Internal Versus External Fixation of Charcot Midfoot Deformity Realignment.

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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.

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

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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.

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

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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.

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

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

2015-10-01

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

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

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

2017-11-07

Objective: To make a systematic assessment of the Long-term efficacy of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Methods: 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. Results: Sixteen studies involving 1 268 patients were included. There were 618 patients with open reduction and internal fixation and 650 with external fixation. The results of meta-analysis indicated that there were statistically significant differences with regard to the complications postoperatively (infection( I (2)=0%, RR =0.27, 95% CI 0.16-0.45, Z =4.92, P internal fixation and external fixation are effective treatment for unstable distal radius fractures. Compared with external fixation, open reduction and internal fixation provides reduced complications postoperatively, lower DASH scores and better restoration of volar tilt for treatment of distal radius fractures.

External fixation for closed pediatric femoral shaft fractures: where are we now?

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Kong, Heather; Sabharwal, Sanjeev

2014-12-01

Recent advances in external fixation technique and pin design have sought to minimize complications such as pin site infection and premature removal of the external fixator. Although newer forms of internal fixation have gained popularity, external fixation may still have a role in managing pediatric femoral shaft fractures. We sought to assess the time to healing, limb alignment, and complications observed in a cohort of pediatric patients with closed femoral shaft fractures who were treated with external fixation. Over a 15-year period, one surgeon treated 289 pediatric patients with femur fractures, 31 (11%) of whom received an external fixator. The general indications for use of an external fixator during the period in question included length-unstable fractures, metadiaphyseal location, refracture, and pathologic fracture. Six patients (19%) had inadequate followup data and four patients (13%) were treated with a combination of flexible intramedullary nails and external fixation, leaving 21 patients for analysis. Mean age at injury was 10 years (range, 6-15 years) and followup averaged 22 months (range, 5-45 months) after removal of the fixator. Radiographs were examined for alignment and limb length discrepancy. Complications were recorded from a chart review. Mean time in the fixator was 17 weeks (range, 9-24 weeks). One patient sustained a refracture and one patient with an isolated femur fracture had a leg length discrepancy > 2 cm. There were no pin site infections requiring intravenous antibiotics or additional surgery. One patient with Blount disease and previous tibial osteotomy developed transient peroneal nerve palsy. Despite improvements in pin design and predictable fracture healing, complications such as refracture and leg length discrepancy after external fixation of pediatric femoral shaft fractures can occur. However, external fixation remains a viable alternative for certain fractures such as length-unstable fractures, metadiaphyseal

A Novel Handmade External Fixator for Phalangeal and Metacarpal Fractures

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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.

Complex tibial plateau fractures treated by hybrid external fixation system: A correlation of followup computed tomography derived quality of reduction with clinical results

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Konstantinos Kateros

2018-01-01

Full Text Available Background: Tibial plateau fractures are common due to high energy injuries. The principles of treatment include respect for the soft tissues, restoring the congruity of the articular surface and reduction of the anatomic alignment of the lower limb to enable early movement of the knee joint. There are various surgical fixation methods that can achieve these principles of treatment. Recognition of the particular fracture pattern is important, as this guides the surgical approach required in order to adequately stabilize the fracture. This study evaluates the results of the combined treatment of external fixator and limited internal fixation along with the advantages using postoperative computed tomography (CT scan after implant removal. Materials and Methods: 55 patients with a mean age of 42 years (range 17–65 years with tibial plateau fracture, were managed in our institution between October 2010 and September 2013., Twenty fractures were classified as Schatzker VI and 35 as Schatzker V. There were 8 open fractures (2 Gustilo Anderson 3A and 6 Gustilo Anderson 2. All fractures were treated with closed reduction and hybrid external fixation (n = 21/38.2% or with minimal open reduction internal fixation and a hybrid system (n = 34/61.8%. After the removal of the fixators, CT-scan was programmed for all the cases, for correlation with the results. At final followup, the American Knee Society Score (AKSS was administered. Results: All patients were evaluated with a minimum of 12 months (range 12–21 months followup. Average time to union was 15.5 weeks (range 13–19 weeks. The postoperative joint congruity as evaluated in the postoperative CT-scan was 5° in 19 cases (35%. Patients with residual joint depression 4.5 mm displayed a 100% chance of getting poor-fair scores both in AKSS knee and AKSS function score. The association of a postoperative mechanical axis within 5° of the contralateral limb and improved knee scores was statistically

Surgical treatment of neglected clubfoot using external fixator

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Rodrigo Mota Pacheco Fernandes

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

Ball-joint versus single monolateral external fixators for definitive treatment of tibial shaft fractures.

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Beltsios, Michail; Mavrogenis, Andreas F; Savvidou, Olga D; Karamanis, Eirineos; Kokkalis, Zinon T; Papagelopoulos, Panayiotis J

2014-07-01

To compare modular monolateral external fixators with single monolateral external fixators for the treatment of open and complex tibial shaft fractures, to determine the optimal construct for fracture union. A total of 223 tibial shaft fractures in 212 patients were treated with a monolateral external fixator from 2005 to 2011; 112 fractures were treated with a modular external fixator with ball-joints (group A), and 111 fractures were treated with a single external fixator without ball-joints (group B). The mean follow-up was 2.9 years. We retrospectively evaluated the operative time for fracture reduction with the external fixator, pain and range of motion of the knee and ankle joints, time to union, rate of malunion, reoperations and revisions of the external fixators, and complications. The time for fracture reduction was statistically higher in group B; the rate of union was statistically higher in group B; the rate of nonunion was statistically higher in group A; the mean time to union was statistically higher in group A; the rate of reoperations was statistically higher in group A; and the rate of revision of the external fixator was statistically higher in group A. Pain, range of motion of the knee and ankle joints, rates of delayed union, malunion and complications were similar. Although modular external fixators are associated with faster intraoperative fracture reduction with the external fixator, single external fixators are associated with significantly better rates of union and reoperations; the rates of delayed union, malunion and complications are similar.

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

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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.

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.

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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.

[Comparison study on locking compress plate external fixator and standard external fixator for treatment of tibial open fractures].

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Wu, Gang; Luo, Xiaozhong; Tan, Lun; Lin, Xu; Wu, Chao; Guo, Yong; Zhong, Zewei

2013-11-01

To compare the clinical results of locking compress plate (LCP) as an external fixator and standard external fixator for treatment of tibial open fractures. Between May 2009 and June 2012, 59 patients with tibial open fractures were treated with LCP as an external fixator in 36 patients (group A), and with standard external fixator in 23 patients (group B). There was no significant difference in gender, age, cause of injury, affected side, type of fracture, location, and interval between injury and surgery between 2 groups (P > 0.05). The time of fracture healing and incision healing, the time of partial weight-bearing, the range of motion (ROM) of knee and ankle, and complications were compared between 2 groups. The incidence of pin-track infection in group A (0) was significantly lower than that in group B (21.7%) (P=0.007). No significant difference was found in the incidence of superficial infection and deep infection of incision, and the time of incision healing between 2 groups (P > 0.05). Deep vein thrombosis occurred in 5 cases of group A and 2 cases of group B, showing no significant difference (Chi(2)=0.036, P=0.085). All patients were followed up 15.2 months on average (range, 9-28 months) in group A, and 18.6 months on average (range, 9-47 months) in group B. The malunion rate and nonunion rate showed no significant difference between groups A and B (0 versus 13.0% and 0 versus 8.7%, P > 0.05); the delayed union rate of group A (2.8%) was significantly lower than that of group B (21.7%) (Chi(2)=5.573, P=0.018). Group A had shorter time of fracture healing, quicker partial weight-bearing, greater ROM of the knee and ankle than group B (P fracture, and has good patients' compliance, so it is helpful to do functional exercise, improve fracture healing and function recovery, and reduce the complication incidence.

Emergency department external fixation for provisional treatment of pilon and unstable ankle fractures

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Craig R Lareau

2015-01-01

Full Text Available Unstable ankle fractures and impacted tibial pilon fractures often benefit from provisional external fixation as a temporizing measure prior to definitive fixation. Benefits of external fixation include improved articular alignment, decreased articular impaction, and soft tissue rest. Uniplanar external fixator placement in the Emergency Department (ED ex-fix is a reliable and safe technique for achieving ankle reduction and stability while awaiting definitive fixation. This procedure involves placing transverse proximal tibial and calcaneal traction pins and connecting the pins with two external fixator rods. This technique is particularly useful in austere environments or when the operating room is not immediately available. Additionally, this bedside intervention prevents the patient from requiring general anesthesia and may be a cost-effective strategy for decreasing valuable operating time. The ED ex-fix is an especially valuable procedure in busy trauma centers and during mass casualty events, in which resources may be limited.

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

Hybrid fixation in the bilateral sagittal split osteotomy for lower jaw advancement

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Felipe Ladeira Pereira

2010-02-01

Full Text Available Miniplate and screw fixation has been widely used in bilateral sagittal split osteotomy, but some issues remain unclear concerning its lack of rigidity when compared to Spiessl's bicortical technique. This paper demonstrates the hybrid fixation technique in a case report. A 34-year-old female patient underwent a double jaw surgery with counter-clockwise rotation of the mandible fixed using the hybrid fixation technique. The patient evolved well in the postoperative period and is still under follow up after 14 months, reporting satisfaction with the results and no significant deviation from the treatment plan up to now. No damage to tooth roots was done, maxillomandibular range of motion was within normality and regression of the inferior alveolar nerve paresthesia was observed bilaterally. The hybrid mandibular fixation is clearly visible in the panoramic and cephalometric control radiographs. It seems that the hybrid fixation can sum the advantages of both monocortical and bicortical techniques in lower jaw advancement, increasing fixation stability without significant damage to the mandibular articulation and the inferior alveolar nerve. A statistical investigation seems necessary to prove its efficacy.

Evaluation of functional outcome of pilon fractures managed with limited internal fixation and external fixation: A prospective clinical study.

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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.

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.

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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.

DISTRACTION EXTERNAL FIXATIONS OF PELVIC FRACTURES CAUSED BY A LATERAL COMPRESSION.

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Pavlin Apostolov

2011-11-01

Full Text Available The authors represent a distraction external pelvic fixation technique, which they use in pelvic fractures caused by a lateral compression. They consider the indications and mounting techniques. The authors recommend the early movement activities (on the 3rd - 5th day after the external fixator placement. This method had been used in 8 patients and 3 cases are analyzed in details. The priority of this technique over open reduction and internal fixation (ORIF mainly are: (1 the implementation of good reduction of the fracture preventing the risk of ORIF; (2 the possibility for early movement activities for the patient.

Stress Fractures of Tibia Treated with Ilizarov External Fixator.

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Górski, Radosław; Żarek, Sławomir; Modzelewski, Piotr; Górski, Ryszard; Małdyk, Paweł

2016-08-30

Stress fractures are the result of cyclic loading of the bone, which gradually becomes damaged. Most often they are treated by rest or plaster cast and, in rare cases, by internal fixation. There is little published data on initial reposition followed by stabilization with the Ilizarov apparatus in such fractures. Six patients were treated with an external fixator according to the Ilizarov method for a stress fracture of the tibia between 2007 and 2015. Three patients were initially treated conservatively. Due to increasing tibial deformation, they were qualified for surgical treatment with external stabilization. In the other patients, surgery was the first-line treatment. All patients demonstrated risk factors for a stress fracture. After the surgery, they fully loaded the operated limb. No patient developed malunion, nonunion, infection or venous thrombosis. The average time from the first operation to the removal of the external fixator was 19 weeks. Radiographic and clinical outcomes were satisfactory in all patients. 1. The Ilizarov method allows for successful stabilization of stress fractures of the tibia. 2. It may be a good alternative to internal stabilization, especially in patients with multiple comorbidities which affect bone quality and may impair soft tissue healing.

A COMPARATIVE STUDY OF CONSERVATIVE MANAGEMENT VS. EXTERNAL FIXATION OF COMMINUTED DISTAL RADIUS FRACTURES

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Sanjeev Kumar Kare

2016-12-01

Full Text Available BACKGROUND Fracture of the distal radius (‘broken wrist’ is a common clinical problem. It can be treated conservatively usually involving wrist immobilisation in a plaster cast or surgically. A key method of surgical fixation is external fixation. MATERIALS AND METHODS A prospective study was carried out on 66 patients admitted between June 2014 to May 2016 for evaluation of conservative and surgical management of distal radius fractures. RESULTS Excellent, fair or good result was noticed in around 85% of cases managed conservatively and in above 90% of cases managed by external fixator. CONCLUSION There is some evidence to support the use of external fixation for dorsally displaced fractures of the distal radius in adults. Though, there is insufficient evidence to confirm a better functional outcome, external fixation reduces redisplacement gives improved anatomical results and most of the excess surgically-related complications are minor.

Modified fixation with pinning and external fixation components for feline femur multiple-lined fracture: A case report

International Nuclear Information System (INIS)

Okamoto, Y.; Minami, S.; Matuhashi, A.

1992-01-01

A 3-year-old female Japanese domestic cat, weighing 3kg, was referred to us because of right hind leg lameness occuring for 3 days' duration. Radiography of the affected leg revealed severe femoral diaphysial comminuted fracture. The affected leg was treated using wire with an intramedullary Stainman pin being placed completely through the femur. After suturing the wound, both ends of the intramedullary pin exposed both proximally and distally were fixed with external fixation components (two double clamps, two single clamps, two short rods and one long rod) to prevent the pin from rotation. There was a slight gait problem due to the external apparatus and no post-operative infection. The function of the right hind leg gradually recovered. The intramedullary pin and external fixative apparatus were removed on the 52nd day after surgery. This modified fixation appears to offer versatility in the treatment of various fractures in smaller dogs and cats

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

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

2017-08-01

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

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

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Büyükyilmaz, Funda; Sendir, Merdiye; Salmond, Susan

2009-01-01

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

Treatment of complex osteoarticular injuries of the elbow with external unilateral articulated fixator

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Cuellar Gallo, Lazaro; Portilla Carrillo, Armando; Calderon Uribe, Oscar; Calvache Currea, Gustavo Adolfo; Satizabal Azuero, Carlos Arnulfo

2001-01-01

Previous observations suggest that conventional treatment of complex injuries about the elbow such as open; reduction and internal Fixation might lead, to bad functional outcome. The authors present a descriptive, observational and prospective study of a series of cases, on 8 patients, average age 37.8 years (25-28 years) 6 men and 2 women with complex injury of the elbow. Due to trauma which etiology is summarized as follows intraarticular comminuted open fracture secondary to gunshot wound 5 patients (62.5%); luxofracture 2 patients (25%), lntraarticular comminuted closed fracture 1 patient (12.5%). The patients where followed for 8 to 20 months. Were performed en 75% of patients open reduction, internal fixation of radial resection of radial head en 25% when comminute fracture of the head was found. All patients were treated with an external unilateral articulated fixation on the elbow, in order to protect the internal fixation, allow early joint motion and give early mobility. All patients were evaluated with Mayo scale, obtaining good results, with externals fixation treatment. In one case (12.5%) a dyaphiseal fracture of the humerus, occurred as an inherent complication secondary to the use of the external fixation, after it's withdrawal. This patient was treated with open reduction and internal fixation of the fracture, without significant impairment of the final result. Early results suggest that the use of unilateral articulated external fixator for the treatment of complex fractures about the elbow has great advantages over the other treatment techniques, such as the early motion of the elbow, dynamic protection of the internal fixation and preservation of the articulate stability, even when ligament injury is present

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

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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

External fixation using locking plate in distal tibial fracture: a finite element analysis.

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Zhang, Jingwei; Ebraheim, Nabil; Li, Ming; He, Xianfeng; Schwind, Joshua; Liu, Jiayong; Zhu, Limei

2015-08-01

External fixation of tibial fractures using a locking plate has been reported with favorable results in some selected patients. However, the stability of external plate fixation in this fracture pattern has not been previously demonstrated. We investigated the stability of external plate fixation with different plate-bone distances. In this study, the computational processing model of external fixation of a distal tibial metaphyseal fracture utilizing the contralateral femoral less invasive stabilization system plate was analyzed. The plate was placed on the anteromedial aspect of tibia with different plate-bone distances: 1, 10, 20, and 30 mm. Under axial load, the stiffness of construct in all groups was higher than intact tibia. Under axial load with an internal rotational force, the stiffness of construct with 1 and 10 mm plate-bone distances was similar to that of an intact tibia and the stiffness of the construct with 20 and 30 mm distances was lower than that of an intact tibia. Under axial load with an external rotational force, the stiffness of the construct in all groups was lower than that of an intact tibia. The maximum plate stresses were concentrated at the two most distal screws and were highest in the construct with the 10 mm plate-bone distance, and least in the construct with a 1 mm plate-bone distance. To guarantee a stable external plate fixation in distal tibial fracture, the plate-bone distance should be less than 30 mm.

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...

Minimally invasive treatment of tibial pilon fractures through arthroscopy and external fixator-assisted reduction.

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Luo, Huasong; Chen, Liaobin; Liu, Kebin; Peng, Songming; Zhang, Jien; Yi, Yang

2016-01-01

The aim of this study was to evaluate the clinical outcome of tibial pilon fractures treated with arthroscopy and assisted reduction with an external fixator. Thirteen patients with tibial pilon fractures underwent assisted reduction for limited lower internal fixation with an external fixator under arthroscopic guidance. The weight-bearing time was decided on the basis of repeat radiography of the tibia 3 months after surgery. Postoperative ankle function was evaluated according to the Mazur scoring system. Healing of fractures was achieved in all cases, with no complications such as severe infection, skin necrosis, or an exposed plate. There were 9 excellent, 2 good, and 2 poor outcomes, scored according to the Mazur system. The acceptance rate was 85%. Arthroscopy and external fixator-assisted reduction for the minimally invasive treatment of tibial pilon fractures not only produced less trauma but also protected the soft tissues and blood supply surrounding the fractures. External fixation could indirectly provide reduction and effective operative space for arthroscopic implantation, especially for AO type B fractures and partial AO type C1 fractures.

Report About the Design of External Fixator for Treatment of Pelvis and Acetabulum Fractures

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Martin JANEČKA

2012-06-01

Full Text Available Main point in this contribution is the design of external fixators applied in traumatology and orthopaedics. These fixators can be used in the treatment of open and unstable (i.e. complicated fractures of pelvis and its acetabulum. Numerical modelling (i.e. Finite Element Method, together with CAD modelling, experiments, material engineering, and nanotechnology are presented as a support for developing of a new design of external fixators.

External versus internal fixation for bicondylar tibial plateau fractures: systematic review and meta-analysis.

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Metcalfe, David; Hickson, Craig J; McKee, Lesley; Griffin, Xavier L

2015-12-01

It is uncertain whether external fixation or open reduction internal fixation (ORIF) is optimal for patients with bicondylar tibial plateau fractures. A systematic review using Ovid MEDLINE, Embase Classic, Embase, AMED, the Cochrane Library, Open Grey, Orthopaedic Proceedings, WHO International Clinical Trials Registry Platform, Current Controlled Trials, US National Institute for Health Trials Registry, and the Cochrane Central Register of Controlled Trials. The search was conducted on 3rd October 2014 and no language limits were applied. Inclusion criteria were all clinical study designs comparing external fixation with open reduction internal fixation of bicondylar tibial plateau fractures. Studies of only one treatment modality were excluded, as were those that included unicondylar tibial plateau fractures. Treatment effects from studies reporting dichotomous outcomes were summarised using odds ratios. Continuous outcomes were converted to standardized mean differences to assess the treatment effect, and inverse variance methods used to combine data. A fixed effect model was used for meta-analyses. Patients undergoing external fixation were more likely to have returned to preinjury activities by six and twelve months (P = 0.030) but not at 24 months follow-up. However, external fixation was complicated by a greater number of infections (OR 2.59, 95 % CI 1.25-5.36, P = 0.01). There were no statistically significant differences in the rates of deep infection, venous thromboembolism, compartment syndrome, or need for re-operation between the two groups. Although external fixation and ORIF are associated with different complication profiles, both are acceptable strategies for managing bicondylar tibial plateau fractures.

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

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

2008-08-01

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

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

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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.

MANAGEMENT OF INFECTED NON UNION TIBIAL FRACTURES WITH ILIZAROV EXTERNAL FIXATION

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Nageshwara Rao

2015-10-01

Full Text Available BACKGROUND & OBJECTIVES: Infected non - union of tibia per se is a challenge to treat. Subcutaneous bone causes susceptibility to compartment syndrome, non - responsive infection, non - union, fibrosis, sinuses, deformities, shortening and various other sets of problems which are assoc iated with it. Ilizarov External fixation provides correction of all the complications associated with non - union, bone gap, infection, shortening, and deformities. Objective of this study is to assess the efficacy and safety of Ilizarov fixator method of t reatment in infected non - union tibia and to study various complications associated with Ilizarov external fixation. MATERIALS AND METHODS: 23 patients admitted and treated in Government General Hospital under the Department of Orthopaedics during the perio d of May 2010 to December 2012 were included in the study. Results were evaluated according to ASAMI criteria . 1 RESULTS : 59% patients had excellent bony results, 27.3% had good bony results, 9.1% had fair bony results, 4.6% had poor bony results. 68.1% had excellent functional results, 9.1% had good functional results, 9.1% had fair functional results, 13.7% had poor functional results. CONCLUSION : Ilizarov external fixator system is the best device and best solution for infected non - union tibia management.

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

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

2017-12-14

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

[Case-control study on effects of external fixation combined with limited internal fixation for the treatment of Pilon fractures of Rüedi-Allgower type III].

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Duan, Da-Peng; You, Wu-Lin; Ji, Le; Zhang, Yong-Tao; Dang, Xiao-Qian; Wang, Kun-Zheng

2014-01-01

To analyze the effects of three surgical operations in the treatment of Pilon fracture of Rüedi-Allgower type III, and put forward the best therapeutic method. The clinical data of 33 patients with Pilon fracture who received surgical operations (plaster immobilization group, 10 cases; distal tibia anatomical plate group, 11 cases; external fixation with limited internal fixation group, 12 cases) from October 2009 to January 2012 were analyzed. There were 5 males and 5 females, ranging in age from 24 to 61 years in the plaster immobilization group. There were 7 males and 4 females, ranging in age from 21 to 64 years in the distal tibia anatomical plate group. There were 7 males and 5 females, ranging in age from 23 to 67 years in the external fixation with limited internal fixation group. The Ankle X-ray of Pilon fracture after operation, ankle score, early and late complications were collected. Bourne system was used to evaluate ankle joint function. After 8 months to 3 years follow-up, it was found that three kinds of treatment had significant differences in the outcomes and complications (P external fixation with limited internal fixation group got the best results. The number of anatomic reduction cases in the external fixation with limited internal fixation group (7 cases) and the distal tibia anatomical plate group (8 cases) was more than the plaster immobilization group (2 cases). According to the ankle score, 8 patients got an excellent result, 3 good and 1 poor in the limited internal fixation group ,which was better than those of distal tibia anatomical plate group (5 excellent, 4 good and 2 poor) and the plaster immobilization group (3 excellent, 4 good and 3 poor). The number of early and late complications in the external fixation with limited internal fixation group was more than those in the plaster immobilization group and the distal tibia anatomical plate group (Pexternal fixation with limited internal fixation in the treatment of Pilon fracture

Use of external fixators for damage-control orthopaedics in natural disasters like the 2005 Pakistan earthquake.

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Awais, Syed; Saeed, Ayesha; Ch, Asad

2014-08-01

In the 2005 Pakistan earthquake, the great many injured with multiple fractures and open wounds provided a unique opportunity to practice damage-control orthopaedics. External fixators remain a time-tested tools for operating surgeons on such occasions. The locally manufactured, readily available Naseer-Awais (NA) external fixator filled such needs of this disaster with good outcome. This is a retrospective descriptive study of 19,700 patients that presented over seven months to the two centres established by the lead author (SMA) in Muzaffarabad and Mansehra just one night after the 2005 earthquake. A series of local and foreign orthopaedic surgeon teams operated in succession. The computerised patient data collection of 1,145 operations was retrospectively analysed. Of the 19,700 patients presenting to the SMA centres, 50% had limb injuries. Total fracture fixations were 1,145, of which 295 were external fixations: 185 were applied on the lower limb and 90 on upper limb, the majority were applied on tibia. External fixators are valuable damage-control tools in natural disasters and warfare injuries. The locally manufactured NA external fixator served the needs of the many limb injuries during the 2005 Pakistan earthquake.

Resection arthroplasty, external fixation, and negative pressure dressing for first metatarsophalangeal joint ulcers.

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Stone, Craig; Smith, Nicholas

2011-03-01

A frequent complication for the diabetic patient is neuropathic ulceration on the plantar surface of the first metatarsophalangeal (MTP) joint which can be difficult to manage. Debridement and resection arthroplasty with temporary external fixation and VAC dressing (Kinetic Concepts Inc, San Antonio, TX) is an alternative operative treatment to amputation. This study examined the outcomes of one center's experience with patients who have undergone this procedure. This retrospective cohort study examined patients who underwent the procedure between March 2002 and March 2010. Information was obtained on relevant outcomes including: the initial procedure, secondary procedures on either foot, total time in external fixation, time until amputation, cause of ulceration and co-morbid conditions. During the study period, 16 patients underwent resection arthroplasty with external fixation for first MTP ulceration. Fourteen of these patients had underlying diabetes mellitus, one had Charcot-Marie-Tooth disease and one had neuropathy of unknown cause. All were available for followup at the end of the study period. Median followup was 38 (range, 3 to 96) months. At latest followup, six patients required amputation, either transmetatarsal or transtibial, to treat their recurring ulceration. Resection arthroplasty with temporary external fixation appears to be a safe, effective and possible alternative to amputation for the treatment of neuropathic ulceration of the first MTP.

Arthroplasty of hip resection, handling with external fixation - Experience in the central military hospital

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Satizabal Azuero, Carlos E; Calderon Uribe, Oscar; Naquira Escobar, Luis F

2006-01-01

This is an observational retrospective study series of cases carried out between January 1998 and July 2004 in the central military hospital, 13 patients were treated with Girdlestone arthroplasty with external fixation, with a pursuit average of 53 months. Function, return to the daily activities and associate complications was evaluated. They were as complication; pain in the fixator site, osteitis, and fixator broke. All patients report at the end of the treatment no pain in the hip. Shortening in the patient without lenghting was 3,5 cm and in the group with lenghting was 1.5 cm. the obtained results demonstrate that Girdlestone arthroplasty with external fixation, is option, to improve the patient's pain and function of the hip

[Effectiveness comparison of flexible fixation and rigid fixation in treatment of ankle pronation-external rotation fractures with distal tibiofibular syndesmosis].

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Li, Yuewei; Zhang, Minghui; Li, Xiaorong; Chen, Xiaoyong; Deng, Jianlong

2017-07-01

To compare the effectiveness of flexible fixation and rigid fixation in the treatment of ankle pronation-external rotation fractures with distal tibiofibular syndesmosis. A retrospective analysis was made on the clinical data of 50 patients with ankle pronation-external rotation fractures and distal tibiofibular syndesmosis treated between January 2013 and December 2015. Suture-button fixation was used in 23 patients (flexible fixation group) and cortical screw fixation in 27 patients (rigid fixation group). There was no significant difference in age, gender, weight, side, fracture type, and time from trauma to surgery between 2 groups ( P >0.05). The operation time, medial clear space (MCS), tibiofibular clear space (TFCS), tibiofibular overlap (TFO), American Orthopaedic Foot and Ankle Society (AOFAS) score, and Foot and Ankle Disability Index (FADI) score were compared between 2 groups. The operation time was (83.0±9.1) minutes in the flexible fixation group and was (79.6±13.1) minutes in the rigid fixation group, showing no significant difference ( t =1.052, P =0.265). All patients achieved healing of incision by first intention. The patients were followed up 12-20 months (mean, 14 months). The X-ray films showed good healing of fracture in 2 groups. There was no screw fracture, delayed union or nounion. The fracture healing time was (12.1±2.5) months in the flexible fixation group and was (11.3±3.2) months in the rigid fixation group, showing no significant difference between 2 groups ( t =1.024, P =0.192). Reduction loss occurred after removal of screw in 2 cases of the rigid fixation group. At last follow-up, there was no significant difference in MCS, TFCS, TFO, AOFAS score and FADI score between 2 groups ( P >0.05). Suture-button fixation has similar effectiveness to screw fixation in ankle function and imaging findings, and flexible fixation has lower risk of reduction loss of distal tibiofibular syndesmosis than rigid fixation.

Outcome of complex tibial plateau fractures treated with external fixator

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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.

Biomechanical comparison of supraacetabular external fixation and anterior pelvic bridge plating.

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Çavuşoğlu, Ali Turgay; Erbay, Fatma Kübra; Özsoy, Mehmet Hakan; Demir, Teyfik

2017-10-01

Unstable pelvic ring injuries are complex and risky injuries due to high morbidity and mortality. Although anterior pelvic external fixator is a suitable method for rapid stabilization of an injured pelvic ring, due to some disadvantages such as high complication rate, nerve damage, and difficulties of patient's mobility and comfort, there has recently been increased searching for alternative methods for stabilization of the pelvic ring. Pubic symphysis zone freely moves in pelvic models. This study aims to evaluate the biomechanical stability of anterior pelvic bridge plating and compare it with supraacetabular external fixators in an untreated unstable pelvic fracture model. Samples were loaded statically with 2-mm/min loading rate in single leg standing position. Maximum load was 2.3 kN. When loading the samples, photographs were taken continuously. Stiffness values were calculated from the load displacement curves. Some reference parameters were described and were measured from unloaded and 2.3-kN-loaded photographs of the test. The mean stiffness values were 491.14 ± 52.22, 478.55 ± 41.44, and 470.25 ± 44.51 N/mm for anterior pelvic bridge plating group, supraacetabular external fixator group, and Control group, respectively. According to the measured parameters from photographs, the mean displacement at the pubic symphysis was 4.7 ± 0.32, 15.8 ± 2.01, and 18.2 ± 0.47 mm for anterior pelvic bridge plating, supraacetabular external fixator, and Control group, respectively. The highest displacement in the pubic symphysis was found in Control group, and minimum displacement was observed in anterior pelvic bridge plating group. When the perpendicular distance between the right and left lower end of ischium was examined, it was observed that displacement was minimum in anterior pelvic bridge plating group compared to other two groups, regarding to the high stability of pubic symphysis. In conclusion, this study revealed

Radial nerve injury following elbow external fixator: report of three cases and literature review.

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Trigo, Luis; Sarasquete, Juan; Noguera, Laura; Proubasta, Ignacio; Lamas, Claudia

2017-07-01

Radial nerve palsy is a rare but serious complication following elbow external fixation. Only 11 cases have been reported in the literature to date, but the incidence may be underreported. We present three new cases of this complication. We analyzed the three cases of radial palsy seen in our center following the application of an external fixator as treatment for complex elbow injuries. Mean patient age at surgery was 50 years. Two patients were female and one was male. In the three cases, the initial lesion was a posterior elbow dislocation, associated with a fracture of the radial shaft in one and a radial head fracture and coronoid fracture, respectively, in the other two. Due to persistent elbow instability, an external fixator was applied in all three cases. The fixator pins were introduced percutaneously in two cases and under direct vision in an open manner in the third case. Radial palsy was noted immediately postoperatively in all cases. It was permanent in two cases and temporary in the third. Radial nerve palsy after placement of an external elbow fixator was resolved in only 1 of our 3 cases and in 6 of the 11 cases in the literature to date. Although the event is rare, these alarming results highlight the need for recommendations to avoid this complication.

[Treatment type C fracture of the distal radius with locking compression plate and external fixators].

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Yang, Xiang; Zhao, You-ming; Chen, Lin; Ye, Cong-cong; Guo, Wei-jun; Wang, Bo

2013-12-01

To compare efficacy of unilateral external fixators and locking compression plates in treating type C fractures of the distal radius. From January 2009 to June 2010, 76 patients with distal radius fracture were treated with LCP and external fixators, 54 patients were followed up. Among them, 29 cases were male and 25 cases were female with an average age of 45.31 (ranged, 24 to 68) years old. There were 29 patients in LCP group. According to AO classification, 8 cases were type C1, 7 cases were type C2 and 14 cases were type C3. There were 25 cases in external fixators group. According to AO classification, 6 cases were type C1, 8 cases were type C2 and 11 cases were type C3. Radial height, volar tilt and radial inclination were compared, advanced Gartland-Werley scoring were used to assessed wrist joint function after 6 and 12 months' following up. Two cases were suffered from nail infection in external fixators group. Fifty-four patients were followed up from 12 to 24 months with an average of 21.3 months. Radial height was (9.60 +/- 0.72) mm, volar tilt was (9.55 +/- 0.80) degrees and radial inclination was (21.40 +/- 0.78) degrees in LCP group,while those were (9.40 +/- 0.70) mm, (9.47 +/- 0.71) degrees and (21.20 +/- 0.73) degrees in external fixtors group, and with no statistical significance (P>0.05). Advanced Gartland-Werley score after 6 months' following up was 3.31 +/- 1.17 in LCP group, 5.56 +/- 1.58 in external fixtors group, and with significant difference (t=-5.99,Pmeaning (t=-1.55, P>0.05). LCP and external fixtors can receive good curative effects in treating type C distal radius fracture, and LCP can obtain obviously short-term efficacy, while there is no significant difference between two groups in long-term results. For serious distal radius comminuted fracture which unable to plate internal fixation, external fixators is a better choice.

Salvage of infected total knee arthroplasty with Ilizarov external fixator

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Venkata Gurava Reddy

2011-01-01

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

Distal tibial pilon fractures (AO/OTA type B, and C) treated with the external skeletal and minimal internal fixation method.

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Milenković, Sasa; Mitković, Milorad; Micić, Ivan; Mladenović, Desimir; Najman, Stevo; Trajanović, Miroslav; Manić, Miodrag; Mitković, Milan

2013-09-01

Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF) and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years. The average follow-up was 21.86 (from 12 to 48) months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12-20) weeks. There were 4 (12.19%) infections around the pins of the external skeletal fixator and one (3.22%) deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90%) patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures. In

Syndesmotic fixation in supination-external rotation ankle fractures: a prospective randomized study.

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Pakarinen, Harri J; Flinkkilä, Tapio E; Ohtonen, Pasi P; Hyvönen, Pekka H; Lakovaara, Martti T; Leppilahti, Juhana I; Ristiniemi, Jukka Y

2011-12-01

This study was designed to assess whether transfixion of an unstable syndesmosis is necessary in supination-external rotation (Lauge-Hansen SE/Weber B)-type ankle fractures. A prospective study of 140 patients with unilateral Lauge-Hansen supination-external rotation type 4 ankle fractures was done. After bony fixation, the 7.5-Nm standardized external rotation (ER) stress test for both ankles was performed under fluoroscopy. A positive stress examination was defined as a difference of more than 2 mm side-to-side in the tibiotalar or tibiofibular clear spaces on mortise radiographs. If the stress test was positive, the patient was randomized to either syndesmotic transfixion with 3.5-mm tricortical screws or no syndesmotic fixation. Clinical outcome was assessed using the Olerud-Molander scoring system, RAND 36-Item Health Survey, and Visual Analogue Scale (VAS) to measure pain and function after a minimum 1-year of followup. Twenty four (17%) of 140 patients had positive standardized 7.5-Nm ER stress tests after malleolar fixation. The stress view was positive three times on tibiotalar clear space, seven on tibiofibular clear space, and 14 times on both tibiotalar and tibiofibular clear spaces. There was no significant difference between the two randomization groups with regards to Olerud-Molander functional score, VAS scale measuring pain and function, or RAND 36-Item Health Survey pain or physical function at 1 year. Relevant syndesmotic injuries are rare in supination-external rotation ankle fractures, and syndesmotic transfixion with a screw did not influence the functional outcome or pain after the 1-year followup compared with no fixation.

Distal tibial pilon fractures (AO/OTA type B, and C treated with the external skeletal and minimal internal fixation method

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Milenković Saša

2013-01-01

Full Text Available Background/Aim. Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. Methods. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. Results. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60 years. The average follow-up was 21.86 (from 12 to 48 months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12-20 weeks. There were 4 (12.19% infections around the pins of the external skeletal fixator and one (3.22% deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90% patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. Conclusion. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for

Clinical efficacy and safety of limited internal fixation combined with external fixation for Pilon fracture: A systematic review and meta-analysis

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Zhang, Shaobo; Zhang, Yibao; Wang, Shenghong; Zhang, Hua; Liu, Peng; Zhang, Wei; Ma, Jing-Lin; Wang, Jing

2017-01-01

Purpose: To compare the clinical efficacy and complications of limited internal fixation combined with external fixation (LIFEF) and open reduction and internal fixation (ORIF) in the treatment of Pilon fracture. Methods: We searched databases including Pubmed, Embase, Web of science, Cochrane Library and China Biology Medicine disc for the studies comparing clinical efficacy and complications of LIFEF and ORIF in the treatment of Pilon fracture. The clinical efficacy was evaluated by the ...

The Ilizarov external fixator: what remains of the wire pretension after dynamic loading?

NARCIS (Netherlands)

Renard, A.J.S.; Schutte, B.G.; Verdonschot, N.J.J.; Kampen, A. van

2005-01-01

BACKGROUND: Maintenance of wire pretension in an Ilizarov external fixator is dependent on the torque applied to the fixation bolts. We therefore measured immediately after surgery the clinically applied torques. The median value was only 10 N m (range 8-14N m). We wondered whether this value is

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

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Özgür Karakoyun

2014-06-01

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

External fixation is more suitable for intra-articular fractures of the distal radius in elderly patients

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Ma, Chuang; Deng, Qiang; Pu, Hongwei; Cheng, Xinchun; Kan, Yuhua; Yang, Jing; Yusufu, Aihemaitijiang; Cao, Li

2016-01-01

The purpose of this study was to compare the functional outcomes, psychological impact, and complication rates associated with external fixation and volar or dorsal plating in relation to the functional parameters following treatment of intra-articular fractures of the distal radius (IFDR) in patients older than 65 years. We hypothesized that using volar or dorsal plating would improve functional outcomes, but that it would be associated with more complications and equivalent functional outcomes when compared with the external fixation group. A total of 123 consecutive patients suffering from IFDR were recruited into the study. The patients were measured for clinical, radiological, and psychosocial functioning outcomes and were followed up after 1 week and 3, 6 and 12 months. After 3 months, the plating group had better pronation (P=0.001), supination, (P=0.047) and extension (P=0.043) scores. These differences were somewhat attenuated by 6 months and disappeared at 1 year. The plating group had a greater occurrence of wound infection (P=0.043), tendonitis, (P=0.024) and additional surgery compared with the external fixation group. The only TNO-AZL Adult Quality of Life scores in the plating group that were lower than those in the external fixation group were in the “gross motor” category (walking upstairs, bending over, walking 500 yards; P=0.023). Internal fixation was more advantageous than external fixation in the early rehabilitation period; after 1 year the outcomes were similar. The plating group showed significantly higher levels of wound infection and tendonitis and had a greater need for additional surgeries. PMID:27408765

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

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Terasa Foo

2013-01-01

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

An Overview of Internal and External Fixation Methods for the Diabetic Charcot Foot and Ankle.

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Ramanujam, Crystal L; Zgonis, Thomas

2017-01-01

Diabetic Charcot neuroarthropathy (DCN) of the foot and ankle is a challenging disease with regard to clinical presentation, pathogenesis, and prognosis. Its surgical management is equally difficult to interpret based on the wide array of options available. In the presence of an ulceration or concomitant osteomyelitis, internal fixation by means of screws, plates, or intramedullary nailing needs to be avoided when feasible. External fixation becomes a great surgical tool when managing DCN with concomitant osteomyelitis. This article describes internal and external fixation methods along with available literature to enlighten surgeons faced with treating this complex condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Functional outcome of knee arthrodesis with a monorail external fixator.

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Roy, Alfred Cyril; Albert, Sandeep; Gouse, Mohamad; Inja, Dan Barnabas

2016-04-01

Several methods for obtaining knee arthrodesis have been described in the literature and world; over, the commonest cause for arthrodesis is a failed arthroplasty. Less commonly, as in this series, post-infective or traumatic causes may also require a knee fusion wherein arthroplasty may not be indicated. We present salient advantages along with the radiological and functional outcome of twenty four patients treated with a single monorail external fixator. All patients went on develop fusion at an average of 5.4 months with an average limb length discrepancy of 3 cm (1.5-6 cm). Improvements in functional outcome as assessed by the lower extremity functional score (LEFS), and the SF-36 was significant (p = 0.000). Knee arthrodesis with a single monorail external fixator is a reasonable single-staged salvage option in patients wherein arthroplasty may not be the ideal choice. The outcome, though far from ideal, is definitely positive and predictable.

Bacteria on External Fixators: Which Prep is Best?

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2012-01-01

aureus (lux). After 12 hours in the broth, a sufficient time to allow biofilm formation ,11 the constructs were individually removed and baseline imaging...difference when cleansing components consisting of stainless steel and alumi- num.15–17 We also found that a simulated external fixator adjustment exposed...Albert E, et al. Direct continuous method for monitoring biofilm infection in a mouse model. Infect Immun. 2003;71: 882–890. 11. Charles CA, Ricotti CA

Accuracy of a hexapod parallel robot kinematics based external fixator.

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Faschingbauer, Maximilian; Heuer, Hinrich J D; Seide, Klaus; Wendlandt, Robert; Münch, Matthias; Jürgens, Christian; Kirchner, Rainer

2015-12-01

Different hexapod-based external fixators are increasingly used to treat bone deformities and fractures. Accuracy has not been measured sufficiently for all models. An infrared tracking system was applied to measure positioning maneuvers with a motorized Precision Hexapod® fixator, detecting three-dimensional positions of reflective balls mounted in an L-arrangement on the fixator, simulating bone directions. By omitting one dimension of the coordinates, projections were simulated as if measured on standard radiographs. Accuracy was calculated as the absolute difference between targeted and measured positioning values. In 149 positioning maneuvers, the median values for positioning accuracy of translations and rotations (torsions/angulations) were below 0.3 mm and 0.2° with quartiles ranging from -0.5 mm to 0.5 mm and -1.0° to 0.9°, respectively. The experimental setup was found to be precise and reliable. It can be applied to compare different hexapod-based fixators. Accuracy of the investigated hexapod system was high. Copyright © 2014 John Wiley & Sons, Ltd.

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

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

2017-12-01

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

Management of the proximal tibia fractures by mini external fixation: A case series of 30 cases

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Samar K Biswas

2014-01-01

Full Text Available Background: Management of high velocity trauma is a challenging problem because of morbidity of trauma and sometime residual problems of failure of proper healing of fractures with the restriction of movements of knee, shortening, and added risk of compartment syndrome in the proximal tibia fracture. There is always risk of post-operative infection and infected non-union in extensive open surgical procedure and internal fixation. Hence, there is always look out for the middle path procedure for a solution to the above said problems with the added advantage of less hospital stay and early return to work by minimal invasive procedure and stabilization of fracture reduction by multiple K-wire fixation with a frame applied externally. Stabilization of fracture with reduced pain allows early movements of neighbouring joint knee and ankle; hence, reduces the chances of fracture diseases. With this we have been stimulated to take-up the study of managing the proximal tibia fracture by mini external fixator. Aim: The aim of this study was to manage proximal tibia fractures by mini external fixator and evaluate the results and efficacy of this method. Material and Method: A total of 30 patients having proximal tibial fractures admitted at our center between 2008 and 2010 were taken and the procedure carried out was closed manipulative reduction and stabilization with mini external fixator. All acute proximal tibia fractures including tibial plateau fractures above 17 years of age of either sex were included in the study. Fracture more than 3 weeks old were excluded from the study. Result: Out of 30 cases 13 were excellent, 14 cases good, and 3 showed fair. It was found that type 5 and 6 of Schatzker′s classification have lesser outcome type of fractures Conclusion: We have found that management of the proximal tibia fractures by mini external fixation method has a better outcome. Early mobilization of knee in the proximal tibia fractures after

External fixation to correct tarsal-metatarsal fracture in rock pigeon (Columba livia

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Leandro Almeida Rui

Full Text Available ABSTRACT Orthopedic conditions, such as bone fractures, are very common in avian medicine. External fixators have been considered the gold standard for birds, since they allow early movement of the limbs and minimal invasive surgery. Fractures in several bones have been successfully treated in pigeons. However, to the best of our knowledge, this case represents the first report of successful surgical repair of tarsal-metatarsal fracture in rock pigeon. External fixator was made with four 24G catheters, being inserted manually proximal and distal to the fracture and connected with polymerizable acrylic. Radiographic consolidation of fracture was observed 60 days post-surgery and anti-inflammatory and antibiotic protocols were successful on avoiding pain and infection during surgery and bone healing.

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

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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.

Advantages of the Ilizarov external fixation in the management of intra-articular fractures of the distal tibia

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Kaspiris Angelos

2009-09-01

Full Text Available Abstract Background Treatment of distal tibial intra-articular fractures is challenging due to the difficulties in achieving anatomical reduction of the articular surface and the instability which may occur due to ligamentous and soft tissue injury. The purpose of this study is to present an algorithm in the application of external fixation in the management of intra-articular fractures of the distal tibia either from axial compression or from torsional forces. Materials and methods Thirty two patients with intra-articular fractures of the distal tibia have been studied. Based on the mechanism of injury they were divided into two groups. Group I includes 17 fractures due to axial compression and group II 15 fractures due to torsional force. An Ilizarov external fixation was used in 15 patients (11 of group I and 4 of group II. In 17 cases (6 of group I and 11 of group II a unilateral hinged external fixator was used. In 7 out of 17 fractures of group I an additional fixation of the fibula was performed. Results All fractures were healed. The mean time of removal of the external fixator was 11 weeks for group I and 10 weeks for group II. In group I, 5 patients had radiological osteoarthritic lesions (grade III and IV but only 2 were symptomatic. Delayed union occurred in 3 patients of group I with fixed fibula. Other complications included one patient of group II with subluxation of the ankle joint after removal of the hinged external fixator, in 2 patients reduction found to be insufficient during the postoperative follow up and were revised and 6 patients had a residual pain. The range of ankle joint motion was larger in group II. Conclusion Intra-articular fractures of the distal tibia due to axial compression are usually complicated with cartilaginous problems and are requiring anatomical reduction of the articular surface. Fractures due to torsional forces are complicated with ankle instability and reduction should be augmented with ligament

Advantages of the Ilizarov external fixation in the management of intra-articular fractures of the distal tibia

Science.gov (United States)

Vasiliadis, Elias S; Grivas, Theodoros B; Psarakis, Spyridon A; Papavasileiou, Evangelos; Kaspiris, Angelos; Triantafyllopoulos, Georgios

2009-01-01

Background Treatment of distal tibial intra-articular fractures is challenging due to the difficulties in achieving anatomical reduction of the articular surface and the instability which may occur due to ligamentous and soft tissue injury. The purpose of this study is to present an algorithm in the application of external fixation in the management of intra-articular fractures of the distal tibia either from axial compression or from torsional forces. Materials and methods Thirty two patients with intra-articular fractures of the distal tibia have been studied. Based on the mechanism of injury they were divided into two groups. Group I includes 17 fractures due to axial compression and group II 15 fractures due to torsional force. An Ilizarov external fixation was used in 15 patients (11 of group I and 4 of group II). In 17 cases (6 of group I and 11 of group II) a unilateral hinged external fixator was used. In 7 out of 17 fractures of group I an additional fixation of the fibula was performed. Results All fractures were healed. The mean time of removal of the external fixator was 11 weeks for group I and 10 weeks for group II. In group I, 5 patients had radiological osteoarthritic lesions (grade III and IV) but only 2 were symptomatic. Delayed union occurred in 3 patients of group I with fixed fibula. Other complications included one patient of group II with subluxation of the ankle joint after removal of the hinged external fixator, in 2 patients reduction found to be insufficient during the postoperative follow up and were revised and 6 patients had a residual pain. The range of ankle joint motion was larger in group II. Conclusion Intra-articular fractures of the distal tibia due to axial compression are usually complicated with cartilaginous problems and are requiring anatomical reduction of the articular surface. Fractures due to torsional forces are complicated with ankle instability and reduction should be augmented with ligament repair, in order to

Management of complex femoral nonunion with monorail external fixator: A prospective study.

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Agrawal, Hemendra Kumar; Garg, Mohit; Singh, Balvinder; Jaiman, Ashish; Khatkar, Vipin; Khare, Shailender; Batra, Sumit; Sharma, Vinod Kumar

2016-01-01

To evaluate 30 patients who underwent distraction osteogenesis with monorail external fixator for complex femoral nonunion. Complex femoral nonunion includes infective non-union, gap nonunion, and limb-length discrepancy secondary to traumatic bone loss, which needs specialized treatment to ensure the functional integrity of femoral bone. 30 patients, including 28 male and 2 female (aged 22-62 years) patients, underwent surgical debridement followed by bone transport with monorail fixator. The lengthening index, radiographic consolidation index, functional status, bone healing, and various problems, obstacles, and complications encountered during the treatment were assessed. Patients underwent a mean of 2.2 (range 1-4) surgeries before presentation. The mean bone defect after surgical debridement was 5.83 cm (range 2-16 cm). The mean treatment duration was 204.7 days (range 113-543 days). The mean lengthening index was 13.06 days/cm with range from 12 to 16 days/cm. Mean maturation index was 23.51 days/cm with range from 17 to 45.5 days/cm. In our study, bone result was excellent in 17, good in 9, fair in 3, and poor in 1 patient. In our study functional outcome is excellent in 9 [30%], good in 14 [46.67%], fair in 5, and poor in 2 patients. In our study, we encountered 34 problems, 17 obstacles, and 8 complications. We concluded that monorail external fixator is an effective treatment option for complex nonunion femoral shaft fracture and its functional outcome is comparable with any other treatment options. Lack of complications and its effectiveness makes monorail external fixator the treatment of choice for complex nonunion femoral shaft.

Two types of external fixators to correct humeral fracture in domestic pigeons

International Nuclear Information System (INIS)

Dalmolin, F.; Schossler, J.E.; Bertoletti, B.; Vasconcelos, A.; Muller, D.; Schossler, D.R.; Gomes, K.

2007-01-01

This paper was aimed at evaluating two changes in the external fixators for osteosynthesis of the humeral fracture that induce the correction of the humeral fracture in pigeons. The reduction of diaphyseal fracture was made with an intramedulary pin associated to another perpendicular one inserted into the distal segment (Group A - GA); in the Group B (GB) an additional pin was used in the proximal fragment. All the pigeons were evaluated clinically and radiographically up to 60 days, except for four of each group which were submitted to euthanasia at 15, 22, 29 and 36 days for the macro and microscope exams. The flight test was successful in all pigeons. The bone calus was radiografically visible only in the GA; the mean time and the standard deviation for flight was 32.25 ± 6.5 days for the GA and 39.8 ± 3.83 for the GB. The mean time and standard deviation for fracture healing was 36 ± 0 days in the GA and 34 ± 3.4 in the GB. The two types of external fixator evaluated were efficient to stabilized the fracture site allowing complete consolidation and return to function. The use of the external fixator with two perpendicular pins provides more stability at the fracture site although it is necessary more time for the surgery procedure [pt

Treatment of inherently unstable open or infected fractures by open wound management and external skeletal fixation.

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Ness, M G

2006-02-01

To assess the use of external skeletal fixation with open wound management for the treatment of inherently unstable open or infected fractures in dogs. A retrospective review of 10 cases. Fracture stabilisation and wound management required only a single anaesthetic, and despite the challenging nature of these injuries, the final outcome was acceptable or good in every case. However, minor complications associated with the fixator pins were quite common, and two dogs developed complications which required additional surgery. Open management of wounds, even when bone was exposed, proved to be an effective technique, and external skeletal fixators were usually effective at maintaining stability throughout an inevitably extended fracture healing period.

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

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Ivan Viktorovich Borozda

2016-02-01

Conclusions: The modular approach applied is the advantage of the transosseous osteosynthesis allowing for a separate anterior (anti-shock fixation and final posterior reposition of the pelvic ring preceded by the stabilization of vital functions. The above mentioned method gives an opportunity to increase the amount of techniques applied for the pelvic external fixation in polytrauma cases.

Intramedullary nailing of proximal and distal one-third tibial shaft fractures with intraoperative two-pin external fixation.

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Wysocki, Robert W; Kapotas, James S; Virkus, Walter W

2009-04-01

Fractures of the proximal and distal one thirds of the tibial shaft have historically higher malunion rates than those of the midshaft. This retrospective case series evaluates the postoperative radiographic outcome of intramedullary nailing of proximal and distal one-third tibial shaft fractures using intraoperative two-pin external fixation, often referred to as traveling traction. Between 2000 and 2005, 15 consecutive patients with proximal third and 27 consecutive patients with distal third displaced extra-articular fractures of the tibia were treated with statically locked intramedullary nailing and supplementary intraoperative two-pin rectangular frame external fixation. The external fixation was removed once the proximal and distal locking screws were in place. The alignment of the fractures was determined using standard postoperative anteroposterior and lateral radiographs. Postoperatively, 14 of 15 patients with proximal fractures and 25 of 27 patients with distal fractures had less than 5 degrees of angular deformity in both the coronal and sagittal planes and less than 1 cm shortening. Statically locked intramedullary nailing with simultaneous intraoperative traveling traction external fixation as treatment for proximal and distal one-third extra-articular tibial shaft fractures is successful in achieving a high rate of acceptable postoperative alignment.

EXTERNAL FIXATION OF METACARPAL AND PHALANGAL FRACTURES

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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.

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

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Zhao, Yong-gang; Ding, Jing; Wang, Neng

2011-02-01

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

[Case-control study on T-shaped locking internal fixation and external fixation for the treatment of dorsal Barton's fracture].

Science.gov (United States)

Chen, Huan-qing; Wen, Xi-le; Li, Yang-ming; Wen, Cong-you

2015-06-01

To compare clinical effect of T-shaped locking internal fixation and external fixation in treating dorsal Barton's fracture,and investigate selective strategy of internal fixation. From January 2008 to January 2013, 100 patients with dorsal Barton's fracture were randomly divided into two groups. In treatment group, there were 30 males and 20 females with an average age of (33.8±3.6) years old;30 cases were type B, 20 cases were type C;and treated with T-shaped locking internal fixation. In control group, there were 32 male and 18 females with an average age of (32.9±3.4) years old; 29 cases were type B, 21 cases were type C; and treated with external fixation. Volar tilt, ulnar deviation and radial height at 3 months after operation were detected and compared between two groups. Mechara functional evaluation were used to evaluate postoperative clinical effects. Clinical cure time, postoperative complications,joint mobility and function score were recorded and compared between two groups. In treatment group,volar tilt was (11.9±2.7)°, ulnar deviation was (20.8+ 2.9)°,and radial height was (10.9±1.8) mm; while volar tilt was (9.1±1.6)°, ulnar deviation was (17.1±2.9)°, and radial height was (8.1±1.5) mm in control group. Treatment group was better than control group in volar tilt, ulnar deviation and radial height. Clinical cure time in treatment group was(12.0±2.3) weeks, shorter than control group (18.0±4.1) weeks. The incidence of complications in treatment group was lower than control group. According to Mehara functional evaluation,20 cases got excellent results, 25 good, 3 moderate and 2 poor in treatment group; 16 cases got excellent results, 14 good, 10 moderate and 10 poor in control group. Treatment group was better than control group in clinical effects. T-shaped locking internal fixation with postoperative functional exercise for the treatment of dorsal Barton's fracture fits for biomechanics demands,and has advantages of stable fixation

Clinical and histomorphometrical study on titanium dioxide-coated external fixation pins

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Koseki H

2013-02-01

Full Text Available Hironobu Koseki,1 Tomohiko Asahara,1 Takayuki Shida,1 Itaru Yoda,1 Hidehiko Horiuchi,1 Koumei Baba,2 Makoto Osaki11Department of Orthopedic Surgery, Graduate School of Medicine, Nagasaki University, 2Industrial Technology Center of Nagasaki, Nagasaki, JapanBackground: Pin site infection is the most common and significant complication of external fixation. In this work, the efficacy of pins coated with titanium dioxide (TiO2 for inhibition of infection was compared with that of stainless steel control pins in an in vivo study.Methods: Pins contaminated with an identifiable Staphylococcus aureus strain were inserted into femoral bone in a rat model and exposed to ultraviolet A light for 30 minutes. On day 14, the animals were sacrificed and the bone and soft tissue around the pin were retrieved. The clinical findings and histological findings were evaluated in 60 samples.Results: Clinical signs of infection were present in 76.7% of untreated pins, but in only 36.7% of TiO2-coated pins. The histological bone infection score and planimetric rate of occupation for bacterial colonies and neutrophils in the TiO2-coated pin group were lower than those in the control group. The bone-implant contact ratio of the TiO2-coated pin group was significantly higher (71.4% than in the control pin group (58.2%. The TiO2 was successful in decreasing infection both clinically and histomorphometrically.Conclusion: The photocatalytic bactericidal effect of TiO2 is thought to be useful for inhibiting pin site infection after external fixation.Keywords: titanium dioxide, external fixation, bactericidal activity, Staphylococcus aureus

14CO2-fixation and nitrate reductase activity in vivo in relation to hybrid vigour in maize

International Nuclear Information System (INIS)

Balasubramanian, V.; Shanthakumari, P.; Sinha, S.K.

1977-01-01

Dry matter accumulation in maize shoots, leaf area, 14 CO 2 -fixation and nitrate reductase activity in vivo were measured in the field grown heterotic hybrid CM 400x CM 300 and its inbred parents CM 300 and CM 400 from seedling to maturity. Rates of dry matter accumulation and leaf area development were higher in the hybrid during the initial vegetative phase than in the inbreds. The hybrid had more absolute level of 14 CO 2 -fixation and nitrate reductase activity, although the rates of these processes on unit weight basis were not higher than those of inbreds. It is concluded that the rapid development of leaf area in hybrids during the early stages of vegetative growth is probably important for hybrid vigour. (author)

When do anterior external or internal fixators provide additional stability in an unstable (Tile C) pelvic fracture? A biomechanical study.

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Mcdonald, E; Theologis, A A; Horst, P; Kandemir, U; Pekmezci, M

2015-12-01

This study aimed at evaluating the additional stability that is provided by anterior external and internal fixators in an unstable pelvic fracture model (OTA 61-C). An unstable pelvic fracture (OTA 61-C) was created in 27 synthetic pelves by making a 5-mm gap through the sacral foramina (posterior injury) and an ipsilateral pubic rami fracture (anterior injury). The posterior injury was fixed with either a single iliosacral (IS) screw, a single trans-iliac, trans-sacral (TS) screw, or two iliosacral screws (S1S2). Two anterior fixation techniques were utilized: external fixation (Ex-Fix) and supra-acetabular external fixation and internal fixation (In-Fix); supra-acetabular pedicle screws connected with a single subcutaneous spinal rod. The specimens were tested using a nondestructive single-leg stance model. Peak-to-peak (P2P) displacement and rotation and conditioning displacement (CD) were calculated. The Ex-Fix group failed in 83.3 % of specimens with concomitant single-level posterior fixation (Total: 15/18-7 of 9 IS fixation, 8 of 9 TS fixation), and 0 % (0/9) of specimens with concomitant two-level (S1S2) posterior fixation. All specimens with the In-Fix survived testing except for two specimens treated with In-Fix combined with IS fixation. Trans-sacral fixation had higher pubic rotation and greater sacral and pubic displacement than S1S2 (p < 0.05). Rotation of the pubis and sacrum was not different between In-Fix constructs combined with single-level IS and TS fixation. In this model of an unstable pelvic fracture (OTA 61-C), anterior fixation with an In-Fix was biomechanically superior to an anterior Ex-Fix in the setting of single-level posterior fixation. There was no biomechanical difference between the In-Fix and Ex-Fix when each was combined with two levels of posterior sacral fixation.

Incidence and risk factors for pin tract infection in external fixation of ...

African Journals Online (AJOL)

Incidence and risk factors for pin tract infection in external fixation of fractures ... for pin tract infection, there were 93 pins scored grade 1, 32 pins grade 2, 15 ... The incidence increased from 20.5% in closed fractures to 75.9% in open fractures.

Temporary Stabilization with External Fixator in 'Tripolar' Configuration in Two Steps Treatment of Tibial Pilon Fractures.

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Daghino, Walter; Messina, Marco; Filipponi, Marco; Alessandro, Massè

2016-01-01

The tibial pilon fractures represent a complex therapeutic problem for the orthopedic surgeon, given the frequent complications and outcomes disabling. The recent medical literature indicates that the best strategy to reduce amount of complications in tibial pilon fractures is two-stages procedure. We describe our experience in the primary stabilization of these fractures. We treated 36 cases with temporary external fixation in a simple configuration, called "tripolar": this is an essential structure (only three screws and three rods), that is possible to perform even without the availability of X-rays and with simple anesthesia or sedation. We found a sufficient mechanical stability for the nursing post-operative, in absence of intraoperative and postoperative problems. The time between trauma and temporary stabilization ranged between 3 and 144 hours; surgical average time was 8.4 minutes. Definitive treatment was carried out with a delay of a minimum of 4 and a maximum of 15 days from the temporary stabilization, always without problems, both in case of ORIF (open reduction, internal fixation) or circular external fixation. Temporary stabilization with external fixator in 'tripolar' configuration seems to be the most effective strategy in two steps treatment of tibial pilon fractures. These preliminary encouraging results must be confirmed by further studies with more cases.

Humeral lengthening and proximal deformity correction with monorail external fixator in young adults.

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Ruan, Hongjiang; Zhu, Yi; Liu, Shen; Kang, Qinglin

2018-05-01

Several humeral lengthening or simultaneous deformity corrections through one osteotomy using various external fixators were reported, while literature regarding correction of shortening and proximal varus deformity is scarce. This retrospective clinical study evaluated the results of preforming an acute correction and delayed lengthening in young adults through two osteotomies using monorail external fixator. We report seven patients with various pathologies who underwent humeral proximal deformity correction and lengthening between 2009 and 2015. Pre-operative and post-operative clinical and radiographic data were collected. The mean follow-up time was 33.4 months (25-46 months). The humeral neck-shaft angle improved from 97.9° (85-110°) to 138.6° (135-145°). The magnitude of lengthening achieved was average 7.6 cm (range, 6-10 cm) at an average healing index of lengthening of 30.2 days/cm (range, 27.7-35.4 days/cm). There was a significant increase in range of shoulder abduction, and active abduction improved from pre-operative 136.4° (range, 95-160°) to post-operative 166.4° (range, 150-180°). The DASH score improved significance from 23.29 ± 8.36 to 6.57 ± 3.65 (t = 4.848; p monorail external fixator can be used for humeral shortening and proximal varus angular deformity. Functional improvement is expected after surgery and post-operative therapy.

Comparative analysis of uniplanar external fixator and retrograde intramedullary nailing for ankle arthrodesis in diabetic Charcot′s neuroarthropathy

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Nakul S Shah

2011-01-01

Results: All five (100% patients treated by intramedullary nailing achieved radiological union on an average follow-up of 16 weeks. The external fixation group had significantly higher rate of complications with one amputation, four non unions (66.7% and a delayed union which went on to full osseous union. Conclusion: The retrograde intramedullary nailing for tibio-talar arthrodesis in Charcot′s neuroarthropathy yielded significantly better outcomes as compared to the use of uniplanar external fixator.

Restriction of Postoperative Joint Loading in a Murine Model of Anterior Cruciate Ligament Reconstruction: Botulinum Toxin Paralysis and External Fixation.

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Lebaschi, Amir; Deng, Xiang-Hua; Coleman, Nathan W; Camp, Christopher L; Zong, Jianchun; Carbone, Andrew; Carballo, Camila B; Cong, Guang-Ting; Album, Zoe M; Rodeo, Scott A

2017-09-01

Control of knee motion in small animal models is necessary to study the effect of mechanical load on the healing process. This can be especially challenging in mice, which are being increasingly used for various orthopedic reconstruction models. We explored the feasibility of botulinum toxin (Botox; Allergan, Dublin, Ireland) paralysis and a newly designed external fixator to restrict motion of the knee in mice undergoing anterior cruciate ligament (ACL) reconstruction. Nineteen C57BL/6 mice were allocated to two groups: (1) Botox group ( n  = 9) and (2) external fixator group ( n  = 10). Mice in Botox group received two different doses of Botox: 0.25 unit ( n  = 3) and 0.5 unit ( n  = 6). Injection was performed 72 hours prior to ACL reconstruction into the quadriceps, hamstring, and calf muscles of the right hind leg. Mice in external fixator group received an external fixator following ACL reconstruction. Mice were monitored for survival, tolerance, and achievement of complete knee immobilization. All mice were meant for sacrifice on day 14 postoperatively. No perceptible change in gait was observed with 0.25 unit of Botox. All mice that received 0.5 unit of Botox had complete hind limb paralysis documented by footprint analysis 2 days after injection but failed to tolerate anesthesia and were euthanized 24 hours after operation due to their critical condition. In contrast, the external fixator was well tolerated and effectively immobilized the limb. There was a single occurrence of intraoperative technical error in the external fixator group that led to euthanasia. No mechanical failure or complication was observed. Botox paralysis was not a viable option for postoperative restriction of motion and joint loading in mice. However, external fixation was an effective method for complete knee immobilization and can be used in murine models requiring postoperative control of knee loading. This study introduces a robust research tool to allow control

Comparison of two-staged ORIF and limited internal fixation with external fixator for closed tibial plafond fractures.

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Wang, Cheng; Li, Ying; Huang, Lei; Wang, Manyi

2010-10-01

To compare the results of two-staged open reduction and internal fixation (ORIF) and limited internal fixation with external fixator (LIFEF) for closed tibial plafond fractures. From January 2005 to June 2007, 56 patients with closed type B3 or C Pilon fractures were randomly allocated into groups I and II. Two-staged ORIF was performed in group I and LIFEF in group II. The outcome measures included bone union, nonunion, malunion, pin-tract infection, wound infection, osteomyelitis, ankle joint function, etc. These postoperative data were analyzed with Statistical Package for Social Sciences (SPSS) 13.0. Incidence of superficial soft tissue infection (involved in wound infection or pin-tract infection) in group I was lower than that in group II (P delayed union, and arthritis symptoms, with no statistical significance. Both groups resulted similar ankle joint function. Logistic regression analysis indicated that smoking and fracture pattern were the two factors significantly influencing the final outcomes. In the treatment of closed tibial plafond fractures, both two-staged ORIF and LIFEF offer similar results. Patients undergo LIFEF carry significantly greater radiation exposure and higher superficial soft tissue infection rate (usually occurs on pin tract and does not affect the final outcomes).

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.

Comparative evaluation of in vitro mechanical properties of different designs of epoxy-pin external skeletal fixation systems.

Science.gov (United States)

Tyagi, Surbhi Kuldeep; Aithal, Hari Prasad; Kinjavdekar, Prakash; Amarpal; Pawde, Abhijit Motiram; Srivastava, Tuhin; Tyagi, Kanti Prakash; Monsang, Shongsir Warson

2014-03-01

To compare in vitro biomechanical properties of different designs of epoxy-pin external skeletal fixator (ESF) constructs. Mechanical testing study. Four epoxy-pin ESF design constructs (uniplanar [EU], multiplanar-I [EM-I], multiplanar-II [EM-II], and circular [EC]) were mechanically tested in compression, bending, and torsion. Four different designs of free-form epoxy-pin external fixator constructs were developed using 1.5 mm K-wires and epoxy resin mounted in an ultra-high density polyethylene rod (20 mm diameter). Three-point fixation was done in each fragment, and the distance between fixation wires, and between the rod and the side bars was kept constant in all the designs. A 5 mm gap was maintained at the center of the fixation rod to simulate an unstable fracture condition. The fixator constructs (n = 12 of each design) were subjected to mechanical testing in axial compression, bending, or torsion. Load-deformation curves were generated and mechanical properties were compared between construct types. EU was the weakest design. Under compression, constructs EM-I, EM-II, and EC were similar. Under bending, EM-I and EM-II had similar strength, whereas EC was strongest. Under torsion, EC was strongest, followed by EM-II, EM-I, and EU; EM-II provided double the rotational stability of EM-I. Overall, EC followed by EM-II epoxy-pin fixator designs had better mechanical strength. © Copyright 2014 by The American College of Veterinary Surgeons.

Non-invasive head fixation for external irradiation of tumors of the head and neck

International Nuclear Information System (INIS)

Bale, R.J.; Sweeney, R.; Nevinny, M.; Auer, T.; Bluhm, A.; Lukas, P.; Vogele, M.; Thumfart, W.F.

1998-01-01

Purpose: To fully utilize the technical capabilities of radiation diagnostics and planning, a precise and reproducible method of head fixation is a prerequisite. Method: We have adapted the Vogele-Bale-Hohner (VBH) head holder (Wellhoefer Dosimetrie, Schwarzenbruck, Germany), originally designed for frameless stereotactic operations, to the requirements of external beam radiotherapy. A precise and reproducible head fixation is attained by an individualized vacuum upper-dental cast which is connected over 2 hydraulic arms to an adjustable head- and rigid base-plate. Radiation field and patient alignment lasers are marked on a relocatable clear PVC localization box. Results: The possibility of craniocaudal adjustment of the head plate on the base plate allows the system to adapt to the actucal position of the patient on the raditherapy couch granting tensionless repositioning. The VBH head holder has proven itself to be a precise yet practicable method of head fixation. Duration of mouthpiece production and daily repositioning is comparable to that of the thermoplastic mask. Conclusion: The new head holder is in routine use at our hospital and quite suitable for external beam radiation of patients with tumors of the head and neck. (orig.) [de

Temporary Stabilization with External Fixator in ‘Tripolar’ Configuration in Two Steps Treatment of Tibial Pilon Fractures

Science.gov (United States)

Daghino, Walter; Messina, Marco; Filipponi, Marco; Alessandro, Massè

2016-01-01

Background: The tibial pilon fractures represent a complex therapeutic problem for the orthopedic surgeon, given the frequent complications and outcomes disabling. The recent medical literature indicates that the best strategy to reduce amount of complications in tibial pilon fractures is two-stages procedure. We describe our experience in the primary stabilization of these fractures. Methods: We treated 36 cases with temporary external fixation in a simple configuration, called "tripolar": this is an essential structure (only three screws and three rods), that is possible to perform even without the availability of X-rays and with simple anesthesia or sedation. Results: We found a sufficient mechanical stability for the nursing post-operative, in absence of intraoperative and postoperative problems. The time between trauma and temporary stabilization ranged between 3 and 144 hours; surgical average time was 8.4 minutes. Definitive treatment was carried out with a delay of a minimum of 4 and a maximum of 15 days from the temporary stabilization, always without problems, both in case of ORIF (open reduction, internal fixation) or circular external fixation Conclusion: Temporary stabilization with external fixator in ‘tripolar’ configuration seems to be the most effective strategy in two steps treatment of tibial pilon fractures. These preliminary encouraging results must be confirmed by further studies with more cases. PMID:27123151

Clinical and histomorphometrical study on titanium dioxide-coated external fixation pins.

Science.gov (United States)

Koseki, Hironobu; Asahara, Tomohiko; Shida, Takayuki; Yoda, Itaru; Horiuchi, Hidehiko; Baba, Koumei; Osaki, Makoto

2013-01-01

Pin site infection is the most common and significant complication of external fixation. In this work, the efficacy of pins coated with titanium dioxide (TiO(2)) for inhibition of infection was compared with that of stainless steel control pins in an in vivo study. Pins contaminated with an identifiable Staphylococcus aureus strain were inserted into femoral bone in a rat model and exposed to ultraviolet A light for 30 minutes. On day 14, the animals were sacrificed and the bone and soft tissue around the pin were retrieved. The clinical findings and histological findings were evaluated in 60 samples. Clinical signs of infection were present in 76.7% of untreated pins, but in only 36.7% of TiO(2)-coated pins. The histological bone infection score and planimetric rate of occupation for bacterial colonies and neutrophils in the TiO(2)-coated pin group were lower than those in the control group. The bone-implant contact ratio of the TiO(2)-coated pin group was significantly higher (71.4%) than in the control pin group (58.2%). The TiO(2) was successful in decreasing infection both clinically and histomorphometrically. The photocatalytic bactericidal effect of TiO(2) is thought to be useful for inhibiting pin site infection after external fixation.

Design and application of hybrid maxillomandibular fixation for facial bone fractures.

Science.gov (United States)

Park, Kang-Nam; Oh, Seung-Min; Lee, Chang-Youn; Kim, Jwa-Young; Yang, Byoung-Eun

2013-01-01

A novel maxillomandibular fixation (MMF) procedure using a skeletal anchorage screw (SAS) (in the maxilla) and an arch bar (in the mandible), which we call "hybrid maxillomandibular fixation," was explored in this study. The aims of the study were to examine the efficacy of our hybrid MMF method and to compare periodontal tissue health and occlusal rehabilitation among 3 MMF methods. In total, 112 patients who had undergone open reduction at the Department of Oral and Maxillofacial Surgery between September 2005 and December 2012 were selected for this study. The participants were assigned to one of the following groups: SAS (maxilla), SAS (mandible), SAS-arch bar, or arch bar-arch bar. Periodontal health was evaluated using the Gingival Index, and the perioperative occlusal reproducibility was evaluated using a score of 1 to 3. Statistical analysis was performed using parametric tests (Student t test or 1-way analysis of variance followed by post hoc Tukey test). In the Gingival Index comparison performed 1 month after the surgery, only the group using the arch bars and wiring was significantly different from the other groups (P fractures. In addition, it overcomes many problems presented by previous MMF methods.

Paediatric tibial shaft fractures treated by open reduction and stabilization with monolateral external fixation.

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Simon, A-L; Apostolou, N; Vidal, C; Ferrero, E; Mazda, K; Ilharreborde, B

2018-02-01

Elastic stable intramedullary nailing is increasingly used for surgical treatment of tibial shaft fractures, but frequently requires immobilization and delayed full weight-bearing. Therefore, external fixation remains interesting. The aim was to report clinico-radiological outcomes of monolateral external fixation for displaced and unstable tibial shaft fractures in children. All tibial fractures consecutively treated by monolateral external fixation between 2008 and 2013 were followed. Inclusion criteria included skeletal immaturity and closed and open Gustilo I fractures caused by a direct impact. Patients were seen until two years postoperatively. Demographics, mechanism of injury, surgical data and complications were recorded. Anteroposterior and lateral side radiographs were performed at each visit. Full-limb 3D reconstructions using biplanar stereroradiography was performed for final limb length and alignment measures. A total of 45 patients (mean age 9.7 years ± 0.5) were included. In all, 17 were Gustilo I fractures, with no difference between open and closed fractures for any data. Mean time to full weight bearing was 18.2 days ± 0.7. After 15 days, 39 patients returned to school. Hardware removal (mean time to union 15.6 weeks ± 0.8) was performed during consultation under analgesic gas. There were no cases of nonunion. No fracture healed with > 10° of angulation (mean 5.1° ± 0.4°). Leg-length discrepancy > 10 mm was found for six patients. This procedure can be a safe and simple surgical treatment for children with tibial shaft fractures. Few complications and early return to school were reported, with the limitations of non-comparative study. IV.

External fixation for displaced intra-articular fractures of the calcaneum.

Science.gov (United States)

Magnan, B; Bortolazzi, R; Marangon, A; Marino, M; Dall'Oca, C; Bartolozzi, P

2006-11-01

A minimally-invasive procedure using percutaneous reduction and external fixation can be carried out for Sanders' type II, III and IV fractures of the os calcis. We have treated 54 consecutive closed displaced fractures of the calcaneum involving the articular surface in 52 patients with the Orthofix Calcaneal Mini-Fixator. Patients were followed up for a mean of 49 months (27 to 94) and assessed clinically with the Maryland Foot Score and radiologically with radiographs and CT scans, evaluated according to the Score Analysis of Verona. The clinical results at follow-up were excellent or good in 49 cases (90.7%), fair in two (3.7%) and poor in three (5.6%). The mean pre-operative Böhler's angle was 6.98 degrees (5.95 degrees to 19.86 degrees), whereas after surgery the mean value was 21.94 degrees (12.58 degrees to 31.30 degrees) (p fair in three (5.6%) and poor in two (3.7%). Transient local osteoporosis was observed in ten patients (18.5%), superficial pin track infection in three (5.6%), and three patients (5.6%) showed thalamic displacement following unadvised early weight-bearing. The clinical results appear to be comparable with those obtainable with open reduction and internal fixation, with the advantages of reduced risk using a minimally-invasive technique.

Paediatric tibial shaft fractures treated by open reduction and stabilization with monolateral external fixation

Science.gov (United States)

Simon, A.-L.; Apostolou, N.; Vidal, C.; Ferrero, E.; Mazda, K.; Ilharreborde, B.

2018-01-01

Abstract Purpose Elastic stable intramedullary nailing is increasingly used for surgical treatment of tibial shaft fractures, but frequently requires immobilization and delayed full weight-bearing. Therefore, external fixation remains interesting. The aim was to report clinico-radiological outcomes of monolateral external fixation for displaced and unstable tibial shaft fractures in children. Methods All tibial fractures consecutively treated by monolateral external fixation between 2008 and 2013 were followed. Inclusion criteria included skeletal immaturity and closed and open Gustilo I fractures caused by a direct impact. Patients were seen until two years postoperatively. Demographics, mechanism of injury, surgical data and complications were recorded. Anteroposterior and lateral side radiographs were performed at each visit. Full-limb 3D reconstructions using biplanar stereroradiography was performed for final limb length and alignment measures. Results A total of 45 patients (mean age 9.7 years ± 0.5) were included. In all, 17 were Gustilo I fractures, with no difference between open and closed fractures for any data. Mean time to full weight bearing was 18.2 days ± 0.7. After 15 days, 39 patients returned to school. Hardware removal (mean time to union 15.6 weeks ± 0.8) was performed during consultation under analgesic gas. There were no cases of nonunion. No fracture healed with > 10° of angulation (mean 5.1° ± 0.4°). Leg-length discrepancy > 10 mm was found for six patients. Conclusions This procedure can be a safe and simple surgical treatment for children with tibial shaft fractures. Few complications and early return to school were reported, with the limitations of non-comparative study. Level of Evidence IV PMID:29456750

Two-stage open reduction and internal fixation versus limited internal fixation combined with external fixation: a meta-analysis of postoperative complications in patients with severe Pilon fractures.

Science.gov (United States)

Cui, Xueliang; Chen, Hui; Rui, Yunfeng; Niu, Yang; Li, He

2018-01-01

Objectives Two-stage open reduction and internal fixation (ORIF) and limited internal fixation combined with external fixation (LIFEF) are two widely used methods to treat Pilon injury. However, which method is superior to the other remains controversial. This meta-analysis was performed to quantitatively compare two-stage ORIF and LIFEF and clarify which method is better with respect to postoperative complications in the treatment of tibial Pilon fractures. Methods We conducted a meta-analysis to quantitatively compare the postoperative complications between two-stage ORIF and LIFEF. Eight studies involving 360 fractures in 359 patients were included in the meta-analysis. Results The two-stage ORIF group had a significantly lower risk of superficial infection, nonunion, and bone healing problems than the LIFEF group. However, no significant differences in deep infection, delayed union, malunion, arthritis symptoms, or chronic osteomyelitis were found between the two groups. Conclusion Two-stage ORIF was associated with a lower risk of postoperative complications with respect to superficial infection, nonunion, and bone healing problems than LIFEF for tibial Pilon fractures. Level of evidence 2.

Minimally invasive plate osteosynthesis for humeral shaft fracture: a reproducible technique with the assistance of an external fixator.

Science.gov (United States)

Lee, Hyun-Joo; Oh, Chang-Wug; Oh, Jong-Keon; Apivatthakakul, Theerachai; Kim, Joon-Woo; Yoon, Jong-Pil; Lee, Dong-Joo; Jung, Jae-Wook

2013-05-01

Minimally invasive plate osteosynthesis (MIPO) has become a popular option for treatment of humeral shaft fractures. However, indirect reduction might risk unpromising results, with mal-alignment/mal-union or nonunion. The purpose of this study was to describe a reproducible MIPO technique that used an external fixator during the procedure as a tool for reduction and maintenance, and to assess the outcomes in patients with humeral shaft fracture. Of 31 consecutive cases of humeral shaft fracture in 30 patients, 29 were included in this study. There were seven simple (type A) and 22 comminuted (type B or C) fractures. After the insertion of one Schanz pin on each proximal and distal humerus, a provisional reduction was achieved by connecting the pins with a monolateral external fixator. The MIPO procedure was then performed over the anterior aspect of the humerus. To evaluate the efficacy of the provisional reduction by external fixator, coronal and sagittal alignments were assessed. We also assessed bony and functional results, including complications, from this technique. There was no case of mal-union >10°, and mean angulation was 1.3° (range 0°-9°) in the coronal plane and 1.2° (range 0°-8°) in the sagittal plane. Twenty-eight of 29 fractures were united, including three delayed unions, with a mean union time of 19.1 weeks (range 12.3-38.4 weeks) and a mean follow-up of 20.8 months (range 13.5-31.0 months). There was one hypertrophic nonunion that healed after fixing with two additional screws. Except one patient with associated injury in the elbow, all patients recovered to pre-injury joint motion. There were two cases of postoperative radial nerve palsy that both recovered completely. We attributed them to manipulation, and not to the Schanz pins or plate fixation. Surgical treatment of humeral shaft fractures with external fixator-assisted reduction and MIPO resulted in excellent reductions and high union rates.

A prospective study of dynamic treatment of fracture phalanx and metacarpals of the hand with Kirschner-wire fixation/external fixator and finger splint: Daycare management (30 cases

Directory of Open Access Journals (Sweden)

Rahul Madhukar Salunkhe

2016-01-01

Full Text Available Introduction: Fractures of the phalanx and metacarpals are some of the most frequently encountered orthopedics injuries and constitute between 14-28% of all visits to emergency department which comprises 46% of the hand fracture and out of that mostly involved are the proximal phalanx and metacarpal neck fracture are most common and then the middle and distal phalanx and the base of metacarpal. The commonest complication with surgical treatment were stiff painful joints due to prolonged immobilization at fracture sites. This prospective study was undertaken to evaluate the functional outcome after surgical stabilization of metacarpal and phalanx fracture on day care basis. Materials And Methods: In our study we treated 30 patients who came to our hospital by fixation either with K wire or external fixation or hybrid fixation under local anaesthesia depending on the type of fracture between 2013 to 2014 with the average age 28 years with the youngest being 18 years and the oldest being 41 years with transverse, spiral, oblique closed fracture, grade 1 compound fracture, intraarticular, extraarticular, comminuted and non comminuted fracture of phalanx and metacarpals.These were day care treatment. Patient was allowed to begin his daily routine work from post operative day l. During this course the operated site was protected with splinting. Results: Clinical Outcomes were assessed as Excellent, Good, Satisfactory and Poor. Radiological assessment was done by taking x-ray to check radiological union.There were 24 cases had excellent outcome, 5 cases had good outcome and only 1 case had satisfactory outcome which occurred due to mal-union. There were 3 cases of pin-tract infection which subsided with oral antibiotics, and 3 cases of malunion. Conclusion: This was a day care procedure, patient were admitted, treated and discharged on the same day & encouraged to begin mobilization of the joints of hands from day 1.

Distal tibial fracture treated by minimally invasive plate osteosynthesis after external fixation Retrospective clinical and radiographic assessment

Directory of Open Access Journals (Sweden)

Al. Șerban

2014-02-01

Full Text Available Fractures of the horizontal surface of the distal tibia are known commonly as pylon or plafond fractures, and represent 1-5% of lower extremity fractures, 7-10% of all tibial fractures. The protocol consisted of immediate (within eight to 24 hours open reduction and internal fixation of the fibula, using a fibular plate or one third tubular plate and application of an external fixator spanning the ankle joint. In the second stage, the treatment of proximal and distal tibial fractures with close reduction and MIPPO technique can preserve soft tissue, simplify operative procedure and decrease wound, obtain rigid internal fixation and guarantee early function exercises of ankle joint. In this study we evaluated 22 patients treated in Clinical Emergency Hospital Constanta between April 2012 - July 2013 diagnosed with multifragmentary fractures of the distal tibia. This study evaluates the treatment of complex fractures of distal tibia with locked plate after external fixation. There were 17 males and 5 females of mean age 51,7 years (31-68. The mean follow-up period was 14 weeks. (Ranging from 9-16 weeks. All patients were fully weight bearing at 16 weeks (ranging 9-16 weeks showing radiological union. There were no cases of failures of fixation, or rotational misalignment. No significant complication was observed in our patients. MIPO is an effective method of treatment for distal tibial fractures, reduce surgical trauma and maintain a more biologically favorable environment for fracture healing, reducing risks of infection and nonunion.

[Surgical treatment for talar neck fracture of Hawkins III, IV type with compression hollow screws combined with external fixator].

Science.gov (United States)

Wang, Xian-Xun; Wan, Chang-Tao; Yu, Li

2017-05-25

To investigate the clinical effects of compression hollow screws combined with external fixator in treating talar neck fracture of Hawkins III, IV type. From March 2010 to August 2014, 15 patients with talar neck fractures of Hawkins III, IV type were treated by open reduction and compression hollow screws fixation complicated with external fixator fixation. Including 9 males and 6 females, aged from 17 to 65 years old with an average of 37.5 years old. There were 9 cases of Hawkins III and 6 cases of Hawkins IV type. Postoperative radiographs and CT of ankle were used to evaluate the fracture healing and talar necrosis. The function of ankle and foot were evaluated by American Society of Ankle and Foot Surgery(AOFAS). All the patients were followed up for 8 to 55 months with an average of 23.5 months and all fractures got bone healing from 13 to 38 weeks with an average of (17.99±6.81) weeks. Traumatic arthritis occurred in 7 cases and talar necrosis in 6 cases (2 cases of type III and 4 cases of type IV) after operation. The average AOFAS score was 61.80±18.75, including excellent in 4 cases, good in 2 cases, fair in 4 cases and poor in 5 cases. Talar neck fracture with Hawkins III, IV type has large possibility to develop avascular necrosis. Hollow compression screw combined with external fixation may late weight-bearing for ankle and can sufficiently guarantee bone healing time, and achieve good results for the treatment of talar neck fracture.

No Higher Risk of CRPS After External Fixation of Distal Radial Fractures - Subgroup Analysis Under Randomised Vitamin C Prophylaxis.

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Zollinger, Paul E; Kreis, Robert W; van der Meulen, Hub G; van der Elst, Maarten; Breederveld, Roelf S; Tuinebreijer, Wim E

2010-02-17

Operative and conservative treatment of wrist fractures might lead to complex regional pain syndrome (CRPS) type I.In our multicenter dose response study in which patients with distal radial fractures were randomly allocated to placebo or vitamin C in a daily dose of 200mg, 500mg or 1500mg during 50 days, an operated subgroup was analyzed.48 (of 427) fractures) were operated (11.2%). Twenty-nine patients (60%) were treated with external fixation, 14 patients (29%) with K-wiring according to Kapandji and five patients (10%) with internal plate fixation. The 379 remaining patients were treated with a plaster.In the operated group of patients who received vitamin C no CRPS (0/37) was seen in comparison with one case of CRPS (Kapandji technique) in the operated group who received placebo (1/11 = 9%, p=.23). There was no CRPS after external fixation.In the conservatively treated group 17 cases of CRPS (17/379 = 4.5%) occurred in comparison with one in case of CRPS in the operated group (1/48 = 2.1%, p=.71).External fixation doesn't necessarily lead to a higher incidence of CRPS in distal radial fractures. Vitamin C may also play a role in this. This subgroup analysis in operated distal radial fractures showed no CRPS occurrence with vitamin C prophylaxis.

Good Functional Recovery of Complex Elbow Dislocations Treated With Hinged External Fixation: A Multicenter Prospective Study

NARCIS (Netherlands)

G.I.T. Iordens (Gijs); D. den Hartog (Dennis); E.M.M. van Lieshout (Esther); W.E. Tuinebreijer (Wim); J. de Haan (Jeroen); P. Patka (Peter); M.H.J. Verhofstad (Michiel); N.W.L. Schep (Niels)

2015-01-01

textabstractBackground: After a complex dislocation, some elbows remain unstable after closed reduction or fracture treatment. Function after treatment with a hinged external fixator theoretically allows collateral ligaments to heal without surgical reconstruction. However, there is a lack of

A randomised prospective study of two different combined internal and external fixation techniques for distal tibia shaft fractures.

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Sun, Liao-Jun; Yu, Xian-Bin; Dai, Cheng-Qian; Hu, Wei; Guo, Xiao-Shan; Chen, Hua

2014-12-01

External fixation combined with limited open reduction and internal fixation (EF + LORIF) is a well-accepted and effective method for distal tibia shaft fractures, but it was also related to complications. The objective of this study was to compare external fixation combined with closed reduction and internal fixation (EF + CRIF) with EF + LORIF in the treatment of distal tibia shaft fractures, and explore the benefits and defects of these two techniques. Fifty-six patients were randomised to operative stabilisation either by an external fixator combined with two closed titanium elastic nails or by external fixation combined with limited open reduction and internal fixation. Pre-operative variables included the patients’ age, sex, the affected side, cause of injury, Tscherne classification of soft tissue injury, fracture pattern, and time from injury to surgery. Peri-operative variables were the operating time and the radiation time. Postoperative variables were wound problems and other complications, union time, time of recovery to work, the functional American Orthopaedic Foot and Ankle surgery (AOFAS) score. There was no significant difference in the mean operating time (72.6 ± 11.5 vs. 78.5 ± 16.4 min, P = 0.125), the time to union (21.2 ± 11.0 vs. 22.5 ± 12.3 weeks, P = 0.678), the time of recovery to work (25.0 ± 14.5 vs. 26.4 ± 13.6 weeks, P = 0.711), pin track infection (3/28 vs. 4/28, P = 1.000), delayed union (2/28 vs. 3/28, P = 1.000), pain (38.3 ± 1.6 vs. 38.7 ± 1.5, P = 0.339), function (44.4 ± 6.0 vs. 45.0 ± 5.5, P = 0.698), and total AOFAS scores (91.5 ± 7.4 vs. 93.4 ± 6.8, P = 0.322) between the two groups. However, the mean radiation time was longer in the EF + CRIF group than in the EF + LORIF group (2.0 ± 1.2 vs. 0.3 ± 0.1 min, P alignment was obtained in 50 patients (22 in EF + CRIF vs. 28 in EF + LORIF, P = 0.023). Two cases with EF + CRIF had a 6 degrees of recurvatum deformity and four had 6–9 degrees of valgus deformity

Good Functional Recovery of Complex Elbow Dislocations Treated With Hinged External Fixation: A Multicenter Prospective Study

NARCIS (Netherlands)

Iordens, Gijs I. T.; den Hartog, Dennis; van Lieshout, Esther M. M.; Tuinebreijer, Wim E.; de Haan, Jeroen; Patka, Peter; Verhofstad, Michael H. J.; Schep, Niels W. L.; Bronkhorst, M. W. G. A.; de Vries, M. R.; Goslings, J. C.; Rhemrev, S. J.; Roukema, G. R.; van der Meulen, H. G. W. M.; Verleisdonk, E. J. M. M.; Vroemen, J. P. A. M.; Wittich, Ph

2015-01-01

After a complex dislocation, some elbows remain unstable after closed reduction or fracture treatment. Function after treatment with a hinged external fixator theoretically allows collateral ligaments to heal without surgical reconstruction. However, there is a lack of prospective studies that

[Case control study on therapeutic effects of dynamic external fixtor combined with limited internal fixation and cross K-wires fixation for the treatment of Pilon fractures of the proximal interphalangeal joint].

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Miao, Dao-yi; Yang, Guo-jing; Zhang, Ling-zhou; Wu, Jian-wei

2015-10-01

To compare the clinical effects and safety of dynamic external fixtor combined with limited internal fixation and cross K-wires fixation for the treatment of close Pilon fractures of the proximal interphalangeal joint. From June 2012 to June 2014, totally 41 patients (45 fingers) with close interphalangeal joint Pilon fracture were treated by dynamic external fixtor combined with limited internal fixation or cross K-wires fixation, and all the patients were followed up. In the dynamic external fixtor combined with limited internal fixation group (group A), there were 21 patients with 22 fingers, including 12 males and 9 females, with an average of (30.6±5.6) years old. In the cross K-wires fixation group (group B), there were 20 patients with 23 fingers, including 11 males and 9 females, with an average of (30.1±5.3) years old. Regular re-examination of X-ray was performed to evaluate the active range of joint motion, fracture healing time, infection rate and postoperative joint motion pain. According to the evaluation criteria of upper extremity function issued by the Hand Surgery Society of Chinese Medical Association, the excellent and good cases of group A was up to 19 and 13 for group B. The evaluation results has significant differences (Z=2.558, P=0.011). The excellent and good rate of group A was obviously higher than that of group B. The average bone union time of group A was (7.9±2.1) weeks, and (8.1±2.3) weeks for group B. There was no significant difference on the mean healing time (t=-0.304, P=0.762). The infection fingers of group A was 5, and 1 for group B. The difference between the results was statistically significant (χ2=3.287, Pexternal fixtor combined with limited internal fixation is a reliable and effective method to treat Pilon fractures of the proximal interphalangeal joint. It allows early postoperative functional rehabilitation and restores the joint function.

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...

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

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

2016-02-01

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

Internal versus external fixation of the anterior component in unstable fractures of the pelvic ring: pooled results from a systematic review.

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Wardle, B; Eslick, G D; Sunner, P

2016-10-01

Improving reduction of the pelvic ring improves long-term functional outcomes for patients. It has been demonstrated that posterior internal fixation is necessary to adequately control fractures to the posterior ring and there is evidence that supplementing this with fixation of the anterior ring improves stability. It is accepted that internal fixation provides greater stability than external fixation of the anterior ring but long-term differences in radiographic and functional outcomes have not yet been quantified. A search of electronic databases, reference lists and review articles from 1989 to 2015 yielded 18 studies (n = 884) that met our inclusion criteria. We included studies that discussed pelvic ring injuries in adults, reported functional or radiological outcomes or complications by anterior ring intervention and exceeded 14 patients. We excluded biomechanical and cadaver studies. Internal fixation of the anterior pelvic ring had better functional and radiographic outcomes. Residual displacement of >10 mm was less common with internal fixation (ER 0.12, 95 % CI 0.06-0.24) than external fixation (ER 0.31, 95 % CI 0.11-0.62). Unsatisfactory outcomes also occurred at a lower rate (ER 0.09, 95 % CI 0.03-0.22) compared to external fixation (ER 0.32, 95 % CI 0.18-0.50). Losses of reduction (ER 0.02, 95 % CI 0.01-0.04 versus ER 0.07, 95 % CI 0.02-0.21), malunions (ER 0.03, 95 % CI 0.01-0.08 versus ER 0.07, 95 % CI 0.02-0.21) and delayed/non-unions (ER 0.02, 95 % CI 0.01-0.05 versus ER 0.04, 95 % CI 0.02-0.07). Internal fixation of the anterior pelvic ring as supplementary fixation for unstable injuries to the pelvic ring appears to result in better radiographic and functional outcomes as well as fewer complications. However, data that separated outcomes and complications in relation to interventions of the anterior pelvic ring were limited. More studies looking specifically at outcomes in relation to the type of anterior ring intervention are

Postoperative complications associated with external skeletal fixators in cats.

Science.gov (United States)

Beever, Lee; Giles, Kirsty; Meeson, Richard

2017-07-01

The objective of this study was to quantify complications associated with external skeletal fixators (ESFs) in cats and to identify potential risk factors. A retrospective review of medical records and radiographs following ESF placement was performed. Case records of 140 cats were reviewed; fixator-associated complications (FACs) occurred in 19% of cats. The region of ESF placement was significantly associated with complication development. Complications developed most frequently in the femur (50%), tarsus (35%) and radius/ulna (33%). Superficial pin tract infection (SPTI) and implant failure accounted for 45% and 41% of all FACs, respectively. SPTI occurred more frequently in the femur, humerus and tibia, with implant failure more frequent in the tarsus. No association between breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, degree of fracture load sharing, and the incidence or type of FAC was identified. No association between region of placement, breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, fracture load sharing and the time to complication development was identified. Complication development is not uncommon in cats following ESF placement. The higher complication rate in the femur, tarsus and radius/ulna should be considered when reviewing options for fracture management. However, cats appear to have a lower rate of pin tract infections than dogs.

Correction of axial deformity during lengthening in fibular hypoplasia: Hexapodal versus monorail external fixation.

Science.gov (United States)

Chalopin, A; Geffroy, L; Pesenti, S; Hamel, A; Launay, F

2017-09-01

Childhood fibular hypoplasia is a rare pathology which may or may not involve limb-length discrepancy and axial deformity in one or more dimensions. The objective of the present study was to compare the quality of the axial correction achieved in lengthening procedures by hexapodal versus monorail external fixators. The hypothesis was that the hexapodal fixator provides more precise correction. A retrospective multicenter study included 52 children with fibular hypoplasia. Seventy-two tibias were analyzed, in 2 groups: 52 using a hexapodal fixator, and 20 using a monorail fixator. Mean age was 10.2 years. Mean lengthening was 5.7cm. Deformities were analyzed and measured in 3 dimensions and classified in 4 preoperative types and 4 post-lengthening types according to residual deformity. Complete correction was achieved in 26 tibias in the hexapodal group (50%) and 2 tibias in the monorail group (10%). Mean post-correction mechanical axis deviation was smaller in the hexapodal group: 12.83mm, versus 14.29mm in the monorail group. Mean post-correction mechanical lateral distal femoral angle was 87.5° in the hexapodal group, versus 84.3° in the monorail group (P=0.002), and mean mechanical medial proximal tibial angle 86.9° versus 89.5°, respectively (P=0.015). No previous studies focused on this congenital pathology in lengthening and axial correction programs for childhood lower-limb deformity. The present study found the hexapodal fixator to be more effective in conserving or restoring mechanical axes during progressive bone lengthening for fibular hypoplasia. The hexapodal fixator met the requirements of limb-length equalization in childhood congenital lower-limb hypoplasia, providing better axial correction than the monorail fixator. IV. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Treatment of unstable intraarticular fracture of distal radius: POP casting with external fixation.

Science.gov (United States)

ur Rahman, Obaid; Khan, Mohammad Qadeem; Rasheed, Haroon; Ahmad, Saleem

2012-04-01

To compare radiological and functional outcome of external fixation and distraction with conservative Plaster of Paris (POP) cast for unstable intra-articular fractures of the distal radius. The study was conducted on 60 patients with unstable intra-articular fracture of distal radius who reported to emergency or outpatient Orthopaedic Surgery department of Benazir Bhutto Hospital, Rawalpindi, between March and August 2007. They were divided into two equal groups: Group A and Group B, treated by Plaster of Paris cast, and external fixation with distraction respectively. The functional outcome in terms of freedom from pain, range of movement, grip power and deformity, and the radiological outcome of radial length, incongruity and radio-ulnar joint position were analysed at three months follow-up using a 3-point scoring scale. In Group A, 1 (3%) patient showed excellent result, 8 (27%) patients good results, 19 (63%) patients fair results and 2 (7%) patients poor result. In Group B, 14 (47%) patients showed excellent results, 11 (37%) patients good results, 4 (13%) patients fair results and 1 (3%) patient poor result. The outcome score of the Group B patients was significantly better compared to the Group A patients (p value advantages over conventional Plaster of Paris cast in the treatment of unstable intra-articular fractures of distal radius.

Management of tibial fractures using a circular external fixator in two calves.

Science.gov (United States)

Aithal, Hari Prasad; Kinjavdekar, Prakash; Amarpal; Pawde, Abhijit Motiram; Singh, Gaj Raj; Setia, Harish Chandra

2010-07-01

To report the repair of tibial diaphyseal fractures in 2 calves using a circular external skeletal fixator (CEF). Clinical report. Crossbred calves (n=2; age: 6 months; weight: 55 and 60 kg). Mid-diaphyseal tibial fractures were repaired by the use of a 4-ring CEF (made of aluminum rings with 2 mm K-wires) alone in 1 calf and in combination with hemicerclage wiring in 1 calf. Both calves had good weight bearing with moderate lameness postoperatively. Fracture healing occurred by day 60 in 1 calf and by day 30 in calf 2. The CEF was well maintained and tolerated by both calves through fracture healing. Joint mobility and limb usage improved gradually after CEF removal. CEF provided a stable fixation of tibial fractures and healing within 60 days and functional recovery within 90 days. CEF can be safely and successfully used for the management of selected tibial fractures in calves.

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.

Improving tribological and anti-bacterial properties of titanium external fixation pins through surface ceramic conversion.

Science.gov (United States)

Dong, Huan; Mukinay, Tatiana; Li, Maojun; Hood, Richard; Soo, Sein Leung; Cockshott, Simon; Sammons, Rachel; Li, Xiaoying

2017-01-01

In this study, an advanced ceramic conversion surface engineering technology has been applied for the first time to self-drilling Ti6Al4V external fixation pins to improve their performance in terms of biomechanical, bio-tribological and antibacterial properties. Systematic characterisation of the ceramic conversion treated Ti pins was carried out using Scanning electron microscope, X-ray diffraction, Glow-discharge optical emission spectroscopy, nano- and micro-indentation and scratching; the biomechanical and bio-tribological properties of the surface engineered Ti pins were evaluated by insertion into high density bone simulation material; and the antibacterial behaviour was assessed with Staphylococcus aureus NCTC 6571. The experimental results have demonstrated that the surfaces of Ti6Al4V external fixation pins were successfully converted into a TiO 2 rutile layer (~2 μm in thickness) supported by an oxygen hardened case (~15 μm in thickness) with very good bonding due to the in-situ conversion nature. The maximum insertion force and temperature were reduced from 192N and 31.2 °C when using the untreated pins to 182N and 26.1 °C when the ceramic conversion treated pins were tested. This is mainly due to the significantly increased hardness (more than three times) and the effectively enhanced wear resistance of the cutting edge of the self-drilling Ti pins following the ceramic conversion treatment. The antibacterial tests also revealed that there was a significantly reduced number of bacteria isolated from the ceramic conversion treated pins compared to the untreated pins of around 50 % after 20 h incubation, P < 0.01 (0.0024). The results reported are encouraging and could pave the way towards high-performance anti-bacterial titanium external fixation pins with reduced pin-track infection and pin loosing.

Objective guidelines for removing an external fixator after tibial lengthening using pixel value ratio: a pilot study.

Science.gov (United States)

Zhao, Li; Fan, Qing; Venkatesh, K P; Park, Man S; Song, Hae Ryong

2009-12-01

During limb lengthening over an intramedullary nail, decisions regarding external fixator removal and weightbearing depend on the amount of callus seen at the lengthening area on radiographs. However, this method is subjective and objective evaluation of the amount of callus likely would minimize nail or interlocking screw breakage and refracture after fixator removal. We asked how many cortices with full corticalization of the newly formed bone at the lengthening area are needed to allow fixator removal and full weightbearing and how to radiographically determine the stage of corticalization. We retrospectively reviewed 17 patients (34 lengthenings) who underwent bilateral tibial lengthenings over an intramedullary nail. The average gain in length was 7.2 +/- 3.4 cm. We determined the pixel value ratio (ratio of pixel value of regenerate versus the mean pixel value of adjacent bone) of the lengthened area on radiographs. There were no nail or screw breakage and refracture. Partial weightbearing with crutches was permitted when the pixel value ratio was 1 in two cortices and full weightbearing without crutches was permitted when the pixel value ratio was 1 in three cortices. The pixel value ratio on radiographs can be an objective parameter for callus measurement and may provide guidelines for the timing of external fixator removal. We cannot determine from our limited data the minimum pixel value in how many cortices would suggest safe removal, but we can say our criteria were not associated with subsequent refracture.

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

International Nuclear Information System (INIS)

Lischer, C.J.; Fluri, E.; Auer, J.A.

1997-01-01

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

External fixation of the metacarpal fracture with transcortical pins and fiberglass east in Simmental calf

International Nuclear Information System (INIS)

Martins, E.A.N.; Camargo, L.M.

2003-01-01

A six-month-old 245 kg male Simmental calf was referred to the Veterinary Hospital in Cuiabá, MT, with closed comminuted diaphyseal fracture in metacarpus. It was given preference to external fixation as means of fracture immobilization, and transcortical pins and fiberglass cast were used. This technique showed effective immobilization of the fracture, less expensive and feasible to be done in the field [pt

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

NARCIS (Netherlands)

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

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

The Effect of Insertion Technique on Temperatures for Standard and Self-Drilling External Fixation Pins.

Science.gov (United States)

Manoogian, Sarah; Lee, Adam K; Widmaier, James C

2017-08-01

No studies have assessed the effects of parameters associated with insertion temperature in modern self-drilling external fixation pins. The current study assessed how varying the presence of irrigation, insertion speed, and force impacted the insertion temperatures of 2 types of standard and self-drilling external fixation half pins. Seventy tests were conducted with 10 trials for 4 conditions on self-drilling pins, and 3 conditions for standard pins. Each test used a thermocouple inside the pin to measure temperature rise during insertion. Adding irrigation to the standard pin insertion significantly lowered the maximum temperature (P drilling pin tests dropped average rise in temperature from 151.3 ± 21.6°C to 124.1 ± 15.3°C (P = 0.005). When the self-drilling pin insertion was decreased considerably from 360 to 60 rpm, the temperature decreased significantly from 151.3 ± 21.6°C to 109.6 ± 14.0°C (P drilling pin temperature increase was not significant. The standard pin had lower peak temperatures than the self-drilling pin for all conditions. Moreover, slowing down the insertion speed and adding irrigation helped mitigate the temperature increase of both pin types during insertion.

Cost of generating tritium internal and external to a tokamak hybrid reactor

International Nuclear Information System (INIS)

Crotzer, M.E.; Heck, F.M.; Steinke, K.C.

1981-01-01

The costs associated with producing tritium internal and external to a thorium-based tokamak hybrid are estimated for a number of scenarios and the resulting impact on the symbiotic system cost of electricity calculated. For tritium generation within the hybrid, both continuous and batch production is analyzed. For external production, the lithium-bearing blanket is replaced with thorium and the tritium is generated in the client fission reactors. Continuous tritium production within the hybrid is found to increase the cost of electricity from 1.4 to 4.0 mills/kW-h. Batch tritium production can increase the cost of electricity by 10 mills/kW-h. Producing tritium outside the hybrid, and thereby enhancing client support, increases the cost of electricity from 1.8 to 4.1 mills/kW-h

Successful correction of tibial bone deformity through multiple surgical procedures, liquid nitrogen-pretreated bone tumor autograft, three-dimensional external fixation, and internal fixation in a patient with primary osteosarcoma: a case report.

Science.gov (United States)

Takeuchi, Akihiko; Yamamoto, Norio; Shirai, Toshiharu; Nishida, Hideji; Hayashi, Katsuhiro; Watanabe, Koji; Miwa, Shinji; Tsuchiya, Hiroyuki

2015-12-07

In a previous report, we described a method of reconstruction using tumor-bearing autograft treated by liquid nitrogen for malignant bone tumor. Here we present the first case of bone deformity correction following a tumor-bearing frozen autograft via three-dimensional computerized reconstruction after multiple surgeries. A 16-year-old female student presented with pain in the left lower leg and was diagnosed with a low-grade central tibial osteosarcoma. Surgical bone reconstruction was performed using a tumor-bearing frozen autograft. Bone union was achieved at 7 months after the first surgical procedure. However, local tumor recurrence and lung metastases occurred 2 years later, at which time a second surgical procedure was performed. Five years later, the patient developed a 19° varus deformity and underwent a third surgical procedure, during which an osteotomy was performed using the Taylor Spatial Frame three-dimensional external fixation technique. A fourth corrective surgical procedure was performed in which internal fixation was achieved with a locking plate. Two years later, and 10 years after the initial diagnosis of tibial osteosarcoma, the bone deformity was completely corrected, and the patient's limb function was good. We present the first report in which a bone deformity due to a primary osteosarcoma was corrected using a tumor-bearing frozen autograft, followed by multiple corrective surgical procedures that included osteotomy, three-dimensional external fixation, and internal fixation.

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.

Partial calcanectomy and Ilizarov external fixation may reduce amputation need in severe diabetic calcaneal ulcers.

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Akkurt, Mehmet Orçun; Demirkale, Ismail; Öznur, Ali

2017-01-01

Objective : The treatment of diabetic hindfoot ulcers is a challenging problem. In addition to serial surgical debridements, hyperbaric oxygen therapy and local wound care play important roles in the surgeon's armamentarium, for both superficial infection and gangrene of the soft tissue, often complicated by osteomyelitis of the calcaneus. The purpose of this study was to evaluate the results of an aggressive approach from diagnosis to treatment of calcaneal osteomyelitis in foot-threatening diabetic calcaneal ulcers. Methods : The study included 23 patients with diabetic hindfoot ulcers who were treated with radical excision of the necrotic tissue and application of circular external fixation. The treatment protocol was a combination of magnetic resonance imaging (MRI)-guided debridement of the necrotic tissues and application of an Ilizarov external fixator in plantarflexion to decrease the soft-tissue defect. Primary outcome measures were total cure of infection and obvious healing of the osteomyelitis at 12 weeks determined by MRI, and clinical cure through objective assessment of the appearance of the wound. Results : The wounds healed in 18 of the 23 patients (78%), partial recovery occurred and subsequent flap operation was performed in three patients (13%), and below-the-knee amputation was performed in two patients (9%). Conclusions : This surgical protocol is effective in ameliorating diabetic hindfoot ulcers with concomitant calcaneal osteomyelitis, and satisfactorily reduces the need for amputation.

Preliminary experience with biodegradable implants for fracture fixation

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Dhillon Mandeep

2008-01-01

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

Chronic elbow dislocation: a rare complication of tennis elbow surgery. Successful treatment by open reduction and external fixator.

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Degreef, I; De Smet, L

2007-06-01

A case is presented of chronic dislocation of the elbow after tennis elbow surgery combined with posterior interosseous nerve (PIN) release. An open reduction with repair of the collateral ligaments was performed. Postoperative rehabilitation involved the use of an articulated external fixator and there was a successful outcome. Possible causes of the dislocation are discussed.

Ingenious method of external fixator use to maintain alignment for nailing a proximal tibial shaft fracture.

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Behera, Prateek; Aggarwal, Sameer; Kumar, Vishal; Kumar Meena, Umesh; Saibaba, Balaji

2015-09-01

Fractures of the tibia are one of the most commonly seen orthopedic injuries. Most of them result from a high velocity trauma. While intramedullary nailing of tibial diaphyseal fractures is considered as the golden standard form of treatment for such cases, many metaphyseal and metaphyseal-diaphyseal junction fractures can also be managed by nailing. Maintenance of alignment of such fractures during surgical procedure is often challenging as the pull of patellar tendon tends to extend the proximal fragment as soon as one flexes the knee for the surgical procedure. Numerous technical modifications have been described in the literature for successfully nailing such fractures including semi extended nailing, use of medial plates and external fixators among others. In this study, it was aimed to report two cases in which we used our ingenious method of applying external fixator for maintaining alignment of the fracture and aiding in the entire process of closed intramedullary nailing of metaphyseal tibial fractures by the conventional method. We were able to get good alignment during and after the closed surgery as observed on post-operative radiographs and believe that further evaluation of this technique may be of help to surgeons who want to avoid other techniques.

Humeral repair in birds by guided tissue regeneration and external and internal associated fixation techniques

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Delogu, M.

1993-01-01

Ten pigeons (Columba livia domestic form) with humeral diaphyseal fracture were treated with external and internal fixation techniques (Boston technique and intamedullary pin). Longitudinal space was intentionally left between fracture surfaces during osteosynthesis. This space was filled with bovine lyophilized collagen, set around an intramedullary pin, in five samples. Ossification process was checked by radiography every seven days. Results show the utility of this technique in pneumatic bird bones. In fact, shortening control and callus formation facility were observed [it

Incidence of infection after early intramedullary nailing of open tibial shaft fractures stabilized with pinless external fixators

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Kulshrestha Vikas

2008-01-01

Full Text Available Background: A major drawback of conventional fixator system is the penetration of fixator pins into the medullary canal. The pins create a direct link between the medullary cavity and outer environment, leading to higher infection rates on conversion to intramedullary nailing. This disadvantage is overcome by the AO pinless fixator, in which the trocar points are clamped onto the outer cortex without penetrating it. This study was designed to evaluate the role of AO pinless fixators in primary stabilization of open diaphyseal tibial fractures that received staged treatment because of delayed presentation or poor general condition. We also analyzed the rate of infection on early conversion to intramedullary nail. Materials and Methods: This study is a retrospective review of 30 open diaphyseal fractures of tibia, which were managed with primary stabilization with pinless fixator and early exchange nailing. Outcome was evaluated in terms of fracture union and rate of residual infection. The data were compared with that available in the literature. Results: All the cases were followed up for a period of 2 years. The study includes Gustilo type 1 (n=10, 14 Gustilo type 2 (n=14, and type3 (n=6 cases. 6 cases (20% had clamp site infection, 2 cases (6.7% had deep infection, and in 28 cases (93% the fracture healed and consolidated well. Conclusion: This study has highlighted the valuable role of pinless external fixator in the management of open tibial fractures in terms of safety and ease of application as well as the advantage of early conversion to intramedullary implant without the risk of deep infection.

Combined circular external fixation and open reduction internal fixation with pro-syndesmotic screws for repair of a diabetic ankle fracture

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Zacharia Facaros

2010-10-01

Full Text Available The surgical management of ankle fractures among the diabetic population is associated with higher complication rates compared to the general population. Efforts toward development of better methods in prevention and treatment are continuously evolving for these injuries. The presence of peripheral neuropathy and the possible development of Charcot neuroarthropathy in this high risk patient population have stimulated much surgical interest to create more stable osseous constructs when open reduction of an ankle fracture/dislocation is required. The utilization of multiple syndesmotic screws (pro-syndesmotic screws to further stabilize the ankle mortise has been reported by many foot and ankle surgeons. In addition, transarticular Steinmann pins have been described as an adjunct to traditional open reduction with internal fixation (ORIF of the ankle to better stabilize the talus, thus minimizing risk of further displacement, malunion, and Charcot neuroarthropathy. The authors present a unique technique of ORIF with pro-syndesmotic screws and the application of a multi-plane circular external fixator for management of a neglected diabetic ankle fracture that prevented further deformity while allowing a weight-bearing status. This technique may be utilized for the management of complex diabetic ankle fractures that are prone to future complications and possible limb loss.

Minimally invasive surgical technique: Percutaneous external fixation combined with titanium elastic nails for selective treatment of tibial fractures.

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Tu, Kai-Kai; Zhou, Xian-Ting; Tao, Zhou-Shan; Chen, Wei-Kai; Huang, Zheng-Liang; Sun, Tao; Zhou, Qiang; Yang, Lei

2015-12-01

Several techniques have been described to treat tibial fractures, which respectively remains defects. This article presents a novel intra- and extramedullary fixation technique: percutaneous external fixator combined with titanium elastic nails (EF-TENs system). The purpose of this study is to introduce this new minimally invasive surgical technique and selective treatment of tibial fractures, particularly in segmental fractures, diaphysis fractures accompanied with distal or proximal bone subfissure, or fractures with poor soft-tissue problems. Following ethical approval, thirty-two patients with tibial fractures were treated by the EF-TENs system between January 2010 and December 2012. The follow-up studies included clinical and radiographic examinations. All relevant outcomes were recorded during follow-up. All thirty-two patients were achieved follow-ups. According to the AO classification, 3 Type A, 9 Type B and 20 Type C fractures were included respectively. According to the Anderson-Gustilo classification, there were 5 Type Grade II, 3 Type Grade IIIA and 2 Type Grade IIIB. Among 32 patients, 8 of them were segmental fractures. 12 fractures accompanied with bone subfissure. Results showed no nonunion case, with an average time of 23.7 weeks (range, 14-32 weeks). Among them, there were 3/32 delayed union patients and 0/32 malunion case. 4/32 patients developed a pin track infection and no patient suffered deep infection. The external fixator was removed with a mean time of 16.7 weeks (range, 10-26 weeks). Moreover, only 1/32 patient suffered with the restricted ROM of ankle, none with the restricted ROM of knee. This preliminary study indicated that the EF-TENs system, as a novel intra- and extramedullary fixation technique, had substantial effects on selective treatment of tibial fractures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Percutaneous external fixator pins with bactericidal micron-thin sol-gel films for the prevention of pin tract infection.

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Qu, Haibo; Knabe, Christine; Radin, Shula; Garino, Jonathan; Ducheyne, Paul

2015-09-01

Risk of infection is considerable in open fractures, especially when fracture fixation devices are used to stabilize the fractured bones. Overall deep infection rates of 16.2% have been reported. The infection rate is even greater, up to 32.2%, with external fixation of femoral fractures. The use of percutaneous implants for certain clinical applications, such as percutaneous implants for external fracture fixation, still represents a challenge today. Currently, bone infections are very difficult to treat. Very potent antibiotics are needed, which creates the risk of irreversible damage to other organs, when the antibiotics are administered systemically. As such, controlled, local release is being pursued, but no such treatments are in clinical use. Herein, the use of bactericidal micron-thin sol-gel films on metallic fracture fixation pins is reported. The data demonstrates that triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether), an antimicrobial agent, can be successfully incorporated into micron-thin sol-gel films deposited on percutaneous pins. The sol-gel films continuously release triclosan in vitro for durations exceeding 8 weeks (longest measured time point). The bactericidal effect of the micron-thin sol-gel films follows from both in vitro and in vivo studies. Inserting percutaneous pins in distal rabbit tibiae, there were no signs of infection around implants coated with a micron-thin sol-gel/triclosan film. Healing had progressed normally, bone tissue growth was normal and there was no epithelial downgrowth. This result was in contrast with the results in rabbits that received control, uncoated percutaneous pins, in which abundant signs of infection and epithelial downgrowth were observed. Thus, well-adherent, micron-thin sol-gel films laden with a bactericidal molecule successfully prevented pin tract infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of an external readout electronics for a hybrid photon detector

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Uyttenhove, Simon; Tichon, Jacques; Garcia, Salvador

The pixel hybrid photon detectors currently installed in the LHCb Cherenkov system encapsulate readout electronics in the vacuum tube envelope. The LHCb upgrade and the new trigger system will require their replacement with new photon detectors. The baseline photon detector candidate is the multi-anode photomultiplier. A hybrid photon detector with external readout electronics has been proposed as a backup option. This master thesis covers a R & D phase to investigate this latter concept. Extensive studies of the initial electronics system underlined the noise contributions from the Beetle chip used as front-end readout ASIC and from the ceramic carrier of the photon detector. New front-end electronic boards have been developed and made fully compatible with the existing LHCb-RICH infrastructure. With this compact readout system, Cherenkov photons have been successfully detected in a real particle beam environment. The proof-of-concept of a hybrid photon detector with external readout electronics was val...

The use of twin-ring Ilizarov external fixator constructs: application and biomechanical proof-of principle with possible clinical indications

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Magnissalis Evangelos A

2011-08-01

Full Text Available Abstract Background In peri- or intra-articular fractures of the tibia or femur, the presence of short metaphyseal bone fragments may make the application of an Ilizarov external fixator (IEF challenging. In such cases, it may be necessary to bridge the adjacent joint in order to ensure stable fixation. The twin-ring (TR module of circular external fixation is proposed as an alternative method that avoids joint bridging, without compromising stability of fixation. The aim of this study is to present the experimental tests performed to compare the biomechanical characteristics of the single- and TR IEF modules. The clinical application of the TR module in select patients is also presented and the merits of this technique are discussed. Methods In this experimental study, the passive stiffness and stability of the single-ring (SR and twin-ring (TR IEF modules were tested under axial and shear loading conditions. In each module, two perpendicular wires on the upper surface and another two wires on the lower surface of the rings were used for fixation of the rings on plastic acetal cylinders simulating long bones. Results In axial loading, the main outcome measure was stiffness and the SR module proved stiffer than the TR. In shear loading, the main outcome measure was stability, the TR module proving more stable than the SR. Discussion The TR configuration, being stiffer in shear loading, may make joint bridging unnecessary when an IEF is applied. If it is still required, TR frames allow for an earlier discontinuation of bridging; either case is in favour of a successful final outcome. Conclusion The application of the TR module has led to satisfactory clinical outcomes and should be considered as an alternative in select trauma patients treated with an IEF. Biomechanically, the TR module possesses features which enhance fracture healing and at the same time obviate the need for bridging adjacent joints, thereby significantly reducing patient

Management of simple (types A and B) closed tibial shaft fractures using percutaneous lag-screw fixation and Ilizarov external fixation in adults.

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El-Sayed, Mohamed; Atef, Ashraf

2012-10-01

Although intramedullary fixation of closed simple (type A or B) diaphyseal tibial fractures in adults is well tolerated by patients, providing lower morbidity rates and better mobility, it is associated with some complications. This study evaluated the results of managing these fractures using percutaneous minimal internal fixation using one or more lag screws, and Ilizarov external fixation. This method was tested to evaluate its efficacy in immediate weight bearing, fracture healing and prevention of any post-immobilisation stiffness of the ankle and knee joints. This randomised blinded study was performed at a referral, academically supervised, level III trauma centre. Three hundred and twenty-four of the initial 351 patients completed this study and were followed up for a minimum of 12 (12-88) months. Patient ages ranged from 20 to 51 years, with a mean of 39 years. Ankle and knee movements and full weight bearing were encouraged immediately postoperatively. Solid union was assessed clinically and radiographically. Active and passive ankle and knee ranges of motion were measured and compared with the normal side using the Wilcoxon signed rank test for matched pairs. Subjective Olerud and Molander Ankle Score was used to detect any ankle joint symptoms at the final follow-up. No patient showed delayed or nonunion. All fractures healed within 95-129 days. Based on final clinical and radiographic outcomes, this technique proves to be adequate for managing simple diaphyseal tibial fractures. On the other hand, it is relatively expensive, technically demanding, necessitates exposure to radiation and patients are expected to be frame friendly.

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

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

2014-07-01

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

Biomechanical study in vitro on the use of self-designed external fixator in diaphyseal III metacarpal fractures in horses.

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Turek, B; Potyński, A; Wajler, C; Szara, T; Czopowicz, M; Drewnowska, O

2015-01-01

Diaphyseal fractures of the III metacarpal bone represent 22% of all fractures of the long bones in horses. Treatment of such cases is difficult. The most popular solution used in these types of fractures is two plates applied directly to the bone surface, but they are not applicable on contaminated and infected fractures. External fixators are quite commonly used in human medicine, although in veterinary practice there is no typical stabilizer designed for the treatment of diaphyseal fractures of the III metacarpal bone so far. In this study, an external semicircular fixator of our own design was used and in vitro strength tests were conducted to determine the maximum force which would lead to the destruction of non-fractured bone and fractured bone treated with the stabilizer. On the basis of the strength tests, we can conclude that the stabilizer can be strong enough to allow the horse to stand up after surgery. It also has many favorable features which make it easy to assemble and to take care of a wound, while being safe enough for the animal at the same time.

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

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

2009-12-01

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

Combination of Open Subtotal Calcanectomy and Stabilization With External Fixation as Limb Salvage Procedure in Hindfoot-Infected Diabetic Foot Ulcers.

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Dalla Paola, Luca; Carone, Anna; Boscarino, Giulio; Scavone, Giuseppe; Vasilache, Lucian

2016-12-01

Diabetic hindfoot ulcers, complicated by osteomyelitis, are associated with a high risk of major amputation. Partial calcanectomy, preceded by an effective management of the infection and of the eventual peripheral artery disease, can be considered as valid therapeutic option. We have evaluated a therapeutic protocol for diabetic hindfoot ulcers complicated by osteomyelitis, which, besides an adequate surgical debridement, considers a reconstructive pathway assisted by the positioning of a circular external fixator. We made a prospective study of a cohort of diabetic patients affected by heel ulcer complicated by osteomyelitis. All patients underwent open partial calcanectomy associated with the positioning of a circular external frame specifically designed for hindfoot stabilization and offloading. A reconstructive procedure was implemented starting with the application of negative pressure wound therapy and coverage with dermal substitute and split thickness skin grafting. From November 2014 to November 2015, 18 consecutive patients were enrolled. Mean follow-up period was 212.3 ± 64.0 days. Healing was achieved in 18 (100%) patients. The mean healing time was 69.0 ± 64.0 days. No major amputation had to be performed during the follow-up. Open partial calcanectomy associated with external fixation and skin reconstruction was as efficient as limb salvage in patients with infected lesions of the hindfoot complicated by calcaneal osteomyelitis.

Clinical efficacy and safety of limited internal fixation combined with external fixation for Pilon fracture: A systematic review and meta-analysis.

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Zhang, Shao-Bo; Zhang, Yi-Bao; Wang, Sheng-Hong; Zhang, Hua; Liu, Peng; Zhang, Wei; Ma, Jing-Lin; Wang, Jing

2017-04-01

To compare the clinical efficacy and complications of limited internal fixation combined with external fixation (LIFEF) and open reduction and internal fixation (ORIF) in the treatment of Pilon fracture. We searched databases including Pubmed, Embase, Web of science, Cochrane Library and China Biology Medicine disc for the studies comparing clinical efficacy and complications of LIFEF and ORIF in the treatment of Pilon fracture. The clinical efficacy was evaluated by the rate of nonunion, malunion/delayed union and the excellent/good rate assessed by Mazur ankle score. The complications including infections and arthritis symptoms after surgery were also investigated. Nine trials including 498 pilon fractures of 494 patients were identified. The meta-analysis found no significant differences in nonunion rate (RR = 1.60, 95% CI: 0.66 to 3.86, p = 0.30), and the excellent/good rate (RR = 0.95, 95% CI: 0.86 to 1.04, p = 0.28) between LIFEF group and ORIF group. For assessment of infections, there were significant differences in the rate of deep infection (RR = 2.18, 95% CI: 1.34 to 3.55, p = 0.002), and the rate of arthritis (RR = 1.26, 95% CI: 1.03 to 1.53, p = 0.02) between LIFEF group and ORIF group. LIFEF has similar effect as ORIF in the treatment of pilon fractures, however, LIFEF group has significantly higher risk of complications than ORIF group does. So LIFEF is not recommended in the treatment of pilon fracture. Copyright © 2017 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Does hybrid fixation prevent junctional disease after posterior fusion for degenerative lumbar disorders? A minimum 5-year follow-up study.

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Baioni, Andrea; Di Silvestre, Mario; Greggi, Tiziana; Vommaro, Francesco; Lolli, Francesco; Scarale, Antonio

2015-11-01

Medium- to long-term retrospective evaluation of clinical and radiographic outcome in the treatment of degenerative lumbar diseases with hybrid posterior fixation. Thirty patients were included with the mean age of 47.8 years (range 35 to 60 years). All patients underwent posterior lumbar instrumentation using hybrid fixation for lumbar stenosis with instability (13 cases), degenerative spondylolisthesis Meyerding grade I (6 cases), degenerative disc disease of one or more adjacent levels in six cases and mild lumbar degenerative scoliosis in five patients. Clinical outcomes were evaluated using Oswestry disability index (ODI), Roland and Morris disability questionnaire (RMDQ), and the visual analog scale (VAS) pain scores. All patients were assessed by preoperative, postoperative and follow-up standing plain radiographs and lateral X-rays with flexion and extension. Adjacent disc degeneration was also evaluated by magnetic resonance imaging (MRI) at follow-up. At a mean follow-up of 6.1 years, we observed on X-rays and/or MRI 3 cases of adjacent segment disease (10.0 %): two of them (6.6 %) presented symptoms and recurred a new surgery. The last patient (3.3 %) developed asymptomatic retrolisthesis of L3 not requiring revision surgery. The mean preoperative ODI score was 67.6, RMDQ score was 15.1, VAS back pain score was 9.5, and VAS leg pain score was 8.6. Postoperatively, these values improved to 28.1, 5.4, 3.1, and 2.9, respectively, and remained substantially unchanged at the final follow-up: (27.7, 5.2, 2.9, and 2.7, respectively). After 5-year follow-up, hybrid posterior lumbar fixation presented satisfying clinical outcomes in the treatment of degenerative disease.

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

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

2007-04-01

Pin tract infections of external fixators used in orthopaedic reconstructive bone surgery are serious complications that can eventually lead to periostitis and osteomyelitis. In vitro experiments have demonstrated that bacteria adhering to stainless steel in a biofilm mode of growth detach under the influence of small electric currents, while remaining bacteria become less viable upon current application. Therefore, we have investigated whether a 100microA electric current can prevent signs of clinical infection around percutaneous pins, implanted in the tibia of goats. Three pins were inserted into the lateral right tibia of nine goats, of which one served for additional frame support. Two pins were infected with a Staphylococcus epidermidis strain of which one pin was subjected to electric current, while the other pin was used as control. Pin sites were examined daily. The wound electrical resistance decreased with worsening of the infection from a dry condition to a purulent stage. After 21 days, animals were sacrificed and the pins taken out. Infection developed in 89% of the control pin sites, whereas only 11% of the pin sites in the current group showed infection. These results show that infection of percutaneous pin sites of external fixators in reconstructive bone surgery can be prevented by the application of a small DC electric current.

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

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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

Ultrasound-guided supra-acetabular pin placement in pelvic external fixation: description of a surgical technique and results.

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Chana-Rodríguez, Francisco; Cuervas-Mons, Manuel; Rojo-Manaute, José; Mora, Félix; Arnal, Juan; Vaquero-Martín, Javier

2017-11-01

Pelvic fracture in trauma patients can lead to hemodynamic instability. External fixation is a treatment capable of stabilizing these injuries in the context of damage control surgery. Supra-acetabular pin offers the greater biomechanical stability but requires the use of intraoperative fluoroscopy. The aim of this study was to analyze our results for an ultrasound-guided supra-acetabular pinning. Cross-sectional study with cadaveric specimens. Ultrasound-guided pin placement assessed by fluoroscopy and dissection. Fourteen ultrasound-guided supra-acetabular pins were placed in seven cadaveric specimens. Excellent placement in all cases, evaluated with radiological control. Good qualitative bone fixation after dissection. One femoral cutaneous nerve was not found during anatomic dissection and was assumed injured. Ultrasound-guided supra-acetabular pin placement is a feasible and effective technique. Our study indicates that pin placement without intraoperative fluoroscopy is feasible without compromising the reliability of its placement. © 2017 Elsevier Ltd. All rights reserved.

EXPERIMENTAL APPROVAL OF COMBINED FIXATION FOR FEMUR LENGTHENING

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M. A. Stepanov

2017-01-01

Full Text Available Elimination of congenital shortening of lower limb still remains a complex and unsolved orthopaedic task which requires an improved fixation technique as well as adjusted tactics of treatment and rehabilitation procedures.Purpose of the study — experimental approval of femur lengthening technique by external fixation with Ilizarov apparatus and internal fixation by plate.Materials and methods. Femur lengthening was performed in 6 mongrel dogs. Average animal age was 1,5±0,3 years, average weight — 20±5 kg, femur length — 22±2 sm. External apparatus with two supports and a titanium plate of an original design were applied under general anesthesia on the right femur of animals. Lengthening was performed manually at a rate of1 mm per day in 4 stages at a distance of 10% from initial segment length. External apparatus was removed on the last day of distraction after locking the plate. X-ray examination was done on the day of surgery, in 7, 14 and 25 days from the onset of distraction as well as in 14, 30, 60 and 90 days after completion of distraction and removal of external apparatus. Three animals were taken out of experiment in 30 days of fixation, remaining three animals — in 90 days. After euthanasia the authors performed autopsy of the organic femur complex and tissues contacting the plate.Results. The use of operated limb was not restricted during the whole distraction period. The authors observed first roentgenological signs of distraction osteogenesis on 7th day of lengthening. By the end of distraction period, at 25th day, shadows of regenerates demonstrated longitudinal striated structures in all cases. Median lucency area of 1–5 mm was located diagonally and across the regenerate or was intermittent. In 60 days of fixation X-rays demonstrated homogeneous regenerate. External fixation index was 13,9±1,5 days/sm (p≤0,05. The authors observed no cases of implants fracture or deformity during the experiment

Comparison of completely knotless and hybrid double-row fixation systems: a biomechanical study.

Science.gov (United States)

Chu, Thomas; McDonald, Erik; Tufaga, Michael; Kandemir, Utku; Buckley, Jenni; Ma, C Benjamin

2011-04-01

The purpose of this study was to compare the biomechanical performance of a completely knotless double-row repair system (SutureCross Knotless Anatomic Fixation System; KFx Medical, Carlsbad, CA) with 2 commonly used hybrid double-row repair (medial knot-tying, lateral knotless) systems (Bio-Corkscrew/PushLock [Arthrex, Naples, FL] and Spiralok/Versalok [DePuy Mitek, Raynham, MA]). Fourteen pairs of fresh-frozen cadaveric shoulders were harvested, the supraspinatus tendons were isolated, and full-thickness supraspinatus tears were created. One of each pair was repaired with the completely knotless system, and the contralateral side was repaired with either of the hybrid systems. The repairs were then subjected to cyclic loading followed by load to failure. Conditioning elongation, peak-to-peak elongation, ultimate load, and mechanism of failure were recorded and compared by use of paired t tests. Seven additional shoulders were tested to determine the effect of refrigeration storage on the completely knotless system by use of the same mechanical testing protocol. For the completely knotless repair group, 11 of 14 paired specimens failed during the cyclic loading period. Only 1 of 14 hybrid repair systems had failures during cyclic loading, and both hybrid repair systems had statistically lower conditioning elongation than the completely knotless repair group. The mean ultimate load of the SutureCross group was 166 ± 87 N, which was significantly lower than that in the Corkscrew/PushLock (310 ± 82 N) and Spiralok/Versalok (337 ± 44 N) groups. There was an effect of refrigeration storage on the peak-to-peak elongation and stiffness of the SutureCross group; however, there was no difference in ultimate tensile load or conditioning elongation. The completely knotless repair system has lower time-zero biomechanical properties than the other 2 hybrid systems. The SutureCross system has lower time-zero biomechanical properties when compared with other hybrid repair

Operative Fixation Options for Elective and Diabetic Ankle Arthrodesis.

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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.

Radiological landmarks for the safe extra-capsular placement of supra-acetabular half pins for external fixation.

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Lidder, Surjit; Heidari, Nima; Gänsslen, Axel; Grechenig, Wolfgang

2013-03-01

Low anterior external fixators are constructed by placing half pins in the dense bone tunnel of the supra-acetabular region in an anterior to posterior direction. Although the placement of these pins is extra-articular, they may still breach the hip capsule on the anterior inferior iliac spine and thus be intra-capsular. We aim to provide radiological markers for the most superior fibres of the capsule to allow safe extra-capsular pin placement within the supra-acetabular bone tunnel. Thirteen cadaveric pelves were used for this study. The supra-acetabular bone tunnel was visualised with an image intensifier. The proximal most fibres of the hip joint capsule were marked with a K-wire so that their relation to the bone tunnel could be clearly seen on the images. Once all images were acquired they were calibrated and analysed to estimate the dimensions of the supra-acetabular bone tunnel and the reflection of the hip capsule. The median height of the bone tunnel was 23.6 mm (18.9-33.2) and maximum width was 11.4 mm (7.6-16.3). The inferior margin of the bone tunnel was 6.7 mm (1.1-14.5) superior to the acetabular dome, and the most proximal fibres of the capsule were 9.3 mm (4.7-6.1) superior to the acetabular dome. The inferior portion of the tunnel was 3.7 mm (0.3-8.9) within the joint. Half pins for the construction of a pelvic external fixator should be placed in the upper half of the supra-acetabular bone corridor to minimise the risk of intra-capsular placement.

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

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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.

Application of monorail fixator for femoral gap nonunion

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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

Biomechanical effect of interspinous process distraction height after lumbar fixation surgery: An in vitro model.

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Fu, Lin; Ma, Jianxiong; Lu, Bin; Jia, Haobo; Zhao, Jie; Kuang, Mingjie; Feng, Rui; Xu, Liyan; Bai, Haohao; Sun, Lei; Wang, Ying; Ma, Xinlong

2017-07-01

Pedicle screw fixation may induce abnormal activity at adjacent segment and accelerate the degeneration of lumbar vertebrae. Dynamic stabilizers could provide an intermediate solution between conservative treatment and fusion surgery. Lumbar vertebral segment cephalad to instrumented fixation was the most common localization of adjacent segment degeneration. The aim of this study is to explore the use of interspinous process devices in the lumbar vertebral segment cephalad to fixation segment in changing the mechanical distribution and limiting abnormal activity of the spine. Eight specimens were tested in the following groups: intact group, instability group (bilateral facetectomy at L3-L4), fixation group (bilateral facetectomy and pedicle screw fixation at L3-L4), and hybrid fixation group (fixation at L3-L4 and simulating interspinous device implantation of 6, 8, 10, 12, 14, 16, and 18 mm at L2-L3). Range of motion, motion of vertebral body, and strain distribution change were recorded. The range of motion in extension with 16- and 18-mm hybrid constructs was significantly lower than intact, instability, and fixation groups. In flexion and lateral bending, the strain values of L4 inferior articular process with 18-mm hybrid construct have a significant difference compared with other groups. In axial rotation, under the condition of a contralateral state, the strain values of L2 superior articular process with 18-mm hybrid construct have a significant difference compared with intact and fixation groups. The strain value of the L4 inferior articular process had negative correlation with height distraction in three dimensions, except extension. A negative correlation between the strain value of the L2 superior articular process and distraction height was found in contralateral bending and contralateral axial rotation. Interspinous process devices above the fixation segment can change the mechanical distribution of the spine and limit activity in some of the

A new tool fixation for external 3D head tracking using the Polaris Vicra system with the HRRT PET scanner

DEFF Research Database (Denmark)

Olesen, Oline Vinter; Andersen, Flemming; Holm, Søren

-water studies for up to 75 min (3-8 injections) were registered by the Polaris system in 4 volunteers. The tracking tool was fixed. Scans were divided into subframes based on the registered movements and reconstructed using the 3D-OSEM PSF method. The reconstructed subframes were repositioned to a reference......Objectives: The Polaris Vicra system (Northern Digital Inc.) is used for external 3D head registration with the Siemens HRRT brain PET. Our new tool fixation using a standard bandaid with a velcro-strap implies an improved frame repositioning. Methods: Head movements during serial PET 15O...... position and pairwise similarity of subframes was evaluated before and after the repositioning. Results: Registered movements during scans were less than 4.3mm with. Images were compared before/after motion correction. Conclusions: Our new velcro band-aid fixation is suitable for clinical use: easy to use...

Prediction of the neutrons subcritical multiplication using the diffusion hybrid equation with external neutron sources

Energy Technology Data Exchange (ETDEWEB)

Costa da Silva, Adilson; Carvalho da Silva, Fernando [COPPE/UFRJ, Programa de Engenharia Nuclear, Caixa Postal 68509, 21941-914, Rio de Janeiro (Brazil); Senra Martinez, Aquilino, E-mail: aquilino@lmp.ufrj.br [COPPE/UFRJ, Programa de Engenharia Nuclear, Caixa Postal 68509, 21941-914, Rio de Janeiro (Brazil)

2011-07-15

Highlights: > We proposed a new neutron diffusion hybrid equation with external neutron source. > A coarse mesh finite difference method for the adjoint flux and reactivity calculation was developed. > 1/M curve to predict the criticality condition is used. - Abstract: We used the neutron diffusion hybrid equation, in cartesian geometry with external neutron sources to predict the subcritical multiplication of neutrons in a pressurized water reactor, using a 1/M curve to predict the criticality condition. A Coarse Mesh Finite Difference Method was developed for the adjoint flux calculation and to obtain the reactivity values of the reactor. The results obtained were compared with benchmark values in order to validate the methodology presented in this paper.

Prediction of the neutrons subcritical multiplication using the diffusion hybrid equation with external neutron sources

International Nuclear Information System (INIS)

Costa da Silva, Adilson; Carvalho da Silva, Fernando; Senra Martinez, Aquilino

2011-01-01

Highlights: → We proposed a new neutron diffusion hybrid equation with external neutron source. → A coarse mesh finite difference method for the adjoint flux and reactivity calculation was developed. → 1/M curve to predict the criticality condition is used. - Abstract: We used the neutron diffusion hybrid equation, in cartesian geometry with external neutron sources to predict the subcritical multiplication of neutrons in a pressurized water reactor, using a 1/M curve to predict the criticality condition. A Coarse Mesh Finite Difference Method was developed for the adjoint flux calculation and to obtain the reactivity values of the reactor. The results obtained were compared with benchmark values in order to validate the methodology presented in this paper.

Locking plate versus external fixation for type C distal radius fractures: A meta-analysis of randomized controlled trials

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Dong Wang

2018-04-01

Full Text Available Purpose: Distal radial fracture is one of the most common fractures. Up to now, locking plates (LP and external fixation (EF are two conventional surgical approaches to type C radius fracture. Which method is superior has not yet reached a consensus. We try to assess the clinical effectiveness of the two interventions by this meta-analysis. Methods: We used network to search the PubMed, Embase, and Cochrane Medical Library of randomized controlled clinical trials about the type C distal radius fractures performed according to the search strategy mentioned in Cochrane Handbook 5.1.0 from Jan. 2005 to Jan. 2016. Patients in the experimental group were used LP, in the control group were included EF and other surgical approaches. Publication language was restricted to English. Studies that patient population and surgical indication did not define had been excluded. Studies must report at least one of the outcomes as follow: radial inclination, palmar tilt, ulnar variance, range of wrist flexion and extension, and range of wrist supination and pronation. The trials in which participants included children were excluded. We used Jadad study scores to appraise the study. Results: Seven studies included 162 patients (LP group and 190 patients (EF group. We compared the radial inclination, palmar tilt, ulnar variance, range of wrist flexion and extension, and range of wrist supination and pronation. The radial inclination were revealed a difference favoring LP over EF [WMD = 1.84, 95% CI (0.17, 3.50, p = 0.03] and the palmar tilt and ulnar variance was no significant difference between the two groups [(WMD = 3.61, 95% CI (0.00, 7.23, p = 0.05; WMD = 0.05, 95% CI (−0.99, 1.09, p = 0.93]. The functional activities of range of flexion and extension and range of supination and pronation between the two groups was no difference [WMD = 10.04, 95% CI (−6.88, 26.96, p = 0.24; WMD = 12.53, 95% CI (−9.99, 35.06, p = 0.28]. Conclusion

Stiffness Analysis of the Sarafix External Fixator based on Stainless Steel and Composite Material

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Nedim Pervan

2015-11-01

Full Text Available This paper describes a structural analysis of the CAD model three versions fixators Sarafix which is to explore the possibility of introducing composite materials in the construction of the connecting rod fixators comparing values of displacement and stiffness at characteristic structure points. Namely, we have investigated the constructional performance of fixators Sarafix with a connecting rod formed from three different composite materials, the same matrix (epoxy resin with three different types of fibers (E glass, kevlar 49 and carbonM55J. The results of the structural analysis fixators Sarafix with a connecting rod made of composite materials are compared with the results of tubular connecting rod fixators made of stainless steel. After comparing the results, from the aspect of stiffness, we gave the final considerations about composite material which provides an adequate substitution for the existing material.

Elevated CO2 concentration around alfalfa nodules increases N2 fixation

OpenAIRE

Fischinger, Stephanie A.; Hristozkova, Marieta; Mainassara, Zaman-Allah; Schulze, Joachim

2009-01-01

Nodule CO2 fixation via PEPC provides malate for bacteroids and oxaloacetate for N assimilation. The process is therefore of central importance for efficient nitrogen fixation. Nodule CO2 fixation is known to depend on external CO2 concentration. The hypothesis of the present paper was that nitrogen fixation in alfalfa plants is enhanced when the nodules are exposed to elevated CO2 concentrations. Therefore nodulated plants of alfalfa were grown in a hydroponic system that allowed separate ae...

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.

Outcomes following femoral lengthening: An initial comparison of the Precice intramedullary lengthening nail and the LRS external fixator monorail system.

Science.gov (United States)

Laubscher, M; Mitchell, C; Timms, A; Goodier, D; Calder, P

2016-10-01

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages. We reviewed all cases of simple femoral lengthening performed at our unit from 2009 to 2014. Cases of nonunions, concurrent deformities, congenital limb deficiencies and lengthening with an unstable hip were excluded, leaving 33 cases (in 22 patients; 11 patients had bilateral procedures) for review. Healing index, implant tolerance and complications were compared. In 20 cases (15 patients) the Precice lengthening nail was used and in 13 cases (seven patients) the LRS external fixator system. The desired length was achieved in all cases in the Precice group and in 12 of 13 cases in the LRS group. The mean healing index was 31.3 days/cm in the Precice and 47.1 days/cm in the LRS group (p < 0.001). This was associated with an earlier ability to bear full weight without aids in the Precice group. There were more complications with LRS lengthening, including pin site infections and regenerate deformity. Implant tolerance and the patients' perception of the cosmetic result were better with the Precice treatment. Femoral lengthening with the Precice femoral nail achieved excellent functional results with fewer complications and greater patient satisfaction when compared with the LRS system in our patients. Cite this article: Bone Joint J 2016;98-B:1382-8. ©2016 The British Editorial Society of Bone & Joint Surgery.

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

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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

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.

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.

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

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Dalibor Milojko Đenadić

2013-06-01

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

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

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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.

Integration of computer-assisted fracture reduction system and a hybrid 3-DOF-RPS mechanism for assisting the orthopedic surgery

Science.gov (United States)

Irwansyah; Sinh, N. P.; Lai, J. Y.; Essomba, T.; Asbar, R.; Lee, P. Y.

2018-02-01

In this paper, we present study to integrate virtual fracture bone reduction simulation tool with a novel hybrid 3-DOF-RPS external fixator to relocate back bone fragments into their anatomically original position. A 3D model of fractured bone was reconstructed and manipulated using 3D design and modeling software, PhysiGuide. The virtual reduction system was applied to reduce a bilateral femoral shaft fracture type 32-A3. Measurement data from fracture reduction and fixation stages were implemented to manipulate the manipulator pose in patient’s clinical case. The experimental result presents that by merging both of those techniques will give more possibilities to reduce virtual bone reduction time, improve facial and shortest healing treatment.

Combined fixation, intern and external, in proximal complex fractures of the tibia

International Nuclear Information System (INIS)

Quintero Laverde, Jaime; Lozano Ortiz, Victor Hugo; Rojas Duque, Guillermo

2002-01-01

Between August of 1997 and December of 2001, they were treated in the orthopedics department and traumatology of the Hospital Clinica San Rafael, 16 patients with proximal complex fractures of the tibia, using internal fixation with plate in the lateral column and an unilateral external fixer, for the medial column. It carries out a clinical and radiological pursuit with average of 27 months (minimum 4.5, maximum 40 months). In 15 patients (93,7%) it was obtained a primary consolidation and 1 case (6,2%) it presented retard in the consolidation being necessary the placement of bony implants. in 2 cases (12,5%) there was superficial infection, one in the itinerary of the nails and another in area of superficial necrosis in soft fabrics in a closed fracture. single 1 case (6,2) it presented deep infection, which, it improve with bony curettage and antibiotics. In the final radiographic evaluation, 2 cases (12,5%) they presented depression of the lateral plate; according to the functional scale of Rasmussen excellent results were obtained (27 to 30 points) in 11 cases (68,7%) and good (20 to 26 points) in 5 cases (31,2%). The radiographic results and functional global they suggest that the combination of a technique less invasive in this area criticizes, it represents a good alternative for the treatment of the proximal complex fractures of the tibia

Treatment of unstable distal radius fractures with Ilizarov circular, nonbridging external fixator.

Science.gov (United States)

Tyllianakis, Minos; Mylonas, Spyros; Saridis, Alkis; Kallivokas, Alkiviadis; Kouzelis, Antonis; Megas, Panagiotis

2010-03-01

Unstable distal radius fractures remain a challenge for the treating orthopaedic surgeon. We present a retrospective follow-up study (mean follow-up 12.5 months) of 20 patients with 21 unstable distal radius fractures that were reduced in a closed manner and stabilized with a nonbridging Ilizarov external fixator. Subsequent insertion of olive wires for interfragmentary compression was performed in cases with intra-articular fractures. According to the overall evaluation proposed by Gartland and Werley scoring system 12 wrists were classified as excellent, 6 as good, 2 as fair and 1 as poor. Grade II pin-tract infection in distal fracture fragment was detected in 3 wires from a total of 78 (3.8%) and in 4 half pins out of a total of 9 (44.4%). Pronation was the most frequently impaired movement. This was restricted in 4 patients (19%) in whom a radioulnar transfixing wire was applied. Symptoms of irritation of superficial sensory branch of the radial nerve occurred in 3 patients with an olive wire applied in a closed manner in the distal fragment. Ilizarov method yields functional results comparable to that of other methods whilst it avoids wrist immobilization, open reduction and reoperation for implant removal. The method is associated with a low rate of major complication and satisfactory functional outcome. Copyright 2009 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2010-02-01

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

Fluorescence in situ hybridization on formalin-fixed and paraffin-embedded tissue

DEFF Research Database (Denmark)

Laub Petersen, Bodil; Zeuthen, Mette Christa; Pedersen, Sanni

2004-01-01

Fluorescence in situ hybridization (FISH) is widely used to study numerical and structural genetic abnormalities in both metaphase and interphase cells. The technique is based on the hybridization of labeled probes to complementary sequences in the DNA or RNA of the cells. Interphase FISH is most...... in time lapse between removal of tissue and fixation, duration of fixation, enzymatic pretreatment, hybridization conditions, and posthybridization washing conditions are important factors in the hybridization. In this study, we have listed the results of a systematic approach to improve FISH on isolated...

Rapid maxillary distraction protocol utilizing the halo distraction system and rigid internal fixation.

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Baker, Stephen B; Reid, Russell R; Burkey, Brooke; Bartlett, Scott P

2007-09-01

To shorten head frame wear time associated with external halo distraction (HD), we have adapted a protocol for maxillary distraction with the halo system that integrates plate fixation. All patients had a history of cleft lip and/or palate and maxillary retrusion > or = 8 mm. Five patients treated with this protocol and followed for at least 1 year were included in this study. The protocol included a 3-day latency period, variable maxillary distraction, and removal of the halo device with simultaneous rigid internal fixation. Two patients had a variable period of maxillomandibular fixation (MMF), which maintained the maxillary advancement and idealized intercuspal position while permitting further callus maturation. Cephalographs were obtained preoperatively, immediately following distractor removal, and 1 year after rigid internal fixation. The mean age at time of surgery was 18.7 years. The maxillary deficiency ranged from 8 to 15 mm (mean = 10.6 mm). All five patients demonstrated excellent occlusion. Cephalometric analysis 1-year post rigid internal fixation revealed minimal (maxillary distraction followed by MMF to maintain maxillary advancement may reduce halo device wear to 1 to 2 weeks. MMF optimizes occlusion by forcing the maxillary teeth into maximal intercuspal position. Rigid fixation is not only associated with less long-term relapse compared to nonrigid forms of fixation, but also minimizes the incidence of nonunion. This treatment protocol provides the advancement possible with distraction osteogenesis and the accuracy of orthognathic surgery, thereby minimizing external head frame wear.

The use of circular external fixators in the management of lower limb trauma in Dublin: a single surgeon's 20-year experience.

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O'Neill, B J; Fox, C M; Molloy, A P; O'hEireamhoin, S; Moore, D P

2016-02-01

It has been estimated that approximately 520,000 injury presentations are made to Irish accident and emergency departments each year. Fractures account for 20 % of these injuries. Circular external fixators (frames) have been shown to be a safe and effective method of treatment for long bone fractures where internal fixation is impossible or in-advisable. We present the outcomes of all frames applied at our institution for stabilisation of acute fractures over a 20-year period. We retrospectively reviewed a prospectively compiled database of all frames applied in our institution and identified all frames which were applied for acute lower limb trauma. We identified 68 fractures in 63 patients. There were 11 femoral fractures and 57 tibial fractures. All fractures were classified using the AO Classification system, and most fractures were Type C fractures. We used an Ilizarov frame for 53 fractures and a Taylor Spatial Frame for 15 fractures. The mean time in frame was 365 days for a femoral fracture and 230 days for a tibial fracture. There were five tibial non-unions giving an overall union rate of 93 %. Factors associated with non-union included high-energy trauma and cigarette smoking. The vast majority of lower limb fractures can be treated using 'conventional' methods. Complex fractures which are not amenable to open reduction and internal fixation or cast immobilisation can be treated in a frame with excellent results. The paucity of published reports regarding the use of frames for complex trauma reflects the under-utilisation of the technique.

Ilizarov external fixation versus plate osteosynthesis in the management of extra-articular fractures of the distal tibia.

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Fadel, Mohamed; Ahmed, Mohamed Ali; Al-Dars, Ahmed Mounir; Maabed, Mustafa Ahmed; Shawki, Hashem

2015-03-01

The purpose of this study was to evaluate the outcome of Ilizarov external fixation (IE) versus dynamic compression plate (PO) in the management of extra-articular distal tibial fractures. Between 2010 and 2011, extra-articular distal tibial fractures in 40 consecutive patients met the inclusion criteria. They were classified according to AO classification fracture type A (A1, A2, and A3). In a randomized method, two equal groups were managed using either IE or PO. PO was performed using open reduction and internal fixation (ORIF) and DCP through anterolateral approach. IE was done using Ilizarov frame. For the PO group, non-weight bearing ambulation was permitted on the second postoperative day but partial weight bearing was permitted according to the progression in union criteria clinically and radiologically. For the IE group, weight bearing started as tolerated from the first postoperative day. Physiotherapy and pin-site care was performed by the patient themselves. Modified Mazur ankle score was applied to IE (excellent 10, good 10) and in PO (excellent 2, good 8, poor 6). Data were statically analysed using (Mann-Whitney test). The rate of healing in the IE group (average 130) was higher than the PO (average 196.5); plus, there were no cases of delayed union or nonunion in the IE group (p value 0.003). It was found that IE compared with PO provides provision of immediate weight bearing as tolerated following postoperative recovery, irrespective of radiological or clinical healing with no infection, deformity or non-union.

Reconstruction of the thumb with external fixer of bony lengthening

International Nuclear Information System (INIS)

Iriarte Locarno, Raymundo; Garcia Herrera, Alvaro; Bocanegra Navia, Sergio; Suarez Romero, Fabio

2005-01-01

The thumb amputation represents one of the most anti functional, unsightly and psychological disabilities of the hand. We describe the surgical technique, the bone distraction phases, additional surgeries and external fixation. We review prospectively our experience in the Military Hospital in Bogota, Colombia, from 1996 until 2003: 9 patients, men, amputation level: 1C to 4, we used a monolateral external fixator; Distraction speed: 0,75 mm/d, mean lengthening 3,9 cms, mean time with de fixation: 6 months. Bone consolidation: 100%, mild functional activity according to the disabilities of the arm, shoulder and arm score (DASH). We recommended this surgical technique, because it is easy, reproducible, and allows a functional recuperation of the thumb

Anatomy of the distal knee joint and pyarthrosis following external fixation.

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Hyman, J; Moore, T

1999-05-01

To determine the limits of the distal synovial reflection of the human knee joint. Six paired knees studied by magnetic resonance imaging (MRI), fluoroscopic arthrography, and gross dissection. The right knees of five patients with chronic idiopathic knee effusions were studied by MRI. Cadaveric knees were injected with saline prior to MRI. The joint capsules were dissected to visualize local anatomy and check for capsular tears. In each modality (MRI, fluoroscopy, and dissection), the most distal extent of knee synovial fluid was measured. The right versus left agreement for paired specimens was generally two to three millimeters. Some specimens showed asymmetric capsular reflection. Medial fluid was identified at distances greater than forty-nine millimeters from the subchondral bone in seven knees and less than fifteen millimeters in four knees (range 0 to 70 millimeters, mean thirty-three millimeters). Laterally, the range was ten to thirty-five millimeters (mean twenty-three millimeters). In six of the twelve cadaveric specimens, there was evidence of a communication between the knee joint and the proximal tibiofibularjoint. In the knees of volunteers, joint fluid tracked medially to a range of ten to fifty millimeters and laterally to a range of six to fifteen millimeters, with means of twenty-six and eleven millimeters, respectively. The knees of the volunteers had no evidence of tibiofibular joint communication with the knee. Insertion of external fixation pins within sixty to seventy millimeters of the proximal articular surface of the tibia is associated with a high probability of synovial penetration and possibly provides a conduit for the introduction of bacteria, which may be etiologic in iatrogenic pyarthrosis.

Bilateral humeral lengthening in achondroplasia with unilateral external fixators: is it safe and does it improve daily life?

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Balci, H I; Kocaoglu, M; Sen, C; Eralp, L; Batibay, S G; Bilsel, K

2015-11-01

A retrospective study was performed in 18 patients with achondroplasia, who underwent bilateral humeral lengthening between 2001 and 2013, using monorail external fixators. The mean age was ten years (six to 15) and the mean follow-up was 40 months (12 to 104). The mean disabilities of the arm, shoulder and hand (DASH) score fell from 32.3 (20 to 40) pre-operatively to 9.4 (6 to 14) post-operatively (p = 0.037). A mean lengthening of 60% (40% to 95%) was required to reach the goal of independent perineal hygiene. One patient developed early consolidation, and fractures occurred in the regenerate bone of four humeri in three patients. There were three transient radial nerve palsies. Humeral lengthening increases the independence of people with achondroplasia and is not just a cosmetic procedure. ©2015 The British Editorial Society of Bone & Joint Surgery.

Surgical correction of severe spinal deformities using a staged protocol of external and internal techniques.

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Prudnikova, Oksana G; Shchurova, Elena N

2018-02-01

There is high risk of neurologic complications in one-stage management of severe rigid spinal deformities in adolescents. Therefore, gradual spine stretching variants are applied. One of them is the use of external transpedicular fixation. Our aim was to retrospectively study the outcomes of gradual correction with an apparatus for external transpedicular fixation followed by internal fixation used for high-grade kyphoscoliosis in adolescents. Twenty five patients were reviewed (mean age, 15.1 ± 0.4 years). Correction was performed in two stages: 1) gradual controlled correction with the apparatus for external transpedicular fixation; and 2) internal posterior transpedicular fixation. Rigid deformities in eight patients required discapophysectomy. Clinical and radiographic study of the outcomes was conducted immediately after treatment and at a mean long-term period of 3.8 ± 0.4 years. Pain was evaluated using the visual analogue scale (VAS, 10 points). The Oswestry questionnaire (ODI scale) was used for functional assessment. Deformity correction with the external apparatus was 64.2 ± 4.6% in the main curve and 60.7 ± 3.7% in the compensatory one. It was 72.8 ± 4.1% and 66.2 ± 5.3% immediately after treatment and 70.8 ± 4.6% and 64.3 ± 4.2% at long term, respectively. Pain relieved by 33.2 ± 4.2% (p external transpedicular fixation provides gradual controlled correction for high-grade kyphoscoliosis in adolescents. Transition to internal fixation preserves the correction achieved, and correction is maintained at long term.

Small bowel obstruction in percutaneous fixation of traumatic pelvic fractures

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Roberto Bini

2013-01-01

Full Text Available The use of external fixation for the initial treatment of unstable, complex pelvic injuries with hemodynamic instability remains an effective treatment for multiply injured patients. Bowel entrapment within a pelvic fracture is a rarely reported, potentially fatal complication. Here, we report a polytrauma patient with pelvic fractures who developed an intestinal obstruction after an external fixation. At an explorative laparotomy, we found an ileum segment trapped in the sacral fracture. Reported cases of bowel entrapment in pelvic fractures, especially in sacral fractures, are exceedingly rare. The diagnosis is often delayed due to difficulty distinguishing entrapment from the more common adynamic ileus. In conclusion, clinicians and radiologists should be aware of this potentially lethal complication of pelvic fractures treatment. To exclude bowel entrapment, patients with persistent ileus or sepsis should undergo early investigations.

Motorized injector-assisted intrascleral intraocular lens fixation.

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Hung, Jia-Horung; Wang, Shih-Hao; Teng, Yu-Ti; Hsu, Sheng-Min

2017-03-01

For eyes with deficient capsular support, intraocular lens (IOL) implantation has long been a technical challenge. Recently, intrascleral fixation of the haptics of a three-piece posterior chamber IOL has become a popular option. In this procedure, externalization of the leading haptic during IOL injection is a stressful step. We present a modified technique to improve the ease and safety of this step. Our modified technique involves IOL injection with a motorized injector with several important modifications described here. With these modifications, a surgeon can easily maintain the correct orientation of the IOL in a well-controlled manner during IOL injection. The records of 13 patients who underwent this technique were retrospectively evaluated. Corrected-distance visual acuity improved significantly after surgery (pIOL decentration, or vitreous hemorrhage was noted during the follow-up period. In conclusion, the motorized injector-assisted intrascleral IOL fixation technique is a safe and effective alternative to the conventional procedure. This technique makes the process of leading haptic externalization easier and more controllable. Copyright © 2017. Published by Elsevier Taiwan.

Motorized injector-assisted intrascleral intraocular lens fixation

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Jia-Horung Hung

2017-03-01

Full Text Available For eyes with deficient capsular support, intraocular lens (IOL implantation has long been a technical challenge. Recently, intrascleral fixation of the haptics of a three-piece posterior chamber IOL has become a popular option. In this procedure, externalization of the leading haptic during IOL injection is a stressful step. We present a modified technique to improve the ease and safety of this step. Our modified technique involves IOL injection with a motorized injector with several important modifications described here. With these modifications, a surgeon can easily maintain the correct orientation of the IOL in a well-controlled manner during IOL injection. The records of 13 patients who underwent this technique were retrospectively evaluated. Corrected-distance visual acuity improved significantly after surgery (p<0.05. No postoperative retinal detachment, endophthalmitis, IOL decentration, or vitreous hemorrhage was noted during the follow-up period. In conclusion, the motorized injector-assisted intrascleral IOL fixation technique is a safe and effective alternative to the conventional procedure. This technique makes the process of leading haptic externalization easier and more controllable.

The management of tibial pilon fractures with the Ilizarov fixator: The role of ankle arthroscopy.

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El-Mowafi, Hani; El-Hawary, Ahmed; Kandil, Yasser

2015-12-01

Pilon fractures usually result from high energy trauma, and are commonly associated with extensive soft tissue damage which prevents the use of open reduction and internal fixation. This study was designed to evaluate the use of the Ilizarov external fixator in the treatment of pilon fractures of the ankle, and to determine whether arthroscopy of the ankle could improve the outcome. From February 2011 to May 2013 a total of 23 patients with unilateral closed pilon fractures were divided into two groups treated with and without arthroscopy during fixation with the Ilizarov external fixator. The fractures were classified according to the AO Rüdi and Allgőwer classification. Follow up ranged from 10 to 37 months with a mean of 18 months. All cases were evaluated at follow up by the AOFAS and the Bone et al. grading system. According to Bone et al. there were 3 cases excellent, 4 cases good, 2 cases fair, and 2 cases poor in Group A (without arthroscopy), whereas there were 4 cases excellent, 6 cases good, 2 cases fair in Group B (with arthroscopy). The AOFAS score for Group A was 77.8±5.8, and for Group B was 78.4±6.9. We concluded that the Ilizarov external fixator is an excellent method in treating pilon fractures as it minimizes the need for extensive surgery. We also conclude that the use of arthroscopy during pilon fracture fixation did not add statistically significant improvement to our results and it needs longer term investigation to assess its advantage - if any - to the final outcome. level 2. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cerclage wire and lag screw fixation of the lateral malleolus in supination and external rotation fractures of the ankle.

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Bajwa, Amarjit S; Gantz, D E

2005-01-01

Wound dehiscence and exposed lateral hardware can occur after open reduction internal fixation of lateral malleolus. The bulk of a lateral plate and the minimum soft tissue over the lateral malleolus may contribute to this situation. The objective of this study was to evaluate a series of patients with lateral malleolar fractures treated with operative reduction using minimal hardware. We wanted to observe whether there was any loss of reduction and whether there were any incidences of soft tissue disruption. Fifty-two patients with long spiral fracture of the lateral malleolus in a supination-external rotation injury were treated with two or three 3.5-mm lag screws inserted 1 cm apart and 1 or 2 circlage wires. Less rigid fixation was supplemented with a below-the-knee plaster cast. All patients were followed up until clinical and radiological evidence of fracture healing at 6, 10, and 14 weeks postoperatively. By 10 weeks, all patients were full weight bearing, although most patients still limped. At 14 weeks' follow-up, there were no infections or wound dehiscences. All patients were able to return to their activities of daily living. All the fractures had united without loss of original position. Two fractures of the posterior bone spikes seen during surgery united uneventfully. Long spiral fractures of the lateral malleolus of the ankle can be treated successfully with 2 or 3 lag screws and circlage wires without compromising the outcome of the fracture healing.

An improvement of the fixation method for preimplantation genetic diagnosis by fluorescent in situ hybridization%植入前遗传学诊断中单卵裂球固定方法的相关研究

Institute of Scientific and Technical Information of China (English)

张敏敏; 章志国; 周平; 曹云霞

2012-01-01

目的 以人类受精胚胎单卵裂球为对象,对传统低渗固定法进行改良,探讨一种更简便效率更高的固定方法.方法 收集30枚人类多精受精胚胎激光打孔后去除透明带,将获得的完整卵裂球按传统低渗固定法和直接固定法进行固定后行X,Y染色体双色荧光原位杂交,比较固定率和杂交率.结果 固定卵裂球共171枚.低渗固定法(A组)固定80枚,成功68枚,成功率为85.0%.直接固定法(B)组固定91枚,成功82枚,成功率为90.1%.两组差异有显著性.A组杂交率为77.5%(每卵裂球数),91.2%(每核数),B组杂交率为83.5%(每卵裂球数)92.7%(每核数).两组差异无显著性.结论 直接固定法简化了固定步骤,降低了细胞丢失率,为较理想的单个卵裂球间期核固定技术.%Objective To improve current preimplantation genetic diagnosis fixation techniques in order to find a more efficient fixation method by using polyspermy embryos. Methods At first,to remove the zona pellucida by laser. The Integrity Blastomeres were distributed into two groups: conventional hypotonic- fixationgroup and direct-fixation group. Fluorescence in situ hybridization was accomplished after fixation using chromosome X and Y probes,and then the fixation rate and the fluorescent signals were analyzed. Result 1. A total of 30 Blastomeres were analyzed and 171 Blastomeres fixated. Of the 80 Blastomeres in conventional group (A group) ,68 got fine fixation, the successful rate was 85.0%. Among 91 Blastomeres in direct-fixation group (B group) ,82 got fine fixation, the successful rate was 90. 1% . 2. In conventional group, the hybridization rate was 77. 5% (/ Blastomere) or 91. 2% (/Nuclear) . The rate were 83. 5% and 92.7% respectively with hypotonic-fixation group and the direct-fixation group. There was no Significant difference. Conclusion This improved fixation technique essentially eliminates the possibility of losing a cell during fixation and simplifies the process of

Avaliação pós-operatória da fixação esquelética externa em 29 cães: estudo retrospectivo Post surgical evaluation of external skeletal fixation in 29 dogs: a retrospective study

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C.M.F. Rezende

2006-04-01

Full Text Available In this retrospective study 29 dogs of both sexes of several breeds, were evaluated. Complications of external skeletal fixation were common. The most frequent post-surgical complications were chronic pin track drainage or pin loosing (11; 37.9%, followed by dry crust at the skin-to-pin interface (5; 17.1%. In five cases (17.1% occurred the healing of the fracture without complications. In three dogs (10.4% occurred nonunion and it was used another fixation method. It was observed individual cases of poor limb use (3.5% or breakage of the pin (3.5% or of the acrylic column (3.5%. Pin track drainage or loosing was related to the owners care. The most did not come back to the hospital as was demanded or did not follow the instructions to inspect the apparatus daily. This behaviour contributed to increase the rate of post-surgical complications. The external fixation has the advantage to be less invasive and can be used to treat closed and open fractures, limb deformities, nonunion and infected fractures.

Implant Material, Type of Fixation at the Shaft, and Position of Plate Modify Biomechanics of Distal Femur Plate Osteosynthesis.

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Kandemir, Utku; Augat, Peter; Konowalczyk, Stefanie; Wipf, Felix; von Oldenburg, Geert; Schmidt, Ulf

2017-08-01

To investigate whether (1) the type of fixation at the shaft (hybrid vs. locking), (2) the position of the plate (offset vs. contact) and (3) the implant material has a significant effect on (a) construct stiffness and (b) fatigue life in a distal femur extraarticular comminuted fracture model using the same design of distal femur periarticular locking plate. An extraarticular severely comminuted distal femoral fracture pattern (OTA/AO 33-A3) was simulated using artificial bone substitutes. Ten-hole distal lateral femur locking plates were used for fixation per the recommended surgical technique. At the distal metaphyseal fragment, all possible locking screws were placed. For the proximal diaphyseal fragment, different types of screws were used to create 4 different fixation constructs: (1) stainless steel hybrid (SSH), (2) stainless steel locked (SSL), (3) titanium locked (TiL), and (4) stainless steel locked with 5-mm offset at the diaphysis (SSLO). Six specimens of each construct configuration were tested. First, each specimen was nondestructively loaded axially to determine the stiffness. Then, each specimen was cyclically loaded with increasing load levels until failure. Construct Stiffness: The fixation construct with a stainless steel plate and hybrid fixation (SSH) had the highest stiffness followed by the construct with a stainless steel plate and locking screws (SSL) and were not statistically different from each other. Offset placement (SSLO) and using a titanium implant (TiL) significantly reduced construct stiffness. Fatigue Failure: The stainless steel with hybrid fixation group (SSH) withstood the most number of cycles to failure and higher loads, followed by the stainless steel plate and locking screw group (SSL), stainless steel plate with locking screws and offset group (SSLO), and the titanium plate and locking screws group (TiL) consecutively. Offset placement (SSLO) as well as using a titanium implant (TiL) reduced cycles to failure. Using the

Fixation distance and fixation duration to vertical road signs.

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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.

Comparison of cemented and uncemented fixation in total knee arthroplasty.

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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.

Reduction and temporary stabilization of Tile C pelvic ring injuries using a posteriorly based external fixation system.

Science.gov (United States)

Martin, Murphy P; Rojas, David; Mauffrey, Cyril

2017-12-05

Tile C pelvic ring injuries are challenging to manage even in the most experienced hands. The majority of such injuries can be managed using percutaneous reduction techniques, and the posterior ring can be stabilized using percutaneous transiliac-transsacral screw fixation. However, a subgroup of patients present with inadequate bony corridors, significant sacral zone 2 comminution or significant lateral/vertical displacement of the hemipelvis through a complete sacral fracture. Percutaneous strategies in such circumstances can be dangerous. Those patients may benefit from prone positioning and open reduction of the sacral fracture with fixation through tension band plating or lumbo-pelvic fixation. Soft tissue handling is critical, and direct reduction techniques around the sacrum can be difficult due to the complex anatomy and the fragile nature of the sacrum making clamp placement and tightening a challenge. In this paper, we propose a mini-invasive technique of indirect reduction and temporary stabilization, which is soft tissue friendly and permits maintenance of reduction during definitive fixation surgical.

A new fixation strategy for addressable nano-network building blocks

KAUST Repository

Lundberg, Erik P.; El-Sagheer, Afaf H.; Kocalka, Petr; Wilhelmsson, L. Marcus; Brown, Tom; Nordé n, Bengt

2010-01-01

Rapid controlled self-assembly makes DNA ideal for building nanostructures. A problem using hybridized intermediates in hierarchic assembly is their thermodynamic lability. We demonstrate a click-fixation technology by which robust hexagonal DNA modules can be made. This principle is applicable to a wide variety of DNA nanoconstructs. © 2010 The Royal Society of Chemistry.

Treatment of reducible unstable fractures of the distal radius: randomized clinical study comparing the locked volar plate and external fixator methods: study protocol.

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Raduan Neto, Jorge; de Moraes, Vinicius Ynoe; Gomes Dos Santos, João B; Faloppa, Flávio; Belloti, João Carlos

2014-03-05

Various treatments are available for reducible unstable fractures of the distal radius, such as closed reduction combined with fixation by external fixator (EF), and rigid internal fixation using a locked volar plate (VP). Although there are studies comparing these methods, there is no conclusive evidence indicating which treatment is best. The hypothesis of this study is that surgical treatment with a VP is more effective than EF from the standpoint of functional outcome (patient-reported). The study is randomized clinical trial with parallel groups and a blinded evaluator and involves the surgical interventions EF and VP. Patients will be randomly assigned (assignment ratio 1:1) using sealed opaque envelopes. This trial will include consecutive adult patients with an acute (up to 15 days) displaced, unstable fracture of the distal end of the radius of type A2, A3, C1, C2 or C3 by the Arbeitsgemeinschaft für Osteosynthesefragen-Association for the Study of Internal Fixation classification and type II or type III by the IDEAL32 classification, without previous surgical treatments of the wrist. The surgical intervention assigned will be performed by three surgical specialists familiar with the techniques described. Evaluations will be performed at 2, and 8 weeks, 3, 6 and 12 months, with the primary outcomes being measured by the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and measurement of pain (Visual Analog Pain Scale and digital algometer). Secondary outcomes will include radiographic parameters, objective functional evaluation (goniometry and dynamometry), and the rate of complications and method failure according to the intention-to-treat principle. Final postoperative evaluations (6 and 12 months) will be performed by independent blinded evaluators. For the Student's t-test, a difference of 10 points in the DASH score, with a 95% confidence interval, a statistical power of 80%, and 20% sampling error results in 36 patients per group

[Effect of axial stress stimulation on tibial and fibular open fractures healing after Taylor space stent fixation].

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Ge, Qihang; Wan, Chunyou; Liu, Yabei; Ji, Xu; Ma, Jihai; Cao, Haikun; Yong, Wei; Liu, Zhao; Zhang, Ningning

2017-08-01

To investigate the effect of axial stress stimulation on tibial and fibular open fractures healing after Taylor space stent fixation. The data of 45 cases with tibial and fibular open fractures treated by Taylor space stent fixation who meet the selection criteria between January 2015 and June 2016 were retrospectively analysed. The patients were divided into trial group (23 cases) and control group (22 cases) according to whether the axial stress stimulation was performed after operation. There was no significant difference in gender, age, affected side, cause of injury, type of fracture, and interval time from injury to operation between 2 groups ( P >0.05). The axial stress stimulation was performed in trial group after operation. The axial load sharing ratio was tested, and when the value was less than 10%, the external fixator was removed. The fracture healing time, full weight-bearing time, and external fixator removal time were recorded and compared. After 6 months of external fixator removal, the function of the limb was assessed by Johner-Wruhs criteria for evaluation of final effectiveness of treatment of tibial shaft fractures. There were 2 and 3 cases of needle foreign body reaction in trial group and control group, respectively, and healed after symptomatic anti allergic treatment. All the patients were followed up 8-12 months with an average of 10 months. All the fractures reached clinical healing, no complication such as delayed union, nonunion, or osteomyelitis occurred. The fracture healing time, full weight-bearing time, and external fixator removal time in trial group were significantly shorter than those in control group ( P good in 6 cases, fair in 3 cases, and poor in 1 case in trial group, with an excellent and good rate of 82.6%; and was excellent in 5 cases, good in 10 cases, fair in 4 cases, and poor in 3 cases in control group, with an excellent and good rate of 68.2%, showing significant difference between 2 groups ( Z =-2.146, P =0

SURGICAL TREATMENT OF PATIENTS WITH HALLUX VALGUS BY MINI-APPARATUS OF EXTERNAL FIXATION

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K.K. Levchenko

2008-06-01

Full Text Available The authors of article suggest methods of surgical correction of pathology by means of fixation of the first metatarsal bone with specialconstruction ofmini-apparatus for externalfixation. This approach provides decrease of recovery period, reduces complications riskas well as deformation relapse.

Proximal femoral resection and articulated hip distraction with an external fixator for the treatment of painful spastic hip dislocations in pediatric patients with spastic quadriplegia.

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Lampropulos, Mario; Puigdevall, Miguel H; Zapozko, Daniel; Malvárez, Héctor R

2008-01-01

We describe the results obtained with an alternative method of treatment for spastic painful hip dislocations in nonambulatory patients, which consists of a proximal femoral resection with capsular interposition arthroplasty, and the addition of a hinged external fixator for postoperative articulated hip distraction to allow for an immediate upright position and the ability to sit in a wheelchair. We performed this technique in three patients (four hips) with a mean age at the time of surgery of 15 years. Postoperatively, clinical improvement was observed in all four hips, with respect to pain relief, sitting tolerance, perineal care and functional range of motion.

The cyanobacterial nitrogen fixation paradox in natural waters [version 1; referees: 2 approved

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Hans Paerl

2017-03-01

Full Text Available Nitrogen fixation, the enzymatic conversion of atmospheric N (N2 to ammonia (NH3, is a microbially mediated process by which “new” N is supplied to N-deficient water bodies. Certain bloom-forming cyanobacterial species are capable of conducting N2 fixation; hence, they are able to circumvent N limitation in these waters. However, this anaerobic process is highly sensitive to oxygen, and since cyanobacteria produce oxygen in photosynthesis, they are faced with a paradoxical situation, where one critically important (for supporting growth biochemical process is inhibited by another. N2-fixing cyanobacterial taxa have developed an array of biochemical, morphological, and ecological adaptations to minimize the “oxygen problem”; however, none of these allows N2 fixation to function at a high enough efficiency so that it can supply N needs at the ecosystem scale, where N losses via denitrification, burial, and advection often exceed the inputs of “new” N by N2 fixation. As a result, most marine and freshwater ecosystems exhibit chronic N limitation of primary production. Under conditions of perpetual N limitation, external inputs of N from human sources (agricultural, urban, and industrial play a central role in determining ecosystem fertility and, in the case of N overenrichment, excessive primary production or eutrophication. This points to the importance of controlling external N inputs (in addition to traditional phosphorus controls as a means of ensuring acceptable water quality and safe water supplies. Nitrogen fixation, the enzymatic conversion of atmospheric N2 to ammonia (NH3 is a  microbially-mediated process by which “new” nitrogen is supplied to N-deficient water bodies.  Certain bloom-forming cyanobacterial species are capable of conducting N2 fixation; hence they are able to circumvent nitrogen limitation in these waters. However, this anaerobic process is highly sensitive to oxygen, and since cyanobacteria produce

Longitudinal bracketed epiphysis of proximal phalanx of the great toe with congenital hallux varus managed simultaneously with monorail external fixator: a case report.

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Verma, Vineet; Batra, Amit; Singla, Rohit; Gogna, Paritosh; Magu, Narender; Gupta, Rakesh

2014-02-01

Longitudinal bracketed epiphysis (delta phalanx) is a rare congenital anomaly that affects phalanges in the hand more commonly than toes. We present a rare case of congenital hallux varus with longitudinal bracketed epiphysis of proximal phalanx with bifid distal phalanx of the great toe, which was managed with monorail type of external fixator. To the best of our knowledge, this is the first report of its successful implementation in simultaneous treatment of longitudinal bracketed epiphysis of the proximal phalanx of the great toe and hallux varus. Apart from adding to the literature a case of rare subtype of delta phalanx with hallux varus, the present study highlights the role of a reliable alternative in its management.

Hybrid Endovascular Aortic Aneurysm Repair: Preservation of Pelvic Perfusion with External to Internal Iliac Artery Bypass.

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Mansukhani, Neel A; Havelka, George E; Helenowski, Irene B; Rodriguez, Heron E; Hoel, Andrew W; Eskandari, Mark K

2017-07-01

Diminished pelvic arterial flow as a result of intentional coverage/embolization of internal iliac arteries (IIA) during isolated endovascular common iliac artery aneurysm (CIAA) repair or endovascular repair of abdominal aortic aneurysms (EVAR) may result in symptomatic pelvic ischemia. Although generally well tolerated, in severe cases, pelvic ischemia may manifest as recalcitrant buttock claudication, vasculogenic impotence, or perineal, vesicle, rectal, and/or spinal cord ischemia. Branched graft technology has recently become available; however, many patients are not candidates for endovascular repair with these devices. Therefore, techniques to preserve pelvic arterial flow are needed. We reviewed our outcomes of isolated endovascular CIAA repair or EVAR in conjunction with unilateral external-internal iliac artery bypass. Single-center, retrospective review of 10 consecutive patients who underwent hybrid endovascular abdominal aortic aneurysm (AAA) or CIAA repair with concomitant external-internal iliac artery bypass between 2006 and 2015. Demographics, index procedural details, postoperative symptoms, hospital length of stay (LOS), follow-up imaging, and bypass patency were recorded. The cohort of 10 patients was all men with a mean age of 71 years (range: 56-84). Hybrid repair consisted of contralateral IIA coil embolization followed by EVAR with external iliac artery-internal iliac artery (EIA-IIA) bypass. All EIA-IIA bypasses were performed via a standard lower quadrant retroperitoneal approach with a prosthetic bypass graft. Technical success was 100%, and there were no perioperative deaths. One patient developed transient paraplegia, 1 patient had buttock claudication on the side of his hypogastric embolization contralateral to his iliac bypass, and 1 developed postoperative impotence. 20% of patients sustained long-term complications (buttock claudication and postoperative impotence). Mean LOS was 2.8 days (range: 1-9 days). Postoperative imaging

[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].

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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

Effective Application of the Methanol-Based PreservCyt (TM) Fixative and the Cellient (TM) Automated Cell Block Processor to Diagnostic Cytopathology, Immunocytochemistry, and Molecular Biology

NARCIS (Netherlands)

van Hemel, Bettien M.; Suurmeijer, Albert J. H.

We studied the feasibility of immunocytochemistry (ICC), in situ hybridization (ISH), and polymerase chain reaction (PCR) after Cellient automated cell block processing, and tested whether methanol-based PreservCyt fixation could replace formalin fixation, in an attempt to eliminate toxic

Treament of Tibial Plateau Schatzker Type VI Fractures with the Ilizarov Technique Using Ring External Fixators Across the Knee: A Retrospective Review

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IR Ranatunga

2010-07-01

Full Text Available This is a retrospective review of 18 patients with tibial plateau fractures Schatzker type VI. These cases were performed in our medical centre from January 2003 to December 2004. The Ilizarov technique (Russian technique using the ring external fixator was the technique performed. Articular reconstruction and joint alignment were achieved with traction and olive wires with washers. One case required percutaneous elevation of the articular surface and bone grafting through a cortical window. Average clinical union was achieved within 4 months of trauma. Mean final knee flexion was 85°, which is compatible with walking. All patients successfully returned to their previous occupations. In conclusion, the Ilizarov technique has been shown to be a good option and a viable tool in the management of these complex and unstable injuries.

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

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

1992-08-01

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

Self-organizing hybrid Cartesian grid generation and application to external and internal flow problems

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Deister, F.; Hirschel, E.H. [Univ. Stuttgart, IAG, Stuttgart (Germany); Waymel, F.; Monnoyer, F. [Univ. de Valenciennes, LME, Valenciennes (France)

2003-07-01

An automatic adaptive hybrid Cartesian grid generation and simulation system is presented together with applications. The primary computational grid is an octree Cartesian grid. A quasi-prismatic grid may be added for resolving the boundary layer region of viscous flow around the solid body. For external flow simulations the flow solver TAU from the ''deutsche zentrum fuer luft- und raumfahrt (DLR)'' is integrated in the simulation system. Coarse grids are generated automatically, which are required by the multilevel method. As an application to an internal problem the thermal and dynamic modeling of a subway station is presented. (orig.)

New fixation method for maxillary distraction osteogenesis using locking attachments.

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Suzuki, Eduardo Yugo; Buranastidporn, Boonsiva; Ishii, Masatoshi

2006-10-01

The external traction hooks of the intraoral splint used in the rigid external distraction (RED) system for maxillary distraction osteogenesis interfere with the surgical procedures. The purpose of this study is to introduce an innovative splint fixation method for maxillary distraction osteogenesis with Locking Attachments and evaluate their advantages, such as reduction of operating time compared with the traditional intraoral splint method. Retrospective comparison of operative times of maxillary Le Fort I osteotomy procedures was carried out with the traditional protocol using the intraoral splint cemented to the maxillary dentition (n = 14), and a removable intraoral splint that is inserted postsurgically (n = 14). Operative procedure times were compared and analyzed statistically using the data extracted from the surgical records. There were no complications inserting the removable splint postsurgically, including pain, discomfort, or time-consuming procedure. Stable and secure splint fixation was obtained before the distraction procedure and the desired treatment goals were obtained in all patients. The total operative procedure times were significantly reduced in the Locking Attachments group by 24% to 41% (approximately 65 minutes) compared with earlier operations involving the conventional splints (P Maxillary distraction osteogenesis with the Locking Attachments is a highly effective fixation approach to manage severe hypoplastic maxilla, eliminating lip constraints resulting from scarring and allowing for easier, more deliberate and careful dissection. The use of the Locking Attachments is reliable in craniofacial surgery and has proved to be advantageous in the reduction of the operating time and surgical risks.

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

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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.

[Manipulative reduction and external fixation with cardboard splint for the treatment of calcaneal fractures: a 60-case report].

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Hao, Bo-Chuan; Xie, Ke-Bo

2014-07-01

To investigate the therapeutic effects of manipulative reduction for calcaneal fractures. From January 2009 to June 2012, 53 cases (60 affected feet) of Sanders type I-IV calcaneal fractures were treated by manipulative reduction and external fixation with cardboard splint,including 45 males and 8 females with an average age of (33.5 +/- 1.54) years old ranging from 18 to 65. The course of disease ranged 0.5 h to 7 d. Before treatment the feet were swelling, ache and activity limitation in evidence, some feet were wide flat deformity, the cortical bone was broken in the imaging examination. All selected cases were evaluated using Creighton-Nebraska health foundation assessment scale for fractures of calcaneus. All cases were followed up at 12 months after treatment, 13 feet got excellent curative effect, 34 good, 11 moderate and 2 poor. Manipulative reduction for Sanders type I-IV calcaneal fractures could get excellent curative effect. Manipulative reduction for calcaneal fractures could avoid surgical trauma while assure high curative effects. Manipulative reduction is not only economical and easy therapy, but also can restore maximum function of the calcaneus with few complications and facilitate early rehabilitation of ankle and joint function.

Finite element analysis of a novel pin-sleeve system for external fixation of distal limb fractures in horses.

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Brianza, Stefano; Brighenti, Vittoria; Lansdowne, Jennifer L; Schwieger, Karsten; Bouré, Ludovic

2011-11-01

The transfixation pin cast (TPC) is an external skeletal fixation technique used to treat horses with distal limb fractures, but its use is often associated with pin-loosening and an increased risk of treatment failure. To address implant loosening, the pin sleeve cast system (PSC) was recently designed and consists of a pin-sleeve unit inserted into the bone. Each pin runs through a sleeve placed in the bone, making contact at two fixed points only within the sleeve. Each pin is attached to a ring embedded in a resin cast. In this report, the mechanical performance of a traditional TPC pin arrangement was compared with that of the PSC using validated finite element models of bone substitutes previously tested in vitro. The PSC resulted in a marked reduction in peak strain magnitude around the pins and a more even distribution of strain across the bone cortex. The two systems resulted in comparable proximal fragment displacement and had a similar stress concentration around bone defects during implant removal. The findings suggest that the PSC load transfer mechanism is effective even in geometrically complex structures like equine bones. Copyright © 2010 Elsevier Ltd. All rights reserved.

ADHD and the externalizing spectrum: direct comparison of categorical, continuous, and hybrid models of liability in a nationally representative sample.

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Carragher, Natacha; Krueger, Robert F; Eaton, Nicholas R; Markon, Kristian E; Keyes, Katherine M; Blanco, Carlos; Saha, Tulshi D; Hasin, Deborah S

2014-08-01

Alcohol use disorders, substance use disorders, and antisocial personality disorder share a common externalizing liability, which may also include attention-deficit hyperactivity disorder (ADHD). However, few studies have compared formal quantitative models of externalizing liability, with the aim of delineating the categorical and/or continuous nature of this liability in the community. This study compares categorical, continuous, and hybrid models of externalizing liability. Data were derived from the 2004-2005 National Epidemiologic Survey on Alcohol and Related Conditions (N = 34,653). Seven disorders were modeled: childhood ADHD and lifetime diagnoses of antisocial personality disorder (ASPD), nicotine dependence, alcohol dependence, marijuana dependence, cocaine dependence, and other substance dependence. The continuous latent trait model provided the best fit to the data. Measurement invariance analyses supported the fit of the model across genders, with females displaying a significantly lower probability of experiencing externalizing disorders. Cocaine dependence, marijuana dependence, other substance dependence, alcohol dependence, ASPD, nicotine dependence, and ADHD provided the greatest information, respectively, about the underlying externalizing continuum. Liability to externalizing disorders is continuous and dimensional in severity. The findings have important implications for the organizational structure of externalizing psychopathology in psychiatric nomenclatures.

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

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John Mukhopadhaya

2017-01-01

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

Single-suture scleral fixation of subluxated foldable intraocular lenses.

Science.gov (United States)

Yarangumeli, Alper; Alp, Mehmet Numan; Kural, Gulcan

2012-01-01

To evaluate the results of single-suture scleral fixation of subluxated foldable intraocular lenses (IOL) in eyes with sufficient residual capsular support. The results of IOL repositioning by single-suture scleral fixation in 6 eyes of 6 patients with IOL subluxation were included. All subluxated IOLs were single-piece hydrophilic acrylic. Subluxation resulted from posterior capsule tears in 3 eyes, zonular dialyses in 2 eyes, and zonular dialysis with a capsulorhexis tear in 1 eye. A similar technique was used in all eyes in which one haptic was externalized through a superior clear corneal incision and tied with a Pair-PAK 10-0 polypropylene suture, and was finally retracted and fixated behind the iris close to the ciliary sulcus at the 12:00 meridian. All patients were followed up for at least 6 months. Best-corrected visual acuities ranged between finger counting and 20/70 (mean logMAR 1.02±0.64) preoperatively, and between 20/100 and 20/20 (mean logMAR 0.22±0.26) at the final postoperative visit. All IOLs remained centered and no significant postoperative complications were encountered except for an IOL tilt which resulted in a considerable oblique astigmatism in one eye. Subluxated foldable IOLs may safely be repositioned and secured with a single scleral fixation suture in selected cases with adequate amount of capsular remnants.

High-Power Hybrid Mode-Locked External Cavity Semiconductor Laser Using Tapered Amplifier with Large Tunability

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Andreas Schmitt-Sody

2008-01-01

Full Text Available We report on hybrid mode-locked laser operation of a tapered semiconductor amplifier in an external ring cavity, generating pulses as short as 0.5 ps at 88.1 MHz with an average power of 60 mW. The mode locking is achieved through a combination of a multiple quantum well saturable absorber (>10% modulation depth and an RF current modulation. This designed laser has 20 nm tuning bandwidth in continuous wave and 10 nm tuning bandwidth in mode locking around 786 nm center wavelength at constant temperature.

Intrascleral IOL Fixation.

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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.

Optimized breeding strategies for multiple trait integration: II. Process efficiency in event pyramiding and trait fixation.

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Peng, Ting; Sun, Xiaochun; Mumm, Rita H

2014-01-01

Multiple trait integration (MTI) is a multi-step process of converting an elite variety/hybrid for value-added traits (e.g. transgenic events) through backcross breeding. From a breeding standpoint, MTI involves four steps: single event introgression, event pyramiding, trait fixation, and version testing. This study explores the feasibility of marker-aided backcross conversion of a target maize hybrid for 15 transgenic events in the light of the overall goal of MTI of recovering equivalent performance in the finished hybrid conversion along with reliable expression of the value-added traits. Using the results to optimize single event introgression (Peng et al. Optimized breeding strategies for multiple trait integration: I. Minimizing linkage drag in single event introgression. Mol Breed, 2013) which produced single event conversions of recurrent parents (RPs) with ≤8 cM of residual non-recurrent parent (NRP) germplasm with ~1 cM of NRP germplasm in the 20 cM regions flanking the event, this study focused on optimizing process efficiency in the second and third steps in MTI: event pyramiding and trait fixation. Using computer simulation and probability theory, we aimed to (1) fit an optimal breeding strategy for pyramiding of eight events into the female RP and seven in the male RP, and (2) identify optimal breeding strategies for trait fixation to create a 'finished' conversion of each RP homozygous for all events. In addition, next-generation seed needs were taken into account for a practical approach to process efficiency. Building on work by Ishii and Yonezawa (Optimization of the marker-based procedures for pyramiding genes from multiple donor lines: I. Schedule of crossing between the donor lines. Crop Sci 47:537-546, 2007a), a symmetric crossing schedule for event pyramiding was devised for stacking eight (seven) events in a given RP. Options for trait fixation breeding strategies considered selfing and doubled haploid approaches to achieve homozygosity

Ilizarov fixator in management of nonunited and infected tibial shaft fractures

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Abhinay Singh

2015-01-01

Full Text Available Background: Management of nonunion with bony defect and infection in long bones is a challenging problem for orthopedic surgeons. Objectives: Evaluation of Ilizarov circular fixation method of treatment for the management of nonunited and infected fractures of tibia. Materials and Methods: This prospective study was conducted in a tertiary care hospital of eastern region of India on 30 subjects in a time span of 3 years after taking clearance of the Institutional Ethical Committee and informed consent of the patients. Results: All the patients had infected nonunion before undergoing Ilizarov procedure. Following initial injury, 22 patients were treated with external fixation and 8 cases were treated with internal fixation. At the time of presentation, 18 patients had infected gap nonunion, 5 patients had infected hypertrophic and 2 patients had atrophic nonunion. The Ilizarov fixator was kept for an average period of 303.7 days. Based on Association for the Study and Application of Methods of Ilizarov scoring system, bony and functional results were assessed. The bony result was excellent in 16 patients, good in eight, fair in four and poor in two. The functional result was excellent in 10 patients, good in 16, fair in two, poor in two. Conclusion: Ilizarov ring fixator still remains an excellent treatment modality for tibial nonunion with a defect, regarding bone union, deformity correction, infection eradication, limb-length achievement, and limb function.

The use of external fixators in the definitive stabilisation of the pelvis in polytrauma patients: Safety, efficacy and clinical outcomes.

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Tosounidis, Theodoros H; Sheikh, Hassaan Qaiser; Kanakaris, Nikolaos K; Giannoudis, Peter V

2017-06-01

To analyse the complications and outcomes (functional/radiographic) of Pelvic External Fixators applied as part of the definitive fixation in polytrauma patients. A single center retrospective chart review. A level-1 trauma center. We reviewed all the polytrauma patients (ISS>16) between 2007 and 2012 that had a PEF applied more than 30days. Complications including infection, aseptic loosening, neurological injury, loss of reduction, non-union and mal-union were recorded. Pelvic asymmetry and Deformity Index (DI) were measured at the immediate postoperative radiographs and final follow-up. The functional outcome at final follow up was estimated using a scale previously reported by Chiou et al. 59 patients with mean age of 38.4 (16 - 81) years and mean ISS score 28 (16- 66) were included. The PEFs were applied for mean duration of 56 (30-104) days. The average follow-up was 403days. 22 injuries were type B and 37 type C (AO/OTA). The most common symptomatic complications were pin site infection in 11 (18.6%) and loosening in 5 (8.5%) cases. 44 (74.5%) patients had satisfactory functional outcome. The immediate post-operative and final asymmetry and DI were compared between the two pelvic injury groups (type B and C fractures). The difference in displacement progression was more for type C injuries (p=0.034) but no correlation to the functional outcome was evident. PEF can be used as definitive alternative stabilization method in specific situations at polytrauma setting. Radiological displacement occurred in both type B and C injuries but the clinical outcome was not correlated to this displacement. Complications related to PEF do not affect the final clinical outcome. Therapeutic Level III. Copyright © 2017 Elsevier Ltd. All rights reserved.

Correction of tibial malunion in a patient with ipsilateral total knee and ankle prostheses using external ring fixation and the ilizarov method

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Alexander M Smith

2017-01-01

Full Text Available Total ankle replacement (TAR aims at reestablishing a functional and painless ankle joint while maintaining motion and preventing adjacent joint arthritis. TAR can be complicated by comorbidities such as ipsilateral knee arthritis and deformity with subsequent arthroplasty and/or other lower extremity malalignment issues. We present a case of a 67-year-old female with severe right ankle pain and a history of ipsilateral subtalar and calcaneocuboid fusion, bilateral total knee arthroplasty, and a malunion of a conservatively treated ipsilateral segmental tibial fracture. Following TAR, there was recurrent lateral hindfoot pain due to subtle malalignment from the tibial malunion which resulted in persistent hindfoot valgus. This caused symptomatic subfibular impingement in addition to limb length discrepancy. To address that, a circular external fixator was applied to realign the ankle and lengthen the tibia, eliminating pain and avoiding complications with either implant.

Anterior-inferior tibiofibular ligament anatomical repair and augmentation versus trans-syndesmosis screw fixation for the syndesmotic instability in external-rotation type ankle fracture with posterior malleolus involvement: A prospective and comparative study.

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Zhan, Yu; Yan, Xiaoyu; Xia, Ronggang; Cheng, Tao; Luo, Congfeng

2016-07-01

Syndesmosis injury is common in external-rotation type ankle fractures (ERAF). Trans-syndesmosis screw fixation, the gold-standard treatment, is currently controversial for its complications and biomechanical disadvantages. The purpose of this study was to introduce a new method of anatomically repairing the anterior-inferior tibiofibular ligament (AITFL) and augmentation with anchor rope system to treat the syndesmotic instability in ERAF with posterior malleolus involvement and to compare its clinical outcomes with that of trans-syndesmosis screw fixation. 53 ERAFs with posterior malleolus involvement received surgery, and the syndesmosis was still unstable after fracture fixation. They were randomised into screw fixation group and AITFL anatomical repair with augmentation group. Reduction quality, syndesmosis diastasis recurrence, pain (VAS score), time back to work, Olerud-Molander ankle score and range of motion (ROM) of ankle were investigated. Olerud-Molander score in AITFL repair group and screw group was 90.4 and 85.8 at 12-month follow-up (P>0.05). Plantar flexion was 31.2° and 34.3° in repair and screw groups (P=0.04). Mal-reduction happened in 5 cases (19.2%) in screw group while 2 cases (7.4%) in repair group. Postoperative syndesmosis re-diastasis occurred in 3 cases in screw group while zero in repair group (P>0.05). Pain score was similar between the two groups (P>0.05). Overall complication rate and back to work time were 26.9% and 3.7% (P=0.04), 7.15 months and 5.26 months (P=0.02) in screw group and repair group, respectively. For syndesmotic instability in ERAF with posterior malleolus involvement, the method of AITFL anatomical repair and augmentation with anchor rope system had an equivalent functional outcome and reduction, earlier rehabilitation and less complication compared with screw fixation. It can be selected as an alternative. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fixation effect of SurePath preservative fluids using epidermal growth factor receptor mutation-specific antibodies for immunocytochemistry.

Science.gov (United States)

Kawahara, Akihiko; Taira, Tomoki; Abe, Hideyuki; Watari, Kosuke; Murakami, Yuichi; Fukumitsu, Chihiro; Takase, Yorihiko; Yamaguchi, Tomohiko; Azuma, Koichi; Akiba, Jun; Ono, Mayumi; Kage, Masayoshi

2014-02-01

Cytological diagnosis of respiratory disease has become important, not only for histological typing using immunocytochemistry (ICC) but also for molecular DNA analysis of cytological material. The aim of this study was to investigate the fixation effect of SurePath preservative fluids. Human lung cancer PC9 and 11-18 cell lines, and lung adenocarcinoma cells in pleural effusion, were fixed in CytoRich Blue, CytoRich Red, 15% neutral-buffered formalin, and 95% ethanol, respectively. PC9 and 11-18 cell lines were examined by ICC with epidermal growth factor receptor (EGFR) mutation-specific antibodies, the EGFR mutation DNA assay, and fluorescence in situ hybridization. The effect of antigenic storage time was investigated in lung adenocarcinoma cells in pleural effusion by ICC using the lung cancer detection markers. PC9 and 11-18 cell lines in formalin-based fixatives showed strong staining of EGFR mutation-specific antibodies and lung cancer detection markers by ICC as compared with ethanol-based fixatives. DNA preservation with CytoRich Blue and CytoRich Red was superior to that achieved with 95% ethanol and 15% neutral-buffered formalin fixatives, whereas EGFR mutations by DNA assay and EGFR gene amplification by fluorescence in situ hybridization were successfully identified in all fixative samples. Although cytoplasmic antigens maintained high expression levels, expression levels in nuclear antigens fell as storage time increased. These results indicate that CytoRich Red is not only suitable for ICC with EGFR mutation-specific antibodies, but also for DNA analysis of cytological material, and is useful in molecular testing of lung cancer, for which various types of analyses will be needed in future. © 2013 American Cancer Society.

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

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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.

Fixação externa em fratura completa de metacarpo em potros External fixation in complete metacarpal fracture in foals

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Marcelo Jorge Cavalcanti de Sá

1997-08-01

Full Text Available A regeneração de fraturas nos membros de eqüinos é complexa pelas características da espécie. Baseado em estudo biomecânico prévio, dez potros com fratura iatrogênica experimental do metacarpo tiveram redução pelo método de transfixação óssea. Cada animal foi avaliado mediante exames clínico, laboratorial e radiográfico até a recuperação. As complicações não foram significativas, exceto em um potro que requereu eutanásia. O método mostrou-se adequado e oferece estabilidade suficiente para cicatrização.The fracture healing in equine legs is a complex process due to species characteristics. Based in previous biomechanical study ten horses had iatrogenic metacarpal fractures reduced by external bone fixation. Each animal was evaluated by clinical, laboratorial and radiografic examination till complete recovery. No significant complication were observed, except one animal which was submitted to euthanasia. The method offers appropriate stability for bone healing.

The C4-pathway of C-fixation in Spinacea oleracea. Pt. 1

International Nuclear Information System (INIS)

Boecher, M.; Kluge, M.

1977-01-01

Spinach leaf slices readily fix 14 C supplied from a suspension medium. The pattern of label distribution after 14 C-fixation in the light depends on the pH of the suspension medium. In the range of pH 3.5 leaf slices show labelling patterns of the C 3 type as do intact leaves or leaf slices incubated with 14 CO 2 in a gas cuvette. In contrast, if the tissue slices were suspended at pH 7.5 substantially more label appears in malate and other compounds of the C 4 -pathway. Under these conditions also the malate content of the tissue increases. The addition of NaHCO 3 at pH 3.5 increases the rate of C-fixation and nearly the whole fixed carbon is metabolized in the Calvin-cycle. The C-fixation is also increased, if NaHCO 3 is added at pH 7.5. Here both, the C 3 - and the C 4 -pathway contribute to an enhancement of the C-fixation. It is assumed, that increasing amounts of bicarbonate (substrate of PEP carboxylase) become available to the cells when the pH of the external medium is raised. This could increase an operation of the C 4 -pathway of C-fixation. This view is supported by the finding, that in contrast to low pH, the C-fixation at high pH results in a dominant labelling of the C 4 -atoms of malate. (orig.) [de

Flanged Intrascleral Intraocular Lens Fixation with Double-Needle Technique.

Science.gov (United States)

Yamane, Shin; Sato, Shimpei; Maruyama-Inoue, Maiko; Kadonosono, Kazuaki

2017-08-01

To report the clinical outcomes of a new technique for transconjunctival intrascleral fixation of an intraocular lens (IOL). Prospective, noncomparative, interventional case series. One hundred eyes of 97 consecutive patients with aphakia, dislocated IOL, or subluxated crystalline lens who underwent posterior chamber sutureless implantation of an IOL were studied. Two angled incisions parallel to the limbus were made by 30-gauge thin-wall needles. Haptics of an IOL were externalized with the needles and cauterized to make a flange of the haptics. The flange of the haptics were pushed back and fixed into the scleral tunnels. Best-corrected visual acuity (VA), corneal endothelial cell density, IOL tilt, and complications were determined. The IOLs were fixed with exact centration and axial stability. The mean preoperative best-corrected VA was 0.25 logarithm of the minimum angle of resolution (logMAR) units; after surgery, it improved significantly to 0.11 logMAR, 0.09 logMAR, 0.12 logMAR, and 0.04 logMAR at 6, 12, 24, and 36 months, respectively (P IOL tilt was 3.4°±2.5°. The postoperative complications included iris capture by the IOL in 8 eyes (8%), vitreous hemorrhage in 5 eyes (5%), and cystoid macular edema in 1 eye (1%). There were no incidents of postoperative retinal detachment, endophthalmitis, or IOL dislocation. We have developed a new technique for intrascleral IOL fixation. The flanged IOL fixation technique is a simple and minimally invasive method for achieving good IOL fixation with firm haptic fixation. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

REVISION ANKLE SYNDESMOSIS FIXATION - FUNCTIONAL OUTCOME AFTER TIGHTROPE ® FIXATION

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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.

Effect of repeated sterilization by different methods on strength of carbon fiber rods used in external fixator systems.

Science.gov (United States)

Unal, Omer Kays; Poyanli, Oguz Sukru; Unal, Ulku Sur; Mutlu, Hasan Huseyin; Ozkut, Afsar Timucin; Esenkaya, Irfan

2018-05-16

We set out to reveal the effects of repeated sterilization, using different methods, on the carbon fiber rods of external fixator systems. We used a randomized set of forty-four unused, unsterilized, and identical carbon fiber rods (11 × 200 mm), randomly assigned to two groups: unsterilized (US) (4 rods) and sterilized (40 rods). The sterilized rods were divided into two groups, those sterilized in an autoclave (AC) and by hydrogen peroxide (HP). These were further divided into five subgroups based on the number of sterilization repetition to which the fibers were subjected (25-50-75-100-200). A bending test was conducted to measure the maximum bending force (MBF), maximum deflection (MD), flexural strength (FS), maximum bending moment (MBM) and bending rigidity (BR). We also measured the surface roughness of the rods. An increase in the number of sterilization repetition led to a decrease in MBF, MBM, FS, BR, but increased MD and surface roughness (p < 0.01). The effect of the number of sterilization repetition was more prominent in the HP group. This study revealed that the sterilization method and number of sterilization repetition influence the strength of the carbon fiber rods. Increasing the number of sterilization repetition degrades the strength and roughness of the rods.

Malleolar fractures and their ligamentous injury equivalents have similar outcomes in supination-external rotation type IV fractures of the ankle treated by anatomical internal fixation.

Science.gov (United States)

Berkes, M B; Little, M T M; Lazaro, L E; Sculco, P K; Cymerman, R M; Daigl, M; Helfet, D L; Lorich, D G

2012-11-01

It has previously been suggested that among unstable ankle fractures, the presence of a malleolar fracture is associated with a worse outcome than a corresponding ligamentous injury. However, previous studies have included heterogeneous groups of injury. The purpose of this study was to determine whether any specific pattern of bony and/or ligamentous injury among a series of supination-external rotation type IV (SER IV) ankle fractures treated with anatomical fixation was associated with a worse outcome. We analysed a prospective cohort of 108 SER IV ankle fractures with a follow-up of one year. Pre-operative radiographs and MRIs were undertaken to characterise precisely the pattern of injury. Operative treatment included fixation of all malleolar fractures. Post-operative CT was used to assess reduction. The primary and secondary outcome measures were the Foot and Ankle Outcome Score (FAOS) and the range of movement of the ankle. There were no clinically relevant differences between the four possible SER IV fracture pattern groups with regard to the FAOS or range of movement. In this population of strictly defined SER IV ankle injuries, the presence of a malleolar fracture was not associated with a significantly worse clinical outcome than its ligamentous injury counterpart. Other factors inherent to the injury and treatment may play a more important role in predicting outcome.

Hybrid Correlation Energy (HyCE): An Approach Based on Separate Evaluations of Internal and External Components.

Science.gov (United States)

Ivanic, Joseph; Schmidt, Michael W

2018-06-04

A novel hybrid correlation energy (HyCE) approach is proposed that determines the total correlation energy via distinct computation of its internal and external components. This approach evolved from two related studies. First, rigorous assessment of the accuracies and size extensivities of a number of electron correlation methods, that include perturbation theory (PT2), coupled-cluster (CC), configuration interaction (CI), and coupled electron pair approximation (CEPA), shows that the CEPA(0) variant of the latter and triples-corrected CC methods consistently perform very similarly. These findings were obtained by comparison to near full CI results for four small molecules and by charting recovered correlation energies for six steadily growing chain systems. Second, by generating valence virtual orbitals (VVOs) and utilizing the CEPA(0) method, we were able to partition total correlation energies into internal (or nondynamic) and external (or dynamic) parts for the aforementioned six chain systems and a benchmark test bed of 36 molecules. When using triple-ζ basis sets it was found that per orbital internal correlation energies were appreciably larger than per orbital external energies and that the former showed far more chemical variation than the latter. Additionally, accumulations of external correlation energies were seen to proceed smoothly, and somewhat linearly, as the virtual space is gradually increased. Combination of these two studies led to development of the HyCE approach, whereby the internal and external correlation energies are determined separately by CEPA(0)/VVO and PT2/external calculations, respectively. When applied to the six chain systems and the 36-molecule benchmark test set it was found that HyCE energies followed closely those of triples-corrected CC and CEPA(0) while easily outperforming MP2 and CCSD. The success of the HyCE approach is more notable when considering that its cost is only slightly more than MP2 and significantly cheaper

Hydrologic Control on Bacterial Nitrogen Fixation in the Holocene Black Sea

Science.gov (United States)

Fulton, J. M.; Arthur, M. A.; Freeman, K. H.

2008-12-01

Stratified oceans of the Phanerozoic Oceanic Anoxic Events apparently were dominated by bacterial nitrogen fixation. Decreased marine N:P nutrient ratios resulting from increased denitrification and decreased phosphate burial efficiency under anoxic waters drove this nutrient regime. This model is upheld by the presence of cyanobacterial hopanoid biomarkers in sedimentary records and δ15N values indicative of nitrogen fixation. However, in the largest modern redox-stratified marine basin, the Black Sea, bacterial nitrogen fixation seems to be only a minor contributor to the nitrogen cycle. In this study, we use geochemical proxies to evaluate the role of bacterial nitrogen fixation during the deposition of the Holocene Black Sea sapropel, starting 7.8 ka. We report compound-specific nitrogen and carbon stable isotope values of pyropheophytin a, a chlorophyll degradation product, and bacteriochlorophyll e produced by green sulfur bacteria. We also present the surprising finding of scytonemin, a pigment produced only by filamentous cyanobacteria exposed to ultraviolet radiation, in certain intervals in these sediments. In the Holocene, nitrogen fixation in the Black Sea is most prominent during times of reduced river water influx. This directly decreases the external flux of nitrate into the surface waters. Reduced freshwater influx also decreases the volume of low salinity water dispersed around the sea by the Rim Current, allowing the chemocline to shoal along the margins. Previous geochemical studies have described this changing chemocline geometry. The exposure of shallow water sediments to anoxic waters further stimulates nitrogen fixation by releasing more phosphorus to the system. Nitrogen fixation is recorded in the sediments as bulk and compound-specific pyropheophytin a δ15N values near 0 ‰ and -5 ‰, respectively. We have also detected scytonemin in two intervals characterized by especially low δ15N values. This compound suggests abundant filamentous

Is an alcoholic fixative fluid used for manual liquid-based cytology accurate to perform HPV tests?

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Garbar C

2011-12-01

Full Text Available Christian Garbar1, Corinne Mascaux1, Philippe De Graeve2, Philippe Delvenne31Department of Biopathology, Institute Jean Godinot, Reims Cedex, France; 2Centre de Pathologie des Coteaux, Toulouse, France; 3Department of Pathology, University of Liege, Tour de Pathologie, Domaine Universitaire du Sart Tilman, Liège, BelgiumAbstract: In Europe, the alternative centrifuge method of liquid-based cytology is widely used in cervical screening. Turbitec® (Labonord SAS, Templemars, France is a centrifuge method of liquid-based cytology using an alcoholic fixative fluid, Easyfix® (Labonord. It is now well accepted that the association of liquid-based cytology and human papillomavirus test is indissociable of cervical screening. The aim of this work was to demonstrate that Easyfix alcoholic fluid is reliable to perform Hybrid Capture® 2 (QIAGEN SAS, Courtaboeuf, France. In this study, 75 patients with colposcopy for cervical lesions served as gold standard. A sample was collected, at random, for Easyfix fixative cytological fluid and for Digene Cervical Sampler (QIAGEN. The results of Hybrid Capture 2 (with relative light unit >1 showed no statistical difference, a positive Spearman’s correlation (r = 0.82, P < 0.0001, and a kappa value of 0.87 (excellent agreement between the two fluids. It was concluded that Easyfix is accurate to use in human papillomavirus tests with Hybrid Capture 2.Keywords: human papillomavirus, hybrid capture 2, Turbitec®, cervix cytology, liquid-based cytology

Smaller Fixation Target Size Is Associated with More Stable Fixation and Less Variance in Threshold Sensitivity.

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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.

N₂-fixation and residual N effect of four legume species and four companion grass species

DEFF Research Database (Denmark)

Rasmussen, Jim; Søegaard, Karen; Pirhofer-Walzl, Karin

2012-01-01

and climatic conditions. We conducted a field experiment on a sandy soil at two nitrogen levels with seven two-species forage mixtures: alfalfa, bird's-foot trefoil, red clover, or white clover in mixture with perennial ryegrass, and white clover in mixture with meadow fescue, timothy, or hybrid ryegrass. We...... found high N2-fixation of more than 300 kg N ha-1 from both red clover and alfalfa even when the two mixtures received 300 kg total-N ha-1 in cattle slurry. The addition of cattle slurry N fertilizer lowered N2-fixation for white clover and red clover as expected, but for bird's-foot trefoil and alfalfa...... no changes in the proportion of N derived from N2-fixation was observed. We conclude that the competition for available soil N from perennial ryegrass in mixture was an important factor for the proportion of N in alfalfa, white clover, and bird's-foot trefoil obtained from N2-fixation. White clover had...

The application of fluorescence in situ hybridization (FISH technique for studying the microbial communities in intestinal tissues of white shrimp (Penaeus vannamei

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Supamattaya, K.

2005-02-01

Full Text Available Fluorescence in situ hybridization technique is very useful for the evaluation of microbial communities in various environments. It is possible to apply this technique to study the intestinal microflora in white shrimp (Penaeus vannamei. Different fixatives and storage temperature were tested in this technique. It was found that fixation with 10% buffered formalin for 12 hours and changed to 70% ethanol shown positive results when compared to the fixation with Davidson's fixative or RF fixative. The best signaling was obtainedfrom the samples which were stored in -20ºC. By using the DNA probe targeted to the Eubacteria domain (EUB338 probe, 5′-GCT GCC TCC CGT AGG AGT-3′ labeled with fluorescein as a hybridizing probe, it was found that most intestinal microflora were aggregated with the intestinal contents, or dispersed in the lumen. There was not evidence of the attachment of the microflora with the intestinal epithelium in this study.

The structure and functioning of Dynastab DK - K fixator (knee joint) and its usefullness in clinical use.

Science.gov (United States)

Deszczyński, J; Karpiński, J; Deszczyńska, H

1999-12-30

The autor describes following stages of research on external fixator Dynastab DK - K (knee joint) with in - built artificial joint enabling physiological range of movement of the knee and the use of the device in functional treatment of articular fractures of the knee. The final clinical prototype of the device was developed according to the results of the experiments with anatomical preparations of knee joints in which the trajectory of the physiological movement of the knee was stated. These observations were used to construct mechanical joint with the range of movement adequate to this of the healthy knee. The positive and negative aspects in DK - K fixator are also described. The fixator was appled in 6 difficult cases of articular fractures of knee with good results.

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.

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)

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

Modification of conservative treatment of heterotopic cervical pregnancy by Foley catheter balloon fixation with cerclage sutures at the level of the external cervical os: a case report

Directory of Open Access Journals (Sweden)

Vujisic Sanja

2010-07-01

Full Text Available Abstract Introduction Conservative treatment of a heterotopic cervical pregnancy was performed with a modification of the fixation of a Foley catheter at the level of the external cervical os, followed by the ligature of the descending cervical branches of the uterine arteries and systemic methotrexate application. Case presentation A 34-year-old Caucasian woman was diagnosed with double gestation after 6 weeks of in vitro fertilization treatment. A gynecological examination and color Doppler ultrasound scan revealed intra-uterine and cervical gestational sacs both containing live fetuses. A Foley catheter balloon was inserted into the cervical canal, inflated and fixed by a cerclage suture at the level of the external cervical os, followed by ligation of the descending cervical branches of the uterine arteries. Systemic methotrexate was applied. Three days after removal of the Foley catheter, an evacuation of the intra-uterine gestational sac was performed. Hemorrhage from the implantation site was controlled immediately and a pregnancy termination was successfully performed. The procedure was uneventful and our patient was discharged with a preserved uterus. Conclusions Conservative treatment of cervical pregnancy using a Foley catheter balloon is more efficacious if the Foley catheter balloon is attached in the correct position with a cerclage suture at the level of the external os, followed by ligation of the descending cervical branches of the uterine arteries, thereby exerting maximal pressure on the bleeding vessels.

Repair of Tibiotarsal Rotation in 7 Chukar Partridges (Alectoris chukar) and 12 Domestic Pigeons (Columba livia domestica) with Type-2 External Skeletal Fixator Intramedullary Pin Tie-in.

Science.gov (United States)

Kaya, Didar Aydin; Özsoy, Serhat

2017-09-01

Rotational deformities of the long bones affect various avian species. Tibiotarsal rotation may cause the leg to deviate up to 180° from the dorsoplantar axis in a matter of days, thus preventing the birds from walking freely and leading to the inability to stand. In this study, tibiotarsal rotation observed in pigeons and partridges was managed by creating a closed fracture in the tibiotarsus and then, following reduction, stabilizing it with an intramedullary tie-in Type 2 external skeletal fixation system. Functional healing was achieved in 12 pigeons (Columba livia domestica; mean healing time, 38 days) and 7 partridges (Alectoris chukar; mean healing time, 40 days). This treatment was successful. In small bird species (<1 kg), this simple and inexpensive surgical intervention may provide a highly effective method for the treatment of rotational deformities.

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

External skeletal fixator intramedullary pin tie-in for the repair of tibiotarsal fractures in raptors: 37 cases (1995-2011).

Science.gov (United States)

Bueno, Irene; Redig, Patrick T; Rendahl, Aaron K

2015-11-15

To evaluate the outcome of the application of an external skeletal fixator intramedullary pin tie-in (TIF) to tibiotarsal fractures in raptors. Retrospective case series. Thirty-four raptors with 37 tibiotarsal fractures. Medical records and radiographs for raptors with tibiotarsal fractures that were treated at The Raptor Center at the University of Minnesota between 1995 and 2011 were reviewed. Descriptive statistics were generated and univariate logistic regression analyses were used to assess whether age, sex, body weight, location and nature of the fracture, and type of surgical reduction were significantly associated with whether the fracture healed following surgical reduction and TIF application. 31 of 37 (84%) tibiotarsal fractures successfully healed following surgical reduction and TIF application. The mean healing time was 38 days (range, 15 to 70 days). None of the variables assessed were significantly associated with whether the tibiotarsal fracture healed. Twenty of the 34 (59%) raptors were eventually rehabilitated and released. Results indicated that most tibiotarsal fractures were successfully managed by surgical reduction and stabilization with a TIF. However, other comorbidities (eg, systemic infections and visual deficits) negatively affected the rehabilitation of raptors and sometimes resulted in euthanasia despite the fact that the tibiotarsal fracture had healed, and those comorbidities, along with the variables evaluated (eg, age, sex, and nature of the fracture), should be used as triage criteria and prognostic indicators.

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.

Legal Obstacles to Comprehensive EU External Security Action

NARCIS (Netherlands)

Blockmans, S.; Spernbauer, M.

2013-01-01

Despite the unification of the EU legal order, the merger of external action objectives and the creation of hybrid coordination structures, the dichotomy between the CFSP and non-CFSP categories of EU external action has been maintained in the Lisbon Treaty. This article considers the legal

Misdiagnosis and management of iatrogenic pseudoaneurysm of vertebral artery after Harms technique of C1-C2 fixation

Directory of Open Access Journals (Sweden)

MIN Li

2012-12-01

Full Text Available 【Abstract】 Harms technique of C1-C2 fixation for atlantoaxial complex becomes more popular due to good fusion rate and low vertebral artery injury (VAI rate. But considering the unique and variable anatomy of atlanto-axial complex, iatrogenic VAI will result in catastrophic con-sequences and provides particular surgical challenges for surgeons. To our knowledge, comparing with iatrogenic VAI in the screw hole, iatrogenic VAI in the “open space” is much rarer during the Harms technique of C1-C2 fixation. In this article, we present a case of iatrogenic vertebral artery pseudoaneurysm after Harms technique of posterior C1-C2 fixation. This case of iatrogenic VAI effectively treated by endovascular coil occlusion and external local compression was initially misdiagnosed as VAI by pedicle screw perforation. It can be concluded that intraoperative or post-operative computed angiography is very helpful to diag-nose the exact site of VAI and the combination of endovascular coil occlusion as well as external local com-pression can further prevent bleeding and abnormal verte-bral artery flow in the pseudoaneurysm. However, patients treated require further follow-up to confirm that there is no recurrence of the pseudoaneurysm. Key words: Vertebral artery; Aneurysm, false; Endovascular procedures

Nanofabrication Yields. Hybridization and Click-Fixation of Polycyclic DNA Nanoassemblies

KAUST Repository

Lundberg, Erik P.

2011-09-27

We demonstrate the stepwise assembly of a fully addressable polycyclic DNA hexagon nanonetwork for the preparation of a four-ring system, one of the biggest networks yet constructed from tripodal building blocks. We find that the yield exhibits a distinct upper level <100%, a fundamental problem of thermodynamic DNA assembly that appears to have been overlooked in the DNA nanotechnology literature. A simplistic model based on a single step-yield parameter y can quantitatively describe the total yield of DNA assemblies in one-pot reactions as Y = yduplex n, with n the number of hybridization steps. Experimental errors introducing deviations from perfect stoichiometry and the thermodynamics of hybridization equilibria contribute to decreasing the value of yduplex (on average y = 0.96 for our 10 base pair hybridization). For the four-ring system (n = 31), the total yield is thus less than 30%, which is clearly unsatisfactory if bigger nanoconstructs of this class are to be designed. Therefore, we introduced site-specific click chemistry for making and purifying robust building blocks for future modular constructs of larger assemblies. Although the present yield of this robust module was only about 10%, it demonstrates a first step toward a general fabrication approach. Interestingly, we find that the click yields follow quantitatively a binomial distribution, the predictability of which indicates the usefulness of preparing pools of pure and robust building blocks in this way. The binomial behavior indicates that there is no interference between the six simultaneous click reactions but that step-yield limiting factors such as topological constraints and Cu(I) catalyst concentration are local and independent. © 2011 American Chemical Society.

Bacterial N2-fixation in mangrove ecosystems: insights from a diazotroph-mangrove interaction.

Science.gov (United States)

Alfaro-Espinoza, Gabriela; Ullrich, Matthias S

2015-01-01

Mangrove forests are highly productive ecosystems but represent low nutrient environments. Nitrogen availability is one of the main factors limiting mangrove growth. Diazotrophs have been identified as key organisms that provide nitrogen to these environments. N2-fixation by such organisms was found to be higher in the mangrove roots than in surrounding rhizosphere. Moreover, previous studies showed that mangroves grew better in the presence of N2-fixers indicating a potentially mutualistic relationship. However, the molecular signals and mechanisms that govern these interactions are still poorly understood. Here we present novel insights in the interaction of a diazotroph with a mangrove species to improve our understanding of the molecular and ecophysiological relationship between these two organisms under controlled conditions. Our results showed that Marinobacterium mangrovicola is a versatile organism capable of competing with other organisms to survive for long periods in mangrove soils. N2-fixation by this bacterium was up-regulated in the presence of mangrove roots, indicating a possible beneficial interaction. The increase in N2-fixation was limited to cells of the exponential growth phase suggesting that N2-fixation differs over the bacterial growth cycle. Bacterial transformants harboring a transcriptional nifH::gusA fusion showed that M. mangrovicola successfully colonized mangrove roots and simultaneously conducted N2-fixation. The colonization process was stimulated by the lack of an external carbon source suggesting a possible mutualistic relationship. M. mangrovicola represents an interesting genetically accessible diazotroph, which colonize mangrove roots and exhibit higher N2-fixation in the presence of mangrove roots. Consequently, we propose this microorganism as a tool to study molecular interactions between N2-fixers and mangrove plants and to better understand how changes in the environment could impact these important and relatively unknown

Dimensional structure of DSM-5 posttraumatic stress symptoms: support for a hybrid Anhedonia and Externalizing Behaviors model.

Science.gov (United States)

Armour, Cherie; Tsai, Jack; Durham, Tory A; Charak, Ruby; Biehn, Tracey L; Elhai, Jon D; Pietrzak, Robert H

2015-02-01

Several revisions to the symptom clusters of posttraumatic stress disorder (PTSD) have been made in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Central to the focus of this study was the revision of PTSD's tripartite structure in DSM-IV into four symptom clusters in DSM-5. Emerging confirmatory factor analytic (CFA) studies have suggested that DSM-5 PTSD symptoms may be best represented by one of two 6-factor models: (1) an Externalizing Behaviors model characterized by a factor which combines the irritability/anger and self-destructive/reckless behavior items; and (2) an Anhedonia model characterized by items of loss of interest, detachment, and restricted affect. The current study conducted CFAs of DSM-5 PTSD symptoms assessed using the PTSD Checklist for DSM-5 (PCL-5) in two independent and diverse trauma-exposed samples of a nationally representative sample of 1484 U.S. veterans and a sample of 497 Midwestern U.S. university undergraduate students. Relative fits of the DSM-5 model, the DSM-5 Dysphoria model, the DSM-5 Dysphoric Arousal model, the two 6-factor models, and a newly proposed 7-factor Hybrid model, which consolidates the two 6-factor models, were evaluated. Results revealed that, in both samples, both 6-factor models provided significantly better fit than the 4-factor DSM-5 model, the DSM-5 Dysphoria model and the DSM-5 Dysphoric Arousal model. Further, the 7-factor Hybrid model, which incorporates key features of both 6-factor models and is comprised of re-experiencing, avoidance, negative affect, anhedonia, externalizing behaviors, and anxious and dysphoric arousal symptom clusters, provided superior fit to the data in both samples. Results are discussed in light of theoretical and empirical support for the latent structure of DSM-5 PTSD symptoms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of the externalities of biomass energy for electricity production

Energy Technology Data Exchange (ETDEWEB)

Linares, P; Leal, J; Saez, R M

1996-10-01

This study presents a methodology for the quantification of the socioeconomic and environmental externalities of the biomass fuel cycle. It is based on the one developed by the ExternE Project of the European Commission, based in turn in the damage function approach, and which has been extended and modified for a better adaptation to biomass energy systems. The methodology has been applied to a 20 MW biomass power plant, fueled by Cynara cardunculus, in southern Spain. The externalities addressed have been macroeconomic effects, employment, CO{sub 2}, fixation, erosion, and non-point source pollution. The results obtained should be considered only as subtotals, since there are still other externalities to be quantified. anyway, and in spite of the uncertainty existing, these results suggest that total cost (those including internal and external costs) of biomass energy are lower than those of conventional energy sources, what, if taken into account, would make biomass more competitive than it is now. (Author)

Aphotic N2 fixation along an oligotrophic to ultraoligotrophic transect in the western tropical South Pacific Ocean

Science.gov (United States)

Benavides, Mar; Shoemaker, Katyanne M.; Moisander, Pia H.; Niggemann, Jutta; Dittmar, Thorsten; Duhamel, Solange; Grosso, Olivier; Pujo-Pay, Mireille; Hélias-Nunige, Sandra; Fumenia, Alain; Bonnet, Sophie

2018-05-01

The western tropical South Pacific (WTSP) Ocean has been recognized as a global hot spot of dinitrogen (N2) fixation. Here, as in other marine environments across the oceans, N2 fixation studies have focused on the sunlit layer. However, studies have confirmed the importance of aphotic N2 fixation activity, although until now only one had been performed in the WTSP. In order to increase our knowledge of aphotic N2 fixation in the WTSP, we measured N2 fixation rates and identified diazotrophic phylotypes in the mesopelagic layer along a transect spanning from New Caledonia to French Polynesia. Because non-cyanobacterial diazotrophs presumably need external dissolved organic matter (DOM) sources for their nutrition, we also identified DOM compounds using Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) with the aim of searching for relationships between the composition of DOM and non-cyanobacterial N2 fixation in the aphotic ocean. N2 fixation rates were low (average 0.63 ± 0.07 nmol N L-1 d-1) but consistently detected across all depths and stations, representing ˜ 6-88 % of photic N2 fixation. N2 fixation rates were not significantly correlated with DOM compounds. The analysis of nifH gene amplicons revealed a wide diversity of non-cyanobacterial diazotrophs, mostly matching clusters 1 and 3. Interestingly, a distinct phylotype from the major nifH subcluster 1G dominated at 650 dbar, coinciding with the oxygenated Subantarctic Mode Water (SAMW). This consistent pattern suggests that the distribution of aphotic diazotroph communities is to some extent controlled by water mass structure. While the data available are still too scarce to elucidate the distribution and controls of mesopelagic non-cyanobacterial diazotrophs in the WTSP, their prevalence in the mesopelagic layer and the consistent detection of active N2 fixation activity at all depths sampled during our study suggest that aphotic N2 fixation may contribute significantly to fixed

Predictors of Time to Union After Operative Fixation of Closed Ankle Fractures.

Science.gov (United States)

Matson, Andrew P; Hamid, Kamran S; Adams, Samuel B

2017-08-01

Ankle fractures are common and represent a significant burden to society. We aim to report the rate of union as determined by clinical and radiographic data, and to identify factors that predict time to union. A cohort of 112 consecutive patients with isolated, closed, operative malleolar ankle fractures treated with open reduction and internal fixation was retrospectively reviewed for time to clinical union. Clinical union was defined based on radiographic and clinical parameters, and delayed union was defined by time to union >12 weeks. Injury characteristics, patient factors and treatment variables were recorded, and statistical techniques employed included the Chi-square test, the Student's T-test, and multivariate linear regression modeling. Forty-two (37.5%) of patients who achieved union did so in less than 12 weeks, and 69 (61.6%) of these patients demonstrated delayed union at a mean of 16.7 weeks (range, 12.1-26.7 weeks), and the remaining patient required revision surgery. Factors associated with higher rates of delayed union or increased time to union included tobacco use, bimalleolar fixation, and high energy mechanism (all punion were BMI, dislocation of the tibiotalar joint, external fixation for initial stabilization and delay of definitive management (all punion following open reduction and internal fixation of closed ankle fractures. These findings should assist with patient counseling, and help guide the provider when considering adjunctive therapies that promote bone healing. Prognostic, Level IV: Case series.

Numerical analysis of stiffener for hybrid drive unite

Directory of Open Access Journals (Sweden)

Jakubovičová Lenka

2018-01-01

Full Text Available The matter of this article is a stress-strain analysis of hybrid drive prototype unit connected directly to convention Concrete Transit Mixer Gearbox. The unite was developed with intention to do field test on existing convection machines with possibility to use existing interfaces. The hybrid drive unit consists from electric and hydrostatic motor connected through addition mechanical transmission gearbox. The question is if today standard interface is good enough or need additional support a “stiffener”. Two engineering design were analysed. The first one includes using the stiffener to fixate the construction of hybrid drive unite connected to the planetary gear. The second one is without the stiffener. For strain-stress analysis, a finite element software ANSYS Workbench was used.

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 ...

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, ...

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.

One visual search, many memory searches: An eye-tracking investigation of hybrid search.

Science.gov (United States)

Drew, Trafton; Boettcher, Sage E P; Wolfe, Jeremy M

2017-09-01

Suppose you go to the supermarket with a shopping list of 10 items held in memory. Your shopping expedition can be seen as a combination of visual search and memory search. This is known as "hybrid search." There is a growing interest in understanding how hybrid search tasks are accomplished. We used eye tracking to examine how manipulating the number of possible targets (the memory set size [MSS]) changes how observers (Os) search. We found that dwell time on each distractor increased with MSS, suggesting a memory search was being executed each time a new distractor was fixated. Meanwhile, although the rate of refixation increased with MSS, it was not nearly enough to suggest a strategy that involves repeatedly searching visual space for subgroups of the target set. These data provide a clear demonstration that hybrid search tasks are carried out via a "one visual search, many memory searches" heuristic in which Os examine items in the visual array once with a very low rate of refixations. For each item selected, Os activate a memory search that produces logarithmic response time increases with increased MSS. Furthermore, the percentage of distractors fixated was strongly modulated by the MSS: More items in the MSS led to a higher percentage of fixated distractors. Searching for more potential targets appears to significantly alter how Os approach the task, ultimately resulting in more eye movements and longer response times.

Gating based on internal/external signals with dynamic correlation updates

International Nuclear Information System (INIS)

Wu Huanmei; Zhao Qingya; Berbeco, Ross I; Nishioka, Seiko; Shirato, Hiroki; Jiang, Steve B

2008-01-01

Precise localization of mobile tumor positions in real time is critical to the success of gated radiotherapy. Tumor positions are usually derived from either internal or external surrogates. Fluoroscopic gating based on internal surrogates, such as implanted fiducial markers, is accurate however requiring a large amount of imaging dose. Gating based on external surrogates, such as patient abdominal surface motion, is non-invasive however less accurate due to the uncertainty in the correlation between tumor location and external surrogates. To address these complications, we propose to investigate an approach based on hybrid gating with dynamic internal/external correlation updates. In this approach, the external signal is acquired at high frequency (such as 30 Hz) while the internal signal is sparsely acquired (such as 0.5 Hz or less). The internal signal is used to validate and update the internal/external correlation during treatment. Tumor positions are derived from the external signal based on the newly updated correlation. Two dynamic correlation updating algorithms are introduced. One is based on the motion amplitude and the other is based on the motion phase. Nine patients with synchronized internal/external motion signals are simulated retrospectively to evaluate the effectiveness of hybrid gating. The influences of different clinical conditions on hybrid gating, such as the size of gating windows, the optimal timing for internal signal acquisition and the acquisition frequency are investigated. The results demonstrate that dynamically updating the internal/external correlation in or around the gating window will reduce false positive with relatively diminished treatment efficiency. This improvement will benefit patients with mobile tumors, especially greater for early stage lung cancers, for which the tumors are less attached or freely floating in the lung.

Gating based on internal/external signals with dynamic correlation updates

Energy Technology Data Exchange (ETDEWEB)

Wu Huanmei [Purdue School of Engineering and Technology, Indiana University School of Informatics, IUPUI, Indianapolis, IN (United States); Zhao Qingya [School of Health Sciences, Purdue University, West Lafayette, IN (United States); Berbeco, Ross I [Department of Radiation Oncology, Dana-Farber/Brigham and Womens Cancer Center and Harvard Medical School, Boston, MA (United States); Nishioka, Seiko [NTT East-Japan Sapporo Hospital, Sapporo (Japan); Shirato, Hiroki [Hokkaido University Graduate School of Medicine, Sapporo (Japan); Jiang, Steve B [Department of Radiation Oncology, School of Medicine, University of California, San Diego, CA (United States)], E-mail: hw9@iupui.edu, E-mail: sbjiang@ucsd.edu

2008-12-21

Precise localization of mobile tumor positions in real time is critical to the success of gated radiotherapy. Tumor positions are usually derived from either internal or external surrogates. Fluoroscopic gating based on internal surrogates, such as implanted fiducial markers, is accurate however requiring a large amount of imaging dose. Gating based on external surrogates, such as patient abdominal surface motion, is non-invasive however less accurate due to the uncertainty in the correlation between tumor location and external surrogates. To address these complications, we propose to investigate an approach based on hybrid gating with dynamic internal/external correlation updates. In this approach, the external signal is acquired at high frequency (such as 30 Hz) while the internal signal is sparsely acquired (such as 0.5 Hz or less). The internal signal is used to validate and update the internal/external correlation during treatment. Tumor positions are derived from the external signal based on the newly updated correlation. Two dynamic correlation updating algorithms are introduced. One is based on the motion amplitude and the other is based on the motion phase. Nine patients with synchronized internal/external motion signals are simulated retrospectively to evaluate the effectiveness of hybrid gating. The influences of different clinical conditions on hybrid gating, such as the size of gating windows, the optimal timing for internal signal acquisition and the acquisition frequency are investigated. The results demonstrate that dynamically updating the internal/external correlation in or around the gating window will reduce false positive with relatively diminished treatment efficiency. This improvement will benefit patients with mobile tumors, especially greater for early stage lung cancers, for which the tumors are less attached or freely floating in the lung.

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.

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.

Hip- and knee-strength assessments using a hand-held dynamometer with external belt-fixation are inter-tester reliable

DEFF Research Database (Denmark)

Thorborg, Kristian; Bandholm, Thomas; Hölmich, Per

2013-01-01

PURPOSE: In football, ice-hockey, and track and field, injuries have been predicted, and hip- and knee-strength deficits quantified using hand-held dynamometry (HHD). However, systematic bias exists when testers of different sex and strength perform the measurements. Belt-fixation of the dynamome...

Cluster synchronization in community network with hybrid coupling

International Nuclear Information System (INIS)

Yang, Lixin; Jiang, Jun; Liu, Xiaojun

2016-01-01

Highlights: • A community network model with hybrid coupling is proposed. • Control scheme is designed via combining adaptive external coupling strength and feedback control. • The influence of topology structure on synchronization of community network is discussed. - Abstract: A general model of community network with hybrid coupling is proposed in this paper. In the community network model with hybrid coupling, the inner connections are in the same type of coupling within the same community and in different types of coupling in different communities. The connections between different pair of communities are also nonidentical. Cluster synchronization of community network with hybrid coupling is investigated via adaptive couplings control scheme. Effective controllers are designed for constructing an effective control scheme and adjusting automatically the adaptive external coupling strength by taking external coupling strength as adaptive variables on a small fraction of network edges. Moreover, the impact of the topology on the synchronizability of community network is investigated. The numerical results reveal that the number of links between communities and the degree of the connector nodes have significant effects on the synchronization performance.

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.

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.

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.

Fixation of osteochondral fractures in rabbit knees. A comparison of Kirschner wires, fibrin sealant, and polydioxanone pins.

Science.gov (United States)

Plaga, B R; Royster, R M; Donigian, A M; Wright, G B; Caskey, P M

1992-03-01

We compared fibrin sealant, polydioxanone (PDS) pins and Kirschner wires in the fixation of osteochondral fractures in rabbit knees. Standardised osteochondral fractures of the right medial femoral condyle were made in 56 adult New Zealand white rabbits. There were equal groups of control knees, and those which had Kirschner-wire, fibrin-sealant or PDS-pin fixation. No external immobilisation was used. One animal from each group was killed at two, three and four weeks. The remaining rabbits were killed at six weeks. A fracture which healed with less than 1 mm of displacement was considered a success. There was successful healing in 29% of the control group, in all of the Kirschner-wire group, in 50% of the fibrin-sealant group, and in 86% of the PDS-pin group. The use of PDS pins appears to be a reliable alternative to the use of metal in the fixation of osteochondral fractures in rabbits.

Aphotic N2 fixation along an oligotrophic to ultraoligotrophic transect in the western tropical South Pacific Ocean

Directory of Open Access Journals (Sweden)

M. Benavides

2018-05-01

Full Text Available The western tropical South Pacific (WTSP Ocean has been recognized as a global hot spot of dinitrogen (N2 fixation. Here, as in other marine environments across the oceans, N2 fixation studies have focused on the sunlit layer. However, studies have confirmed the importance of aphotic N2 fixation activity, although until now only one had been performed in the WTSP. In order to increase our knowledge of aphotic N2 fixation in the WTSP, we measured N2 fixation rates and identified diazotrophic phylotypes in the mesopelagic layer along a transect spanning from New Caledonia to French Polynesia. Because non-cyanobacterial diazotrophs presumably need external dissolved organic matter (DOM sources for their nutrition, we also identified DOM compounds using Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS with the aim of searching for relationships between the composition of DOM and non-cyanobacterial N2 fixation in the aphotic ocean. N2 fixation rates were low (average 0.63 ± 0.07 nmol N L−1 d−1 but consistently detected across all depths and stations, representing ∼ 6–88 % of photic N2 fixation. N2 fixation rates were not significantly correlated with DOM compounds. The analysis of nifH gene amplicons revealed a wide diversity of non-cyanobacterial diazotrophs, mostly matching clusters 1 and 3. Interestingly, a distinct phylotype from the major nifH subcluster 1G dominated at 650 dbar, coinciding with the oxygenated Subantarctic Mode Water (SAMW. This consistent pattern suggests that the distribution of aphotic diazotroph communities is to some extent controlled by water mass structure. While the data available are still too scarce to elucidate the distribution and controls of mesopelagic non-cyanobacterial diazotrophs in the WTSP, their prevalence in the mesopelagic layer and the consistent detection of active N2 fixation activity at all depths sampled during our study suggest that aphotic N2

Electrical potential-assisted DNA hybridization. How to mitigate electrostatics for surface DNA hybridization.

Science.gov (United States)

Tymoczko, Jakub; Schuhmann, Wolfgang; Gebala, Magdalena

2014-12-24

Surface-confined DNA hybridization reactions are sensitive to the number and identity of DNA capture probes and experimental conditions such as the nature and the ionic strength of the electrolyte solution. When the surface probe density is high or the concentration of bulk ions is much lower than the concentration of ions within the DNA layer, hybridization is significantly slowed down or does not proceed at all. However, high-density DNA monolayers are attractive for designing high-sensitivity DNA sensors. Thus, circumventing sluggish DNA hybridization on such interfaces allows a high surface concentration of target DNA and improved signal/noise ratio. We present potential-assisted hybridization as a strategy in which an external voltage is applied to the ssDNA-modified interface during the hybridization process. Results show that a significant enhancement of hybridization can be achieved using this approach.

Alignment After Intramedullary Nailing of Distal Tibia Fractures Without Fibula Fixation.

Science.gov (United States)

De Giacomo, Anthony F; Tornetta, Paul

2016-10-01

To evaluate the efficacy of intramedullary nailing of distal tibia fractures using modern techniques, without fibula fixation, in obtaining and maintaining alignment. Retrospective case review. Level-I academic trauma center. One hundred thirty-two consecutive patients with distal tibia fractures. Intramedullary nail of distal tibia fracture, without fibula fixation, was performed in consecutive patients using modern reduction techniques. Malalignment and malunion were defined as >5 degrees of varus/valgus angulation or anterior/posterior angulation on the initial postoperative or final anteroposterior and lateral x-rays. There were 122 consecutive patients (86 men and 36 women) 16-93 years of age (average, 43 years) with 36 (30%) open and 85 (70%) closed fractures with complete follow-up. Mechanism of injury did not predict the presence or level of fibula fracture. Upon presentation, varus/valgus and procurvatum/recurvatum angulation was greatest when the fibula was fractured at the level of the tibia fracture (P = 0.001 and 0.028). The most common intraoperative reduction aids were nailing in relative extension, transfixion external fixation, and clamps at the fracture site. The OTA fracture type or level/presence of fibula fracture did not influence malalignment (P = 0.86 and 0.66), malunion (P = 0.81 and 0.79), or the change in alignment during union, which averaged 0.9 degrees. We found an overall low rate of both malalignment (2%) and malunion (3%) after intramedullary nailing of distal tibial shaft fracture without fibula fixation. We conclude that when modern nailing techniques are used, which allow for confirmation of reduction by visualization in fluoroscopy, from nail placement to distal interlocking, fibula fixation is not necessary to obtain or maintain alignment. Furthermore, standard 2 medial to lateral screws distally afford adequate stability to hold the reduction during union with a 0.9-degree difference in the initial postoperative and final

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

Directory of Open Access Journals (Sweden)

Alessandro Moraes Leotte

2004-12-01

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

Dinitrogen fixation in aphotic oxygenated marine environments

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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.

[Surgical treatment of pronation and supination external rotation trimalleolar fractures].

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Xu, Ye-qing; Zhan, Bei-lei; He, Fei-xiong; Wei, Hong-da

2008-04-01

To explore the operative method and its clinical effects of pronation and supination external rotation trimalleolar fractures. From March 2000 to July 2006,42 patients of the pronation and supination external rotation trimalleolar fractures treated with open reduction and internal fixation. Thirty-one were males and 11 were females,with an average age of 40.5 years (from 19 to 76 years). Four cases were open fractures and 38 cases close fractures. The fractures were classified as pronation-external rotation (grade IV) injury in 18 cases and supination-external rotation (grade IV)in 24 cases according to the system of Lauge-Hansen. The time of injury to operation was 2 hours to 27 days. The medial, lateral and posterior malleolus were exposed by standard anteromedial and Gatellier-Chastang approaches. The reduction and internal fixation started with the posterior,then the medial and the lateral malleolus and distal tibiofibular syndesmosis in sequence. The anteroposterior, lateral and mostise X-ray films were taken after operation. All the patients were followed up for an average time of 13.5 months(from 6 to 24 months). The time of union was from 12 to 16 weeks. The results were excellent in 20,good in 16, fair in 4 and poor in 2 cases according to Baird-Jackson ankle scoring system based on pain, stability, walking ability,range of motion and radiological manifestations. The excellent and good rate was 85.7%. There were no infection,malunion and nonunion of the fractures except that the inserted screw to distal tibiofibular syndesmosis was broken in 1 case. The key of operative treatment is to restore the anatomy of ankle and to regain the ankle function maximally.

Permanganate Fixation of Plant Cells

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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

Long-term results of various therapy concepts in severe pilon fractures.

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Koulouvaris, Panagiotis; Stafylas, Kosmas; Mitsionis, Gregory; Vekris, Marios; Mavrodontidis, Alexandros; Xenakis, Theodore

2007-07-01

Intra-articular fractures of the tibia plafond are among the most challenging of orthopaedic problems. This is a retrospective case-control study of surgically treated pilon fractures which was undertaken to compare the internal fixation with the two external fixation methods. This is a case-control study of 55 patients with 55 pilon fractures. There were 36 type C and 19 type B. Of these fractures, 24 were open and 31 closed. Three surgical protocols were used. In 20 patients, Group A, a half pin external fixator with ankle spanning was performed. The mean age of patients was 42.0 years (22.0-74.0), SD 14.1 and the mean follow-up was 77.7 months (38.0-132.0), SD 25.4. In 22 patients, Group B, a single ankle sparring ring hybrid external fixator under a small arthrotomy was performed. The mean age of patients was 48.4 years (28.0-76.0), SD 12.4 and mean follow-up was 67.9 months (36.0-132.0), SD 27.8. In 13 patients, Group C, a two-staged internal fixation was performed. The mean age was 45.6 years (30.0-66.0), SD 9.7 and the mean follow-up was 78.6 months (55.0-132.0), SD 25.4. We addressed the dissimilarity of the type of fracture in each group performing supplementary stratified analyses within each fracture type group. Group A had union in 6.9 months, group B in 5.6 months and group C in 5.1 months; P = 0.009. Six patients (Group A), two (Group B), and one (Group C) had limitation of ankle motion; P = 0.47. One patient from group C developed infection and the plate was removed. Four patients (Group A), one (Group B), and one (Group C) have developed posttraumatic arthritis (loss of joint space and pain); P = 0.25. Seven patients from Group A have reduced their activities; P = 0.004. In stratified statistical analysis by type of fracture, the associations noted for both fracture groups combined were also noted separately within each fracture group. In this long term follow-up study, the two-staged internal fixation and the hybrid fixation with small arthrotomy

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

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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.

EEG Negativity in Fixations Used for Gaze-Based Control: Toward Converting Intentions into Actions with an Eye-Brain-Computer Interface

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Shishkin, Sergei L.; Nuzhdin, Yuri O.; Svirin, Evgeny P.; Trofimov, Alexander G.; Fedorova, Anastasia A.; Kozyrskiy, Bogdan L.; Velichkovsky, Boris M.

2016-01-01

We usually look at an object when we are going to manipulate it. Thus, eye tracking can be used to communicate intended actions. An effective human-machine interface, however, should be able to differentiate intentional and spontaneous eye movements. We report an electroencephalogram (EEG) marker that differentiates gaze fixations used for control from spontaneous fixations involved in visual exploration. Eight healthy participants played a game with their eye movements only. Their gaze-synchronized EEG data (fixation-related potentials, FRPs) were collected during game's control-on and control-off conditions. A slow negative wave with a maximum in the parietooccipital region was present in each participant's averaged FRPs in the control-on conditions and was absent or had much lower amplitude in the control-off condition. This wave was similar but not identical to stimulus-preceding negativity, a slow negative wave that can be observed during feedback expectation. Classification of intentional vs. spontaneous fixations was based on amplitude features from 13 EEG channels using 300 ms length segments free from electrooculogram contamination (200–500 ms relative to the fixation onset). For the first fixations in the fixation triplets required to make moves in the game, classified against control-off data, a committee of greedy classifiers provided 0.90 ± 0.07 specificity and 0.38 ± 0.14 sensitivity. Similar (slightly lower) results were obtained for the shrinkage Linear Discriminate Analysis (LDA) classifier. The second and third fixations in the triplets were classified at lower rate. We expect that, with improved feature sets and classifiers, a hybrid dwell-based Eye-Brain-Computer Interface (EBCI) can be built using the FRP difference between the intended and spontaneous fixations. If this direction of BCI development will be successful, such a multimodal interface may improve the fluency of interaction and can possibly become the basis for a new input device

EEG Negativity in Fixations Used for Gaze-Based Control: Toward Converting Intentions into Actions with an Eye-Brain-Computer Interface

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Sergei L. Shishkin

2016-11-01

Full Text Available We usually look at an object when we are going to manipulate it. Thus, eye tracking can be used to communicate intended actions. An effective human-machine interface, however, should be able to differentiate intentional and spontaneous eye movements. We report an electroencephalogram (EEG marker that differentiates gaze fixations used for control from spontaneous fixations involved in visual exploration. Eight healthy participants played a game with their eye movements only. Their gaze-synchronized EEG data (fixation-related potentials, FRPs were collected during game’s control-on and control-off conditions. A slow negative wave with a maximum in the parietooccipital region was present in each participant’s averaged FRPs in the control-on conditions and was absent or had much lower amplitude in the control-off condition. This wave was similar but not identical to stimulus-preceding negativity, a slow negative wave that can be observed during feedback expectation. Classification of intentional vs. spontaneous fixations was based on amplitude features from 13 EEG channels using 300 ms length segments free from electrooculogram contamination (200..500 ms relative to the fixation onset. For the first fixations in the fixation triplets required to make moves in the game, classified against control-off data, a committee of greedy classifiers provided 0.90 ± 0.07 specificity and 0.38 ± 0.14 sensitivity. Similar (slightly lower results were obtained for the shrinkage LDA classifier. The second and third fixations in the triplets were classified at lower rate. We expect that, with improved feature sets and classifiers, a hybrid dwell-based Eye-Brain-Computer Interface (EBCI can be built using the FRP difference between the intended and spontaneous fixations. If this direction of BCI development will be successful, such a multimodal interface may improve the fluency of interaction and can possibly become the basis for a new input device for

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

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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.

Customizable rigid head fixation for infants: technical note.

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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.

Fewer complications with bolt-connected than tunneled external ventricular drainage

DEFF Research Database (Denmark)

Jensen, Torben Slott; Carlsen, Jakob Gram; Poulsen, Frantz Rom

2016-01-01

BACKGROUND: Ventriculostomy/external ventricular drain (EVD) is a common neurosurgical procedure. Various techniques are used to fixate the drain and the objective of this study was, in a retrospective setting, to compare the incidence of complications when using bolt-connected EVD (BC-EVD) versus...... tunneled EVD (T-EVD). METHODS: All patients subjected to an EVD performed through a new burr hole from 2009 through 2010 at two Depts. of Neurosurgery in Denmark (Odense and Aarhus) were retrospectively identified. Patient files were evaluated for EVD fixation technique (tunneled or bolt-connected EVD...... %), compared to the bolt-connected EVD group (6.5 %). There was no significant difference in infection rates. CONCLUSIONS: Tunneled EVD has a relatively high frequency of complications leading to reinsertion. The use of Bolt-connected EVD technique can lower this frequency significantly. The number needed...

[Missed diagnosis of hiding posterior marginal fracture of ankle with pronation-external rotation type and its treatment].

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Wang, Jia; Zhang, Yun-Tong; Zhang, Chun-Cai; Tang, Yang

2014-01-01

To analyze causes of missed diagnosis of hiding post-malleolar fractures in treating ankle joint fractures of pronation-external rotation type according to Lauge-Hansen classification and assess its medium-term outcomes. Among 103 patients with ankle joint fracture of pronation-external rotation type treated from March 2002 to June 2010,9 patients were missed diagnosis,including 6 males and 3 females,with a mean age of 35.2 years old (ranged, 18 to 55 years old) . Four patients were diagnosed during operation, 2 patients were diagnosed 2 or 3 days after first surgery and 3 patients came from other hospital. All the patients were treated remedially with lag screws and lock plates internal fixation. After operation,ankle joint function was evaluated according to American Orthopaedic Foot and Ankle Society (AOFAS). All the 9 patients were followed up, and the duration ranged from 14 to 30 months (averaged, 17 months). No incision infection was found, and all incision healed at the first stage. At the latest follow-up, AOFAS was 83.0 +/- 4.4, the score of 4 patients diagnosed during operation was 85.0 +/- 2.9, and the score of 5 patients treated by secondary operation was 81.0 +/- 5.3. All the patients got fracture union observed by X-ray at a mean time of 2.2 months after operation. There were no complications such as internal fixation loosing, broken and vascular or nerve injuries. Ankle joint fracture of pronation-external rotation type may be combined with hiding post-malleolar fractures. So to patients with ankle joint fracture of pronation-external rotation type, lateral X-ray should be read carefully, and if necessary, CT or MRI examination should be performed. If adding lateral X-ray examination after reduction of exterior and interior ankle joint fixation, the missed diagnosis may be avoided.

Dissolved Organic Matter Influences N2 Fixation in the New Caledonian Lagoon (Western Tropical South Pacific

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Mar Benavides

2018-03-01

Full Text Available Specialized prokaryotes performing biological dinitrogen (N2 fixation (“diazotrophs” provide an important source of fixed nitrogen in oligotrophic marine ecosystems such as tropical and subtropical oceans. In these waters, cyanobacterial photosynthetic diazotrophs are well known to be abundant and active, yet the role and contribution of non-cyanobacterial diazotrophs are currently unclear. The latter are not photosynthetic (here called “heterotrophic” and hence require external sources of organic matter to sustain N2 fixation. Here we added the photosynthesis inhibitor 3-(3,4-dichlorophenyl-1,1-dimethylurea (DCMU to estimate the N2 fixation potential of heterotrophic diazotrophs as compared to autotrophic ones. Additionally, we explored the influence of dissolved organic matter (DOM on these diazotrophs along a coast to open ocean gradient in the surface waters of a subtropical coral lagoon (New Caledonia. Total N2 fixation (samples not amended with DCMU ranged from 0.66 to 1.32 nmol N L−1 d−1. The addition of DCMU reduced N2 fixation by >90%, suggesting that the contribution of heterotrophic diazotrophs to overall N2 fixation activity was minor in this environment. Higher contribution of heterotrophic diazotrophs occurred in stations closer to the shore and coincided with the decreasing lability of DOM, as shown by various colored DOM and fluorescent DOM (CDOM and FDOM indices. We tested the response of diazotrophs (in terms of nifH gene expression and bulk N2 fixation rates upon the addition of a mix of carbohydrates (“DOC” treatment, amino acids (“DON” treatment, and phosphonates and phosphomonesters (“DOP” treatment. While nifH expression increased significantly in Trichodesmium exposed to the DOC treatment, bulk N2 fixation rates increased significantly only in the DOP treatment. The lack of nifH expression by gammaproteobacteria, in any of the DOM addition treatments applied, questions the contribution of non

Endochondral fracture healing with external fixation in the Sost knockout mouse results in earlier fibrocartilage callus removal and increased bone volume fraction and strength.

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Morse, A; Yu, N Y C; Peacock, L; Mikulec, K; Kramer, I; Kneissel, M; McDonald, M M; Little, D G

2015-02-01

Sclerostin deficiency, via genetic knockout or anti-Sclerostin antibody treatment, has been shown to cause increased bone volume, density and strength of calluses following endochondral bone healing. However, there is limited data on the effect of Sclerostin deficiency on the formative early stage of fibrocartilage (non-bony tissue) formation and removal. In this study we extensively investigate the early fibrocartilage callus. Closed tibial fractures were performed on Sost(-/-) mice and age-matched wild type (C57Bl/6J) controls and assessed at multiple early time points (7, 10 and 14days), as well as at 28days post-fracture after bony union. External fixation was utilized, avoiding internal pinning and minimizing differences in stability stiffness, a variable that has confounded previous research in this area. Normal endochondral ossification progressed in wild type and Sost(-/-) mice with equivalent volumes of fibrocartilage formed at early day 7 and day 10 time points, and bony union in both genotypes by day 28. There were no significant differences in rate of bony union; however there were significant increases in fibrocartilage removal from the Sost(-/-) fracture calluses at day 14 suggesting earlier progression of endochondral healing. Earlier bone formation was seen in Sost(-/-) calluses over wild type with greater bone volume at day 10 (221%, p<0.01). The resultant Sost(-/-) united bony calluses at day 28 had increased bone volume fraction compared to wild type calluses (24%, p<0.05), and the strength of the fractured Sost(-/-) tibiae was greater than that that of wild type fractured tibiae. In summary, bony union was not altered by Sclerostin deficiency in externally-fixed closed tibial fractures, but fibrocartilage removal was enhanced and the resultant united bony calluses had increased bone fraction and increased strength. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Existence of vigorous lineages of crop-wild hybrids in Lettuce under field conditions.

Science.gov (United States)

Hooftman, Danny A P; Hartman, Yorike; Oostermeijer, J Gerard B; Den Nijs, Hans J C M

2009-01-01

Plant to plant gene flow is a route of environmental exposure for GM plants specifically since crosses with wild relatives could lead to the formation of more vigorous hybrids, which could increase the rate of introgression and the environmental impact. Here, we test the first step in the process of potential transgene introgression: whether hybrid vigor can be inherited to the next generation, which could lead to fixation of altered, i.e., elevated, quantitative traits. The potential for a permanent elevated fitness was tested using individual autogamous progeny lineages of hybrids between the crop Lactuca sativa (Lettuce) and the wild species Lactuca serriola (Prickly Lettuce). We compared progeny from motherplants grown under either greenhouse or field conditions. The survival of young plants depended strongly on maternal environment. Furthermore, we observed that offspring reproductive fitness components were correlated with maternal fitness. Our study demonstrates that post-zygotic genotypic sorting at the young plants stage reduces the number of genotypes non-randomly, leading to inheritance of high levels of reproductive traits in the surviving hybrid lineages, compared to the pure wild relatives. Consequently, directional selection could lead to displacement of the pure wild relative and fixation of more vigorous genome segments originating from crops, stabilizing plant traits at elevated levels. Such information can be used to indentify segments which are less likely to introgress into wild relative populations as a target for transgene insertion. © ISBR, EDP Sciences, 2010.

[Analysis of tension-distraction state in the shin bones fractures in conditions of external fixation with application of apparatuses with different spatially oriented supports].

Science.gov (United States)

Hutsuliak, V I

2014-09-01

In Autodesk Inventor 11 program, using method of end-capping elements, a three- dimensional computeric modelling of biomechanical systems of two models was conducted: I - "tibia - Ilizarov's apparatus with concentric location of supports"; II - "tibia - Ilizarov's apparatus with excentric location of supports". The loading, which was applied towards distal fragment in 6 standard degrees of freedom, was modelled for studying of the fixation rigidity of tibial fragments in these systems. Determination of the loading value in various directions, in which the fragment have had shifted by 1 mm, have constituted the main task of the investigation. In a model II a rigidity of the fragments fixation, in comparison with such in a model I, is bigger by 631.43% - while applying a compression loading, by 8.35 - 31.75% - the transversal one and by 19.72% - the rotation loading. While choosing the method of transosteal osteosynthesis of the shin bones the advantage, have the apparatuses with excentric location of supports, what secures the enhanced rigidity of the fragments fixation in comparison with such in apparatuses with concentric location of supports. Although, even in excentric location of supports in the apparatus the fixation rigidity is insufficient for early full loading of the traumatized extremity while walking. It is necessary to elaborate such apparatus, the form of which may be adopted toanatomic configuration of segment.

Biomechanical optimization of different fixation modes for a proximal femoral L-osteotomy

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Chen Hsih-Hao

2009-09-01

Full Text Available Abstract Background Numerous proposed surgical techniques have had minimal success in managing greater trochanter overgrowth secondary to retarded growth of the femoral capital epiphysis. For reconstruction of residual hip deformities, a novel type of proximal femur L-osteotomy was performed with satisfactory results. Although the clinical outcome was good, the biomechanical characteristics of the femur after such an osteotomy have not been clearly elucidated. Therefore, this study presents a three dimensional finite element analysis designed to understand the mechanical characteristics of the femur after the L-osteotomy. Methods A patient with left hip dysplasia was recruited as the study model for L-osteotomy. The normal right hip was used as a reference for performing the corrective surgery. Four FEA models were constructed using different numbers of fixation screws but the same osteotomy lengths together with four FEA models with the same number of fixation screws but different osteotomy lengths. The von Mises stress distributions and femoral head displacements were analyzed and compared. Results The results revealed the following: 1. The fixation devices (plate and screws sustained most of the external loading, and the peak value of von Mises stress on the fixation screws decreased with an increasing number of screws. 2. Additional screws are more beneficial on the proximal segment than on the distal segment for improving the stability of the postoperative femur. 3. The extent of osteotomy should be limited because local stress might be concentrated in the femoral neck region with increasing length of the L-osteotomy. Conclusion Additional screw placement on the proximal segment improves stability in the postoperative femur. The cobra-type plate with additional screw holes in the proximal area might improve the effectiveness of L-osteotomies.

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.

Immaturity of Visual Fixations in Dyslexic Children.

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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.

Graft fixation in cruciate ligament reconstruction.

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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.

Avascular Necrosis of Acetabulum: The Hidden Culprit of Resistant Deep Wound Infection and Failed Fixation of Fracture Acetabulum - A Case Report.

Science.gov (United States)

K, Kandhari V; M, Desai M; S, Bava S; N, Wade R

2015-01-01

Chances of avascular necrosis of acetabulum are rare as it enjoys a rich blood supply. But cases of post - traumatic avascular necrosis of acetabulum following fracture of posterior column have been well documented. Importance of identifying and suspecting the avascular necrosis of acetabulum is essential in cases of failed fixation of fracture acetabulum, previously operated using extensile approach to acetabulum; either extended anterior ilio - femoral or tri - radiate approach. Such patients usually present with repeated deep bone infection or with early failure of fixation with aseptic loosening and migration of its components. We present a similar case. 40 years female presented with inadequately managed transverse fracture of left acetabulum done by anterior extended ilio-inguinal approach. The fixation failed. She presented 6 months later with painful hip. Cemented total hip replacement was performed with reconstruction of acetabulum by posterior column plating. Six months postoperatively patient presented with dislodgement of cup, pelvic discontinuity and sinus in the thigh. Two stage revision surgery was planned. First implant, removal; debridement and antibiotic spacer surgery was performed. At second stage of revision total hip replacement, patient had Paprosky grade IIIb defect in acetabulum. Spacer was removed through the posterior approach. Anterior approach was taken for anterior plating. Intra-operatively external iliac pulsations were found to be absent so procedure was abandoned after expert opinion. Postoperatively digital subtraction angiography demonstrated a chronic block in the external iliac artery and corona mortis was the only patent vascular channel providing vascular to the left lower limb. Thus, peripheral limb was stealing blood supply from the acetabulum to maintain perfusion. Patient was ultimately left with pelvic discontinuity, excision arthroplasty and pseudoarthrosis of the left hip. Avascular necrosis of acetabulum is a rare

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

Pectoralis Major Repair With Unicortical Button Fixation And Suture Tape.

Science.gov (United States)

Sanchez, Anthony; Ferrari, Marcio B; Frangiamore, Salvatore J; Sanchez, George; Kruckeberg, Bradley M; Provencher, Matthew T

2017-06-01

Although injuries of the pectoralis major muscle are generally uncommon, ruptures of the pectoralis major are occasionally seen in younger, more active patients who participate in weightlifting activities. These injuries usually occur during maximal contraction of the muscle, while in extension and external rotation. In the case of a rupture, operative treatment is advocated especially in young, active patients regardless of the chronicity of the injury. Various surgical techniques for reattachment of the avulsed tendon have been described, but bone tunnel and suture anchor repair techniques are most widely used. In this Technical Note, we present our preferred technique for acute pectoralis major rupture repair involving use of cortical buttons for tendon stump-to-bone fixation.

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

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

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...

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.

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.

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

Variable Nitrogen Fixation in Wild Populus.

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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.

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

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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.

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...

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.

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.

Early results of a simple distraction dynamic external fixator in management of comminuted intra-articular fractures of base of middle phalanx.

Science.gov (United States)

Mansha, Muhammad; Miranda, Sanjay

2013-12-01

Treatment for comminuted fracture dislocations of the proximal interphalangeal joint (pilon injuries) remains a challenge. We present our short term results of twelve pilon fracture dislocations treated by closed reduction and application of a distraction dynamic external fixator. The aim of the study was to assess the clinical outcomes and compare them to the original description by Hynes and Giddins. A cohort of 12 consecutive patients with pilon fracture of the proximal interphalangeal joint (comminuted fracture of the base of middle phalanx, longitudinally unstable with joint subluxation), were treated with this method over the study period. Data was collected by an independent observer at last follow-up appointment in the clinic. The outcome measures recorded were; level of residual pain, arc of motion, X-ray appearance, return to work and satisfaction with the procedure. The study group comprises of 7 male and 5 female patients at a mean age of 38.1 years (range 21-70 years). The average range of movement achieved was 13-87° at a mean follow-up of 16.4 weeks (Range 12-42 weeks). Early return to work, good pain relief and high level of patient satisfaction were achieved. No serious complication was noted during this period. We used the construct with slight modification of the original description and we feel this modification may help to reduce the pin site infection. We found the results reproducible and based on our experience we recommend this technique to treat these complex intra-articular fractures of base of middle phalanx.

Management of Late Onset Perthes: Evaluation of Distraction by External Fixator—5-Year Follow-Up

Directory of Open Access Journals (Sweden)

Ajai Singh

2014-01-01

Full Text Available Background. Hip distraction in Perthes’ disease unloads the joint, which negates the harmful effect of the stresses on the articular surfaces, which may promote the sound healing of the area of necrosis. We have examined the effect of arthrodiastasis on the preservation of the femoral head in older children with Perthes’ disease. Methods and Materials. Twelve children with age more than 8 years with Perthes’ disease of less than one year were treated with hip distraction by a hinged monolateral external fixator. Observation and Results. Mean duration of distraction was 13.9 days. These children were evaluated by clinicoradiological parameters for a mean period of 32.4 months. There was a significant improvement in the range of movements and mean epiphyseal index, but the change in the percentage of uncovered head femur was insignificant. There was significant improvement in Harris Hip score. Conclusions. Hip distraction by hinged monolateral external fixator seems to be a valid treatment option in cases with Perthes’ disease in the selected group of patients, where poor results are expected from conventional treatment.

Minimally invasive anterior pelvic internal fixation: An anatomic study comparing Pelvic Bridge to INFIX.

Science.gov (United States)

Reichel, Lee M; MacCormick, Lauren M; Dugarte, Anthony J; Rizkala, Amir R; Graves, Sara C; Cole, Peter A

2018-02-01

Anterior external fixation for pelvic ring fractures has shown to effectively improve stability and reduce mortality. However, these fixators can be associated with substantial morbidity such as pin tract infection, premature loss of fixation, and decreased quality of life in patients. Recently, two new methods of subcutaneous anterior pelvic internal fixation have been developed; the INFIX and the Pelvic Bridge. These methods have the purported advantages of lower wound complications, less surgical site pain, and improved quality of life. We sought to investigate the measured distances to critical anatomic structures, as well as the qualitative and topographic differences notable during implantation of both devices in the same cadaveric specimen. The Pelvic Bridge and INFIX were implanted in eleven fresh cadavers. Distances were then measured to: the superficial inguinal ring, round ligament, spermatic cord, lateral femoral cutaneous nerve (LFCN), femoral nerve, femoral artery, and femoral vein. Observations regarding implantation and topography were also recorded. The INFIX had greater measured distances from all structures except for the LFCN, in which its proximity placed this structure at risk. Neither device appears to put other critical structures at risk in the supine position. Significant implantation and topographic differences exist between the devices. The INFIX application lacked "safety margins" concerning the LFCN in 10/11 (90.9%) specimens, while Pelvic Bridge placement lacked "safety margins" with regard to the right superficial ring (1/11, 9%) and the right spermatic cord (1/11, 9%). Both the Pelvic Bridge and INFIX lie at safe distances from most critical pelvic structures in the supine position, though INFIX application places the LFCN at risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fixator-assisted medial tibial plateau elevation to treat severe Blount's disease: outcomes at maturity.

Science.gov (United States)

Fitoussi, F; Ilharreborde, B; Lefevre, Y; Souchet, P; Presedo, A; Mazda, K; Penneçot, G F

2011-04-01

Severe forms of Blount's disease may be associated with medial tibial plateau (MTP) depression. Management should then take account of joint congruence, laxity, limb axis, torsional abnomality, leg length discrepancy (LLD) and eventual recurrence history. Eight knees (six patients) were managed in a single step comprising MTP elevation osteotomy, lateral epiphysiodesis and proximal tibia osteotomy to correct varus and rotational deformity. Fixation was achieved using an Ilizarov external fixator. Mean age was 10.5 years. Mean hip-knee-ankle (HKA) angle was 151°; distal femoral varus, 94°; metaphyseal-diaphyseal angle (MDA), 27°; and angle of depression of the medial tibial plateau (ADMTP), 42°. Predicted residual proximal tibial growth was 2.6 cm. At a mean 48 months' follow-up, results were good in six cases, medium in one and poor (due to incomplete lateral epiphysiodesis) in one. Mean lateral tibial torsion was 9° and final LLD 11 mm. Weight-bearing was resumed at 2 months, and the fixator was removed at 5.5 months postoperatively. At end of follow-up, mean HKA angle was 179.6°, MDA 7.3° and ADMTP 5.4°. This technically demanding procedure gave satisfactory results in terms of axes and congruence; longer term assessment remains needed. Level IV. Retrospective study. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

New hybrid systems

International Nuclear Information System (INIS)

Bernardin, B.

2001-01-01

New hybrid systems are made up of a subcritical core, a spallation target and a proton accelerator. The neutrons that are produced in the target by the flux of protons are necessary to maintain the chain reaction of fission. Some parameters that are important for a classical nuclear reactor like doppler coefficient or delayed neutron fraction do not matter in a hybrid system. In a PWR-type reactor or in a fast reactor the concentration of actinides has a bad impact on these 2 parameters, so it is justified to study hybrid systems as actinide transmuters. The hybrid system, because of its external source of neutrons can put aside an important reactivity margin. This reactivity margin can be used to design safer nuclear reactors (particularly in some situations of reactivity accidents) or to irradiate fuel elements containing high concentrations of minor actinides that could not be allowed in a classical reactor. This article reviews various ways of integrating hybrid systems in a population of already existing nuclear reactors in order to manage quantities of plutonium, of minor actinides or of long-life fission products. (A.C.)

Hybrid rail gun electromagnetic accelerators

International Nuclear Information System (INIS)

Chen, K.W.; Hachen, H.; Lee, A.; Legh, G.; Lin, T.; Mattay, S.; Wipf, S.

1983-01-01

Theoretical and experimental investigations on hybrid rail accelerators are presented. It is shown that the side surface areas and in some cases sabots of the projectile can be used to provide substantial amount of additional thrust. Moreover, it is shown that in most cases examined, external magnetic fields can be conveniently incorporated in the accelerator designs to supplement the rail-induced fields. Total thrusts in excess of 10 MN for kilogram-sized projectiles can in principle be established with driving currents of the order of 1 MA. No obvious stress limitations are foreseen. The percentages of thrust from external magnetic fields are sufficiently high that the use of which should be encouraged. The increased flexibility in the projectile shapes available permits the use of the proposed hybrid electromagnetic launcher technology in a variety of new areas, such as thrust boosts in conventional chemical rockets and other similar applications. Furthermore, the additional thrust obtained from the use of side surface areas greatly increases the maximum permissable thrust otherwise limited by material strength considerations. Thrust analyses for projectiles in several hybrid rail accelerator designs are discussed. Some laboratory experimental observations are presented

External noise distinguishes attention mechanisms.

Science.gov (United States)

Lu, Z L; Dosher, B A

1998-05-01

We developed and tested a powerful method for identifying and characterizing the effect of attention on performance in visual tasks as due to signal enhancement, distractor exclusion, or internal noise suppression. Based on a noisy Perceptual Template Model (PTM) of a human observer, the method adds increasing amounts of external noise (white gaussian random noise) to the visual stimulus and observes the effect on performance of a perceptual task for attended and unattended stimuli. The three mechanisms of attention yield three "signature" patterns of performance. The general framework for characterizing the mechanisms of attention is used here to investigate the attentional mechanisms in a concurrent location-cued orientation discrimination task. Test stimuli--Gabor patches tilted slightly to the right or left--always appeared on both the left and the right of fixation, and varied independently. Observers were cued on each trial to attend to the left, the right, or evenly to both stimuli, and decide the direction of tilt of both test stimuli. For eight levels of added external noise and three attention conditions (attended, unattended, and equal), subjects' contrast threshold levels were determined. At low levels of external noise, attention affected threshold contrast: threshold contrasts for non-attended stimuli were systematically higher than for equal attention stimuli, which were, in turn, higher than for attended stimuli. Specifically, when the rms contrast of the external noise is below 10%, there is a consistent 17% elevation of contrast threshold from attended to unattended condition across all three subjects. For higher levels of external noise, attention conditions did not affect threshold contrast values at all. These strong results are characteristic of a signal enhancement, or equivalently, an internal additive noise reduction mechanism of attention.

Calculation of the power factor using the neutron diffusion hybrid equation

International Nuclear Information System (INIS)

Costa da Silva, Adilson; Carvalho da Silva, Fernando; Senra Martinez, Aquilino

2013-01-01

Highlights: ► A neutron diffusion hybrid equation with an external neutron source was used. ► Nodal expansion method to obtain the neutron flux was used. ► Nuclear power factors in each fuel element in the reactor core were calculated. ► The results obtained were very accurate. -- Abstract: In this paper, we used a neutron diffusion hybrid equation with an external neutron source to calculate nuclear power factors in each fuel element in the reactor core. We used the nodal expansion method to obtain the neutron flux for a given control rods bank position. The results were compared with results obtained for eigenvalue problem near criticality condition and fixed source problem during the start-up of the reactor, where external neutron sources are extremely important for the stabilization of external neutron detectors.

Maxwellian Eye Fixation during Natural Scene Perception

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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.

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

Hybrid Ceramic Matrix Fibrous Composites: an Overview

International Nuclear Information System (INIS)

Naslain, R

2011-01-01

Ceramic-Matrix Composites (CMCs) consist of a ceramic fiber architecture in a ceramic matrix, bonded together through a thin interphase. The present contribution is limited to non-oxide CMCs. Their constituents being oxidation-prone, they are protected by external coatings. We state here that CMCs display a hybrid feature, when at least one of their components is not homogeneous from a chemical or microstructural standpoint. Hybrid fiber architectures are used to tailor the mechanical or thermal CMC-properties whereas hybrid interphases, matrices and coatings to improve CMC resistance to aggressive environments.

Hybrid Ceramic Matrix Fibrous Composites: an Overview

Science.gov (United States)

Naslain, R.

2011-10-01

Ceramic-Matrix Composites (CMCs) consist of a ceramic fiber architecture in a ceramic matrix, bonded together through a thin interphase. The present contribution is limited to non-oxide CMCs. Their constituents being oxidation-prone, they are protected by external coatings. We state here that CMCs display a hybrid feature, when at least one of their components is not homogeneous from a chemical or microstructural standpoint. Hybrid fiber architectures are used to tailor the mechanical or thermal CMC-properties whereas hybrid interphases, matrices and coatings to improve CMC resistance to aggressive environments.

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....

High dark inorganic carbon fixation rates by specific microbial groups in the Atlantic off the Galician coast (NW Iberian margin).

Science.gov (United States)

Guerrero-Feijóo, Elisa; Sintes, Eva; Herndl, Gerhard J; Varela, Marta M

2018-02-01

Bulk dark dissolved inorganic carbon (DIC) fixation rates were determined and compared to microbial heterotrophic production in subsurface, meso- and bathypelagic Atlantic waters off the Galician coast (NW Iberian margin). DIC fixation rates were slightly higher than heterotrophic production throughout the water column, however, more prominently in the bathypelagic waters. Microautoradiography combined with catalyzed reporter deposition fluorescence in situ hybridization (MICRO-CARD-FISH) allowed us to identify several microbial groups involved in dark DIC uptake. The contribution of SAR406 (Marinimicrobia), SAR324 (Deltaproteobacteria) and Alteromonas (Gammaproteobacteria) to the dark DIC fixation was significantly higher than that of SAR202 (Chloroflexi) and Thaumarchaeota, in agreement with their contribution to microbial abundance. Q-PCR on the gene encoding for the ammonia monooxygenase subunit A (amoA) from the putatively high versus low ammonia concentration ecotypes revealed their depth-stratified distribution pattern. Taken together, our results indicate that chemoautotrophy is widespread among microbes in the dark ocean, particularly in bathypelagic waters. This chemolithoautotrophic biomass production in the dark ocean, depleted in bio-available organic matter, might play a substantial role in sustaining the dark ocean's food web. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

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.

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.

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.

Results of operative fixation of unstable ankle fractures in geriatric patients.

Science.gov (United States)

Pagliaro, A J; Michelson, J D; Mizel, M S

2001-05-01

It is widely accepted that operative fixation of unstable ankle fractures yields predictably good outcomes in the general population. The current literature, however reports less acceptable results in the geriatric population age 65 years and older. The current study analyzes the outcome of the surgical treatment of unstable ankle fractures in patients at least 65 years old. Twenty three patient over 65 years old were surgically treated after sustaining 21 (91%) closed and 2 (9%) open grade II unstable ankle fractures. Fractures were classified according to the Danis-Weber and Lauge-Hansen schemes. Fracture type was predominantly Weber B (21/23, 91%), or supination external rotation stage IV (21/23, 91%). Fracture union rate was 100%. There were three significant complications including a lateral wound dehiscence with delayed fibular union in an open fracture dislocation, and two below knee amputations, neither of which was directly related to the fracture treatment. There were three minor complications; one superficial wound infection and two cases of prolonged incision drainage, all of which resolved without further surgical intervention. Complications were associated with open fractures and preexisting systemic disease. These results indicate that open reduction and internal fixation of unstable ankle fractures in geriatric patients is an efficacious treatment regime that with results that are comparable to the general population.

In vitro mechanical evaluation of a novel pin-sleeve system for external fixation of distal limb fractures in horses: a proof of concept study.

Science.gov (United States)

Brianza, Stefano; Brighenti, Vittoria; Boure, Ludovic; Sprenger, Victor; Pearce, Simon; Schwieger, Karsten

2010-07-01

To evaluate the efficacy of a novel pin-sleeve cast (PSC) system for external fixation of distal limb fractures in horses and to compare it with the transfixation pin cast (TPC) system. Experimental. One bone substitute each was used for the TPC and PSC systems. The PSC was tested in 4 configurations characterized by different pin preloads. Specimens were loaded in axial compression in the elastic range. Variables compared statistically were: bone substitute axial displacement and axial strain measured above implants with strain gauges. Pin preload was correlated with the variables investigated. Load to failure and a fatigue tests supplemented the investigation. The PSC configuration with the highest pin preload showed a significantly lower axial displacement compared with the TPC. No significant differences were observed between all other PSC configurations and the TPC. All PSC systems had a significant decrease in recorded strain compared with the TPC system. Pin axial preload inversely correlated with axial displacement but had no effect on axial strain. In the failure test, the PSC encountered plastic deformation earlier than the TPC. In the fatigue test, the PSC ran >200,000 cycles. Preliminary in vitro tests showed that the PSC system significantly reduced peri-implant strain while concurrently having comparable axial displacement to the TPC system. The PSC system has the potential to reduce the risk of pin loosening in horses.

Examination of Skill Acquisition and Grader Bias in a Distal Radius Fracture Fixation Model.

Science.gov (United States)

Putnam, Matthew D; Adams, Julie E; Lender, Paul; Van Heest, Ann E; Shanedling, Janet R; Nuckley, David J; Bechtold, Joan E

2018-03-01

Primary: Assess the ability of faculty graders to predict the objectively measured strength of distal radius fracture fixation. Secondary: Compare resident skill variation and retention related to other knowable training data. Residents were allowed 60 minutes to stabilize a standardized distal radius fracture using an assigned fixed-angle volar plate. Faculty observed and subjectively graded the residents without providing real-time feedback. Objective biomechanical evaluation (construct strength and stiffness) was compared to subjective grades. Resident-specific characteristics (sex, PGY, and ACGME case log) were also used to compare the objective data. A simulated operating room in our laboratory. Post-graduate year 2, 3, 4, and 5 orthopedic residents. Primary: Faculty were not successful at predicting objectively measured fixation, and their subjective scoring suggests confirmation bias as PGY increased. Secondary: Resident year-in-training alone did not predict objective measures (p = 0.53), but was predictive of subjective scores (p external faculty unfamiliar with tested residents, might alter these results. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

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)

Incidence and risk factors for surgical site infection after open reduction and internal fixation of tibial plateau fracture: A systematic review and meta-analysis.

Science.gov (United States)

Shao, Jiashen; Chang, Hengrui; Zhu, Yanbin; Chen, Wei; Zheng, Zhanle; Zhang, Huixin; Zhang, Yingze

2017-05-01

This study aimed to quantitatively summarize the risk factors associated with surgical site infection after open reduction and internal fixation of tibial plateau fracture. Medline, Embase, CNKI, Wanfang database and Cochrane central database were searched for relevant original studies from database inception to October 2016. Eligible studies had to meet quality assessment criteria according to the Newcastle-Ottawa Scale, and had to evaluate the risk factors for surgical site infection after open reduction and internal fixation of tibial plateau fracture. Stata 11.0 software was used for this meta-analysis. Eight studies involving 2214 cases of tibial plateau fracture treated by open reduction and internal fixation and 219 cases of surgical site infection were included in this meta-analysis. The following parameters were identified as significant risk factors for surgical site infection after open reduction and internal fixation of tibial plateau fracture (p operative time (OR 2.15; 95% CI 1.53-3.02), tobacco use (OR 2.13; 95% CI 1.13-3.99), and external fixation (OR 2.07; 95% CI 1.05-4.09). Other factors, including male sex, were not identified as risk factors for surgical site infection. Patients with the abovementioned medical conditions are at risk of surgical site infection after open reduction and internal fixation of tibial plateau fracture. Surgeons should be cognizant of these risks and give relevant preoperative advice. Copyright © 2017. Published by Elsevier Ltd.

Biomechanical in vitro evaluation of three stable internal fixation techniques used in sagittal osteotomy of the mandibular ramus: a study in sheep mandibles

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Leandro Benetti de Olivera

2012-08-01

Full Text Available Among the osteotomies performed in orthognathic surgery, the sagittal osteotomy of the mandibular ramus (SOMR is the most common, allowing a great range of movements and stable internal fixation (SIF, therefore eliminating the need of maxillomandibular block in the postoperative period. OBJECTIVES: The purpose of this study was to evaluate the biomechanical resistance of three national systems used for SIF in SOMR in sheep mandibles. MATERIAL AND METHODS: The study was performed in 30 sheep hemi-mandibles randomly divided into 3 experimental groups, each containing 10 hemi-mandibles. The samples were measured to avoid discrepancies and then subjected to SOMR with 5-mm advancement. In group I, 2.0x12 mm screws were used for fixation, inserted in an inverted "L" pattern (inverted "L" group. In group II, fixation was performed with two 2.0x12 mm screws, positioned in a linear pattern and a 4-hole straight miniplate and four 2.0x6.0 mm monocortical screws (hybrid group. In group III, fixation was performed with two 4-hole straight miniplates and eight 2.0x6.0 mm monocortical screws (mini plate group. All materials used for SIF were supplied by Osteosin - SIN. The hemimandibles were subjected to vertical linear load test by Kratos K2000MP mechanical testing unit for loading registration and displacement. RESULTS: All groups showed similar resistance during mechanical test for loading and displacement, with no statistically significant differences between groups according to analysis of variance. CONCLUSION: These results indicate that the three techniques of fixation are equally effective for clinical fixation of SOMR.

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

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

Biomechanical testing of a hybrid locking plate fixation of equine sesamoid osteotomies.

Science.gov (United States)

Almeida da Silveira, E; Levasseur, A; Lacourt, M; Elce, Y; Petit, Y

2014-01-01

To compare the biomechanical properties of a hybrid locking compression plate (LCP) construct with the compression screw technique as a treatment for transverse mid-body proximal sesamoid bone fractures. Ten paired forelimbs from abattoir horses were used. The medial proximal sesamoid bone of each limb was osteotomized transversely and randomly assigned, to either repair with a two-hole 3.5 mm LCP or a 4.5 mm cortical screw placed in lag fashion. Each limb was tested biomechanically by axial loading in single cycle until failure. The point of failure was evaluated from the load-displacement curves. Then a gross evaluation and radiographs were performed to identify the mode of failure. The loads to failure of limbs repaired with the hybrid LCP construct (4968 N ± 2167) and the limbs repaired with the screw technique (3009 N ± 1091) were significantly different (p fracture of the apical fragment of the proximal sesamoid bone. The LCP technique has potential to achieve a better fracture stability and healing when applied to mid-body fractures of the proximal sesamoid bone. Further testing, particularly fatigue resistance is required to corroborate its potential as a treatment option for mid-body fractures of the proximal sesamoid bone.

External Benefit Evaluation of Renewable Energy Power in China for Sustainability

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Huiru Zhao

2015-04-01

Full Text Available China’s renewable energy power has developed rapidly in recent years. Evaluating the external benefits of renewable energy power can provide a reference for the Chinese government to set diverse development goals and to implement differentiated supporting policies for different renewable energy power types, which can promote their sustainable development. In this paper, a hybrid MCDM method was applied to evaluate the external benefits of China’s renewable energy power. Firstly, the impacts of renewable energy power accessing the power grid for multiple stakeholders in the electric power system were analyzed. Secondly, the external benefit evaluation index system for renewable energy power was built from the economic, social and environmental factors, based on the concept of sustainability. Then, the basic theory of the hybrid MCDM method employed in this paper was introduced in two parts: the superiority linguistic ratings and entropy weighting method for index weight determination and the fuzzy grey relation analysis for ranking alternatives. Finally, the external benefits of wind power, solar PV power and biomass power were evaluated. Taking a regional electric power system as an example, the results show that PV power has the greatest external benefit, followed by wind power and biomass power. Therefore, more policies supporting PV power should be put in place to promote the harmonious and sustainable development of the whole renewable energy power industry.

The importance of nodule CO2 fixation for the efficiency of symbiotic nitrogen fixation in pea at vegetative growth and during pod formation.

Science.gov (United States)

Fischinger, Stephanie Anastasia; Schulze, Joachim

2010-05-01

Nodule CO2 fixation is of pivotal importance for N2 fixation. The process provides malate for bacteroids and oxaloacetate for nitrogen assimilation. The hypothesis of the present paper was that grain legume nodules would adapt to higher plant N demand and more restricted carbon availability at pod formation through increased nodule CO2 fixation and a more efficient N2 fixation. Growth, N2 fixation, and nodule composition during vegetative growth and at pod formation were studied in pea plants (Pisum sativum L.). In parallel experiments, 15N2 and 13CO2 uptake, as well as nodule hydrogen and CO2 release, was measured. Plants at pod formation showed higher growth rates and N2 fixation per plant when compared with vegetative growth. The specific activity of active nodules was about 25% higher at pod formation. The higher nodule activity was accompanied by higher amino acid concentration in nodules and xylem sap with a higher share of asparagine. Nodule 13CO2 fixation was increased at pod formation, both per plant and per 15N2 fixed unit. However, malate concentration in nodules was only 40% of that during vegetative growth and succinate was no longer detectable. The data indicate that increased N2 fixation at pod formation is connected with strongly increased nodule CO2 fixation. While the sugar concentration in nodules at pod formation was not altered, the concentration of organic acids, namely malate and succinate, was significantly lower. It is concluded that strategies to improve the capability of nodules to fix CO2 and form organic acids might prolong intensive N2 fixation into the later stages of pod formation and pod filling in grain legumes.

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)

The effect of hubs and shortcuts on fixation time in evolutionary graphs

Science.gov (United States)

Askari, Marziyeh; Moradi Miraghaei, Zeinab; Aghababaei Samani, Keivan

2017-07-01

How can a new species (like a gene, an idea, or a strategy) take over the whole of a population? This process, which is called fixation, is considerably affected by the structure of the population. There are two key quantities to quantify the fixation process, namely fixation probability and fixation time. Fixation probability has been vastly studied in recent years, but fixation time has not been completely explored, yet. This is because the discovery of a relationship between fixation time and network structure is quite challenging. In this paper we investigate this relationship for a number of well-known complex networks. We show that the existence of a few high-degree nodes (hubs) in the network results in a longer fixation time, while the existence of a few short-cuts decreases the fixation time. Furthermore we investigate the effect of network parameters, such as connection probability, on fixation time. We show that by increasing the density of edges, fixation time decreases for all types of studied networks. Finally, we survey the effect of rewiring probability in a Watts-Strogatz network on fixation time.

Surgical site infection after open reduction and internal fixation of tibial plateau fractures.

Science.gov (United States)

Lin, Shishui; Mauffrey, Cyril; Hammerberg, E Mark; Stahel, Philip F; Hak, David J

2014-07-01

The aim of this study was to identify risk factors for surgical site infections and to quantify the contribution of independent risk factors to the probability of developing infection after definitive fixation of tibial plateau fractures in adult patients. A retrospective analysis was performed at a level I trauma center between January 2004 and December 2010. Data were collected from a review of the patient's electronic medical records. A total of 251 consecutive patients (256 cases) were divided into two groups, those with surgical site infections and those without surgical site infections. Preoperative and perioperative variables were compared between these groups, and risk factors were determined by univariate analyses and multivariate logistic regression. Variables analyzed included age, gender, smoking history, diabetes, presence of an open fracture, presence of compartment syndrome, Schatzker classification, polytrauma status, ICU stay, time from injury to surgery, use of temporary external fixation, surgical approach, surgical fixation, operative time, and use of a drain. The overall rate of surgical site infection after ORIF of tibial plateau fractures during the 7 years of this study was 7.8% (20 of 256). The most common causative pathogens was Staphylococcus aureus (n=15, 75%). Independent predictors of surgical site infection identified by multivariate analyses were open tibial plateau fracture (odds ratio=3.9; 95% CI=1.3-11.6; p=0.015) and operative time (odds ratio=2.7; 95% CI=1.6-4.4; psite infection. Both open fracture and operative time are independent risks factors for postoperative infection.

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.

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

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

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...

Frontier battery development for hybrid vehicles

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Lewis Heather

2012-04-01

Full Text Available Abstract Background Interest in hybrid-electric vehicles (HEVs has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this “hybrid premium” is the cost of the vehicles’ batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. Methods This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. Results The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Conclusions Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil.

Frontier battery development for hybrid vehicles.

Science.gov (United States)

Lewis, Heather; Park, Haram; Paolini, Maion

2012-04-23

Interest in hybrid-electric vehicles (HEVs) has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this "hybrid premium" is the cost of the vehicles' batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil.

Frontier battery development for hybrid vehicles

Science.gov (United States)

2012-01-01

Background Interest in hybrid-electric vehicles (HEVs) has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this “hybrid premium” is the cost of the vehicles’ batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. Methods This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. Results The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Conclusions Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil. PMID:22540987

Constrained state-feedback control of an externally excited synchronous machine

NARCIS (Netherlands)

Carpiuc, S.C.; Lazar, M.

2013-01-01

State-feedback control of externally excited synchronous machines employed in applications such as hybrid electric vehicles and full electric vehicles is a challenging problem. Indeed, these applications are characterized by fast dynamics that are subject to hard physical and control constraints.

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.

2.5-Gb/s hybridly-integrated tunable external cavity laser using a superluminescent diode and a polymer Bragg reflector.

Science.gov (United States)

Yoon, Ki-Hong; Oh, Su Hwan; Kim, Ki Soo; Kwon, O-Kyun; Oh, Dae Kon; Noh, Young-Ouk; Lee, Hyung-Jong

2010-03-15

We presented a hybridly-integrated tunable external cavity laser with 0.8 nm mode spacing 16 channels operating in the direct modulation of 2.5-Gbps for a low-cost source of a WDM-PON system. The tunable laser was fabricated by using a superluminescent diode (SLD) and a polymer Bragg reflector. The maximum output power and the power slope efficiency of the tunable laser were 10.3 mW and 0.132 mW/mA, respectively, at the SLD current of 100 mA and the temperature of 25 degrees C. The directly-modulated tunable laser successfully provided 2.5-Gbps transmissions through 20-km standard single mode fiber. The power penalty of the tunable laser was less than 0.8 dB for 16 channels after a 20-km transmission. The power penalty variation was less than 1.4 dB during the blue-shifted wavelength tuning.

Initial results of shoulder MRI in external rotation after primary shoulder dislocation and after immobilization in external rotation

International Nuclear Information System (INIS)

Pennekamp, W.; Nicolas, V.; Gekle, C.; Seybold, D.

2006-01-01

Purpose: A change in the strategy for treating primary anterior traumatic dislocation of the shoulder has occurred. To date, brief fixation of internal rotation via a Gilchrist bandage has been used. Depending on the patient's age, a redislocation is seen in up to 90% of cases. This is due to healing of the internally rotated labrum-ligament tear in an incorrect position. In the case of external rotation of the humerus, better repositioning of the labrum ligament complex is achieved. Using MRI of the shoulder in external rotation, the extent of the improved labrum-ligament adjustment can be documented, and the indication of immobilization of the shoulder in external rotation can be derived. The aim of this investigation is to describe the degree of position changing of the labrum-ligament tear in internal and external rotation. Materials and Methods: 10 patients (9 male, 1 female, mean age 30.4 years, range 15-43 years) with a primary anterior dislocation of the shoulder without hyper laxity of the contra lateral side and labrum-ligament lesion substantiated by MRI were investigated using a standard shoulder MRI protocol (PD-TSE axial fs, PD-TSE coronar fs, T2-TSE sagittal, T1-TSE coronar) by an axial PD-TSE sequence in internal and external rotation. The dislocation and separation of the anterior labrum-ligament complex were measured. The shoulders were immobilized in 10 external rotation for 3 weeks. After 6 weeks a shoulder MRI in internal rotation was performed. Results: In all patients there was a significantly better position of the labrum-ligament complex of the inferior rim in external rotation, because of the tension of the ventral capsule and the subscapular muscle. In the initial investigation, the separation of the labrum-ligament complex in internal rotation was 0.44±0.27 mm and the dislocation was 0.45±0.33 mm. In external rotation the separation was 0.01±0.19 mm and the dislocation was -0.08±0.28 mm. After 6 weeks of immobilization in 10 external

Stress and stability of plate-screw fixation and screw fixation in the treatment of Schatzker type IV medial tibial plateau fracture: a comparative finite element study.

Science.gov (United States)

Huang, Xiaowei; Zhi, Zhongzheng; Yu, Baoqing; Chen, Fancheng

2015-11-25

The purpose of this study is to compare the stress and stability of plate-screw fixation and screw fixation in the treatment of Schatzker type IV medial tibial plateau fracture. A three-dimensional (3D) finite element model of the medial tibial plateau fracture (Schatzker type IV fracture) was created. An axial force of 2500 N with a distribution of 60% to the medial compartment was applied to simulate the axial compressive load on an adult knee during single-limb stance. The equivalent von Mises stress, displacement of the model relative to the distal tibia, and displacement of the implants were used as the output measures. The mean stress value of the plate-screw fixation system was 18.78 MPa, which was significantly (P stress value of the triangular fragment in the plate-screw fixation system model was 42.04 MPa, which was higher than that in the screw fixation model (24.18 MPa). But the mean stress of the triangular fractured fragment in the screw fixation model was significantly higher in terms of equivalent von Mises stress (EVMS), x-axis, and z-axis (P < 0.001). This study demonstrated that the load transmission mechanism between plate-screw fixation system and screw fixation system was different and the stability provided by the plate-screw fixation system was superior to the screw fixation system.

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)

Acromioclavicular joint dislocation: a Dog Bone button fixation alone versus Dog Bone button fixation augmented with acromioclavicular repair-a finite element analysis study.

Science.gov (United States)

Sumanont, Sermsak; Nopamassiri, Supachoke; Boonrod, Artit; Apiwatanakul, Punyawat; Boonrod, Arunnit; Phornphutkul, Chanakarn

2018-03-20

Suspension suture button fixation was frequently used to treat acromioclavicular joint (ACJ) dislocation. However, there were many studies reporting about complications and residual horizontal instability after fixation. Our study compared the stability of ACJ after fixation between coracoclavicular (CC) fixation alone and CC fixation combined with ACJ repair by using finite element analysis (FEA). A finite element model was created by using CT images from the normal shoulder. The model 1 was CC fixation with suture button alone, and the model 2 was CC fixation with suture button combined with ACJ repair. Three different forces (50, 100, 200 N) applied to the model in three planes; inferior, anterior and posterior direction load to the acromion. The von Mises stress of the implants and deformation at ACJs was recorded. The ACJ repair in the model 2 could reduce the peak stress on the implant after applying the loading forces to the acromion which the ACJ repair could reduce the peak stress of the FiberWire at suture button about 90% when compared to model 1. And, the ACJ repair could reduce the deformation of the ACJ after applying the loading forces to the acromion in both vertical and horizontal planes. This FEA supports that the high-grade injuries of the ACJ should be treated with CC fixation combined with ACJ repair because this technique provides excellent stability in both vertical and horizontal planes and reduces stress to the suture button.

"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.

Hybrid computing using a neural network with dynamic external memory.

Science.gov (United States)

Graves, Alex; Wayne, Greg; Reynolds, Malcolm; Harley, Tim; Danihelka, Ivo; Grabska-Barwińska, Agnieszka; Colmenarejo, Sergio Gómez; Grefenstette, Edward; Ramalho, Tiago; Agapiou, John; Badia, Adrià Puigdomènech; Hermann, Karl Moritz; Zwols, Yori; Ostrovski, Georg; Cain, Adam; King, Helen; Summerfield, Christopher; Blunsom, Phil; Kavukcuoglu, Koray; Hassabis, Demis

2016-10-27

Artificial neural networks are remarkably adept at sensory processing, sequence learning and reinforcement learning, but are limited in their ability to represent variables and data structures and to store data over long timescales, owing to the lack of an external memory. Here we introduce a machine learning model called a differentiable neural computer (DNC), which consists of a neural network that can read from and write to an external memory matrix, analogous to the random-access memory in a conventional computer. Like a conventional computer, it can use its memory to represent and manipulate complex data structures, but, like a neural network, it can learn to do so from data. When trained with supervised learning, we demonstrate that a DNC can successfully answer synthetic questions designed to emulate reasoning and inference problems in natural language. We show that it can learn tasks such as finding the shortest path between specified points and inferring the missing links in randomly generated graphs, and then generalize these tasks to specific graphs such as transport networks and family trees. When trained with reinforcement learning, a DNC can complete a moving blocks puzzle in which changing goals are specified by sequences of symbols. Taken together, our results demonstrate that DNCs have the capacity to solve complex, structured tasks that are inaccessible to neural networks without external read-write memory.

Comparative study of thyroid fixation of different iodine compounds; Etude comparative de la fixation thyroidienne de differents composes iodes

Energy Technology Data Exchange (ETDEWEB)

Rinaldi, R; Coeur, A; Raynfeld, Ch [Commissariat a l' Energie Atomique, Grenoble (France).Centre d' Etudes Nucleaires

1961-07-01

The aim of this work is to study the thyroid fixation of various iodine compounds in mineral or organic form. The animals (rats) are given therapeutic doses of the derivative orally with the object of saturating the thyroid, and then receive a determined dose of radio-iodine 131 by intra-peritoneal injection; any fixation of this latter is then measured under anaesthetic by means of a scintillation counter. Whatever form of iodine derivative was used whether in ionic (potassium iodide type) or organic form (iodo-tannic syrup) or in the form of elementary iodine (iodinated water), thyroid saturation was always obtained, as shown by practically zero fixation of the 4 {mu}curies of iodine 131 administered by intra-peritoneal injection. (author) [French] Notre travail a pour but l'etude de la fixation thyroidienne de differents composes iodes sous forme minerale ou organique. Les animaux (rats), apres absorption orale de doses therapeutiques de derives destines a saturer leur thyroide recoivent par voie intra-peritoneale une dose determinee de radio-iode {sup 131}I, la fixation eventuelle de ce dernier est ensuite mesuree sous anesthesie en utilisant un compteur a scintillation. Quelle que soit la forme utilisee, c'est-a-dire derive iode sous forme ionique (type iodure de potassium) ou sous forme organique (sirop iodotanique) ou encore sous forme d'iode metalloidique (eau iodee), nous avons obtenu chaque fois une saturation thyroidienne mise en evidence par une fixation pratiquement nulle des 4 {mu}curies de l'iode 131 injectes par voie intraperitoneale. (auteur)

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

Directory of Open Access Journals (Sweden)

MY Loqman

2010-05-01

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

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...

External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

Energy Technology Data Exchange (ETDEWEB)

Abo-Elmagd, M [National Institute for Standard, Radiation Measurements Department, P.O. Box 136 Giza code no. 12211 (Egypt); Metwally, S M [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); Elmongy, S A [Atomic Energy Authority, Nuclear Safety, Cairo (Egypt); Salama, E [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); El-Fiki, S A [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt)

2006-02-15

Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43{mu}Sv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively.

External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

International Nuclear Information System (INIS)

Abo-Elmagd, M.; Metwally, S.M.; Elmongy, S.A.; Salama, E.; El-Fiki, S.A.

2006-01-01

Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43μSv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively

[TREATMENT OF PRONATION EXTERNAL ROTATION ANKLE FRACTURE COMBINED WITH SEPARATION OF DISTAL TIBIOFIBULAR SYNDESMOSIS].

Science.gov (United States)

Wu, Benwen; Ding, Zhenqi; Huang, Guofeng; Liu, Guojun; Cai, Zhemin; Ding, Luobin; Li, Xiang

2016-09-08

To evaluate the difference between using and not using syndesmotic screw to treat pronation external rotation (PER) ankle fracture combined with separation of distal tibiofibular syndesmosis. Between April 2011 and October 2014, 46 cases of PER ankle fracture combined with separation of distal tibiofibular syndesmosis were treated, and syndesmotic screw was used in 24 cases (fixation group) and syndesmotic screw was not used in 22 cases (non-fixation group). There was no significant difference in gender, age, weight, cause of injury, side, injury to operation time, and fracture type between 2 groups ( P >0.05). The time for full weight-bearing, fracture healing time, and complications were recorded after operation. Anteroposterior and lateral X-ray films were taken to measure the tibiofibular overlap (TBOL) and tibiofibular clear space (TBCS). Baird-Jackson score was used to evaluate functional recovery of the ankle. All incision healed by first intention without complications. The cases were followed up 13-18 months (mean, 15.2 months) in 2 groups. The time for full weight-bearing was 8-12 weeks (median, 11 weeks) in fixation group, which was significantly later than that in non-fixation group (range, 6-10 weeks; median, 8 weeks) ( Z =-5.049, P =0.000). X-ray examination showed reduction of separation of distal tibiofibular syndesmosis. All fractures healed. The fracture healing time was (13.83±1.37) weeks in fixation group, and was (13.91±1.31) weeks in non-fixation group, showing no significant difference ( t =-0.191, P =0.945). No separation of distal tibiofibular syndesmosis, delayed union, nonunion, loosening, or breakage of fixation devices was observed in 2 groups. There was no significant difference in TBOL, TBCS, Baird-Jackson score and the excellent and good rate between 2 groups ( P >0.05). If the medial, lateral, and posterior structures of the ankle could be repaired according to injury, no significant influence on functional outcome of ankle or

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.

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.

An Amorphous Noble-Metal-Free Electrocatalyst that Enables Nitrogen Fixation under Ambient Conditions.

Science.gov (United States)

Lv, Chade; Yan, Chunshuang; Chen, Gang; Ding, Yu; Sun, Jingxue; Zhou, Yansong; Yu, Guihua

2018-02-23

N 2 fixation by the electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions is regarded as a potential approach to achieve NH 3 production, which still heavily relies on the Haber-Bosch process at the cost of huge energy and massive production of CO 2 . A noble-metal-free Bi 4 V 2 O 11 /CeO 2 hybrid with an amorphous phase (BVC-A) is used as the cathode for electrocatalytic NRR. The amorphous Bi 4 V 2 O 11 contains significant defects, which play a role as active sites. The CeO 2 not only serves as a trigger to induce the amorphous structure, but also establishes band alignment with Bi 4 V 2 O 11 for rapid interfacial charge transfer. Remarkably, BVC-A shows outstanding electrocatalytic NRR performance with high average yield (NH 3 : 23.21 μg h -1  mg -1 cat. , Faradaic efficiency: 10.16 %) under ambient conditions, which is superior to the Bi 4 V 2 O 11 /CeO 2 hybrid with crystalline phase (BVC-C) counterpart. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Correlations and fixation of some elements in tree rings

International Nuclear Information System (INIS)

Goldberg, E.L.; Zolotarev, K.B.; Maksimovskaya, V.V.; Kondratyev, V.I.; Ovchinnikov, D.V.; Naurzbaev, M.M.

2007-01-01

High-resolution scanning with Synchrotron Radiation X-ray Fluorescence Analysis (SRXFA) was applied to investigate element distributions in tree rings. Two cores of Siberia Larch have been investigated with resolution 100-200 mkm. Two groups of elements in tree rings with different trends have been found. The members of the first group are Br, Zn, Cl, whose trends correlate with each other. Moreover, trends of Br, Zn, Cl in tree rings are similar to the trend of atmosphere precipitation in the region investigated. Other group of elements are represented by K, Ca, Sr, Mn, Fe, but their trends differ sufficiently from trend of elements of the first group. Extended fixation of elements in tree rings is observed for elements of the first group over the whole interval investigated (150 years). In contrast, elements of the second group mainly accumulate in external part of tree stem

Fixator-Assisted Lengthening and Deformity Correction Over an Intramedullary Nail in a Patient with Achondroplasia

Directory of Open Access Journals (Sweden)

Erdal Uzun

2016-05-01

Full Text Available Achondroplasia is the most frequently encountered form of nonlethal skeletal dysplasia and a type of rhizomelic dwarfism. It results in considerable physical and psychologic handicaps owing to the disproportionate stature of the body and difficulty in performing routine activities of daily living. They also have major musculoskeletal problems including symptomatic malalignment of the lower limbs. Limb lengthening has been used in patients with achondroplasia by different techniques (Intramedullar nailing, monolateral or circular external fixator. We report our treatment of a patient 17 years of age with achondroplasia for bilateral lower limb length discrepancy and bilateral tibial varus deformity.

Feasibility of purely endoscopic intramedullary fixation of mandibular condyle fractures.

Science.gov (United States)

Frake, Paul C; Goodman, Joseph F; Joshi, Arjun S

2015-01-01

The investigators of this study hypothesized that fractures of the mandibular condyle can be repaired using short-segment intramedullary implants and purely endoscopic surgical technique, using a basic science, human cadaver model in an academic center. Endoscopic instrumentation was used through a transoral mucosal incision to place intramedullary implants of 2 cm in length into osteotomized mandibular condyles. The surgical maneuvers that required to insert these implants, including condyle positioning, reaming, implant insertion, and seating of the mandibular ramus, are described herein. Primary outcome was considered as successful completion of the procedure. Ten cadaveric mandibular condyles were successfully repaired with rigid intramedullary internal fixation without the use of external incisions. Both insertion of a peg-type implant and screwing a threaded implant into the condylar head were possible. The inferior portion of the implant remained exposed, and the ramus of the mandible was manipulated into position on the implant using retraction at the sigmoid notch. The results of this study suggest that purely endoscopic repair of fractures of the mandibular condyle is possible by using short-segment intramedullary titanium implants and a transoral endoscopic approach without the need for facial incisions or punctures. The biomechanical advantages of these intramedullary implants, including improved strength and resistance to mechanical failure compared with miniplates, have been recently established. The combination of improved implant design and purely endoscopic technique may allow for improved fixation and reduced surgical- and implant-related morbidity in the treatment of condylar fractures.

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

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.

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.

Closed reduction with CT-guided screw fixation for unstable sacroiliac joint fracture-dislocation

Energy Technology Data Exchange (ETDEWEB)

Baskin, Kevin M.; Cahill, Ann Marie; Kaye, Robin D. [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Born, Christopher T. [Temple University Hospital/Temple Children' s Hospital, Temple Sports Medicine, Marlton, NJ (United States); Grudziak, Jan S. [Children' s Hospital of Pittsburgh, Department of Orthopedic Surgery, Pittsburgh, PA (United States); Towbin, Richard B.

2004-12-01

Unstable posterior pelvic ring fractures and dislocations are uncommon but potentially life-threatening injuries in children. Early definitive management reduces risk of immediate complications as well as chronic pain and gait dysfunction. Conventional operative therapy carries substantial risk of extensive blood loss and iatrogenic neurological and vascular injury. Minimally invasive image-guided intervention may further reduce immediate risk and improve long-term outcome. To describe CT-guided closed reduction and internal fixation (CRIF) and review outcomes of unstable fracture-dislocation of the sacroiliac (SI) joint in children. Between 2000 and 2003, three children (two girls, one boy) age 8-14 years were referred to interventional radiology for treatment of unstable SI joint fracture-dislocation not adequately treated with anterior external fixation alone. The three affected SI joints (two left, one right) were treated in a combined approach by pediatric interventional radiologists and orthopedic surgeons, using a percutaneous approach under CT guidance. Over a threaded guiding pin, 7.3 mm cannulated screws were used to achieve stable reduction of the affected SI joints. One screw was removed after slight (2 mm) migration. No neurovascular or other complications occurred. All patients had satisfactory healing with near-anatomic reduction, although recovery of the youngest was delayed by associated spinal injury. Compared to open surgical alternatives, CRIF under CT guidance reduces operating time, decreases blood loss, and allows early definitive fixation and immediate non-weight-bearing mobilization with a low rate of complication for unstable posterior pelvic ring fractures. In addition, CT-guided placement of the guide pin may allow safer screw positioning and may minimize the total number of screws needed to achieve pelvic stability. (orig.)

Closed reduction with CT-guided screw fixation for unstable sacroiliac joint fracture-dislocation

International Nuclear Information System (INIS)

Baskin, Kevin M.; Cahill, Ann Marie; Kaye, Robin D.; Born, Christopher T.; Grudziak, Jan S.; Towbin, Richard B.

2004-01-01

Unstable posterior pelvic ring fractures and dislocations are uncommon but potentially life-threatening injuries in children. Early definitive management reduces risk of immediate complications as well as chronic pain and gait dysfunction. Conventional operative therapy carries substantial risk of extensive blood loss and iatrogenic neurological and vascular injury. Minimally invasive image-guided intervention may further reduce immediate risk and improve long-term outcome. To describe CT-guided closed reduction and internal fixation (CRIF) and review outcomes of unstable fracture-dislocation of the sacroiliac (SI) joint in children. Between 2000 and 2003, three children (two girls, one boy) age 8-14 years were referred to interventional radiology for treatment of unstable SI joint fracture-dislocation not adequately treated with anterior external fixation alone. The three affected SI joints (two left, one right) were treated in a combined approach by pediatric interventional radiologists and orthopedic surgeons, using a percutaneous approach under CT guidance. Over a threaded guiding pin, 7.3 mm cannulated screws were used to achieve stable reduction of the affected SI joints. One screw was removed after slight (2 mm) migration. No neurovascular or other complications occurred. All patients had satisfactory healing with near-anatomic reduction, although recovery of the youngest was delayed by associated spinal injury. Compared to open surgical alternatives, CRIF under CT guidance reduces operating time, decreases blood loss, and allows early definitive fixation and immediate non-weight-bearing mobilization with a low rate of complication for unstable posterior pelvic ring fractures. In addition, CT-guided placement of the guide pin may allow safer screw positioning and may minimize the total number of screws needed to achieve pelvic stability. (orig.)

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

Changes in biomolecular profile in a single nucleolus during cell fixation.

Science.gov (United States)

Kuzmin, Andrey N; Pliss, Artem; Prasad, Paras N

2014-11-04

Fixation of biological sample is an essential technique applied in order to "freeze" in time the intracellular molecular content. However, fixation induces changes of the cellular molecular structure, which mask physiological distribution of biomolecules and bias interpretation of results. Accurate, sensitive, and comprehensive characterization of changes in biomolecular composition, occurring during fixation, is crucial for proper analysis of experimental data. Here we apply biomolecular component analysis for Raman spectra measured in the same nucleoli of HeLa cells before and after fixation by either formaldehyde solution or by chilled ethanol. It is found that fixation in formaldehyde does not strongly affect the Raman spectra of nucleolar biomolecular components, but may significantly decrease the nucleolar RNA concentration. At the same time, ethanol fixation leads to a proportional increase (up to 40%) in concentrations of nucleolar proteins and RNA, most likely due to cell shrinkage occurring in the presence of coagulant fixative. Ethanol fixation also triggers changes in composition of nucleolar proteome, as indicated by an overall reduction of the α-helical structure of proteins and increase in the concentration of proteins containing the β-sheet conformation. We conclude that cross-linking fixation is a more appropriate protocol for mapping of proteins in situ. At the same time, ethanol fixation is preferential for studies of RNA-containing macromolecules. We supplemented our quantitative Raman spectroscopic measurements with mapping of the protein and lipid macromolecular groups in live and fixed cells using coherent anti-Stokes Raman scattering nonlinear optical imaging.

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.

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

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.

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

A device for external γ-irradiation of experimental animals

International Nuclear Information System (INIS)

Ivanitskaya, N.F.; Talakin, Yu.N.; Lekakh, V.A.

1992-01-01

A device was developed for external gamma-irradiation of experimental animals including a radiation source, a device for fixation of the total animal or a segment of its body in the focus of irradiation, and a shilding screen. To widen the sphere of this device application by making possible a simultaneous radiation exposure of a group of animals under various radiation schedules, the device involves two discs with a common axis. The lower disc is provided with an electric drive and containers with animals are placed on it, and the upper disc is for the shielding screen. The device is supplied with an operation block

Treatment of displaced talar neck fractures using delayed procedures of plate fixation through dual approaches.

Science.gov (United States)

Xue, Youdi; Zhang, Hui; Pei, Fuxing; Tu, Chongqi; Song, Yueming; Fang, Yue; Liu, Lei

2014-01-01

Treatment of talar neck fractures is challenging. Various surgical approaches and fixation methods have been documented. Clinical outcomes are often dissatisfying due to inadequate reduction and fixation with high rates of complications. Obtaining satisfactory clinical outcomes with minimum complications remains a hard task for orthopaedic surgeons. In the period from May 2007 to September 2010, a total of 31 cases with closed displaced talar neck fractures were treated surgically in our department. Injuries were classified according to the Hawkins classification modified by Canale and Kelly. Under general anaesthesia with sufficient muscle relaxation, urgent closed reduction was initiated once the patients were admitted; if the procedure failed, open reduction and provisional stabilisation with Kirschner wires through an anteromedial approach with tibiometatarsal external fixation were performed. When the soft tissue had recovered, definitive fixation was performed with plate and screws through dual approaches. The final follow-up examination included radiological analysis, clinical evaluation and functional outcomes which were carried out according to the Ankle-Hindfoot Scale of the American Orthopaedic Foot and Ankle Society (AOFAS), patient satisfaction and SF-36. Twenty-eight patients were followed up for an average of 25 months (range 18-50 months) after the injury. Only two patients had soft tissue complications, and recovery was satisfactory with conservative treatment. All of the fractures healed anatomically without malunion and nonunion, and the average union time was 14 weeks (range 12-24 weeks). Post-traumatic arthritis developed in ten cases, while six patients suffered from avascular necrosis of the talus. Secondary procedures included three cases of subtalar arthrodesis, one case of ankle arthrodesis and one case of total ankle replacement. The mean AOFAS hindfoot score was 78 (range 65-91). According to the SF-36, the average score of the

Disturbance observer-based adaptive sliding mode hybrid projective ...

Indian Academy of Sciences (India)

Ayub Khan

2018-04-21

Apr 21, 2018 ... systems, the effect of external disturbances, energy fluc- tuation and other such ...... When we apply the above proposed strategy to achieve hybrid projective ..... ory and intelligent control (Springer, 2016) pp. 681–. 697.

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)

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.

Study of lower hybrid current drive for the demonstration reactor

Energy Technology Data Exchange (ETDEWEB)

Molavi-Choobini, Ali Asghar [Dept. of Physics, Faculty of Engineering, Islamic Azad University, Shahr-e-kord Branch, Shahr-e-kord (Iran, Islamic Republic of); Naghidokht, Ahmed [Dept. of Physics, Urmia University, Urmia (Iran, Islamic Republic of); Karami, Zahra [Dept. of Engineering, Islamic Azad University, Zanjan Branch, Zanjan (Iran, Islamic Republic of)

2016-06-15

Steady-state operation of a fusion power plant requires external current drive to minimize the power requirements, and a high fraction of bootstrap current is required. One of the external sources for current drive is lower hybrid current drive, which has been widely applied in many tokamaks. Here, using lower hybrid simulation code, we calculate electron distribution function, electron currents and phase velocity changes for two options of demonstration reactor at the launched lower hybrid wave frequency 5 GHz. Two plasma scenarios pertaining to two different demonstration reactor options, known as pulsed (Option 1) and steady-state (Option 2) models, have been analyzed. We perceive that electron currents have major peaks near the edge of plasma for both options but with higher efficiency for Option 1, although we have access to wider, more peripheral regions for Option 2. Regarding the electron distribution function, major perturbations are at positive velocities for both options for flux surface 16 and at negative velocities for both options for flux surface 64.

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.

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.

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

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.

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…

Environmental and biogeochemical controls on N2 fixation in ombrotrophic peatlands

Science.gov (United States)

Zivkovic, T.; Moore, T. R.

2017-12-01

Northern peatlands have low atmospheric nitrogen (N) inputs and acquire N mostly via biological, microbially-driven N2-fixation. Little is known about rates and controls on N2-fixation in ombrotrophic bogs. We conducted two studies to test environmental and biogeochemical controls on N2-fixation. First, we used acetylene reduction assay (ARA) calibrated with 15N2 tracer to measure N2-fixation rates in three species of Sphagnum mosses along a hydrological gradient (beaver pond, hollow and hummock in bog margin and in bog) at Mer Bleue bog from June-October 2013 and May - November 2014. We tested the following controls: moisture availability, temperature, and PAR. The largest ARA rates throughout both seasons occurred in the pond in floating Sphagnum cuspidatum mats (50.3 ± 12.9 μmol m-2 d-1 Mean ± SE), which were up to 2.5 times larger than the rates found in the driest hummock site. There was a significant seasonal peak in both years in July and early August that coincided with the peak of the air temperature. In fact, 45% of the variance of N2 fixation rates over the two field seasons was explained by rain events, water table fluctuations and the surface peat temperature (multiple regression analysis, n = 539). Our results highlight the potential impact of climate change, namely negative effects due to potential droughts and positive effect of warming, on N2 fixation patterns in ombrotrophic peatlands. Secondly, we tested stoichiometric controls (Sphagnum tissue N and phosphorous (P) ratio) of N2-fixation. In a controlled environment, we selected eight study sites along a latitudinal gradient from temperate, boreal to subarctic zone in eastern Canada. We found that decreasing N:P ratio corresponded to increasing N2-fixation. N:P explained 65% of the variance in N2-fixation in hollows but only 20% in hummocks. Changes in neither N or P concentration alone explained the increase in N2-fixation better than N:P ratio. We interpret that the difference between

Uso de fijador externo en la inestabilidad de la pared torácica anterior (volet esternal: Presentación de un caso Use of the external fixative in the instability of the anterior thoraxic wall (sternal volet: A case report

Directory of Open Access Journals (Sweden)

Orestes N Mederos Curbelo

2005-03-01

Full Text Available Se presenta un paciente con inestabilidad de la pared torácica anterior y esternón tratado previamente con un dispositivo creado por los autores en 1995 para el volet costal. Las costillas artificiales externas del dispositivo, diseñado para el cerclaje subperióstico, actúan como elemento de fijación y han conseguido resultados satisfactorios. Se presenta un paciente, que producto de un accidente automovilístico, sufre lesiones en cráneo, tórax, abdomen y extremidades, entre las que resaltan contusión cerebral, lesión hepática, fractura de fémur e inestabilidad de la pared torácica anterior. Esta última requirió de prioridad extrema, pues habría llevado rápidamente al paciente a la insuficiencia respiratoria de no ser solucionado el problema. Se realizó la estabilización externa mediante un equipo que se utiliza en nuestro hospital, reutilizable y aplicable en cualquier inestabilidad torácica independientemente de la localización de esta. El fijador se confecciona con láminas de duraluminio maleables que permiten su adaptabilidad e introduce una forma de tratamiento en las lesiones torácicas bilaterales con inestabilidad esternal, situación compleja en la que puede resultar un instrumento valioso de tratamientoA patient with instability of the anterior thoracic wall and sternum previously treated with a device created by the authors in 1995 for the costal volet, is presented. The artificial external ribs of the device designed for subperiosteous cerclage act as a fixation element with satisfactory results. The case of a patient that due to a car accident suffers from lesions in the cranium, thorax, abdomen and limbs, among which cerebral contusion, liver lesion, femur fracture and instability of the anterior thoracic wall stand out, is reported. Maximum priority was given to the instability of the anterior thoracic wall, since it could have rapidly led to respiratory failure if the problem would have not been solved. The

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...

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.

Comparative Transcriptional Profiling of Three Super-Hybrid Rice Combinations

Directory of Open Access Journals (Sweden)

Yonggang Peng

2014-03-01

Full Text Available Utilization of heterosis has significantly increased rice yields. However, its mechanism remains unclear. In this study, comparative transcriptional profiles of three super-hybrid rice combinations, LY2163, LY2186 and LYP9, at the flowering and filling stages, were created using rice whole-genome oligonucleotide microarray. The LY2163, LY2186 and LYP9 hybrids yielded 1193, 1630 and 1046 differentially expressed genes (DGs, accounting for 3.2%, 4.4% and 2.8% of the total number of genes (36,926, respectively, after using the z-test (p < 0.01. Functional category analysis showed that the DGs in each hybrid combination were mainly classified into the carbohydrate metabolism and energy metabolism categories. Further analysis of the metabolic pathways showed that DGs were significantly enriched in the carbon fixation pathway (p < 0.01 for all three combinations. Over 80% of the DGs were located in rice quantitative trait loci (QTLs of the Gramene database, of which more than 90% were located in the yield related QTLs in all three combinations, which suggested that there was a correlation between DGs and rice heterosis. Pathway Studio analysis showed the presence of DGs in the circadian regulatory network of all three hybrid combinations, which suggested that the circadian clock had a role in rice heterosis. Our results provide information that can help to elucidate the molecular mechanism underlying rice heterosis.

Nitrogen fixation by free-living organisms in rice soils. Studies with 15N

International Nuclear Information System (INIS)

Rao, V.R.; Charyulu, P.B.B.N.; Nayak, D.N.; Ramakrishna, C.

1979-01-01

Heterotrophic nitrogen fixation as influenced by water regime, organic matter, combined nitrogen and pesticides was investigated in several Indian rice soils by means of the 15 N 2 tracer technique. Soil submergence accelerated nitrogen fixation. Addition of cellulose to both non-flooded and flooded soils enhanced nitrogen fixation. Under submerged conditions, addition of sucrose, glucose and malate in that order stimulated nitrogen fixation in alluvial soil, while only sucrose enhanced nitrogen fixation in laterite soil. Nitrogen fixation in flooded alluvial and laterite soils decreased with increasing concentration of combined nitrogen. Nitrogen fixation was appreciable in acid sulphate and saline soils under both flooded and non-flooded conditions, despite high salinity and acidity. Application of certain pesticides at rates equivalent to recommended field level greatly influenced nitrogen fixation in flooded rice soils. Additions of benomyl (carbamate fungicide) and carbofuran (methyl carbamate insecticide) to alluvial and laterite soils resulted in significant stimulation of nitrogen fixation. Gamma-BHC stimulated nitrogen fixation only in alluvial soil, with considerable inhibition in a laterite soil. Nitrogen fixation by Azospirillum lipoferum was investigated by 15 N 2 . Large variations in 15 N 2 incorporation by A. lipoferum isolated from the roots of several rice cultivars was observed. Specific lines of rice harbouring A. lipoferum with high nitrogenase activity might be selected. Nitrogen fixed by heterotrophic organisms in a complex system such as soil could not be evaluated precisely. Indigenous nitrogen fixation in a flooded soil would be in the range of 5-10 kg N/ha, increasable 3 to 4-fold by appropriate fertilizers and cultural practices

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

Directory of Open Access Journals (Sweden)

Michael Bemelman

2016-02-01

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

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

Science.gov (United States)

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

2016-01-01

More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950’s, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has become available suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation. PMID:26889439

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).

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.

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.

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

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

The effect of tissue decalcification on mRNA retention within bone for in-situ hybridization studies.

Science.gov (United States)

Walsh, L; Freemont, A J; Hoyland, J A

1993-06-01

Tissue decalcification is a routine part of the preparation of bone tissue for histological studies. Although in-situ hybridization has been employed to localize mRNA of collagenous and non-collagenous bone related proteins in skeletal tissue, little is known regarding the effects of decalcifying agents on mRNA retention within tissue. In this study in-situ hybridization using an oligonucleotide probe (i.e. a poly d(T) probe) to detect total messenger RNA has been employed to investigate the effects of the decalcifying agents nitric acid, formic acid and EDTA on mRNA retention compared to undeacalcified tissue. The results show that formalin fixation and EDTA decalcification preserve substantial amounts of mRNA within the tissue. In particular, this study illustrates that it is possible to perform in-situ hybridization on formalin fixed decalcified paraffin embedded tissue.

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.

Nitrogen fixation dynamics of two diazotrophic communities in Mono Lake, California

Science.gov (United States)

Oremland, R.S.

1990-01-01

Two types of diazotrophic microbial communities were found in the littoral zone of alkaline hypersaline Mono Lake, California. One consisted of anaerobic bacteria inhabiting the flocculent surface layers of sediments. Nitrogen fixation (acetylene reduction) by flocculent surface layers occurred under anaerobic conditions, was not stimulated by light or by additions of organic substrates, and was inhibited by O2, nitrate, and ammonia. The second community consisted of a ball-shaped association of a filamentous chlorophyte (Ctenocladus circinnatus) with diazotrophic, nonheterocystous cyanobacteria, as well as anaerobic bacteria (Ctenocladus balls). Nitrogen fixation by Ctenocladus balls was usually, but not always, stimulated by light. Rates of anaerobic dark fixation equaled those in the light under air. Fixation in the light was stimulated by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and by propanil [N-(3,4-dichlorophenyl)propanamide]. 3-(3,4-Dichlorophenyl)-1,1-dimethyl urea-elicited nitrogenase activity was inhibited by ammonia (96%) and nitrate (65%). Fixation was greatest when Ctenocladus balls were incubated anaerobically in the light with sulfide. Dark anaerobic fixation was not stimulated by organic substrates in short-term (4-h) incubations, but was in long-term (67-h) ones. Areal estimates of benthic N2 fixation were measured seasonally, using chambers. Highest rates (~29.3 ??mol of C2H4 m-2 h-1) occurred under normal diel regimens of light and dark. These estimates indicate that benthic N2 fixation has the potential to be a significant nitrogen source in Mono Lake.

Bucking the trend in wolf-dog hybridization: first evidence from europe of hybridization between female dogs and male wolves.

Science.gov (United States)

Hindrikson, Maris; Männil, Peep; Ozolins, Janis; Krzywinski, Andrzej; Saarma, Urmas

2012-01-01

Studies on hybridization have proved critical for understanding key evolutionary processes such as speciation and adaptation. However, from the perspective of conservation, hybridization poses a concern, as it can threaten the integrity and fitness of many wild species, including canids. As a result of habitat fragmentation and extensive hunting pressure, gray wolf (Canis lupus) populations have declined dramatically in Europe and elsewhere during recent centuries. Small and fragmented populations have persisted, but often only in the presence of large numbers of dogs, which increase the potential for hybridization and introgression to deleteriously affect wolf populations. Here, we demonstrate hybridization between wolf and dog populations in Estonia and Latvia, and the role of both genders in the hybridization process, using combined analysis of maternal, paternal and biparental genetic markers. Eight animals exhibiting unusual external characteristics for wolves - six from Estonia and two from Latvia - proved to be wolf-dog hybrids. However, one of the hybridization events was extraordinary. Previous field observations and genetic studies have indicated that mating between wolves and dogs is sexually asymmetrical, occurring predominantly between female wolves and male dogs. While this was also the case among the Estonian hybrids, our data revealed the existence of dog mitochondrial genomes in the Latvian hybrids and, together with Y chromosome and autosomal microsatellite data, thus provided the first evidence from Europe of mating between male wolves and female dogs. We discuss patterns of sexual asymmetry in wolf-dog hybridization.

External factors affecting data acquisition during corneal topography examination.

Science.gov (United States)

González-Méijome, José Manuel; Queirós, Antonio; Jorge, Jorge; Fernandes, Paulo; Cerviño, Alejandro; de Almeida, José Borges

2007-03-01

To analyze the factors affecting data acquisition during corneal topography examination with the Medmont E-300 videokeratoscope and to provide strategies to minimize their effects. Sixty eyes from thirty young adults were examined. A second observer registered incidences with the potential to affect data acquisition. Those factors were correlated with the difficulty of measurements as judged subjectively by the practitioner who performed the examination. Measurements of axial curvature were analyzed to evaluate the variability expressed as intrasession and intersession coefficient of variation and the standard error of the mean (SEM). The level of difficulty rated by the practitioner was in general low, with 70% of the eyes being easy or very easy to measure. For the remaining 30% of the eyes, corneal topography measurements were considered to be difficult (27%) or very difficult (3%). Of the external parameters investigated, only fixation instability (PSEM improved when three readings from each session were considered. The level of subjective difficulty found during videokeratoscopy examination is correlated strongly with fixation instability and the need for head reorientation in the chin rest, whereas tear-related events seem to be less relevant in the practitioner perception of test ease or difficulty. Those factors have relevance in measurement variability.

The deformity correction and fixator-assisted treatment using Ilizarov versus Taylor spatial frame in the foot and ankle

Directory of Open Access Journals (Sweden)

Yudha Manggala

2018-02-01

Full Text Available This study was to report the comparison of outcomes between Ilizarov ring fixator (IRF and Taylor Spatial Frame® (Smith & Nephew, Memphis, Tenn.; TSF in terms of the effectiveness of ankle-foot deformities correction, follow-up results, and complications. Fourteen patients with ankle-foot deformities were corrected using circular external fixation (IRF group = 7 patients; TSF group = 7 patients and related procedures. Baseline data and treatment variables were recorded. The patients’ mean age was 42.9 years. Mean follow-up time was 6.5 months. Most common cause of deformity/traumatic condition was posttraumatic equinus. There were successful results in 8 patients (57.1%, partial successful results in 5 patients (35.7%, and revision-needed in 1 patient (7.1%. TSF group demonstrated significantly higher rate of successful results than IRF group (P=0.033. A trend of lower complication rate was found in TSF group (P=0.286. Deformity corrections using TSF provided significantly better clinical scores and higher rate of successful outcome than conventional IRF.

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)

Distribution of nitrogen fixation and nitrogenase-like sequences amongst microbial genomes

Science.gov (United States)

2012-01-01

Background The metabolic capacity for nitrogen fixation is known to be present in several prokaryotic species scattered across taxonomic groups. Experimental detection of nitrogen fixation in microbes requires species-specific conditions, making it difficult to obtain a comprehensive census of this trait. The recent and rapid increase in the availability of microbial genome sequences affords novel opportunities to re-examine the occurrence and distribution of nitrogen fixation genes. The current practice for computational prediction of nitrogen fixation is to use the presence of the nifH and/or nifD genes. Results Based on a careful comparison of the repertoire of nitrogen fixation genes in known diazotroph species we propose a new criterion for computational prediction of nitrogen fixation: the presence of a minimum set of six genes coding for structural and biosynthetic components, namely NifHDK and NifENB. Using this criterion, we conducted a comprehensive search in fully sequenced genomes and identified 149 diazotrophic species, including 82 known diazotrophs and 67 species not known to fix nitrogen. The taxonomic distribution of nitrogen fixation in Archaea was limited to the Euryarchaeota phylum; within the Bacteria domain we predict that nitrogen fixation occurs in 13 different phyla. Of these, seven phyla had not hitherto been known to contain species capable of nitrogen fixation. Our analyses also identified protein sequences that are similar to nitrogenase in organisms that do not meet the minimum-gene-set criteria. The existence of nitrogenase-like proteins lacking conserved co-factor ligands in both diazotrophs and non-diazotrophs suggests their potential for performing other, as yet unidentified, metabolic functions. Conclusions Our predictions expand the known phylogenetic diversity of nitrogen fixation, and suggest that this trait may be much more common in nature than it is currently thought. The diverse phylogenetic distribution of nitrogenase

Distribution of nitrogen fixation and nitrogenase-like sequences amongst microbial genomes

Directory of Open Access Journals (Sweden)

Dos Santos Patricia C

2012-05-01

Full Text Available Abstract Background The metabolic capacity for nitrogen fixation is known to be present in several prokaryotic species scattered across taxonomic groups. Experimental detection of nitrogen fixation in microbes requires species-specific conditions, making it difficult to obtain a comprehensive census of this trait. The recent and rapid increase in the availability of microbial genome sequences affords novel opportunities to re-examine the occurrence and distribution of nitrogen fixation genes. The current practice for computational prediction of nitrogen fixation is to use the presence of the nifH and/or nifD genes. Results Based on a careful comparison of the repertoire of nitrogen fixation genes in known diazotroph species we propose a new criterion for computational prediction of nitrogen fixation: the presence of a minimum set of six genes coding for structural and biosynthetic components, namely NifHDK and NifENB. Using this criterion, we conducted a comprehensive search in fully sequenced genomes and identified 149 diazotrophic species, including 82 known diazotrophs and 67 species not known to fix nitrogen. The taxonomic distribution of nitrogen fixation in Archaea was limited to the Euryarchaeota phylum; within the Bacteria domain we predict that nitrogen fixation occurs in 13 different phyla. Of these, seven phyla had not hitherto been known to contain species capable of nitrogen fixation. Our analyses also identified protein sequences that are similar to nitrogenase in organisms that do not meet the minimum-gene-set criteria. The existence of nitrogenase-like proteins lacking conserved co-factor ligands in both diazotrophs and non-diazotrophs suggests their potential for performing other, as yet unidentified, metabolic functions. Conclusions Our predictions expand the known phylogenetic diversity of nitrogen fixation, and suggest that this trait may be much more common in nature than it is currently thought. The diverse phylogenetic

Effects of tissue fixation and dehydration on tendon collagen nanostructure.