced contact pressure at 15° (P = .003), 30° (P = .009), 45° (P = .025), 75° (P = .021), and 90° (P = .022) of flexion distal after MPFL reconstruction compared with the intact knee. Lateral patellofemoral contact pressure was significantly reduced in all performed reconstructions (P angle during graft fixation for MPFL reconstruction did not have a significant impact on the overall patellofemoral contact pressure. However, selective medial, proximal, distal, and lateral patellofemoral contact pressure was significantly altered for all reconstructions. Fixation of the MPFL graft at 60° of flexion was able to most closely restore patellofemoral contact pressure compared with the intact knee. Based on the

  8. 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...... contamination, and non union as well as the potential risk of disease transmission. Hydroxyapatite and collagen composites (HA/Collagen) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effects of newly developed HA/Collagen-composites with and without bone...... marrow aspirate (BMA) on enhancement of bone implant fixation. Method: Titanium alloy implants were inserted into bilateral femoral condyles of eight skeletally mature sheep, four implants per sheep. The implant had a circumferential gap of 2 mm. The gap was filled with: HA/Collagen; HA...

  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. Bioresorbable pins and interference screws for fixation of hamstring tendon grafts in anterior cruciate ligament reconstruction surgery: a randomized controlled trial.

    Science.gov (United States)

    Stengel, Dirk; Casper, Dirk; Bauwens, Kai; Ekkernkamp, Axel; Wich, Michael

    2009-09-01

    Biodegradable cross-pins have been shown to provide higher failure loads than do screws for fixation of hamstring tendons under laboratory conditions. To compare the clinical results of biodegradable pins (RigidFix) and interference screws (BioCryl) for fixation of hamstring grafts in arthroscopically assisted anterior cruciate ligament reconstruction. Study Design Randomized controlled trial; Level of evidence, 1. To test the hypothesis of a difference of 1.0 +/- 1.2 mm in anterior knee laxity between the two fixation options, 54 patients were randomly assigned to groups via a block randomization scheme and sealed envelopes. All patients underwent standardized hamstring graft reconstruction and had similar postoperative aftercare by an accelerated rehabilitation protocol. Measures assessed at baseline and after 1 and 2 years of follow-up included (1) the side-to-side difference in anterior laxity (KT-1000 arthrometer), (2) Short Form 36 physical and mental component scores, and (3) the International Knee Documentation Committee form scores. After 1 and 2 years, 26 and 21 patients in the BioCryl group and 28 and 24 patients in the RigidFix group were available for follow-up examination. No significant difference was noted in instrumented anterior translation between BioCryl and RigidFix fixation: 1 year, 0.11 (95% CI, -0.60 to 0.82; P = .7537); 2 years, 0.33 (95% CI, -0.43 to 1.08 mm; P = .3849). Also, there were no significant differences in the mean physical and mental component scores and International Knee Documentation Committee form scores and in overall complication and surgical revision rates. A pin dislocation was classified as the sole procedure-specific serious adverse event. Bioresorbable pins do not provide better clinical results than do resorbable interference screws for hamstring graft fixation in anterior cruciate ligament reconstruction surgery.

  11. Grafting

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, J L [New South Wales Univ., Kensington (Australia). School of Chemistry

    1979-01-01

    The unique value of ionizing radiation for the initiation of grafting to backbone polymers is discussed. The principles of the technique are briefly reviewed. The conditions under which free radicals and ions participate in these reactions are examined. Examples of representative grafting processes are considered to illustrate where the technique can be of potential commercial value to a wide range of industries. The general principles of these grafting reactions are shown to be applicable to radiation induced rapid cure technology such as is provided by electron beam processing facilities. Grafting reactions initiated by UV are also treated and shown to be of importance because of the many similarities in properties of the ionizing radiation and UV systems, also the rapid industrial exploitation of EB and sensitized UV processing technology. Possible future trends in radiation grafting are outlined.

  12. 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

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

    Science.gov (United States)

    Elmengaard, Brian; Baas, Joergen; Jakobsen, Thomas; Kold, Soren; Jensen, Thomas B; Bechtold, Joan E; Soballe, Kjeld

    2017-02-01

    We previously introduced a manual surgical technique that makes small perforations (cracks) through the sclerotic bone shell that typically forms during the process of aseptic loosening ("crack" revision technique). Perforating just the shell (without violating the proximal cortex) can maintain overall bone continuity while allowing marrow and vascular elements to access the implant surface. Because many revisions require bone graft to fill defects, we wanted to determine if bone graft could further increase implant fixation beyond what we have experimentally shown with the crack technique alone. Also, because both titanium (Ti6Al4V) and hydroxyapatite (HA) implant surfaces are used in revisions, we also wanted to determine their relative effectiveness in this model. We hypothesized that both (1) allografted plasma-sprayed Ti6Al4V; and (2) allografted plasma-sprayed HA-coated implants inserted with a crack revision technique have better fixation compared with a noncrack revision technique in each case. Under approval from our Institutional Animal Care and Use Committee, a female canine animal model was used to evaluate the uncemented revision technique (crack, noncrack) using paired contralateral implants while implant surface (Ti6Al4V, HA) was qualitatively compared between the two (unpaired) series. All groups received bone allograft tightly packed around the implant. This revision model includes a cylindrical implant pistoning 500 μm in a 0.75-mm gap, with polyethylene particles, for 8 weeks. This engenders a bone and tissue response representative of the metaphyseal cancellous region of an aseptically loosened component. At 8 weeks, the original implants were revised and followed for an additional 4 weeks. Mechanical fixation was assessed by load, stiffness, and energy to failure when loaded in axial pushout. Histomorphometry was used to determine the amount and location of bone and fibrous tissue in the grafted gap. The grafted crack revision improved

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

    DEFF Research Database (Denmark)

    Babiker, Hassan

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

  15. Gradual digital lengthening with autologous bone graft and external fixation for correction of flail toe in a patient with Raynaud's disease.

    Science.gov (United States)

    Lamm, Bradley M; Ades, Joe K

    2009-01-01

    Iatrogenic flail toe is a complication of hammertoe surgery that occurs when an overaggressive resection of the proximal phalanx occurs. This can cause both functional and cosmetic concerns for the patient. We present a case report of the correction of a flail second toe in a patient with Raynaud's disease. The correction was achieved by means of gradual soft tissue lengthening with external fixation and an interposition autologous bone graft digital arthrodesis. After 5 months, this 2-stage procedure lengthened, stabilized, and restored the function of the toe. 4.

  16. 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.

  17. 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.

  18. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  19. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  1. The initial instability of cemented and non-cemented femoral stems fixated with a bone grafting technique

    NARCIS (Netherlands)

    Schreurs, B.W.; Huiskes, H.W.J.; Slooff, T.J.J.H.

    1994-01-01

    To reconstruct intramedullary bone stock in revision surgery of failed total hip arthroplasties, a method was developed using impacted trabecular bone grafts. In an in vitro model with femora of the goat, the initial stabilities of both cemented and non-cemented hydroxylapatite-coated stems in this

  2. Plate Fixation With Autogenous Calcaneal Dowel Grafting Proximal Fourth and Fifth Metatarsal Fractures: Technique and Case Series.

    Science.gov (United States)

    Seidenstricker, Chad L; Blahous, Edward G; Bouché, Richard T; Saxena, Amol

    Metaphyseal and proximal diaphyseal fractures of the lateral column metatarsals can have problems with healing. In particular, those involving the fifth metatarsal have been associated with a high nonunion rate with nonoperative treatment. Although intramedullary screw fixation results in a high union rate, delayed healing and complications can occur. We describe an innovative technique to treat both acute and chronic injuries involving the metatarsal base from the metaphysis to the proximal diaphyseal bone of the fourth and fifth metatarsals. The surgical technique involves evacuation of sclerotic bone at the fracture site, packing the fracture site with compact cancellous bone, and plate fixation. In our preliminary results, 4 patients displayed 100% radiographic union at a mean of 4.75 (range 4 to 6) weeks with no incidence of refracture, at a mean follow-up point of 3.5 (range 1 to 5) years. The early results with our small series suggest that this technique is a useful treatment choice for metaphyseal and proximal diaphyseal fractures of the fourth and fifth metatarsals. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Proximal Pole Scaphoid Nonunion Reconstruction With 1,2 Intercompartmental Supraretinacular Artery Vascularized Graft and Compression Screw Fixation.

    Science.gov (United States)

    Morris, Mark S; Zhu, Andy F; Ozer, Kagan; Lawton, Jeffrey N

    2018-02-06

    To review the incidence of union of patients with proximal pole scaphoid fracture nonunions treated using a 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) vascularized graft and a small compression screw. This is a retrospective case series of 12 patients. Calculations of the size of the proximal pole fragment relative to the total scaphoid were performed using posteroanterior view scaphoid radiographs with the wrist in ulnar deviation and flat on the cassette. Analyses were repeated 3 times per subject, and the average ratio of proximal pole fragment relative to the entire scaphoid was calculated. We reviewed medical records, radiographs, and computed tomography (CT) scans of these 12 patients. The CT scans that were performed after an average of 12 weeks were ultimately used to confirm union of the scaphoid fractures. One patient was unable to have a CT so was excluded from the final calculation. All 11 (100%) scaphoid fractures that were assessed by CT were found to be healed at the 12-week assessment point. The mean proximal pole fragment size was 18% (range, 7%-27%) of the entire scaphoid. The 1,2 ICSRA vascularized graft and compression screw was an effective treatment for patients with proximal pole scaphoid fractures. Therapeutic IV. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  4. A Novel Surgical Technique for Fixation of Recurrent Acromioclavicular Dislocations: AC Dog Bone Technique in Combination with Autogenous Semitendinosus Tendon Graft

    Directory of Open Access Journals (Sweden)

    Patrick Holweg

    2017-01-01

    Full Text Available Various surgical techniques have been described for the fixation of acromioclavicular (AC dislocations. However, recurrent dislocation is one of the main complications associated with the majority of these techniques. We report a case of postoperative AC joint redislocation. In order to overcome recurrent dislocation after revision surgery, a reconstruction of the conoid and trapezoid ligament with the use of a free tendon graft in combination with a FiberTape was provided within a novel surgical technique. After 12 months, the patient was very satisfied with the functional outcome. The patient achieved excellent results in the Constant (98 points, SPADI (0 points, and QuickDASH score (0 points. The described technique results in an anatomic reconstruction of the AC joint. The nonrigid nature of the intervention seems to restore the normal arthrokinematics by reconstructing the coracoclavicular ligaments with an autograft which is then protected by the AC Dog Bone artificial ligaments during the healing period. The arthroscopic approach to the AC joint with minimal exposure reduces the risks and complications of the intervention. This is the first case in literature that utilizes the artificial dog bone ligament securing the autograft in an anatomic AC reconstruction.

  5. Comparison between Conventional Mechanical Fixation and Use of Autologous Platelet Rich Plasma (PRP) in Wound Beds Prior to Resurfacing with Split Thickness Skin Graft.

    Science.gov (United States)

    P Waiker, Veena; Shivalingappa, Shanthakumar

    2015-01-01

    Platelet rich plasma is known for its hemostatic, adhesive and healing properties in view of the multiple growth factors released from the platelets to the site of wound. The primary objective of this study was to use autologous platelet rich plasma (PRP) in wound beds for anchorage of skin grafts instead of conventional methods like sutures, staplers or glue. In a single center based randomized controlled prospective study of nine months duration, 200 patients with wounds were divided into two equal groups. Autologous PRP was applied on wound beds in PRP group and conventional methods like staples/sutures used to anchor the skin grafts in a control group. Instant graft adherence to wound bed was statistically significant in the PRP group. Time of first post-graft inspection was delayed, and hematoma, graft edema, discharge from graft site, frequency of dressings and duration of stay in plastic surgery unit were significantly less in the PRP group. Autologous PRP ensured instant skin graft adherence to wound bed in comparison to conventional methods of anchorage. Hence, we recommend the use of autologous PRP routinely on wounds prior to resurfacing to ensure the benefits of early healing.

  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. 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

  8. Vascularised Fibular Graft for a Radial Defect following Tumour ...

    African Journals Online (AJOL)

    HP

    The mass was located on the radial aspect of the distal right ... modification, internal or external fixation with bone grafting, structural grafts of ... Our index case report demonstrates that free vascularized fibular graft transfer is a feasible option ... structural support, the potential for graft hypertrophy, relative resistance to ...

  9. Skin graft

    Science.gov (United States)

    Skin transplant; Skin autografting; FTSG; STSG; Split thickness skin graft; Full thickness skin graft ... donor site. Most people who are having a skin graft have a split-thickness skin graft. This takes ...

  10. Direct landfill disposal versus Mechanical Biological Treatment (MBT

    Directory of Open Access Journals (Sweden)

    Kulhawik Katarzyna

    2016-09-01

    Full Text Available After the implementation of a new waste management system, in which recycling is the most dominating process, landfill disposal still appears to be the most popular method of waste management in Poland, in which waste undergoes gradual decomposition and the influence of climate conditions, for example, air and atmospheric fallout, leads to the production of leachate and biogas emissions, which contribute to continual threats to the natural environment and humans. The above-mentioned threats can be limited by applying suitable techniques of waste treatment before its disposal. A technology that is oriented to these aims is a mechanical biological treatment (MBT before disposal.

  11. The effect on implant fixation of soaking tricalcium phosphate granules in bisphosphonate

    DEFF Research Database (Denmark)

    Jakobsen, Thomas; Baas, Jørgen; Bechtold, Joan E

    2012-01-01

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

  12. The autologus graft of epithelial tissue culture

    Directory of Open Access Journals (Sweden)

    Minaee B

    1999-08-01

    Full Text Available With the intention of research about culture and autologus graft of epithelial tissue we used 4 french Albino Rabbits with an average age of 2 months. After reproduction on the support in EMEM (Eagle's Minimum Essential Medium we used this for graft after 4 weeks. This region which grafted total replaced. After fixation of this sample and passing them through various process, histological sections were prepared. These sections were stained with H & E and masson's trichrome and studied by light microscope. We succeeded in graft. We hope in the near future by using the method of epithelium tissue culture improving to treat burned patients.

  13. Fusion Surgery Required for Recurrent Pediatric Atlantoaxial Rotatory Fixation after Failure of Temporary Fixation with Instrumentation

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Matsuyama

    2017-01-01

    Full Text Available In cases of chronic irreducible and recurrent unstable atlantoaxial rotatory fixation (AARF, closed reduction and its maintenance are often unsuccessful, requiring surgical treatment. The purpose of the present report is to describe a rare case of pediatric AARF that required multiple treatments. A 6-year-old boy was diagnosed as having type 2 AARF. After conservative treatment, the patient was treated with temporary fixation surgery (C1-C2 Magerl without a bone graft in consideration of motion preservation after screw removal. AARF recurred after the screw removal and required fusion surgery (Magerl–Brooks with an iliac bone graft. Ultimately, bone union was achieved and the screws were removed 11 months after the surgery. We recommend surgeons be cautious when choosing temporary fixation surgery for AARF in small children. Further investigation is needed to determine the optimal time before screw removal.

  14. Skin Graft

    OpenAIRE

    Shimizu, Ruka; Kishi, Kazuo

    2012-01-01

    Skin graft is one of the most indispensable techniques in plastic surgery and dermatology. Skin grafts are used in a variety of clinical situations, such as traumatic wounds, defects after oncologic resection, burn reconstruction, scar contracture release, congenital skin deficiencies, hair restoration, vitiligo, and nipple-areola reconstruction. Skin grafts are generally avoided in the management of more complex wounds. Conditions with deep spaces and exposed bones normally require the use o...

  15. CSF coccidioides complement fixation

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003526.htm CSF coccidioides complement fixation test To use the sharing features on this page, please enable JavaScript. CSF coccidioides complement fixation is a test that checks ...

  16. 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.

  17. 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.

  18. 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.

  19. Pancreas grafts

    International Nuclear Information System (INIS)

    Hahn, D.; Buell, U.; Land, W.; Unertl, K.

    1981-01-01

    Perfusion studies with sup(99m)Tc-DTPA, which has hitherto been used routinely to investigate renal grafts, have also proved useful for monitoring the perfusion of pancreas grafts. A total perfusion failure is equally reliably demonstrable as in renal grafts. Quantitatively smaller perfusion alterations can be demonstrated by monitoring the course. It seems possible to differentiate the salivary edema of a rejection reaction, well known from animal experiments, with the help of other paramters (e.g. creatinine). Further clinical studies are however necessary to confirm these results. (orig.) [de

  20. Comparison of Monolateral External Fixation and Internal Fixation for Skeletal Stabilisation in the Management of Small Tibial Bone Defects following Successful Treatment of Chronic Osteomyelitis.

    Science.gov (United States)

    Wang, Yicun; Jiang, Hui; Deng, Zhantao; Jin, Jiewen; Meng, Jia; Wang, Jun; Zhao, Jianning; Sun, Guojing; Qian, Hongbo

    2017-01-01

    To compare the salvage rate and complication between internal fixation and external fixation in patients with small bone defects caused by chronic infectious osteomyelitis debridement. 125 patients with chronic infectious osteomyelitis of tibia fracture who underwent multiple irrigation, debridement procedure, and local/systemic antibiotics were enrolled. Bone defects, which were less than 4 cm, were treated with bone grafting using either internal fixation or monolateral external fixation. 12-month follow-up was conducted with an interval of 3 months to evaluate union of bone defect. Patients who underwent monolateral external fixation had higher body mass index and fasting blood glucose, longer time since injury, and larger bone defect compared with internal fixation. No significant difference was observed in incidence of complications (23.5% versus 19.3%), surgery time (156 ± 23 minutes versus 162 ± 21 minutes), and time to union (11.1 ± 3.0 months versus 10.9 ± 3.1 months) between external fixation and internal fixation. Internal fixation had no significant influence on the occurrence of postoperation complications after multivariate adjustment when compared with external fixation. Furthermore, patients who underwent internal fixation experienced higher level of daily living scales and lower level of anxiety. It was relatively safe to use internal fixation for stabilization in osteomyelitis patients whose bone defects were less than 4 cm and infection was well controlled.

  1. Kinetics of vein graft hyperplasia

    International Nuclear Information System (INIS)

    Zwolak, R.M.; Adams, M.C.; Clowes, A.W.

    1986-01-01

    Human aortocoronary vein grafts fail due to accelerated occlusive disease. The possibility that this is related to cellular hyperplasia was investigated in a rabbit model where kinetics of vein graft thickening, endothelial (EC) repair, and smooth muscle cell (SMC) proliferation were measured from 2 days to 24 weeks after implanting jugular vein segments in the carotid artery. Immediately after graft placement focal EC denudation was observed. These defects were repaired within 1 week and did not recur. By 4 weeks intimal area had increased 30 fold from 0.028 +/- 0.004 to 0.705 +/- 0.021 mm 2 , and a 24 weeks was 0.93 +/- 0.21 mm 2 . This response did not produce a reduction in graft lumen area. EC and SMC thymidine-labeling index were measured by en face and cross-section autoradiography after injection of 3 H-thymidine and perfusion fixation. Despite rapid EC surface repair EC labeling index remained elevated and only returned to normal levels at 12 weeks; SMC labeling was 10 fold greater than baseline even at 24 weeks (0.22% vs 0.02%). SMC mass demonstrated morphometrically increased between 2 and 12 weeks. Intimal thickening in vein grafts is due to SMC proliferation and develops after the EC layer has been restored. In contrast, intimal SMC proliferate in damaged arteries when the EC layer is absent and cease when the EC layer is regenerated

  2. Reconstrução do LCA com o uso dos tendões dos músculos flexores mediais do joelho e fixação femoral com o sistema de Rigidifix®: relato preliminar Anterior cruciate ligament reconstruction using double hamstrings tendon graft and the femoral fixation by Rigidifix®: preliminary Study

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Cury Faustino

    2004-12-01

    Full Text Available O autor descreve a técnica de reconstrução do LCA no tratamento das instabilidades anterior do joelho, utilizando os tendões dos músculos flexores mediais do joelho (semitendíneo e grácil, fixados no fêmur pelo sistema de Rigidfix®; e na tíbia, com parafuso de interferência absorvível, através de um estudo preliminar de 54 joelhos operados. Na avaliação final pela escala de Lysholm os pacientes evoluíram de 46 pontos no pré-operatório para 92 pontos no pós-operatório.The author describes the reconstruction technique of the anterior cruciate ligament reconstruction using the hamstrings tendon (semitendinosus and gracilis in the management of anterior instabilities of the knee joint. Rigidfix® system is used to fix the graft on the femur and an absorbable interference screw was used for tibial fixation in a preliminary study in 54 knees. The final evaluation based on Lysholm score showed an improvement from 46 (preoperative to 92 (postoperative.

  3. STUDY ON SPANNING EXTERNAL FIXATORS FOR PERIARTICULAR OPEN FRACTURES

    Directory of Open Access Journals (Sweden)

    Prasanth Maddila

    2017-04-01

    Full Text Available BACKGROUND Open fractures which occur close to any fracture need immobilisation for the soft tissues to heal. Some open fractures are even fixed with provisional fixations to maintain the alignment of the fractures. The provisional fixation needs to be augmented with external support, which can be given by spanning external fixators across a joint. MATERIALS AND METHODS Our study consists of 38 open fractures of the lower limbs, which are of Gustilo-Anderson’s type IIIB, an MT4 of AO-ASIF soft tissue injury classification essentially requiring open wound management as well as fracture fixation. Wound lavage and debridements are carried out till the soft tissues show granulations. The position in which joint is immobilised is functional and with access to open wound for dressings and inspection without any displacement of the fracture as well as creeping granulation tissue. RESULTS All the cases in our study are maintained with functional position till soft tissue cover is achieved and provisional fixation is done with definitive fixation after soft tissue cover with skin grafting. CONCLUSION Spanning external fixators are useful in maintaining functional positions as well as augmenting the provisional fixation of the compound fractures.

  4. 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

  5. Using negative pressure therapy for improving skin graft taking on genital area defects following Fournier gangrene.

    Science.gov (United States)

    Orhan, Erkan; Şenen, Dilek

    2017-09-01

    Fournier's gangrene is an infective necrotizing fasciitis of the perineal, genital and perianal regions. Treatment includes aggressive surgical debridement that often results in extensive loss of genital skin. Skin grafts may be used for reconstruction but skin grafting of the male genitalia is diffucult because the penis and scrotum are mobile and deformable. A variety of methods are used to secure skin graft to recipient beds. We used negative pressure therapy (NPT) to secure skin grafts and improve skin graft taking. We used negative pressure therapy for graft fixation in 13 male patients who underwent debridements with the indication of Fournier gangrene, and whose defects formed were reconstructed with grafts between January 2009, and January 2014. Information about age of the patients, sessions of negative pressure therapy applied before, and after reconstruction, duration of hospital stay, and graft losses during postoperative period were recorded. Median age of the patients was 56.15 (46-72) years. NPT was applied to patients for an average of 6.64 sessions (4-12) before and 1 sessions after graft reconstruction. Patients were hospitalized for an average of 26.7 (20-39) days. Any graft loss was not seen after NPT. Because of the peculiar anatomy of the genital region, anchoring of grafts is difficult so graft losses are often encountered. Use of NPT for ensuring graft fixation on the genital region prevents skin graft shearing.

  6. External fixation of tibial pilon fractures and fracture healing.

    Science.gov (United States)

    Ristiniemi, Jukka

    2007-06-01

    Distal tibial fractures are rare and difficult to treat because the bones are subcutaneous. External fixation is commonly used, but the method often results in delayed union. The aim of the present study was to find out the factors that affect fracture union in tibial pilon fractures. For this purpose, prospective data collection of tibial pilon fractures was carried out in 1998-2004, resulting in 159 fractures, of which 83 were treated with external fixation. Additionally, 23 open tibial fractures with significant > 3 cm bone defect that were treated with a staged method in 2000-2004 were retrospectively evaluated. The specific questions to be answered were: What are the risk factors for delayed union associated with two-ring hybrid external fixation? Does human recombinant BMP-7 accelerate healing? What is the role of temporary ankle-spanning external fixation? What is the healing potential of distal tibial bone loss treated with a staged method using antibiotic beads and subsequent autogenous cancellous grafting compared to other locations of the tibia? The following risk factors for delayed healing after external fixation were identified: post-reduction fracture gap of >3 mm and fixation of the associated fibula fracture. Fracture displacement could be better controlled with initial temporary external fixation than with early definitive fixation, but it had no significant effect on healing time, functional outcome or complication rate. Osteoinduction with rhBMP-7 was found to accelerate fracture healing and to shorten the sick leave. A staged method using antibiotic beads and subsequent autogenous cancellous grafting proved to be effective in the treatment of tibial bone loss. Healing potential of the bone loss in distal tibia was at least equally good as in other locations of the tibia.

  7. Free flap reconstructions of tibial fractures complicated after internal fixation.

    Science.gov (United States)

    Nieminen, H; Kuokkanen, H; Tukiainen, E; Asko-Seljavaara, S

    1995-04-01

    The cases of 15 patients are presented where microvascular soft-tissue reconstructions became necessary after internal fixation of tibial fractures. Primarily, seven of the fractures were closed. Eleven fractures had originally been treated by open reduction and internal fixation using plates and screws, and four by intramedullary nailing. All of the patients suffered from postoperative complications leading to exposure of the bone or fixation material. The internal fixation material was removed and radical revision of dead and infected tissue was carried out in all cases. Soft tissue reconstruction was performed using a free microvascular muscle flap (11 latissimus dorsi, three rectus abdominis, and one gracilis). In eight cases the nonunion of the fracture indicated external fixation. The microvascular reconstruction was successful in all 15 patients. In one case the recurrence of deep infection finally indicated a below-knee amputation. In another case, chronic infection with fistulation recurred postoperatively. After a mean follow-up of 26 months the soft tissue coverage was good in all the remaining 13 cases. All the fractures united. Microvascular free muscle flap reconstruction of the leg is regarded as a reliable method for salvaging legs with large soft-tissue defects or defects in the distal leg. If after internal fixation of the tibial fracture the osteosynthesis material or fracture is exposed, reconstruction of the soft-tissue can successfully be performed by free flap transfer. By radical revision, external fixation, bone grafting, and a free flap the healing of the fracture can be achieved.

  8. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  9. Soaking morselized allograft in bisphosphonate can impair implant fixation

    DEFF Research Database (Denmark)

    Jakobsen, Thomas; Baas, Jørgen; Bechtold, Joan E

    2007-01-01

    biomechanical implant fixation and graft incorporation. In 10 dogs, a pair of titanium implants surrounded by a 2.5-mm gap was inserted into the proximal part of each humerus during two separate surgeries to allow two observation periods. The gap was filled with impacted, morselized allograft soaked in either...... of implants was observed for 12 weeks and the second pair for 4 weeks. Implants were evaluated by histomorphometry and biomechanical pushout test. We found substantially decreased biomechanical implant fixation for all implants surrounded by impacted, morselized allograft that had been soaked in alendronate...

  10. Effectiveness of Fibrin Glue in Adherence of Skin Graft.

    Science.gov (United States)

    Reddy, Konda Sireesha; Chittoria, Ravi Kumar; Babu, Preethitha; Marimuthu, Senthil Kumaran; Kumar, Sudhanva Hemanth; Subbarayan, Elan Kumar; Chavan, Vinayak; Mohapatra, Devi Prasad; Sivakumar, Dinesh Kumar; Friji, M T

    2017-01-01

    Graft fixation is important for graft take. Fibrin glue has been proposed as an ideal material, because of its human origin and it provides firm adhesion in seconds or minutes. To evaluate the efficiency of fibrin glue, in increasing the take of skin graft. Assessment includes surgical time taken for graft fixation, haematoma/seroma formation, engraftment and wound closure by day 14. The study is an observational prospective study conducted in the Department of Plastic Surgery, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, from January 2016 to June 2016. Sixteen patients who underwent split skin grafting were assessed during the study period. Fibrin glue was used on the recipient bed before grafting. Better haemostasis and graft adhesion, with a significant reduction of surgical time, were noted. The safety profile of fibrin glue was excellent as indicated by the lack of any related serious adverse experiences. These findings demonstrate that it is safe and effective for attachment of skin grafts, with outcomes at least as good as conventional methods.

  11. Potential of development of the mechanical-biological waste treatment; Entwicklungspotenzial der Mechanisch-Biologischen Abfallbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Grundmann, Thomas; Balhar, Michael [ASA e.V., Ennigerloh (Germany); Abfallwirtschaftsgesellschaft des Kreises Warendorf mbH, Ennigerloh (Germany)

    2013-03-01

    The Consortium Material-Specific Waste Treatment eV (Ennigerloh, Federal Republic of Germany) is an association of plant operators having the opinion that an economic and ecologic waste treatment only can be guaranteed by material-specific processes permanently. Due to the specific treatment processes in plants with mechanical-biological waste treatment (MBA) material flows are resulting being available for the recycling or exploitation. Under this aspect, the authors of the contribution under consideration report on the development potential of the mechanical-biological waste treatment. The state of the art of the technology of mechanical-biological waste treatment in Germany as well as the contribution of this technology to the resource protection and climate protection are described. Further aspects of this contribution are the increase of the energy efficiency and reduction of emissions; further development of the efficient sorting technology; development of integrated total conceptions - MBA-sites as centres for the production of renewable energies.

  12. Bone Graft Alternatives

    Science.gov (United States)

    ... Spine Treatment Spondylolisthesis BLOG FIND A SPECIALIST Treatments Bone Graft Alternatives Patient Education Committee Patient Education Committee ... procedure such as spinal fusion. What Types of Bone Grafts are There? Bone grafts that are transplanted ...

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

    International Nuclear Information System (INIS)

    Kim, Jong Dae; Oh, Chae Youn; Kim, Cheol Sang

    2008-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-12-15

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

  15. Skin grafting in severely contracted socket with the use of ′Compo′

    Directory of Open Access Journals (Sweden)

    Betharia S

    1990-01-01

    Full Text Available The results of split thickness autologous skin grafting along with the use of a dental impression material (Compo, a thermoplastic substance are presented in a series of 11 patients of acquired, severely contracted, anophthalmic sockets. Only the fornix fixation sutures and the central tarsorrhaphy were employed for the proper placement of graft without the use of retention devices. Artificial eyes were successfully fitted and retained subsequently after 6 weeks of grafting.

  16. Can we improve fixation and outcomes? Use of bone substitutes.

    Science.gov (United States)

    Moroni, Antonio; Larsson, Sune; Hoang Kim, Amy; Gelsomini, Letizia; Giannoudis, Peter V

    2009-07-01

    Hip fractures secondary to osteoporosis are common in the elderly. Stabilizing these fractures until union is achieved is a challenge due to poor bone stock and insufficient purchase of the implant to the bone. The reported high rate of complications has prompted extensive research in the development of fixation techniques. Furthermore, manipulation of both the local fracture environment in terms of application of growth factors, scaffolds, and mesenchymal cells and the systemic administration of agents promoting bone formation and bone strength has been considered as a treatment option with promising results. There are only a few evidence-based studies reporting on fixation augmentation techniques. This article reports on the efficacy of bone graft substitutes for the fixation of hip fractures, in particular calcium phosphates, which have been used as granules, cements, and implant coatings.

  17. Flexible fixation and fracture healing

    DEFF Research Database (Denmark)

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

    2011-01-01

    , noncomminuted fractures. External fixation uses external bars for stabilization, whereas internal fixation is realized by subcutaneous placement of locking plates. Both of these "biologic" osteosynthesis methods allow a minimally invasive approach and do not compromise fracture hematoma and periosteal blood...

  18. Sacroiliac Screw Fixation

    NARCIS (Netherlands)

    E.W. van den Bosch

    2003-01-01

    textabstractThe aim of this thesis is to evaluate three major aspects of the use of sacroiliac screws in patients with unstable pelvic ring fractures: the optimal technique for sacroiliac screw fixation, the reliability of peroperative fluoroscopy and the late results. We focused on the questions

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    from the iliac crest. For both groups, mononuclear cells were isolated, and injected into a perfusion bioreactor (Millenium Biologix AG, Switzerland). Scaffold granules (Ø~900-1500 µm, ~88% porosity) in group 1, consisted of hydroxyapatite (HA, 70%) with β-tricalcium-phosphate (β-TCP, 30%) (Danish....... The superficial part was used for mechanical testing and micro-CT scanning, and the profound part for histomorphometry. Push-out tests were performed on an 858 Bionix MTS hydraulic materials testing machine (MTS Systems Corporation, USA). Shear mechanical properties between implant and newly generated bone were...

  20. Isotopes in biological dinitrogen fixation

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-01

    Nineteen papers were presented at the conference. Some topics discussed are as follows: biochemistry and genetics of dinitrogen fixation; genetics of the Rhizobium-legume symbiosis and of the nitrogen-fixing bacteria; studies on nonsymbiotic dinitrogen fixation in grass-bacteria associations and blue--green algae; use of /sup 15/N and /sup 13/N for the assay of dinitrogen fixation; effects of management practices on dinitrogen fixation; economy of C and N in nitrogen-fixing legumes; and survey of international and national programs on dinitrogen fixation. (HLW)

  1. Solid recovered fuel production through the mechanical-biological treatment of wastes

    OpenAIRE

    Velis, C. A.

    2010-01-01

    This thesis is concerned with the production of solid recovered fuel (SRF) from municipal solid waste using mechanical biological treatment (MBT) plants. It describes the first in-depth analysis of a UK MBT plant and addresses the fundamental research question: are MBT plants and their unit operations optimised to produce high quality SRF in the UK? A critical review of the process science and engineering of MBT provides timely insights into the quality management and standa...

  2. Compression and contact area of anterior strut grafts in spinal instrumentation: a biomechanical study.

    Science.gov (United States)

    Pizanis, Antonius; Holstein, Jörg H; Vossen, Felix; Burkhardt, Markus; Pohlemann, Tim

    2013-08-26

    Anterior bone grafts are used as struts to reconstruct the anterior column of the spine in kyphosis or following injury. An incomplete fusion can lead to later correction losses and compromise further healing. Despite the different stabilizing techniques that have evolved, from posterior or anterior fixating implants to combined anterior/posterior instrumentation, graft pseudarthrosis rates remain an important concern. Furthermore, the need for additional anterior implant fixation is still controversial. In this bench-top study, we focused on the graft-bone interface under various conditions, using two simulated spinal injury models and common surgical fixation techniques to investigate the effect of implant-mediated compression and contact on the anterior graft. Calf spines were stabilised with posterior internal fixators. The wooden blocks as substitutes for strut grafts were impacted using a "pressfit" technique and pressure-sensitive films placed at the interface between the vertebral bone and the graft to record the compression force and the contact area with various stabilization techniques. Compression was achieved either with posterior internal fixator alone or with an additional anterior implant. The importance of concomitant ligament damage was also considered using two simulated injury models: pure compression Magerl/AO fracture type A or rotation/translation fracture type C models. In type A injury models, 1 mm-oversized grafts for impaction grafting provided good compression and fair contact areas that were both markedly increased by the use of additional compressing anterior rods or by shortening the posterior fixator construct. Anterior instrumentation by itself had similar effects. For type C injuries, dramatic differences were observed between the techniques, as there was a net decrease in compression and an inadequate contact on the graft occurred in this model. Under these circumstances, both compression and the contact area on graft could only

  3. Radiographic analysis of pasteurized autologous bone graft

    International Nuclear Information System (INIS)

    Ahmed, Adel Refaat; Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi

    2003-01-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  4. Radiographic analysis of pasteurized autologous bone graft

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Adel Refaat [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan); Department of Orthopedic Surgery, Alexandria University, Alexandria (Egypt); Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan)

    2003-08-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  5. CARBON DIOXIDE FIXATION.

    Energy Technology Data Exchange (ETDEWEB)

    FUJITA,E.

    2000-01-12

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

  6. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  7. Rib Bone Graft Adjusted to Fit the Facial Asymmetry: A Frame Structure Graft.

    Science.gov (United States)

    Lee, Yoon Ho; Choi, Jong Hwan; Hwang, Kun; Choi, Jun Ho

    2015-10-01

    The authors introduce the concept of a "frame structure graft" in which a harvested rib bone was adjusted to fit facial asymmetry. On the costochondral junction of the sixth or seventh rib, a 5 cm incision was made. Through a subperiosteal dissection, the rib bone was harvested. Using a reciprocating saw, the harvested rib was scored on its anterior surface as well as its posterior surface with a partial depth at different intervals. The harvested rib bone was placed on the skin surface of the unaffected side of the face and a curvature was created exactly matching that of the unaffected side by bending the bone using a greenstick fracture. Thereafter, the graft was adjusted to conceal the asymmetry of the deficient side. The adjusted "frame structure" was transferred to the defect through the incisions on the affected side, and the "frame structure" graft was placed on the mandible or zygoma. The graft fixation was done externally with at least 2 Kirschner wires (K-wires). From January 2005 to August 2013, a total of 30 patients (13 men, 17 women, mean age 25.6 years) received a frame structure graft. All 30 patients achieved good healing at the operation site without complications. Donor-site morbidity as pneumothorax from the rib bone harvest was not found. Merits of this frame structure graft, the authors think, are that this method could allow a similar curvature to the normal side. In addition, the procedure itself is easy.

  8. [Usefullness of intrasacral fixation in an extremely unstable lumbosacral spine].

    Science.gov (United States)

    Nishiura, Tsukasa; Nishiguchi, Mitsuhisa; Kusaka, Noboru; Takayama, Kazuhiro; Maeda, Yasuhiko; Ogihara, Kotaro; Nakagawa, Minoru

    2007-04-01

    Intrasacral fixation technique devised by Jackson is said to provide rigid lumbosacral fixation. We treated 3 cases of lumbosacral lesions using this technique in which lumbosacral segment had become extremely unstable during surgical intervention adding to the effect of original lesions. In all cases, surgeries were performed in 2 stages, intrasacral fixation and anterior stabilization. Case 1: A 52-year-old male was diagnosed fungal discitis and spondylitis at L4 and L5. X-ray showed destruction of the vertebral bodies. L2, L3 and sacrum were fixed posteriorly using the intrasacral fixation technique. One week after the first operation, L4 and L5 vertebral bodies were replaced by long fibula grafts through the extraperitoneal approach. Case 2: A 25-year-old female with cauda equina syndrome and abnormal body form diagnosed as having spondyloptosis in which the entire vertebral body of L5 had descended below the endplate of S1. MR imaging revealed marked canal stenosis at the S1 level. In the first surgery, L5 vertebral body was resected through the transperitoneal approach. After 1 week of bed rest, posterior segments of L5 were resected, L4 was affixed to the sacrum and anterior stabilization was achieved with 2 mesh cages and lumbosacral spine was fixed using the intrasacral fixation technique. Case 3: A 64-year-old female was diagnosed as having pyogenic discitis and osteomyelitis at the L5-S1 level. In spite of successful medical treatment for infection, low back pain continued. Radiologically, L5 vertebral body was shown to have collapsed and slipped anteriorly over the sacrum. L3, L4 and sacrum were fixed by intrasacral fixation. One week after the first operation, the L5/S1 disc and the suppurtive vertebral bodies were resected through the extraperitoneal approach and anterior stabilization was performed with iliac bone grafts. At follow-up for a minimum of 6 months, initial fixation was maintained in all 3 cases and bony fusion was obtained. The

  9. EXTERNAL FIXATION OF METACARPAL AND PHALANGAL FRACTURES

    Directory of Open Access Journals (Sweden)

    Krunoslav Margić

    2001-11-01

    Full Text Available Background. In past three years we have used smallexternal fixator in the treatment of: 18 closed fractures of metacarpalbones, 15 phalangeal fractures, four dislocated fracturesof MCP and five of PIP joint, ten arthrodesis, five replantations/revascularisations, two pathological fractures, and infew post-traumatic infection of bones and joints.Results. Results were graded as excellent (completely normalfunction, very good (15° deficit of total ROM, good (30° deficitof total ROM; can flex the fingers to the palm, and poor.Excellent result was obtained in the treatment of all 18 metacarpalfractures. The final results in the treatment of 12 closedfragmentated fractures of phalanges were as follows: excellent3, very good 2, good 2 and five poor results (three patientsin this group have fallen on their hands causing refractureand reoperation. Three of four fractures of MCP joint andfour of five fractures involving PIP joint have good mobility.In eight of ten patients arthrodeses are stable and withoutpain. In two cases pathological fractures were first stabilizedand than the tumor was evacuated and grafted with minimaldissection; booth have good results.Conclusion. Author suggests that, in selected cases, with applicationof small external fixator reasonable good results can beobtained.

  10. Collateral ligament reconstruction of the chronic thumb injury with bio-tenodesis screw fixation

    DEFF Research Database (Denmark)

    Gvozdenovic, Robert; Boeckstyns, Michel

    2014-01-01

    We describe a new technique for the reconstruction of chronic lesions of the collateral ligaments of the metacarpophalangeal ligaments of the thumb, using a Bio-Tenodesis screw for the fixation of a tendon graft in a triangular manner with proximal apex and allowing early mobilization, starting 2...

  11. Fixation distance and fixation duration to vertical road signs.

    Science.gov (United States)

    Costa, Marco; Simone, Andrea; Vignali, Valeria; Lantieri, Claudio; Palena, Nicola

    2018-05-01

    The distance of first-fixation to vertical road signs was assessed in 22 participants while driving a route of 8.34 km. Fixations to road signs were recorded by a mobile eye-movement-tracking device synchronized to GPS and kinematic data. The route included 75 road signs. First-fixation distance and fixation duration distributions were positively skewed. Median distance of first-fixation was 51 m. Median fixation duration was 137 ms with a modal value of 66 ms. First-fixation distance was linearly related to speed and fixation duration. Road signs were gazed at a much closer distance than their visibility distance. In a second study a staircase procedure was used to test the presentation-time threshold that lead to a 75% accuracy in road sign identification. The threshold was 35 ms, showing that short fixations to a road signs could lead to a correct identification. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. A case of monostotic fibrous dysplasia of proximal femur managed with curettage and cortical bone grafting

    Directory of Open Access Journals (Sweden)

    A D Sud

    2013-01-01

    Full Text Available We present a case report of a young military personnel with monostotic fibrous dysplasia of proximal femur with painful, dysplasticlesion of the femoral neck and fatigue fracture who underwent cortical bone grafting using autogenous fibular strut graft and iliac crest bone graft. The fibular cortical grafts was used to bridge the lesion in the femoral neck and were securely anchored to the normal bone of the lateral femoral cortex and a head of the femur. No supplemental internal fixation was required.

  13. Lateral column lengthening using allograft interposition and cervical plate fixation.

    Science.gov (United States)

    Philbin, Terrence M; Pokabla, Christopher; Berlet, Gregory C

    2008-10-01

    Lateral column lengthening has been used successfully in the treatment of stage II adult-acquired pes planovalgus deformity. The purpose of this study is to review the union rate when allograft material is used and the osteotomy stabilized with a cervical plate. A retrospective review was performed on 28 feet in 26 patients who underwent correction of stage II pes planovalgus deformity using a lateral column lengthening with allograft tricortical iliac crest stabilized with a cervical plate. Patients were evaluated preoperatively and postoperatively using a modified American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale and the Short Form-12 health survey, as well as radiographically by assessing the talonavicular coverage angle. At a mean follow-up of 9 months, the mean total modified AOFAS score and pain subscore were significantly higher (45.6 and 25.0, respectively) versus preoperatively (27.3 and 11.2, respectively). Graft incorporation occurred in all but one case, and the average length of time to union was 10.06 weeks. Complications included 4 hardware removals, 1 nonunion, 1 graft penetration of the calcaneocuboid joint, and 2 cases of calcaneocuboid joint arthritis. Lateral column lengthening using allograft tricortical iliac crest bone graft with cervical plate fixation is a viable option for the correction of acquired pes planovalgus deformity. Allograft bone avoids donor site morbidity of autogenous iliac crest grafts and was not shown to increase rates of nonunion. Cervical plate fixation avoids the necessity of penetrating the graft with a screw and is associated with high patient satisfaction and radiographic union.

  14. Mechanical-biological waste conditioning with controlled venting - the Meisenheim mechanical-biological waste conditioning plant; Mechanisch-biologische Restabfallbehandlung nach dem Kaminzugverfahren - MBRA Meisenheim

    Energy Technology Data Exchange (ETDEWEB)

    Hangen, H.O. [Abfallwirtschaftsbetrieb Landkreis Bad Kreuznach, Bad Kreuznach (Germany)

    1998-12-31

    The decision of the rural district of Bad Kreuznach to propose creating facilities for mechanical-biological waste conditioning at the new northern Meisenheim landfill was consistent and correct. It will ensure that the material deposited at this new, state-of-the-art landfill is organically `lean` and can be deposited with a high density. Preliminary sifting of the material prior to depositing safeguards that no improper components are inadvertently included. Three years of operation warrant the statement that waste components that cannot be appropriately biologically conditioned should be eliminated prior to rotting. (orig.) [Deutsch] Die Entscheidung des Landkreises Bad Kreuznach, der neu eingerichteten Norddeponie Meisenheim eine MBRA vorzuschlaten, war auf jeden Fall konsequent und richtig. Es ist damit sicher gestellt, dass in diesem neuen nach dem Stand der Technik eingerichteten Deponiebereich von Anfang an ein Material eingelagert wird, das `organisch abgemagert` ist und mit hoher Einbaudichte eingebaut werden kann. Die Sichtung des gesamten Deponie-Inputs in der Vorsortierhalle gibt ein Stueck Sicherheit, dass keine nicht zugelassenen Stoffe verdeckt dem Ablagerungsbereich der Deponie zugefuehrt werden. Nach mehr als 3 Jahren Betriebszeit kann festgestellt werden, dass biologisch nicht sinnvoll behandelbare Abfallbestandteile vor dem Rotteprozess abgetrennt werden sollten. (orig.)

  15. Grafting and curing

    International Nuclear Information System (INIS)

    Garnett, J.L.; Loo-Teck Ng; Visay Viengkhou

    1998-01-01

    Progress in radiation grafting and curing is briefly reviewed. The two processes are shown to be mechanistically related. The parameters influencing yields are examined particularly for grafting. For ionising radiation grafting systems (EB and gamma ray) these include solvents, substrate and monomer structure, dose and dose-rate, temperature and more recently role of additives. In addition, for UV grafting, the significance of photoinitiators is discussed. Current applications of radiation grafting and curing are outlined. The recent development of photoinitiator free grafting and curing is examined as well as the potential for the new excimer laser sources. The future application of both grafting and curing is considered, especially the significance of the occurrence of concurrent grafting during cure and its relevance in environmental considerations

  16. Skin graft - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100100.htm Skin graft - series—Normal anatomy To use the sharing features ... entire body, and acts as a protective barrier. Skin grafts may be recommended for: Extensive wounds Burns Specific ...

  17. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  18. Behavior of selected organic pollutants in municipal waste during the mechanical-biological progress of composting

    International Nuclear Information System (INIS)

    Drahosch, W.

    1998-06-01

    Municipal waste was investigated during the mechanical-biological process of composting. Waste from Burgenland is treated mechanically and biologically to reduce organic matter in the material and to keep gas building potential low before deposition. Samples were taken and analyzed during a period of 80 days. The parameters: temperature, dry-weight, glow loss, ammonium, nitrate and phenolic substances were measured to follow the composting process. It was found that the process was almost finished after a period of 40 days in which the material was breathed intensively. The content of polycyclic aromatic hydrocarbons and polychlorinated phenols decreased slightly. It was not clear whether this was due to microbiological activity or blowing-out effects. Polychlorinated biphenyls were found to be stable during composting. The concentrations were considered as high. Hepta- and octachlorinated dibenzodioxines were formed during the first 10 days. The increase of octachlorinated dibenzodioxin was threefold. Other dioxines and furanes remained unchanged. Finally it was found out that mechanical-biological waste treatment is insufficient in order to reduce organic pollutants effectively. (author)

  19. Mass balance to assess the efficiency of a mechanical-biological treatment

    International Nuclear Information System (INIS)

    Araujo Morais, J. de; Ducom, G.; Achour, F.; Rouez, M.; Bayard, R.

    2008-01-01

    Using mechanical-biological treatment of residual municipal solid waste, it is possible to significantly lower landfill volume and gas and leachate emissions. Moreover, the landfill characteristics are improved. The performance of the Mende (France) mechanical-biological treatment plant is assessed via mass balances coupled with manual sorting according to the MODECOM TM methodology and biochemical methane potential after 90 days of incubation. The site includes mechanical sorting operations, a rotary sequential bioreactor, controlled aerobic stabilisation corridors, maturation platforms, and a sanitary landfill site for waste disposal in separated cells. Results showed that several steps could be improved: after a first sieving step, about 12% of the potentially biodegradable matter is landfilled directly without any treatment; mechanical disintegration of papers and cardboards in the rotary sequential bioreactor is insufficient and leads to a high proportion of papers and cardboards being landfilled without further treatment. Two fine fractions go through stabilisation and maturation steps. At the end of the maturation step, about 54% of the potentially biodegradable matter is degraded. The biochemical methane potential after 90 days of incubation is reduced by 81% for one of the two fine fractions and reduced by 88% for the other one. Considering the whole plant, there is a reduction of nearly 20% DM of the entering residual municipal solid waste

  20. Biomechanical Strength of Retrograde Fixation in Proximal Third Scaphoid Fractures.

    Science.gov (United States)

    Daly, Charles A; Boden, Allison L; Hutton, William C; Gottschalk, Michael B

    2018-04-01

    Current techniques for fixation of proximal pole scaphoid fractures utilize antegrade fixation via a dorsal approach endangering the delicate vascular supply of the dorsal scaphoid. Volar and dorsal approaches demonstrate equivalent clinical outcomes in scaphoid wrist fractures, but no study has evaluated the biomechanical strength for fractures of the proximal pole. This study compares biomechanical strength of antegrade and retrograde fixation for fractures of the proximal pole of the scaphoid. A simulated proximal pole scaphoid fracture was produced in 22 matched cadaveric scaphoids, which were then assigned randomly to either antegrade or retrograde fixation with a cannulated headless compression screw. Cyclic loading and load to failure testing were performed and screw length, number of cycles, and maximum load sustained were recorded. There were no significant differences in average screw length (25.5 mm vs 25.6 mm, P = .934), average number of cyclic loading cycles (3738 vs 3847, P = .552), average load to failure (348 N vs 371 N, P = .357), and number of catastrophic failures observed between the antegrade and retrograde fixation groups (3 in each). Practical equivalence between the 2 groups was calculated and the 2 groups were demonstrated to be practically equivalent (upper threshold P = .010). For this model of proximal pole scaphoid wrist fractures, antegrade and retrograde screw configuration have been proven to be equivalent in terms of biomechanical strength. With further clinical study, we hope surgeons will be able to make their decision for fixation technique based on approaches to bone grafting, concern for tenuous blood supply, and surgeon preference without fear of poor biomechanical properties.

  1. 3D perfusion bioreactor-activated porous granules on implant fixation and early bone formation in sheep.

    Science.gov (United States)

    Ding, Ming; Henriksen, Susan S; Martinetti, Roberta; Overgaard, Søren

    2017-11-01

    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 to induce early implant fixation were tested in a bilateral implant defect model in sheep, with allograft as the control group. Defects were bilaterally created in the distal femurs of the animals, and titanium implants were inserted. The concentric gaps around the implants were randomly filled with either 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 no significant differences between groups were found regarding early implant fixation. The microarchitecture of the bone formed by the synthetic graft materials resembled that of allograft. Histomorphometry revealed that allograft induced significantly more bone and less fibrous tissue (p formation was observed in all groups, while the bioreactor-activated graft material did not reveal additional effects on early implant fixation comparable to allograft in this model. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2465-2476, 2017. © 2016 Wiley Periodicals, Inc.

  2. 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.

  3. 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, ...

  4. 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

    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......, bone formation was observed in all groups, while the bioreactor-activated graft material did not reveal additional effects on early implant fixation comparable to allograft in this model. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016....

  5. 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.

  6. Enhancing biological nitrogen fixation

    Energy Technology Data Exchange (ETDEWEB)

    Danso, S.K.A.; Eskew, D.L. (Joint FAO/IAEA Div. of Isotope and Radiation Applications of Atomic Energy for Food and Agricultural Development, Vienna (Austria))

    1984-06-01

    Several co-ordinated research programmes (CRPs) conducted by the Soil Fertility, Irrigation and Crop Production Section of the Joint FAO/IAEA Division have concentrated on finding the most efficient way of applying nitrogen fertilizers to various crops, using nitrogen-15 (/sup 15/N) as a tracer. The findings of these studies have been adopted in many countries around the world, resulting in savings of nitrogen fertilizers worth many millions of dollars every year. More recently, the Section's CRPs have focused on enhancing the natural process of biological di-nitrogen fixation. The /sup 15/N isotope technique has proven to be very valuable in studies of the legume-Rhizobium symbiosis, allowing many more experiments than before to be done and yielding much new practical information. The Soils Section is now working to extend the use of the technique to other nitrogen-fixing symbioses.

  7. Computed tomography evaluation of autogenous graft in sinus lift surgery

    International Nuclear Information System (INIS)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro; Alves, Maria Teresa de Seixas

    2001-01-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  8. Intended process water management concept for the mechanical biological treatment of municipal solid waste

    Institute of Scientific and Technical Information of China (English)

    D. Weichgrebe; S. Maerker; T. Boning; H. Stegemann

    2008-01-01

    Accumulating operational experience in both aerobic and anaerobic mechanical biological waste treatment (MBT) makes it increasingly obvious that controlled water management would substantially reduce the cost of MBT and also enhance resource recovery of the organic and inorganic fraction. The MBT plant at Gescher, Germany, is used as an example in order to determine the quantity and composition of process water and leachates from intensive and subsequent rotting, pressing water from anaerobic digestion and scrubber water from acid exhaust air treatment, and hence prepare an MBT water balance. The potential of, requirements for and limits to internal process water reuse as well as the possibilities of resource recovery from scrubber water are also examined. Finally, an assimilated process water management concept with the purpose of an extensive reduction of wastewater quantity and freshwater demand is presented.

  9. Shear strength characteristics of mechanically biologically treated municipal solid waste (MBT-MSW) from Bangalore

    International Nuclear Information System (INIS)

    Sivakumar Babu, G.L.; Lakshmikanthan, P.; Santhosh, L.G.

    2015-01-01

    Highlights: • Shear strength properties of mechanically biologically treated municipal solid waste. • Effect of unit weight and particle size on the shear strength of waste. • Effect of particle size on the strength properties. • Stiffness ratio and the strength ratio of MSW. - Abstract: Strength and stiffness properties of municipal solid waste (MSW) are important in landfill design. This paper presents the results of comprehensive testing of shear strength properties of mechanically biologically treated municipal solid waste (MBT-MSW) in laboratory. Changes in shear strength of MSW as a function of unit weight and particle size were investigated by performing laboratory studies on the MSW collected from Mavallipura landfill site in Bangalore. Direct shear tests, small scale and large scale consolidated undrained and drained triaxial tests were conducted on reconstituted compost reject MSW samples. The triaxial test results showed that the MSW samples exhibited a strain-hardening behaviour and the strength of MSW increased with increase in unit weight. Consolidated drained tests showed that the mobilized shear strength of the MSW increased by 40% for a unit weight increase from 7.3 kN/m 3 to 10.3 kN/m 3 at 20% strain levels. The mobilized cohesion and friction angle ranged from 5 to 9 kPa and 8° to 33° corresponding to a strain level of 20%. The consolidated undrained tests exhibited reduced friction angle values compared to the consolidated drained tests. The friction angle increased with increase in the unit weight from 8° to 55° in the consolidated undrained tests. Minor variations were found in the cohesion values. Relationships for strength and stiffness of MSW in terms of strength and stiffness ratios are developed and discussed. The stiffness ratio and the strength ratio of MSW were found to be 10 and 0.43

  10. Shear strength characteristics of mechanically biologically treated municipal solid waste (MBT-MSW) from Bangalore

    Energy Technology Data Exchange (ETDEWEB)

    Sivakumar Babu, G.L., E-mail: gls@civil.iisc.ernet.in [Department of Civil Engineering, Indian Institute of Science, Bangalore 560012 (India); Lakshmikanthan, P., E-mail: lakshmikanthancp@gmail.com [Centre for Sustainable Technologies (CST), Indian Institute of Science, Bangalore 560012 (India); Santhosh, L.G., E-mail: lgsanthu2006@gmail.com [Centre for Sustainable Technologies (CST), Indian Institute of Science, Bangalore 560012 (India)

    2015-05-15

    Highlights: • Shear strength properties of mechanically biologically treated municipal solid waste. • Effect of unit weight and particle size on the shear strength of waste. • Effect of particle size on the strength properties. • Stiffness ratio and the strength ratio of MSW. - Abstract: Strength and stiffness properties of municipal solid waste (MSW) are important in landfill design. This paper presents the results of comprehensive testing of shear strength properties of mechanically biologically treated municipal solid waste (MBT-MSW) in laboratory. Changes in shear strength of MSW as a function of unit weight and particle size were investigated by performing laboratory studies on the MSW collected from Mavallipura landfill site in Bangalore. Direct shear tests, small scale and large scale consolidated undrained and drained triaxial tests were conducted on reconstituted compost reject MSW samples. The triaxial test results showed that the MSW samples exhibited a strain-hardening behaviour and the strength of MSW increased with increase in unit weight. Consolidated drained tests showed that the mobilized shear strength of the MSW increased by 40% for a unit weight increase from 7.3 kN/m{sup 3} to 10.3 kN/m{sup 3} at 20% strain levels. The mobilized cohesion and friction angle ranged from 5 to 9 kPa and 8° to 33° corresponding to a strain level of 20%. The consolidated undrained tests exhibited reduced friction angle values compared to the consolidated drained tests. The friction angle increased with increase in the unit weight from 8° to 55° in the consolidated undrained tests. Minor variations were found in the cohesion values. Relationships for strength and stiffness of MSW in terms of strength and stiffness ratios are developed and discussed. The stiffness ratio and the strength ratio of MSW were found to be 10 and 0.43.

  11. Is Bone Grafting Necessary in the Treatment of Malunited Distal Radius Fractures?

    Science.gov (United States)

    Disseldorp, Dominique J. G.; Poeze, Martijn; Hannemann, Pascal F. W.; Brink, Peter R. G.

    2015-01-01

    Background Open wedge osteotomy with bone grafting and plate fixation is the standard procedure for the correction of malunited distal radius fractures. Bone grafts are used to increase structural stability and to enhance new bone formation. However, bone grafts are also associated with donor site morbidity, delayed union at bone–graft interfaces, size mismatch between graft and osteotomy defect, and additional operation time. Purpose The goal of this study was to assess bone healing and secondary fracture displacement in the treatment of malunited distal radius fractures without the use of bone grafting. Methods Between January 1993 and December 2013, 132 corrective osteotomies and plate fixations without bone grafting were performed for malunited distal radius fractures. The minimum follow-up time was 12 months. Primary study outcomes were time to complete bone healing and secondary fracture displacement. Preoperative and postoperative radiographs during follow-up were compared with each other, as well as with radiographs of the uninjured side. Results All 132 osteotomies healed. In two cases (1.5%), healing took more than 4 months, but reinterventions were not necessary. No cases of secondary fracture displacement or hardware failure were observed. Significant improvements in all radiographic parameters were shown after corrective osteotomy and plate fixation. Conclusion This study shows that bone grafts are not required for bone healing and prevention of secondary fracture displacement after corrective osteotomy and plate fixation of malunited distal radius fractures. Level of evidence Therapeutic, level IV, case series with no comparison group PMID:26261748

  12. Improved Bone Graft Method for Upper Cervical Surgery with Posterior Approach: Technical Description and Report of 52 Cases.

    Science.gov (United States)

    Wang, Yong-Li; Wang, Xiang-Yang

    2018-02-21

    We sought to report a minimum 12 months' follow-up results of our improved bone graft method for upper cervical surgery with the posterior approach. Among 52 consecutive cases, odontoid nonunion occurred in 33 patients, atlantoaxial instability in 11 patients, and occipitocervical deformity in 8 patients who underwent posterior C1-C2 transarticular screw/screw-rod internal fixation (41 cases) and occipitocervical fusion (11 cases) with the improved bone graft technique. Each surgical procedure was performed by the same senior spine surgeon. We took lateral cervical standing roentgenograms before surgery and immediately after surgery. Then we conducted craniocerebral computed tomography examination with reconstruction at 3, 6, 12, and 24 months and annually thereafter. The postoperative follow-up times are about 12-38 months. All cases showed satisfactory screw fixation by radiographic examination, and there were no postoperative neurologic complications. One case had postoperative retropharyngeal infection after the transoral release and posterior reduction by pedicle screw instrumentation. All patients got solid fusions, and no pseudarthrosis occurred. All cases had solid fusions at the 3-month follow-up. Good bone graft bed, enough bone graft material, solid local fixation, and effective bone graft method are prerequisites for a successful bone graft. By analyzing postoperative follow-up in the consecutive cases in this study, our bone graft method describing a new bone graft structure is a reliable posterior fusion technique. It is worth considering, and further research is needed. Copyright © 2018. Published by Elsevier Inc.

  13. REVISION ANKLE SYNDESMOSIS FIXATION - FUNCTIONAL OUTCOME AFTER TIGHTROPE ® FIXATION

    Directory of Open Access Journals (Sweden)

    Sendhilvelan Rajagopalan

    2016-07-01

    Full Text Available BACKGROUND Syndesmotic disruptions are often seen in ankle fractures. Malreduction of these fractures can result in arthritis and instability. A proportion of these patients with malreduction require revision fixation. This study presents the results of revision fixation in such patients, using the Ankle TightRope ® (Arthrex system. METHODS Between January 2000 to December 2009, 124 patients who underwent ankle fracture fixations with syndesmotic stabilisation were analysed. Out of 124 patients, 8 patients were diagnosed with failure of primary stabilisation (based on radiological and clinical criteria and subjected to revision fixation using the Ankle TightRope ® (Arthrex system. Followup was done at periodic time intervals of 3, 6 and 12 months. Both clinical and radiological assessment was performed. Complications and duration of hospital stay was recorded. Functional evaluation was performed using the American Orthopaedic Foot and Ankle Society (AOFAS scoring system. RESULTS Five patients had good results, one satisfactory and two had poor outcomes. CONCLUSIONS Ankle TightRope ® fixation is an alternative method of stabilisation in patients who require revision syndesmosis fixation. Further studies are required to evaluate this method of revision stabilisation as compared to screws.

  14. Nonunion of the humerus following intramedullary nailing treated by Ilizarov hybrid fixation.

    Science.gov (United States)

    Raschke, M; Khodadadyan, C; Maitino, P D; Hoffmann, R; Südkamp, N P

    1998-02-01

    A case of a posttraumatic humeral shaft nonunion, after intramedullary stabilization with a Seidel nail, is presented. Severe osteoporosis, an oligotrophic nonunion, subclinical infection, and adhesive capsulitis of the glenohumeral joint were present. Due to the subclinical infection and severe osteoporosis, other major invasive therapeutic options such as intramedullary nailing or compression plating and bone grafting were not applicable. Nonoperative treatment was also not indicated secondary to the pain and disability present. External fixation with the Ilizarov hybrid fixator seemed to offer a minimally invasive treatment modality without the need of additional bone grafting. After fourteen weeks of "callus massage," consisting of closed alternating compression and distraction with an Ilizarov hybrid fixator, osseous consolidation was achieved. Eight months after Ilizarov treatment the patient had returned to work as a mechanic. At the one-year follow-up examination, the patient presented pain free and with near normal shoulder and elbow motion, with stable osseous consolidation of the humerus. In some cases of nonunion of the humerus shaft, when standard treatment options are not recommended, external fixation with an Ilizarov hybrid fixator may offer a salvage procedure with a successful clinical outcome.

  15. Vascularized fibular graft in infected tibial bone loss

    Directory of Open Access Journals (Sweden)

    C Cheriyan Kovoor

    2011-01-01

    Full Text Available Background : The treatment options of bone loss with infections include bone transport with external fixators, vascularized bone grafts, non-vascularized autogenous grafts and vascularized allografts. The research hypothesis was that the graft length and intact ipsilateral fibula influenced hypertrophy and stress fracture. We retrospectively studied the graft hypertrophy in 15 patients, in whom vascularized fibular graft was done for post-traumatic tibial defects with infection. Materials and Methods : 15 male patients with mean age 33.7 years (range 18 - 56 years of post traumatic tibial bone loss were analysed. The mean bony defect was 14.5 cm (range 6.5 - 20 cm. The mean length of the graft was 16.7 cm (range 11.5 - 21 cm. The osteoseptocutaneous flap (bone flap with attached overlying skin flap from the contralateral side was used in all patients except one. The graft was fixed to the recipient bone at both ends by one or two AO cortical screws, supplemented by a monolateral external fixator. A standard postoperative protocol was followed in all patients. The hypertrophy percentage of the vascularized fibular graft was calculated by a modification of the formula described by El-Gammal. The followup period averaged 46.5 months (range 24 - 164 months. The Pearson correlation coefficient (r was worked out, to find the relationship between graft length and hypertrophy. The t-test was performed to find out if there was any significant difference in the graft length of those who had a stress fracture and those who did not and to find out whether there was any significant difference in hypertrophy with and without ipsilateral fibula union. The Chi square test was performed to identify whether there was any association between the stress fracture and the fibula union. Given the small sample size we have not used any statistical analysis to determine the relation between the percentage of the graft hypertrophy and stress fracture. Results : Graft

  16. Osseous scintigraphy and auxiliary graft

    International Nuclear Information System (INIS)

    Khelifa, F.; Siles, S.; Puech, B.

    1992-01-01

    The scintigraphy could be a good way to survey the osseous graft: three cases are studied in which were recognized the presence of a graft, surinfection, graft lysis, pseudo-arthrosis, algodystrophy. 8 refs., 5 figs

  17. Treatment of Unicameral Bone Cysts of the Proximal Femur With Internal Fixation Lessens the Risk of Additional Surgery.

    Science.gov (United States)

    Wilke, Benjamin; Houdek, Matthew; Rao, Rameshwar R; Caird, Michelle S; Larson, A Noelle; Milbrandt, Todd

    2017-09-01

    Little data exist to guide the treatment of unicameral bone cysts in the proximal femur. Methods of treatment include corticosteroid injections, curettage and bone grafting, and internal fixation. The authors completed a multi-institutional, retrospective review to evaluate their experience with proximal femoral unicameral bone cysts. They posed the following questions: (1) Does internal fixation reduce the risk of further procedures for the treatment of a unicameral bone cyst? (2) Is radiographic healing faster with internal fixation? Following institutional review board approval, the authors conducted a retrospective review of 36 patients treated for a unicameral bone cyst of the proximal femur at their institutions between 1974 and 2014. Medical records and radiographs were reviewed to identify patient demographics and treatment outcomes. Tumor locations included femoral neck (n=13), intertrochanteric (n=16), and subtrochanteric (n=7). Initial treatment included steroid injection (n=2), curettage and bone grafting (n=9), and internal fixation with curettage and bone grafting (n=25). Mean time was 9 months to radiographic healing and 15 months to return to full activity. The number of patients requiring additional surgeries was increased among those who did not undergo internal fixation. There was no difference in time to radiographic healing. However, time to return to normal activities was reduced if patients had received internal fixation. A significant reduction in additional procedures was observed when patients had been treated with internal fixation. Although this did not influence time to radiographic healing, patients did return to normal activities sooner. Internal fixation should be considered in the treatment of proximal femoral unicameral bone cysts. [Orthopedics. 2017; 40(5):e862-e867.]. Copyright 2017, SLACK Incorporated.

  18. Endovascular AAA exclusion: will stents with hooks and barbs prevent stent-graft migration?

    Science.gov (United States)

    Malina, M; Lindblad, B; Ivancev, K; Lindh, M; Malina, J; Brunkwall, J

    1998-11-01

    To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta. Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force. The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects. Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.

  19. Advances in radiation grafting

    International Nuclear Information System (INIS)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H.A.; Kamal, H.; Kandeel, K.A.

    2001-01-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed

  20. Bone graft revascularization strategies

    NARCIS (Netherlands)

    Willems, W.F.

    2014-01-01

    Reconstruction of avascular necrotic bone by pedicled bone grafting is a well-known treatment with little basic research supporting its application. A new canine model was used to simulate carpal bone avascular necrosis. Pedicled bone grafting proved to increase bone remodeling and bone blood flow,

  1. Permanganate Fixation of Plant Cells

    Science.gov (United States)

    Mollenhauer, Hilton H.

    1959-01-01

    In an evaluation of procedures explored to circumvent some of the problems of osmium tetroxide-fixation and methacrylate embedding of plant materials, excised segments of root tips of Zea mays were fixed for electron microscopy in potassium permanganate in the following treatment variations: unbuffered and veronal-acetate buffered solutions of 0.6, 2.0, and 5.0 per cent KMnO4 at pH 5.0, 6.0, 6.7, and 7.5, and temperatures of 2–4°C. and 22°C. After fixation the segments were dehydrated, embedded in epoxy resin, sectioned, and observed or photographed. The cells of the central region of the rootcap are described. The fixation procedures employing unbuffered solutions containing 2.0 to 5.0 per cent KMnO4 at a temperature of 22°C. gave particularly good preservation of cell structure and all membrane systems. Similar results were obtained using a solution containing 2.0 per cent KMnO4, buffered with veronal-acetate to pH 6.0, and a fixation time of 2 hours at 22°C. The fixation procedure utilizing veronal-acetate buffered, 0.6 per cent KMnO4 at 2–4°C. and pH 6.7 also gave relatively good preservation of most cellular constituents. However, preservation of the plasma membrane was not so good, nor was the intensity of staining so great, as that with the group of fixatives containing greater concentrations of KMnO4. The other fixation procedures did not give satisfactory preservation of fine structure. A comparison is made of cell structures as fixed in KMnO4 or OsO4. PMID:14423414

  2. Water regime of mechanical-biological pretreated waste materials under fast-growing trees.

    Science.gov (United States)

    Rüth, Björn; Lennartz, Bernd; Kahle, Petra

    2007-10-01

    In this study mechanical-biological pre-treated waste material (MBP) was tested for suitability to serve as an alternative surface layer in combination with fast-growing and water-consumptive trees for final covers at landfill sites. The aim was to quantify evapotranspiration and seepage losses by numerical model simulations for two sites in Germany. In addition, the leaf area index (LAI) of six tree species over the growing season as the driving parameter for transpiration calculations was determined experimentally. The maximum LAI varied between 3.8 and 6.1 m2 m(-2) for poplar and willow clones, respectively. The evapotranspiration calculations revealed that the use of MBP waste material for re-cultivation enhanced evapotranspiration by 40 mm year(-1) (10%) over an 11 year calculation period compared to a standard mineral soil. Between 82% (for LAI(max) = 3.8) and 87% (for LAI(max) = 6.1) of the average annual precipitation (506 mm) could be retained from the surface layer assuming eastern German climate conditions, compared with a retention efficiency between 79 and 82% for a mineral soil. Although a MBP layer in conjunction with water-consumptive trees can reduce vertical water losses as compared to mineral substrates, the effect is not sufficient to meet legal regulations.

  3. Investigations on mechanical biological treatment of waste in South America: Towards more sustainable MSW management strategies

    International Nuclear Information System (INIS)

    Bezama, Alberto; Aguayo, Pablo; Konrad, Odorico; Navia, Rodrigo; Lorber, Karl E.

    2007-01-01

    This work presents an analysis on the suitability of mechanical biological treatment of municipal solid waste in South America, based on two previous experimental investigations carried out in two different countries. The first experiment was performed for determining the mass and volume reduction of MSW in the province of Concepcion (Chile). The implemented bench-scale process consisted of a manual classification and separation stage, followed by an in-vessel biological degradation process. The second experiment consisted of a full-scale experiment performed in the city of Estrela (Brazil), where the existing municipal waste management facility was adapted to enhance the materials sorting and separation. Expressed in wet weight composition, 85.5% of the material input in the first experiment was separated for biological degradation. After 27 days of processing, 60% of the initial mass was reduced through degradation and water evaporation. The final fraction destined for landfilling equals 59% of the total input mass, corresponding to about 50% of the initial volume. In the second experiment, the fraction destined to landfill reaches 46.6% of the total input waste mass, whilst also significantly reducing the total volume to be disposed. These results, and the possible recovery of material streams suitable for recycling or for preparing solid recovered fuels, are the main advantages of the studied process

  4. Performance of mechanical biological treatment of residual municipal waste in Poland

    Science.gov (United States)

    den Boer, Emilia; Jędrczak, Andrzej

    2017-11-01

    The number and capacity of mechanical-biological treatment (MBT) plants in Europe increased significantly in the past two decades as a response to the legal obligation to limit the landfilling of biodegradable waste in landfills and to increase recycling and energy recovery from waste. The aim of these plants is to prepare residual municipal waste for recovery and disposal operations, including especially separation and stabilization of the easily biodegradable fraction (the biofraction). The final products of MBP technology are recyclables, stabilate, high calorific fraction which is used for the production of refuse derived fuel (RDF) and the remaining residual fraction. The shares of the output fractions, especially of the recyclables and RDF determine the overall efficiency of MBT technology in diverting waste from landfills. In this paper results of an assessment of one exemplary MBT plant are provided. The analysis was performed within a comparative study in which 20 selected MBT plants in Poland were subject to a detailed analysis, focusing, both at the design parameters as well as operational ones. The selected plant showed relatively higher overall materials recovery efficiency. With the view to circular economy targets, increased automation of the mechanical waste treatment will be required to support achieving high level diversion from landfills. The study reviled that stabilisation of biofraction should be improved by a better control of process conditions, especially moisture content.

  5. External fixation of "intertrochanteric" fractures.

    Science.gov (United States)

    Gani, Naseem Ul; Kangoo, Khursheed Ahmed; Bashir, Arshad; Muzaffer, Rahil; Bhat, Mohammad Farooq; Farooq, Munir; Badoo, Abdul Rashid; Dar, Imtiyaz Hussian; Wani, Mudassir Maqbool

    2009-10-10

    In developing countries, due to limited availability of modern anesthesia and overcrowding of the hospitals with patients who need surgery, high-risk patients with "intertrochanteric" fractures remain unsuita ble for open reduction and internal fixation.The aim of this study was to analyze the results of external fixation of "intertrochanteric" fractures in high-risk geriatric patients in a developing country.The results of 62 ambulatory high-risk geriatric patients with a mean age of 70 years (range 58-90 years) with "intertrochanteric" fractures, in whom external fixation was performed, are reported.Eight patients died during follow-up due to medical causes unrelated to the surgical procedure. So only 54 patients were available for final assessment. Procedure is simple, performed under local anesthesia, requires less time for surgery and is associated with less blood loss. Good fixation and early ambulation was achieved in most of the patients. Average time to union was 14 weeks. Thirty-one patients developed superficial pin tract infection and 28 patients had average shortening of 15 mm due to impaction and varus angulation. Functional outcome was assessed using Judet's point system. Good to excellent results were achieved in 44 patients.This study demonstrated that external fixation of "intertrochantric" fractures performed under local anesthesia offers significant advantage in ambulatory high-risk geriatric patients especially in a developing country.

  6. Mechanical-biological waste treatment and the associated occupational hygiene in Finland

    International Nuclear Information System (INIS)

    Tolvanen, Outi K.; Haenninen, Kari I.

    2006-01-01

    A special feature of waste management in Finland has been the emphasis on the source separation of kitchen biowaste (catering waste); more than two-thirds of the Finnish population participates in this separation. Source-separated biowaste is usually treated by composting. The biowaste of about 5% of the population is handled by mechanical-biological treatment. A waste treatment plant at Mustasaari is the only plant in Finland using digestion for kitchen biowaste. For the protection of their employees, the plant owners commissioned a study on environmental factors and occupational hygiene in the plant area. During 1998-2000 the concentrations of dust, microbes and endotoxins and noise levels were investigated to identify possible problems at the plant. Three different work areas were investigated: the pre-processing and crushing hall, the bioreactor hall and the drying hall. Employees were asked about work-related health problems. Some problems with occupational hygiene were identified: concentrations of microbes and endotoxins may increase to levels harmful to health during waste crushing and in the bioreactor hall. Because employees complained of symptoms such as dry cough and rash or itching appearing once or twice a month, it is advisable to use respirator masks (class P3) during dusty working phases. The noise level in the drying hall exceeded the Finnish threshold value of 85 dBA. Qualitatively harmful factors for the health of employees are similar in all closed waste treatment plants in Finland. Quantitatively, however, the situation at the Mustasaari treatment plant is better than at some Finnish dry waste treatment plants. Therefore is reasonable to conclude that mechanical sorting, which produces a dry waste fraction for combustion and a biowaste fraction for anaerobic treatment, is in terms of occupational hygiene better for employees than combined aerobic treatment and dry waste treatment

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

    Science.gov (United States)

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

    2003-06-01

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

  8. 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.

  9. New organophilic kaolin clays based on single-point grafted 3-aminopropyl dimethylethoxysilane.

    Science.gov (United States)

    Zaharia, A; Perrin, F-X; Teodorescu, M; Radu, A-L; Iordache, T-V; Florea, A-M; Donescu, D; Sarbu, A

    2015-10-14

    In this study, the organophilization procedure of kaolin rocks with a monofunctional ethoxysilane- 3 aminopropyl dimethyl ethoxysilane (APMS) is depicted for the first time. The two-step organophilization procedure, including dimethyl sulfoxide intercalation and APMS grafting onto the inner hydroxyl surface of kaolinite (the mineral) layers was tested for three sources of kaolin rocks (KR, KC and KD) with various morphologies and kaolinite compositions. The load of APMS in the kaolinite interlayer space was higher than that of 3-aminopropyl triethoxysilane (APTS) due to the single-point grafting nature of the organophilization reaction. A higher long-distance order of kaolinite layers with low staking was obtained for the APMS, due to a more controllable organiphilization reaction. Last but not least, the solid state (29)Si-NMR tests confirmed the single-point grafting mechanism of APMS, corroborating monodentate fixation on the kaolinite hydroxyl facets, with no contribution to the bidentate or tridentate fixation as observed for APTS.

  10. Sacral Fracture Nonunion Treated by Bone Grafting through a Posterior Approach

    Directory of Open Access Journals (Sweden)

    Sang Yang Lee

    2013-01-01

    Full Text Available Nonunion of a sacral fracture is a rare but serious clinical condition which can cause severe chronic pain, discomfort while sitting, and significant restriction of the level of activities. Fracture nonunions reportedly occur most often after nonoperative initial treatment or inappropriate operative treatment. We report a case of fracture nonunion of the sacrum and pubic rami that resulted from non-operative initial treatment, which was treated successfully using bone grafting through a posterior approach and CT-guided percutaneous iliosacral screw fixation combined with anterior external fixation. Although autologous bone grafting has been the gold standard for the treatment of pelvic fracture nonunions, little has been written describing the approach. We utilized a posterior approach for bone grafting, which could allow direct visualization of the nonunion site and preclude nerve root injury. By this procedure, we were able to obtain the healing of fracture nonunion, leading to pain relief and functional recovery.

  11. Accidental perforation of the lateral femoral cortex in ACL reconstruction: an investigation of mechanical properties of different fixation techniques.

    Science.gov (United States)

    Herbort, Mirco; Heletta, Sebastian; Raschke, Michael J; Schliemann, Benedikt; Osada, Nani; Petersen, Wolf; Zantop, Thore

    2012-03-01

    The aim of this study was to evaluate the mechanical properties of anterior cruciate ligament (ACL) reconstruction using the medial portal technique with cortical fixation and hybrid fixation after penetration of the lateral cortex by use of different drill sizes. In this biomechanical study a porcine in vitro model was used. The testing protocol consisted of a cyclic loading protocol (1,000 cycles, 50 and 250 N) and subsequent ultimate failure testing. Number of cyclic loadings survived, stiffness, yield load, maximum load, and graft elongation, as well as failure mode, were analyzed after ACL reconstruction with 5- to 9-mm soft-tissue grafts. In the control group, conventional penetration of the lateral cortex with a 4.5-mm drill and cortical fixation were performed. In the tested groups, the lateral cortex was penetrated with a drill matching the graft size. In the first part of the study, we used cortical fixation. In the second part, we used hybrid fixation with an interference screw. In the first part of the study, ACL reconstruction with 5- to 6-mm perforation of the lateral cortex showed no significant differences in ultimate failure load after cyclic loading compared with the control group (P > .05). Specimens with reconstruction with 7- to 9-mm perforation of the lateral cortex and cortical fixation did not survive the cyclic loading protocol. In the second part of the study, with a hybrid fixation technique, ultimate failure testing after cyclic loading of specimens with 7- to 9-mm penetration showed no significant differences in tested parameters compared with the control group (P > .05). After penetration of the lateral cortex with a drill size of more than 6 mm, cortical ACL fixation results in poor mechanical properties. Hybrid fixation increases the mechanical properties significantly after penetration with a 7- to 9-mm drill. We advise caution to avoid penetration of the lateral femoral cortex when using cortical flip-button fixation. In case of

  12. 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

  13. Management of paediatric tibial fractures using two types of circular external fixator: Taylor spatial frame and Ilizarov circular fixator.

    Science.gov (United States)

    Tafazal, Suhayl; Madan, Sanjeev S; Ali, Farhan; Padman, Manoj; Swift, Simone; Jones, Stanley; Fernandes, James A

    2014-05-01

    The use of circular fixators for the treatment of tibial fractures is well established in the literature. The aim of this study was to compare the Ilizarov circular fixator (ICF) with the Taylor spatial frame (TSF) in terms of treatment results in consecutive patients with tibial fractures that required operative management. A retrospective analysis of patient records and radiographs was performed to obtain patient data, information on injury sustained, the operative technique used, time duration in frame, healing time and complications of treatment. The minimum follow-up was 24 months. Ten patients were treated with ICF between 2000 and 2005, while 15 patients have been treated with TSF since 2005. Two of the 10 treated with ICF and 5 of the 15 treated with TSF were open fractures. All patients went on to achieve complete union. Mean duration in the frame was 12.7 weeks for ICF and 14.8 weeks for the TSF group. Two patients in the TSF group had delayed union and required additional procedures including adjustment of fixator and bone grafting. There was one malunion in the TSF group that required osteotomy and reapplication of frame. There were seven and nine pin-site infections in the ICF and TSF groups, respectively, all of which responded to antibiotics. There were no refractures in either group. In an appropriate patient, both types of circular fixator are equally effective but have different characteristics, with TSF allowing for postoperative deformity correction. Of concern are the two cases of delayed union in the TSF group, all in patients with high-energy injuries. We feel another larger study is required to provide further clarity in this matter. Level II-comparative study.

  14. Energy implications of mechanical and mechanical-biological treatment compared to direct waste-to-energy.

    Science.gov (United States)

    Cimpan, Ciprian; Wenzel, Henrik

    2013-07-01

    Primary energy savings potential is used to compare five residual municipal solid waste treatment systems, including configurations with mechanical (MT) and mechanical-biological (MBT) pre-treatment, which produce waste-derived fuels (RDF and SRF), biogas and/or recover additional materials for recycling, alongside a system based on conventional mass burn waste-to-energy and ash treatment. To examine the magnitude of potential savings we consider two energy efficiency levels (state-of-the-art and best available technology), the inclusion/exclusion of heat recovery (CHP vs. PP) and three different background end-use energy production systems (coal condensing electricity and natural gas heat, Nordic electricity mix and natural gas heat, and coal CHP energy quality allocation). The systems achieved net primary energy savings in a range between 34 and 140 MJprimary/100 MJinput waste, in the different scenario settings. The energy footprint of transportation needs, pre-treatment and reprocessing of recyclable materials was 3-9.5%, 1-18% and 1-8% respectively, relative to total energy savings. Mass combustion WtE achieved the highest savings in scenarios with CHP production, nonetheless, MBT-based systems had similarly high performance if SRF streams were co-combusted with coal. When RDF and SRF was only used in dedicated WtE plants, MBT-based systems totalled lower savings due to inherent system losses and additional energy costs. In scenarios without heat recovery, the biodrying MBS-based system achieved the highest savings, on the condition of SRF co-combustion. As a sensitivity scenario, alternative utilisation of SRF in cement kilns was modelled. It supported similar or higher net savings for all pre-treatment systems compared to mass combustion WtE, except when WtE CHP was possible in the first two background energy scenarios. Recovery of plastics for recycling before energy recovery increased net energy savings in most scenario variations, over those of full

  15. Histologic Evaluation of Critical Size Defect Healing With Natural and Synthetic Bone Grafts in the Pigeon ( Columba livia ) Ulna.

    Science.gov (United States)

    Tunio, Ahmed; Jalila, Abu; Goh, Yong Meng; Shameha-Intan; Shanthi, Ganabadi

    2015-06-01

    Fracture and bone segment loss are major clinical problems in birds. Achieving bone formation and clinical union in a fracture case is important for the survival of the bird. To evaluate the efficacy of bone grafts for defect healing in birds, 2 different bone grafts were investigated in the healing of a bone defect in 24 healthy pigeons ( Columba livia ). In each bird, a 1-cm critical size defect (CSD) was created in the left ulna, and the fracture was stabilized with external skeletal fixation (ESF). A graft of hydroxyapatite (HA) alone (n = 12 birds) or demineralized bone matrix (DBM) combined with HA (n = 12 birds) was implanted in the CSD. The CSD healing was evaluated at 3 endpoints: 3, 6, and 12 weeks after surgery. Four birds were euthanatized at each endpoint from each treatment group, and bone graft healing in the ulna CSD was evaluated by histologic examination. The CSD and graft implants were evaluated for quality of union, cortex development, and bone graft incorporation. Results showed no graft rejection in any bird, and all birds had connective tissue formation in the defect because of the bone graft application. These results suggest that bone defect healing can be achieved by a combination of osteoinductive and osteoconductive bone graft materials for clinical union and new bone regeneration in birds. The combination of DBM and HA resulted in a better quality bone graft (P < .05) than did HA alone, but there was no significant differences in cortex development or bone graft incorporation at 3, 6, or 12 weeks. From the results of this study, we conclude that HA bone grafts, alone or in combination with DBM, with external skeletal fixation is suitable and safe for bone defect and fracture treatment in pigeons.

  16. Does a plant for mechanical-biological waste treatment require a sanitary landfill?; Braucht die MBA eine Deponie?

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, Burkart [GVoA mbH und Co. KG, Hille (Germany)

    2012-11-01

    In mechanical-biological waste treatment, an interesting recyclable fraction is dumped in landfill together with other treatment residues. This may be 10-20% depending on the energy content of the initial material. Some operators of mechanical-biological waste treatment plants are currently working on modifying their waste treatment processes. Results so far have shown that this may also reduce the cost. (orig.) [German] Bei der bisherigen Abfallentsorgung mittels einer MBA (mechanisch-biologische Abfallbehandlung) wird immer noch ein interessanter Wertstoffanteil mit dem Deponat auf der Deponie abgelagert. Je nach Qualitaet der Vorbehandlung sind dies alleine vom Energieinhalt des Eingangsmaterials ca. 10-20%. Um auch diesen Anteil zu verwerten, sind aktuell einige MBA-Betreiber dabei, ihre Verfahren entsprechend umzustellen. Erste Ergebnisse zeigen, dass dies auch noch zu Kosteneinsparungen fuehren kann. (orig.)

  17. Biomechanical Evaluation of Glenoid Reconstruction With an Implant-Free J-Bone Graft for Anterior Glenoid Bone Loss.

    Science.gov (United States)

    Pauzenberger, Leo; Dyrna, Felix; Obopilwe, Elifho; Heuberer, Philipp R; Arciero, Robert A; Anderl, Werner; Mazzocca, Augustus D

    2017-10-01

    The anatomic restoration of glenoid morphology with an implant-free J-shaped iliac crest bone graft offers an alternative to currently widely used glenoid reconstruction techniques. No biomechanical data on the J-bone grafting technique are currently available. To evaluate (1) glenohumeral contact patterns, (2) graft fixation under cyclic loading, and (3) the initial stabilizing effect of anatomic glenoid reconstruction with the implant-free J-bone grafting technique. Controlled laboratory study. Eight fresh-frozen cadaveric shoulders and J-shaped iliac crest bone grafts were used for this study. J-bone grafts were harvested, prepared, and implanted according to a previously described, clinically used technique. Glenohumeral contact patterns were measured using dynamic pressure-sensitive sensors under a compressive load of 440 N with the humerus in (a) 30° of abduction, (b) 30° of abduction and 60° of external rotation, (c) 60° of abduction, and (d) 60° of abduction and 60° of external rotation. Using a custom shoulder-testing system allowing positioning with 6 degrees of freedom, a compressive load of 50 N was applied, and the peak force needed to translate the humeral head 10 mm anteriorly at a rate of 2.0 mm/s was recorded. All tests were performed (1) for the intact glenoid, (2) after the creation of a 30% anterior osseous glenoid defect parallel to the longitudinal axis of the glenoid, and (3) after anatomic glenoid reconstruction with an implant-free J-bone graft. Furthermore, after glenoid reconstruction, each specimen was translated anteriorly for 5 mm at a rate of 4.0 mm/s for a total of 3000 cycles while logging graft protrusion and mediolateral bending motions. Graft micromovements were recorded using 2 high-resolution, linear differential variable reluctance transducer strain gauges placed in line with the long leg of the graft and the mediolateral direction, respectively. The creation of a 30% glenoid defect significantly decreased glenohumeral

  18. Nonunited humerus shaft fractures treated by external fixator augmented by intramedullary rod

    Directory of Open Access Journals (Sweden)

    Mahmoud A El-Rosasy

    2012-01-01

    Full Text Available Background: Nonunion of humeral shaft fractures after previously failed surgical treatment presents a challenging therapeutic problem especially in the presence of osteoporosis, bone defect, and joint stiffness. It would be beneficial to combine the use of external fixation technique and intramedullary rod in the treatment of such cases. The present study evaluates the results of using external fixator augmented by intramedullary rod and autogenous iliac crest bone grafting (ICBG for the treatment of humerus shaft nonunion following previously failed surgical treatment. Materials and Methods: Eighteen patients with atrophic nonunion of the humeral shaft following previous implant surgery with no active infection were included in the present study. The procedure included exploration of the nonunion, insertion of intramedullary rod (IM rod, autogenous ICBG and application of external fixator for compression. Ilizarov fixator was used in eight cases and monolateral fixator in ten cases. The monolateral fixator was preferred for females and obese patients to avoid abutment against the breast or chest wall following the use of Ilizarov fixator. The fixator was removed after clinical and radiological healing of the nonunion, but the IM rod was left indefinitely. The evaluation of results included both bone results (union rate, angular deformity and limb shortening and functional outcome using the University of California, Los Angeles (UCLA rating scale. Results: The mean follow-up was 35 months (range 24 to 52 months. Bone union was obtained in all cases. The functional outcome was satisfactory in 15 cases (83% and unsatisfactory in 3 cases (17% due to joint stiffness. The time to bone healing averaged 4.2 months (range 3 to 7 months. The external fixator time averaged 4.5 months (range 3.2 to 8 months. Superficial pin tract infection occurred in 39% (28/72 of the pins. No cases of nerve palsy, refracture, or deep infection were encountered

  19. Graft-Sparing Strategy for Thoracic Prosthetic Graft Infection.

    Science.gov (United States)

    Uchino, Gaku; Yoshida, Takeshi; Kakii, Bunpachi; Furui, Masato

    2018-04-01

     Thoracic prosthetic graft infection is a rare but serious complication with no standard management. We reported our surgical experience on graft-sparing strategy for thoracic prosthetic graft infection.  This study included patients who underwent graft-sparing surgery for thoracic prosthetic graft infection at Matsubara Tokushukai Hospital in Japan from January 2000 to October 2017.  There were 17 patients included in the analyses, with a mean age at surgery of 71.0 ± 10.5 years; 11 were men. In-hospital mortality was observed in five patients (29.4%).  Graft-sparing surgery for thoracic prosthetic graft infection is an alternative option particularly for early graft infection after hemiarch replacement. Georg Thieme Verlag KG Stuttgart · New York.

  20. Fixation strength of biocomposite wedge interference screw in ACL reconstruction: effect of screw length and tunnel/screw ratio. A controlled laboratory study

    Directory of Open Access Journals (Sweden)

    Herrera Antonio

    2010-06-01

    Full Text Available Abstract Background Primary stability of the graft is essential in anterior cruciate ligament surgery. An optimal method of fixation should be easy to insert and provide great resistance against pull-out forces. A controlled laboratory study was designed to test the primary stability of ACL tendinous grafts in the tibial tunnel. The correlation between resistance to traction forces and the cross-section and length of the screw was studied. Methods The tibial phase of ACL reconstruction was performed in forty porcine tibias using digital flexor tendons of the same animal. An 8 mm tunnel was drilled in each specimen and two looped tendons placed as graft. Specimens were divided in five groups according to the diameter and length of the screw used for fixation. Wedge interference screws were used. Longitudinal traction was applied to the graft with a Servohydraulic Fatigue System. Load and displacement were controlled and analyzed. Results The mean loads to failure for each group were 295,44 N (Group 1; 9 × 23 screw, 564,05 N (Group 2; 9 × 28, 614,95 N (Group 3; 9 × 35, 651,14 N (Group 4; 10 × 28 and 664,99 (Group 5; 10 × 35. No slippage of the graft was observed in groups 3, 4 and 5. There were significant differences in the load to failure among groups (ANOVA/P Conclusions Longer and wider interference screws provide better fixation in tibial ACL graft fixation. Short screws (23 mm do not achieve optimal fixation and should be implanted only with special requirements.

  1. Is staged external fixation a valuable strategy for war injuries to the limbs?

    Science.gov (United States)

    Lerner, Alexander; Fodor, Lucian; Soudry, Michael

    2006-07-01

    High-energy weapons or blast injuries usually result in substantial tissue damage and are serious medical and public health problems. We report our experience with staged external fixation for war injuries to the extremities. Forty-seven patients with 64 high-energy limb fractures caused by war weapons were retrospectively reviewed. The fractures were associated with severe soft tissue damage. There were 14 Gustilo-Anderson Type IIIA fractures, 40 Type IIIB fractures, and 10 Type IIIC fractures. Soft tissue débridement followed by axial realignment of the fractured bones with immediate skeletal stabilization using the AO/ASIF unilateral tubular external fixator was performed on the day of admission. The primary tubular fixators were exchanged 5 to 7 days later for Ilizarov frames. Delayed primary closure, skin grafts, or flaps were used for soft tissue coverage. The mean followup was 40 months, and the Ilizarov/hybrid external fixator was the definitive treatment in all patients. Bone union was achieved at an average of 8 months in 58 (90.6%) fractures. Three patients had nonunions and one patient required an amputation. Two patients were lost to followup. Staged external fixation is a valuable strategy for treatment of war injuries to the extremities. Therapeutic study, Level IV. See the Guidelines for Authors for a complete description of levels of evidence.

  2. Anterior fixation of the axis.

    Science.gov (United States)

    Traynelis, Vincent C; Fontes, Ricardo B V

    2010-09-01

    Although anterior fixation of the axis is not commonly performed, plate fixation of C2 is an important technique for treating select upper cervical traumatic injuries and is also useful in the surgical management of spondylosis. To report the technique and outcomes of C2 anterior plate fixation for a series of patients in which the majority presented with symptomatic degenerative spondylosis. Forty-six consecutive patients underwent single or multilevel fusions over a 7-year period; 30 of these had advanced degenerative disease manifested by myelopathy or deformity. Exposure was achieved with rostral extension of the standard anterior cervical exposure via careful soft tissue dissection, mobilization of the superior thyroid artery, and the use of a table-mounted retractor. It was not necessary to remove the submandibular gland, section the digastric muscle, or make additional skin incisions. Screws were placed an average of 4.6 mm (+/- 2.3 mm) from the inferior C2 endplate with a mean sagittal trajectory of 15.7 degrees (+/- 7.6 degrees). Short- and long-term procedure-related mortality was 4.4%, and perioperative morbidity was 8.9%. Patients remained intubated an average of 2.5 days following surgery. Dysphagia was initially reported by 15.2% of patients but resolved by the 8th postoperative week in all patients. Arthrodesis was achieved in all patients available for long-term follow-up. Multilevel fusions were not associated with longer hospitalization or morbidity. Anterior plate fixation of the axis for degenerative disease can be accomplished with acceptable morbidity employing an extension of the standard anterolateral route.

  3. Arteriovenous shunt graft ulceration with sinus and graft epithelialization

    Directory of Open Access Journals (Sweden)

    Pooja Singhal

    2015-03-01

    Full Text Available Arteriovenous fistula and grafts are used as access sites for patients with chronic kidney disease and are prone for complications. Stent grafts are used to treat access site complications. We report a rare and unusual finding of epithelialization of the sinus tract and the lumen of a polytetrafluoroethylene graft, following ulceration of the overlying skin.

  4. 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.

  5. An alternative method in mandibular fracture treatment: bone graft use instead of a plate.

    Science.gov (United States)

    Alagöz, Murat Sahin; Uysal, Ahmet Cagri; Sensoz, Omer

    2008-03-01

    In the treatment of the mandibular fractures, one of the main principles is to use the least amount of foreign material. We present an alternative technique that the bone grafts harvested from the fracture borders or from the iliac crest were used instead of plates and the fixation was done with screws. In the study including 24 mandible fractures, the bone grafts harvested from the fracture borders were used in the 10 favorable fractures and the bone grafts harvested from the iliac crest were used in the 14 unfavorable fractures. In the combined mandible fractures, four fractures were fixated with titanium plates and the other side with the bone graft. The patients, who were followed up for 12 to 20 months, were evaluated with macroscopic occlusion, panoramic graphs, and three-dimensional computerized tomographs. The advantage of this technique of fixation with the autogenous tissue is reduced infection rates and reduced operation costs. In the pediatric patients, the second session operation of plate removal is not necessary.

  6. Angular Stable Miniplate Fixation of Chronic Unstable Scaphoid Nonunion.

    Science.gov (United States)

    Schormans, Philip M J; Brink, Peter R G; Poeze, Martijn; Hannemann, Pascal F W

    2018-02-01

    Background  Around 5 to 15% of all scaphoid fractures result in nonunion. Treatment of long-lasting scaphoid nonunion remains a challenge for the treating surgeon. Healing of scaphoid nonunion is essential for prevention of scaphoid nonunion advanced collapse and the subsequent predictable pattern of radiocarpal osteoarthritis. Purpose  The purpose of this study was to investigate the feasibility of fixation of the scaphoid nonunion with a volar angular stable miniplate and cancellous bone grafting. We hypothesized that this technique could be successful, even in patients with previous surgery for nonunion and in patients with a long duration of nonunion. Patients and Methods  A total of 21 patients enrolled in a single-center prospective cohort study. Healing of nonunion was assessed on multiplanar computed tomography scan of the wrist at a 3-month interval. Functional outcome was assessed by measuring grip strength, range of motion, and by means of the patient-rated wrist and hand evaluation (PRWHE) questionnaire. Results  During follow-up, 19 out of 21 patients (90%) showed radiological healing of the nonunion. The range of motion did not improve significantly. Postoperative PRWHE scores decreased by 34 points. Healing occurred regardless of the length of time of the nonunion (range: 6-183 months) and regardless of previous surgery (38% of patients). Conclusion  Volar angular stable miniplate fixation with autologous cancellous bone grafting is a successful technique for the treatment of chronic unstable scaphoid nonunion, even in patients with long-lasting nonunion and in patients who underwent previous surgery for a scaphoid fracture. Rotational interfragmentary stability might be an important determining factor for the successful treatment of unstable scaphoid nonunion. Level of Evidence  Level IV.

  7. Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures

    Directory of Open Access Journals (Sweden)

    Rajasekhar Gali

    2016-01-01

    Full Text Available Introduction: Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. Purpose: This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. Patients and Methods: This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a the ease of access for retrieval, reimplantation and fixation of the proximal segment; b the postoperative approach related complications; c the adequacy of anatomical reduction and stability of fixation; d the occlusal changes; and the e TMJ function and radiological changes. Results: Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. Conclusion: The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby

  8. Evaluation of the syndesmotic-only fixation for Weber-C ankle fractures with syndesmotic injury.

    Science.gov (United States)

    Mohammed, R; Syed, S; Metikala, S; Ali, Sa

    2011-09-01

    With the length of the fibula restored and the syndesmosis reduced anatomically, internal fixation using a plating device may not be necessary for supra-syndesmotic fibular fractures combined with diastasis of inferior tibio-fibular joint. A retrospective observational study was performed in patients who had this injury pattern treated with syndesmosis-only fixation. 12 patients who had Weber type-C injury pattern were treated with syndesmosis only fixation. The treatment plan was followed only if the fibular length could be restored and if the syndesmosis could be anatomically reduced. Through a percutaneous or mini-open reduction and clamp stabilization of the syndesmosis, all but one patient had a single tricortical screw fixation across the syndesmosis. Patients were kept non-weight-bearing for 6 weeks, followed by screw removal at an average of 8 weeks. Outcomes were assessed using an objective ankle scoring system (Olerud and Molander scale) and by radiographic assessment of the ankle mortise. At a mean follow-up of 13 months, the functional outcome score was 75. Excellent to good outcomes were noted in 83% of the patients. Ankle mortise was reduced in all cases, and all but one fibular fracture united without loss of fixation. Six patients had more than one malleolar injury, needing either screw or anchor fixations. One patient had late diastasis after removal of the syndesmotic screw and underwent revision surgery with bone grafting of the fibula. This was probably due to early screw removal, before union of the fibular fracture had occurred. We recommend syndesmosis-only fixation as an effective treatment option for a combination of syndesmosis disruption and Weber type-C lateral malleolar fractures.

  9. Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures.

    Science.gov (United States)

    Gali, Rajasekhar; Devireddy, Sathya Kumar; Venkata, Kishore Kumar Rayadurgam; Kanubaddy, Sridhar Reddy; Nemaly, Chaithanyaa; Dasari, Mallikarjuna

    2016-01-01

    Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP) approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a) the ease of access for retrieval, reimplantation and fixation of the proximal segment; b) the postoperative approach related complications; c) the adequacy of anatomical reduction and stability of fixation; d) the occlusal changes; and the e) TMJ function and radiological changes. Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch) palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby permitting perpendicular placement of screws with minimal risk of damage to the facial

  10. ACL graft constructs: In-vitro fatigue testing highlights the occurrence of irrecoverable lengthening and the need for adequate (pre)conditioning to avert the recurrence of knee instability.

    Science.gov (United States)

    Blythe, A; Tasker, T; Zioupos, P

    2006-01-01

    The performance of ACL grafts in both the short and long term is only as good as the condition of the graft at the time of surgery. If the graft lengthens under load at the two fixation ends incorporation will take longer to occur. Previous studies have shown that the various grafts currently used are strong enough. However, data on strength came primarily from quasistatic single pull to failure tests with, in some cases, modest cycling to precondition the grafts. The present study examined the in-vitro biomechanical behaviour of model ACL grafts, which have been fatigue cycled to failure over a wide range of loads in physiological ambient conditions. Load/deformation curves and the stretch of the grafts was continuously recorded until final rupture. The grafts demonstrated typical creep-rupture like behaviour with elongation (non-recoverable stretch) and loss of stiffness leading to gradual failure. Some of the graft designs were consistently shown to elongate up to 20 mm in length within the first 2000 cycles at moderate physiological loads and a further 10 mm of elongation occurred between the initial preconditioned state and just prior to complete rupture. Not enough attention has been paid previously to the likely long term elongation patterns of ACL grafts post-surgery and even after the usual empirical preconditioning has been performed by the surgeon. Increased graft dimensions may result in recurrent knee instability and may also lead to failure of the graft to incorporate. Preconditioning in-vitro may still be a way to remove some slack and prepare the graft for its operational environment by stiffening in particular the tissue/fixation interface for those grafts that use soft polymer fixation ends.

  11. Haemodynamics in axillobifemoral bypass grafts

    NARCIS (Netherlands)

    C.H. Wittens

    1992-01-01

    textabstractThis thesis is based on four publications on the subject of graft configuration and haemodynamics in axillobifemoral bypass grafts: 1. A clinical evaluation of 17 patients with axillobifemoral bypass graft operations, performed for various indications. Two important observations were

  12. [Pedicle flap transfer combined with external fixator to treat leg open fracture with soft tissue defect].

    Science.gov (United States)

    Luo, Zhongchun; Lou, Hua; Jiang, Junwei; Song, Chunlin; Gong, Min; Wang, Yongcai

    2008-08-01

    To investigate the clinical results of treating leg open fracture with soft tissue defect by pedicle flap transfer in combination with external fixator. From May 2004 to June 2007, 12 cases of leg open fracture with soft tissue defect, 9 males and 3 females aged 18-75 years, were treated. Among them, 8 cases were caused by traffic accidents, 2 crush, 1 falling and 1 mechanical accident. According to the Gustilo Classification, there were 2 cases of type II, 5 of type IIIA and 5 of type IIIB. There were 2 cases of upper-tibia fracture, 3 of middle-tibia and 7 of middle-lower. The sizes of soft tissue defect ranged from 5 cm x 3 cm to 22 cm x 10 cm.The sizes of exposed bone ranged from 3 cm x 2 cm to 6 cm x 3 cm. The course of the disease was 1-12 hours. Fracture fixation was reached by external fixators or external fixators and limited internal fixation with Kirschner wire. The wounds with exposed tendons and bones were repaired by ipsilateral local rotation flap, sural neurocutaneous flap and saphenous nerve flap. The size of selected flap ranged from 5 cm x 4 cm to 18 cm x 12 cm. Granulation wounds were repaired by skin grafting or direct suture. All patients were followed up for 6 months to 2 years. All patients survived, among whom 2 with the wound edge infection and 1 with the distal necrosis were cured by changing the dressing, 8 with pin hole infection were treated by taking out the external fixator, 1 with nonunion received fracture healing after bone graft in comminuted fracture of lower tibia, 2 suffered delayed union in middle-lower tibia fracture. The ROM of ankle in 3 cases was mildly poor with surpass-joint fixation, with plantar extension of 0-10 degrees and plantar flexion of 10-30 degrees, while the others had plantar extension of 10-20 degrees and plantar flexion of 30-50 degrees. The method of pedicle flap transfer combined with external fixator is safe and effective for the leg open fracture with soft tissue defect.

  13. Primary renal graft thrombosis

    NARCIS (Netherlands)

    Bakir, N; Sluiter, WJ; Ploeg, RJ; van Son, WJ; Tegzess, Adam

    Background. Renal allograft thrombosis is a serious complication of kidney transplantation that ultimately leads to graft loss. Its association with acute and hyperacute rejection is well documented; however, in a large proportion of patients the precise cause remains obscure. The exact incidence

  14. Aortic Graft Infection Secondary to Iatrogenic Transcolonic Graft Malposition.

    Science.gov (United States)

    Blank, Jacqueline J; Rothstein, Abby E; Lee, Cheong Jun; Malinowski, Michael J; Lewis, Brian D; Ridolfi, Timothy J; Otterson, Mary F

    2018-01-01

    Aortic graft infections are a rare but devastating complication of aortic revascularization. Often infections occur due to contamination at the time of surgery. Iatrogenic misplacement of the limbs of an aortobifemoral graft is exceedingly rare, and principles of evaluation and treatment are not well defined. We report 2 cases of aortobifemoral bypass graft malposition through the colon. Case 1 is a 54-year-old male who underwent aortobifemoral bypass grafting for acute limb ischemia. He had previously undergone a partial sigmoid colectomy for diverticulitis. Approximately 6 months after vascular surgery, he presented with an occult graft infection. Preoperative imaging and intraoperative findings were consistent with graft placement through the sigmoid colon. Case 2 is a 60-year-old male who underwent aortobifemoral bypass grafting due to a nonhealing wound after toe amputation. His postoperative course was complicated by pneumonia, bacteremia thought to be secondary to the pneumonia, general malaise, and persistent fevers. Approximately 10 weeks after the vascular surgery, he presented with imaging and intraoperative findings of graft malposition through the cecum. Aortic graft infection is usually caused by surgical contamination and presents as an indolent infection. Case 1 presented as such; Case 2 presented more acutely. Both grafts were iatrogenically misplaced through the colon at the index operation. The patients underwent extra-anatomic bypass and graft explantation and subsequently recovered.

  15. Ilizarov bone transport versus fibular graft for reconstruction of tibial bone defects in children.

    Science.gov (United States)

    Abdelkhalek, Mostafa; El-Alfy, Barakat; Ali, Ayman M

    2016-11-01

    The aim of this study was to compare the results of treatment of segmental tibial defects in the pediatric age group using an Ilizarov external fixator versus a nonvascularized fibular bone graft. This study included 24 patients (age range from 5.5 to 15 years) with tibial bone defects: 13 patients were treated with bone transport (BT) and 11 patients were treated with a nonvascularized fibular graft (FG). The outcome parameters were bone results (union, deformity, infection, leg-length discrepancy) and functional results: external fixation index and external fixation time. In group A (BT), one patient developed refracture at the regenerate site, whereas, in group B (FG), after removal of the external fixator, one of the FGs developed a stress fracture. The external fixator time in group A was 10.7 months (range 8-14.5) versus 7.8 months (range 4-11.5 months) in group B (FG). In group A (BT), one patient had a limb-length discrepancy (LLD), whereas, in group B (FG), three patients had LLD. The functional and bone results of the Ilizarov BT technique were excellent in 23.1 and 30.8%, good in 38.5 and 46.2, fair in 30.8 and 15.4, and poor in 7.6 and 7.6%, respectively. The poor functional result was related to the poor bone result because of prolonged external fixator time resulting in significant pain, limited ankle motion, whereas the functional and bone results of fibular grafting were excellent in 9.1 and 18.2%, good in 63.6 and 45.5%, fair in 18.2 and 27.2%, and poor in 9.1 and 9.1%, respectively. Segmental tibial defects can be effectively treated with both methods. The FG method provides satisfactory results, with early removal of the external fixator. However, it had a limitation in patients with severe infection and those with LLD. Also, it requires a long duration of limb bracing until adequate hypertrophy of the graft. The Ilizarov method has the advantages of early weight bearing, treatment of postinfection bone defect in a one-stage surgery, and the

  16. The Use of Grafting to Study Systemic Signaling in Plants.

    Science.gov (United States)

    Tsutsui, Hiroki; Notaguchi, Michitaka

    2017-08-01

    Grafting has long been an important technique in agriculture. Nowadays, grafting is a widely used technique also to study systemic long-distance signaling in plants. Plants respond to their surrounding environment, and at that time many aspects of their physiology are regulated systemically; these start from local input signals and are followed by the transmission of information to the rest of the plant. For example, soil nutrient conditions, light/photoperiod, and biotic and abiotic stresses affect plants heterogeneously, and plants perceive such information in specific plant tissues or organs. Such environmental cues are crucial determinants of plant growth and development, and plants drastically change their morphology and physiology to adapt to various events in their life. Hitherto, intensive studies have been conducted to understand systemic signaling in plants, and grafting techniques have permitted advances in this field. The breakthrough technique of micrografting in Arabidopsis thaliana was established in 2002 and led to the development of molecular genetic tools in this field. Thereafter, various phenomena of systemic signaling have been identified at the molecular level, including nutrient fixation, flowering, circadian clock and defense against pathogens. The significance of grafting is that it can clarify the transmission of the stimulus and molecules. At present, many micro- and macromolecules have been identified as mobile signals, which are transported through plant vascular tissues to co-ordinate their physiology and development. In this review, we introduce the various grafting techniques that have been developed, we report on the recent advances in the field of plant systemic signaling where grafting techniques have been applied and provide insights for the future. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Overcoming fixation with repeated memory suppression.

    Science.gov (United States)

    Angello, Genna; Storm, Benjamin C; Smith, Steven M

    2015-01-01

    Fixation (blocks to memories or ideas) can be alleviated not only by encouraging productive work towards a solution, but, as the present experiments show, by reducing counterproductive work. Two experiments examined relief from fixation in a word-fragment completion task. Blockers, orthographically similar negative primes (e.g., ANALOGY), blocked solutions to word fragments (e.g., A_L_ _GY) in both experiments. After priming, but before the fragment completion test, participants repeatedly suppressed half of the blockers using the Think/No-Think paradigm, which results in memory inhibition. Inhibiting blockers did not alleviate fixation in Experiment 1 when conscious recollection of negative primes was not encouraged on the fragment completion test. In Experiment 2, however, when participants were encouraged to remember negative primes at fragment completion, relief from fixation was observed. Repeated suppression may nullify fixation effects, and promote creative thinking, particularly when fixation is caused by conscious recollection of counterproductive information.

  18. Mechanical-biological waste treatment and anaerobic processes. 59. information meeting, Neuwied, October 1999; Mechanisch-biologische Restabfallbehandlung und Anaerobverfahren. 59. Informationsgespraech in Neuwied im Oktober 1999

    Energy Technology Data Exchange (ETDEWEB)

    Hangen, H.O.; Euler, H.; Leonhardt, H.W. [comps.

    1999-10-01

    This proceedings volume discusses the specifications for and cost of mechanical-biological waste treatment, the optimisation of economic efficiency and pollutant emissons, the combination of mechanical-biological and thermal waste treatment processes, the value of mechanical-biological waste treatment, waste management concepts, process engineering and practical experience, and the eco-balance of the process. [German] Themen dieses Proceedingsbandes sind: Anforderungen und Kosten der mechanisch-biologischen Abfallbehandlung; Optimierung der Wirtschaftlichkeit und Emissionssituation; Kombination von mechanisch-biologischer und thermischer Muellbehandlung; Bewertung der mechanisch-biologischen Abfallbehandlung, Abfallwirtschaftskonzepte, Verfahrenstechnik und Betriebserfahrungen; Oekobilanz. (SR)

  19. Graft tendon slippage with metallic and bioabsorbable interference screws under cyclic load: a biomechanical study in a porcine model

    Directory of Open Access Journals (Sweden)

    Ari Digiácomo Ocampo Moré

    Full Text Available Introduction The rupture of the anterior cruciate ligament (ACL is the most common type of knee injury. Reconstructive surgery is the ‘gold standard’ treatment. During the immediate post-operative period, the fixation of the graft is entirely dependent on the ability of the grafted implant to be secured inside the bone tunnel under the cyclical loads associated with daily tasks. Poor fixation can lead to graft slippage, thus impairing the healing and integration of the graft. The aim of this study was to evaluate the biomechanical performance of tendon graft fixation devices with metallic and bioabsorbable interference screws. Methods Twenty ACL reconstructions were carried out in porcine tibias using deep flexor tendons to fix 9 × 20 mm metallic (n=10 and PLLA 70/30 bioabsorbable screws (n=10. To verify the ability of a construct to resist immediate postoperative (PO rehabilitation protocols for immediate load bearing, a cyclic loading test was applied with 50-250 N of tensile force at 1 Hz for 1000 cycles, and the displacement was measured at 10, 50, 100, 500 and 1000 load cycles to quantify the slippage of the graft during the test. After the cyclic loading test, a single-cycle load-to-failure test was applied. Results The slippage of the graft using metallic screws did not differ (P = 0.616 from that observed when using bioabsorbable screws. Conclusion The results obtained in this experiment indicate that metallic screws may promote a similar amount of graft slippage during low cyclic loading as bioabsorbable screws. Additionally, there was no difference in the biomechanical performance of these two types of screws during high failure loads.

  20. Polymeric media for tritium fixation. Supplement I

    International Nuclear Information System (INIS)

    Franz, J.A.; Burger, L.L.

    1976-01-01

    Procedures for the fixation of tritium as TH or THO in two different polymeric media are described. The complete procedure for THO fixation in a polyureylene-polyurethane polumer, including polymer molding procedures and leach tests is presented. The catalytic tritiation of polystyrene under very mild conditions using a rhodium catalyst is also described. Thermal stabilities and cost estimates for the polymers examined under this program are discussed. Organic polymers were found to have attractive features for the fixation and storage of concentrated tritium wastes due to the convenience of fixation procedures and favorable properties of the resulting media

  1. Modeling fixation locations using spatial point processes.

    Science.gov (United States)

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

    2013-10-01

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

  2. Methanotrophy induces nitrogen fixation during peatland development

    Science.gov (United States)

    Larmola, Tuula; Leppänen, Sanna M.; Tuittila, Eeva-Stiina; Aarva, Maija; Merilä, Päivi; Fritze, Hannu; Tiirola, Marja

    2014-01-01

    Nitrogen (N) accumulation rates in peatland ecosystems indicate significant biological atmospheric N2 fixation associated with Sphagnum mosses. Here, we show that the linkage between methanotrophic carbon cycling and N2 fixation may constitute an important mechanism in the rapid accumulation of N during the primary succession of peatlands. In our experimental stable isotope enrichment study, previously overlooked methane-induced N2 fixation explained more than one-third of the new N input in the younger peatland stages, where the highest N2 fixation rates and highest methane oxidation activities co-occurred in the water-submerged moss vegetation. PMID:24379382

  3. 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.

  4. Experimental and modelling studies on a laboratory scale anaerobic bioreactor treating mechanically biologically treated municipal solid waste.

    Science.gov (United States)

    Lakshmikanthan, P; Sughosh, P; White, James; Sivakumar Babu, G L

    2017-07-01

    The performance of an anaerobic bioreactor in treating mechanically biologically treated municipal solid waste was investigated using experimental and modelling techniques. The key parameters measured during the experimental test period included the gas yield, leachate generation and settlement under applied load. Modelling of the anaerobic bioreactor was carried out using the University of Southampton landfill degradation and transport model. The model was used to simulate the actual gas production and settlement. A sensitivity analysis showed that the most influential model parameters are the monod growth rate and moisture. In this case, pH had no effect on the total gas production and waste settlement, and only a small variation in the gas production was observed when the heat transfer coefficient of waste was varied from 20 to 100 kJ/(m d K) -1 . The anaerobic bioreactor contained 1.9 kg (dry) of mechanically biologically treated waste producing 10 L of landfill gas over 125 days.

  5. Stabilization of organic matter and nitrogen immobilization during mechanical-biological treatment and landfilling of residual municipal solid waste

    International Nuclear Information System (INIS)

    Heiss-Ziegler, C.

    2000-04-01

    Synthesis of humic substances and nitrogen immobilization during mechanical-biological treatment of waste and the behavior of biologically stabilized waste under anaerobic landfill conditions were investigated. Samples were taken from a large-scale treatment plant. Anaerobic conditions were simulated in lab scale test cells. Humic substances were analyzed photometrically and gravimetrically. The nitrogen immobilization was investigated by sequential leaching tests and by analyzing the non acid hydrolyzable nitrogen. Humic acids were mainly synthesized during the beginning of the intensive rotting phase. Later on in the process no significant changes occurred. The humic acid content rose up to 6,8 % DS org. It correlated well with the stability parameters respiration activity and accumulated gas production. In the coarse of the treatment the nitrogen load emitted during the consecutive leaching tests dropped from 50 % down to less than 20 % total nitrogen. The non acid hydrolyzable nitrogen rose from 17 up to 42 % Kjeldahl nitrogen content. Nevertheless the mechanical-biological treatment is not significantly shortening the aftercare period of a landfill concerning liquid nitrogen emissions. The reduced nitrogen emission potential is released more slowly. When reactive waste material was exposed to anaerobic conditions, humic and fulvic acids were synthesized up to the point when intensive gas production started and then were remineralized. Stabilized waste materials after treatment of various intensity behaved differently under anaerobic conditions. Steady and decreasing humic acid contents were observed. (author)

  6. [Comparison of external fixation with or without limited internal fixation for open knee fractures].

    Science.gov (United States)

    Li, K N; Lan, H; He, Z Y; Wang, X J; Yuan, J; Zhao, P; Mu, J S

    2018-03-01

    Objective: To explore the characteristics and methods of different fixation methods and prevention of open knee joint fracture. Methods: The data of 86 cases of open knee joint fracture admitted from January 2002 to December 2015 in Department of Orthopaedics, Affiliated Hospital of Chengdu University were analyzed retrospectively.There were 65 males and 21 females aged of 38.6 years. There were 38 cases treated with trans articular external fixation alone, 48 cases were in the trans articular external fixation plus auxiliary limited internal fixation group. All the patients were treated according to the same three stages except for different fixation methods. Observation of external fixation and fracture fixation, fracture healing, wound healing and treatment, treatment and related factors of infection control and knee function recovery. χ(2) test was used to analyze data. Results: Eleven patients had primary wound healing, accounting for 12.8%. Seventy-five patients had two wounds healed, accounting for 87.2%. Only 38 cases of trans articular external fixator group had 31 cases of articular surface reduction, accounting for 81.6%; Five cases of trans articular external fixator assisted limited internal fixation group had 5 cases of poor reduction, accounting for 10.4%; There was significant difference between the two groups (χ(2)=44.132, P external fixation group, a total of 23 cases of patients with infection, accounted for 60.5% of external fixation group; trans articular external fixation assisted limited internal fixation group there were 30 cases of patients with infection, accounting for the assistance of external fixator and limited internal fixation group 62.5%; There was significant difference between the two groups(χ(2)=0.035, P >0.05). Five cases of fracture nonunion cases of serious infection, patients voluntarily underwent amputation. The Lysholm Knee Scale: In the external fixation group, 23 cases were less than 50 points, accounting for 60

  7. Vein grafting in fingertip replantations.

    Science.gov (United States)

    Yan, Hede; Jackson, William D; Songcharoen, Somjade; Akdemir, Ovunc; Li, Zhijie; Chen, Xinglong; Jiang, Liangfu; Gao, Weiyang

    2009-01-01

    In this retrospective study, the survival rates of fingertip replantation with and without vein grafting were evaluated along with their postoperative functional and cosmetic results. One hundred twenty-one-fingertip amputations were performed in 103 patients between September 2002 and July 2007. Thirty-four amputated fingertips were replanted without vein grafting, while 87 amputated fingertips were replanted with vein grafting for arterial and/or venous repairs. The overall survival rates of the replantations with and without vein grafting were 90% (78/87) and 85% (29/34), respectively. The survival rates were 88% (36/41) with venous repair, 93% (25/27) with arterial repair, and 89% (17/19) with both. Nineteen patients without vein grafting and 48 patients with vein grafting had a follow-up period of more than one year. Good cosmetic and functional outcomes were observed in both groups of patients. The results show that vein grafting is a reliable technique in fingertip replantations, showing no significant difference (P > 0.05) in survival between those with and without vein grafting. Furthermore, no significant difference (P > 0.05) in survival was found between cases with vein grafts for arterial and/or venous repairs. In fingertip replantations with vein grafting, favorable functional and esthetic results can be achieved without sacrificing replantation survival. (c) 2009 Wiley-Liss, Inc.

  8. Outcome of 28 open pilon fractures with injury severity-based fixation.

    Science.gov (United States)

    Danoff, Jonathan R; Saifi, Comron; Goodspeed, David C; Reid, J Spence

    2015-04-01

    Open pilon fracture management and treatment poses a significant challenge to orthopedic surgeons. The purpose of this study was to determine patient outcomes for open pilon fractures based on wound complication and infection rates, as well as subjective outcome instruments. This was a retrospective consecutive case series of 28 fractures with Orthopaedic Trauma Association (OTA)-type 43-B and 43-C open pilon fractures. Mean length of follow-up was 36 months and minimum of 1 year. Ten fractures were Gustilo and Anderson grade IIIB, and the remaining fractures were grades I-IIIA. Patients were initially treated with spanning external fixation and staged wound debridement followed by osteosynthesis of the articular surface. Metaphyseal fixation was by either plate fixation or Ilizarov frame. The primary outcome was the incidence of deep tissue infection requiring surgery. Secondary outcomes included the incidence of other complications (nonunion, malunion, amputation) and functional outcomes (Short Musculoskeletal Functional Assessment Questionnaire and AAOS Foot and Ankle Questionnaire). Four patients developed deep tissue infections, three in the internal fixation group and one in the Ilizarov group, and all were treated successfully with staged debridement. There were two delayed unions required bone grafting, and infection-free union was ultimately achieved in all fractures. Two patients underwent arthrodesis secondary to post-traumatic arthritis, while no patients experienced malunions or amputations. The use of staged wound debridement in conjunction with either plate fixation or Ilizarov frame achieves low rates of wound infection and stable fixation after anatomic joint reconstruction for OTA-type 43-B and 43-C open pilon fractures.

  9. Improper tube fixation causing a leaky cuff

    Directory of Open Access Journals (Sweden)

    Gupta Babita

    2010-01-01

    Full Text Available Leaking endotracheal tube cuffs are common problems in intensive care units. We report a case wherein the inflation tube was damaged by the adhesive plaster used for tube fixation and resulted in leaking endotracheal tube cuff. We also give some suggestions regarding the tube fixation and some remedial measures for damaged inflation system.

  10. Nitrogen fixation by legumes in retorted shale

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L E; Molitoris, E; Klein, D A

    1981-01-01

    A study was made to determine whether retorted shale additions would significantly affect symbiotic N/sub 2/ fixation. Results indicate that small additions of the shale may stimulate plant growth but with higher concentrations plants are stressed, resulting in a decreased biomass and a compensatory effect of an increased number of nodules and N/sub 2/ fixation potential. (JMT)

  11. Outcome of rail fixator system in reconstructing bone gap

    Directory of Open Access Journals (Sweden)

    Amit Lakhani

    2014-01-01

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

  12. EFFECT OF EMBEDDING METHODS VERSUS FIXATIVE TYPE ON KARYOMETRIC MEASURES

    NARCIS (Netherlands)

    BOON, ME; VANDERPOEL, HG; TAN, CJA; KOK, LP

    The influence of fixation and embedding methods in seven urologic tumor samples was studied karyometrically for 12 preparatory techniques. Routine histologic formalin fixation was compared with Carbowax and Kryofix fixatives. Also, histologic material was studied embedded in paraffin and plastic

  13. Successful fifth metatarsal bulk autograft reconstruction of thermal necrosis post intramedullary fixation.

    Science.gov (United States)

    Veljkovic, Andrea; Le, Vu; Escudero, Mario; Salat, Peter; Wing, Kevin; Penner, Murray; Younger, Alastair

    2018-03-21

    Reamed intramedullary (IM) screw fixation for proximal fifth metatarsal fractures is technically challenging with potentially devastating complications if basic principles are not followed. A case of an iatrogenic fourth-degree burn after elective reamed IM screw fixation of a proximal fifth metatarsal fracture in a high-level athlete is reported. The case was complicated by postoperative osteomyelitis with third-degree soft-tissue defect. This was successfully treated with staged autologous bone graft reconstruction, tendon reconstruction, and local bi-pedicle flap coverage. The patient returned to competitive-level sports, avoiding the need for fifth ray amputation. Critical points of the IM screw technique and definitive reconstruction are discussed. Bulk autograft reconstruction is a safe and effective alternative to ray amputation in segmental defects of the fifth metatarsal.Level of evidence V.

  14. Eighth international congress on nitrogen fixation. Final program

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

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

  15. Meeting the specifications for mechanical-biological waste treament and dumping; Umsetzung der Ablagerungsanforderungen im MBA- und Deponiebetrieb

    Energy Technology Data Exchange (ETDEWEB)

    Ketelsen, K. [IBA Ingenieurbuero fuer Abfallwirtschaft und Entsorgung GmbH, Hannover (Germany)

    2001-07-01

    The new German ordinances will have a dramatic influence on the waste treatment processes and air/exhaust management in mechanical-biological waste treatment plants. The potentials of process control and optimization should be fully utilized. The extensive in-service inspections and specifications will change the requirements on the process and staff qualification. The additional cost must be balanced by technically and economically feasible projecting and solutions. The need to keep up with thermal processes will lead to the construction of plants with a size of 50,000 Mg/a and more as these have higher economic efficiency, i.e. small regional utilities will have to co-operate. In mechanical-biological waste treatment plants, about 40-50% of the total cost is accounted for by the waste treatment process, i.e. economic efficiency will depend on the cost of dumping of the stabilized fine-grained fraction(about 20%) and the cost of utilization of the high-calorific waste (about 30%). In view of the high fixed cost, mechanical-biological waste treatment concepts will be economically efficient only if the plant capacity is fully utilized. [German] Mit Verabschiedung der Verordnungen ist die MBA 'gesellschaftsfaehiger' geworden. Die Verordnungen werden einen nachhaltigen Einfluss auf die Verfahrenstechnik und das gesamte Luft-/Abgasmanagement haben. Die Entwicklungspotentiale in der Prozesssteuerung und -optimierung muessen verstaerkt ausgeschoepft werden. Durch die geforderten umfangreichen Untersuchungs- und Nachweispflichten werden sich die Anforderungen an die Betriebsfuehrung und Personalqualifikation veraendern. Die aus den hoeheren Anforderungen resultierenden Mehrkosten muessen durch technisch und wirtschftlich sinnvolle Planungen und Loesungen in vertretbaren Grenzen gehalten werden. Die Notwendigkeit zur Wirtschaftlichkeit im Wettbewerb mit rein thermischen Verfahren wird auch bei den MBA zur Realisierung wirtschaftlicher Anlagengroessen von groesser

  16. Polymeric media for tritium fixation

    International Nuclear Information System (INIS)

    Franz, J.A.; Burger, L.L.

    1975-01-01

    The synthesis and leach testing of several polymeric media for tritium fixation are presented. Tritiated bakelite, poly(acrylonitrile) and polystyrene successfully fixed tritium. Tritium leach rates at the tracer level appear to be negligible. Advantages and disadvantages of the processes are discussed, and further bench-scale investigations underway are reported. Rough cost estimates are presented for the different media and are compared with alternate approaches such as deep-well injection and long-term tank storage. Polymeric media costs are high compared to deep-well storage and are of the same order of magnitude per liter of water as for isotopic enrichment. With this limitation, polymeric media can be economically feasible only for highly concentrated tritiated wastes. It is recommended that the bakelite and polystyrene processes be examined on a larger scale to permit more accurate cost analysis and process design. (auth)

  17. Radionuclide fixation mechanisms in rocks

    International Nuclear Information System (INIS)

    Nakashima, S.

    1991-01-01

    In the safety evaluation of the radioactive waste disposal in geological environment, the mass balance equation for radionuclide migration is given. The sorption of radionuclides by geological formations is conventionally represented by the retardation of the radionuclides as compared with water movement. In order to quantify the sorption of radionuclides by rocks and sediments, the distribution ratio is used. In order to study quantitatively the long term behavior of waste radionuclides in geological environment, besides the distribution ratio concept in short term, slower radionuclide retention reaction involving mineral transformation should be considered. The development of microspectroscopic method for long term reaction path modeling, the behavior of iron during granite and water interaction, the reduction precipitation of radionuclides, radionuclide migration pathways, and the representative scheme of radionuclide migration and fixation in rocks are discussed. (K.I.)

  18. Vascular graft infections with Mycoplasma

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Skov Jensen, J; Prag, J

    1995-01-01

    laboratory techniques, the percentage of culture-negative yet grossly infected vascular grafts seems to be increasing and is not adequately explained by the prior use of antibiotics. We have recently reported the first case of aortic graft infection with Mycoplasma. We therefore suggest the hypothesis...... that the large number of culture-negative yet grossly infected vascular grafts may be due to Mycoplasma infection not detected with conventional laboratory technique....

  19. Environmental application of radiation grafting

    International Nuclear Information System (INIS)

    Tamada, Masao

    2007-01-01

    Adsorbent having high selectivity against a certain metal ion was synthesized by means of radiation-induced graft polymerization for the purpose of environmental application. The resulting adsorbents were utilized for the removal of toxic metal from scallop waste and the collection of uranium from seawater. As a novel application of grafting, the biodegradability of poly-hydroxybutylate was controlled by grafting. The biodegradability could be depressed by the graft chain and then recovered by external stimuli such as thermal and chemical treatments. (author)

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2008-09-01

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

  2. Dinitrogen fixation in aphotic oxygenated marine environments

    Directory of Open Access Journals (Sweden)

    Eyal eRahav

    2013-08-01

    Full Text Available We measured N2 fixation rates from oceanic zones that have traditionally been ignored as sources of biological N2 fixation; the aphotic, fully oxygenated, nitrate (NO3--rich, waters of the oligotrophic Levantine Basin (LB and the Gulf of Aqaba (GA. N2 fixation rates measured from pelagic aphotic waters to depths up to 720 m, during the mixed and stratified periods, ranged from 0.01 nmol N L-1 d-1 to 0.38 nmol N L-1 d-1. N2 fixation rates correlated significantly with bacterial productivity and heterotrophic diazotrophs were identified from aphotic as well as photic depths. Dissolved free amino acid amendments to whole water from the GA enhanced bacterial productivity by 2to 3.5 and N2 fixation rates by ~ 2 fold in samples collected from aphotic depths while in amendments to water from photic depths bacterial productivity increased 2 to 6 fold while N2 fixation rates increased by a factor of 2 to 4 illustrating that both BP an heterotrophic N2 fixation are carbon limited. Experimental manipulations of aphotic waters from the LB demonstrated a significant positive correlation between transparent exopolymeric particles (TEP concentration and N2 fixation rates. This suggests that sinking organic material and high carbon (C: nitrogen (N micro-environments (such as TEP-based aggregates or marine snow could support high heterotrophic N2 fixation rates in oxygenated surface waters and in the aphotic zones. Indeed, our calculations show that aphotic N2 fixation accounted for 37 to 75 % of the total daily integrated N2 fixation rates at both locations in the Mediterranean and Red Seas with rates equal or greater to those measured from the photic layers. Moreover, our results indicate that that while N2 fixation may be limited in the surface waters, aphotic, pelagic N2 fixation may contribute significantly to new N inputs in other oligotrophic basins, yet it is currently not included in regional or global N budgets.

  3. Is the internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? A systematic review.

    Science.gov (United States)

    Goiato, Marcelo Coelho; Pellizzer, Eduardo Piza; da Silva, Emily Vivianne Freitas; Bonatto, Liliane da Rocha; dos Santos, Daniela Micheline

    2015-09-01

    This systematic review aimed to evaluate if the internal connection is more efficient than the external connection and its associated influencing factors. A specific question was formulated according to the Population, Intervention, Control, and Outcome (PICO): Is internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? An electronic search of the MEDLINE and the Web of Knowledge databases was performed for relevant studies published in English up to November 2013 by two independent reviewers. The keywords used in the search included a combination of "dental implant" and "internal connection" or "Morse connection" or "external connection." Selected studies were randomized clinical trials, prospective or retrospective studies, and in vitro studies with a clear aim of investigating the internal and/or external implant connection use. From an initial screening yield of 674 articles, 64 potentially relevant articles were selected after an evaluation of their titles and abstracts. Full texts of these articles were obtained with 29 articles fulfilling the inclusion criteria. Morse taper connection has the best sealing ability. Concerning crestal bone loss, internal connections presented better results than external connections. The limitation of the present study was the absence of randomized clinical trials that investigated if the internal connection was more efficient than the external connection. The external and internal connections have different mechanical, biological, and esthetical characteristics. Besides all systems that show proper success rates and effectiveness, crestal bone level maintenance is more important around internal connections than external connections. The Morse taper connection seems to be more efficient concerning biological aspects, allowing lower bacterial leakage and bone loss in single implants, including aesthetic regions. Additionally, this connection type can be successfully

  4. Grafting the alar rim: application as anatomical graft.

    Science.gov (United States)

    Gruber, Ronald P; Fox, Paige; Peled, Anne; Belek, Kyle A

    2014-12-01

    Alar rim contour and alar rim grafts have become essential components of rhinoplasty. Ideally, grafts of the nose should be anatomical in shape. So doing might make grafts of the alar rim more robust. The authors considered doing that by applying the graft as a continuous extension of the lateral crus. Twelve patients (two men and 10 women) constituted the study group (seven primary and five secondary cases). Of those, there were five concave rims, two concave rims with rim retraction, two boxy tips, and three cephalically oriented lateral crura. Surgical technique included the following: (1) an open approach was used; (2) a marginal incision that ignored the caudal margin of the lateral crus (the incision went straight posteriorly to a point 5 to 6 mm from the rim margin) was used; (3) a triangular graft was made to cover the exposed vestibular skin; (4) it was secured end to end to the caudal border of the lateral crus; and (5) the poster end was allowed to sit in a small subcutaneous pocket. Follow-up was 11 to 19 months. All 12 patients exhibited good rims as judged by a blinded panel. Rim retraction was not fully corrected in one patient, but no further treatment was required. One patient did require a secondary small rim graft for residual rim concavity. The concept of grafting the alar rim is strongly supported by the authors' results. The modifications the authors applied by designing the graft to be anatomical in shape has been a technical help.

  5. Immaturity of Visual Fixations in Dyslexic Children.

    Directory of Open Access Journals (Sweden)

    TIADI eBi Kuyami Guy Aimé

    2016-02-01

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

  6. Sutureless Intrascleral Fixated Intraocular Lens Implantation.

    Science.gov (United States)

    Karadag, Remzi; Celik, Haci Ugur; Bayramlar, Huseyin; Rapuano, Christopher J

    2016-08-01

    To review sutureless intrascleral intraocular lens (IOL) fixation methods. Review of published literature. Sutureless intrascleral IOL fixation methods are newer and have been developed to eliminate the suture-related complications of sutured scleral fixation methods such as suture-induced inflammation or infection and IOL dislocation or subluxation due to suture degradation or suture breakage. Sutureless intrascleral fixation methods aim for intrascleral haptic fixation to achieve stability of the IOL. Various methods of sutureless scleral fixation have been described. Using a needle, a blade, or a trochar, sclerostomies are created in all techniques for intraocular access. Some surgeons prefer to create scleral tunnels, whereas others use scleral flaps for scleral fixation of haptics. The stability of IOLs is attained by the scar tissue formed around the haptics. Short-term results of these new methods are acceptable; studies including more cases with longer follow-up are needed to determine their long-term success. [J Cataract Refract Surg. 2016;32(9):586-597.]. Copyright 2016, SLACK Incorporated.

  7. Suction blister grafting - Modifications for easy harvesting and grafting

    Directory of Open Access Journals (Sweden)

    2012-01-01

    Full Text Available Suction blister grafting is a simple modality of treatment of patients with resistant and stable vitiligo. But raising the blisters may be time consuming and transferring to the recipient site may be difficult as the graft is ultrathin. By doing some modifications we can make the technique simpler and easier. We can decrease the blister induction time by intradermal injection of saline, exposure to Wood′s lamp, intrablister injection of saline. By these methods we can decrease the blister induction time from 2-3 hrs to 45-90 minutes. After harvesting the graft, it can be transferred to the recipient area by taking the graft on a sterile glass slide, on the gloved finger, rolling the graft over a sterile syringe and then spreading on the recipient area, or taking on the sterile wrapper of paraffin dressing and then placing over the recipient area.

  8. 14CO2 fixation pattern of cyanobacteria

    International Nuclear Information System (INIS)

    Erdmann, N.; Schiewer, U.

    1985-01-01

    The 14 CO 2 fixation pattern of three cyanobacteria in the light and dark were studied. Two different chromatographic methods widely used for separating labelled photosynthetic intermediates were compared. After ethanolic extraction, a rather uniform fixation pattern reflecting mainly the β-carboxylation pathway is obtained for all 3 species. Of the intermediates, glucosylglycerol is specific and high citrulline and low malate contents are fairly specific to cyanobacteria. The composition of the 14 CO 2 fixation pattern is hardly affected by changes in temperature or light intensity, but it is severely affected by changes in the water potential of the medium. (author)

  9. Carbon dioxide fixation in isolated Kalanchoe chloroplasts

    Energy Technology Data Exchange (ETDEWEB)

    Levi, C.; Gibbs, M.

    1975-07-01

    Chloroplasts isolated from Kalanchoe diagremontiana leaves were capable of photosynthesizing at a rate of 5.4 ..mu..moles of CO/sub 2/ per milligram of chlorophyll per hour. The dark rate of fixation was about 1 percent of the light rate. A high photosynthetic rate was associated with low starch content of the leaves. Ribose 5-phosphate, fructose 1, 6-diphosphate, and dithiothreitol stimulated fixation, whereas phosphoenolpyruvate and azide were inhibitors. The products of CO/sub 2/ fixation were primarily those of the photosynthetic carbon reduction cycle. (auth)

  10. Early prophylactic autogenous bone grafting in type III open tibial fractures.

    Science.gov (United States)

    Kesemenli, Cumhur C; Kapukaya, Ahmet; Subaşi, Mehmet; Arslan, Huseyin; Necmioğlu, Serdar; Kayikçi, Cuma

    2004-08-01

    The authors report the results achieved in patients with type III open tibial fractures who underwent primary autogenous bone grafting at the time of debridement and skeletal stabilisation. Twenty patients with a mean age of 35.8 years (range, 24-55) were treated between 1996 and 1999. Eight fractures were type IIIA, 11 were type IIIB, and 1 was type IIIC. At the index procedure, wound debridement, external fixation and autogenous bone grafting with bone coverage were achieved. The mean follow-up period was 46 months (range, 34-55). The mean time to fixator removal was 21 weeks (range, 14-35), and the mean time to union was 28 weeks (range, 19-45). Skin coverage was achieved by a myocutaneous flap in 2 patients, late primary closure in 4, and split skin grafting in 14. One (5%) of the patients experienced delayed union, and 1 (5%) developed infection. In tibial type III open fractures, skin coverage may be delayed, using the surrounding soft tissue to cover any exposed bone after thorough débridement and wound cleansing. Primary prophylactic bone grafting performed at the same time reduces the rate of delayed union, shortens the time to union, and does not increase the infection rate.

  11. SOME TECHNIQUES IN CORNEAL GRAFTING

    African Journals Online (AJOL)

    1971-04-10

    Apr 10, 1971 ... current herpes corneae. The visual acuity was less than. 6/60. The left eye had had a central nebula since child- hood and was deemed amblyopic. Six weeks after a 7 x 0·3 mm lamellar graft in the right eye was placed, ulceration occurred in the graft junction. A total thin conjunctival flap was sutured over.

  12. Polyether/Polyester Graft Copolymers

    Science.gov (United States)

    Bell, Vernon L., Jr.; Wakelyn, N.; Stoakley, D. M.; Proctor, K. M.

    1986-01-01

    Higher solvent resistance achieved along with lower melting temperature. New technique provides method of preparing copolymers with polypivalolactone segments grafted onto poly (2,6-dimethyl-phenylene oxide) backbone. Process makes strong materials with improved solvent resistance and crystalline, thermally-reversible crosslinks. Resulting graft copolymers easier to fabricate into useful articles, including thin films, sheets, fibers, foams, laminates, and moldings.

  13. [Effectiveness comparison of suspension fixation plus hinged external fixator and double plate internal fixation in treatment of type C humeral intercondylar fractures].

    Science.gov (United States)

    Zhang, Jian; Lin, Xu; Zhong, Zeli; Wu, Chao; Tan, Lun

    2017-07-01

    To compare the effectiveness of suspension fixation plus hinged external fixator with double plate internal fixation in the treatment of type C humeral intercondylar fractures. Between January 2014 and April 2016, 30 patients with type C (Association for the Study of Internal Fixation, AO/ASIF) humeral intercondylar fractures were treated. Kirschner wire suspension fixation plus hinged external fixator was used in 14 cases (group A), and double plate internal fixation in 16 cases (group B). There was no significant difference in gender, age, injury cause, disease duration, injury side, and type of fracture between 2 groups ( P >0.05). There was no significant difference in operation time and hospitalization stay between 2 groups ( P >0.05). But the intraoperative blood loss in group A was significantly less than that in group B ( P internal fixation removal, the intraoperative blood loss, and VAS score at 1 day and 3 days after operation in group A were significant better than those in group B ( P external fixator and double plate internal fixation for the treatment of type C humeral intercondylar fractures have ideal outcome in elbow function. But the suspension fixation plus hinged external fixator is better than double plate internal fixation in intraoperative blood loss, postoperative VAS score, and time of internal fixation removal.

  14. Radiation grafting on natural films

    Science.gov (United States)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  15. A tricalcium phosphate/polyether ether ketone anchor bionic fixation device for anterior cruciate ligament reconstruction: Safety and efficacy in a beagle model.

    Science.gov (United States)

    Mao, Genwen; Qin, Zili; Li, Zheng; Li, Xiang; Qiu, Yusheng; Bian, Weiguo

    2018-05-02

    The goal of this study was to develop a bionic fixation device based on the use of a tricalcium phosphate/polyether ether ketone anchor and harvesting of the ulnar carpal flexor muscle tendon for application as a ligament graft in a beagle anterior cruciate ligament (ACL) reconstruction model, with the goal of accelerating the ligament graft-to-bone tunnel healing and providing a robust stability through exploration of this new kind of autologous ligament graft. The safety and efficacy of this fixation device were explored 3 and 6 months after surgery in a beagle ACL reconstruction model using biomechanical tests and comprehensive histological observation. The data were compared using a two-tailed Student's t test and a paired t test. A p value <0.05 was defined as statistically significant. All the models were successfully established. This fixation device possessed the excellent mechanical properties for ACL reconstruction. A comprehensive histological observation revealed that a cartilage layer was visible in the transition zone between the tendon and bone interface at both 3 and 6 months postoperation. The trabecular of the new bone was observed six months after surgery and was found to be similar to a direct connection. This fixation technique provided not only a robust primary mechanical fixation but also a bionic fixation for long-term knee joint stability by accelerating the healing of the tendon to the bone tunnel, showing a high potential for use in clinical practice. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018. © 2018 Wiley Periodicals, Inc.

  16. Fixation probability on clique-based graphs

    Science.gov (United States)

    Choi, Jeong-Ok; Yu, Unjong

    2018-02-01

    The fixation probability of a mutant in the evolutionary dynamics of Moran process is calculated by the Monte-Carlo method on a few families of clique-based graphs. It is shown that the complete suppression of fixation can be realized with the generalized clique-wheel graph in the limit of small wheel-clique ratio and infinite size. The family of clique-star is an amplifier, and clique-arms graph changes from amplifier to suppressor as the fitness of the mutant increases. We demonstrate that the overall structure of a graph can be more important to determine the fixation probability than the degree or the heat heterogeneity. The dependence of the fixation probability on the position of the first mutant is discussed.

  17. Fixation of Selenium by Clay Minerals and Iron Oxides

    DEFF Research Database (Denmark)

    Hamdy, A. A.; Nielsen, Gunnar Gissel

    1977-01-01

    In studying Se fixation, soil components capable of retaining Se were investigated. The importance of Fe hydrous oxides in the fixation of Se was established. The clay minerals common to soils, such as kaolinite, montmorillonite and vermiculite, all exhibited Se fixation, but greater fixation occ...

  18. Posterior treatment of delayed traumatic atlantoaxial joint dislocation with apofix internal fixation

    International Nuclear Information System (INIS)

    Qing Wei; Jiang Weimin; Shi Jinhui; Li Xuefeng; Yang Huilin; Tang Tiansi

    2010-01-01

    Objective: To assess the effect of posterior fixation and fusion with Apofix device for the treatment of delayed traumatic atlantoaxial joint dislocation. Methods: Eighteen patients with delayed traumatic atlantoaxial joint dislocation were included. Posterior fixation and fusion with Apofix device were performed. First step was one or two week skull traction. After the atlantoaxial joint dislocation had been reduced, the posterior fixation and fusion with Apofix was performed. Using local anaesthesia, atlantoaxial interval and posterior structure of atlas and dentata were exposed by midline operative approach. Apofix interlaminar clamps were placed at posterior arch of atlas and odontoid vertebral laminae, autologous iliac bone graft was placed for fusion. Then the device to proper position was pressurized and items locked. Results: All of the patients were followed up, the mean follow-up period was 38 months (13 ∼ 84 months). Fifteen patients obtained complete reduction, the others were partial reduction. Seventeen patients had successful fusion after 3 or 4 months, only 1 patient who had partial reduction had internal fixation loose and nonfusion, leading to recurrence of atlantoaxial joint dislocation. An occipitocervical fusion surgery was performed on this patient. As to neurological assessment, 16 patients had neurological deficit before operation, while 6 of them recovered completely after operation, another 10 patients' neurological status improved significantly. JOA score was improved from 9.5 pre-operative to 15.8 post-operative. Conclusion: Apofix internal fixation and fusion seems to be feasible in treatment of delayed traumatic atlantoaxial joint dislocation. Successful reduction before operation and proper treatment after operation is also important. (authors)

  19. Biomechanical Evaluation of Standard Versus Extended Proximal Fixation Olecranon Plates for Fixation of Olecranon Fractures.

    Science.gov (United States)

    Boden, Allison L; Daly, Charles A; Dalwadi, Poonam P; Boden, Stephanie A; Hutton, William C; Muppavarapu, Raghuveer C; Gottschalk, Michael B

    2018-01-01

    Small olecranon fractures present a significant challenge for fixation, which has resulted in development of plates with proximal extension. Olecranon-specific plates with proximal extensions are widely thought to offer superior fixation of small proximal fragments but have distinct disadvantages: larger dissection, increased hardware prominence, and the increased possibility of impingement. Previous biomechanical studies of olecranon fracture fixation have compared methods of fracture fixation, but to date there have been no studies defining olecranon plate fixation strength for standard versus extended olecranon plates. The purpose of this study is to evaluate the biomechanical utility of the extended plate for treatment of olecranon fractures. Sixteen matched pairs of fresh-frozen human cadaveric elbows were used. Of the 16, 8 matched pairs received a transverse osteotomy including 25% and 8 including 50% of the articular surface on the proximal fragment. One elbow from each pair was randomly assigned to a standard-length plate, and the other elbow in the pair received the extended-length plate, for fixation of the fracture. The ulnae were cyclically loaded and subsequently loaded to failure, with ultimate load, number of cycles, and gap formation recorded. There was no statistically significant difference between the standard and extended fixation plates in simple transverse fractures at either 25% or 50% from the proximal most portion of the articular surface of the olecranon. Standard fixation plates are sufficient for the fixation of small transverse fractures, but caution should be utilized particularly with comminution and nontransverse fracture patterns.

  20. Maxwellian Eye Fixation during Natural Scene Perception

    Directory of Open Access Journals (Sweden)

    Jean Duchesne

    2012-01-01

    Full Text Available When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell’s law for each participant and for each scene condition (normal or scrambled. The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes.

  1. Variable Nitrogen Fixation in Wild Populus.

    Directory of Open Access Journals (Sweden)

    Sharon L Doty

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

  2. Maxwellian Eye Fixation during Natural Scene Perception

    Science.gov (United States)

    Duchesne, Jean; Bouvier, Vincent; Guillemé, Julien; Coubard, Olivier A.

    2012-01-01

    When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF) of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell's law for each participant and for each scene condition (normal or scrambled). The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes. PMID:23226987

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

    Directory of Open Access Journals (Sweden)

    Mrázek M.

    2010-07-01

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

  4. Graft intolerance syndrome requiring graft nephrectomy after late kidney graft failure: can it be predicted? A retrospective cohort study.

    Science.gov (United States)

    Bunthof, Kim L W; Verhoeks, Carmen M; van den Brand, Jan A J G; Hilbrands, Luuk B

    2018-02-01

    Graft nephrectomy is recommended in case of early graft failure. When the graft fails more than 3-6 months after transplantation, it is current practice to follow a wait-and-see policy. A common indication for graft removal is the graft intolerance syndrome. We aimed to create a risk prediction model for the occurrence of graft intolerance resulting in graft nephrectomy. We collected data of kidney transplantations performed in our center between 1980 and 2010 that failed at least 6 months after transplantation. We evaluated the association between baseline characteristics and the occurrence of graft nephrectomy because of graft intolerance using a competing risk regression model. Prognostic factors were included in a multivariate prediction model. In- and exclusion criteria were met in 288 cases. In 48 patients, the graft was removed because of graft intolerance. Donor age, the number of rejections, and shorter graft survival were predictive factors for graft nephrectomy because of the graft intolerance syndrome. These factors were included in a prediction rule. Using donor age, graft survival, and the number of rejections, clinicians can predict the need for graft nephrectomy with a reasonable accuracy. © 2017 Steunstichting ESOT.

  5. Nitrogen fixation in trees - 1

    Energy Technology Data Exchange (ETDEWEB)

    Dobereiner, J.; Gauthier, D.L.; Diem, H.G.; Dommergues, Y.R.; Bonetti, R.; Oliveira, L.A.; Magalhaes, F.M.M.; Faria, S.M. de; Franco, A.A.; Menandro, M.S.

    1984-01-01

    Six papers are presented from the symposium. Dobereiner, J.; Nodulation and nitrogen fixation in leguminous trees, 83-90, (15 ref.), reviews studies on Brazilian species. Gauthier, D.L., Diem, H.G., Dommergues, Y.R., Tropical and subtropical actinorhizal plants, 119-136, (Refs. 50), reports on studies on Casuarinaceae. Bonetti, R., Oliveira, L.A., Magalhaes, F.M.M.; Rhizobium populations and occurrence of VA mycorrhizae in plantations of forest trees, 137-142, (Refs. 15), studies Amazonia stands of Cedrelinga catenaeformis, Calophyllum brasiliense, Dipteryx odorata, D. potiphylla, Carapa guianensis, Goupia glabra, Tabebuia serratifolia, Clarisia racemosa, Pithecellobium racemosum, Vouacapoua pallidior, Eperua bijuga, and Diplotropis species. Nodulation was observed in Cedrelinga catenaeformis and V. pallidior. Faria, S.M. de, Franco, A.A., Menandro, M.S., Jesus, R.M. de, Baitello, J.B.; Aguiar, O.T. de, Doebereiner, J; survey of nodulation in leguminous tree species native to southeastern Brazil, 143-153, (Refs. 7), reports on 119 species, with first reports of nodulation in the genera Bowdichia, Poecilanthe, Melanoxylon, Moldenhaurea (Moldenhawera), and Pseudosamanea. Gaiad, S., Carpanezzi, A.A.; Occurrence of Rhizobium in Leguminosae of silvicultural interest for south Brazil, 155-158, (Refs. 2). Nodulation is reported in Mimosa scabrella, Acacia mearnsii, A. longifolia various trinervis, Enterolobium contortisiliquum, and Erythrina falcata. Magalhaes, L.M.S., Blum, W.E.H., Nodulation and growth of Cedrelinga catanaeformis in experimental stands in the Manaus region - Amazonas, 159-164, (Refs. 5). Results indicate that C. catenaeformis can be used in degraded areas of very low soil fertility.

  6. Cartilage grafting in nasal reconstruction.

    Science.gov (United States)

    Immerman, Sara; White, W Matthew; Constantinides, Minas

    2011-02-01

    Nasal reconstruction after resection for cutaneous malignancies poses a unique challenge to facial plastic surgeons. The nose, a unique 3-D structure, not only must remain functional but also be aesthetically pleasing to patients. A complete understanding of all the layers of the nose and knowledge of available cartilage grafting material is necessary. Autogenous material, namely septal, auricular, and costal cartilage, is the most favored material in a free cartilage graft or a composite cartilage graft. All types of material have advantages and disadvantages that should guide the most appropriate selection to maximize the functional and cosmetic outcomes for patients. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Inheritance of graft compatibility in Douglas fir.

    Science.gov (United States)

    D.L. Copes

    1973-01-01

    Graft compatibility of genetically related and unrelated rootstock-scion combinations was compared. Scion clones were 75% compatible when grafted on half-related rootstocks but only 56% compatible when grafted on unrelated rootstocks. Most variance associated with graft incompatibility in Douglas-fir appears to be caused by multiple genes.

  8. Graft union formation in Douglas-fir.

    Science.gov (United States)

    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  9. Fat Grafting for Facial Filling and Regeneration.

    Science.gov (United States)

    Coleman, Sydney R; Katzel, Evan B

    2015-07-01

    Plastic surgeons have come to realize that fat grafting can rejuvenate an aging face by restoring or creating fullness. However, fat grafting does much more than simply add volume. Grafted fat can transform or repair the tissues into which it is placed. Historically, surgeons have hesitated to embrace the rejuvenating potential of fat grafting because of poor graft take, fat necrosis, and inconsistent outcomes. This article describes fat grafting techniques and practices to assist readers in successful harvesting, processing, and placement of fat for optimal graft retention and facial esthetic outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Design of a Sapling Branch Grafting Robot

    Directory of Open Access Journals (Sweden)

    Qun Sun

    2014-01-01

    Full Text Available The automatic sapling grafting methods and grafting robot technologies are not comprehensively studied despite the fact that they are urgently required in practice. For this reason, a sapling grafting robot is developed to implement automatic grafting for saplings. The developed grafting robot includes clipping mechanism, moving mechanism, cutting mechanism, binding mechanism, and Arduino MCU based control system, which is capable of clipping, moving, positioning, cutting, grafting, and binding saplings. Experiments show that the stock cutting efficiency is 98.4%, the scion cutting efficiency is 98.9%, the grafting efficiency is 87.3%, and the binding efficiency is 68.9%.

  11. Nitrogen fixation in denitrified marine waters.

    Directory of Open Access Journals (Sweden)

    Camila Fernandez

    Full Text Available Nitrogen fixation is an essential process that biologically transforms atmospheric dinitrogen gas to ammonia, therefore compensating for nitrogen losses occurring via denitrification and anammox. Currently, inputs and losses of nitrogen to the ocean resulting from these processes are thought to be spatially separated: nitrogen fixation takes place primarily in open ocean environments (mainly through diazotrophic cyanobacteria, whereas nitrogen losses occur in oxygen-depleted intermediate waters and sediments (mostly via denitrifying and anammox bacteria. Here we report on rates of nitrogen fixation obtained during two oceanographic cruises in 2005 and 2007 in the eastern tropical South Pacific (ETSP, a region characterized by the presence of coastal upwelling and a major permanent oxygen minimum zone (OMZ. Our results show significant rates of nitrogen fixation in the water column; however, integrated rates from the surface down to 120 m varied by ∼30 fold between cruises (7.5±4.6 versus 190±82.3 µmol m(-2 d(-1. Moreover, rates were measured down to 400 m depth in 2007, indicating that the contribution to the integrated rates of the subsurface oxygen-deficient layer was ∼5 times higher (574±294 µmol m(-2 d(-1 than the oxic euphotic layer (48±68 µmol m(-2 d(-1. Concurrent molecular measurements detected the dinitrogenase reductase gene nifH in surface and subsurface waters. Phylogenetic analysis of the nifH sequences showed the presence of a diverse diazotrophic community at the time of the highest measured nitrogen fixation rates. Our results thus demonstrate the occurrence of nitrogen fixation in nutrient-rich coastal upwelling systems and, importantly, within the underlying OMZ. They also suggest that nitrogen fixation is a widespread process that can sporadically provide a supplementary source of fixed nitrogen in these regions.

  12. Nitrogen Fixation in Denitrified Marine Waters

    Science.gov (United States)

    Fernandez, Camila; Farías, Laura; Ulloa, Osvaldo

    2011-01-01

    Nitrogen fixation is an essential process that biologically transforms atmospheric dinitrogen gas to ammonia, therefore compensating for nitrogen losses occurring via denitrification and anammox. Currently, inputs and losses of nitrogen to the ocean resulting from these processes are thought to be spatially separated: nitrogen fixation takes place primarily in open ocean environments (mainly through diazotrophic cyanobacteria), whereas nitrogen losses occur in oxygen-depleted intermediate waters and sediments (mostly via denitrifying and anammox bacteria). Here we report on rates of nitrogen fixation obtained during two oceanographic cruises in 2005 and 2007 in the eastern tropical South Pacific (ETSP), a region characterized by the presence of coastal upwelling and a major permanent oxygen minimum zone (OMZ). Our results show significant rates of nitrogen fixation in the water column; however, integrated rates from the surface down to 120 m varied by ∼30 fold between cruises (7.5±4.6 versus 190±82.3 µmol m−2 d−1). Moreover, rates were measured down to 400 m depth in 2007, indicating that the contribution to the integrated rates of the subsurface oxygen-deficient layer was ∼5 times higher (574±294 µmol m−2 d−1) than the oxic euphotic layer (48±68 µmol m−2 d−1). Concurrent molecular measurements detected the dinitrogenase reductase gene nifH in surface and subsurface waters. Phylogenetic analysis of the nifH sequences showed the presence of a diverse diazotrophic community at the time of the highest measured nitrogen fixation rates. Our results thus demonstrate the occurrence of nitrogen fixation in nutrient-rich coastal upwelling systems and, importantly, within the underlying OMZ. They also suggest that nitrogen fixation is a widespread process that can sporadically provide a supplementary source of fixed nitrogen in these regions. PMID:21687726

  13. Hydrophilic/hydrophobic character of grafted cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, E., E-mail: takacs@iki.kfki.h [Institute of Isotopes, Hungarian Academy of Sciences, Budapest (Hungary); Wojnarovits, L. [Institute of Isotopes, Hungarian Academy of Sciences, Budapest (Hungary); Borsa, J. [Budapest University of Technology and Economics (Hungary); Racz, I. [Bay Zoltan Institute for Materials Science and Technology, Budapest (Hungary)

    2010-04-15

    Vinyl monomers with long paraffin chains were grafted onto two kinds of cellulose (cotton and cotton linter) by direct irradiation grafting technique. The effect of dose, monomer structure and concentration, as well as homopolymer suppressor (styrene) concentration on the grafting yield was studied and the optimal grafting conditions were established. Grafting decreased the swelling of the samples in water and increased their polymer compatibility in polypropylene matrix.

  14. Suprarenal fixation barbs can induce renal artery occlusion in endovascular aortic aneurysm repair.

    Science.gov (United States)

    Subedi, Shree K; Lee, Andy M; Landis, Gregg S

    2010-01-01

    Renal artery occlusion following endovascular abdominal aortic aneurysm repair with suprarenal fixation is uncommon. We report one patient who was found to develop renal artery occlusion and parenchymal infarction 6 months after repair using an endovascular graft with suprarenal fixation. Our patient underwent emergent endovascular repair of a symptomatic 6 cm abdominal aortic aneurysm. The covered portion of the endograft was inadvertently deployed well below the renal artery orifices. At the completion of the procedure both renal arteries were confirmed to be patent. One month postoperatively, a computed tomographic (CT) scan showed exclusion of the aortic sac and normal enhancement of both kidneys. At 6 months, the patient was found to have elevated serum creatinine levels despite having no clinical symptoms. CT scanning revealed a nonenhancing left kidney, and angiography demonstrated an occlusion of the left renal artery. A barb welded to the bare metal stent appeared to be impinging on the renal artery. We believe that renal artery occlusion after endovascular repair can occur due to repetitive injury to the renal artery orifice from barbs welded to the bare metal stent. To our knowledge, this is the first reported case of renal artery occlusion caused by repetitive injury from transrenal fixation systems. Copyright 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2015-05-01

    Conventional ligament grafts with single material composition cannot effectively integrate with the host bones due to mismatched properties and eventually affect their long-term function in vivo. Here we presented a multi-material strategy to design and fabricate composite scaffolds including ligament, interface and bone multiphased regions. The interface region consists of triphasic layers with varying material composition and porous structure to mimic native ligament-to-bone interface while the bone region contains polycaprolactone (PCL) anchor and microchanneled ceramic scaffolds to potentially provide combined mechanical and biological implant-bone fixation. Finite element analysis (FEA) demonstrated that the multiphased scaffolds with interference value smaller than 0.5 mm could avoid the fracture of ceramic scaffold during the implantation process, which was validated by in-vitro implanting the multiphased scaffolds into porcine joint bones. Pull-out experiment showed that the initial fixation between the multiphased scaffolds with 0.47 mm interference and the host bones could withstand the maximum force of 360.31±97.51 N, which can be improved by reinforcing the ceramic scaffolds with biopolymers. It is envisioned that the multiphased scaffold could potentially induce the regeneration of a new bone as well as interfacial tissue with the gradual degradation of the scaffold and subsequently realize long-term biological fixation of the implant with the host bone. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Surgical treatment for pilon fracture of the ankle-open reduction and internal fixation.

    Science.gov (United States)

    Chen, Y W; Huang, P J; Hsu, C Y; Kuo, C H; Cheng, Y M; Lin, S Y; Chen, L H; Chiang, H C

    1998-01-01

    From 1991 to 1994, 39 ankles of 38 patients underwent surgical open reduction and internal fixation for pilon fractures. These patients included 29 males and 9 females with an average age of 38.6 y/o (range 28 y/o-58 y/o). The follow up and evaluation period averaged 31.7 months (range 22Ms-44Ms), during which time a standing x-ray for arthrosis grading and functional scale was used for clinical evaluation. Complications included 1 case of infection, 1 case of loss reduction, 2 cases of partial skin necrosis and 2 cases of delayed union. Post-traumatic arthritis occurred in 23 ankles (59%) but only 4 ankles of grade 4 arthrosis resulted in poor functional scale and the overall satisfactory rate was 82%. It was found that anatomic reduction, rigid fixation and early motion exercise are important to successful treatment of ankle fractures. Regarding pilon fracture, specifically the severity of fracture pattern and delay of reduction are important problems to overcome to ensure successful results. Therefore, adequate surgical approach for entire view of ankle joint, reduction and fixation of fibula, sufficient bone graft for articular support, intraoperative x-ray check and postoperative immobilization are essential for the achievement of better clinical results.

  17. 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 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.

  18. Locking plate fixation in distal metaphyseal tibial fractures: series of 79 patients.

    Science.gov (United States)

    Gupta, Rakesh K; Rohilla, Rajesh Kumar; Sangwan, Kapil; Singh, Vijendra; Walia, Saurav

    2010-12-01

    Open reduction and internal fixation in distal tibial fractures jeopardises fracture fragment vascularity and often results in soft tissue complications. Minimally invasive osteosynthesis, if possible, offers the best possible option as it permits adequate fixation in a biological manner. Seventy-nine consecutive adult patients with distal tibial fractures, including one patient with a bilateral fracture of the distal tibia, treated with locking plates, were retrospectively reviewed. The 4.5-mm limited-contact locking compression plate (LC-LCP) was used in 33 fractures, the metaphyseal LCP in 27 fractures and the distal medial tibial LCP in the remaining 20 fractures. Fibula fixation was performed in the majority of comminuted fractures (n = 41) to maintain the second column of the ankle so as to achieve indirect reduction and to prevent collapse of the fracture. There were two cases of delayed wound breakdown in fractures fixed with the 4.5-mm LC-LCP. Five patients required primary bone grafting and three patients required secondary bone grafting. All cases of delayed union (n = 7) and nonunion (n = 3) were observed in cases where plates were used in bridge mode. Minimally invasive plate osteosynthesis (MIPO) with LCP was observed to be a reliable method of stabilisation for these fractures. Peri-operative docking of fracture ends may be a good option in severely impacted fractures with gap. The precontoured distal medial tibial LCP was observed to be a better tolerated implant in comparison to the 4.5-mm LC-LCP or metaphyseal LCP with respect to complications of soft tissues, bone healing and functional outcome, though its contour needs to be modified.

  19. Behaviour at landfills of waste having undergone mechanic-biological and thermal conditioning; Deponieverhalten mechanisch-biologisch und thermisch behandelten Restabfalls

    Energy Technology Data Exchange (ETDEWEB)

    Danhamer, H.; Dach, J.; Jager, J. [Institut WAR, Darmstadt (Germany). FG Abfalltechnik

    1998-12-31

    The work studies, in landfill test reactors, water, gas and heat transport as well as gas and leachate formation in waste having undergone mechanical-biological and thermal conditioning. (orig.) [Deutsch] Es wurde der Wasser-, Gas- und Waermetransport, sowie die Gasbildung- und Sickerwasserbelastung mechanisch-biologisch und thermisch vorbehandelter Abfaelle in Deponieversuchsreaktoren untersucht. (orig.)

  20. 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

  1. External fixation of “intertrochanteric” fractures

    Science.gov (United States)

    Gani, Naseem ul; Kangoo, Khursheed Ahmed; Bashir, Arshad; Muzaffer, Rahil; Bhat, Mohammad Farooq; Farooq, Munir; Badoo, Abdul Rashid; Dar, Imtiyaz Hussian; Wani, Mudassir Maqbool

    2009-01-01

    In developing countries, due to limited availability of modern anesthesia and overcrowding of the hospitals with patients who need surgery, high-risk patients with “intertrochanteric” fractures remain unsuita ble for open reduction and internal fixation. The aim of this study was to analyze the results of external fixation of “intertrochanteric” fractures in high-risk geriatric patients in a developing country. The results of 62 ambulatory high-risk geriatric patients with a mean age of 70 years (range 58–90 years) with “intertrochanteric” fractures, in whom external fixation was performed, are reported. Eight patients died during follow-up due to medical causes unrelated to the surgical procedure. So only 54 patients were available for final assessment. Procedure is simple, performed under local anesthesia, requires less time for surgery and is associated with less blood loss. Good fixation and early ambulation was achieved in most of the patients. Average time to union was 14 weeks. Thirty-one patients developed superficial pin tract infection and 28 patients had average shortening of 15 mm due to impaction and varus angulation. Functional outcome was assessed using Judet's point system. Good to excellent results were achieved in 44 patients. This study demonstrated that external fixation of “intertrochantric” fractures performed under local anesthesia offers significant advantage in ambulatory high-risk geriatric patients especially in a developing country. PMID:21808680

  2. External fixation of “intertrochanteric” fractures

    Directory of Open Access Journals (Sweden)

    Naseem ul Gani

    2009-08-01

    Full Text Available In developing countries, due to limited availability of modern anesthesia and overcrowding of the hospitals with patients who need surgery, high-risk patients with “intertro-chanteric” fractures remain unsuitable for open reduction and internal fixation. The aim of this study was to analyze the results of external fixation of “intertro-chanteric” fractures in high-risk geriatric patients in a developing country. The results of 62 ambulatory high-risk geriatric patients with a mean age of 70 years (range 58-90 years with “intertrochanteric” fractures, in whom external fixation was performed, are reported. Eight patients died during follow-up due to medical causes unrelated to the surgical procedure. So only 54 patients were available for final assessment. Procedure is simple, performed under local anesthesia, requires less time for surgery and is associated with less blood loss. Good fixation and early ambulation was achieved in most of the patients. Average time to union was 14 weeks. Thirty-one patients developed superficial pin tract infection and 28 patients had average shortening of 15 mm due to impaction and varus angulation. Functional outcome was assessed using Judet’s point system. Good to excellent results were achieved in 44 patients. This study demonstrated that external fixation of “intertrochantric” fractures performed under local anesthesia offers significant advantage in ambulatory high-risk geriatric patients especially in a developing country.

  3. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  4. FAS grafted superhydrophobic ceramic membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lu Jun [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Yu Yun, E-mail: yunyush@mail.sic.ac.cn [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Zhou Jianer [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Song Lixin; Hu Xingfang [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Larbot, Andre [Institut Europeen des Membranes, UMR 5635-CNRS, ENSCM, UMII, 1919 Route de Mende 34293, Montpellier Cedex 5 (France)

    2009-08-30

    The hydrophobic properties of {gamma}-Al{sub 2}O{sub 3} membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 deg. C) of the fluoroalkylsilane grafted on Al{sub 2}O{sub 3} powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and {gamma}-Al{sub 2}O{sub 3} membrane surface as well as the formed surface morphology.

  5. FAS grafted superhydrophobic ceramic membrane

    Science.gov (United States)

    Lu, Jun; Yu, Yun; Zhou, Jianer; Song, Lixin; Hu, Xingfang; Larbot, Andre

    2009-08-01

    The hydrophobic properties of γ-Al 2O 3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 °C) of the fluoroalkylsilane grafted on Al 2O 3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al 2O 3 membrane surface as well as the formed surface morphology.

  6. Interventions in Infrainguinal Bypass Grafts

    International Nuclear Information System (INIS)

    Mueller-Huelsbeck, S.; Order, B.-M.; Jahnke, T.

    2006-01-01

    The interventional radiologist plays an important role in the detection and prevention of infrainguinal bypass failure. Early detection and evaluation of flow-limiting lesions effectively preserve graft (venous bypass and polyester or expanded polytetrafluoroethylene bypass) patency by identifying stenoses before occlusion occurs. Delay in treatment of the at-risk graft may result in graft failure and a reduced chance of successful revascularization. For this reason, surveillance protocols form an important part of follow-up after infrainguinal bypass surgery. As well as having an understanding of the application of imaging techniques including ultrasound, MR angiography, CT angiography and digital subtraction angiography, the interventional radiologist should have detailed knowledge of the minimally invasive therapeutic options. Percutaneous transluminal angioplasty (PTA), or alternatively cutting balloon angioplasty, is the interventional treatment of choice in prevention of graft failure and occlusion. Further alternatives include metallic stent placement, fibrinolysis, and mechanical thrombectomy. Primary assisted patency rates following PTA can be up to 65% at 5 years. When the endovascular approach is unsuccessful, these therapeutic options are complemented by surgical procedures including vein patch revision, jump grafting, or placement of a new graft

  7. Defect nonunion of a metatarsal bone fracture in a cow: successful management with bone plating and autogenous cancellous bone graft.

    Science.gov (United States)

    Raghunath, M; Singh, N; Singh, T; Gopinathan, A; Mohindroo, J; Atri, K

    2013-01-01

    A two-and-half-year-old cow was presented with a defect nonunion of the right metatarsal III/IV bone following a severely comminuted open fracture two months previously. The animal underwent open fixation using a 4.5 mm, broad, 10-hole, dynamic compression plate and autogenous cancellous bone graft collected from the contralateral iliac shaft. The animal started partial weight bearing after the third postoperative day and resumed complete weight bearing after the 10th day. Fracture healing was complete and the implants were removed after the 120th postoperative day. Stable fixation by means of a bone plate in conjunction with a cancellous bone graft facilitated complete healing and restoration of the bone column of the defect and the metatarsal fracture. The animal made a complete recovery.

  8. Loads applied to fixations for chain stretching

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, K; Brychta, P

    1985-06-01

    The chains of scraper chain conveyors must be pre-stretched during standstill in order to compensate the elongations occurring during operation. They require frequent retensiening in order to meet the varying operational requirements. During tensioning, the chains are fixed in a point in the top run by means of fixation elements. The authors present a method for calculating the retaining force needed in the fixations. There are three different initial conditions of the chain before trensioning: Tensionsfree chain, pretensioned chain (stressed chain), slack chain. In all three cases, it is important to find out whether or nor the tensioning drive reaches full speed. The method of calculation is illustrated by the example of a scraper chain conveyor; it enables the establishment of rules for tensioning without damaging the chain and is a good basis for the dimensioning of new types of fixation elements.

  9. Biometric recognition via fixation density maps

    Science.gov (United States)

    Rigas, Ioannis; Komogortsev, Oleg V.

    2014-05-01

    This work introduces and evaluates a novel eye movement-driven biometric approach that employs eye fixation density maps for person identification. The proposed feature offers a dynamic representation of the biometric identity, storing rich information regarding the behavioral and physical eye movement characteristics of the individuals. The innate ability of fixation density maps to capture the spatial layout of the eye movements in conjunction with their probabilistic nature makes them a particularly suitable option as an eye movement biometrical trait in cases when free-viewing stimuli is presented. In order to demonstrate the effectiveness of the proposed approach, the method is evaluated on three different datasets containing a wide gamut of stimuli types, such as static images, video and text segments. The obtained results indicate a minimum EER (Equal Error Rate) of 18.3 %, revealing the perspectives on the utilization of fixation density maps as an enhancing biometrical cue during identification scenarios in dynamic visual environments.

  10. Radiation grafting on natural films

    International Nuclear Information System (INIS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37–40 N mm −1 ) and puncture deformation (PD=6.5–9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282–296 N mm −1 and PD of 5.0–5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films. - Highlights: • Irradiation of zein

  11. [Treatment of postoperative nonunion of fracture of lower limb with bone grafting by intervertebral disc endoscope].

    Science.gov (United States)

    Zhang, Jianlin; Tan, Yu'e; Ye, Jun; Han, Fangmin

    2012-02-01

    To explore the effectiveness of bone grafting by intervertebral disc endoscope for postoperative nonunion of fracture of lower limb. Between August 2004 and August 2008, 40 patients (23 males and 17 females) with postoperative nonunion of femoral and tibial fracture, aged 20-63 years (mean, 41.5 years) were treated. Nonunion of fracture occurred at 10-16 months after internal fixation. During the first operation, the internal fixation included interlocking intramedullary nailing of femoral fracture in 12 cases and plate in 16 cases, and interlocking intramedullary nailing of tibial fractures in 9 cases and plate in 3 cases. The X-ray films showed hypertrophic nonunion in 24 cases, common nonunion in 3 cases, and atrophic nonunion in 13 cases. The average operation time was 61 minutes (range, 40-80 minutes), and the blood loss was 80-130 mL (mean, 100 mL). The hospitalization time were 6-11 days (mean, 8.1 days). Incisions healed by first intention in all patients with no complication of infection or neurovascular injury. Forty patients were followed up 10-16 months (mean, 12.3 months). The X-ray films showed that all patients achieved healing of fracture after 4-10 months (mean, 6.8 months). No pain, disfunction, or internal fixation failure occurred. Bone grafting by intervertebral disc endoscope is an effective method for treating postoperative nonunion of femoral and tibial fracture.

  12. Tricortical cervical inter-body screw fixation.

    Directory of Open Access Journals (Sweden)

    Goel A

    1997-01-01

    Full Text Available A new tricortical method of screw implantation for anterior cervical interbody plate fixation is described. The screws are placed obliquely such that they engage the anterior cortex of the body and traverse through the cortices adjoining the disc space. By this method the screws not only hold the plate firmly with a tricortical purchase, but by virtue of their course stabilize the two adjoining vertebral bodies by themselves. Sixteen patients were treated by this method. In three of these cases only tricortical screws without the metal plate were used for fixation. The advantages of the technique are discussed.

  13. Cosmetic arm lengthening with monorail fixator.

    Science.gov (United States)

    Agrawal, Hemendra Kumar; Singh, Balvinder; Garg, Mohit; Khatkar, Vipin; Batra, Sumit; Sharma, Vinod Kumar

    2015-01-01

    Upper limb length discrepancy is a rare occurrence. Humerus shortening may need specialized treatment to restore the functional and cosmetic status of upper limb. We report a case of humerus lengthening of 9 cm with a monorail external fixator and the result was observed during a 2-year follow-up. Humerus lengthening needs specialized focus as it is not only a cosmetic issue but also a functional demand. The monorail unilateral fixator is more functional and cosmetically acceptable, and thus becomes an effective treatment option.

  14. Transient improvements in fixational stability in strabismic amblyopes following bifoveal fixation and reduced interocular suppression.

    Science.gov (United States)

    Raveendran, Rajkumar Nallour; Babu, Raiju J; Hess, Robert F; Bobier, William R

    2014-03-01

    To test the hypothesis that fixational stability of the amblyopic eye in strabismics will improve when viewing provides both bifoveal fixation and reduced inter-ocular suppression by reducing the contrast to the fellow eye. Seven strabismic amblyopes (Age: 29.2 ± 9 years; five esotropes and two exotropes) showing clinical characteristics of central suppression were recruited. Interocular suppression was measured by a global motion task. For each participant, a balance point was determined which defined contrast levels for each eye where binocular combination was optimal (interocular suppression minimal). When the balance point could not be determined, this participant was excluded. Bifoveal fixation was established by ocular alignment using a haploscope. Participants dichoptically viewed similar targets (a cross of 2.3° surrounded by a square of 11.3°) at 40 cm. Target contrasts presented to each eye were either high contrast (100% to both eyes) or balanced contrast (attenuated contrast in the fellow fixing eye). Fixation stability was measured over a 5 min period and quantified using bivariate contour ellipse areas in four different binocular conditions; unaligned/high contrast, unaligned/balance point, aligned/high contrast and aligned/balance point. Fixation stability was also measured in six control subjects (Age: 25.3 ± 4 years). Bifoveal fixation in the strabismics was transient (58.15 ± 15.7 s). Accordingly, fixational stability was analysed over the first 30 s using repeated measures anova. Post hoc analysis revealed that for the amblyopic subjects, the fixational stability of the amblyopic eye was significantly improved in aligned/high contrast (p = 0.01) and aligned/balance point (p suppression. However, once initiated, bifoveal fixation is transient with the strabismic eye drifting away from foveal alignment, thereby increasing the angle of strabismus. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

  15. Evolution of skin grafting for treatment of burns: Reverdin pinch grafting to Tanner mesh grafting and beyond.

    Science.gov (United States)

    Singh, Mansher; Nuutila, Kristo; Collins, K C; Huang, Anne

    2017-09-01

    Skin grafting is the current standard care in the treatment of full thickness burns. It was first described around 1500 BC but the vast majority of advancements have been achieved over the past 200 years. An extensive literature review was conducted on Pubmed, Medline and Google Scholar researching the evolution of skin grafting techniques. The authors concentrated on the major landmarks of skin grafting and also provide an overview of ongoing research efforts in this field. The major innovations of skin grafting include Reverdin pinch grafting, Ollier grafting, Thiersch grafting, Wolfe grafting, Padgett dermatome and modifications, Meek-wall microdermatome and Tanner mesh grafting. A brief description of the usage, advantages and limitations of each technique is included in the manuscript. Skin grafting technique have evolved significantly over past 200 years from Reverdin pinch grafting to modern day meshed skin grafts using powered dermatome. Increasing the expansion ratio and improving the cosmetic and functional outcome are the main focus of ongoing skin grafting research and emerging techniques (such as Integra ® , Recell ® , Xpansion ® ) are showing promise. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  16. Custom-made raster method for fistula and graft.

    Science.gov (United States)

    Blokker, C

    2005-01-01

    Unfamiliarity with fistula and graft characteristics can lead to failed punctures, haematomas and sometimes access occlusion. The Custom-made Raster Method provides detailed shunt visualisation and angiographic images by using photo-editing software. Access veins of an individual shunt and an adapted raster are projected on a digital picture of the arm. During angiography the shunt arm is fixated and a digital picture is taken from a fixed vertical angle and distance. Reference points are marked on the shunt arm, which serves as a fixation to draw a raster with coordination points. In this way a picture is created similar to a roadmap with veins. There is complete integration of digital and radiological images by using software programmes Adobe Photoshop + Illustrator or Agfa Web 1000 under Windows XP. All illustrations fit 1:1 by scaling up or down without distortion. Editing with Photoshop gives a precise projection of shunt veins on the real coloured background of the digital photograph. In this projection the grey angiography background is made completely transparent. The system can contain more detailed information in combination with echo (duplex) images of depth and diameter. This visualisation method is a useful tool for multi disciplinary access meetings with intervention radiologists, access surgeons and nephrologists. Access malfunction, aneurysms and stenosis can be projected at the exact location. The system leads to clear and concrete puncture advice. Transfer of access information and communication to other dialysis centres is facilitated.

  17. Unilateral fixation for treatment of occipitocervical instability in children with congenital vertebral anomalies of the craniocervical junction.

    Science.gov (United States)

    Mazur, Marcus D; Ravindra, Vijay M; Brockmeyer, Douglas L

    2015-04-01

    OBJECT Patients with occipitocervical (OC) instability from congenital vertebral anomalies (CVAs) of the craniocervical junction (CCJ) often have bony abnormalities that make instrumentation placement difficult. Within this patient population, some bilateral instrumentation constructs either fail or are not feasible, and a unilateral construct must be used. The authors describe the surgical management and outcomes of this disorder in patients in whom unilateral fixation constructs were used to treat OC instability. METHODS From a database of OC fusion procedures, the authors identified patients who underwent unilateral fixation for the management of OC instability. Patient characteristics, surgical details, and radiographic outcomes were reviewed. In each patient, CT scans were performed at least 4 months after surgery to evaluate for fusion. RESULTS Eight patients with CVAs of the CCJ underwent unilateral fixation for the treatment of OC instability. For 4 patients, the procedure occurred after a bilateral OC construct failed or infection forced hardware removal. For the remainder, it was the primary procedure. Two patients required reoperation for hardware revision and 1 developed nonunion requiring revision of the bone graft. Ultimately, 7 patients demonstrated osseous fusion on CT scans and 1 had a stable fibrous union. CONCLUSIONS These findings demonstrate that a unilateral OC fixation is effective for the treatment of OC instability in children with CVAs of the CCJ in whom bilateral screw placement fails or is not feasible.

  18. Energy production from mechanical biological treatment and Composting plants exploiting solid anaerobic digestion batch: An Italian case study

    International Nuclear Information System (INIS)

    Di Maria, F.; Sordi, A.; Micale, C.

    2012-01-01

    Highlights: ► This work quantifies the Italian Composting and MBT facilities upgradable by SADB. ► The bioCH 4 from SADB of source and mechanical selected OFMSW is of 220–360 Nl/kg VS. ► The upgrading investment cost is 30% higher for Composting than for MBT. ► Electricity costs are 0.11–0.28 €/kW h, not influenced by differentiate collection. ► Electrical energy costs are constant for SADB treating more than 30 ktons/year. - Abstract: The energetic potential of the organic fraction of municipal solid waste processed in both existing Composting plants and Mechanical Biological Treatment (MBT) plants, can be successfully exploited by retrofitting these plants with the solid anaerobic digestion batch process. On the basis of the analysis performed in this study, about 50 MBT plants and 35 Composting plants were found to be suitable for retrofitting with Solid Anaerobic Digestion Batch (SADB) facilities. Currently the organic fraction of Municipal Solid Waste (OFMSW) arising from the MBT facilities is about 1,100,000 tons/year, whereas that arising from differentiated collection and treated in Composting plants is about 850,000 tons/year. The SADB performances were analyzed by the aid of an experimental apparatus and the main results, in agreement with literature data, show that the biogas yield ranged from 400 to 650 Nl/kg of Volatile Solids (VS), with a methane content ranging from 55% to 60% v/v. This can lead to the production of about 500 GW h of renewable energy per year, giving a CO 2 reduction of about 270,000 tons/year. From the economic point of view, the analysis shows that the mean cost of a kW h of electrical energy produced by upgrading MBT and Composting facilities with the SADB, ranges from 0.11 and 0.28 €/kW h, depending on the plant size and the amount of waste treated.

  19. Fixation Characteristics of Severe Amblyopia Subtypes: Which One is Worse?

    Science.gov (United States)

    Koylu, Mehmet Talay; Ozge, Gokhan; Kucukevcilioglu, Murat; Mutlu, Fatih Mehmet; Ceylan, Osman Melih; Akıncıoglu, Dorukcan; Ayyıldız, Onder

    2017-01-01

    To determine differences in macular sensitivity and fixation patterns in different subtypes of severe amblyopia. This case-control study enrolled a total of 73 male adults, including 18 with pure strabismic severe amblyopia, 19 with pure anisometropic severe amblyopia, 18 with mixed (strabismic plus anizometropic) severe amblyopia, and 18 healthy controls. MP-1 microperimetry was used to evaluate macular sensitivity, location of fixation, and stability of fixation. Mean macular sensitivity, stability of fixation, and location of fixation were significantly worse in all amblyopia subtypes when compared with healthy controls. Intergroup comparisons between amblyopia subtypes revealed that mean macular sensitivity, stability of fixation, and location of fixation were significantly worse in pure strabismic and mixed amblyopic eyes when compared with pure anisometropic amblyopic eyes. Strabismus seems to be a worse prognostic factor in severe amblyopia than anisometropia in terms of fixation characteristics and retinal sensitivity.

  20. Sacroiliac screw fixation for tile B fractures.

    NARCIS (Netherlands)

    Bosch, E.W. van den; Zwienen, C.M. van; Hoek van Dijke, G.A.; Snijders, C.J.; Vugt, A.B. van

    2003-01-01

    BACKGROUND: The purpose of this comparative cadaveric study was to investigate whether the stability of partially unstable pelvic fractures can be improved by combining plate fixation of the symphysis with a posterior sacroiliac screw. METHODS: In six specimens, a Tile B1 (open-book) pelvic fracture

  1. Heterotrophic fixation of CO2 in soil

    Czech Academy of Sciences Publication Activity Database

    Šantrůčková, Hana; Bird, M. I.; Elhottová, Dana; Novák, Jaroslav; Picek, T.; Šimek, Miloslav; Tykva, Richard

    2005-01-01

    Roč. 49, č. 2 (2005), s. 218-225 ISSN 0095-3628 R&D Projects: GA ČR(CZ) GA206/02/1036; GA AV ČR(CZ) IAA6066901 Institutional research plan: CEZ:AV0Z60660521 Keywords : heterotrophic fixation * CO2 * soil Subject RIV: EH - Ecology, Behaviour Impact factor: 2.674, year: 2005

  2. Biodegradable interlocking nails for fracture fixation

    NARCIS (Netherlands)

    van der Elst, M.; Bramer, J. A.; Klein, C. P.; de Lange, E. S.; Patka, P.; Haarman, H. J.

    1998-01-01

    Serious problems such as stress shielding, allergic reactions, and corrosion are associated with the use of metallic fracture fixation devices in fractured long bones. Metal implants often are removed during a second retrieval operation after fracture healing has completed. A biocompatible implant

  3. Headspace analysis of foams and fixatives

    Energy Technology Data Exchange (ETDEWEB)

    Harper, Kyle [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Truong, Thanh-Tam [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Magwood, Leroy [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peters, Brent [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nicholson, James [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-27

    In the process of decontaminating and decommissioning (D&D) older nuclear facilities, special precautions must be taken with removable or airborne contamination. One possible strategy utilizes foams and fixatives to affix these loose contaminants. Many foams and fixatives are already commercially available, either generically or sold specifically for D&D. However, due to a lack of revelant testing in a radioactive environment, additional verification is needed to confirm that these products not only affix contamination to their surfaces, but also will function in a D&D environment. Several significant safety factors, including flammability and worker safety, can be analyzed through the process of headspace analysis, a technique that analyzes the off gas formed before or during the curing process of the foam/fixative, usually using gas chromatography-mass spectrometry (GC-MS). This process focuses on the volatile components of a chemical, which move freely between the solid/liquid form within the sample and the gaseous form in the area above the sample (the headspace). Between possibly hot conditions in a D&D situation and heat created in a foaming reaction, the volatility of many chemicals can change, and thus different gasses can be released at different times throughout the reaction. This project focused on analysis of volatile chemicals involved in the process of using foams and fixatives to identify any potential hazardous or flammable compounds.

  4. Miniplate fixation of Le Fort I osteotomies.

    Science.gov (United States)

    Rosen, H M

    1986-12-01

    The use of rigid, internal, three-dimensional fixation using vitallium bone plates in 28 consecutive Le Fort I osteotomies is presented. A minimum follow-up period of 6 months was required for inclusion in this patient group. Maxillary movements included advancements (17), intrusions (9), lengthenings (5), and retrusions (2). The majority of maxillae were moved in more than one plane of space. Technical details, complications, and relapse potential are discussed. Advantages of rigid plate fixation include marked reductions in the length of intermaxillary fixation with light training elastics only. Immediate postoperative airway problems are thereby eliminated. Six months of follow-up would appear to indicate a low potential for osseous relapse when compared to wire osteosynthesis, regardless of the direction of maxillary movement. The major disadvantage is the decreased ability of postoperative orthodontics to move dento-osseous segments if skeletal occlusal disharmony persists postoperatively. For this reason, close attention to preoperative planning and operative technique is critical for the success of this fixation method.

  5. Large fluctuations and fixation in evolutionary games

    International Nuclear Information System (INIS)

    Assaf, Michael; Mobilia, Mauro

    2010-01-01

    We study large fluctuations in evolutionary games belonging to the coordination and anti-coordination classes. The dynamics of these games, modeling cooperation dilemmas, is characterized by a coexistence fixed point separating two absorbing states. We are particularly interested in the problem of fixation that refers to the possibility that a few mutants take over the entire population. Here, the fixation phenomenon is induced by large fluctuations and is investigated by a semiclassical WKB (Wentzel–Kramers–Brillouin) theory generalized to treat stochastic systems possessing multiple absorbing states. Importantly, this method allows us to analyze the combined influence of selection and random fluctuations on the evolutionary dynamics beyond the weak selection limit often considered in previous works. We accurately compute, including pre-exponential factors, the probability distribution function in the long-lived coexistence state and the mean fixation time necessary for a few mutants to take over the entire population in anti-coordination games, and also the fixation probability in the coordination class. Our analytical results compare excellently with extensive numerical simulations. Furthermore, we demonstrate that our treatment is superior to the Fokker–Planck approximation when the selection intensity is finite

  6. 15N in biological nitrogen fixation studies

    International Nuclear Information System (INIS)

    Faust, H.

    1986-05-01

    A bibliography with 298 references on the use of the stable nitrogen isotope 15 N in the research on the biological fixation of dinitrogen is presented. The literature pertaining to this bibliography covers the period from 1975 to the middle of 1985. (author)

  7. The effect of fixation on esterases

    DEFF Research Database (Denmark)

    Kirkeby, S; Moe, D

    1984-01-01

    The localization of reaction product for non-specific esterase from fresh and aldehyde treated glandular tissue was examined. The electrophoretical studies showed a selective inhibition of certain isoenzymes and a change in mobility of some bands caused by aldehyde fixation. In sections a granular...

  8. Osteomyelitis in burn patients requiring skeletal fixation

    NARCIS (Netherlands)

    Barret, JP; Desai, MH; Herndon, DN

    Deep and severe burns often present with the exposure of musculoskeletal structures and severe deformities. Skeletal fixation, suspension and/or traction are part of their comprehensive treatment. Several factors put burn patients at risk for osteomyelitis, osteosynthesis material being one of them.

  9. 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.

  10. Plasma catalysis for nitrogen fixation reactions

    NARCIS (Netherlands)

    Patil, B.S.; Wang, Q.; Hessel, V.; Lang, J.; Stankiewicz, A.; Stefanidis, G.

    2016-01-01

    The preferences for localized chemicals production and changing scenarios of renewable electricity cost gives a renewed boost to plasma-assisted valuable chemicals production. Especially, plasma-assisted nitrogen fixation for fertilizer production has the potential to largely change the energy

  11. Comparative study of fixation density maps

    NARCIS (Netherlands)

    Engelke, U.; Liu, H.; Wang, Junle; Callet, Le P.; Heynderickx, I.E.J.; Zepernick, H.-J.; Maeder, A.

    2013-01-01

    Fixation density maps (FDM) created from eye tracking experiments are widely used in image processing applications. The FDM are assumed to be reliable ground truths of human visual attention and as such, one expects a high similarity between FDM created in different laboratories. So far, no studies

  12. Translaminar screw fixation in the lumbar spine: technique, indications, results

    OpenAIRE

    Grob, D.; Humke, T.

    1998-01-01

    Translaminar screw fixation of the lumbar spine represents a simple and effective technique for short segment fusion in the degenerative spine. Clinical experience with 173 patients who underwent translaminar screw fixation revealed a fusion rate of 94%. The indications for translaminar screw fixation as a primary fixation procedure are: segmental dysfunction, lumbar spinal stenosis with painful degenerative changes, segmental revision surgery after discectomies, and painful disc-related synd...

  13. Vascularized osseous graft for scaphoid

    International Nuclear Information System (INIS)

    Mendez Daza, Carlos Hernan; Mathoulin, Cristophe

    2004-01-01

    The most commonly used technique for treatment of pseudo-arthrosis of the scaphoid is osteo-synthesis with Kirschnet wires and cortical sponge grafts. Results reported by different teams using this procedure show no more than 90% osseous consolidation, especially in cases where vascularisation of the proximal fragment of the scaphoid is compromised. Here we present a series of ten cases of pseudo-arthrosis of the scaphoid, treated using a new surgical technique involving a vascularized osseous graft of the distal radius. Using this procedure we obtained 100% consolidation, with no complications either during the procedure or immediately post-operatively. Patients returned to work in week 15 on average. In 4 cases we observed discomfort in the area of the scar, which was successfully treated using local cortisone injection. The results obtained are very similar to those seen in the literature on the different techniques for vascularized osseous grafts for pseudo-arthrosis of the scaphoid

  14. Characterization for Soil Fixation by Polyelectrolyte Complex

    International Nuclear Information System (INIS)

    Choi, Yong Suk; Kwon, Sang Woon; Yang, Heeman; Lee, Kune Woo; Seo, Bumkyoung; Moon, Jei Kwon

    2014-01-01

    According to report, the radioactivity bulk (approx. 95%) is localized within topsoil. Therefore soil surface on topsoil should be fixed to prevent the spreading of the contaminated soils with Cs-137 by wind and water erosion. Many methods have been developing for soil fixation to remove radioactive contaminants in soil and prevent to diffuse radioactive materials. Various materials have been also used as fixatives such as clays, molecular sieves, polymer, and petroleum based products. One of the methods is a soil fixation or solidification using polyelectrolyte. Polyelectrolytes have many ionic groups and make into the polyelectrolyte complex (PEC) due to electrostatic interaction of polyanion and polycation in an aqueous solution. It can be avoids using the chemical cross-linking agents, and reducing the possible toxicity and other undesirable effects of the reagents. PEC can fix soil particles by flocculation and formation of crust between soil. The method can also prevent a spread of radioactive material by floating on a soil surface. Recently, PEC used for the solidification of soil near the Fukushima nuclear power plant in Japan. The decontamination efficiency of the surface soils reached 90%, and dust release was effectively suppressed during the removal of surface soils. In this study, it was investigated the fixation of the soil by PEC to avoid the spread of the contamination in addition to the separation of soil and PEC. The physicochemical properties of polyelectrolyte complex solution and the stability of fixed soil by PEC were investigated. The mode of the addition is important to prepare the polyelectrolytes complex without PAA agglomerate. The concentration of salt in the polyelectrolyte complex solution is a very important parameter for the soil fixation

  15. Characterization for Soil Fixation by Polyelectrolyte Complex

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Suk; Kwon, Sang Woon; Yang, Heeman; Lee, Kune Woo; Seo, Bumkyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    According to report, the radioactivity bulk (approx. 95%) is localized within topsoil. Therefore soil surface on topsoil should be fixed to prevent the spreading of the contaminated soils with Cs-137 by wind and water erosion. Many methods have been developing for soil fixation to remove radioactive contaminants in soil and prevent to diffuse radioactive materials. Various materials have been also used as fixatives such as clays, molecular sieves, polymer, and petroleum based products. One of the methods is a soil fixation or solidification using polyelectrolyte. Polyelectrolytes have many ionic groups and make into the polyelectrolyte complex (PEC) due to electrostatic interaction of polyanion and polycation in an aqueous solution. It can be avoids using the chemical cross-linking agents, and reducing the possible toxicity and other undesirable effects of the reagents. PEC can fix soil particles by flocculation and formation of crust between soil. The method can also prevent a spread of radioactive material by floating on a soil surface. Recently, PEC used for the solidification of soil near the Fukushima nuclear power plant in Japan. The decontamination efficiency of the surface soils reached 90%, and dust release was effectively suppressed during the removal of surface soils. In this study, it was investigated the fixation of the soil by PEC to avoid the spread of the contamination in addition to the separation of soil and PEC. The physicochemical properties of polyelectrolyte complex solution and the stability of fixed soil by PEC were investigated. The mode of the addition is important to prepare the polyelectrolytes complex without PAA agglomerate. The concentration of salt in the polyelectrolyte complex solution is a very important parameter for the soil fixation.

  16. External fixation combined with delayed internal fixation in treatment of tibial plateau fractures with dislocation.

    Science.gov (United States)

    Tao, Xingguang; Chen, Nong; Pan, Fugen; Cheng, Biao

    2017-10-01

    The aim of this study was to evaluate the clinical efficacy of external fixation, delayed open reduction, and internal fixation in treating tibial plateau fracture with dislocation.Clinical data of 34 patients diagnosed with tibial plateau fracture complicated with dislocation between January 2009 and May 2015 were retrospectively analyzed. Fifteen patients in group A underwent early calcaneus traction combined with open reduction and internal fixation and 19 in group B received early external fixation combined with delayed open reduction and internal fixation. Operation time, postoperative complication, bone healing time, knee joint range of motion, initial weight-bearing time, Rasmussen tibial plateau score, and knee function score (HSS) were statistically compared between 2 groups.The mean follow-up time was 18.6 months (range: 5-24 months). The mean operation time in group A was 96 minutes, significantly longer than 71 minutes in group B (P  .05). In group A, initial weight-bearing time in group A was (14.0 ± 3.6) weeks, significantly differing from (12.9 ± 2.8) weeks in group B (P  0.05). Rasmussen tibial plateau score in group A was slightly lower than that in group B (P > .05). The excellent rate of knee joint function in group A was 80% and 84.21% in group B (P > .05).External fixation combined with delayed open reduction and internal fixation is a safer and more efficacious therapy of tibial plateau fracture complicated with dislocation compared with early calcaneus traction and open reduction and internal fixation.

  17. [Treatment of pediatric distal femur fractures by external fixator combined with limited internal fixation].

    Science.gov (United States)

    Wei, Sheng-wang; Shi, Zhan-ying; Hu, Ju-zheng; Wu, Hao

    2016-03-01

    To discuss the clinical effects of external fixator combined with limited internal fixation in the treatment of pediatric distal femur fractures. From January 2008 to June 2014, 17 children of distal femur fractures were treated by external fixator combined with limited internal fixation. There were 12 males and 5 females, aged from 6 to 13 years old with an average of 10.2 years, ranged in the course of disease from 1 h to 2 d. Preoperative diagnoses were confirmed by X-ray films in all children. There were 11 patients with supracondylar fracture , and 6 patients with intercondylar comminuted fracture. According to AO/ASIF classification, 9 fractures were type A1, 5 cases were type A2,and 3 cases were type C1. The intraoperative and postoperative complications, postoperative radiological examination, lower limbs length and motion of knee joints were observed. Knee joint function was assessed by KSS score. All the patients were followed up from 6 to 38 months with an average of 24.4 months. No nerve or blood vessel injury was found. One case complicated with the external fixation loosening, 2 cases with the infection of pin hole and 3 cases with the leg length discrepancy. Knee joint mobility and length measurement (compared with the contralateral), the average limited inflexion was 10 degrees (0 degrees to 20 degrees), the average limited straight was 4 degrees (0 degrees to 10), the average varus or valgus angle was 3 degrees (0 degrees to 5 degrees). KSS of the injured side was (96.4 +/- 5.0) points at final follow-up, 16 cases got excellent results and 1 good. All fractures obtained healing and no epiphyseal closed early was found. External fixator combined with limited internal fixation has advantages of simple operation, reliable fixation, early functional exercise in treating pediatric distal femurs fractures.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  19. Comparison of skeletal stability after sagittal split ramus osteotomy among mono-cortical plate fixation, bi-cortical plate fixation, and hybrid fixation using absorbable plates and screws.

    Science.gov (United States)

    Ueki, Koichiro; Moroi, Akinori; Yoshizawa, Kunio; Hotta, Asami; Tsutsui, Takamitsu; Fukaya, Kenichi; Hiraide, Ryota; Takayama, Akihiro; Tsunoda, Tatsuta; Saito, Yuki

    2017-02-01

    The purpose of this study was to examine skeletal stability and plate breakage after sagittal split ramus osteotomy (SSRO) with the mono-cortical plate fixation, bi-cortical plate fixation, and hybrid fixation techniques using absorbable plates and screws. A total of 76 Japanese patients diagnosed with mandibular prognathism with and without maxillary deformity were divided into 3 groups randomly. A total of 28 patients underwent SSRO with mono-cortical plate fixation, 23 underwent SSRO with bi-cortical plate fixation, and 25 underwent SSRO with hybrid fixation. Skeletal stability and horizontal condylar angle were analyzed by axial, frontal, and lateral cephalograms from before the operation to 1 year postoperatively. Breakage of the plate and screws was observed by 3-dimensional computed tomography (3DCT) immediately after surgery and after 1 year. Although there was a significant difference between the mono-cortical plate fixation group and hybrid fixation group regarding right MeAg in T1 (P = 0.0488) and occlusal plane in T1 (P = 0.0346), there were no significant differences between the groups for the other measurements in each time interval. In 2 cases, namely, 6 sides in the mono-cortical plate fixation group, breakage of the absorbable plate was found by 3DCT. However, there was no breakage in the bi-cortical plate fixation group and hybrid fixation group. This study results suggested that there were no significant differences in the postoperative skeletal stability among the 3 groups, and bi-cortical fixation as well as hybrid fixation was a reliable and useful method to prevent plate breakage even if an absorbable material was used. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  20. Grafted SiC nanocrystals

    DEFF Research Database (Denmark)

    Saini, Isha; Sharma, Annu; Dhiman, Rajnish

    2017-01-01

    ), raman spectroscopy and X-ray diffraction (XRD) measurements. UV–Visible absorption spectroscopy was used to study optical properties such as optical energy gap (Eg), Urbach's energy (Eu), refractive index (n), real (ε1) and imaginary (ε2) parts of dielectric constant of PVA as well as PVA......Polyvinyl alcohol (PVA) grafted SiC (PVA-g-SiC)/PVA nanocomposite was synthesized by incorporating PVA grafted silicon carbide (SiC) nanocrystals inside PVA matrix. In-depth structural characterization of resulting nanocomposite was carried out using fourier transform infrared spectroscopy (FTIR...

  1. Mechanical-biological waste treatment with thermal processing of partial fractions; Mechanisch-biologische Restabfallbehandlung unter Einbindung thermischer Verfahren fuer Teilfraktionen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Technologies for mechanical-biological treatment of waste in the Land of Hessen were compared including thermal processes like combustion and gasification. The new and more rigid limiting values specified in the Technical Guide for Municipal Waste Treatment (Technische Anleitung Siedlungsabfall - TASI) get a special mention. [Deutsch] Verschiedene Technologien der mechanisch-biologischen Restabfallbehandlung im Raum Hessen wurden unter Einbezug thermischer Verfahren (Verbrennung, Vergasung) miteinander verglichen. Dabei wurden besonders auf die verschaerften Grenzwerte der Technischen Anleitung Siedlungsabfall (TASI) eingegangen. (ABI)

  2. Oral mucosa grafts for urethral reconstruction

    African Journals Online (AJOL)

    reports reveal that split and full thickness skin grafts from the scrotum, penis, extragenital sites (ureter, saphenous .... Table 1: Summary of the history of oral mucosa grafts for urethroplasty .... advised that care should be taken when suturing the.

  3. Postoperative radiographic evaluation of vascularized fibular grafts

    International Nuclear Information System (INIS)

    Manaster, B.J.; Coleman, D.A.; Bell, D.A.

    1989-01-01

    This paper reports on thirty-five patients with free vascularized fibular grafts examined postoperatively with plain radiography. Early graft incorporation is seen as a fuzziness of the cortex at the site of its insertion into the host bone. Causes of failure in grafting for bone defects include graft fracture, hardware failure, and infection. A high percentage of complications or at least delayed unions occurred when vascularized fibular grafts were used to fill defects in the lower extremity. Conversely, upper extremity defects bridged by vascularized grafts heal quickly and hypertrophy. Vascularized grafts placed in the femoral head and neck for a vascular necrosis incorporate early on their superior aspect. The osseous tunnel in which they are placed is normally wider than the graft and often becomes sclerotic; this appearance does not represent nonunion

  4. [Effect of iliolumbar fixation in patients with Tile C pelvic injury and analysis of relative factors].

    Science.gov (United States)

    Ge, Zhenxin; Wang, Ben; Zhang, Dongzheng; Liu, Zhaojie; Zhang, Yinguang; Jia, Jian

    2012-11-01

    To explore the relative prognostic factors of Tile C pelvic injury after iliolumbar fixation. Between March 2007 and March 2010, 60 patients with Tile C pelvic injuries were surgically treated with iliolumbar fixation, including 39 males and 21 females with an average age of 37 years (range, 17-66 years). Of them, 27 cases were classified as Tile C1, 20 as Tile C2, and 13 as Tile C3. The preoperative injury severity score (ISS) was 12-66 (mean, 29.4). The time from injury to surgery was 2-25 days (mean, 8.1 days). Iliolumbar fixation was performed in all patients. Unconditional logistic analysis was used to analyze the relationship between the age, sex, body mass index (BMI), operation opportunity, the preoperative combined injury, classification of fracture, the postoperative complication, reduction outcome, sacral nerve injury, and the time of physical exercise and the prognosis. All 60 patients were followed up 12-56 months (mean, 27.3 months). Infection of incisions occurred in 12 cases and were cured after dressing change; healing of incision by first intention was obtained in the other patients. Delay sacral nerve injury was found in 15 patients, 6 patients underwent nerve decompression, and 9 underwent conservative treatment. Ten patients had nail protrusion of Schanz screws at the posterior superior illac spine, and 3 patients had pain, which was relieved after removal of the internal fixator. One patient had bone-grafting nonunion of sacroiliac joint, which was improved by pressured bone graft. Five patients had the beam breakage without significant effect. Six patients had deep vein thrombosis, among them 4 underwent filter and 2 underwent nonsurgical treatment. The healing time of fracture was 3-6 months (mean, 3.9 months). According to the Matta function score, the results were excellent in 31 cases, good in 24 cases, fair in 3 cases, and poor in 2 cases with an excellent and good rate of 91.7% at last follow-up. Majeed score was 58-100 (mean, 86), 28

  5. Prevention of primary vascular graft infection with silver-coated polyester graft in a porcine model

    DEFF Research Database (Denmark)

    Gao, H; Sandermann, J; Prag, J

    2010-01-01

    To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model.......To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model....

  6. Evaluation of Replacement Grafts and Punch Grafts in the Treatment of Vitiligo

    Directory of Open Access Journals (Sweden)

    Singh Ajit Kumar

    1980-01-01

    Full Text Available Thirtycasesof vitiligo eachwithminimum of two lesions undent replacement graft and multiple punch grafts in one lesion each. Complications observed at the recipient site like infection and raised nigosed surface were significantly more in replacement grafts. Hypopigmentation of the graft was significantly more when the disease was progressive.

  7. The in vitro viability and growth of fibroblasts cultured in the presence of different bone grafting materials (NanoBone and Straumann Bone Ceramic).

    Science.gov (United States)

    Kauschke, E; Rumpel, E; Fanghänel, J; Bayerlein, T; Gedrange, T; Proff, P

    2006-02-01

    Different clinical applications, including dentistry, are making increasing demands on bone grafting material. In the present study we have analysed the viability, proliferation and growth characteristics of fibroblasts cultured in vitro together with two different bone grafting materials, NanoBone and Straumann Bone Ceramic, over a period of 24 and 28 days respectively. Viability was measured at least every 72 hours by using the alamarBlue assay, a test that measures quantitatively cell proliferation and viability but does not require cell fixation or extraction. After one week of culture fibroblast viability was as high as in controls for both grafting materials and remained high (> 90%) for the duration of the experiment. Cell growth was evaluated microscopically. Scanning electron microscopy revealed a dense fibroblast growth at the surface of both bone grafting materials after three weeks of in vitro culture. Generally, our in vitro analyses contribute to further insights into cell - scaffold interactions.

  8. Graft infections after surgical aortic reconstructions

    NARCIS (Netherlands)

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open

  9. Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

    Science.gov (United States)

    Ward, Christopher; Ciraulo, David; Coulter, Michael; Desjardins, Steven; Liaw, Lucy; Peterson, Sarah

    2012-08-01

    Negative-pressure wound therapy (NPWT) has been used for to treat wounds for more than 15 years and, more recently, has been used to secure split-thickness skin grafts. There are some data to support this use of NPWT, but the actual mechanism by which NPWT speeds healing or improves skin graft take is not entirely known. The purpose of this project was to assess whether NPWT improved angiogenesis, wound healing, or graft survival when compared with traditional bolster dressings securing split-thickness skin grafts in a porcine model. We performed two split-thickness skin grafts on each of eight 30 kg Yorkshire pigs. We took graft biopsies on postoperative days 2, 4, 6, 8, and 10 and submitted the samples for immunohistochemical staining, as well as standard hematoxylin and eosin staining. We measured the degree of vascular ingrowth via immunohistochemical staining for von Willenbrand's factor to better identify blood vessel epithelium. We determined the mean cross-sectional area of blood vessels present for each representative specimen, and then compared the bolster and NPWT samples. We also assessed each graft for incorporation and survival at postoperative day 10. Our analysis of the data revealed that there was no statistically significant difference in the degree of vascular ingrowth as measured by mean cross-sectional capillary area (p = 0.23). We did not note any difference in graft survival or apparent incorporation on a macroscopic level, although standard hematoxylin and eosin staining indicated that microscopically, there seemed to be better subjective graft incorporation in the NPWT samples and a nonsignificant trend toward improved graft survival in the NPWT group. We were unable to demonstrate a significant difference in vessel ingrowth when comparing NPWT and traditional bolster methods for split-thickness skin graft fixation. More studies are needed to elucidate the manner by which NPWT exerts its effects and the true clinical magnitude of these

  10. Reoperative surgical stabilization of a painful nonunited rib fracture using bone grafting and a metal plate.

    Science.gov (United States)

    Cho, Yang Hyun; Kim, Hyun Koo; Kang, Du-Young; Choi, Young Ho

    2009-09-01

    We report a case of a nonunited sixth rib in a patient with multiple rib fractures who underwent internal fixation using a wire and Judet strut 3 times. During the following 3 years, the patient continued to complain of pain and instability. At surgery, a pseudarthrosis between the ends of the sixth rib was excised. A longitudinal gutter crossing the fracture site was fashioned and splinted with an inlay block of cancellous bone grafted from the iliac crest; stabilization was accomplished with a reconstruction plate and screws. The following 2 years of follow-up demonstrated no instability or pain.

  11. The caudal septum replacement graft.

    Science.gov (United States)

    Foda, Hossam M T

    2008-01-01

    To describe a technique for reconstructing the lost tip support in cases involving caudal septal and premaxillary deficiencies. The study included 120 patients with aesthetic and functional nasal problems resulting from the loss of caudal septal and premaxillary support. An external rhinoplasty approach was performed to reconstruct the lost support using a cartilaginous caudal septum replacement graft and premaxillary augmentation with Mersilene mesh. The majority of cases (75%) involved revisions in patients who had previously undergone 1 or more nasal surgical procedures. A caudal septum replacement graft was combined with premaxillary augmentation in 93 patients (77.5%). The mean follow-up period was 3 years (range, 1-12 years). The technique succeeded in correcting the external nasal deformities in all patients and resulted in a significant improvement in breathing in 74 patients (86%) with preoperative nasal obstruction. There were no cases of infection, displacement, or extrusion. The caudal septum replacement graft proved to be very effective in restoring the lost tip support in patients with caudal septal deficiency. Combining the graft with premaxillary augmentation using Mersilene mesh helped increase support and stability over long-term follow-up.

  12. ACL Graft Healing and Biologics

    NARCIS (Netherlands)

    Muller, Bart; Bowman, Karl F.; Bedi, Asheesh

    2013-01-01

    Operative reconstruction of a torn anterior cruciate ligament (ACL) has become the most broadly accepted treatment. An important, but underreported, outcome of ACL reconstruction is graft failure, which poses a challenge for the orthopedic surgeon. An understanding of the tendon-bone healing and the

  13. Polyether-polyester graft copolymer

    Science.gov (United States)

    Bell, Vernon L. (Inventor)

    1987-01-01

    Described is a polyether graft polymer having improved solvent resistance and crystalline thermally reversible crosslinks. The copolymer is prepared by a novel process of anionic copolymerization. These polymers exhibit good solvent resistance and are well suited for aircraft parts. Previous aromatic polyethers, also known as polyphenylene oxides, have certain deficiencies which detract from their usefulness. These commercial polymers are often soluble in common solvents including the halocarbon and aromatic hydrocarbon types of paint thinners and removers. This limitation prevents the use of these polyethers in structural articles requiring frequent painting. In addition, the most popular commercially available polyether is a very high melting plastic. This makes it considerably more difficult to fabricate finished parts from this material. These problems are solved by providing an aromatic polyether graft copolymer with improved solvent resistance and crystalline thermally reversible crosslinks. The graft copolymer is formed by converting the carboxyl groups of a carboxylated polyphenylene oxide polymer to ionic carbonyl groups in a suitable solvent, reacting pivalolactone with the dissolved polymer, and adding acid to the solution to produce the graft copolymer.

  14. Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies

    International Nuclear Information System (INIS)

    Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M.; Pichlmaier, M.

    2001-01-01

    Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140±46 ml/min before, 137±58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [de

  15. Nitrogen fixation improvement in Faidherbia albida

    International Nuclear Information System (INIS)

    Toure, O.; Dasilva, M.C.; Badji, S.; Dianda, M.; Ndoye, I.; Gueye, M.

    1998-01-01

    A greenhouse experiment investigated growth, N accumulation and N 2 fixation (using the 15 N-dilution method) by Faidherbia albida in comparison with three species of Acacia, with Parkia biglobosa and Tamarindus indica as non-fixing reference plants. Faidherbia albida was mediocre in comparison with A. seyel, therefore seven provenances of the former were examined in a second pot experiment to investigate within-species variability for the same performance components; a provenance from Kabrousse, Senegal, showed particular promise in terms of dry weight and N accumulation, and fixation of N. This promise was confirmed with a 15-month field experiment, but revealed that there is opportunity for further improvement in N 2 -fixing ability. Faidherbia albida is a slow-growing tree, therefore further field experiments with provenance Kabrousse should be longer term in scope. The data indicate that trenching of the 15 N-labelled area may not be necessary. (author)

  16. Intrasacral rod fixation for pediatric lumbopelvic fusion.

    Science.gov (United States)

    Ilharreborde, Brice; Mazda, Keyvan

    2014-07-01

    This paper reports the authors' 19 years experience with pediatric intrasacral rod fixation. After insertion of two cannulated screws in S1 with and an original template guiding them into the anterior third of the endplate, two short fusion rods were inserted into the sacrum according to Jackson's technique distally to S3. In neuromuscular scoliosis, pelvic obliquity was reduced by connecting the proximal and distal constructs, distraction or compression, and in situ rod bending. In children with high-grade spondylolisthesis, lumbosacral kyphosis was reduced by rotation of the sacrum and in situ bending. There were no direct neurological or vascular injuries. The main complication was infection (7%). No pseudarthrosis or significant loss of correction at the lumbosacral junction was observed during follow-up. Intrasacral rod fixation appears to be safe and reliable for lumbopelvic fusion in pediatric patients.

  17. The Bolton Treovance abdominal stent-graft: European clinical trial design.

    Science.gov (United States)

    Chiesa, R; Riambau, V; Coppi, G; Zipfel, B; Llagostera, S; Marone, E M; Kahlberg, A

    2012-10-01

    Endovascular aortic repair (EVAR) has emerged as a promising, less invasive alternative to conventional open surgery for the treatment of infrarenal abdominal aortic aneurysms (AAAs). In the last 20 years, the application rate of EVAR and its clinical results have significantly improved thanks to the evolution of stent-grafts and endovascular delivery systems. However, further development is still needed to reduce the incidence of complications and secondary re-interventions. The Treovance abdominal aortic stent-graft (Bolton Medical, Barcelona, Spain) is a new-generation endovascular device, developed to increase flexibility, lower profile, improve deployment and sealing mechanisms. In particular, it is provided with some innovative features as a double layer of proximal barbs (suprarenal and infrarenal) for supplemental fixation, dull barbs between modules to avoid potential leg disconnections, detachable outer sheath provided with a new-design hemostatic valve, and a double improved mechanism (slow motion and "pin and pull") for precise stent-graft deployment. A European prospective, non-randomized, multi-institutional, "first-in-human" trial (the ADVANCE trial) was conducted from March to December 2011 to assess the safety and performance of the Treovance stent-graft system before commercialization. Thirty patients with anatomically suitable non-ruptured AAAs were enrolled at five clinical sites in Italy, Spain, and Germany. EVAR was completed successfully in all patients. The stent-graft was delivered and deployed safely even in heavily angulated or calcified anatomies. No 30-day device-related complications nor deaths were observed. Preliminary experience with the Treovance abdominal stent-graft within the ADVANCE trial was satisfactory with regard to technical success and perioperative clinical results. Follow-up data are needed to assess mid- and long-term clinical outcomes, along with durability of this new-generation endovascular device.

  18. Homogeneous cation exchange membrane by radiation grafting

    International Nuclear Information System (INIS)

    Kolhe, Shailesh M.; G, Agathian; Ashok Kumar

    2001-01-01

    Preparation of a strong cation exchange membrane by radiation grafting of styrene on to polyethylene (LDPE) film by mutual irradiation technique in the presence of air followed by sulfonation is described. The grafting has been carried out in the presence of air and without any additive. Low dose rate has been seen to facilitate the grafting. Further higher the grafting percentage more is the exchange capacity. The addition of a swelling agent during the sulfonation helped in achieving the high exchange capacity. The TGA-MASS analysis confirmed the grafting and the sulfonation. (author)

  19. Scaphoid Fracture Fixation with an Acutrak? Screw

    OpenAIRE

    Loving, Vilert A.; Richardson, Michael L.

    2015-01-01

    We report a case of fixation of a scaphoid fracture using an Acutrak? screw. This screw is cannulated and headless, which allows it to be implanted below the surface of the bone. It uses the same concept of variable thread pitch as the Herbert screw, but unlike the Herbert screw, is fully threaded, with continuously varying pitch along its length. This variable pitch creates constant compression across a fracture as the screw is advanced, and gives the screw its unique appearance. This featur...

  20. High level waste fixation in cermet form

    International Nuclear Information System (INIS)

    Kobisk, E.H.; Aaron, W.S.; Quinby, T.C.; Ramey, D.W.

    1981-01-01

    Commercial and defense high level waste fixation in cermet form is being studied by personnel of the Isotopes Research Materials Laboratory, Solid State Division (ORNL). As a corollary to earlier research and development in forming high density ceramic and cermet rods, disks, and other shapes using separated isotopes, similar chemical and physical processing methods have been applied to synthetic and real waste fixation. Generally, experimental products resulting from this approach have shown physical and chemical characteristics which are deemed suitable for long-term storage, shipping, corrosive environments, high temperature environments, high waste loading, decay heat dissipation, and radiation damage. Although leach tests are not conclusive, what little comparative data are available show cermet to withstand hydrothermal conditions in water and brine solutions. The Soxhlet leach test, using radioactive cesium as a tracer, showed that leaching of cermet was about X100 less than that of 78 to 68 glass. Using essentially uncooled, untreated waste, cermet fixation was found to accommodate up to 75% waste loading and yet, because of its high thermal conductivity, a monolith of 0.6 m diameter and 3.3 m-length would have only a maximum centerline temperature of 29 K above the ambient value

  1. Nitrogen fixation in Red Sea seagrass meadows

    KAUST Repository

    Abdallah, Malak

    2017-05-01

    Seagrasses are key coastal ecosystems, providing many ecosystem services. Seagrasses increase biodiversity as they provide habitat for a large set of organisms. In addition, their structure provides hiding places to avoid predation. Seagrasses can grow in shallow marine coastal areas, but several factors regulate their growth and distribution. Seagrasses can uptake different kinds of organic and inorganic nutrients through their leaves and roots. Nitrogen and phosphorous are the most important nutrients for seagrass growth. Biological nitrogen fixation is the conversion of atmospheric nitrogen into ammonia by diazotrophic bacteria. This process provides a significant source of nitrogen for seagrass growth. The nitrogen fixation is controlled by the nif genes which are found in diazotrophs. The main goal of the project is to measure nitrogen fixation rates on seagrass sediments, in order to compare among various seagrass species from the Red Sea. Moreover, we will compare the fixing rates of the Vegetated areas with the bare sediments. This project will help to ascertain the role of nitrogen fixing bacteria in the development of seagrass meadows.

  2. [Complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures: a meta-analysis].

    Science.gov (United States)

    Yang, Z; Yuan, Z Z; Ma, J X; Ma, X L

    2016-12-20

    Objective: To make a systematic assessment of the complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Method: A computer-based online search of PubMed, ScienceDirect, EMBASE, BIOSIS, Springer and Cochrane Library were performed.The randomized and controlled trials of open reduction and internal fixation versus external fixation for unstable distal radius fractures were collected.The included trials were screened out strictly based on the criterion of inclusion and exclusion.The quality of included trials was evaluated.RevMan 5.0 was used for data analysis. Result: A total of 17 studies involving 1 402 patients were included.There were 687 patients with open reduction and internal fixation and 715 with external fixation.The results of Meta-analysis indicated that there were statistically significant differences with regard to the postoperatively total complications, infection, malunion, tendon rupture ( I 2 =8%, RR =0.77(95% CI 0.65-0.91, Z =3.10, P 0.05). Conclusion: Postoperative complications are present in both open reduction and internal fixation and external fixation.Compared with external fixation, open reduction and internal fixation is lower in total complications postoperatively, infection and malunion, but external fixation has lower tendon rupture incidence.

  3. Effectiveness of external fixator combined with T-plate internal fixation for the treatment of comminuted distal radius fractures.

    Science.gov (United States)

    Han, L R; Jin, C X; Yan, J; Han, S Z; He, X B; Yang, X F

    2015-03-31

    This study compared the efficacy between external fixator combined with palmar T-plate internal fixation and simple plate internal fixation for the treatment of comminuted distal radius fractures. A total of 61 patients classified as type C according to the AO/ASIF classification underwent surgery for comminuted distal radius fractures. There were 54 and 7 cases of closed and open fractures, respectively. Moreover, 19 patients received an external fixator combined with T-plate internal fixation, and 42 received simple plate internal fixation. All patients were treated successfully during 12-month postoperative follow-up. The follow-up results show that the palmar flexion and dorsiflexion of the wrist, radial height, and palmar angle were significantly better in those treated with the external fixator combined with T-plate compared to those treated with the simple plate only (P 0.05). Hence, the effectiveness of external fixator combined with T-plate internal fixation for the treatment of comminuted distal radius fractures was satisfactory. Patients sufficiently recovered wrist, forearm, and hand function. In conclusion, compared to the simple T-plate, the external fixator combined with T-plate internal fixation can reduce the possibility of the postoperative re-shifting of broken bones and keep the distraction of fractures to maintain radial height and prevent radial shortening.

  4. Comparison of screw fixation with elastic fixation methods in the treatment of syndesmosis injuries in ankle fractures.

    Science.gov (United States)

    Seyhan, Mustafa; Donmez, Ferdi; Mahirogullari, Mahir; Cakmak, Selami; Mutlu, Serhat; Guler, Olcay

    2015-07-01

    17 patients with ankle syndesmosic injury were treated with a 4.5mm single cortical screw fixation (passage of screw 4 cortices) and 15 patients were treated with single-level elastic fixation material. All patients were evaluated according to the AOFAS ankle and posterior foot scale at the third, sixth and twelfth months after the fixation. The ankle range of movement was recorded together with the healthy side. The Student's t test was used for statistical comparisons. No statistical significant difference was observed between the AOFAS scores (p>0.05). The range of dorsiflexion and plantar flexion motion of the elastic fixation group at the 6th and 12th months were significantly better compared to the screw fixation group (pankle syndesmosis injuries. The unnecessary need of a second surgical intervention for removal of the fixation material is another advantageous aspect of this method of fixation. Copyright © 2015. Published by Elsevier Ltd.

  5. [Extramedullary fixation combined with intramedullary fixation in the surgical reduction of sagittal mandibular condylar fractures].

    Science.gov (United States)

    Chuanjun, Chen; Xiaoyang, Chen; Jing, Chen

    2016-10-01

    This study aimed to evaluate the clinical effect of extramedullary fixation combined with intramedullary fixation during the surgical reduction of sagittal mandibular condylar fractures. Twenty-four sagittal fractures of the mandibular condyle in18 patients were fixed by two appliances: intramedullary with one long-screw osteosynthesis or Kirschner wire and extramedullary with one micro-plate. The radiologically-recorded post-operative stability-associated com-plications included the screw/micro-plate loosening, micro-plate twisting, micro-plate fractures, and fragment rotation. The occluding relations, the maximalinter-incisal distances upon mouth opening, and the mandibular deflection upon mouth opening were evaluated based on follow-up clinical examination. Postoperative panoramic X-ray and CT scans showed good repositioning of the fragment, with no redislocation or rotation, no screw/plate loosening, and no plate-twisting or fracture. Clinical examination showed that all patients regained normal mandibular movements, ideal occlusion, and normal maximal inter-incisal distances upon mouth opening. Extramedullary fixation combined with intramedullary fixation is highly recommended for sagittal condylar fractures because of the anti-rotation effect of the fragment and the reasonable place-ment of the fixation appliances.

  6. Studies on radiation-induced graft polymerization

    International Nuclear Information System (INIS)

    Omichi, Hideki

    1978-09-01

    Radiation-induced graft polymerization is used extensively to improve physical properties of polymers, but few processes are now commercialized. The reason for this is partly inadequate basic research on the reaction and partly the difficulty in developing the grafting process with large radiation source. Firstly, new techniques are proposed of studying kinetics of the graft polymerization in heterogeneous system. Based on the grafting yield, the molecular weight of graft chains, and the amount of radicals given by ESR and activation analysis, kinetic parameters are obtained and the reaction mechanism of grafting process is discussed. Secondly, the development of grafting process of poly (vinyl chloride)-butadiene is described. By study of the reaction, process design, construction and operation of the pilot plant, and economic analysis of the process, this process with 60 Co gamma ray sources is shown to be industrially promising. (author)

  7. Dynamics of bone graft healing around implants

    Directory of Open Access Journals (Sweden)

    Narayan Venkataraman

    2015-01-01

    A few questions arise pertaining to the use of bone grafts along with implants are whether these are successful in approximation with implant. Do they accelerate bone regeneration? Are all defects ultimately regenerated with new viable bone? Is the bone graft completely resorbed or integrated in new bone? Does the implant surface characteristic positively affect osseointegration when used with a bone graft? What type of graft and implant surface can be used that will have a positive effect on the healing type and time? Finally, what are the dynamics of bone graft healing around an implant? This review discusses the cellular and molecular mechanisms of bone graft healing in general and in vicinity of another foreign, avascular body, namely the implant surface, and further, the role of bone grafts in osseointegration and/or clinical success of the implants.

  8. Only fixation for cervical spondylosis: Report of early results with a preliminary experience with 6 cases

    Directory of Open Access Journals (Sweden)

    Atul Goel

    2013-01-01

    Full Text Available Aim: The author reports early post-operative outcome and preliminary experience with an alternative form of treatment of cervical degenerative or spondylotic disease leading to spinal canal stenosis that involves fixation-arthrodesis of the affected spinal segment using one or two (double insurance transarticular screws for each joint. Materials and Methods: During the period of months from March 2013 to July 2013, six patients having cervical spondylotic cord compression were treated with transarticular method of screw fixation of the involved segments. The operation involved section of the spinous process at its base, opening up of the facet joint, denuding of articular cartilage, placement of intraarticular cavity bone graft chips and insertion of either a single or two transarticular screws at each level. The fixation was done in four levels in four patients and at two levels in two patients. Japanese Orthopedic Association score, visual analog scale (neck pain and Odom′s criteria were used to monitor the clinical status of the patients before and after the surgery and at follow-up. Results: Immediate post-operative and a relatively short-term post-operative outcome was remarkably gratifying. During the average period of follow-up of 6 months (range: 3-8 months; there was varying degree of recovery of symptoms. The procedure resulted in firm stabilization and fixation of the spinal segment and provided a ground for arthrodesis. No patient worsened after treatment. During the period of follow-up, all patients showed remarkable and progressive recovery in symptoms. Conclusions: Vertical instability and telescoping, listhesis or overriding of the facets on physical activity seems to be the defining phenomenon in pathogenesis of cervical spondylotic disease. The clinical outcome in our patients suggest that only fixation of the spinal segment can be a rationale form of treatment. Transarticular method of treatment is a simple, safe and

  9. 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.

  10. Computed tomography evaluation of autogenous graft in sinus lift surgery; Analise por tomografia computadorizada do enxerto autogeno na cirurgia de 'sinus lift'

    Energy Technology Data Exchange (ETDEWEB)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Tecnica Operatoria e Cirurgia Experimental; Alves, Maria Teresa de Seixas [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Anatomia Patologica

    2001-02-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  11. Mechanical compliance and immunological compatibility of fixative-free decellularized/cryopreserved human pericardium.

    Directory of Open Access Journals (Sweden)

    Maria Cristina Vinci

    Full Text Available BACKGROUND: The pericardial tissue is commonly used to produce bio-prosthetic cardiac valves and patches in cardiac surgery. The procedures adopted to prepare this tissue consist in treatment with aldehydes, which do not prevent post-graft tissue calcification due to incomplete xeno-antigens removal. The adoption of fixative-free decellularization protocols has been therefore suggested to overcome this limitation. Although promising, the decellularized pericardium has not yet used in clinics, due to the absence of proofs indicating that the decellularization and cryopreservation procedures can effectively preserve the mechanical properties and the immunologic compatibility of the tissue. PRINCIPAL FINDINGS: The aim of the present work was to validate a procedure to prepare decellularized/cryopreserved human pericardium which may be implemented into cardiovascular homograft tissue Banks. The method employed to decellularize the tissue completely removed the cells without affecting ECM structure; furthermore, uniaxial tensile loading tests revealed an equivalent resistance of the decellularized tissue to strain, before and after the cryopreservation, in comparison with the fresh tissue. Finally, immunological compatibility, showed a minimized host immune cells invasion and low levels of systemic inflammation, as assessed by tissue transplantation into immune-competent mice. CONCLUSIONS: Our results indicate, for the first time, that fixative-free decellularized pericardium from cadaveric tissue donors can be banked according to Tissue Repository-approved procedures without compromising its mechanical properties and immunological tolerance. This tissue can be therefore treated as a safe homograft for cardiac surgery.

  12. [Effectiveness of posterior intrasegmental fixation with pedicle screw-lamina hook system in treatment of lumbar spondylolysis].

    Science.gov (United States)

    Zhou, Zhongjie; Song, Yueming; Zeng, Jiancheng; Liu, Hao; Liu, Limin; Kong, Qingquan; Li, Tao; Gong, Quan

    2013-03-01

    To investigate the effectiveness of posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting for lumbar spondylolysis. Between January 2005 and October 2009, 22 patients with lumbar spondylolysis underwent posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting. There were 19 males and 3 females with an average age of 18.4 years (range, 12-26 years). The main symptom was low back pain with an average disease duration of 16 months (range, 8-56 months). The visual analogue scale (VAS) was 6.0 +/- 1.2 and Oswestry disability index (ODI) was 72.0% +/- 10.0% preoperatively. The X-ray films showed bilateral spondylolysis at L4 in 9 cases and at L5 in 13 cases. The range of motion (ROM) at upper and lower intervertebral spaces was (11.8 +/- 2.8) degrees and (14.1 +/- 1.9) degrees, respectively. All incisions healed by first intention. All patients were followed up 12-45 months (mean, 25 months). Low back pain was significantly alleviated after operation. The VAS score (0.3 +/- 0.5) and ODI (17.6% +/- 3.4%) were significantly decreased at last follow-up when compared with preoperative scores (P spondylolysis, having a high fusion rate, low complication rate, and maximum retention of lumbar ROM.

  13. Results of application of external fixation with different types of fixators

    Directory of Open Access Journals (Sweden)

    Grubor Predrag

    2012-01-01

    Full Text Available Introduction. Extra-focal or external fixation is the method of fracture fixation through the healthy part of the bone using pins or wires. Objective. The aim was to determine which external splints (Ortofix, Mitković, Charnley and Ilizarov had the best biomechanical properties in primary stabilization of spiral, transverse and commutative bone fractures. Methods. To determine the investigation methodology of biomechanical characteristics of the external fixator we used mathematical and computer simulator (software, juvidur physical model and clinical examination. Results. Values of advancing fragments in millimetres obtained by the study of mathematical and computer simulator (software: Charnley - 0.080 mm, Mitković M 20 - 0.785 mm, Ilizarov - 2.245 mm and Ortofix - 1.400 mm. In testing the juvidur model the following values were obtained: the external fixator Mitković M20 - 1.380 mm, Ortofix - 1.470 mm, Ilizarov - 2.410 mm, and Charnley - 2.510 mm. Clinical research of biomechanical characteristics of the effect of vertical force yielded the following results: Mitković M20 - 0.89 mm, Ortofix - 0.14 mm, Charnley - 0.80 mm and Ilizarov - 1.23 mm. Conclusion. When determining the total number of the stability test splints under the effect of vertical force (compression and force effect in antero-posterior, later-lateral plane of cross, spiral and comminuted long bone fractures, the best unified biomechanical stability was shown by the following external fixators: firstly, Mitković M20 (0.93mm, secondly, Charnley fixator (1.14 mm, thirdly, Ortofix (1.22 mm, and fourthly, Ilizarov (1.60 mm.

  14. Septal graft in laryngeal reconstruction

    International Nuclear Information System (INIS)

    Bahannan, Abdulrahman; Slavicek, A.; Taudy, M.; Chovanec, M.

    2006-01-01

    A 62-year-old woman presented with symptoms of dyspnea. Ultrasonography and computed tomography examinations revealed mass extending from the cricoid cartilage to the left lobe of thyroid gland and thyroid cartilage. Cytology revealed possibility of cartilaginous origin, which was proven to be chondrosarcoma (Grade 1) from the biopsy specimen obtained during panendosopy. She underwent one stage radical resection and immediate reconstruction of laryngeal skeleton defect by mucocartilaginous graft from the nasal septum. Her postoperative course was optimal with preservation of the laryngeal functions. Twenty-eight months postoperatively, she had to undergo total laryngectomy as a salvage procedure for the advanced local recurrence. We report on the relatively easy technique for functional reconstruction of the large laryngeal defect with the employment cartilage graft from the nasal septum. (author)

  15. Determining the degree of grafting for poly (vinylidene fluoride) graft-copolymers using fluorine elemental analysis

    International Nuclear Information System (INIS)

    Yu Yang; Zhang Bowu; Yang Xuanxuan; Deng Bo; Li Linfan; Yu Ming; Li Jingye

    2011-01-01

    Acrylic acid (AAc) and styrene (St) were grafted onto poly (vinylidene fluoride) (PVDF) powder or membrane samples by pre-irradiation graft copolymerization. The grafted chains were proved by FT-IR spectroscopy analysis. The degree of grafting (DG) of the grafted PVDF was determined by fluorine elemental analysis (FEA) method, and was compared with the DGs determined by weighing method, acid-base back titration method and quantitative FT-IR method. The results show that the FEA method is accurate, convenient and universal, especially for the grafted polymer powders. (authors)

  16. Treatment of Spinal Tuberculosis by Debridement, Interbody Fusion and Internal Fixation via Posterior Approach Only.

    Science.gov (United States)

    Tang, Ming-xing; Zhang, Hong-qi; Wang, Yu-xiang; Guo, Chao-feng; Liu, Jin-yang

    2016-02-01

    Surgical treatment for spinal tuberculosis includes focal tuberculosis debridement, segmental stability reconstruction, neural decompression and kyphotic deformity correction. For the lesions mainly involved anterior and middle column of the spine, anterior operation of debridement and fusion with internal fixation has been becoming the most frequently used surgical technique for the spinal tuberculosis. However, high risk of structural damage might relate with anterior surgery, such as damage in lungs, heart, kidney, ureter and bowel, and the deformity correction is also limited. Due to the organs are in the front of spine, there are less complications in posterior approach. Spinal pedicle screw passes through the spinal three-column structure, which provides more powerful orthopedic forces compared with the vertebral body screw, and the kyphotic deformity correction effect is better in posterior approach. In this paper, we report a 68-year-old male patient with thoracic tuberculosis who underwent surgical treatment by debridement, interbody fusion and internal fixation via posterior approach only. The patient was placed in prone position under general anesthesia. Posterior midline incision was performed, and the posterior spinal construction was exposed. Then place pedicle screw, and fix one side rod temporarily. Make the side of more bone destruction and larger abscess as lesion debridement side. Resect the unilateral facet joint, and retain contralateral structure integrity. Protect the spinal cord, nerve root. Clear sequestrum, necrotic tissue, abscess of paravertebral and intervertebral space. Specially designed titanium mesh cages or bone blocks were implanted into interbody. Fix both side rods and compress both sides to make the mesh cages and bone blocks tight. Reconstruct posterior column structure with allogeneic bone and autologous bone. Using this technique, the procedures of debridement, spinal cord decompression, deformity correction, bone grafting

  17. The Improvement of Bone-Tendon Fixation by Porous Titanium Interference Screw: A Rabbit Animal Model.

    Science.gov (United States)

    Tsai, Pei-I; Chen, Chih-Yu; Huang, Shu-Wei; Yang, Kuo-Yi; Lin, Tzu-Hung; Chen, San-Yuan; Sun, Jui-Sheng

    2018-05-04

    The interference screw is a widely used fixation device in the anterior cruciate ligament (ACL) reconstruction surgeries. Despite the generally satisfactory results, problems of using interference screws were reported. By using additive manufacturing (AM) technology, we developed an innovative titanium alloy (Ti 6 Al 4 V) interference screw with rough surface and inter-connected porous structure designs to improve the bone-tendon fixation. An innovative Ti 6 Al 4 V interference screws were manufactured by AM technology. In vitro mechanical tests were performed to validate its mechanical properties. Twenty-seven New Zealand white rabbits were randomly divided into control and AM screw groups for biomechanical analyses and histological analysis at 4, 8 and 12 weeks postoperatively; while micro-CT analysis was performed at 12 weeks postoperatively. The biomechanical tests showed that the ultimate failure load in the AM interference screw group was significantly higher than that in the control group at all tested periods. These results were also compatible with the findings of micro-CT and histological analyses. In micro-CT analysis, the bone-screw gap was larger in the control group; while for the additive manufactured screw, the screw and bone growth was in close contact. In histological study, the bone-screw gaps were wider in the control group and were almost invisible in the AM screw group. The innovative AM interference screws with surface roughness and inter-connected porous architectures demonstrated better bone-tendon-implant integration, and resulted in stronger biomechanical characteristics when compared to traditional screws. These advantages can be transferred to future interference screw designs to improve their clinical performance. The AM interference screw could improve graft fixation and eventually result in better biomechanical performance of the bone-tendon-screw construct. The innovative AM interference screws can be transferred to future

  18. [Autologous fat grafting in children].

    Science.gov (United States)

    Baptista, C; Bertrand, B; Philandrianos, C; Degardin, N; Casanova, D

    2016-10-01

    Lipofilling or fat grafting transfer is defined as a technique of filling soft tissue by autologous fat grafting. The basic principle of lipofilling is based on a harvest of adipose tissue, followed by a reinjection after treatment. Lipofilling main objective is a volume defect filling, but also improving cutaneous trophicity. Lipofilling specificities among children is mainly based on these indications. Complications of autologous fat grafting among children are the same as those in adults: we distinguish short-term complications (intraoperative and perioperative) and the medium and long-term complications. The harvesting of fat tissue is the main limiting factor of the technique, due to low percentage of body fat of children. Indications of lipofilling among children may be specific or similar to those in adults. There are two types of indications: cosmetic, in which the aim of lipofilling is correcting a defect density, acquired (iatrogenic, post-traumatic scar) or malformation (otomandibular dysplasia, craniosynostosis, Parry Romberg syndrom, Poland syndrom, pectus excavatum…). The aim of functional indications is correcting a velar insufficiency or lagophthalmos. In the paediatric sector, lipofilling has become an alternative to the conventional techniques, by its reliability, safety, reproducibility, and good results. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Management and follow up of tibial plateau fractures by ′T′ clamp external fixator and limited internal fixation

    Directory of Open Access Journals (Sweden)

    Thimmegowda M

    2005-01-01

    Full Text Available Background: Tibial plateau fractures are difficult to treat especially when soft tissue is compromised by open reduction and internal fixation. Many methods have be1en tried in the past to manage these cases of which external fixation were shown to be effective as they limit the soft tissue and wound complications. Methods: Complex tibial plateau fractures of sixteen patients were treated by closed reduction, fixation of articular fragments by screws and application of unilateral external fixator. The external fixator was kept in place till fracture united clinically and radiologically. The patients were followed up for at least one year to assess the function of the knee joint Results: The average duration of external fixation was 13 weeks. All the fractures healed. Pin track infection (five patients and instability (six patients of the knee were encountered with this procedure. The average duration of follow up was 62 weeks. The mean range of motion was 1250 arc. The IOWA knee score averaged 90.3 points. Conclusions: External fixation with limited internal fixation may be effective in the management of complex tibial plateau fractures which requires further support from studies with large sample size. ′T′ clamp external fixation with limited Internal fixation is the procedure of choice when alignment, stability, early mobilisation is required in a soft tissue compromised tibial plateau fractures.

  20. Improving Saliency Models by Predicting Human Fixation Patches

    KAUST Repository

    Dubey, Rachit

    2015-04-16

    There is growing interest in studying the Human Visual System (HVS) to supplement and improve the performance of computer vision tasks. A major challenge for current visual saliency models is predicting saliency in cluttered scenes (i.e. high false positive rate). In this paper, we propose a fixation patch detector that predicts image patches that contain human fixations with high probability. Our proposed model detects sparse fixation patches with an accuracy of 84 % and eliminates non-fixation patches with an accuracy of 84 % demonstrating that low-level image features can indeed be used to short-list and identify human fixation patches. We then show how these detected fixation patches can be used as saliency priors for popular saliency models, thus, reducing false positives while maintaining true positives. Extensive experimental results show that our proposed approach allows state-of-the-art saliency methods to achieve better prediction performance on benchmark datasets.

  1. Improving Saliency Models by Predicting Human Fixation Patches

    KAUST Repository

    Dubey, Rachit; Dave, Akshat; Ghanem, Bernard

    2015-01-01

    There is growing interest in studying the Human Visual System (HVS) to supplement and improve the performance of computer vision tasks. A major challenge for current visual saliency models is predicting saliency in cluttered scenes (i.e. high false positive rate). In this paper, we propose a fixation patch detector that predicts image patches that contain human fixations with high probability. Our proposed model detects sparse fixation patches with an accuracy of 84 % and eliminates non-fixation patches with an accuracy of 84 % demonstrating that low-level image features can indeed be used to short-list and identify human fixation patches. We then show how these detected fixation patches can be used as saliency priors for popular saliency models, thus, reducing false positives while maintaining true positives. Extensive experimental results show that our proposed approach allows state-of-the-art saliency methods to achieve better prediction performance on benchmark datasets.

  2. Bilateral Laparoscopic Totally Extraperitoneal Repair Without Mesh Fixation

    OpenAIRE

    Dehal, Ahmed; Woodward, Brandon; Johna, Samir; Yamanishi, Frank

    2014-01-01

    Background and Objectives: Mesh fixation during laparoscopic totally extraperitoneal repair is thought to be necessary to prevent recurrence. However, mesh fixation may increase postoperative chronic pain. This study aimed to describe the experience of a single surgeon at our institution performing this operation. Methods: We performed a retrospective review of the medical records of all patients who underwent bilateral laparoscopic totally extraperitoneal repair without mesh fixation for ing...

  3. Application of monorail fixator for femoral gap nonunion

    Directory of Open Access Journals (Sweden)

    Agrawal Hemendra Kumar

    2014-07-01

    Full Text Available 【Abstract】Difficult femoral nonunion takes account of infective nonunion and aseptic gap nonunion. Limb length discrepancy and nonunion need to be tackled simultaneously. Conventionally Ilizarov ring fixator is in vogue but it has some limitations. To overcome these, monorail fixator is an effective alternative. Persistent good results can be obtained if we can get a perfect anatomical alignment and good regeneration. Key words: Femur; Ilizarov technique; External fixators

  4. Editor's Choice - Renal complications after EVAR with suprarenal versus infrarenal fixation among all users and routine users.

    Science.gov (United States)

    Zettervall, S L; Deery, S E; Soden, P A; Shean, K; Siracuse, J J; Alef, M; Patel, V I; Schermerhorn, M L

    2017-09-01

    Previous studies comparing endografts with suprarenal and infrarenal fixation for endovascular abdominal aortic aneurysm repair (EVAR) have found conflicting results and did not account for differences in patient selection. This study aims to evaluate the differences in outcomes among surgeons who routinely use either suprarenal or infrarenal fixation, as well as all surgeons in the Vascular Study Group of New England (VSGNE). All patients undergoing EVAR in the VSGNE from 2003 to 2014 were identified. All ruptured aneurysms, repairs with concomitant procedures, and infrequently used stent grafts (80% of cases, as well as all surgeons. Multivariate regression and Cox hazard models were utilised to account for patient demographics, comorbidities, operative differences, and procedure year. This study identified 2574 patients (suprarenal, 1264; infrarenal, 1310) with 888 endografts placed by routine users (suprarenal, 409; infrarenal, 479). There were no differences in baseline comorbidities, including the estimated glomerular filtration rate, between suprarenal and infrarenal fixation, or between patients with endografts placed by routine and non-routine users. Patients treated with suprarenal endografts received more contrast than all users (102 mL vs. 100 mL, p = .01) and routine users (110 mL vs. 88 mL, p users, patients treated with suprarenal grafts had higher rates of creatinine increase >.5 mg/dL (3.7% vs. 2.0%, p = .01), length of stay >2 days (27% vs. 19%, p users, suprarenal fixation was also associated with higher rates of renal dysfunction (3.7% vs. 1.3%, p = .02; OR 2.9; 95% CI 1.1-7.8). Despite potential differences in patient selection, endografts with suprarenal fixation among all users and routine users were associated with higher rates of renal deterioration and longer length of hospital stay. Longer-term data are needed to determine the duration and severity of renal function decline and to identify potential benefits of decreased

  5. Anterior debridement and fusion followed by posterior pedicle screw fixation in pyogenic spondylodiscitis: autologous iliac bone strut versus cage.

    Science.gov (United States)

    Pee, Yong Hun; Park, Jong Dae; Choi, Young-Geun; Lee, Sang-Ho

    2008-05-01

    An anterior approach for debridement and fusion with autologous bone graft has been recommended as the gold standard for surgical treatment of pyogenic spondylodiscitis. The use of anterior foreign body implants at the site of active infection is still a challenging procedure for spine surgeons. Several authors have recently introduced anterior grafting with titanium mesh cages instead of autologous bone strut in the treatment of spondylodiscitis. The authors present their experience of anterior fusion with 3 types of cages followed by posterior pedicle screw fixation. They also compare their results with the use of autologous iliac bone strut. The authors retrospectively reviewed the cases of 60 patients with pyogenic spondylodiscitis treated by anterior debridement between January 2003 and April 2005. Fusion using either cages or iliac bone struts was performed during the same course of anesthesia followed by posterior fixation. Twenty-three patients underwent fusion with autologous iliac bone strut, and 37 patients underwent fusion with 1 of the 3 types of cages. The infections resolved in all patients, as noted by normalization of their erythrocyte sedimentation rates and C-reactive protein levels. Patients in both groups were evaluated in terms of their preoperative and postoperative clinical and imaging findings. Single-stage anterior debridement and cage fusion followed by posterior pedicle screw fixation can be effective in the treatment of pyogenic spondylodiscitis. There was no difference in clinical and imaging outcomes between the strut group and cage group except for the subsidence rate. The subsidence rate was higher in the strut group than in the cage group. The duration until subsidence was also shorter in the strut group than in the cage group.

  6. Rib Fracture Fixation: Indications and Outcomes.

    Science.gov (United States)

    Senekjian, Lara; Nirula, Raminder

    2017-01-01

    Rib fractures are a frequently identified injury in the trauma population. Not only are multiple rib fractures painful, but they are associated with an increased risk of adverse outcomes. Pneumonia in particular can be devastating, especially to an elderly patient, but other complications such as prolonged ventilation and increased intensive care and hospital durations of stay have a negative impact on the patient. Computed tomography scan is the best modality to diagnosis rib fractures but the treatment of fractures is still evolving. Currently patient care involves a multidisciplinary approach that includes pain control, aggressive pulmonary therapy, and possibly surgical fixation. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Nitrogen fixation on a coral reef

    Energy Technology Data Exchange (ETDEWEB)

    Mague, T.H.; Holm-Hansen, O.

    1975-06-01

    Benthic, heterocystous blue-green algae (genera Calothrix, Hormothamnion and Nostoc) from Eniwetok Atoll were found to reduce acetylene at rapid rates. Slight acetylene reduction was associated with samples of Rhizoclonium (Chlorophyceae) and Oscillatoria (a cyanophyte lacking heterocysts), but this may have been due to contamination by epiphytes. There was virtually no acetylene reduction by phytoplankton, and nutrient enrichment experiments failed to selectively increase the numbers or activity of N/sub 2/-fixing algae in surface water samples. The Nostoc required light for acetylene reduction. Nitrogen fixation by this species could have supplied up to 11 ..mu..g N/cm/sup 2//day to the ecosystem. (auth)

  8. Distal fingertip replantation without skeletal fixation.

    Science.gov (United States)

    Sabapathy, S Raja; Venkatramani, Hari; Bharathi, R Ravindra; Sebastin, Sandeep J

    2005-01-01

    The replantation of fingertip amputation (through the nail bed) requires repair of the artery and vein on the palmar side. These structures are present in different planes, with the artery being deeper and the veins superficial. The authors believe that vascular repair in such cases is facilitated by stabilization of the amputated part by nail-bed repair alone. This provides a certain degree of flexibility, which allows for easier placement of clamps in the limited space available. Although Kirschner wires were not used for bony fixation, bony union was achieved in all five cases in which this technique was used.

  9. Bypass grafting to the anterior tibial artery.

    Science.gov (United States)

    Armour, R H

    1976-01-01

    Four patients with severe ischaemia of a leg due to atherosclerotic occlusion of the tibial and peroneal arteries had reversed long saphenous vein grafts to the patent lower part of the anterior tibial artery. Two of these grafts continue to function 19 and 24 months after operation respectively. One graft failed on the fifth postoperative day and another occluded 4 months after operation. The literature on femorotibial grafting has been reviewed. The early failure rate of distal grafting is higher than in the case of femoropopliteal bypass, but a number of otherwise doomed limbs can be salvaged. Contrary to widely held views, grafting to the anterior tibial artery appears to give results comparable to those obtained when the lower anastomosis is made to the posterior tibial artery.

  10. Overcoming design fixation through education and creativity methods

    DEFF Research Database (Denmark)

    Howard, Thomas J.; Maier, Anja; Onarheim, Balder

    2013-01-01

    . The first intervention consisted of educating each team on the phenomena and effects of design fixation. The results showed that this intervention reduced the number of fixation elements in comparison to the control group (p=0.025). The second intervention involved using Dix et als' (2006) 'Bad Ideas...... of ideas produced per group and the groups' fixation ratios, adding to the quantity breads novelty debate. Finally, the study also provided further evidence of the hypothesis by Agogué et al (2011) that example solutions constructed from restrictive partitions have a greater fixation affect....

  11. Evaluation of early coronary graft patency after coronary artery bypass graft surgery using multislice computed tomography angiography

    Directory of Open Access Journals (Sweden)

    Raissi Kamal

    2009-12-01

    Full Text Available Abstract Background Coronary artery bypass graft (CABG surgery is the standard of care in the treatment of advanced coronary artery disease, and its long-term results are affected by the failure of bypass grafts. The aim of the present study was to evaluate the early patency rate in coronary bypass grafts. Methods A total of 107 consecutive patients who underwent CABG were included in this study. Early graft patency was evaluated via computed tomography (CT angiography in the first week after surgery. Results There were a total of 366 grafts, comprised of 250 venous grafts and 116 arterial grafts. Multi-slice CT detected acute graft occlusions in 32 (8.7% of all the grafts, including 26 (10% of the 250 venous grafts and 6 (5% of the 116 arterial grafts. The patency rates obtained were 97.3% for the left internal mammary (IMA grafts, 50% for the radial artery grafts, and 50% for the right IMA grafts. Additionally, 107 (96.4% grafts to the left anterior descending artery (LAD were classified as patent, whereas 1 (30% of the 3 grafts in the left circumflex (LCX region and 1 (50% of the 2 grafts in the right coronary artery (RCA territory were found to be occluded. In the venous category, 8 (13.7% of the 58 grafts to LAD were found to be occluded. In the LCX region, 9 (8.5% of the 106 grafts were classified as occluded, while the remaining 97 (91.5% grafts were patent. The venous grafts to RCA were occluded in 9 (10.4% of the 86 grafts. Amongst the multiple preoperative, intraoperative, and postoperative factors, pump time was significantly longer in the patients with occluded grafts than in those with patent grafts (P = 0.04. Conclusion The IMA grafts had the highest early patency rate amongst the coronary bypass grafts. However, the other arterial grafts were associated with a high rate of acute occlusions.

  12. Combining mechanical-biological residual waste treatment plants with the carbonisation-combustion process; Kombination MBA mit dem Schwel-Brenn-Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Diekmann, J.; Wiehn, G. [Siemens AG Unternehmensbereich KWU, Erlangen (Germany). Bereich Energieerzeugung

    1998-09-01

    The disposal market for household waste is strongly influenced by the legal framework governing it. A further factor that makes it difficult for the authorities responsible for disposal to decide on residual waste disposal by means of thermal or mechanical-biological treatment plants is the downward pressure on disposal prices from inexpensive, underused landfills. This makes it all the more important for a future-oriented waste management to develop a both economically and ecologically optimised waste disposal concept. In this situation there is much in favour of adopting a concept consisting of a combination of mechanical, mechanical-biological, and thermal treatment which takes due account of waste disposal concepts at the regional and supraregional scale. [Deutsch] Der Entsorgungsmarkt fuer Siedlungsabfaelle wird stark durch die Entwicklung der rechtlichen Rahmenbedingungen beeinflusst. Hinzu kommt, dass der Entscheidungsprozess der oeffentlichen Entsorgungstraeger zur Restabfallentsorgung mittels thermischer oder mechanisch-biologischer Anlagen durch den Druck auf die Entsorgungspreise aufgrund der kostenguenstigen, nicht ausgelasteten Deponien erschwert wird. Umso mehr muss das Ziel einer zukunftsorientierten Abfallwirtschaft sein, unter oekonomischen und oekologischen Gesichtspunkten ein optimiertes Abfallkonzept aufzubauen. Hier kann es sehr hilfreich sein, sich eines Konzeptes, bestehend aus der Kombination von mechanischer, mechanisch-biologischer und thermischer Behandlung unter Beruecksichtigung des regionalen und ueberregionalen Abfallkonzeptes zu bedienen. (orig./SR)

  13. Current status of grafts and implants in rhinoplasty: Part II. Homologous grafts and allogenic implants.

    Science.gov (United States)

    Sajjadian, Ali; Naghshineh, Nima; Rubinstein, Roee

    2010-03-01

    After reading this article, the participant should be able to: 1. Understand the challenges in restoring volume and structural integrity in rhinoplasty. 2. Identify the appropriate uses of various homologous grafts and allogenic implants in reconstruction, including: (a) freeze-dried acellular allogenic cadaveric dermis grafts, (b) irradiated cartilage grafts, (c) hydroxyapatite mineral matrix, (d) silicone implants, (e) high-density polyethylene implants, (f) polytetrafluoroethylene implants, and (g) injectable filler materials. 3. Identify the advantages and disadvantages of each of these biomaterials. 4. Understand the specific techniques that may aid in the use these grafts or implants. This review specifically addresses the use of homologous grafts and allogenic implants in rhinoplasty. It is important to stress that autologous materials remain the preferred graft material for use in rhinoplasty, owing to their high biocompatibility and low risk of infection and extrusion. However, concerns of donor-site morbidity, graft availability, and graft resorption have motivated the development and use of homologous and allogenic implants.

  14. Multiple arterial grafts in coronary artery bypass grafting, Sohag University Hospital's initial experience

    Directory of Open Access Journals (Sweden)

    A.A.A. Elsayed

    2017-12-01

    Conclusions: Using multiple arterial grafts did not add a significant risk or time to the classic CABG. With accumulating evidence about better patency rate in arterial grafts, MAR is recommended especially in younger patients undergoing CABG.

  15. [Treatment of avascular necrosis of femoral head after femoral neck fracture with pedicled iliac bone graft].

    Science.gov (United States)

    Wang, Benjie; Zhao, Dewei; Guo, Lin; Yang, Lei; Li, Zhigang; Cui, Daping; Tian, Fengde; Liu, Baoyi

    2011-05-01

    To explore the effectiveness of pedicled iliac bone graft transposition for treatment of avascular necrosis of femoral head (ANFH) after femoral neck fracture. Between June 2002 and December 2006, 22 cases (22 hips, 16 left hips and 6 right hips) of ANFH after femoral neck fracture were treated with iliac bone graft pedicled with ascending branch of the lateral femoral circumflex vessels. There were 18 males and 4 females with an age range from 28 to 48 years (mean, 37.5 years). The time from injury to internal fixation was 2-31 days, and all fractures healed within 12 months after internal fixation. The ANFH was diagnosed at 15-40 months (mean, 22 months) after internal fixation. The ANFH duration was 3-11 months (mean, 8 months). According to Association Research Circulation Osseous (ARCO) staging system, 2 hips were classified as stage IIa, 3 hips as stage IIb, 3 hips as stage IIc, 3 hips as stage IIIa, 7 hips as stage IIIb, and 4 hips as stage IIIc. The preoperative Harris hip score (HHS) was 64.10 +/- 5.95. All incisions healed by first intention and the patients had no complication of lung embolism, sciatic nerve injury, lower limb deep venous thrombosis, and numbness and pain of donor site. All patients were followed up 2.5 to 6.3 years (mean, 4.8 years). The fracture healing time was 8-12 months, and no femoral neck fracture recurred. The HHS was 90.20 +/- 5.35 at last follow-up, showing significant difference when compared with the preoperative value (t = -18.447, P = 0.000). The hip function were excellent in 11 hips, good in 10 hips, fair in 1 hip, and the excellent and good rate was 95.5%. Four hips were radiographically progressed in ARCO staging, 18 hips remained stable with a stable rate of 81.8%. Pedicled iliac bone graft transposition is an ideal option for treatment of ANFH after internal fixation of femoral neck fracture for the advantages of femoral head revascularization, sufficient cancellous bone supply, and relatively simple procedure.

  16. Anterior cruciate ligament reconstruction with tibial attachment preserving hamstring graft without implant on tibial side

    Directory of Open Access Journals (Sweden)

    Skand Sinha

    2018-01-01

    Full Text Available Background: Tibial attachment preserving hamstring graft could prevent potential problems of free graft in anterior cruciate ligament (ACL reconstruction such as pull out before graft-tunnel healing or rupture before ligamentization. Different implants have been reportedly used for tibial side fixation with this technique. We investigated short-term outcome of ACL reconstruction (ACLR with tibial attachment sparing hamstring graft without implant on the tibial side by outside in technique. Materials and Methods: Seventy nine consecutive cases of ACL tear having age of 25.7 ± 6.8 years were included after Institutional Board Approval. All subjects were male. The mean time interval from injury to surgery was of 7.5 ± 6.4 months. Hamstring tendons were harvested with open tendon stripper leaving the tibial insertion intact. The free ends of the tendons were whip stitched, quadrupled, and whip stitched again over the insertion site of hamstring with fiber wire (Arthrex. Single bundle ACLR was done by outside in technique and the femoral tunnel was created with cannulated reamer. The graft was pulled up to the external aperture of femoral tunnel and fixed with interference screw (Arthrex. The scoring was done by Lysholm, Tegner, and KT 1000 by independent observers. All cases were followed up for 2 years. Results: The mean length of quadrupled graft attached to tibia was 127.65 ± 7.5 mm, and the mean width was 7.52 ± 0.78 mm. The mean preoperative Lysholm score of 47.15 ± 9.6, improved to 96.8 ± 2.4 at 1 year. All cases except two returned to the previous level of activity after ACLR. There was no significant difference statistically between preinjury (5.89 ± 0.68 and postoperative (5.87 ± 0.67 Tegner score. The anterior tibial translation (ATT (KT 1000 improved from 11.44 ± 1.93 mm to 3.59 ± 0.89 mm. The ATT of operated knee returned to nearly the similar value as of the opposite knee (3.47 ± 1.16 mm. The Pivot shift test was negative in

  17. Graft infections after surgical aortic reconstructions

    OpenAIRE

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open surgical reconstructions as first line of treatment for aorto-iliac diseases. Nowadays, open reconstructions are primarily reserved for patients unsuitable for endovascular reconstructions or for redo ...

  18. [Fusion of reconstructed titanic plate, vertebral pedical screws and autogenous granulated cancellous bone graft in posterior occipitocervical region].

    Science.gov (United States)

    Zhong, Dejun; Song, Yueming

    2006-08-01

    To explore the technique of fusing the reconstructed titanic plate, the C2 pedical screws, and the autogenous granulated cancellous bone graft in the occipitocervical region. From April 2002 to January 2005, 19 patients aged 31-67 years with occipitocervical instability underwent the occipitocervical fusion using the reconstructed plate, C2 pedical screws, and autogenous granulated cancellous bone graft. Of the patients, 8 had complex occipitocervical deformity, 8 had old atlantoaxial fracture and dislocation, 2 had rheumatoid arthritis and anterior dislocation of the atlantoaxial joint, and 1 had cancer of the deltoid process of the axis. No complication occurred during and after operation. The follow-up for an average of 16 months in 19 patients showed that all the patients achieved solid bony fusion in the occipitocervical region. There was no broken plate, broken screw, looseness of the internal fixation or neurovascular injury. The fixation of the C2 pedical screws with the reconstructed titanic plate is reliable, the insertion is easy, and the autogenous granulated cancellous bone graft has a high fusion rate, thus resulting in a satisfactory effect in the occipitocervical fusion.

  19. Outcomes of AV Fistulas and AV Grafts after Interventional Stent-Graft Deployment in Haemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Schmelter, Christopher, E-mail: christopher.schmelter@klinikum-ingolstadt.de; Raab, Udo, E-mail: udo.raab@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Diagnostic and Interventional Radiology (Germany); Lazarus, Friedrich, E-mail: friedrich.lazarus@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Nephrology (Germany); Ruppert, Volker, E-mail: volker.ruppert@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Vascular Surgery (Germany); Vorwerk, Dierk, E-mail: dierk.vorwerk@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Diagnostic and Interventional Radiology (Germany)

    2015-08-15

    PurposeThe study was designed to assess outcomes of arteriovenous (AV) accesses after interventional stent-graft deployment in haemodialysis patients.Materials and Methods63 haemodialysis patients with 66 AV fistulas and AV grafts were treated by interventional stent-graft deployment from 2006 to 2012 at our hospital. Data of these patients were retrospectively analysed for location of deployed stent-grafts, occurrence and location of (re-)stenosis and (re-)thrombosis. Complex stenosis was the most frequent indication for stent-graft deployment (45.5 %), followed by complications of angioplasty with vessel rupture or dissection (31.8 %).ResultsA high rate of procedural success was achieved (98.5 %). The most frequent location of the deployed stent-graft was the draining vein (66.7 %). Stent-graft deployment was more frequent in AV grafts than in AV fistulas. Primary patency was 45.5 % at 6 month, 31.3 % at 12 month and 19.2 % at 24 month. Primary patency was significantly better for AV fistulas than for AV grafts with deployed stent-grafts. Patency of the deployed stent-graft was much better than overall AV access primary patency with deployed stent-graft. Re-stenosis with thrombosis was the most frequent indication for re-intervention. Most frequent location of re-stenosis was the draining vein (37.1 %), followed by stenosis at the AV access (29.5 %) and the deployed stent-graft (23.5 %).ConclusionRe-stenosis and re-thrombosis remain frequent in AV fistulas and AV grafts in haemodialysis patients despite stent-graft deployment. Re-stenosis of the deployed stent-graft is, only in the minority of the cases, responsible for AV access dysfunction.

  20. Percutaneous anterior C1/2 transarticular screw fixation: salvage of failed percutaneous odontoid screw fixation for odontoid fracture

    OpenAIRE

    Wu, Ai-Min; Jin, Hai-Ming; Lin, Zhong-Ke; Chi, Yong-Long; Wang, Xiang-Yang

    2017-01-01

    Background The objective of this study is to investigate the outcomes and safety of using percutaneous anterior C1/2 transarticular screw fixation as a salvage technique for odontoid fracture if percutaneous odontoid screw fixation fails. Methods Fifteen in 108 odontoid fracture patients (planned to be treated by percutaneous anterior odontoid screw fixation) were failed to introduce satisfactory odontoid screw trajectory. To salvage this problem, we chose the percutaneous anterior C1/2 trans...

  1. Nuclear accidents and bone marrow graft

    International Nuclear Information System (INIS)

    Bernard, J.

    1988-01-01

    In case of serious contamination, the only efficacious treatment is the bone marrow grafts. The graft types and conditions have been explained. To restrict the nuclear accidents consequences, it is recommended to: - take osseous medulla of the personnel exposed to radiations and preserve it , that permits to carry out rapidly the auto-graft in case of accidents; - determine, beforehand, the HLA group of the personnel; - to register the voluntary donors names and addresses, and their HLA group, that permits to find easily a compatible donar in case of allo-graft. (author)

  2. Free fibular strut graft in neglected femoral neck fractures in adult

    Directory of Open Access Journals (Sweden)

    Azam Md Quamar

    2009-01-01

    Full Text Available Background: Neglected femoral neck fracture in adults still poses a formidable challenge. Existing treatment options varies from osteotomy (with or without graft to osteosynthesis using various implants and grafting techniques (muscle pedicle, vascularized, and nonvascularized fibula. The aim of this study was to assess outcome of nonvascularized fibular strut graft and cancellous screw fixation in neglected femoral neck fractures in the younger age group. Materials and Methods: Medical records of 32 patients of neglected femoral neck fracture, in the age group of 22-45 years (mean 37.8 years, operated between May 1994 to December 2001, were retrospectively reviewed. After the application of inclusion and exclusion criteria, 28 patients having three years minimum follow-up (mean 4.6 years were included. Delay between injury and operation varied from four weeks to 42 weeks (mean 16.4 weeks. Closed reduction was achieved in 17 patients; open reduction through Watson-Jones anterolateral approach was performed in the remaining 15 patients in whom closed reduction failed. The fracture was transfixed with three parallel guide wires. Appropriate sized cannulated lag screw (7 mm was then inserted in two of the wires. Selection of the third guide wire for fibula depended on the space available in both anteroposterior and lateral view. Results: Satisfactory bony union was obtained in 25 patients, of whom in four cases, the union occurred in 10-20° (mean 15° of varus. Nonunion occurred in three patients (9.37%, and aseptic necrosis occurred in another six patients (18.75%. Of the 25 patients where union was achieved, five patients showed excellent results; 14 good and six had poor functional result, as evaluated using modified Anglen criteria. Conclusion: Nonvascularized fibular strut graft along with cancellous screws provides a dependable and technically less-demanding alternative procedure for neglected femoral neck fractures in young adults. Fibula

  3. Anatomical reconstruction of the fourth brachymetatarsia with one-stage iliac bone and cartilage cap grafting.

    Science.gov (United States)

    Woo, Sang Hyun; Bang, Chi Young; Ahn, Hee-Chan; Kim, Sung-Jung; Choi, Jun-Young

    2017-05-01

    We present a one-stage procedure for lengthening the fourth brachymetatarsia with autogenous iliac bone and cartilage cap grafting for the anatomical reconstruction of the metatarsophalangeal (MTP) joint METHODS: During the last 8 years, 56 feet in 41 patients with congenital brachymetatarsia of the fourth toe were corrected with a one-stage operation to reposition the articular cartilage cap to the distal part of interpositional iliac bone graft at the metatarsal epiphysis. The length of the harvested iliac bone graft was 22.9 mm on average. The mean fixation period was 58.5 days, and the mean gain in length and percentage increase was 20.9 mm and 39%, respectively. MRI showed a stable MTP joint over viable cartilage cap in 83.3% of the cases. Mean postoperative American Orthopedic Foot and Ankle Society lesser MTP-interphalangeal score was 82.0. Neither neurovascular impairment nor recurrence of brachymetatarsia occurred in the mean follow-up period of 43.6 months. All patients were satisfied with the postoperative cosmetic results. Thirteen patients (23.2%) complained of limited active dorsiflexion of the fourth toe, and extensor adhesion was released by extensor tenolysis in only one patient. In a single case of nonunion at the bone graft site, additional surgery was not necessary. Anatomical reconstruction of the fourth brachymetatarsia with one-stage interpositional iliac bone and cartilage cap grafting resulted in excellent cosmetic results and a physiologic MTP joint, providing the benefits of one-stage lengthening with a low complication rate. Therapeutic, IV. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  4. Graft union formation in artichoke grafting onto wild and cultivated cardoon: an anatomical study.

    Science.gov (United States)

    Trinchera, Alessandra; Pandozy, Gianmarco; Rinaldi, Simona; Crinò, Paola; Temperini, Olindo; Rea, Elvira

    2013-12-15

    In order to develop a non-chemical method such as grafting effective against well-known artichoke soil borne diseases, an anatomical study of union formation in artichoke grafted onto selected wild and cultivated cardoon rootstocks, both resistant to Verticillium wilt, was performed. The cardoon accessions Belgio (cultivated cardoon) and Sardo (wild cardoon) were selected as rootstocks for grafting combinations with the artichoke cv. Romolo. Grafting experiments were carried out in the autumn and spring. The anatomical investigation of grafting union formation was conducted by scanning electron microscopy (SEM) on the grafting portions at the 3rd, 6th, 10th, 12th day after grafting. For the autumn experiment only, SEM analysis was also performed at 30 d after grafting. A high affinity between artichoke scion and cardoon rootstocks was observed, with some genotype differences in healing time between the two bionts. SEM images of scion/rootstock longitudinal sections revealed the appearance of many interconnecting structures between the two grafting components just 3d after grafting, followed by a vascular rearrangement and a callus development during graft union formation. De novo formation of many plasmodesmata between scion and rootstock confirmed their high compatibility, particularly in the globe artichoke/wild cardoon combination. Moreover, the duration of the early-stage grafting process could be influenced not only by the scion/rootstock compatibility, but also by the seasonal conditions, being favored by lower temperatures and a reduced light/dark photoperiod. Copyright © 2013 Elsevier GmbH. All rights reserved.

  5. Biomechanics of lumbar cortical screw-rod fixation versus pedicle screw-rod fixation with and without interbody support.

    Science.gov (United States)

    Perez-Orribo, Luis; Kalb, Samuel; Reyes, Phillip M; Chang, Steve W; Crawford, Neil R

    2013-04-15

    Seven different combinations of posterior screw fixation, with or without interbody support, were compared in vitro using nondestructive flexibility tests. To study the biomechanical behavior of a new cortical screw (CS) fixation construct relative to the traditional pedicle screw (PS) construct. The CS is an alternative to the PS for posterior fixation of the lumbar spine. The CS trajectory is more sagittally and cranially oriented than the PS, being anchored in the pars interarticularis. Like PS fixation, CS fixation uses interconnecting rods fastened with top-locking connectors. Stability after bilateral CS fixation was compared with stability after bilateral PS fixation in the setting of intact disc and with direct lateral interbody fixation (DLIF) or transforaminal lateral interbody fixation (TLIF) support. Standard nondestructive flexibility tests were performed in cadaveric lumbar specimens, allowing non-paired comparisons of specific conditions from 28 specimens (4 groups of 7) within a larger experiment of multiple hardware configurations. Condition tested and group from which results originated were as follows: (1) intact (all groups); (2) with L3-L4 bilateral PS-rods (group 1); (3) with bilateral CS-rods (group 2); (4) with DLIF (group 3); (5) with DLIF + CS-rods (group 4); (6) with DLIF + PS-rods (group 3); (7) with TLIF + CS-rods (group 2), and (8) with TLIF + PS-rods (group 2). To assess spinal stability, the mean range of motion, lax zone, and stiff zone at L3-L4 were compared during flexion-extension, lateral bending, and axial rotation. With intact disc, stability was equivalent after PS-rod and CS-rod fixation, except that PS-rod fixation was stiffer during axial rotation. With DLIF support, there was no significant difference in stability between PS-rod and CS-rod fixation. With TLIF support, PS-rod fixation was stiffer than CS-rod fixation during lateral bending. Bilateral CS-rod fixation provided about the same stability in cadaveric specimens

  6. Internal Versus External Fixation of Charcot Midfoot Deformity Realignment.

    Science.gov (United States)

    Lee, Daniel J; Schaffer, Joseph; Chen, Tien; Oh, Irvin

    2016-07-01

    Internal and external fixation techniques have been described for realignment and arthrodesis of Charcot midfoot deformity. There currently is no consensus on the optimal method of surgical reconstruction. This systematic review compared the clinical results of surgical realignment with internal and external fixation, specifically in regard to return to functional ambulation, ulcer occurrence, nonunion, extremity amputation, unplanned further surgery, deep infection, wound healing problems, peri- or intraoperative fractures, and total cases with any complication. A search of multiple databases for all relevant articles published from January 1, 1990, to March 22, 2014, was performed. A logistic regression model evaluated each of the outcomes and its association with the type of fixation method. The odds of returning to functional ambulation were 25% higher for internal fixation (odds ratio [OR], 1.259). Internal fixation had a 42% reduced rate of ulcer occurrence (OR, 0.578). External fixation was 8 times more likely to develop radiographic nonunion than internal fixation (OR, 8.2). Internal fixation resulted in a 1.5-fold increase in extremity amputation (OR, 1.488), a 2-fold increase in deep infection (OR, 2.068), a 3.4-fold increase in wound healing complications (OR, 3.405), and a 1.5-fold increase in the total number of cases experiencing any complication (OR, 1.525). This was associated with a 20% increase in the need for unplanned further surgery with internal fixation (OR, 1.221). Although internal fixation may decrease the risk of nonunion and increase return to functional ambulation, it had a higher rate of overall complications than external fixation for realignment and arthrodesis of Charcot midfoot deformity. [Orthopedics. 2016; 39(4):e595-e601.]. Copyright 2016, SLACK Incorporated.

  7. Fixation Strength of Polyetheretherketone Sheath-and-Bullet Device for Soft Tissue Repair in the Foot and Ankle.

    Science.gov (United States)

    Christensen, Jay; Fischer, Brian; Nute, Michael; Rizza, Robert

    Tendon transfers are often performed in the foot and ankle. Recently, interference screws have been a popular choice owing to their ease of use and fixation strength. Considering the benefits, one disadvantage of such devices is laceration of the soft tissues by the implant threads during placement that potentially weaken the structural integrity of the grafts. A shape memory polyetheretherketone bullet-in-sheath tenodesis device uses circumferential compression, eliminating potential damage from thread rotation and maintaining the soft tissue orientation of the graft. The aim of this study was to determine the pullout strength and failure mode for this device in both a synthetic bone analogue and porcine bone models. Thirteen mature bovine extensor tendons were secured into ten 4.0 × 4.0 × 4.0-cm cubes of 15-pound per cubic foot solid rigid polyurethane foam bone analogue models or 3 porcine femoral condyles using the 5 × 20-mm polyetheretherketone soft tissue anchor. The bullet-in-sheath device demonstrated a mean pullout of 280.84 N in the bone analog models and 419.47 N in the porcine bone models. (p = .001). The bullet-in-sheath design preserved the integrity of the tendon graft, and none of the implants dislodged from their original position. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  8. 2-octyl-cyanoacrylate glue for fixation of STSG in genitourinary tissue defects due to Fournier gangrene: a preliminary trial.

    Science.gov (United States)

    Sivrioğlu, Nazan; Irkören, Saime; Ceylan, Ender; Sonel, Ali Murat; Copçu, Eray

    2013-05-01

    In these reported cases, we observed the outcomes of skin take and wound healing using 2-octyl-cyanoacrylate glue, which was used as tissue glue in the reconstruction of complex genital skin loss due to fournier gangrene. Fifteen patients with Fournier's gangrene were treated in this study. After initial surgical debridement, all defects were repaired using STSG. In this method a thin layer of 2-octyl-cyanoacrylate was dripped on the recipient site immediately before graft application. All wounds were followed up postoperatively and observed for evidence of graft take, seroma or hematoma formation, drainage, and infection. Patient and physician satisfaction were also determined. Grafts were completely accepted in all fifteen patients. None of the patients had wound infection, seroma, hematoma, or other complications. Use of 2-octyl-cyanoacrylate glue (Glueseal) for STSG fixation in complex genital skin defects after Fournier gangrene may be an acceptable alternative to conventional surgical closure with a good cosmetic outcome. Further studies are needed to confirm our initial success with this approach.

  9. Lymphoid Tissue Grafts in Man

    Energy Technology Data Exchange (ETDEWEB)

    Kay, H. E.M. [Royal Marsden Hospital, Institute of Cancer Research, London (United Kingdom)

    1969-07-15

    Grafts of lymphoid tissue or of lymphoid stem cells may be appropriate in the treatment of some congenital immune deficiency disorders. The reasons for preferring tissues of foetal origin are discussed and the evidence for foetal immunocompetence is briefly summarized. Methods of storing foetal liver cells and cells or fragments of thymus are mentioned, and the organization of the Foetal Tissue Bank of the Royal Marsden Hospital is described. Clinical data from transplantation of lymphoid cells in various immune deficiency disorders are briefly presented. (author)

  10. Development of sodium alginate and konkoli gum- grafted ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-02

    May 2, 2008 ... grafted-polyacrylamide blend membrane: optimization of grafting conditions .... medium and reduce rate of termination by the coupling of the growing ... Effect of time. The time conversion curve of the graft copolymerization ...

  11. Industrial application of electron beams for grafting and vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1994-12-31

    The topics discussed are radiation graft polymerization; industrial application of radiation grafting - ion exchange membrane for a battery separator, ammonia adsorbent, non-flammable PE (polyethylene) foam; R and D on radiation grafting, radiation vulcanization of natural rubber.

  12. Industrial application of electron beams for grafting and vulcanization

    International Nuclear Information System (INIS)

    Keizo Makuuchi

    1994-01-01

    The topics discussed are radiation graft polymerization; industrial application of radiation grafting - ion exchange membrane for a battery separator, ammonia adsorbent, non-flammable PE (polyethylene) foam; R and D on radiation grafting, radiation vulcanization of natural rubber

  13. Effect of bidispersity in grafted chain length on grafted chain conformations and potential of mean force between polymer grafted nanoparticles in a homopolymer matrix.

    Science.gov (United States)

    Nair, Nitish; Wentzel, Nathaniel; Jayaraman, Arthi

    2011-05-21

    In efforts to produce polymeric materials with tailored physical properties, significant interest has grown around the ability to control the spatial organization of nanoparticles in polymer nanocomposites. One way to achieve controlled particle arrangement is by grafting the nanoparticle surface with polymers that are compatible with the matrix, thus manipulating the interfacial interactions between the nanoparticles and the polymer matrix. Previous work has shown that the molecular weight of the grafted polymer, both at high grafting density and low grafting density, plays a key role in dictating the effective inter-particle interactions in a polymer matrix. At high grafting density nanoparticles disperse (aggregate) if the graft molecular weight is higher (lower) than the matrix molecular weight. At low grafting density the longer grafts can better shield the nanoparticle surface from direct particle-particle contacts than the shorter grafts and lead to the dispersion of the grafted particles in the matrix. Despite the importance of graft molecular weight, and evidence of non-trivial effects of polydispersity of chains grafted on flat surfaces, most theoretical work on polymer grafted nanoparticles has only focused on monodisperse grafted chains. In this paper, we focus on how bidispersity in grafted chain lengths affects the grafted chain conformations and inter-particle interactions in an implicit solvent and in a dense homopolymer polymer matrix. We first present the effects of bidispersity on grafted chain conformations in a single polymer grafted particle using purely Monte Carlo (MC) simulations. This is followed by calculations of the potential of mean force (PMF) between two grafted particles in a polymer matrix using a self-consistent Polymer Reference Interaction Site Model theory-Monte Carlo simulation approach. Monte Carlo simulations of a single polymer grafted particle in an implicit solvent show that in the bidisperse polymer grafted particles

  14. Improvement of polymer stability by radiation grafting

    International Nuclear Information System (INIS)

    Ranogajec, F.; Mlinac-Misak, M.

    1999-01-01

    Losses of the stabilizer due to extractability or volatility immediately affect ultimate performance of polymer product. A new approach to increase the persistence of the stabilizer in the final product is to chemically bind it to the polymer backbone. Radiation grafting or crosslinking could be an efficient method for this, when the stabilizer is polymerizable. By a mutual gamma irradiation method, photoprotector 2-hydroxy-4-(3-methacryloxy-2- hydroxy-propoxy) benzophenone (HMB) has been readily grafted to low density polyethylene (LDPE) in benzene, tetrahydrofuran and methanol solution, respectively. Surface grafting occurs in a methanol solution of stabilizer, while in benzene and tetrahydrofuran solutions of stabilizer, grafting proceeds more or less in the inner parts of the polymeric film as well. The grafted LDPE film in methanol and tetrahydrofuran (containing 1 w/w % of grafted HMB), 1 w/w % blended HMB with LDPE and nongrafted LDPE film, were all exposed to accelerated aging and natural weathering and their spectral changes, expressed by the carbonyl index, were then compared. The change of elongation at break and tensile strength were measured in the course of aging. UV stability tests on aged films and change in mechanical properties indicate a pronounced protective effect achieved by grafted stabilizer. Grafting in methanol solution appears to be an efficient photostabilization treatment and the most economical with respect to the consumption of monomer, the grafting yield being less than 0.5%. Surface grafting is an efficient photostabilization method since grafted stabilizer is chemically bound to a polymeric surface and in this way the problem of evaporation of blended stabilizers during the prolonged use of polymeric materials is eliminated. (author)

  15. Meta-analysis of Renal Function Following Infrarenal EVAR using Suprarenal or Infrarenal Fixation Devices.

    Science.gov (United States)

    Stather, Philip W; Ferguson, James; Awopetu, Ayoola; Boyle, Jonathan R

    2018-03-03

    The effect of suprarenal (SR) as opposed to infrarenal (IR) fixation on renal outcomes post-endovascular aneurysm repair (EVAR) remains controversial. This meta-analysis aims to update current understanding of this issue. A prior meta-analysis was updated through a Preferred Reporting Items for Systematic reviews and Meta-Analyses search for additional studies published in the last 3 years reporting on renal dysfunction or related outcomes post-EVAR. Random effects meta-analysis was undertaken using SPSS. A total of 25 non-randomised studies comparing SR with IR fixation were included, totalling 54,832 patients. In total, 16,634 underwent SR and 38,198 IR. Baseline characteristics, including age, baseline estimated glomerular filtration rate, diabetes, cardiac disease, and smoking, were similar between the groups. There was a small but significant difference in outcomes for renal dysfunction at the study end point (SR 5.98% vs. IR 4.83%; odds ratio [OR] 1.29, 95% confidence interval [CI] 1.18-1.40 [p analysis. Incidence of renal infarcts (SR 6.6% vs. IR 2.3%; OR 2.78, 95% CI 1.46-5.29 [p = .002]), renal stenosis (SR 2.4% vs. IR 0.8%; OR 2.89, 95% CI 1.00-8.38 [p = .05]), and renal artery occlusion (SR 2.4% vs. IR 1.2%; OR 2.21, 95% CI 1.15-4.25 [p = 0.02]) favoured IR fixation; however, there was no difference in haemodialysis rates. This meta-analysis has identified small but significantly worse renal outcomes in patients having SR fixation devices compared with IR; however, there was no difference in dialysis rates and a small effect on renal dysfunction, which did not stand up to rigorous sensitivity analysis. This should be taken into consideration during graft selection, and further studies must assess renal outcomes in the longer term, and in those with pre-existing renal dysfunction. Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.

  16. Sacroiliac screw fixation: A mini review of surgical technique

    Directory of Open Access Journals (Sweden)

    Hernando Raphael Alvis-Miranda

    2014-01-01

    Full Text Available The sacral percutaneous fixation has many advantages but can be associated with a significant exposure to X-ray radiation. Currently, sacroiliac screw fixation represents the only minimally invasive technique to stabilize the posterior pelvic ring. It is a technique that should be used by experienced surgeons. We present a practical review of important aspects of this technique.

  17. Customizable rigid head fixation for infants: technical note.

    Science.gov (United States)

    Udayakumaran, Suhas; Onyia, Chiazor U

    2016-01-01

    The need and advantages of rigid fixation of the head in cranial surgeries are well documented (Berryhill et al., Otolaryngol Head Neck Surg 121:269-273, 1999). Head fixation for neurosurgical procedures in infants and in early years has been a challenge and is fraught with risk. Despite the fact that pediatric pins are designed, rigid head fixation involving direct application of pins to the head of infants and slightly older children is still generally not safe (Agrawal and Steinbok, Childs Nerv Syst 22:1473-1474, 2006). Yet, there are some surgeries in which some form of rigid fixation is required (Agrawal and Steinbok, Childs Nerv Syst 22:1473-1474, 2006). We describe a simple technique to achieve rigid fixation of the head in infants for neurosurgical procedures. This involves applying a head band made of Plaster of Paris (POP) around the head and then applying the fixation pins of the fixation frame directly on to the POP. We have used this technique of head fixation successfully for infants with no complications.

  18. 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 ...

  19. Indications and outcome of Open Reduction and Internal Fixation of ...

    African Journals Online (AJOL)

    Background: Open reduction and internal fixation (ORIF) is a well-established surgical treatment of fractures worldwide. However, the indications and modes of stabilization of long bone fractures vary and are evolving .The general trend now is towards fixation with locked intramedullary nail (i.m nail) rather than plate and ...

  20. Predicting Eye Fixations on Complex Visual Stimuli Using Local Symmetry.

    Science.gov (United States)

    Kootstra, Gert; de Boer, Bart; Schomaker, Lambert R B

    2011-03-01

    Most bottom-up models that predict human eye fixations are based on contrast features. The saliency model of Itti, Koch and Niebur is an example of such contrast-saliency models. Although the model has been successfully compared to human eye fixations, we show that it lacks preciseness in the prediction of fixations on mirror-symmetrical forms. The contrast model gives high response at the borders, whereas human observers consistently look at the symmetrical center of these forms. We propose a saliency model that predicts eye fixations using local mirror symmetry. To test the model, we performed an eye-tracking experiment with participants viewing complex photographic images and compared the data with our symmetry model and the contrast model. The results show that our symmetry model predicts human eye fixations significantly better on a wide variety of images including many that are not selected for their symmetrical content. Moreover, our results show that especially early fixations are on highly symmetrical areas of the images. We conclude that symmetry is a strong predictor of human eye fixations and that it can be used as a predictor of the order of fixation.

  1. Femoral fractures : indications an[d] biomechanics of external fixation

    NARCIS (Netherlands)

    A.H. Broekhuizen (Tom); B. van Linge

    1988-01-01

    textabstractInternal fixation can be carried out in various ways. For femoral shaft fractures, an (interlocking) nail is becoming increasingly popular, instead of open realignment of the fracture. External fixation, which has become a generally accepted method of treating fractures of the lower

  2. Application of monorail fixator for femoral gap nonunion.

    Science.gov (United States)

    Agrawal, Hemendra-Kumar; Jaiman, Ashish; Khatkar, Vipin; Sharma, Vinod-Kumar

    2014-01-01

    Difficult femoral nonunion takes account of infective nonunion and aseptic gap nonunion. Limb length discrepancy and nonunion need to be tackled simultaneously. Conventionally Ilizarov ring fixator is in vogue but it has some limitations. To overcome these, monorail fixator is an effective alternative. Persistent good results can be obtained if we can get a perfect anatomical alignment and good regeneration.

  3. Predicting Eye Fixations on Complex Visual Stimuli Using Local Symmetry

    NARCIS (Netherlands)

    Kootstra, Geert; de Boer, Bart; Schomaker, Lambertus

    Most bottom-up models that predict human eye fixations are based on contrast features. The saliency model of Itti, Koch and Niebur is an example of such contrast-saliency models. Although the model has been successfully compared to human eye fixations, we show that it lacks preciseness in the

  4. Predicting eye fixations on complex visual stimuli using local symmetry

    NARCIS (Netherlands)

    Kootstra, G.; de Boer, B.; Schomaker, L.R.B.

    2011-01-01

    Most bottom-up models that predict human eye fixations are based on contrast features. The saliency model of Itti, Koch and Niebur is an example of such contrast-saliency models. Although the model has been successfully compared to human eye fixations, we show that it lacks preciseness in the

  5. [Treatment of femoral neck fracture--preference to internal fixation].

    Science.gov (United States)

    Minato, Izumi

    2011-03-01

    In the guidelines for the treatment of femoral neck fracture, prosthetic replacement is recommended in displaced one and internal fixation is in undisplaced one. However, in the long view, survived femoral head after internal fixation can be superior to prosthesis which will deteriorate as time goes by. Surgical method should be considered not only by type of fracture but general status of the patient.

  6. Biodegradability of poly(3-hydroxybutyrate) film grafted with vinyl acetate: Effect of grafting and saponification

    Science.gov (United States)

    Wada, Yuki; Seko, Noriaki; Nagasawa, Naotsugu; Tamada, Masao; Kasuya, Ken-ichi; Mitomo, Hiroshi

    2007-06-01

    Radiation-induced graft polymerization of vinyl acetate (VAc) onto poly(3-hydroxybutyrate) (PHB) film was carried out. At a degree of grafting higher than 5%, the grafted films (PHB-g-VAc) completely lost the enzymatic degradability that is characteristic of PHB due to the grafted VAc covering the surface of the PHB film. However, the biodegradability of the PHB-g-VAc films was recovered when the films were saponified in alkali solution under optimum conditions. Graft chains of the PHB-g-VAc film reacted selectively to become biodegradable polyvinyl alcohol (PVA). The biodegradability of the saponified PHB-g-VAc film increased rapidly with time.

  7. Biodegradability of poly(3-hydroxybutyrate) film grafted with vinyl acetate: Effect of grafting and saponification

    International Nuclear Information System (INIS)

    Wada, Yuki; Seko, Noriaki; Nagasawa, Naotsugu; Tamada, Masao; Kasuya, Ken-ichi; Mitomo, Hiroshi

    2007-01-01

    Radiation-induced graft polymerization of vinyl acetate (VAc) onto poly(3-hydroxybutyrate) (PHB) film was carried out. At a degree of grafting higher than 5%, the grafted films (PHB-g-VAc) completely lost the enzymatic degradability that is characteristic of PHB due to the grafted VAc covering the surface of the PHB film. However, the biodegradability of the PHB-g-VAc films was recovered when the films were saponified in alkali solution under optimum conditions. Graft chains of the PHB-g-VAc film reacted selectively to become biodegradable polyvinyl alcohol (PVA). The biodegradability of the saponified PHB-g-VAc film increased rapidly with time

  8. Tightrope fixation of ankle syndesmosis injuries: clinical outcome, complications and technique modification.

    LENUS (Irish Health Repository)

    Naqvi, Gohar A

    2012-06-01

    Ankle syndesmotic injuries are complex and require anatomic reduction and fixation. Tightrope fixation is a relatively new technique and we present the largest series of syndesmosis fixation using Arthrex Tightrope™ (Naples, FL, USA).

  9. Fixation and escape times in stochastic game learning

    International Nuclear Information System (INIS)

    Realpe-Gomez, John; Szczesny, Bartosz; Galla, Tobias; Dall’Asta, Luca

    2012-01-01

    Evolutionary dynamics in finite populations is known to fixate eventually in the absence of mutation. We here show that a similar phenomenon can be found in stochastic game dynamical batch learning, and investigate fixation in learning processes in a simple 2×2 game, for two-player games with cyclic interaction, and in the context of the best-shot network game. The analogues of finite populations in evolution are here finite batches of observations between strategy updates. We study when and how such fixation can occur, and present results on the average time-to-fixation from numerical simulations. Simple cases are also amenable to analytical approaches and we provide estimates of the behaviour of so-called escape times as a function of the batch size. The differences and similarities with escape and fixation in evolutionary dynamics are discussed. (paper)

  10. Nanofat grafting under a split-thickness skin graft for problematic wound management.

    Science.gov (United States)

    Kemaloğlu, Cemal Alper

    2016-01-01

    Obesity and certain medical disorders make the reconstruction of skin defects challenging. Different kind of procedure can be used for these defect, besides, skin grafting is one of the most common and simplest procedure. Fat grafting and stem cells which are located in the adipose tissue have been commonly used in plastic surgery for regeneration and rejuvenation purposes. To decrease graft failure rate we performed nanofat grafting under an autologous split-thickness skin graft in our patient who had a problematic wound. The case of a 35-year-old female patient with a traumatic skin defect on her left anterior crural region is described herein. After subsequent flap reconstruction, the result was disappointing and the defect size was widened. The defect was treated with combined grafting (nanofat grafting under an autologous split-thickness skin graft). At the 6 months follow-up assessment after combined grafting, the integrity of the skin graft was good with excellent pliability. Combined grafting for problematic wounds seems to be a useful technique for cases requiring reconstruction. The potential existence of stem cells may be responsible for the successful result in our patient.

  11. Emerging concepts in liver graft preservation

    Science.gov (United States)

    Bejaoui, Mohamed; Pantazi, Eirini; Folch-Puy, Emma; Baptista, Pedro M; García-Gil, Agustín; Adam, René; Roselló-Catafau, Joan

    2015-01-01

    The urgent need to expand the donor pool in order to attend to the growing demand for liver transplantation has obliged physicians to consider the use of suboptimal liver grafts and also to redefine the preservation strategies. This review examines the different methods of liver graft preservation, focusing on the latest advances in both static cold storage and machine perfusion (MP). The new strategies for static cold storage are mainly designed to increase the fatty liver graft preservation via the supplementation of commercial organ preservation solutions with additives. In this paper we stress the importance of carrying out effective graft washout after static cold preservation, and present a detailed discussion of the future perspectives for dynamic graft preservation using MP at different temperatures (hypothermia at 4 °C, normothermia at 37 °C and subnormothermia at 20 °C-25 °C). Finally, we highlight some emerging applications of regenerative medicine in liver graft preservation. In conclusion, this review discusses the “state of the art” and future perspectives in static and dynamic liver graft preservation in order to improve graft viability. PMID:25593455

  12. Dynamics of solvent-free grafted nanoparticles

    KAUST Repository

    Chremos, Alexandros; Panagiotopoulos, Athanassios Z.; Koch, Donald L.

    2012-01-01

    as well as grafted nanoparticles in a melt were compared to a reference system of bare (ungrafted) particles in a melt. Whereas longer chains lead to a larger hydrodynamic radius and lower relative diffusivity for grafted particles in a melt, bulk solvent

  13. The effect of monomer molecular weight on grafting reaction

    International Nuclear Information System (INIS)

    Wu Minghong; Ding Zhongli; Ma Zueteh

    1995-01-01

    In this paper, some condensed ethylene glycol acrylate monomers with different molecular weight being grafted to the PE film by means of pre-irradiation is reported. The effect of molecular weight of monomer on grafting reaction and the hydrophilicity of grafting sample have been discussed. The experimental results show: molar degrees of grafting decreased non-linearly with the increasement of molecular weight of monomer, the grafting reaction of polymer is greater effected by the swelling degree of PE film, the greater the swelling degree of grafting material, the higher the grating degree grafting is, the initial rate of grafting reaction decreased with the increasement of molecular weight of monomer. (author)

  14. Directional tip control technique for optimal stent graft alignment in angulated proximal aortic landing zones

    Directory of Open Access Journals (Sweden)

    Toshio Takayama, MD, PhD

    2017-06-01

    Full Text Available Angulated anatomy in the aorta, such as tortuous infrarenal aortic necks or steep aortic arches, is a significant challenge for endovascular aortic repair because it often causes inadequate sealing and fixation, which may lead to treatment failure. We have developed a technique using off-the-shelf equipment to precisely control the deployment of stent grafts in challenging landing zones. The key of this technique is to create a through-and-through wire between two access sites and to use a guiding device over the wire. This technique is best used with stent grafts without nose cones. We present an endovascular aneurysm repair case and a thoracic endovascular aortic repair case with challenging proximal landing zones treated by this technique. In both cases, technical success was attained, and follow-up imaging demonstrated well-aligned stent grafts. Our directional tip control technique is easy and effective. It can be a good technical solution for endovascular aortic treatment in angulated anatomy.

  15. Les aciers inoxydables dans les fixations

    CERN Document Server

    CETIM

    2010-01-01

    Cet ouvrage, qui fait la synthèse de plusieurs travaux menés par le Cetim, propose une vue d'ensemble sur les aciers inoxydables utilisés pour les fixations. Au sommaire : les normes EN, ISO et ATSM qui s'y rapportent , les désignations symboliques , les nuances et caractéristiques mécaniques , les différentes formes de corrosion, les méthodes pour les détecter , les règles du métier , les mises en oeuvre. L'ouvrage comprend plusieurs fiches matériaux et des tableaux qui présentent les équivalences entre les désignations.

  16. Nitrogen fixation by legumes in retorted shale

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L E; Molitoris, E; Klein, D A

    1981-01-01

    Although a soil-shale mixture was employed as the growth medium in this experiment, the results presentd are applicable to the proposed method of disposal mentioned earlier. Under field conditions, when covering the retorted shale with topsoil, some mixing of these materials might occur in the plant root region. In addition, it has been demonstrated that buried shale negatively affects enzyme activities in overburden surface soil. The occurrence of either of those events could affect symbiotic N/sub 2/ fixation in a manner similar to that reported in this paper. Researchers conclude that due to the varied effects of retorted shale on the legumes tested, further evaluation of other legumes may be necessary. Additional research would be required to determine which legumes have potential use for reclamation of retorted shale.

  17. Do you like what you see? The role of first fixation and total fixation duration in consumer choice

    NARCIS (Netherlands)

    Laan, van der L.N.; Hooge, I.T.C.; Ridder, de D.T.D.; Viergever, M.A.; Smeets, P.A.M.

    2015-01-01

    Although there has been recent growing interest in the associations between measures of visual attention and consumer choice, there is still uncertainty about the role of the first fixation in consumer choice and the factors that drive total fixation duration. The study aimed (1) to investigate the

  18. External Fixation versus two-stage Open Reduction Internal Fixation of distal intra-articular Tibia fractures; a Systematic Review

    DEFF Research Database (Denmark)

    Ladeby Erichsen, Julie; Jensen, Carsten; Damborg, Frank Lindhøj

    Internal Fixation (ORIF) or External Fixation (EF). Method : A search was conducted using PUBMED, Embase, Cochrane Central, Open Grey, Orthopaedic Proceedings and WHO International Clinical Trials Registry Platform. Studies with level of evidence I-IV comparing EF with two-stage ORIF of DIATF in patients...

  19. Do you like what you see? : The role of first fixation and total fixation duration in consumer choice

    NARCIS (Netherlands)

    van der Laan, Laura N.; Hooge, Ignace T C; De Ridder, Denise T D; Viergever, Max A.; Smeets, Paul A M

    2015-01-01

    Although there has been recent growing interest in the associations between measures of visual attention and consumer choice, there is still uncertainty about the role of the first fixation in consumer choice and the factors that drive total fixation duration. The study aimed (1) to investigate the

  20. A Meta-Analysis for Postoperative Complications in Tibial Plafond Fracture: Open Reduction and Internal Fixation Versus Limited Internal Fixation Combined With External Fixator.

    Science.gov (United States)

    Wang, Dong; Xiang, Jian-Ping; Chen, Xiao-Hu; Zhu, Qing-Tang

    2015-01-01

    The treatment of tibial plafond fractures is challenging to foot and ankle surgeons. Open reduction and internal fixation and limited internal fixation combined with an external fixator are 2 of the most commonly used methods of tibial plafond fracture repair. However, conclusions regarding the superior choice remain controversial. The present meta-analysis aimed to quantitatively compare the postoperative complications between open reduction and internal fixation and limited internal fixation combined with an external fixator for tibial plafond fractures. Nine studies with 498 fractures in 494 patients were included in the present study. The meta-analysis found no significant differences in bone healing complications (risk ratio [RR] 1.17, 95% confidence interval [CI] 0.68 to 2.01, p = .58], nonunion (RR 1.09, 95% CI 0.51 to 2.36, p = .82), malunion or delayed union (RR 1.24, 95% CI 0.57 to 2.69, p = .59), superficial (RR 1.56, 95% CI 0.43 to 5.61, p = .50) and deep (RR 1.89, 95% CI 0.62 to 5.80) infections, arthritis symptoms (RR 1.20, 95% CI 0.92 to 1.58, p = .18), or chronic osteomyelitis (RR 0.31, 95% CI 0.05 to 1.84, p = .20) between the 2 groups. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  1. Mini-Fragment Fixation Is Equivalent to Bicortical Screw Fixation for Horizontal Medial Malleolus Fractures.

    Science.gov (United States)

    Wegner, Adam M; Wolinsky, Philip R; Robbins, Michael A; Garcia, Tanya C; Amanatullah, Derek F

    2018-05-01

    Horizontal fractures of the medial malleolus occur through application of valgus or abduction force through the ankle that creates a tension failure of the medial malleolus. The authors hypothesize that mini-fragment T-plates may offer improved fixation, but the optimal fixation construct for these fractures remains unclear. Forty synthetic distal tibiae with identical osteotomies were randomized into 4 fixation constructs: (1) two parallel unicortical cancellous screws; (2) two parallel bicortical cortical screws; (3) a contoured mini-fragment T-plate with 2 unicortical screws in the fragment and 2 bicortical screws in the shaft; and (4) a contoured mini-fragment T-plate with 2 bicortical screws in the fragment and 2 unicortical screws in the shaft. Specimens were subjected to offset axial tension loading on a servohydraulic testing system and tracked using high-resolution video. Failure was defined as 2 mm of articular displacement. Analysis of variance followed by a Tukey-Kramer post hoc test was used to assess for differences between groups, with significance defined as Pfragment T-plate constructs (239±83 N/mm and 190±37 N/mm) and the bicortical screw construct (240±17 N/mm) were not statistically different. The mean stiffness values of both mini-fragment T-plate constructs and the bicortical screw construct were higher than that of a parallel unicortical screw construct (102±20 N/mm). Contoured T-plate constructs provide stiffer initial fixation than a unicortical cancellous screw construct. The T-plate is biomechanically equivalent to a bicortical screw construct, but may be superior in capturing small fragments of bone. [Orthopedics. 2018; 41(3):e395-e399.]. Copyright 2018, SLACK Incorporated.

  2. Cadaveric aorta implantation for aortic graft infection.

    Science.gov (United States)

    Ali, Asad; Bahia, Sandeep S S; Ali, Tahir

    2016-01-01

    This case report describes a 73-year-old gentleman who underwent explantation of an infected prosthetic aorto-iliac graft and replacement with a cryopreserved thoracic and aorto-iliac allograft. The patient has been followed up a for more than a year after surgery and remains well. After elective tube graft repair of his abdominal aortic aneurysm (AAA) in 2003, he presented to our unit in 2012 in cardiac arrest as a result of a rupture of the distal graft suture line due to infection. After resuscitation he underwent aorto-bifemoral grafting using a cuff of the original aortic graft proximally. Distally the new graft was anastomosed to his common femoral arteries, with gentamicin beads left in situ. Post discharge the patient was kept under close surveillance with serial investigations including nuclear scanning, however it became apparent that his new graft was infected and that he would require aortic graft replacement, an operation with a mortality of at least 50%. The patient underwent the operation and findings confirmed a synthetic graft infection. This tube graft was explanted and a cryopreserved aorta was used to the refashion the abdominal aorta and its bifurcation. The operation required a return to theatre day one post operatively for a bleeding side branch, which was repaired. The patient went on to make a full recovery stepping down from the intensive therapy unit day 6 post operatively and went on to be discharged 32 days after his cryopreserved aorta implantation. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  3. Phase-Contrast Hounsfield Units of Fixated and Non-Fixated Soft-Tissue Samples

    Science.gov (United States)

    Willner, Marian; Fior, Gabriel; Marschner, Mathias; Birnbacher, Lorenz; Schock, Jonathan; Braun, Christian; Fingerle, Alexander A.; Noël, Peter B.; Rummeny, Ernst J.; Pfeiffer, Franz; Herzen, Julia

    2015-01-01

    X-ray phase-contrast imaging is a novel technology that achieves high soft-tissue contrast. Although its clinical impact is still under investigation, the technique may potentially improve clinical diagnostics. In conventional attenuation-based X-ray computed tomography, radiological diagnostics are quantified by Hounsfield units. Corresponding Hounsfield units for phase-contrast imaging have been recently introduced, enabling a setup-independent comparison and standardized interpretation of imaging results. Thus far, the experimental values of few tissue types have been reported; these values have been determined from fixated tissue samples. This study presents phase-contrast Hounsfield units for various types of non-fixated human soft tissues. A large variety of tissue specimens ranging from adipose, muscle and connective tissues to liver, kidney and pancreas tissues were imaged by a grating interferometer with a rotating-anode X-ray tube and a photon-counting detector. Furthermore, we investigated the effects of formalin fixation on the quantitative phase-contrast imaging results. PMID:26322638

  4. "Cold" Fixation: Reconciliation of Nitrogen Fixation Rates and Diazotroph Assemblages in the Arctic Ocean

    Science.gov (United States)

    Fong, A. A.; Waite, A.; Rost, B.; Richter, K. U.

    2016-02-01

    Measurements of biological nitrogen fixation are typically conducted in oligotrophic subtropical and tropical marine environments where concentrations of fixed inorganic nitrogen are low. To date, only a handful of nitrogen fixation studies have been conducted in high latitude marine environments, but further investigation is needed to resolve the distribution of cold ocean diazotrophic assemblages. Nitrogen fixation rates and nifH gene distributions were measured at seven stations from 5°E to 20°E, north of 81°N in the Arctic Ocean at the onset of summer 2015. Discrete water samples in ice-covered regions were collected from the sea surface to 200 m for 15N2-tracer additions and targeted nifH gene and transcript analyses. Previous work suggests that heterotrophic bacteria dominate diazotrophic communities in the Arctic Ocean. Therefore, additional nifH gene surveys of sinking particles were conducted to test for enrichment on organic matter-rich microenvironments. Together, these measurements aim to reconcile diazotrophic activity with microbial community composition, further elucidating how nitrogen fixers could impact current concepts in polar carbon and nutrient cycling.

  5. Decreasing Complications of Quadricepsplasty for Knee Contracture after Femoral Fracture Treatment with an External Fixator: Report of Four Cases

    Directory of Open Access Journals (Sweden)

    Naoya Kashiwagi

    2013-01-01

    Full Text Available Introduction: In performing quadricepsplasty for contracture that develops after application of an external fixator for femoral fractures, surgeons must be aware of the potential risk for re-fracture and pin-related problems. The purpose of this report is to highlight these not well-detailed complications and to discuss specific findings and treatment suggestions.Case Report: 4 men (mean age, 40 years presenting with secondary to contracture that developed after application of an external fixator for femoral fractures were included in this study. The radiographs showed union across the fracture site however two of these patients couldn't stand on one leg raising suspicion about the union status. A computed tomographic image indeed demonstrated limited continuity of the cortex. Bone grafting was performed prior to quadricepsplasty. The mean extension and flexion before the quadricepsplasty were 0o and 570 , respectively. At the final follow-up examination, the mean active flexion of the knee had increased to 98o.Results: The incidence of re-fracture during and after quadricepsplasty has been reported to be between 10 and 25%. There are 2 preoperative features that may mislead surgeons into believing that complete union of the fractures has been attained: one is the patient's ability to stand on a single leg, and the other is the fact that plain radiographs may lend themselves to different interpretations. In such cases, computed tomography will provide evidence of the continuity of the cortical bone. Bone grafting in 2 of our patients is thought to have prevented the postoperative complications of re-fracture. Complications at pin sites induce contracture at surrounding structures. When extreme tightness of the skin is noted, a tension-releasing procedure such as a skin graft should be performed.Conclusion: In conclusion, re-fracture or pin-site contracture should be carefully managed before quadricepsplasty, because the patients who need a

  6. Rehabilitation of Avulsed Teeth in Fractured Jaws via Bone Grafting and Implant Placement: Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Anshul Jain

    2016-01-01

    Full Text Available The maxillofacial region is one of the most injury-prone areas during road traffic accidents, personal violence, falls and sports. Maxillofacial trauma can lead to breakage or avulsion of upper anterior teeth, which may cause significant aesthetic and functional problems. There are many treatment options available for rehabilitation including removable partial dentures, fixed partial dentures, crown and bridges and implant-supported prostheses.Herein, two cases are presented where implant placement was done for upper anterior teeth, which were traumatized or avulsed following maxillofacial trauma. Both patients demonstrated a history of maxillofacial trauma and had undergone open reduction and internal fixation. The first patient had a severe maxillary alveolar defect treated via autogenous bone grafting and a six-month period was given for proper integration of the bone graft. The second patient was a smoker with very poor oral hygiene and a deep bite. Thus, implant placement was not initially justified.

  7. Two-Stage Surgical Management of Multilevel Symptomatic Thoracic Haemangioma Using Ethanol and Iliac Crest Bone Graft

    Science.gov (United States)

    Brahmajoshyula, Venkatramana; Mayi, Shivanand; Teegala, Suman

    2014-01-01

    This article presents a 56-year-old obese female who presented with back pain and progressive weakness in her lower limbs for three months. She was bed-ridden for one week before reporting to our hospital. Plain radiographs showed vertical striations in multiple vertebrae classical of haemangioma. Magnetic resonance imaging (MRI) spine revealed multiple thoracic and lumbar vertebral haemangiomas. Extra osseous extension of haemangioma at T12 was causing spinal cord compression. Two-stage surgery was performed with absolute alcohol (ethanol) injection followed by pedicle screw fixation and decompression with tricortical iliac crest bone graft into the vertebral body. Postoperatively rapid neurological improvement was seen. After three weeks, she could walk independently. One year later, computed tomography showed complete incorporation of bone graft and maintained vertebral body height. MRI showed complete resolution of the cord edema at T12. These findings indicated diminished vascularity of the tumor. PMID:25187869

  8. Imaging features of anterior cruciate ligament reconstruction graft insufficiency

    International Nuclear Information System (INIS)

    Shang Yao; Zhang Yue; Tian Chunyan; Zheng Zhuozhao

    2011-01-01

    Objective: To investigate the imaging features of anterior cruciate ligament (ACL) graft insufficiency. Methods: X-Ray and MR imaging examinations in 24 consecutive patients who had ACL reconstructive graft insufficiency were retrospectively evaluated for tunnel position, osteoarthrosis and its related complications. Follow-up arthroscopy showed 16 graft tears and 8 graft laxities. Fisher exact test was used to compare tunnel malpositions, the proportion of graft tear on MRI and osteoarthrosis between graft tear group and graft laxity group. Results: Two malpositions of tibial tunnel and 3 malpositions of femoral tunnel were seen in graft tear group. Three-malpositions of tibial tunnel and 4 malpositions of femoral tunnel were seen in graft laxity group. The proportion of tibial or femoral malposition showed no significant difference between the two groups (P=0.289, P=0.167). In graft tear group, 15 complete graft tears were diagnosed correctly, 1 partial tear was misdiagnosed as normal on MRI. In graft laxity group, 4 grafts were diagnosed as normal and 4 were considered as graft tear on MRI. A significant difference was seen between the two groups (P=0.028) in the proportion of graft tear diagnosed on MRI. Fourteen osteoarthrosis were seen in graft tear group and 5 in graft laxity group. No significant difference was seen between the two groups (P= 0.289) in the proportion of osteoarthrosis. Conclusion: The proportions of tunnel malposition and osteoarthrosis showed no significant difference between the graft tear group and graft Laxity group. Most graft tears can be diagnosed accurately on MRI, but some cases of graft laxity may be misdiagnosed for graft tear. (authors)

  9. Chloroanthraquinone as a grafted probe molecule to investigate grafting yield on carbon powder

    International Nuclear Information System (INIS)

    Le Comte, Annaïg; Brousse, Thierry; Bélanger, Daniel

    2016-01-01

    Spontaneous grafting of chloroanthraquinone (ClAQ) groups on Black Pearls carbon by reduction of the corresponding in-situ generated diazonium cations was successfully achieved. The presence of an halogen atom on the quinone molecule allowed the use of different spectroscopic characterization techniques to determine the accurate quinone content of the modified carbon. Electrochemical characterization highlighted that the presence of chlorine atom on the grafted molecule did not affect the electrochemical response or the grafting reaction efficiency. The amount of ClAQ molecules at the carbon surface after grafting was determined by cyclic voltammetry, together with thermogravimetric analysis coupled mass spectroscopy, X-ray photoelectron spectroscopy and elemental analysis. The ClAQ mass loadings estimated from the four techniques are in very good agreement and confirm that the grafted moieties are all electrochemically active and accessible. Finally, the grafting of quinone-type molecule using the reduction of diazonium cations does not affect the electroactivity of the grafted groups and cyclic voltammetry can be considered as a reliable technique to evaluate the mass loading of grafted quinone groups on porous carbon. Thus ClAQ can be used as a grafted probe molecule to investigate grafting yield on carbon powder, and this approach can be extended to functionalized electrodes used in an increasing number of electrochemical energy storage devices.

  10. Evaluation of synthetic vascular grafts in a mouse carotid grafting model.

    Directory of Open Access Journals (Sweden)

    Alex H P Chan

    Full Text Available Current animal models for the evaluation of synthetic grafts are lacking many of the molecular tools and transgenic studies available to other branches of biology. A mouse model of vascular grafting would allow for the study of molecular mechanisms of graft failure, including in the context of clinically relevant disease states. In this study, we comprehensively characterise a sutureless grafting model which facilitates the evaluation of synthetic grafts in the mouse carotid artery. Using conduits electrospun from polycaprolactone (PCL we show the gradual development of a significant neointima within 28 days, found to be greatest at the anastomoses. Histological analysis showed temporal increases in smooth muscle cell and collagen content within the neointima, demonstrating its maturation. Endothelialisation of the PCL grafts, assessed by scanning electron microscopy (SEM analysis and CD31 staining, was near complete within 28 days, together replicating two critical aspects of graft performance. To further demonstrate the potential of this mouse model, we used longitudinal non-invasive tracking of bone-marrow mononuclear cells from a transgenic mouse strain with a dual reporter construct encoding both luciferase and green fluorescent protein (GFP. This enabled characterisation of mononuclear cell homing and engraftment to PCL using bioluminescence imaging and histological staining over time (7, 14 and 28 days. We observed peak luminescence at 7 days post-graft implantation that persisted until sacrifice at 28 days. Collectively, we have established and characterised a high-throughput model of grafting that allows for the evaluation of key clinical drivers of graft performance.

  11. Evaluation of synthetic vascular grafts in a mouse carotid grafting model.

    Science.gov (United States)

    Chan, Alex H P; Tan, Richard P; Michael, Praveesuda L; Lee, Bob S L; Vanags, Laura Z; Ng, Martin K C; Bursill, Christina A; Wise, Steven G

    2017-01-01

    Current animal models for the evaluation of synthetic grafts are lacking many of the molecular tools and transgenic studies available to other branches of biology. A mouse model of vascular grafting would allow for the study of molecular mechanisms of graft failure, including in the context of clinically relevant disease states. In this study, we comprehensively characterise a sutureless grafting model which facilitates the evaluation of synthetic grafts in the mouse carotid artery. Using conduits electrospun from polycaprolactone (PCL) we show the gradual development of a significant neointima within 28 days, found to be greatest at the anastomoses. Histological analysis showed temporal increases in smooth muscle cell and collagen content within the neointima, demonstrating its maturation. Endothelialisation of the PCL grafts, assessed by scanning electron microscopy (SEM) analysis and CD31 staining, was near complete within 28 days, together replicating two critical aspects of graft performance. To further demonstrate the potential of this mouse model, we used longitudinal non-invasive tracking of bone-marrow mononuclear cells from a transgenic mouse strain with a dual reporter construct encoding both luciferase and green fluorescent protein (GFP). This enabled characterisation of mononuclear cell homing and engraftment to PCL using bioluminescence imaging and histological staining over time (7, 14 and 28 days). We observed peak luminescence at 7 days post-graft implantation that persisted until sacrifice at 28 days. Collectively, we have established and characterised a high-throughput model of grafting that allows for the evaluation of key clinical drivers of graft performance.

  12. Graft irradiation abrogates graft-versus-host disease in combined pancreas-spleen transplantation

    International Nuclear Information System (INIS)

    Schulak, J.A.; Sharp, W.J.

    1986-01-01

    A model of combined pancreas-spleen transplantation (PST) was studied in LBN F1 recipients of Lewis grafts in order to evaluate the efficacy of pretransplant graft irradiation in preventing lethal graft-versus-host disease (GVHD). Recipients of unmodified PST uniformly developed severe GVHD and died (MST = 16.7 +/- 3.8 days). Whole body donor irradiation with either 500 or 250 rad prevented lethal GVHD. Similarly, ex vivo graft irradiation with either 1000 or 500 rad also resulted in normal weight gain, graft function, and host survival for the 6-week study period. Conversely, delay of graft irradiation until 3 days after transplantation failed to prevent this complication (MST = 15.8 +/- 3.7 days). Recipients of irradiated grafts displayed glucose tolerance tests that were identical to those in the control group indicating that the doses of radiation employed in these experiments were not deleterious to islet function. Irradiated spleen grafts appeared histologically normal at 6 weeks after transplantation. Cells derived from these grafts failed to stimulate lymph node enlargement in a popliteal lymph node assay for GVHD, suggesting that these spleens may have become repopulated with host cells. These experiments confirm that PST has the potential to cause lethal GVHD and suggest that pretransplant graft irradiation may be used to prevent its occurrence

  13. Fracture healing using degradable magnesium fixation plates and screws.

    Science.gov (United States)

    Chaya, Amy; Yoshizawa, Sayuri; Verdelis, Kostas; Noorani, Sabrina; Costello, Bernard J; Sfeir, Charles

    2015-02-01

    Internal bone fixation devices made with permanent metals are associated with numerous long-term complications and may require removal. We hypothesized that fixation devices made with degradable magnesium alloys could provide an ideal combination of strength and degradation, facilitating fracture fixation and healing while eliminating the need for implant removal surgery. Fixation plates and screws were machined from 99.9% pure magnesium and compared with titanium devices in a rabbit ulnar fracture model. Magnesium device degradation and the effect on fracture healing and bone formation were assessed after 4 weeks. Fracture healing with magnesium device fixation was compared with that of titanium devices using qualitative histologic analysis and quantitative histomorphometry. Micro-computed tomography showed device degradation after 4 weeks in vivo. In addition, 2-dimensional micro-computed tomography slices and histologic staining showed that magnesium degradation did not inhibit fracture healing or bone formation. Histomorphology showed no difference in bone-bridging fractures fixed with magnesium and titanium devices. Interestingly, abundant new bone was formed around magnesium devices, suggesting a connection between magnesium degradation and bone formation. Our results show potential for magnesium fixation devices in a loaded fracture environment. Furthermore, these results suggest that magnesium fixation devices may enhance fracture healing by encouraging localized new bone formation. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  14. 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

  15. Adaptive significance of root grafting in trees

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.; Jones, R.

    1988-12-31

    Root grafting has long been observed in forest trees but the adaptive significance of this trait has not been fully explained. Various authors have proposed that root grafting between trees contributes to mechanical support by linking adjacent root systems. Keeley proposes that this trait would be of greatest advantage in swamps where soils provide poor mechanical support. He provides as evidence a greenhouse study of Nyssa sylvatica Marsh in which seedlings of swamp provenance formed between-individual root grafts more frequently than upland provenance seedlings. In agreement with this within-species study, Keeley observed that arid zone species rarely exhibit grafts. Keeley also demonstrated that vines graft less commonly than trees, and herbs never do. Since the need for mechanical support coincides with this trend, these data seem to support his model. In this paper, the authors explore the mechanisms and ecological significance of root grafting, leading to predictions of root grafting incidence. Some observations support and some contradict the mechanical support hypothesis.

  16. Autologous patch graft in tube shunt surgery.

    Science.gov (United States)

    Aslanides, I M; Spaeth, G L; Schmidt, C M; Lanzl, I M; Gandham, S B

    1999-10-01

    To evaluate an alternate method of covering the subconjunctival portion of the tube in aqueous shunt surgery. Evidence of tube erosion, graft-related infection, graft melting, or other associated intraocular complications were evaluated. A retrospective study of 16 patients (17 eyes) who underwent tube shunt surgery at Wills Eye Hospital between July 1991 and October 1996 was conducted. An autologous either "free" or "rotating" scleral lamellar graft was created to cover the subconjunctival portion of the tube shunt. All patients were evaluated for at least 6 months, with a mean follow-up of 14.8 months (range 6-62 months). All eyes tolerated the autologous graft well, with no clinical evidence of tube erosion, or graft-related or intraocular complications. Autologous patch graft in tube shunt surgery appears--in selected cases--to be an effective, safe and inexpensive surgical alternative to allogenic graft materials. It also offers ease of availability, and eliminates the risk of transmitting infectious disease.

  17. Radiation induced graft copolymerization of jute fibre

    International Nuclear Information System (INIS)

    Al-Siddique, F.R.; Khan, A.U.; Sheikh, R.A.

    1983-01-01

    Graft copolymerized jute fibres (GCJF) were prepared by γ-ray induced graft copolymerization of various monomers onto bleached and de-waxed jute samples. The effect of γ-ray dose on the tendency of various monomers to form graft co-polymer was studied. It was found that the tendency decreases as follows: methylmethacrylate (MMA)>acrylonitrile (AN)>styrene (STY)>vinylacetate (VA). When the effect of monomer concentration on the formation of graft co-polymer was studied, it was found that a mixture of AN and STY gave a higher amount of grafting than what was observed for STY or AN alone, when used at a comparable concentration. A study on the effect of concentration of methyl alcohol (a swelling agent for jute) on the tendency of the monomers to form graft co-polymer showed that although there is no effect when only AN is used, an appreciable effect is observed if AN is mixed with STY. In the later case the tendency of graft co-polymerization increases with the increase of CH 3 OH concentration. It was further observed that the increase of CH 3 OH also has a positive influence on MMA to form graft co-polymer in the range of 40-90% CH 3 OH. The affinity of GCJF towards moisture has been found to decrease with the increase of polymer loading onto jute. The presence of swelling agents during graft copolymer formation was also found to decrease the affinity of GCJF towards moisture. (author)

  18. Early Experience with Biodegradable Fixation of Pediatric Mandibular Fractures

    OpenAIRE

    Mazeed, Ahmed Salah; Shoeib, Mohammed Abdel-Raheem; Saied, Samia Mohammed Ahmed; Elsherbiny, Ahmed

    2014-01-01

    This clinical study aims to evaluate the stability and efficiency of biodegradable self-reinforced poly-l/dl-lactide (SR-PLDLA) plates and screws for fixation of pediatric mandibular fractures. The study included 12 patients (3–12 years old) with 14 mandibular fractures. They were treated by open reduction and internal fixation by SR-PLDLA plates and screws. Maxillomandibular fixation was maintained for 1 week postoperatively. Clinical follow-up was performed at 1 week, 6 weeks, 3 months, and...

  19. Operative Fixation Options for Elective and Diabetic Ankle Arthrodesis.

    Science.gov (United States)

    Ramanujam, Crystal L; Stapleton, John J; Zgonis, Thomas

    2017-07-01

    Ankle arthrodesis remains one of the most definitive treatment options for end-stage arthritis, paralysis, posttraumatic and postinfectious conditions, failed total ankle arthroplasty, and severe deformities. The general aims of ankle arthrodesis are to decrease pain and instability, correct the accompanying deformity, and create a stable plantigrade foot. Several surgical approaches have been reported for ankle arthrodesis with internal fixation options. External fixation has also evolved for ankle arthrodesis in certain clinical scenarios. This article provides a comprehensive analysis of midterm to long-term outcomes for ankle arthrodesis using internal and/or external fixation each for elective and diabetic conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Carbon Dioxide Fixation in Isolated Kalanchoe Chloroplasts 1

    Science.gov (United States)

    Levi, Carolyn; Gibbs, Martin

    1975-01-01

    Chloroplasts isolated from Kalanchoe diagremontiana leaves were capable of photosynthesizing at a rate of 5.4 μmoles of CO2 per milligram of chlorophyll per hour. The dark rate of fixation was about 1% of the light rate. A high photosynthetic rate was associated with low starch content of the leaves. Ribose 5-phosphate, fructose 1,6-diphosphate, and dithiothreitol stimulated fixation, whereas phosphoenolpyruvate and azide were inhibitors. The products of CO2 fixation were primarily those of the photosynthetic carbon reduction cycle. PMID:16659249

  1. Transpedicular hydroxyapatite grafting with indirect reduction for thoracolumbar burst fractures with neurological deficit: A prospective study

    Directory of Open Access Journals (Sweden)

    Toyone Tomoaki

    2007-01-01

    Full Text Available Background: The major problem after posterior correction and instrumentation in the treatment of thoracolumbar burst fractures is failure to support the anterior spinal column leading to loss of correction of kyphosis and hardware breakage. We conducted a prospective consecutive series to evaluate the outcome of the management of acute thoracolumbar burst fractures by transpedicular hydroxyapatite (HA grafting following indirect reduction and pedicle screw fixation. Materials and Methods: Eighteen consecutive patients who had thoracolumbar burst fractures and associated incomplete neurological deficit, operatively treated within four days of admission. Following indirect reduction and pedicle screw fixation, transpedicular intracorporeal HA grafting to the fractured vertebrae was performed. Mean operative time was 125 min and mean blood loss was 150 ml. Their implants were removed within one year and were prospectively followed for at least two years. Results: The neurological function of all 18 patients improved by at least one ASIA grade, with nine (50% patients demonstrating complete neurological recovery. Sagittal alignment was improved from a mean preoperative kyphosis of 17°to -2°(lordosis by operation, but was found to have slightly deteriorated to 1° at final follow-up observation. The CT images demonstrated a mean spinal canal narrowing pre-operatively immediate post-operative and at final followup of 60%, 22% and 11%, respectively . There were no instances of hardware failure. No patient reported severe pain or needed daily dosages of analgesics at the final follow-up. The two-year postoperative MRI demonstrated an increase of one grade in disc degeneration (n = 17 at the disc above and in 11 patients below the fractured vertebra. At the final follow-up, flexion-extension radiographs revealed that a median range of motion was 4, 6 and 34 degrees at the cranial segment of the fractured vertebra, caudal segment and L1-S1, respectively

  2. Biomechanical evaluation of the impact of various facet joint lesions on the primary stability of anterior plate fixation in cervical dislocation injuries: a cadaver study: Laboratory investigation.

    Science.gov (United States)

    Oberkircher, Ludwig; Born, Sebastian; Struewer, Johannes; Bliemel, Christopher; Buecking, Benjamin; Wack, Christina; Bergmann, Martin; Ruchholtz, Steffen; Krüger, Antonio

    2014-10-01

    Injuries of the subaxial cervical spine including facet joints and posterior ligaments are common. Potential surgical treatments consist of anterior, posterior, or anterior-posterior fixation. Because each approach has its advantages and disadvantages, the best treatment is debated. This biomechanical cadaver study compared the effect of different facet joint injuries on primary stability following anterior plate fixation. Fractures and plate fixation were performed on 15 fresh-frozen intact cervical spines (C3-T1). To simulate a translation-rotation injury in all groups, complete ligament rupture and facet dislocation were simulated by dissecting the entire posterior and anterior ligament complex between C-4 and C-5. In the first group, the facet joints were left intact. In the second group, one facet joint between C-4 and C-5 was removed and the other side was left intact. In the third group, both facet joints between C-4 and C-5 were removed. The authors next performed single-level anterior discectomy and interbody grafting using bone material from the respective thoracic vertebral bodies. An anterior cervical locking plate was used for fixation. Continuous loading was performed using a servohydraulic test bench at 2 N/sec. The mean load failure was measured when the implant failed. In the group in which both facet joints were intact, the mean load failure was 174.6 ± 46.93 N. The mean load failure in the second group where only one facet joint was removed was 127.8 ± 22.83 N. In the group in which both facet joints were removed, the mean load failure was 73.42 ± 32.51 N. There was a significant difference between the first group (both facet joints intact) and the third group (both facet joints removed) (p cadaver study, primary stability of anterior plate fixation for dislocation injuries of the subaxial cervical spine was dependent on the presence of the facet joints. If the bone in one or both facet joints is damaged in the clinical setting, anterior plate

  3. Acrylique acid grafted polyolefines. Thermoadhesive applications

    International Nuclear Information System (INIS)

    Guimon, Claude

    1979-01-01

    Radiochemical grafting of polyolefines by peroxidation has been industrialized in France for about 10 years by irradiation of these polymers with an electron accelerator and then treated by acrylic acid. Products obtained show a high adhesivity on metallic surfaces above their melting point. The main application of acrylic acid grafted high density polyethylene is composite film with aluminum foil for thermosealing of plastic bottle caps of sterilized milk. Acrylic acid grafted polypropylene is used in suspension in a volatile liquid for aluminum foil coating satisfying food packaging regulations [fr

  4. Grafting heterogeneous catalyst with gamma radiation

    International Nuclear Information System (INIS)

    Garnett, J.L.; Long, M.A.; Levot, R.G.

    1984-01-01

    A process for the production of a heterogeneous catalyst comprises the steps of: irradiating an organic macromolecular substrate or a metal substrate with ionising or ultra violet radiation in the presence of a monomer selected from the group consisting of o-, m-, or p- styryl diphenyl phosphine and o-, m- or p- phenyl acrylyl diphenyl phosphine, to graft the monomer to the substrate; and reacting the graft copolymer with a homogeneous catalyst selected from the group consisting of catalytic metal salts and catalytic organometallic complexes such that the graft copolymer conjugate becomes a ligand of the catalyst

  5. 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

  6. 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.

  7. Bone Graft Substitutes : Developed for Trauma and Orthopaedic Surgery

    NARCIS (Netherlands)

    J. van der Stok (Johan)

    2015-01-01

    markdownabstract__Abstract__ Bone grafting was established in the 19th century and has become a common procedure in which bone defects are filled with bone grafts or bone graft substitutes. Bone defects that require bone grafting are encountered in approximately 10% of trauma and orthopaedic

  8. Hot callusing for propagation of American beech by grafting

    Science.gov (United States)

    David W. Carey; Mary E. Mason; Paul Bloese; Jennifer L. Koch

    2013-01-01

    To increase grafting success rate, a hot callus grafting system was designed and implemented as part of a multiagency collaborative project to manage beech bark disease (BBD) through the establishment of regional BBD-resistant grafted seed orchards. Five years of data from over 2000 hot callus graft attempts were analyzed using a logistic regression model to determine...

  9. Bridging Graft in Irreparable Massive Rotator Cuff Tears: Autogenic Biceps Graft versus Allogenic Dermal Patch Graft.

    Science.gov (United States)

    Rhee, Sung Min; Oh, Joo Han

    2017-12-01

    Few comparative studies have reported on the use of biologic grafts for irreparable massive rotator cuff tears. The purpose of this study was to assess the results of arthroscopic bridging graft in irreparable massive rotator cuff tears using an autogenic long head of biceps tendon (LHBT) or an allogenic dermal patch (ADP). We retrospectively reviewed 24 patients treated using the LHBT (group I) and eight patients with complete rupture of the LHBT treated using an ADP (group II) since 2011. Preoperative Goutallier's fatty degeneration, range of motion (ROM), visual analogue scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES) score, and Quick Disabilities of the Arm, Shoulder, and Hand (DASH) score were assessed and healing failure was evaluated at 1 year after surgery by ultrasonography or magnetic resonance imaging. The mean fatty degeneration in groups I and II was 3.9 and 3.6 for the supraspinatus ( p = 0.288), 2.7 and 2.9 for the infraspinatus ( p = 0.685), 0.9 and 1.3 for the subscapularis ( p = 0.314), and 1.3 and 3.0 for the teres minor ( p = 0.005), respectively. Subscapularis tears were found in 8 patients (33.3%) in group I and in 7 patients (87.5%) in group II ( p = 0.023). Mean ROMs and functional scores improved significantly in group I (forward flexion: 121.7° to 153.3°, p = 0.010; external rotation: 32.7° to 52.7°, p = 0.001; external rotation at 90°: 63.3° to 74.5°, p = 0.031; internal rotation: T10.5 to T9.3, p = 0.045; VAS: 7.0 to 1.1, p rotator cuff tears, especially in patients with severe fatty degeneration in the teres minor or combined biceps and subscapularis tears.

  10. Feasibility of the Use of RapiGraft and Skin Grafting in Reconstructive Surgery

    Directory of Open Access Journals (Sweden)

    Jung Dug Yang

    2016-09-01

    Full Text Available BackgroundSkin grafting is a relatively simple and thus widely used procedure. However, the elastic and structural quality of grafted skin is poor. Recently, various dermal substitutes have been developed to overcome this disadvantage of split-thickness skin grafts. The present study aims to determine the feasibility of RapiGraft as a new dermal substitute.MethodsThis prospective study included 20 patients with partial- or full-thickness skin defects; the patients were enrolled between January 2013 and March 2014. After skin defect debridement, the wound was divided into two parts by an imaginary line. Split-thickness skin grafting alone was performed on one side (group A, and RapiGraft and split-thickness skin grafting were used on the other side (group B. All patients were evaluated using photographs and self-questionnaires. The Manchester scar scale (MSS, a chromameter, and a durometer were used for the scar evaluation. The average follow-up period was 6 months.ResultsThe skin graft take rates were 93% in group A and 89% in group B, a non-significant difference (P=0.082. Statistically, group B had significantly lower MSS, vascularity, and pigmentation results than group A (P<0.05 for all. However, the groups did not differ significantly in pliability (P=0.155.ConclusionsThe present study indicates that a simultaneous application of RapiGraft and a split-thickness skin graft is safe and yields improved results. Therefore, we conclude that the use of RapiGraft along with skin grafting will be beneficial for patients requiring reconstructive surgery.

  11. Delayed grafting for banked skin graft in lymph node flap transfer.

    Science.gov (United States)

    Ciudad, Pedro; Date, Shivprasad; Orfaniotis, Georgios; Dower, Rory; Nicoli, Fabio; Maruccia, Michele; Lin, Shu-Ping; Chuang, Chu-Yi; Chuang, Tsan-Yu; Wang, Gou-Jen; Chen, Hung-Chi

    2017-02-01

    Over the last decade, lymph node flap (LNF) transfer has turned out to be an effective method in the management of lymphoedema of extremities. Most of the time, the pockets created for LNF cannot be closed primarily and need to be resurfaced with split thickness skin grafts. Partial graft loss was frequently noted in these cases. The need to prevent graft loss on these iatrogenic wounds made us explore the possibility of attempting delayed skin grafting. We have herein reported our experience with delayed grafting with autologous banked split skin grafts in cases of LNF transfer for lymphoedema of the extremities. Ten patients with International Society of Lymphology stage II-III lymphoedema of upper or lower extremity were included in this study over an 8-month period. All patients were thoroughly evaluated and subjected to lymph node flap transfer. The split skin graft was harvested and banked at the donor site, avoiding immediate resurfacing over the flap. The same was carried out in an aseptic manner as a bedside procedure after confirming flap viability and allowing flap swelling to subside. Patients were followed up to evaluate long-term outcomes. Flap survival was 100%. Successful delayed skin grafting was done between the 4th and 6th post-operative day as a bedside procedure under local anaesthesia. The split thickness skin grafts (STSG) takes more than 97%. One patient needed additional medications during the bedside procedure. All patients had minimal post-operative pain and skin graft requirement. The patients were also reported to be satisfied with the final aesthetic results. There were no complications related to either the skin grafts or donor sites during the entire period of follow-up. Delayed split skin grafting is a reliable method of resurfacing lymph node flaps and has been shown to reduce the possibility of flap complications as well as the operative time and costs. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  12. Preparation of poly(vinylbenzyl chloride)-grafted PFA film by a simultaneous irradiation grafting method

    International Nuclear Information System (INIS)

    Fei, Geng; Shin, Jun Hwa; Nho, Young Chang; Lee, Youn Sik

    2009-01-01

    In this study, PFA-g-PVBC films were prepared by a radiation grafting of vinylbenzyl chloride (VBC) monomer onto poly(tetrafluoroethylene-co-perfluoro propyl vinyl ether) (PFA) films by simultaneous irradiation method. IR, TGA, and SEM-EDX instruments were utilized to confirm the successful preparation of the grafted film. The effects of several irradiation conditions, including the dose, VBC concentration, and film thickness on the degree of grafting of PFA-g-PVBC film were investigated

  13. Determination of the distribution of graft yields following a radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Schipschack, K.; Wagner, H.; Sawtschenko, L.

    1976-01-01

    In the radiation-induced graft copolymerization on solid initial polymers a distribution of graft yields takes place along the cross-sections of samples. Methods for determining this distribution, which are described in the literature, are reviewed. In our own investigations boards made of ethylene-vinyl acetate copolymers and grafted with vinyl chloride were used. Distributions of the grafted component obtained by infrared analysis of microtome cuts parallel to the surface are partly rather inhomogeneous, and are interpreted as dependent on the experimental parameters. (author)

  14. Necrotizing fasciitis after internal fixation of fracture of femoral trochanteric ? ??

    OpenAIRE

    Santos, Leandro Em?lio Nascimento; Pires, Robinson Esteves Santos; Figueiredo, Leonardo Brand?o; Soares, Eduardo Augusto Marques

    2014-01-01

    Necrotizing fasciitis is a rare and potentially lethal soft tissue infection. We report a case of trochanteric femur fracture in a patient who underwent fracture fixation and developed necrotizing fasciitis. A literature review on the topic will be addressed.

  15. Use of 15N methodology to assess biological nitrogen fixation

    International Nuclear Information System (INIS)

    Hardarson, G.

    1990-01-01

    One of the most important characteristics of legumes are their ability in symbiosis with Rhizobium bacteria to fix atmospheric nitrogen for growth. For proper management and a full realization of the benefits of this plant-microbial association, it is necessary to estimate how much nitrogen is fixed under different conditions in the field. It is only after this is known that various factors can be manipulated so as to increase the amount and proportion of N a plant derives from biological fixation. A suitable method for accurately measuring the amount of N crops derive from fixation is therefore an important requirement in any programme aimed at maximizing biological nitrogen fixation. There are several methods available to measure N 2 fixation (Bergersen, 1980) based on (1) increment in N yield and plant growth, (2) nitrogen balance (3) acetylene reduction and (4) the use of isotopes of N. Only isotopic methods will be illustrated here. 20 refs, 2 figs, 9 tabs

  16. Outcome of complex tibial plateau fractures treated with external fixator

    Directory of Open Access Journals (Sweden)

    Sushil H Mankar

    2012-01-01

    Conclusion: We believe that minimally invasive treatment by percutaneous techniques and external fixation is a fairly reasonable treatment alternative, if near anatomical reduction of joint surface can be confirmed on fluoroscopy.

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

    African Journals Online (AJOL)

    hole Y plates with monocortical screws. 150 N incisal occlusal loads were simulated on the models. The commercial ANSYS software was utilized to calculate the Von Mises stresses on fixative appliances. Results: The highest Von Mises stress ...

  18. Cyanobacteria Occurrence and Nitrogen Fixation Rates in the ...

    African Journals Online (AJOL)

    Keywords: Cyanobacteria, Nitrogen Fixation, Seagrass, Seaweed Farming. Abstract—The .... during every sampling period, using a mercury thermometer and a ..... Capone, D.G. (1993) Determination of nitrogenase activity in aquatic samples ...

  19. 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)

  20. Nitrogen fixation rates in the eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Ahmed, A.; Gauns, M.; Kurian, S.; Bardhan, P.; Pratihary, A.K.; Naik, H.; Shenoy, D.M.; Naqvi, S.W.A.

    The Arabian Sea experiences bloom of the diazotroph Trichodesmium during certain times of the year when optimal sea surface temperature and oligotrophic condition favour their growth. We measured nitrogen fixation rates in the euphotic zone during...

  1. Symbiotic N fixation of several soybean varieties and mutants

    International Nuclear Information System (INIS)

    Soertini, G.; Hendratno

    1988-01-01

    Symbiotic N fixation of several soybean varieties and mutants. Research activities comprising of three experiments were carried out to screen several soybean varieties and mutants for symbiotic N fixation potential. The first two experiments involved screening of seven rhizobium strains/isolate for effective N fixation. Depending on the medium used, plant response to strains was different. In sterile medium, rhizobium strain USDA 136, 142 and TAL 102 showed a high nitrogen fixation potential. In soil only rhizobium strain USDA 110 had better performance and proved to be competitive to the native strains. Nitrogen-15 dilution method was used to screen nitrogen fixing ability of several soybean varieties and mutants. Guntur variety showed a better response to high dose of N fertilizer without disturbance in its fixing ability. This variety then was considered good to be introduced in the cropping system. (author). 8 refs

  2. Fixation of tritium in a highly stable polymer form

    International Nuclear Information System (INIS)

    Steinberg, M.; Colombo, P.; Pruzansky, J.

    1977-01-01

    A method for the fixation of tritium comprises reacting tritiated water with calcium carbide to produce calcium hydroxide and tritiated acetylene, polymerizing the acetylene, and then incorporating the polymer in a solidifying matrix. 2 claims

  3. Improving food and agricultural production. Thailand. Biological nitrogen fixation

    International Nuclear Information System (INIS)

    Bowen, G.D.

    1991-01-01

    The aim of the mission was to assist the counterpart scientists in the analysis and interpretation of data relating to nitrogen fixation studies on grain legumes. The report briefly summarizes the discussions that were held with the counterparts

  4. Enrichment of autologous fat grafts with ex-vivo expanded adipose tissue-derived stem cells for graft survival

    DEFF Research Database (Denmark)

    Kølle, Stig-Frederik Trojahn; Fischer-Nielsen, Anne; Mathiasen, Anders Bruun

    2013-01-01

    Autologous fat grafting is increasingly used in reconstructive surgery. However, resorption rates ranging from 25% to 80% have been reported. Therefore, methods to increase graft viability are needed. Here, we report the results of a triple-blind, placebo-controlled trial to compare the survival ...... of fat grafts enriched with autologous adipose-derived stem cells (ASCs) versus non-enriched fat grafts....

  5. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    Directory of Open Access Journals (Sweden)

    Ying Guan

    2016-08-01

    Full Text Available Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU and polyester graft (nitinol-PET materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft.

  6. Temporary occipital fixation in young children with severe cervical-thoracic spinal deformity.

    Science.gov (United States)

    Kelley, Brian J; Minkara, Anas A; Angevine, Peter D; Vitale, Michael G; Lenke, Lawrence G; Anderson, Richard C E

    2017-10-01

    OBJECTIVE The long-term effects of instrumentation and fusion of the occipital-cervical-thoracic spine on spinal growth in young children are poorly understood. To mitigate the effects of this surgery on the growing pediatric spine, the authors report a novel technique used in 4 children with severe cervical-thoracic instability. These patients underwent instrumentation from the occiput to the upper thoracic region for stabilization, but without bone graft at the craniovertebral junction (CVJ). Subsequent surgery was then performed to remove the occipital instrumentation, thereby allowing further growth and increased motion across the CVJ. METHODS Three very young children (15, 30, and 30 months old) underwent occipital to thoracic posterior segmental instrumentation due to cervical or upper thoracic dislocation, progressive kyphosis, and myelopathy. The fourth child (10 years old) underwent similar instrumentation for progressive cervical-thoracic scoliosis. Bone graft was placed at and distal to C-2 only. After follow-up CT scans demonstrated posterior arthrodesis without unintended fusion from the occiput to C-2, 3 patients underwent removal of the occipital instrumentation. RESULTS Follow-up cervical spine flexion/extension radiographs demonstrated partial restoration of motion at the CVJ. One patient has not had the occipital instrumentation removed yet, because only 4 months have elapsed since her operation. CONCLUSIONS Temporary fixation to the occiput provides increased biomechanical stability for spinal stabilization in young children, without permanently eliminating motion and growth at the CVJ. This technique can be considered in children who require longer instrumentation constructs for temporary stabilization, but who only need fusion in more limited areas where spinal instability exists.

  7. An Introduction to the Septal Extension Graft

    Directory of Open Access Journals (Sweden)

    Myung-Hoon Kim

    2014-01-01

    Full Text Available The septal extension graft is a very useful method of controlling nasal lengthening and tip projection, rotation, and shape by fixing a graft to the septum, which leads to a strong supporting structure. Enhancing graft stability is important for better long-term outcomes and minimizing complications or relapse, and even more efficient application of these methods is needed for East Asians who lack enough cartilage to be harvested in addition to possessing a weak cartilage framework. In this paper, the methods for overcoming the drawbacks of the septal extension graft, such as instability, a fixed tip, and insufficiency of cartilage, are presented, and the applications of each method for greater satisfaction with surgical outcomes are also discussed.

  8. Radiation-induced grafting onto wool

    International Nuclear Information System (INIS)

    Muller-Schulte, D.

    1979-10-01

    Radiation-induced grafting tests were done on single wool fibres. Different vinyl monomers were used for this purpose and they were grafted in twenty different solvents which were selected for their swelling effiency and solvent parameters. The tests were done once with and once without the addition of water. The presence of water causes the polymer uptake to increase considerably. Formic acid/methanol and methanol were found to be the most suitable solvent systems, as they have the highest hydrogen-bond interaction effiency. The moisture uptake of wool depends on the hydrophily and hydrophoby of the grafted polymers. The single-fibre tests serve as a basis for analogous grafting tests on wool fabrics. The permanent- press was improved by graftng with hydrophoric polymers and polymers with a high glass-transition temperature [af

  9. The Role of Personality and Team-Based Product Dissection on Fixation Effects

    Science.gov (United States)

    Toh, Christine; Miller, Scarlett; Kremer, Gül E. Okudan

    2013-01-01

    Design fixation has been found to be complex in its definition and expression, but it plays an important role in design idea generation. Identifying the factors that influence fixation is crucial in understanding how to enhance the design process and reduce the negative effects of fixation. One way to potentially mitigate fixation is through…

  10. Pinch grafting for chronic venous leg ulcers in general practice

    OpenAIRE

    Steele, Keith

    1985-01-01

    Twenty-five patients with chronic venous leg ulcers were treated in general practice by pinch grafting. Fifteen of the ulcers (60%) were completely healed one year after grafting. Prior to grafting 19 patients (76%) complained of daily pain in the ulcer. These patients experienced complete relief from pain after grafting. Pinch grafting is a simple, safe and effective therapy when applied in a domiciliary environment.

  11. Nitrogen supply of crops by biological nitrogen fixation. 2

    International Nuclear Information System (INIS)

    Jensen, E.S.; Andersen, A.J.; Soerensen, H.; Thomsen, J.D.

    1985-02-01

    In the present work the contributions from combined N-sources and symbiotic nitrogen fixation to the nitrogen supply of field-grown peas and field beans were evaluated by means of 15 N fertilizer dilution. The effect of N-fertilizer, supplied at sowing and at different stages of plant development, on nitrogen fixation, yield and protein production in peas, was studied in pot experiments. (author)

  12. A Novel Handmade External Fixator for Phalangeal and Metacarpal Fractures

    Directory of Open Access Journals (Sweden)

    Davod Jafari

    2016-12-01

    Full Text Available Background The value of external fixation in complex hand injuries is well established. Expenses and technical difficulties of commercial mini external fixator sets have led to the innovation of handmade external fixators. These fixators are used as versatile facilities to treat certain hand fractures. Usually, these structures are made by k-wires crossed filled with cement plastic tube. However, these fixators have multiple deficiencies that should be addressed. Objectives In this study, we described in detail the surgical technique of a handmade concrete like mini external fixator and report its clinical use and results. Methods Our handmade external fixator was applied for 52 patients with 56 fractures. Only 5% of the fractures were closed, non-comminuted extra-articular, and the other 51 fractures were more complex injuries. The mean follow up time was 9.3 months. At the end of the follow up, radiologic and functional assessment (DASH: Disability of arm, shoulder and hand and TAM: Total active motion was evaluated. Results All 56 fractures were united completely. None of the cases experienced pin loosening or reduction loss. Of the fractures, 8.9% malunited due to fracture complexity. The mean dash score was 3.76. TAM was excellent in 45% of the fractures; it was good in 7% and fair in 4%. Conclusions This type of handmade external fixator is simple, lightweight, and cheap. Furthermore, all implements are readily available in most operating fields. The probability of loosening has been greatly diminished because of the concrete like structure. Easy and fast assembly and good clinical and functional results are the other advantages of this technique. Due to the less complication and benefits, this technique could be used for many phalangeal and metacarpal fractures with confidence.

  13. Postinflammatory ossicular fixation: CT analysis with surgical correlation

    International Nuclear Information System (INIS)

    Swartz, J.D.; Wolfson, R.J.; Marlowe, F.I.; Popky, G.L.

    1985-01-01

    Postinflammatory ossicular fixation is a common problem encountered by the otologic surgeon upon exploration because of conductive hearing loss in patients with chronic otitis media. These nonotosclerotic noncongenital lesions take three pathologic forms: fibrous tissue fixation (chronic adhesive otitis media), hyalinization of collagen (tympanosclerosis), and new bone formation (fibro-osseous sclerosis). More than 300 patients with the clinical diagnosis of chronic otitis media have been examined. This study encompasses 23 proved cases

  14. Bilateral spontaneous subluxation of scleral-fixated intraocular lenses.

    Science.gov (United States)

    Assia, Ehud I; Nemet, Arie; Sachs, Dani

    2002-12-01

    Two young men with primary ectopic lenses had intracapsular cataract extraction and scleral fixation of posterior chamber intraocular lenses (PC IOLs) using 10-0 polypropylene sutures tied to the IOL eyelets. Three to 9 years after implantation, spontaneous IOL vertical subluxation occurred in all 4 eyes (5 IOL loops), probably because of suture breakage. Late subluxation of a sutured IOL may occur several years after implantation. Double fixation and thicker sutures should be considered, especially in young patients.

  15. Strategies to improve macroencapsulated islet graft survival

    OpenAIRE

    Sörenby, Anne

    2007-01-01

    Chronic immunosuppressive therapy may have severe side-effects. In cell transplantation, the graft can be encapsulated within a membrane chamber, providing a physical barrier against the immune system. The cell graft then becomes dependent on the diffusion of nutrients and oxygen from the surrounding microcirculation. A major drawback has been the formation of avascular fibrotic tissue around the chamber. The immunoprotective device studied (TheraCyte ) has an outer membrane...

  16. Induced membrane technique combined with two-stage internal fixation for the treatment of tibial osteomyelitis defects.

    Science.gov (United States)

    Luo, Fei; Wang, Xiaohua; Wang, Shulin; Fu, Jingshu; Xie, Zhao

    2017-07-01

    The purpose of this study was to observe the effects of induced membrane technique combined with two-stage internal fixation in the treatment of tibial osteomyelitis defects. A retrospective analyses for 67 cases of tibialosteomyelitis defects were admitted to our department between September 2012 to February 2015, which were treated with induced membrane technique. At the first stage, implanted with a PMMA cement spacer in the defects after radical debridement and fixed with reconstructive locked plate. Bone grafting and exchanged the plate with intramedullary nail at the second stage. In current study, all patients were followed up for 18-35 months. Sixty-six patients achieved bone union with the average radiographic and clinical healing times of 5.55±2.19 and 7.45±1.69months, respectively. Seven patients required a second debridement before grafting, while four patients experienced a recurrence of infection or a relapse following second stage treatment. Twelve patients experienced either knee or ankle dysfunctions and 2 patients faced delayed wound healing. Donor site complications includes pain and infection were found in 7 and 3 patients, respectively with delayed stress fracture in 1 patient only. Induced membrane technique for the treatment of tibial osteomyelitis defects, seems a reliable method. The use of reconstructive locked plate as a temporary internal fixation at the first stage and exchanged with intramedullary nail at the second stage, potentially achieves good clinical efficacy. Care should be taken to restore the joint function especially in distal tibia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Fatal outcome after insufficient spine fixation for pyogenic thoracic spondylodiscitis: an imperative for 360° fusion of the infected spine

    Directory of Open Access Journals (Sweden)

    Moore Ernest E

    2009-02-01

    Full Text Available Abstract Background Pyogenic spondylodiscitis represents a potentially life-threatening condition. Due to the low incidence, evidence-based surgical recommendations in the literature are equivocal, and the treatment modalities remain controversial. Case presentation A 59 year-old patient presented with a history of thoracic spondylodiscitis resistant to antibiotic treatment for 6 weeks, progressive severe back pain, and a new onset of bilateral lower extremity weakness. Clinically, the patient showed a deteriorating spastic paraparesis of her lower extremities. An emergent MRI revealed a kyphotic wedge compression fracture at T7/T8 with significant spinal cord compression, paravertebral and epidural abscess, and signs of myelopathy. The patient underwent surgical debridement with stabilization of the anterior column from T6–T9 using an expandable titanium cage, autologous bone graft, and an anterolateral locking plate. The patient recovered well under adjunctive antibiotic treatment. She presented again to the emergency department 6 months later, secondary to a repeat fall, with acute paraplegia of the lower extremities and radiographic evidence of failure of fixation of the anterior T-spine. She underwent antero-posterior revision fixation with hardware removal, correction of kyphotic malunion, evacuation of a recurrent epidural abscess, decompression of the spinal canal, and 360° fusion from T2–T11. Despite the successful salvage procedure, the patient deteriorated in the postoperative phase, when she developed multiple complications including pneumonia, acute respiratory distress syndrome, bacterial meningitis, abdominal compartment syndrome, followed by septic shock with multiple organ failure and a lethal outcome within two weeks after revision surgery. Conclusion This catastrophic example of a lethal outcome secondary to failure of anterior column fixation for pyogenic thoracic spondylodiscitis underlines the notion that surgical

  18. Plant densities and modulation of symbiotic nitrogen fixation in soybean

    Directory of Open Access Journals (Sweden)

    Marcos Javier de Luca

    2014-06-01

    Full Text Available Soybean nitrogen (N demands can be supplied to a large extent via biological nitrogen fixation, but the mechanisms of source/sink regulating photosynthesis/nitrogen fixation in high yielding cultivars and current crop management arrangements need to be investigated. We investigated the modulation of symbiotic nitrogen fixation in soybean [Glycine max (L. Merrill] at different plant densities. A field trial was performed in southern Brazil with six treatments, including non-inoculated controls without and with N-fertilizer, both at a density of 320,000 plants ha−1, and plants inoculated with Bradyrhizobium elkanii at four densities, ranging from 40,000 to 320,000 plants ha−1. Differences in nodulation, biomass production, N accumulation and partition were observed at stage R5, but not at stage V4, indicating that quantitative and qualitative factors (such as sunlight infrared/red ratio assume increasing importance during the later stages of plant growth. Decreases in density in the inoculated treatments stimulated photosynthesis and nitrogen fixation per plant. Similar yields were obtained at the different plant densities, with decreases only at the very low density level of 40,000 plants ha−1, which was also the only treatment to show differences in seed protein and oil contents. Results confirm a fine tuning of the mechanisms of source/sink, photosynthesis/nitrogen fixation under lower plant densities. Higher photosynthesis and nitrogen fixation rates are capable of sustaining increased plant growth.

  19. Effects of tissue fixation and dehydration on tendon collagen nanostructure.

    Science.gov (United States)

    Turunen, Mikael J; Khayyeri, Hanifeh; Guizar-Sicairos, Manuel; Isaksson, Hanna

    2017-09-01

    Collagen is the most prominent protein in biological tissues. Tissue fixation is often required for preservation or sectioning of the tissue. This may affect collagen nanostructure and potentially provide incorrect information when analyzed after fixation. We aimed to unravel the effect of 1) ethanol and formalin fixation and 2) 24h air-dehydration on the organization and structure of collagen fibers at the nano-scale using small and wide angle X-ray scattering. Samples were divided into 4 groups: ethanol fixed, formalin fixed, and two untreated sample groups. Samples were allowed to air-dehydrate in handmade Kapton pockets during the measurements (24h) except for one untreated group. Ethanol fixation affected the collagen organization and nanostructure substantially and during 24h of dehydration dramatic changes were evident. Formalin fixation had minor effects on the collagen organization but after 12h of air-dehydration the spatial variation increased substantially, not evident in the untreated samples. Generally, collagen shrinkage and loss of alignment was evident in all samples during 24h of dehydration but the changes were subtle in all groups except the ethanol fixed samples. This study shows that tissue fixation needs to be chosen carefully in order to preserve the features of interest in the tissue. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Fractures of the proximal fifth metatarsal: percutaneous bicortical fixation.

    Science.gov (United States)

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

    2011-06-01

    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 fractures. Twenty-three fractures were operatively treated by bicortical screw fixation. All the fractures were evaluated both clinically and radiologically for the healing. All the patients were followed at 2 or 3 week intervals till fracture union. The patients were followed for an average of 22.5 months. Twenty-three fractures healed uneventfully following bicortical fixation, with a mean healing time of 6.3 weeks (range, 4 to 10 weeks). The average American Orthopaedic Foot & Ankle Society (AOFAS) score was 94 (range, 90 to 99). All the patients reported no pain at rest or during athletic activity. We removed the implant in all cases at a mean of 23.2 weeks (range, 18 to 32 weeks). There was no refracture in any of our cases. The current study shows the effectiveness of bicortical screw fixation for displaced intraarticular zone I fractures and displaced zone II fractures. We recommend it as one of the useful techniques for fixation of displaced zone I and II fractures.

  1. Local graft irradiation in renal transplant rejection

    International Nuclear Information System (INIS)

    Kawamura, Masashi; Kataoka, Masaaki; Itoh, Hisao

    1990-01-01

    From 1977 to 1988, of 142 renal transplantations, seven recipients (4.9%) received local graft irradiation following rejective reaction refractory to antirejection medical managements. Concurrent with the administration of pulsed high dose methylprednisolone and other antirejection medical managements, the graft was irradiated with a total dose of 6.0 Gy-150 cGy per fraction every other day at the midplane of the graft using two opposing portals of 4MX Linac. The fields were defined by palpation and echography. All patients had improvements in serum creatinine on the 10th day after beginning the irradiation. Four patients with peripheral lymphocytosis during the irradiation combined with pulsed high dose methylprednisolone improved in renal functions. On the other hand, out of 3 patients with lymphcytopenic changes, in two the transplanted graft was removed due to deteriorations, and the other patient is currently suffering from chronic rejection. Local graft irradiation can be useful in maintaining a rejective graft and reversing its functions in some patients whose rejective reaction failed to respond to the antirejection medical managements. (author)

  2. Graft-copolymerization onto carbon black

    International Nuclear Information System (INIS)

    Nakase, Yoshiaki; Nishii, Masanobu; Kijima, Toshiyuki; Kato, Hiroshi.

    1988-07-01

    Radiation-induced graft copolymerization of vinyl monomer onto carbon black was performed. During the γ-ray- and electron beam-induced polymerization (In-source), or the electron beam post-polymerization, the graft-copolymerization behavior was affected by the kinds of both carbon blacks and monomers, i.e. the smaller the size of carbon black particles, the higher the apparent grafted fraction. Homopolymer in the grafted carbon black samples was washed out by the solvent of the polymer, and the extracted polymer seemed to be dimer or trimer of the used monomer. In the case of the post-polymerization with the pre-irradiation doses of 50 Mrad, homopolymer was hardly observed. The polymer sheets of plastics or rubbers with grafted carbon black had an electrical conductivity unalterable considerably by the heating cycles. The particles of grafted carbon black in the sheet might be kept much more at the surface layer within 100 nm depth than at the inner layer. (author)

  3. Photoacoustic detection of neovascularities in skin graft

    Science.gov (United States)

    Yamazaki, Mutsuo; Sato, Shunichi; Saitoh, Daizo; Ishihara, Miya; Okada, Yoshiaki; Ashida, Hiroshi; Obara, Minoru

    2005-04-01

    We previously proposed a new method for monitoring adhesion of skin graft by measuring photoacoustic (PA) signal originated from the neovascularities. In this study, immunohistochemical staining (IHC) with CD31 antibody was performed for grafted skin tissue to observe neovascularity, and the results were compared with PA signals. We also used a laser Doppler imaging (LDI) to observe blood flow in the grafted skin, and sensitivity of PA measurement and that of LDI were compared. In rat autograft models, PA signals were measured for the grafted skin at postgrafting times of 0-48 h. At 6 h postgrafting, PA signal was observed in the skin depth region of 500-600 mm, while the results of IHC showed that angiogenesis occurred at the depth of about 600 mm. Depths at which PA signal and angiogenesis were observed decreased with postgrafting time. These indicate that the PA signal observed at 6 h postgrafting originated from the neovascularities in the skin graft. Results of LDI showed no blood-originated signal before 48 h postgrafting. These findings suggest that PA measurement is effective in monitoring the adhesion of skin graft in early stage after transplantation.

  4. Additive effects in radiation grafting and curing

    International Nuclear Information System (INIS)

    Viengkhou, V.; Ng, L.

    1996-01-01

    Full text: Detailed studies on the accelerative effect of novel additives in radiation grafting and curing using acrylated monomer/oligomer systems have been performed in the presence of ionising radiation and UV as sources. Methyl methacrylate (MMA) is used as typical monomer for these grafting studies in the presence of the additives with model backbone polymers, cellulose and propropylene. Additives which have been found to accelerate these grafting processes are: mineral acid, occlusion compounds like urea, thermal initiators and photoinitiators as well as multifunctional monomers such as multifunctional acrylates. The results from irradiation with gamma rays have also been compared with irradiation from a 90W UV lamp. The role of the above additives in accelerating the analogous process of radiation curing has been investigated. Acrylated urethanes, epoxies and polyesters are used as oligomers together with acrylated monomers in this work with uv lamps of 300 watts/inch as radiation source. In the UV curing process bonding between film and substrate is usually due to physical forces. In the present work the presence of additives are shown to influence the occurrence of concurrent grafting during cure thus affecting the nature of the bonding of the cured film. The conditions under which concurrent grafting with UV can occur will be examined. A mechanism for accelerative effect of these additives in both grafting and curing processes has been proposed involving radiation effects and partitioning phenomena

  5. Isotopic scintigraphy in kidney grafting

    International Nuclear Information System (INIS)

    Renfro, Richard.

    1976-01-01

    Isotopic explorations of kidney transplants were performed on sixty-six patients. Three scintigraphic techniques were used: labelled ferrous ascorbate scintigraphy, sequential 99m technetium DTPA scintigraphy and the 131 I hippuran nephrogram. The aim of this study is to analyse the results obtained under different pathological circumstances affecting the transplant, to discuss the advantages of the techniques and to propose a working procedure. The most reliable and accurate technique is the 131 I hippuran nephrogram combined with sequential 99mTc DTPA, by which renal vascularisation may be judged labelled ferrous ascorbate on the other hand is too insensitive. Although the information supplied is mostly contained in the scintigraphic images, the nephrographic curves and the blood radioactivity decay time and rad V/rad R ratio measurements are very helpful in the early diagnosis and differential diagnosis of complications affecting the transplant. The proper use of isotopic scintigraphy in kidney grafting should provide optimum conditions for better survival of the transplant at minimum risk to the patient [fr

  6. Evaluation of functional outcome of pilon fractures managed with limited internal fixation and external fixation: A prospective clinical study.

    Science.gov (United States)

    Meena, Umesh Kumar; Bansal, Mahesh Chand; Behera, Prateek; Upadhyay, Rahul; Gothwal, Gyan Chand

    2017-11-01

    The management of pilon fractures is controversial primarily due to the high rate of complications irrespective of the mode of treatment. Limited internal fixation with external fixation is associated with minimal soft tissue handling. This may reduce the chances of wound dehiscence and infection. This study was designed to evaluate the functional and clinical outcomes in patients treated with limited internal fixation combined with external fixation in pilon fractures. This study was conducted as a prospective clinical study on 56 skeletally mature patients with closed fractures with poor skin condition, and with open grade 1 and grade 2 distal tibial intra-articular fractures. All patients were treated with combined limited internal fixation and ankle spanning external fixation. All fractures in this series united with an average time period of union of 18.3weeks (ranging from 13 weeks to 30 weeks). There was no non-union in any case. There was malunion in 4 cases, varus malunion (>5 degree) in 2 cases and recurvatum in another 2 cases). Excellent to good functional results were observed in 88% cases based on the modified Ovadia and Beals score. The mean ankle dorsiflexion and planter flexion movements were 10.2±5.3 degrees and 27.4±7.2 degrees respectively. infections occurred in 6 patients which included 4 pin tract infections and 2 superficial wound infection, all 6 healed after removal of pin tract and with oral antibiotics. The technique of combined external fixation with internal fixation is safe and effective management option for intra-articular distal tibial fractures.

  7. The importance of regulation of nitrogen fixation

    Science.gov (United States)

    Menge, D. N.

    2012-12-01

    I am not a proponent of including more detail in models simply because it makes them more realistic. More complexity increases the difficulty of model interpretation, so it only makes sense to include complexity if its benefit exceeds its costs. Biological nitrogen (N) fixation (BNF) is one process for which I feel the benefits of including greater complexity far outweigh the costs. I don't think that just because I work on BNF; I work on BNF because I think that. BNF, a microbial process carried out by free-living and symbiotic microbes, is the dominant N input to many ecosystems, the primary mechanism by which N deficiency can feed back to N inputs, and a main mechanism by which N surplus can develop. The dynamics of BNF, therefore, have huge implications for the rate of carbon uptake and the extent of CO2 fertilization, as well as N export to waterways and N2O emissions to the atmosphere. Unfortunately, there are serious deficiencies in our understanding of BNF. One main deficiency in our understanding is the extent to which various symbiotic N fixing organisms respond to imbalanced nutrition. Theory suggests that these responses, which I will call "strategies," have fundamental consequences for N fixer niches and ecosystem-level N and C cycling. Organisms that fix N regardless of whether they need it, a strategy that I will call "obligate," occupy post-disturbance niches and rapidly lead to N surplus. On the contrary, organisms that only fix as much N as they need, a "facultative" strategy, can occupy a wider range of successional niches, do not produce surplus N, and respond more rapidly to increased atmospheric CO2. In this talk I will show new results showing that consideration of these strategies could on its own explain the latitudinal distribution of symbiotic N fixing trees in North America. Specifically, the transition in N-fixing tree abundance from ~10% of basal area south of 35° latitude to ~1% of basal area north of 35° latitude that we observe

  8. Surgical results of a one-stage combined anterior lumbosacral fusion and posterior percutaneous pedicle screw fixation

    Directory of Open Access Journals (Sweden)

    Chien-Yuan Huang

    2018-01-01

    Full Text Available Objectives: Lumbosacral fusion through either an anterior or a posterior approach to achieve good lordosis and stability is always a challenging surgical operation and is often accompanied by a higher rate of pseudarthrosis than when other lumbar segments are involved. This study evaluated the clinical and radiological results of lumbosacral fusions achieved through a combined anterior and posterior approach. Materials and Methods: From June 2008 to 2012, 20 patients who had L5–S1 instability and stenosis were consecutively treated, first by anterior interbody fusion using an allogenous strut bone graft through the pararectus approach and then by posterior pedicle screw fixation. A minimum of 1-year of clinical and radiological follow-up was conducted. Intraoperative blood loss, surgical time, and any surgery-related complications were recorded. Clinical outcomes were assessed using a visual analog scale (VAS and the patient's Oswestry Disability Index (ODI score. After 1 year, radiological outcomes were assessed by analyzing pelvic incidence, lumbar lordosis, and segmental lordosis using static plain films, while fusion stability was assessed using dynamic plain films. Results: The mean operative time and blood loss were 215 min and 325 cc, respectively. After 1 year, the VAS and ODI scores had significantly improved, and stable fusion with good lordotic curvature was obtained in all cases. Conclusion: The surgical results of the combined procedure are satisfactory in terms of the functional and radiological outcomes. Our method offers advantages regarding both anterior fusion and posterior fixation.

  9. The Use of Percutaneous Lumbar Fixation Screws for Bilateral Pedicle Fractures with an Associated Dislocation of a Lumbar Disc Prosthesis

    Directory of Open Access Journals (Sweden)

    William D. Harrison

    2013-01-01

    Full Text Available Study Design. Case report. Objective. To identify a safe technique for salvage surgery following complications of total disc replacement. Summary of Background Data. Lumbar total disc replacement (TDR is considered by some as the gold standard for discogenic back pain. Revision techniques for TDR and their complications are in their infancy. This case describes a successful method of fixation for this complex presentation. Methods and Results. A 48-year-old male with lumbar degenerative disc disease and no comorbidities. Approximately two weeks postoperatively for a TDR, the patient represented with acute severe back pain and the TDR polyethylene inlay was identified as dislocated anteriorly. Subsequent revision surgery failed immediately as the polyethylene inlay redislocated intraoperatively. Further radiology identified bilateral pedicle fractures, previously unseen on the plain films. The salvage fusion of L5/S1 reutilized the anterior approach with an interbody fusion cage and bone graft. The patient was then turned intraoperatively and redraped. The percutaneous pedicle screws were used to fix L5 to the sacral body via the paracoccygeal corridor. Conclusion. The robust locking screw in the percutaneous screw allowed a complete fixation of the pedicle fractures. At 3-year followup, the patient has an excellent result and has returned to playing golf.

  10. Results of triple muscle (sartorius, tensor fascia latae and part of gluteus medius pedicle bone grafting in neglected femoral neck fracture in physiologically active patients

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Mishra

    2014-01-01

    Full Text Available Background: Femoral neck fractures are notorious for complications like avascular necrosis and nonunion. In developing countries, various factors such as illiteracy, low socioeconomic status, ignorance are responsible for the delay in surgery. Neglected fracture neck femur always poses a formidable challenge. The purpose of this study was to evaluate the results of triple muscle pedicle bone grafting using sartorius, tensor fasciae latae and part of gluteus medius in neglected femoral neck fracture. Materials and Methods: This is a retrospective study with medical record of 50 patients, who were operated by open reduction, internal fixation along with muscle pedicle bone grafting by the anterior approach. After open reduction, two to three cancellous screws (6.5 mm were used for internal fixation in all cases. A bony chunk of the whole anterior superior iliac spine of 1 cm thickness, 1 cm width and 4.5 cm length, taken from the iliac crest comprised of muscle pedicle of sartorius, tensor fascia latae and part of gluteus medius. Then the graft with all three muscles mobilized and put in the trough made over the anterior or anterosuperior aspect of the femoral head. The graft was fixed with one or two 4.5 mm self-tapping cortical screw in anterior to posterior direction. Results: 14 patients were lost to followup. The results were based on 36 patients. We observed that in our series, there was union in 34, out of 36 (94.4% patients. All patients were within the age group of 15-51 years (average 38 years with displaced neglected femoral neck fracture of ≥30 days. Mean time taken for full clinicoradiological union was 14 weeks (range-10-24 weeks. Conclusion: Triple muscle pedicle bone grafting gives satisfactory results for neglected femoral neck fracture in physiologically active patients.

  11. 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)

  12. Depth of the graft bed influences split-skin graft contraction.

    NARCIS (Netherlands)

    Mensik, I.; Lamme, E.N.; Brychta, P.

    2003-01-01

    Contraction of a split-thickness skin graft used for coverage of large defects remains a great problem in plastic, burn and reconstructive surgery. In this study we evaluated healing of split-thickness skin grafts transplanted in wounds on the subcutaneous fat and muscle fascia in pigs. Four young

  13. A Prospective Study to Compare the Functional and Aesthetic Outcomes with and without Primary Bone Grafting in Facial Fractures

    Directory of Open Access Journals (Sweden)

    Narayanamurthy Sundaramurthy

    2017-10-01

    Full Text Available Introduction: Open Reduction and Internal Fixation (ORIF has been the gold standard in treatment of facial fractures. Bone grafts have been used to correct bone defects in face. Many studies assessing outcomes of ORIF and primary bone grafting separately have been published in literature. Aim: A prospective study to compare the functional and aesthetic outcomes with and without primary bone grafting in facial fractures. Materials and Methods: Thirty patients, admitted between January 2012 and December 2013, were divided into two groups. Group 1 patients underwent ORIF with primary bone grafting and in group 2, only ORIF was done. Clinical and functional, photographic and radiological assessments were done after one month and three months. Results: Mean value of vertical dystopia in groups 1 and 2 after three months postoperatively were 1.25mm and 0.67mm. Mean value of enophthalmos in groups 1 and 2 after three months postoperatively were 0.5mm and 1mm. Thus, vertical dystopia was corrected better without bone grafts and enophthalmos corrected better with bone grafts. Photographic assessment revealed no statistical difference between the two groups. Postoperatively, in upper face fractures, both groups had similar number of patients in grades 1 and 2. Only one patient from group 2 of midface fractures ended up with grade 3 asymmetry. Radiologically, in upper face fractures, group 2 had more mean projection, height and breadth deficits (1.28mm, 2.57mm and 2.42mm when compared to group 1 (0.67mm, 1.50mm and 0.50mm. The mean projection and height deficits were statistically better in group 1. In midface fractures, mean zygomatic complex projection and height deficits were more in group 2 (1.88mm and 0.63mm than group 1 (0.78mm and 0.44mm. The mean zygomatic complex projection was statistically better in group1. Postoperative complications were lesser with the bone graft group. Conclusion: Judicious use of bone grafts in comminuted facial and orbital

  14. Physical properties of agave cellulose graft polymethyl methacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Noor Afizah; Ahmad, Ishak; Abdullah, Ibrahim; Anuar, Farah Hannan [Polymer Research Centre (PORCE), School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi Selangor (Malaysia)

    2013-11-27

    The grafting polymerization of methyl methacrylate and Agave cellulose was prepared and their structural analysis and morphology were investigated. The grafting reaction was carried out in an aqueous medium using ceric ammonium nitrate as an initiator. The structural analysis of the graft copolymers was carried out by Fourier transform infrared and X-ray diffraction. The graft copolymers were also characterized by field emission scanning electron microscopy (FESEM). An additional peak at 1732 cm{sup −1} which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted Agave cellulose, respectively. Another evidence of grafting showed in the FESEM observation, where the surface of the grafted cellulose was found to be roughed than the raw one.

  15. Study on grafting glycidyl methacrylate onto HDPE membranes by pre-irradiation graft copolymerization

    International Nuclear Information System (INIS)

    Tong Long; Zu Jianhua; Liu Xinwen; Sun Guisheng; Yu Chunhui

    2006-01-01

    Glycidyl methacrylate (GMA) was grafted onto HDPE membranes by pre-irradiation method with 1.8 MeV E-beam and a kind of membranes having reactive epoxy groups was successfully synthesized. Effects of monomer concentration, reaction temperature and time and irradiation dose on the grafting yield were studied. Composition, thermo-property and surface morphology of the grafted membranes were studied by FTIR, DSC and Tapping-mode AFM, respectively. The FTIR measurements proved the synthesized copolymer is HDPE-g-GMA. The DSC results indicated the grafted HDPE's melting temperature (T m ) and heat of fusion (ΔH f ( HDPE) ) which was reduced with increasing grafting yield. The AFM images indicated that surface of the HDPE-g-GMA membranes was rougher than the virgin HDPE. (authors)

  16. Development of Highly Efficient Grafting Technique and Synthesis of Natural Polymer-Based Graft Adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Ueki, Y; Seko, N; Tamada, M [Japan Atomic Energy Agency, Quantum Beam Science Directorate, Takasaki (Japan)

    2012-09-15

    In the framework of the CRP, Japan has focused on the development of fibrous adsorbents for removal of toxic metal ions and recovery of significant metal ions from industrial wastewater and streaming water. Graft polymerization was carried out by using gamma irradiation facility and electron beam accelerator. Emulsion grafting is a novel topic for synthesis of metal ion adsorbents which are prepared from fibrous trunk polymers such as polyethylene fibre and biodegradable nonwoven fabrics. The emulsion grafting, where monomer micelles are dispersed in water in the presence of surfactant, is a highly efficient and economic grafting technique as compared to general organic solvent system. The resultant cotton-based adsorbent has high adsorption efficiency and high adsorption capacity for Hg, besides, it is biodegradable. Polylactic acid can also be used as a trunk material for the grafting. (author)

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    BACKGROUND: Harvesting techniques can affect cellular parameters of autogenous bone grafts in vitro. Whether these differences translate to in vivo bone formation, however, remains unknown. OBJECTIVE: The purpose of this study was to assess the impact of different harvesting techniques on bone fo......: Transplantation of autogenous bone particles harvested with four techniques in the present model resulted in moderate differences in terms of bone formation and graft resorption.......BACKGROUND: Harvesting techniques can affect cellular parameters of autogenous bone grafts in vitro. Whether these differences translate to in vivo bone formation, however, remains unknown. OBJECTIVE: The purpose of this study was to assess the impact of different harvesting techniques on bone...... formation and graft resorption in vivo. MATERIAL AND METHODS: Four harvesting techniques were used: (i) corticocancellous blocks particulated by a bone mill; (ii) bone scraper; (iii) piezosurgery; and (iv) bone slurry collected from a filter device upon drilling. The grafts were placed into bone defects...

  18. The emergence and early evolution of biological carbon-fixation.

    Science.gov (United States)

    Braakman, Rogier; Smith, Eric

    2012-01-01

    The fixation of CO₂ into living matter sustains all life on Earth, and embeds the biosphere within geochemistry. The six known chemical pathways used by extant organisms for this function are recognized to have overlaps, but their evolution is incompletely understood. Here we reconstruct the complete early evolutionary history of biological carbon-fixation, relating all modern pathways to a single ancestral form. We find that innovations in carbon-fixation were the foundation for most major early divergences in the tree of life. These findings are based on a novel method that fully integrates metabolic and phylogenetic constraints. Comparing gene-profiles across the metabolic cores of deep-branching organisms and requiring that they are capable of synthesizing all their biomass components leads to the surprising conclusion that the most common form for deep-branching autotrophic carbon-fixation combines two disconnected sub-networks, each supplying carbon to distinct biomass components. One of these is a linear folate-based pathway of CO₂ reduction previously only recognized as a fixation route in the complete Wood-Ljungdahl pathway, but which more generally may exclude the final step of synthesizing acetyl-CoA. Using metabolic constraints we then reconstruct a "phylometabolic" tree with a high degree of parsimony that traces the evolution of complete carbon-fixation pathways, and has a clear structure down to the root. This tree requires few instances of lateral gene transfer or convergence, and instead suggests a simple evolutionary dynamic in which all divergences have primary environmental causes. Energy optimization and oxygen toxicity are the two strongest forces of selection. The root of this tree combines the reductive citric acid cycle and the Wood-Ljungdahl pathway into a single connected network. This linked network lacks the selective optimization of modern fixation pathways but its redundancy leads to a more robust topology, making it more

  19. The emergence and early evolution of biological carbon-fixation.

    Directory of Open Access Journals (Sweden)

    Rogier Braakman

    Full Text Available The fixation of CO₂ into living matter sustains all life on Earth, and embeds the biosphere within geochemistry. The six known chemical pathways used by extant organisms for this function are recognized to have overlaps, but their evolution is incompletely understood. Here we reconstruct the complete early evolutionary history of biological carbon-fixation, relating all modern pathways to a single ancestral form. We find that innovations in carbon-fixation were the foundation for most major early divergences in the tree of life. These findings are based on a novel method that fully integrates metabolic and phylogenetic constraints. Comparing gene-profiles across the metabolic cores of deep-branching organisms and requiring that they are capable of synthesizing all their biomass components leads to the surprising conclusion that the most common form for deep-branching autotrophic carbon-fixation combines two disconnected sub-networks, each supplying carbon to distinct biomass components. One of these is a linear folate-based pathway of CO₂ reduction previously only recognized as a fixation route in the complete Wood-Ljungdahl pathway, but which more generally may exclude the final step of synthesizing acetyl-CoA. Using metabolic constraints we then reconstruct a "phylometabolic" tree with a high degree of parsimony that traces the evolution of complete carbon-fixation pathways, and has a clear structure down to the root. This tree requires few instances of lateral gene transfer or convergence, and instead suggests a simple evolutionary dynamic in which all divergences have primary environmental causes. Energy optimization and oxygen toxicity are the two strongest forces of selection. The root of this tree combines the reductive citric acid cycle and the Wood-Ljungdahl pathway into a single connected network. This linked network lacks the selective optimization of modern fixation pathways but its redundancy leads to a more robust topology

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ying-Chao Chou

    2016-04-01

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

  2. [Early application of the antibiotic-laden bone cement (ALBC) combined with the external fixation support in treating the open fractures of lower limbs complicated with bone defect].

    Science.gov (United States)

    Xiao, Jian; Mao, Zhao-Guang; Zhu, Hui-Hua; Guo, Liang

    2017-03-25

    To discuss the curative effect of the early application of the antibiotic-laden bone cement (ALBC) combined with the external fixation support in treating the open fractures of lower limbs complicated with bone defect. From December 2013 to January 2015, 36 cases of lower limb open comminuted fractures complicated with bone defects were treated by the vancomycin ALBC combined with the external fixation support, including 26 males and 10 females with an average age of 38.0 years old ranging from 19 to 65 years old. The included cases were all open fractures of lower limbs complicated with bone defects with different degree of soft tissue injuries. Among them, 25 cases were tibial fractures, 11 cases were femoral fractures. The radiographs indicated a presence of bone defects, which ranged from 3.0 to 6.1 cm with an average of 4.0 cm. The Gustilo classification of open fractures:24 cases were type IIIA, 12 cases were typr IIIB. The percentage of wound infection, bone grafting time, fracture healing time and postoperative joint function of lower limb were observed. The function of injured limbs was evaluated at 1 month after the clinical healing of fracture based on Paley evaluation criterion. All cases were followed up for 3 to 24 months with an average of (6.0±3.0) months. The wound surface was healed well, neither bone infections nor unhealed bone defects were presented. The reoperation of bone grafting was done at 6 weeks after the patients received an early treatment with ALBC, some of them were postponed to 8 weeks till the approximate healing of fractures, the treatment course lasted for 4 to 8 months with an average of(5.5±1.5) months. According to Paley and other grading evaluations of bone and function, there were 27 cases as excellent, 5 cases as good, 3 cases as ordinary. The ALBC combined with external fixation support was an effective method for early treatment to treat the traumatic lower limb open fractures complicated with bone defects. This method

  3. Baseline levels of bioaerosols and volatile organic compounds around a municipal waste incinerator prior to the construction of a mechanical-biological treatment plant

    International Nuclear Information System (INIS)

    Vilavert, Lolita; Nadal, Marti; Inza, Isabel; Figueras, Maria J.; Domingo, Jose L.

    2009-01-01

    New waste management programs are currently aimed at developing alternative treatment technologies such as mechanical-biological treatment (MBT) and composting plants. However, there is still a high uncertainty concerning the chemical and microbiological risks for human health, not only for workers of these facilities, but also for the population living in the neighborhood. A new MBT plant is planned to be constructed adjacently to a municipal solid waste incinerator (MSWI) in Tarragona (Catalonia, Spain). In order to evaluate its potential impact and to differentiate the impacts of MSWI from those of the MBT when the latter is operative, a pre-operational survey was initiated by determining the concentrations of 20 volatile organic compounds (VOCs) and bioaerosols (total bacteria, Gram-negative bacteria, fungi and Aspergillus fumigatus) in airborne samples around the MSWI. The results indicated that the current concentrations of bioaerosols (ranges: 382-3882, 18-790, 44-926, and 3 for fungi at 25 deg. C, fungi at 37 deg. C, total bacteria, and Gram-negative bacteria, respectively) and VOCs (ranging from 0.9 to 121.2 μg/m 3 ) are very low in comparison to reported levels in indoor and outdoor air in composting and MBT plants, as well in urban and industrial zones. With the exception of total bacteria, no correlations were observed between the environmental concentrations of biological agents and the direction/distance from the facility. However, total bacteria presented significantly higher levels downwind. Moreover, a non-significant increase of VOCs was detected in sites closer to the incinerator, which means that the MSWI could have a very minor impact on the surrounding environment.

  4. Adolescent External Iliac Artery Trauma: Recurrent Aneurysmal Dilatation of an Iliofemoral Saphenous Vein Graft Treated by Stent-Grafting

    International Nuclear Information System (INIS)

    Lenton, James; Davies, John; Homer-Vanniasinkam, S.; McPherson, Simon

    2008-01-01

    An adolescent male sustained a severe penetrating injury to the external iliac artery. Emergency surgical revascularization was with a reversed long saphenous vein interposition graft. The primary graft and the subsequent revision graft both became aneurysmal. The second graft aneurysm was successfully excluded by endovascular stent-grafts with medium-term primary patency. A venous graft was used initially rather than a synthetic graft to reduce the risk of infection and the potential problems from future growth. Aneurysmal dilatation of venous grafts in children and adolescents is a rare but recognized complication. To the best of our knowledge, exclusion of these aneurysms with stent-grafts has not been previously reported in the adolescent population.

  5. Corneal graft reversal: Histopathologic report of two cases.

    Science.gov (United States)

    Qahtani, Abdullah A; Alkatan, Hind M

    2014-10-01

    Graft reversal is a rare cause for failed PKP. In this case report we are presenting 2 graft failure cases in which the corneal grafts were reversed unintentionally. The onset of signs of graft failure, however was variable. We have included their clinical course and the histopathologic findings of the removed corneal grafts. A total of 6 cases including ours have been reported so far. The aim of this report is to attract the attention of corneal surgeons to an additional rare cause for failed penetrating keratoplasty (PKP) which is donor graft reversal.

  6. Grafting of acrylamide onto synthetic co polyamide by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hamoud, M R; Qamhieyh, E A [Chemistry Dept., College of Ibn Al-Haitham Baghdad university-Adhamiyah-Baghdad- (Iraq)

    1995-10-01

    Grafted copolymer was prepared by using gamma irradiation to graft acrylamide onto polymeric molecule prepared by interfacial condensation between two diamine molecules like 1,2 diamino propane and 1,6 diamino-hexane in aqueous layer with sebacoyl chloride in organic layer. The resulted co polyamide was grafted with acrylamide using gamma irradiation. The optimum conditions of grafting reaction were found, also various factors such as the effect of solvents, redox systems and the role water on the radiochemical grafting were studied. Many techniques were used in the characterization of the copolymer before and after grafting. 8 figs.,.

  7. Characterization and Some Properties of Functionalized Graft Copolymer

    International Nuclear Information System (INIS)

    Hegazy El-Sayed, A.; Kamal, H.; Mahmoud, Gh.A.; Khalifa, N.A.

    2000-01-01

    The study involved the investigation and characterization of membranes prepared by graft copolymerization of acrylonitrile (AN) and vinyl acetate (VAc) binary monomers onto low density polyethylene (LDPE) and isotactic polypropylene (IPP). The mutual gamma-irradiation method was used as a grafting technique. The effects of grafting and chemical treatments on the thermal properties and crystallinity of prepared graft copolymer have been investigated using DSC, TGA and XRD. IR spectra recorded before and after grafting and also for the chemically treated membranes to elucidate the structural changes occurred due to grafting and chemical treatments

  8. Corneal Graft Rejection: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    PURPOSE: To determine the incidence and risk factors of late corneal graft rejection after penetrating keratoplasty (PKP. METHODS: Records of all patients who had undergone PKP from 2002 to 2004 without immunosuppressive therapy other than systemic steroids and with at least one year of follow up were reviewed. The role of possible risk factors such as demographic factors, other host factors, donor factors, indications for PKP as well as type of rejection were evaluated. RESULTS: During the study period, 295 PKPs were performed on 286 patients (176 male, 110 female. Mean age at the time of keratoplasty was 38±20 (range, 40 days to 90 years and mean follow up period was 20±10 (range 12-43 months. Graft rejection occurred in 94 eyes (31.8% at an average of 7.3±6 months (range, 20 days to 39 months after PKP. The most common type of rejection was endothelial (20.7%. Corneal vascularization, regrafting, anterior synechiae, irritating sutures, active inflammation, additional anterior segment procedures, history of trauma, uncontrolled glaucoma, prior graft rejection, recurrence of herpetic infection and eccentric grafting increased the rate of rejection. Patient age, donor size and bilateral transplantation had no significant influence on graft rejection. CONCLUSION: Significant risk factors for corneal graft rejection include

  9. A new surgical technique of intra-scleral tube fixation in Ahmed Glaucoma Valve implantation: ‘Scleral Sleeve Method’

    Directory of Open Access Journals (Sweden)

    Charudutt Kalamkar

    2017-10-01

    Full Text Available Purpose: To present a new surgical technique ‘Scleral Sleeve Method’ which would reduce the risk of Ahmed Glaucoma Valve (AGV tube related complications in patients undergoing AGV FP7 (New World Medical Inc., Rancho Cucamonga, CA for refractory glaucoma. Design: Prospective, Non-Randomized, hospital based interventional case series. Subjects: A total of 16 eyes of adult patients (10 males and 6 females with refractory glaucoma. Methods: Instead of using sutures to fix the AGV tube to sclera, we devised a novel method of intra-scleral tube fixation by creating a scleral tunnel fashioned in form of sleeve. Main outcome measure: Post-operative tube related complications. Result: There were no tube related complications such as exposure, extrusion or retraction in any of the cases. Conclusion: Use of scleral sleeve method for tube fixation, along with graft to cover the tube, will provide additional safety measure and reduce the risks of tube related complications. Keywords: Ahmed Glaucoma Valve, Scleral Sleeve Method, Intra-scleral tube fixation

  10. Fixation of Light Weight Polypropylene Mesh with n-Butyl-2-cyanocrylate in Pelvic Floor Surgery: Experimental Design Approach in Sheep for Effectiveness Evaluation

    Directory of Open Access Journals (Sweden)

    Sandra Barbosa

    2015-01-01

    Full Text Available Objective. The aim of this study was to find a proper experimental design and to evaluate n-butyl-2-cyanoacrylate (Histoacryl as a fixation method for a light-weight and large pore PP mesh (Synthetic PP Mesh-1 using the sheep as an animal model. Methods. Posterior vaginal implantation by means of episiotomy was used to implant 8 ewes which were evaluated macroscopically and histologically at 3 months (n=4 and 6 months (n=4 post-surgery. In previous pilot studies anterior vaginal implantation was evaluated, as well as different synthetic mesh materials, sizes and fixation methods (n=1 to 3 during three weeks. In all cases a clinical evaluation of the animal was performed. Results. A reduction in the mesh size (Synthetic PP Mesh-1 together with precise application of the surgical glue Histoacryl to fix the mesh yielded significantly better histocompatibility results (P<0.01 compared to larger size or other fixation methods. Conclusion. The combination of Synthetic PP Mesh-1 with Histoacryl offered a high degree of graft integration without vaginal ulceration and a minimal foreign body reaction, being the sheep a proper animal model to test these types of medical devices.

  11. Severe fat embolism in perioperative abdominal liposuction and fat grafting.

    Science.gov (United States)

    de Lima E Souza, Rodrigo; Apgaua, Bruno Tavares; Milhomens, João Daniel; Albuquerque, Francisco Tadeu Motta; Carneiro, Luiz Antônio; Mendes, Márcio Henrique; Garcia, Tiago Carvalho; Paiva, Clerisson; Ladeia, Felipe; Jeunon, Deiler Célio

    2016-01-01

    Fat embolism syndrome may occur in patients suffering from multiple trauma (long bone fractures) or plastic surgery (liposuction), compromising the circulatory, respiratory and/or central nervous systems. This report shows the evolution of severe fat embolism syndrome after liposuction and fat grafting. SSS, 42 years old, ASA 1, no risk factors for thrombosis, candidate for abdominal liposuction and breast implant prosthesis. Subjected to balanced general anesthesia with basic monitoring and controlled ventilation. After 45min of procedure, there was a sudden and gradual decrease of capnometry, severe hypoxemia and hypotension. The patient was immediately monitored for MAP and central catheter, treated with vasopressors, inotropes, and crystalloid infusion, stabilizing her condition. Arterial blood sample showed pH=7.21; PCO2=51mmHg; PO2=52mmHg; BE=-8; HCO3=18mEqL(-1), and lactate=6.0mmolL(-1). Transthoracic echocardiogram showed PASP=55mmHg, hypocontractile VD and LVEF=60%. Diagnosis of pulmonary embolism. After 24h of intensive treatment, the patient developed anisocoria and coma (Glasgow coma scale=3). A brain CT was performed which showed severe cerebral hemispheric ischemia with signs of fat emboli in right middle cerebral artery; transesophageal echocardiography showed a patent foramen ovale. Finally, after 72h of evolution, the patient progressed to brain death. Fat embolism syndrome usually occurs in young people. Treatment is based mainly on the infusion of fluids and vasoactive drugs, mechanical ventilation, and triggering factor correction (early fixation of fractures or suspension of liposuction). The multiorgânico involvement indicates a worse prognosis. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  12. Metal Complexation with Chitosan and its Grafted Copolymer

    International Nuclear Information System (INIS)

    Abo-Hussen, A.A.; Elkholy, S.S.; Elsabee, M.Z.

    2005-01-01

    The adsorption of M (II); Co (II), Ni (If), Cu (II), Zn (II) and Cd (II) from aqueous solutions by chitosan flakes and beads have been studied. The maximum up-take of M (II) ions on chitosan beads was greater than on flakes. Batch adsorption experiments were carried out as a function of ph, agitation period and initial concentration of the metal ions. A ph of 6.0 was found to be optimum for M (II) adsorption on chitosan flakes and beads. The uptake of the ions was determined from the changes in its concentration, as measured by ultraviolet and visible spectroscopy. The metal ions uptake of chitosan grafted with vinyl pyridine (VP) is higher than that of the chitosan. The experimental data of the adsorption equilibrium from M (II)-solutions correlated well with the Langmuir and Freundlich equations. Several spectroscopic methods have been used to study the formation of the polymer/metal cation complex. The cation coordination is accompanied by proton displacement off the polymer or by fixation of a hydroxide ion in aqueous solutions. The largest ionic displacement is observed with Cu (II) and Zn (II) demonstrating the largest affinity of chitosan for these ions. The FT-IR spectral of the complexes show that both the amino and hydroxyl groups of chitosan participated in the chelation process. The ESR spectra of Cu-complex show an absorption at gi 2.06, g// = 2.23, A// x 10-4 (cm-1) = 160 and G = 3.8 indicating the formation of square planar structure. The adsorption of M (II) ions followed the sequence Cu (II) > Zn (II) > Cd (II) > Ni (II) > Co (II), this order seems to be independent on the size and the physical form of chitosan. SEM shows small membranous structure on the surface of chitosan flakes as compared to Cu (Il)- chitosan complex. EDTA was used for the desorption studies

  13. Prediction of coronary artery bypass graft flow

    International Nuclear Information System (INIS)

    Tamiya, Eiji; Hada, Yoshiyuki; Asano, Ken-ichi; Iio, Masahiro.

    1991-01-01

    To predict the coronary artery bypass graft (CABG) flow based on the time density curve (TDC) obtained from the digital subtraction aortograms (DSA), we developed a pulsatile CABG model (perfusion pressure 60,130 mmHg, pulse rate 53,126/min, cardiac output 3-7 l/min, diameter of the graft 2.1∼6.0 mm). After positioning the regions of interest (ROI), we injected contrast medium(5∼40 ml/sec, 5∼40 ml) into the outlet conduit. Concerning the TDCs, we calculated appearance time (Ta), peak densities (Dp), peak time (Tp), disappearance time (Td), integral of TDC, ΔTp (difference of Tp between two ROI) and ΔTa (difference of Ta between two ROI). Perfusion pressure, graft flow and output curve were similar to those of patients with CABG. Ta, Tp, Td, and ΔTp were affected by both the injection rate and the volume of the contrast medium; while Dp and the TDC integral were only affected by the latter parameter. Under the same conditions of contrast medium injection, the TDC depended strongly on graft flow, diameter of the graft, output and pulse rate. 21.6+0.92π·d 2 /4·Δ1/ΔTp·60 provided the most accurate estimation of CABG flow (r=0.865, p<0.01). We conclude that densitometric analysis of DSA may be useful in the prediction of CABG flow. (author)

  14. Long-term results of PTFE grafts.

    Science.gov (United States)

    Hedin, Ulf

    2015-01-01

    Vascular surgeons are essential in "lifeline" creation for hemodialysis patients and should be the central player in any multidisciplinary access service together with nephrologists, dialysis staff and interventional radiology. In this position, access surgeons are involved in complicated clinical decision making regarding primary and secondary access selection, which throughout the last decade has been largely aided, and influenced, by national and international guidelines as well as other initiatives. These recommendations, unanimously and appropriately, advocate the placement of native fistulas over synthetic grafts (the majority grafts from expanded polytetrafluoroethylene, ePTFE, herein referred to as PTFE) based on the superiority of fistulas with respect to complications such as infections and thrombosis. Nevertheless, the use of PTFE grafts for hemodialysis access is an accepted and firmly established alternative to native fistulas where data today reveal unwanted consequences to overinterpretation of established guidelines such as increased catheter use. This information highlights a need for an adjustment of access selection strategies based on patient-centered algorithms. Here, available results on PTFE graft performance in hemodialysis access is recapitulated, with respect to both conventional grafts and technical modifications, and conclude with a modified approach to primary access selection.

  15. Frenuloplasty with a splitthicknes skin graft

    International Nuclear Information System (INIS)

    Mohammadi, G.; Nnaderpour, M.

    2006-01-01

    The purpose of this study was to investigate the severity of presenting symptomatology in patients with ankyloglossia and to assess the surgical results of patients undergoing frenuloplasty with split thickness skin graft. During a 4 year period from September 1998 through September 2002, 19 patients of ankyloglosia underwent frenuloplasty with a split thickness skin graft. All skin grafts were taken from arm. There were 11 males and 8 females. The average length of the lingual frenulum was 3.5 mm. Twelve children were over 4 years old and were primarily operated with this technique. In the 7 patients, Z plasty had been performed previously but failed and cicatrisation caused ankyloglosia. There were two minor postoperative complications, one hematoma, and other graft dehiscence with cicatrisation. The mobility of the tongue after one year was excellent. There were no complications in donor site. Frenuloplasty with split thickness skin graft is the best and easy procedure with good results for children over 4 years and those who fail primary closure. (author)

  16. Aortic reconstruction with bovine pericardial grafts

    Directory of Open Access Journals (Sweden)

    Silveira Lindemberg Mota

    2003-01-01

    Full Text Available INTRODUCTION: Glutaraldehyde-treated crimped bovine pericardial grafts are currently used in aortic graft surgery. These conduits have become good options for these operations, available in different sizes and shapes and at a low cost. OBJECTIVE:To evaluate the results obtained with bovine pericardial grafts for aortic reconstruction, specially concerning late complications. METHOD: Between January 1995 and January 2002, 57 patients underwent different types of aortic reconstruction operations using bovine pericardial grafts. A total of 29 (50.8% were operated on an urgent basis (mostly acute Stanford A dissection and 28 electively. Thoracotomy was performed in three patients for descending aortic replacement (two patients and aortoplasty with a patch in one. All remaining 54 underwent sternotomy, cardiopulmonary bypass and aortic resection. Deep hypothermia and total circulatory arrest was used in acute dissections and arch operations. RESULTS: Hospital mortality was 17.5%. Follow-up was 24.09 months (18.5 to 29.8 months confidence interval and complication-free actuarial survival curve was 92.3% (standard deviation ± 10.6. Two patients lately developed thoracoabdominal aneurysms following previous DeBakey II dissection and one died from endocarditis. One "patch" aortoplasty patient developed local descending aortic pseudoaneurysm 42 months after surgery. All other patients are asymptomatic and currently clinically evaluated with echocardiography and CT scans, showing no complications. CONCLUSION: Use of bovine pericardial grafts in aortic reconstruction surgery is adequate and safe, with few complications related to the conduits.

  17. Penile Inversion Vaginoplasty with or without Additional Full-Thickness Skin Graft: To Graft or Not to Graft?

    Science.gov (United States)

    Buncamper, Marlon E; van der Sluis, Wouter B; de Vries, Max; Witte, Birgit I; Bouman, Mark-Bram; Mullender, Margriet G

    2017-03-01

    Penile inversion vaginoplasty is considered to be the gold standard for gender reassignment surgery in transgender women. The use of additional full-thickness skin graft as neovaginal lining is controversial. Some believe that having extra penile skin for the vulva gives better aesthetic results. Others believe that it gives inferior functional results because of insensitivity and skin graft contraction. Transgender women undergoing penile inversion vaginoplasty were studied prospectively. The option to add full-thickness skin graft is offered in patients where the penile skin length lies between 7 and 12 cm. Neovaginal depth was measured at surgery and during follow-up (3, 13, 26, and 52 weeks postoperatively). Satisfaction with the aesthetic result, neovaginal depth, and dilation regimen during follow-up were recorded. Satisfaction, sexual function, and genital self-image were assessed using questionnaires. A total of 100 patients were included (32 with and 68 without additional full-thickness skin graft). Patient-reported aesthetic outcome, overall satisfaction with the neovagina, sexual function, and genital self-image were not significantly associated with surgical technique. The mean intraoperative neovaginal depth was 13.8 ± 1.4 cm. After 1 year, this was 11.5 ± 2.5 cm. The largest decline (-15 percent) in depth is observed in the first 3 postoperative weeks (p skin graft use, in penile inversion vaginoplasty. The additional use of full-thickness skin graft does not influence neovaginal shrinkage, nor does it affect the patient- and physician-reported aesthetic or functional outcome. Therapeutic, IV.

  18. Optimizing pediatric interdental fixation by use of a paramedian palatal fixation site.

    Science.gov (United States)

    McNichols, Colton H; Hatef, Daniel A; Cole, Patrick D; Hollier, Larry H

    2012-03-01

    Condylar fractures are the most common injury seen in pediatric mandibular trauma. These injuries often cannot be adequately stabilized by conservative techniques such as splinting. The pediatric condyle fracture often requires a period of intermaxillary fixation. Because of the characteristics of the developing dentition, circumdental wiring is often not possible. Surgeons commonly achieve interdental stabilization by the connection of a circum-mandibular wire and a second wire placed through a drill hole in the piriform aperture. This method can be problematic in the young patient whose palatal suture is still patent. In this brief technical note, the use of a paramedian drill hole through the palate posterior to the maxillary incisors is described. It is believed that this method is superior to other techniques because it avoids injury to the deciduous tooth buds and allows for the maxillary wire to be seated in more structurally sound tissues.

  19. [Staple fixation for the treatment of hamate metacarpal joint injury].

    Science.gov (United States)

    Tang, Yang-Hua; Zeng, Lin-Ru; Huang, Zhong-Ming; Yue, Zhen-Shuang; Xin, Da-Wei; Xu, Can-Da

    2014-03-01

    To investigate the effcacy of the staple fixation for the treatment of hamate metacarpal joint injury. From May 2009 to November 2012,16 patients with hamate metacarpal joint injury were treated with staple fixation including 10 males and 6 females with an average age of 33.6 years old ranging from 21 to 57 years. Among them, 11 cases were on the fourth or fifth metacarpal base dislocation without fractures, 5 cases were the fourth or fifth metacarpal base dislocation with avulsion fractures of the back of hamatum. Regular X-ray review was used to observe the fracture healing, joint replacement and position of staple fixation. The function of carpometacarpal joint and metacarpophalangeal joint were evaluated according to ASIA (TAM) system evaluation method. All incision were healed well with no infection. All patients were followed up from 16 to 24 months with an average of (10.0 +/- 2.7) months. No dislocation recurred, the position of internal fixator was good,no broken nail and screw withdrawal were occurred. Five patients with avulsion fracture of the back of hamatum achieved bone healing. The function of carpometacarpal joint and metacarpophalangeal was excellent in 10 cases,good in 5 cases, moderate in 1 case. The application of the staple for the treatment of hamatometacarpal joint injury has the advantages of simple operation, small trauma, reliable fixation, early postoperative function exercise and other advantages, which is the ideal operation mode for hamatometacarpal joint injury.

  20. Relative strength of tailor's bunion osteotomies and fixation techniques.

    Science.gov (United States)

    Haddon, Todd B; LaPointe, Stephan J

    2013-01-01

    A paucity of data is available on the mechanical strength of fifth metatarsal osteotomies. The present study was designed to provide that information. Five osteotomies were mechanically tested to failure using a materials testing machine and compared with an intact fifth metatarsal using a hollow saw bone model with a sample size of 10 for each construct. The osteotomies tested were the distal reverse chevron fixated with a Kirschner wire, the long plantar reverse chevron osteotomy fixated with 2 screws, a mid-diaphyseal sagittal plane osteotomy fixated with 2 screws, the mid-diaphyseal sagittal plane osteotomy fixated with 2 screws, and an additional cerclage wire and a transverse closing wedge osteotomy fixated with a box wire technique. Analysis of variance was performed, resulting in a statistically significant difference among the data at p chevron was statistically the strongest construct at 130 N, followed by the long plantar osteotomy at 78 N. The chevron compared well with the control at 114 N, and they both fractured at the proximal model to fixture interface. The other osteotomies were statistically and significantly weaker than both the chevron and the long plantar constructs, with no statistically significant difference among them at 36, 39, and 48 N. In conclusion, the chevron osteotomy was superior in strength to the sagittal and transverse plane osteotomies and similar in strength and failure to the intact model. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  1. Comparison of cemented and uncemented fixation in total knee arthroplasty.

    Science.gov (United States)

    Brown, Thomas E; Harper, Benjamin L; Bjorgul, Kristian

    2013-05-01

    As a result of reading this article, physicians should be able to :1. Understand the rationale behind using uncemented fixation in total knee arthroplasty.2.Discuss the current literature comparing cemented and uncemented total knee arthroplasty3. Describe the value of radiostereographic analysis in assessing implant stability.4. Appreciate the limitations in the available literature advocating 1 mode of fixation in total knee arthroplasty. Total knee arthroplasty performed worldwide uses either cemented, cementless, or hybrid (cementless femur with a cemented tibia) fixation of the components. No recent literature review concerning the outcomes of cemented vs noncemented components has been performed. Noncemented components offer the potential advantage of a biologic interface between the bone and implants, which could demonstrate the greatest advantage in long-term durable fixation in the follow-up of young patients undergoing arthroplasty. Several advances have been made in the backing of the tibial components that have not been available long enough to yield long-term comparative follow-up studies. Short-term radiostereographic analysis studies have yielded differing results. Although long-term, high-quality studies are still needed, material advances in biologic fixation surfaces, such as trabecular metal and hydroxyapatite, may offer promising results for young and active patients undergoing total knee arthroplasty when compared with traditional cemented options. Copyright 2013, SLACK Incorporated.

  2. Immunohistochemistry of colorectal cancer biomarker phosphorylation requires controlled tissue fixation.

    Directory of Open Access Journals (Sweden)

    Abbey P Theiss

    Full Text Available Phosphorylated signaling molecules are biomarkers of cancer pathophysiology and resistance to therapy, but because phosphoprotein analytes are often labile, poorly controlled clinical laboratory practices could prevent translation of research findings in this area from the bench to the bedside. We therefore compared multiple biomarker and phosphoprotein immunohistochemistry (IHC results in 23 clinical colorectal carcinoma samples after either a novel, rapid tissue fixation protocol or a standard tissue fixation protocol employed by clinical laboratories, and we also investigated the effect of a defined post-operative "cold" ischemia period on these IHC results. We found that a one-hour cold ischemia interval, allowed by ASCO/CAP guidelines for certain cancer biomarker assays, is highly deleterious to certain phosphoprotein analytes, specifically the phosphorylated epidermal growth factor receptor (pEGFR, but shorter ischemic intervals (less than 17 minutes facilitate preservation of phosphoproteins. Second, we found that a rapid 4-hour, two temperature, formalin fixation yielded superior staining in several cases with select markers (pEGFR, pBAD, pAKT compared to a standard overnight room temperature fixation protocol, despite taking less time. These findings indicate that the future research and clinical utilities of phosphoprotein IHC for assessing colorectal carcinoma pathophysiology absolutely depend upon attention to preanalytical factors and rigorously controlled tissue fixation protocols.

  3. Fixation Probability in a Haploid-Diploid Population.

    Science.gov (United States)

    Bessho, Kazuhiro; Otto, Sarah P

    2017-01-01

    Classical population genetic theory generally assumes either a fully haploid or fully diploid life cycle. However, many organisms exhibit more complex life cycles, with both free-living haploid and diploid stages. Here we ask what the probability of fixation is for selected alleles in organisms with haploid-diploid life cycles. We develop a genetic model that considers the population dynamics using both the Moran model and Wright-Fisher model. Applying a branching process approximation, we obtain an accurate fixation probability assuming that the population is large and the net effect of the mutation is beneficial. We also find the diffusion approximation for the fixation probability, which is accurate even in small populations and for deleterious alleles, as long as selection is weak. These fixation probabilities from branching process and diffusion approximations are similar when selection is weak for beneficial mutations that are not fully recessive. In many cases, particularly when one phase predominates, the fixation probability differs substantially for haploid-diploid organisms compared to either fully haploid or diploid species. Copyright © 2017 by the Genetics Society of America.

  4. Fixation orientation in ankle fractures with syndesmosis injury.

    Science.gov (United States)

    Nimick, Craig J; Collman, David R; Lagaay, Pieter

    2013-01-01

    Accurate reduction of the syndesmosis has been shown to be an important prognostic factor for functional outcome in ankle injuries that disrupt the syndesmosis. The purpose of the present case series was to assess the fixation orientation and the position of the fibula within the tibial incisura after open reduction and internal fixation of ankle fractures with syndesmosis injury. Computed tomography was used to assess the accuracy of the reduction. Twelve patients were included in the present case series. A ratio representing the relationship between the tibia and fibula and the orientation of the syndesmotic fixation was measured preoperatively and postoperatively and compared with the uninjured contralateral ankle, representing the patient's normal anatomy. The measurements were accomplished electronically to one tenth of 1 mm using Stentor Intelligent Informatics, I-site, version 3.3.1 (Phillips Electronics; Andover, MA). Posteriorly oriented syndesmotic fixation caused posterior translation of the fibula with respect to the tibia and anteriorly oriented syndesmotic fixation caused anterior translation. Copyright © 2013. Published by Elsevier Inc.

  5. A COMPARATIVE STUDY OF TYMPANOPLASTY USING SLICED CARTILAGE GRAFT VS. TEMPORALIS FASCIA GRAFT

    Directory of Open Access Journals (Sweden)

    Rahul Ashok Telang

    2018-02-01

    Full Text Available BACKGROUND The objective of the study was to compare the hearing improvement after using sliced cartilage graft with that of temporalis fascia and to compare the graft take-up between the two graft materials. MATERIALS AND METHODS A prospective clinical study including 60 patients with chronic mucosal otitis media, who were selected randomly from the outpatient department, after obtaining their consent were divided into 2 groups of 30 each, and evaluated according the study protocol. Their pre-operative audiometry was recorded and both groups of patients underwent surgery with one of the graft materials- temporalis fascia or sliced tragal cartilage with a thickness of 0.5 mm. All patients were regularly followed up and post-operative audiometry was done at 3 months. The hearing improvement in the form of closure of air-bone-gap and graft take-up was analysed statistically. RESULTS The temporalis fascia graft group had a pre-operative ABG of 22.33 ± 6.24 dB and post-operative ABG of 12.33 ± 4.72 dB with hearing improvement of 10.00 dB. The sliced cartilage graft group had a pre-operative ABG of 20.77 ± 5.75 dB and postoperative ABG of 10.50 ± 4.46 dB with hearing improvement of 10.27 dB. In the temporalis fascia group, 28 (93.3% patients had good graft take-up and in the sliced cartilage group 29 (96.7% had good graft take-up. There was statistically significant hearing improvement in both of our study groups but there was no statistically significant difference between the two groups. There was no statistically significant difference in graft take-up also. CONCLUSION Sliced cartilage graft is a good auto-graft material in tympanoplasty, which can give good hearing improvement and has good graft take-up, which is comparable with that of temporalis fascia.

  6. Nonvascularized fibular grafting in nonunion of femoral neck fracture: A systematic review

    Directory of Open Access Journals (Sweden)

    Sujit Kumar Tripathy

    2016-01-01

    Full Text Available Nonunion of femoral neck fractures following primary fixation and neglected femoral neck fracture in young adults is a challenging task. Every effort should be directed toward hip joint salvage in these patients. Among different available options of hip salvage, nonvascularized fibular graft (NVFG osteosynthesis is simple, easy to perform, and a successful technique. In this review, the available literature on NVFG in neglected and nonunion femoral neck fractures has been analyzed. After review of 15 articles on NVFG, the average nonunion rate was estimated to be 7.86% (range 0-31%. Six articles that evaluated the preoperative and postoperative osteonecrosis reported improvement in 50% patients. The clinical and/or functional outcome was good to excellent in 56-96% patients following fibular osteosynthesis. Few complications such as coxa vara deformity, limb shortening, and intraarticular penetration of the graft or hardware have been reported. However, there are minimal donor site morbidities such as mild ankle pain, transient loss of toe flexors and extensors and transient lateral popliteal nerve palsy.

  7. [Localized purpura revealing vascular prosthetic graft infection].

    Science.gov (United States)

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Meshed split skin graft for extensive vitiligo

    Directory of Open Access Journals (Sweden)

    Srinivas C

    2004-05-01

    Full Text Available A 30 year old female presented with generalized stable vitiligo involving large areas of the body. Since large areas were to be treated it was decided to do meshed split skin graft. A phototoxic blister over recipient site was induced by applying 8 MOP solution followed by exposure to UVA. The split skin graft was harvested from donor area by Padgett dermatome which was meshed by an ampligreffe to increase the size of the graft by 4 times. Significant pigmentation of the depigmented skin was seen after 5 months. This procedure helps to cover large recipient areas, when pigmented donor skin is limited with minimal risk of scarring. Phototoxic blister enables easy separation of epidermis thus saving time required for dermabrasion from recipient site.

  9. [Vascular trombosis of renal graft: 9 cases].

    Science.gov (United States)

    Kaaroud, Hayet; Béji, Soumaya; Ben Hamida, Fethi; Rais, Lamia; Ben Abdallah, Taieb; El Younsi, Fethi; Ben Moussa, Fatma; Abderrahim, Ezzedine; Bardi, Rafika; Ayed, Khaled; Chebil, Mohamed; Kheder, Adel

    2008-04-01

    Allograft renal thrombosis can occur in 1 to 6% of cases. Many predisposing factors has been identified especially alteration of coagulation. We analyzed in this study frequency and predisposing factors of renal graft thrombosis. We report a retrospective study including 319 renal transplant recipients. Nine patients (2.8%) presented veinous graft thrombosis in 5 cases and arterial thombosis in 4 cases. There were 6 men and 3 women aged of 30.6 years meanly (10-56) which developed the thrombosis 6 days (1-48) after the transplantation. All patients were detransplanted after 16.2 days and 1 patient died. Thrombosis constitute an important cause of graft loss. A perfect surgical technic and prophylactic treatment in high risk patients are necessary to reduce this complication.

  10. Cartilage grafting in facial reconstruction with special consideration of irradiated grafts

    International Nuclear Information System (INIS)

    Donald, P.J.

    1986-01-01

    The search for the perfect facial implant for reconstruction of the face continues. Cartilage, once thought to be an undesirable graft material because of its propensity for absorption, has regained popularity in the past decade. Various preparation techniques have been employed to ensure graft sterility and diminished absorption. An improved understanding of cartilage structure and physiology has shed considerable light on the host-graft relationship. Gamma irradiation is a time-honored method of preservation. An experiment was undertaken to investigate the physiology of irradiated cartilage grafts following prolonged implantation on the facial skeleton of sheep and dog. Merthiolate preserved grafts were used as controls. Direct observation, histochemical techniques, autoradiography, and transmission electron micrography were used to determine chondrocyte viability and matrix composition. It was surprising to note that following implantation of 16 to 72 months, complete resorption was seen in 87.7% of the irradiated grafts and in 43.8% of the Merthiolate stored controls. Many of the grafts acquired chondrocytes from the host and produced new proteoglycan matrix as well as undergoing some degree of ossification. A comparison to the clinical situation in humans is made. 98 references

  11. Primary nerve grafting: A study of revascularization.

    Science.gov (United States)

    Chalfoun, Charbel; Scholz, Thomas; Cole, Matthew D; Steward, Earl; Vanderkam, Victoria; Evans, Gregory R D

    2003-01-01

    It was the purpose of this study to evaluate the revascularization of primary nerve repair and grafts using orthogonal polarization spectral (OPS) (Cytometrix, Inc.) imaging, a novel method for real-time evaluation of microcirculatory blood flow. Twenty male Sprague Dawley rats (250 g) were anesthetized with vaporized halothane and surgically prepared for common peroneal nerve resection. Group I animals (n = 10) underwent primary neurorraphy following transection, utilizing a microsurgical technique with 10-0 nylon suture. Group II (n = 10) animals had a 7-mm segment of nerve excised, reversed, and subsequently replaced as a nerve graft under similar techniques. All animals were evaluated using the OPS imaging system on three portions (proximal, transection site/graft, and distal) of the nerve following repair or grafting. Reevaluation of 5 animals randomly selected from each group using the OPS imaging system was again performed on days 14 and 28 following microsurgical repair/grafting. Values were determined by percent change in vascularity of the common peroneal nerve at 0 hr following surgery. Real-time evaluation of blood flow was utilized as an additional objective criterion. Percent vascularity in group I and II animals increased from baseline in all segments at day 14. By day 28, vascularity in nerves of group I rats decreased in all segments to values below baseline, with the exception of the transection site, which remained at a higher value than obtained directly after surgical repair. In group II animals, vascularity remained above baseline in all segments except the distal segment, which returned to vascularity levels similar to those at 0 hr. Further, occlusion of the vessels demonstrated in the graft and distal segments following initial transection appeared to be corrected. This study suggests that revascularization may occur via bidirectional inosculation with favored proximal vascular growth advancement. The use of real-time imaging offers a

  12. Pediatric mandibular fractures treated by rigid internal fixation.

    Science.gov (United States)

    Wong, G B

    1993-09-01

    Mandibular fractures in the pediatric patient population are relatively uncommon. These patients present with their own unique treatment requirements. Most fractures have been treated conservatively by dental splints. Closed reduction techniques with maxillomandibular fixation (MMF) in very young children can pose several concerns, including cooperation, compliance and adequate nutritional intake. Rigid internal fixation of unstable mandibular fractures using miniplates and screws circumvents the need for MMF and allows immediate jaw mobilization. At major pediatric trauma institutions, there has been an increasing trend toward the use of this treatment when open reduction is necessary. This article presents a report of a five-year-old child who presented with bilateral mandibular fractures and was treated by rigid internal fixation and immediate mandibular mobilization.

  13. Buckminsterfullerenes: a non-metal system for nitrogen fixation.

    Science.gov (United States)

    Nishibayashi, Yoshiaki; Saito, Makoto; Uemura, Sakae; Takekuma, Shin-Ichi; Takekuma, Hideko; Yoshida, Zen-Ichi

    2004-03-18

    In all nitrogen-fixation processes known so far--including the industrial Haber-Bosch process, biological fixation by nitrogenase enzymes and previously described homogeneous synthetic systems--the direct transformation of the stable, inert dinitrogen molecule (N2) into ammonia (NH3) relies on the powerful redox properties of metals. Here we show that nitrogen fixation can also be achieved by using a non-metallic buckminsterfullerene (C60) molecule, in the form of a water-soluble C60:gamma-cyclodextrin (1:2) complex, and light under nitrogen at atmospheric pressure. This metal-free system efficiently fixes nitrogen under mild conditions by making use of the redox properties of the fullerene derivative.

  14. Operative Fixation of Rib Fractures Indications, Techniques, and Outcomes.

    Science.gov (United States)

    Galos, David; Taylor, Benjamin; McLaurin, Toni

    2017-01-01

    Rib fractures are extremely common injuries and vary in there severity from single nondisplaced fractures to multiple segmental fractures resulting in flail chest and respiratory compromise. Historically, rib fractures have been treated conservatively with pain control and respiratory therapy. However this method may not be the best treatment modality in all situations. Operative fixation of select rib fractures has been increasing in popularity especially in patients with flail chest and respiratory compromise. Newer techniques use muscle sparing approaches and precontoured locking plate technology to obtain stable fixation and allow improved respiration. Current reports shows that rib fracture fixation offers the benefits of improved respiratory mechanics and improved pain control in the severe chest wall injury with resultant improvement in patient outcomes by decreasing time on the ventilator, time in the intensive care unit, and overall hospital length of stay.

  15. Single absorbable polydioxanone pin fixation for distal chevron bunion osteotomies.

    Science.gov (United States)

    Deorio, J K; Ware, A W

    2001-10-01

    The distal chevron osteotomy is a well-established technique for correction of symptomatic mild to moderate metatarsus primus varus with hallux valgus deformity. Fixation of the osteotomy ranges from none to bone pegs, Kirschner wires, screws, or absorbable pins. We evaluated one surgeon's (J.K.D.) results of distal chevron osteotomy fixation with a single, nonpredrilled, 1.3-mm poly-p-dioxanone pin and analyzed any differences in patients with unilateral or bilateral symptomatic metatarsus primus varus with hallux valgus deformities. All osteotomies healed without evidence of infection, osteolysis, nonunion, or necrosis. Equal correction was achieved in unilateral and bilateral procedures. The technique is quick and easy, and adequate fixation is achieved.

  16. How Life History Can Sway the Fixation Probability of Mutants

    Science.gov (United States)

    Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

    2016-01-01

    In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

  17. Photosynthetic and nitrogen fixation capability in several soybean mutant lines

    International Nuclear Information System (INIS)

    Gandanegara, S.; Hendratno, K.

    1987-01-01

    Photosynthetic and nitrogen fixation capability in several soybean mutant lines. A greenhouse experiment has been carried out to study photosynthetic and nitrogen fixation capability of five mutant lines and two soybean varieties. An amount of 330 uCi of 14 CO 2 was fed to the plants including of the non-fixing reference crop (Chippewa non-nodulating isoline). Nitrogen fixation measurements was carried out using 15 N isotope dilution technique according to A-value concept. Results showed that beside variety/mutant lines, plant growth also has important role in photosynthetic and N fixing capability. Better growth and a higher photosynthetic capability in Orba, mutant lines nos. 63 and 65 resulted in a greater amount of N 2 fixed (mg N/plant) than other mutant lines. (author). 12 refs.; 5 figs

  18. Infolding of fenestrated endovascular stent graft.

    Science.gov (United States)

    Zelt, Jason G E; Jetty, Prasad; Hadziomerovic, Adnan; Nagpal, Sudhir

    2017-09-01

    We report a case of infolding of a fenestrated stent graft involving the visceral vessel segment after a juxtarenal abdominal aorta aneurysm repair. The patient remains free of any significant endoleak, and the aortic sac has shown regression. The patient remains asymptomatic, with no abdominal pain, with normal renal function, and without ischemic limb complications. We hypothesize that significant graft oversizing (20%-30%) with asymmetric engineering of the diameter-reducing ties may have contributed to the infolding. Because of the patient's asymptomatic nature and general medical comorbidities, further intervention was deemed inappropriate as the aneurysmal sac is regressing despite the infolding.

  19. Expanded polytetrafluoroethylene graft fistula for chronic hemodialysis.

    Science.gov (United States)

    Tellis, V A; Kohlberg, W I; Bhat, D J; Driscoll, B; Veith, F J

    1979-01-01

    In a retrospective study of 66 PTFE arteriovenous fistulae and 71 BCH arteriovenous fistulae for dialysis access, PTFE had a higher patency rate than BCH at 12 months (62.4 versus 32.5%). PTFE was easier to work with and easier to handle in the face of infection. The lateral upper arm approach to placement of the PTFE graft is desirable in patients who have had multiple previous access procedures because this area is usually free from scarring, is distant from neurovascular structures, and provides a greater length of graft for needle punctures.

  20. Dependence of carbon dioxide concentration on microalgal carbon dioxide fixation

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Yeoung Sang; Park, Song Moon [Department of Chemical Engineering, School of Environmental Engineering, Pohang University of Science and Technology, Pohang (Korea); Bolesky, Bohumil [Department of Chemical Engineering, McGill University (Canada)

    1999-10-01

    Batch cultivation of chlorella vulgaris was carried out under various CO{sub 2} concentrations in order to understand and describe mathematically the CO{sub 2} inhibition of microalgal CO{sub 2} fixation. The volumetric CO{sub 2} transfer coefficient from mixture gas to culture medium was estimated from the volumetric O{sub 2} transfer coefficient obtained experimentally. Using this transfer coefficient and aquatic equilibrium relationship between dissolved inorganic carbons, the behavior of dissolved CO{sub 2} was calculated during microalgal culture. When air containing 0.035%(v/v) CO{sub 2} was supplied into microalgal culture, the fixation rate was limited by CO{sub 2} transfer rate. However, the limitation was disappeared by supplying mixture gas containing above 2%(v/v) CO{sub 2} and the dissolved CO{sub 2} concentration was maintained at the saturated value. In the range of CO{sub 2} partial pressure in the flue gases from thermal power sations and steel-making plants, the microalgal CO{sub 2} fixation rate was inhibited. The CO{sub 2} fixation rate was successfully formulated by a new empirical equation as a function of dissolved CO{sub 2} concentration, which could be useful for modeling and simulating the performance of photobioreaction with enriched CO{sub 2}. Also, it was found that the CO{sub 2} inhibition of microalgal CO{sub 2} fixation was reversible and that microalgal CO{sub 2} fixation process could be stable against a shock of unusually high CO{sub 2} concentration. 29 refs., 8 figs.