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Sample records for elastic stable intramedullary

  1. Attritional rupture of extensor pollicis longus: a rare complication following elastic stable intramedullary nailing of a paediatric radial fracture.

    LENUS (Irish Health Repository)

    Sproule, James A

    2011-01-01

    Elastic stable intramedullary nail fixation has become established as an acceptable method of treatment for diaphyseal fractures of both forearm bones in the paediatric population. It is considered safe, minimally invasive and does not compromise physeal growth. We report a case of delayed rupture of extensor pollicis longus due to attrition over the sharp edges of a protruding nail end after elastic stable intramedullary nailing of a paediatric radial diaphyseal fracture.

  2. Pre-bent elastic stable intramedullary nail fixation for distal radial shaft fractures in children.

    Science.gov (United States)

    Ge, Yi-hua; Wang, Zhi-gang; Cai, Hai-qing; Yang, Jie; Xu, Yun-lan; Li, Yu-chan; Zhang, Yu-chen; Chen, Bo-chang

    2010-08-01

    To investigate the functional and radiographic outcomes of pre-bent elastic stable intramedullary nail in treatment of distal radial shaft fractures in children. From January 2006 to December 2008, 18 children with distal radial shaft fracture were treated by close reduction and internal fixation with a pre-bent elastic stable intramedullary nail. The age range was from 5 years to 15 years, with an average of 9 years and 8 months. The minimum follow-up was 12 months. All fractures maintained good alignment postoperatively, and 94.4% (17/18) of the patients regained a full range of rotation of the forearm. One patient has limitation of rotation to less than 10°, this had improved by final follow-up. Complications included soft tissue irritation at the site of nail insertion in one patient and transient scar hypersensitivity in another. Fixation with a pre-bent elastic stable intramedullary nail is an effective, safe and convenient method for treating distal radial shaft fractures in children. © 2010 Tianjin Hospital and Blackwell Publishing Asia Pty Ltd.

  3. Femoral shaft fractures in children: elastic stable intramedullary nailing in 31 cases

    DEFF Research Database (Denmark)

    Houshian, Shirzad; Gøthgen, Charlotte Buch; Pedersen, Niels Wisbech

    2004-01-01

    We report our experience with elastic stable intramedullary titanium nailing (ESIN) of femoral shaft fractures in children. From 1998 to 2001, we treated 31 children (20 boys), median age 6 (4-11) years, with ESIN for 29 closed and 2 grade I open femoral shaft fractures. We reviewed 30 children...... clinically after median 1.5 (1-3) years. Their median hospital stay was 6 (2-20) days. All fractures were radiographically united at a median of 7 (5-9) weeks. The nails were removed in 29 children after a median of 22 (6-38) weeks postoperatively. At follow-up, we found a leg-length discrepancy up to 1 cm...

  4. Median Nerve Palsy following Elastic Stable Intramedullary Nailing of a Monteggia Fracture: An Unusual Case and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Surjit Lidder

    2011-01-01

    Full Text Available Monteggia fractures are rare in children, and subtle radial head dislocations, with minor plastic deformation of the ulna, may be missed in up to a third of cases. Complications of Monteggia fractures-dislocations include persistent radial head dislocation, forearm deformity, elbow stiffness, and nerve palsies at the time of presentation. An unusual case of median nerve palsy following elastic stable intramedullary nailing of a type I Monteggia lesion in a 6-year-old girl is presented, and we highlight that, although most nerve palsies associated with a Monteggia fracture-dislocations are treated expectantly in children, early intervention here probably provided the best outcome.

  5. A new mini-invasive technique in treating pediatric diaphyseal forearm fractures by bioabsorbable elastic stable intramedullary nailing: a preliminary technical report.

    Science.gov (United States)

    Sinikumpu, J-J; Keränen, J; Haltia, A-M; Serlo, W; Merikanto, J

    2013-01-01

    Operative treatment is often indicated in unstable pediatric diaphyseal forearm fractures. Recently minimally invasive reduction and elastic stable intramedullary nailing have been of increasing interest, instead of open reduction and internal fixation with plates. There are several disadvantages of metallic intramedullary implants, such as soft-tissue irritation and a risk of disturbing later imaging. Thus, they are generally removed in later operations. We aimed to develop a new technique to stabilize pediatric forearm fractures by the bioabsorbable intramedullary nailing. We developed a new, two-stage mini-invasive surgical technique to stabilize the unstable diaphyseal fractures in children. The procedure is bioabsorbable elastic stable intramedullary nailing. Ultra-high-strength bioabsorbable intramedullary nails of poly(lactide-co-glycolide) were manufactured for our purpose. The material has been widely proven to be biocompatible and stable enough for fracture treatment as screws and pins. We have used the new technique in the unstable both-bone diaphyseal forearm fractures in children between the ages of 5 and 15 years. We report the technique and our clinical experience in the series of those three cases that have been followed up for at least 12 months. The present series has been randomized for the procedure instead for titanium elastic stable intramedullary nailing, and the series represents a part of ongoing randomized trial. The reported cases operated by the new technique referred good union in the fractured bones and acceptable alignment in the follow-up. Removal of the implants was not required. No troubles with the procedure or implant per se were noticed, indicating good feasibility. One high-energy refracture occurred half year after the primary trauma. Traditional titanium implants were used to control the refracture. We report our preliminary experience of a new surgical mini-invasive procedure to stabilize the unstable pediatric forearm shaft

  6. Additional Tension Screws Improve Stability in Elastic Stable Intramedullary Nailing: Biomechanical Analysis of a Femur Spiral Fracture Model.

    Science.gov (United States)

    Zachert, Gregor; Rapp, Marion; Eggert, Rebecca; Schulze-Hessing, Maaike; Gros, Nina; Stratmann, Christina; Wendlandt, Robert; Kaiser, Martin M

    2015-08-01

    For pediatric femoral shaft fractures, elastic stable intramedullary nailing (ESIN) is an accepted method of treatment. But problems regarding stability with shortening or axial deviation are well known in complex fracture types and heavier children. Biomechanical in vitro testing was performed to determine whether two modified osteosyntheses with an additional tension screw fixation or screw fixation alone without nails could significantly improve the stability in comparison to classical ESIN. A total of 24 synthetic adolescent-sized femoral bone models (Sawbones, 4th generation; Vashon, Washington, United States) with an identical spiral fracture (length 100 mm) were used. All grafts underwent retrograde fixation with two C-shaped steel nails (2C). Of the 24, 8 osteosyntheses were supported by one additional tension screw (2C1S) and another 8 by two screws (2S) in which the intramedullary nails were removed before testing. Each configuration underwent biomechanical testing in 4-point bending, external rotation (ER) and internal rotation (IR). Furthermore, the modifications were tested in axial physiological 9 degrees position for shifting and dynamic compression as well as dynamic load. Both screw configurations (2C1S and 2S) demonstrated a significantly higher stability in comparison to the 2C configuration in 4-point bending (anterior-posterior, 0.95 Nm/mm [2C] spiral fracture model, the stability of ESIN could be significantly improved by two modifications with additional tension screws. If transferred in clinical practice, these modifications might offer earlier weight bearing and less problems of shortening or axial deviation. Georg Thieme Verlag KG Stuttgart · New York.

  7. Slow Recovery of Weight Bearing After Stabilization of Long-Bone Fractures Using Elastic Stable Intramedullary Nails in Children.

    Science.gov (United States)

    Lardelli, Patrizia; Frech-Dörfler, Martina; Holland-Cunz, Stefan; Mayr, Johannes

    2016-03-01

    Stabilization of diaphyseal long-bone fractures using elastic stable intramedullary nails (ESIN) in children promises early mobilization and rapid resumption of full weight bearing. We evaluated the duration of postoperative functional rehabilitation after ESIN, measured by the time from stabilization until first partial weight bearing, full weight bearing, and resumption of school sports. Fifty children with unstable, displaced fractures of the femur or lower leg treated with ESIN between 2002 and 2012 were included in this retrospective analysis. We classified fractures according to the pediatric comprehensive classification of fractures (PCCF). Thirty-five children sustained a femur fracture, and 15 children had a fracture of the lower leg or tibia. The surgeons in charge applied an additional plaster cast in 7 of 15 children who suffered a lower leg fracture. The postoperative time interval until full weight bearing in the group of children who had suffered transverse or short oblique femur fractures was significantly shorter (median: 4.4 weeks; range: 0.1-9.1 weeks) than that in the group who had sustained more complex fracture patterns (median: 6.8 weeks; range: 2.9-13.9 weeks; P = 0.04). Similarly, transverse and short oblique lower leg and tibia fractures required less time until full weight bearing (median: 4.1 weeks; range 2.7-6.0 weeks) than complex lower leg fractures (median: 6.1 weeks; range: 1.3-12.9 weeks; P = 0.04). ESIN proved fairly effective in restoring full weight bearing in transverse or short oblique fractures of the lower extremities but was less effective in complex fractures.

  8. Elastic stable intramedullary nailing is the best treatment of unicameral bone cysts of the long bones in children?: Prospective long-term follow-up study.

    Science.gov (United States)

    de Sanctis, Nando; Andreacchio, Antonio

    2006-01-01

    Since Virchow first described the unicameral bone cyst (UBC) in 1876, several methods for management were proposed. Currently performed surgical procedures include curettage combined with bone grafting, allografting with freeze-dried crushed cortical bone, use of homologous cancellous bone chips, the application of high-porosity hydroxyapatite, and cryosurgery. Decompression with multiple drill holes and intralesional injections of either steroids or bone marrow have also been used to treat UBC, with variable success rates. Elastic stable intramedullary nailing for the treatment of UBC in long bones has been rapidly gaining popularity. Elastic stable intramedullary nailing for the treatment of a UBC was performed in 56 patients between 1994 and 2003. The follow-up is between 2.1 and 11 years. Nine children were excluded because of short period of follow-up or were lost. The study population consisted of 47 children. The cyst was located in the humerus in 36 patients, in the femur in 11. The mean age of the patients at the time of surgery was 8.9 years. Results were evaluated on plain radiographs according to the classification system of Capanna et al. In our study population of 47 UBCs, 31 (65.9 %) were classified as completely healed, and 16 (34.1%) were healed with residual radiolucency. No recurrence or no response was observed. Each lesion responded to treatment after the nailing. This method can solve in time the pathology, and we feel that, with skilled hands, this method is the best one for UBC treatment in the long bones of the children.

  9. Elastic stable intramedullary nailing of femoral shaft fractures in children: Particularities and results at Sylvanus Olympio teaching hospital of Lomé, Togo

    Directory of Open Access Journals (Sweden)

    Akakpo-Numado Gamedzi Komlatsè

    2014-01-01

    Full Text Available Introduction: The elastic stable intramedullary nailing (ESIN presently seems the best technique in the surgical treatment of femoral shaft fractures (FSF in >6-year-old children. We hereby report technical difficulties and therapeutic results after our first 8 years of experience. Patients and Methods: It′s a retrospective study over a period of 8 years from January 2005 to December 2012 in the Paediatric Surgery Department of Sylvanus Olympio Teaching Hospital of Lomé. Indications, technical particularities and results were studied. Results: There were 32 patients, 17 were boys and 15 were girls, with a mean age of 11 years old. The mean time to surgery was 21 days (range: 14 and 51 days. A callus was always removed before reduction. The osteosynthesis was stable in 22 cases, but in 10 others, it had been completed with a cast immobilisation. The operation needed a blood transfusion in 18 cases. With a mean follow-up of 3.5 years, the results were excellent in 29 patients (90.63% and good in 3 patients (9.37%. Conclusion: Although undertaking an ESIN can be difficult, due to the lack of adequate equipment the procedure produces satisfactory outcome.

  10. Modification of elastic stable intramedullary nailing with a 3rd nail in a femoral spiral fracture model - results of biomechanical testing and a prospective clinical study.

    Science.gov (United States)

    Kaiser, Martin M; Stratmann, Christine; Zachert, Gregor; Schulze-Hessing, Maaike; Gros, Nina; Eggert, Rebecca; Rapp, Marion

    2014-01-08

    Elastic stable intramedullary nailing (ESIN) is the standard treatment for displaced diaphyseal femoral fractures in children. However, high complication rates (10-50%) are reported in complex fractures. This biomechanical study compares the stiffness with a 3rd nail implanted to that in the classical 2C-shaped configuration and presents the application into clinical practice. For each of the 3 configurations of ESIN-osteosynthesis with titanium nails eight composite femoral grafts (Sawbones®) with an identical spiral fracture were used: 2C configuration (2C-shaped nails, 2 × 3.5 mm), 3CM configuration (3rd nail from medial) and 3CL configuration (3rd nail from lateral). Each group underwent biomechanical testing in 4-point bending, internal/external rotation and axial compression. 2C and 3CM configurations showed no significant differences in this spiroid type fracture model. 3CL had a significantly higher stiffness during anterior-posterior bending, internal rotation and 9° compression than 2C, and was stiffer in the lateral-medial direction than 3CM. The 3CL was less stable during p-a bending and external rotation than both the others. As biomechanical testing showed a higher stability for the 3CL configuration in two (a-p corresponding to recurvation and 9° compression to shortening) of three directions associated with the most important clinical problems, we added a 3rd nail in ESIN-osteosynthesis for femoral fractures. 11 boys and 6 girls (2.5-15 years) were treated with modified ESIN of whom 12 were '3CL'; due to the individual character of the fractures 4 patients were treated with '3CM' (third nail from medial) and as an exception 1 adolescent with 4 nails and one boy with plate osteosynthesis. No additional stabilizations or re-operations were necessary. All patients achieved full points in the Harris-Score at follow-up; no limb length discrepancy occurred. The 3CL configuration provided a significantly higher stiffness than 2C and 3CM configurations

  11. Elastic robust intramedullary nailing for forearm fracture in children

    Directory of Open Access Journals (Sweden)

    Wasem, Jürgen

    2006-01-01

    Full Text Available Background: Forearm fractures are the most common fractures in children (23% of all fractures. Basically there are two treatment options available for diaphyseal forearm fractures in children: closed reduction with cast immobilisation (conservative therapy and the elastic stable intramedullary nailing (ESIN. Treatment decision is influenced by the doctor's estimation of fracture instability. Stable fractures can be treated conservatively whereas instable forearm shaft fractures can be treated according the following three treatment strategies: 1. conservative therapy in an outpatient setting 2. conservative therapy in the operating room in attendance to change to ESIN in case that no stabilisation can be achieved with cast immobilisation 3. immediate treatment with ESIN in the operating room. Objectives: Aim of this Health Technology Assessment (HTA report is to assess and report the published evidence concerning effectiveness and cost-effectiveness of ESIN as a treatment option for diaphyseal forearm fractures in children and to identify future research need. Important parameters for the assessment of effectiveness are objective parameters (axis deviation, losses of motion, and numbers of reductions in case of redislocations and subjective parameters (pain or impairment in quality of life. Furthermore, a health economic evaluation shall be done which refers to the costs of the different therapy strategies. Methods: An extensive, systematic literature search in medical, economic, and HTA literature databases was performed. Relevant data were extracted and synthesised. Results: Three cohort studies and seven case series have been identified. Controlled clinical studies, systematic reviews and/or HTA reports that gave evidence to answer the own study question have not been found. The identified studies partly differed in respect of defined indication for ESIN, study population and treatment strategies. For that reason comparability of results was

  12. Intramedullary nailing of clavicular midshaft fractures in adults using titanium elastic nail

    Directory of Open Access Journals (Sweden)

    CHEN Qing-yv

    2012-02-01

    Full Text Available 【Abstract】 Objective: Studies showed elastic stable intramedullary nailing (ESIN of displaced midclavicular fractures has excellent outcomes, as well as high complication rates and specific problems. The aim was to discuss ESIN of midshaft clavicular fractures. Methods: Totally 60 eligible patients (aged 18-63 years were randomized to either ESIN group or non-operative group between January 2007 and May 2008. Clavicular shortening was measured after trauma and osseous consolidation. Radiographic union and complications were assessed. Function analysis including Constant shoulder scores and disabilities of the arm, shoulder and hand (DASH scores were performed after a 15-month follow-up. Results: ESIN led to a signifcantly shorter time to union, especially for simple fractures. In ESIN group, all patients got fracture union, of which 5 cases had medial skin irritation and 1 patient needed revision surgery because of implant failure. In the nonoperative group, there were 3 nonunion cases and 2 symptomatic malunions developed requiring corrective osteotomy. At 15 months after intramedullary stabilization, patients in the ESIN group were more satisfied with the appearance of the shoulder and overall outcome, and they benefited a lot from the great improvement of post-traumatic clavicular shortening. Furthermore, DASH scores were lower and Constant scores were significantly higher in contrast to the non-operative group. Conclusion: ESIN is a safe minimally invasive surgical technique with lower complication rate, faster return to daily activities, excellent cosmetic and better functional results, restoration of clavicular length for treating mid-shaft clavicular fractures, resulting in high overall satisfaction, which can be regard as an alternative to plate fixation or nonoperative treatment of mid-shaft clavicular fractures. Key words: Clavicle; Fracture fixation intramedu- llary; Outcome assessment

  13. Intramedullary nailing of clavicular midshaft fractures in adults using titanium elastic nail.

    Science.gov (United States)

    Chen, Qing-Yu; Kou, Dong-Quan; Cheng, Xiao-Jie; Zhang, Wei; Wang, Wei; Lin, Zhang-Qin; Cheng, Shao-Wen; Shen, Yue; Ying, Xiao-Zhou; Peng, Lei; Lv, Chuan-Zhu

    2011-01-01

    Studies showed elastic stable intramedullary nailing (ESIN) of displaced midclavicular fractures has excellent outcomes, as well as high complication rates and specific problems. The aim was to discuss ESIN of midshaft clavicular fractures. Totally 60 eligible patients (aged 18-63 years) were randomized to either ESIN group or non-operative group between January 2007 and May 2008. Clavicular shortening was measured after trauma and osseous consolidation. Radiographic union and complications were assessed. Function analysis including Constant shoulder scores and disabilities of the arm, shoulder and hand (DASH) scores were performed after a 15-month follow-up. ESIN led to a signifcantly shorter time to union, especially for simple fractures. In ESIN group, all patients got fracture union, of which 5 cases had medial skin irritation and 1 patient needed revision surgery because of implant failure. In the nonoperative group, there were 3 nonunion cases and 2 symptomatic malunions developed requiring corrective osteotomy. At 15 months after intramedullary stabilization, patients in the ESIN group were more satisfied with the appearance of the shoulder and overall outcome, and they benefited a lot from the great improvement of post-traumatic clavicular shortening. Furthermore, DASH scores were lower and Constant scores were significantly higher in contrast to the non-operative group. ESIN is a safe minimally invasive surgical technique with lower complication rate, faster return to daily activities, excellent cosmetic and better functional results, restoration of clavicular length for treating mid-shaft clavicular fractures, resulting in high overall satisfaction, which can be regard as an alternative to plate fixation or nonoperative treatment of mid-shaft clavicular fractures.

  14. Paediatric diaphyseal femur fracture treated with intramedullary titanium elastic nail system

    Directory of Open Access Journals (Sweden)

    Shrawan Kumar Thapa

    2015-11-01

    Full Text Available noBackground & Objectives: Over the few years there has been a marked increase in the use of intramedullary fixation in the management of fracture of shaft of femur in children. The goals should be to stabilize the fracture, to control length and alignment, to promote bone healing and to minimize the morbidity and complications for the child. In this prospective study we intend to evaluate the functional and radiological outcome of diaphyseal fracture of shaft of femur treated with elastic intramedullary nail.Materials & Methods: All 56 patients with diaphyseal fracture shaft of femur were treated with titanium elastic nail and followed for period of 32 weeks.Results: The In this study, outcome was assessed by using Flynn’s criteria of titanium flexible nail outcome score and we found excellent result in 49 cases, satisfactory in six cases and poor in one case. We faced one major complication in form of implant failure and six minor complications inform of superficial wound infection.Conclusion: Elastic intramedullary nail used in treatment of diaphyseal fracture shaft of femur yield excellent functional and radiological outcome. It is easy and simple procedure has low rate of complication. It is physeal-protective, cost effective, does not involve heavy instrumentation and can be performed in small set up. It has minimal risk of infection and no risk of injury to the neurovascular structure.JCMS Nepal. 2015; 11(2:20-22

  15. Screw elastic intramedullary nail for the management of adult forearm fractures

    Directory of Open Access Journals (Sweden)

    Wasudeo Gadegone

    2012-01-01

    Full Text Available Background: The failure of the conventional nailing of both forearm bones or isolated fractures of radius and ulna pose a potential problem of nail migration and rotational instability, despite the best reduction. The purpose of this paper is to evaluate the results of screw elastic intramedullary nail for the treatment of adult diaphyseal fractures of both forearm bones, which effectively addresses the problems associated with the conventional nailing systems for the forearm fractures. Materials and Methods: Seventy-six adults with forearm fractures (radius and ulna or isolated fracture of the single bone were retrospectively evaluated. Fifty males and 26 females with the mean age of 38 years (range, 18-70 years underwent closed reduction and screw intramedullary nail fixation. Ten patients required limited open reduction. The fractures were classified according to the AO/OTA system. The average followup was 12 months (range, 6 to 18 months. Results: The mean surgical time was 45 minutes (35 to 65 minutes. The meantime to union was 14 weeks (10-21 weeks. The results were graded as excellent in 50, good in 18 patients, and acceptable in eight patients, using the criteria of Grace and Eversman. We had superficial infection in three cases, one case of delayed infection, painful bursa in two cases, delayed union in two cases, malunion with dislocation of the DRUJ in two cases, injury to the extensor tendon of the thumb in one case, and one case of incomplete radioulnar synostosis. Conclusion: Closed reduction and internal fixation of forearm fractures by screw intramedullary nails reestablishes the near normal relationship of the fractured fragments. Screw intramedullary nail effectively controls both rotatory forces and the migration of the nail. It produces excellent clinical results in isolated fractures of either bones, as well as both bones of the forearm in adults.

  16. Elastic intramedullary nailing and DBM-Bone marrow injection for the treatment of simple bone cysts

    Science.gov (United States)

    Kanellopoulos, Anastasios D; Mavrogenis, Andreas F; Papagelopoulos, Panayiotis J; Soucacos, Panayotis N

    2007-01-01

    Background Simple or unicameral bone cysts are common benign fluid-filled lesions usually located at the long bones of children before skeletal maturity. Methods We performed demineralized bone matrix and iliac crest bone marrow injection combined with elastic intramedullary nailing for the treatment of simple bone cysts in long bones of 9 children with a mean age of 12.6 years (range, 4 to 15 years). Results Two of the 9 patients presented with a pathological fracture. Three patients had been referred after the failure of previous treatments. Four patients had large lesions with impending pathological fractures that interfered with daily living activities. We employed a ratio to ascertain the severity of the lesion. The extent of the lesion on the longitudinal axis was divided with the normal expected diameter of the long bone at the site of the lesion. The mean follow-up was 77 months (range, 5 to 8 years). All patients were pain free and had full range of motion of the adjacent joints at 6 weeks postoperatively. Review radiographs showed that all 7 cysts had consolidated completely (Neer stage I) and 2 cysts had consolidated partially (Neer stage II). Until the latest examination there was no evidence of fracture or re-fracture. Conclusion Elastic intramedullary nailing has the twofold benefits of continuous cyst decompression, and early immediate stability to the involved bone segment, which permits early mobilization and return to the normal activities of the pre-teen patients. PMID:17916249

  17. Elastic intramedullary nailing and DBM-Bone marrow injection for the treatment of simple bone cysts

    Directory of Open Access Journals (Sweden)

    Papagelopoulos Panayiotis J

    2007-10-01

    Full Text Available Abstract Background Simple or unicameral bone cysts are common benign fluid-filled lesions usually located at the long bones of children before skeletal maturity. Methods We performed demineralized bone matrix and iliac crest bone marrow injection combined with elastic intramedullary nailing for the treatment of simple bone cysts in long bones of 9 children with a mean age of 12.6 years (range, 4 to 15 years. Results Two of the 9 patients presented with a pathological fracture. Three patients had been referred after the failure of previous treatments. Four patients had large lesions with impending pathological fractures that interfered with daily living activities. We employed a ratio to ascertain the severity of the lesion. The extent of the lesion on the longitudinal axis was divided with the normal expected diameter of the long bone at the site of the lesion. The mean follow-up was 77 months (range, 5 to 8 years. All patients were pain free and had full range of motion of the adjacent joints at 6 weeks postoperatively. Review radiographs showed that all 7 cysts had consolidated completely (Neer stage I and 2 cysts had consolidated partially (Neer stage II. Until the latest examination there was no evidence of fracture or re-fracture. Conclusion Elastic intramedullary nailing has the twofold benefits of continuous cyst decompression, and early immediate stability to the involved bone segment, which permits early mobilization and return to the normal activities of the pre-teen patients.

  18. Comparative Study Using Intramedullary K-wire Fixation Over Titanium Elastic Nail in Paediatric Shaft Femur Fractures.

    Science.gov (United States)

    Kumar, Sanjiv; Anand, Tushar; Singh, Sudhir

    2014-11-01

    Fracture shaft femur is common paediatric trauma leading to significant morbidity. Conservative treatments available are associated with prolonged periods of immobilization. Use of flexible intramedullary implant allows early rehabilitation in diaphyseal fractures of femur in children. The aim of the present study is to compare fixation of diaphyseal femur fracture by titanium elastic nail and intramedullary K-wires in children. Prospective randomized study in a tertiary care hospital. Fifty-two children between 6 years and 14 years of age with femoral shaft fracture were assigned either in Group I or Group II based on computer generated random numbers. In Group I closed percutaneous intramedullary K- wire fixation and in Group II closed percutaneous intramedullary titanium elastic nail was used to fix the fractures. Partial weight bearing was allowed after 6 weeks of surgery and full weight bearing at clinico-radiological union. Average time of radiological union was 6 to 10 weeks in both groups. In both the groups two cases had entry site irritation which resolved with early implant removal. One case in both the groups had unacceptable mal-alignment. Both the groups had few cases of limb-length discrepancy, which was in acceptable limit, except two cases of TENS. There was no statistically significant difference between the results of both the groups. But, using K-wires significantly reduced the cost of treatment. Most of such fractures in our society are neglected because of high cost of treatment. Providing a cheaper alternative in form of K-wires may be beneficial for the patients from low socio-economic status.

  19. Surgical approach for elastic stable intramedullary nail in pediatric radius shaft fracture

    DEFF Research Database (Denmark)

    Nørgaard, Sandra L.; Schødt Riber, Sara; Danielsson, Frederik B.

    2018-01-01

    . An electronic search of databases was performed. Titles of articles were screened, and abstracts and full text were read. Data were extracted in terms of demographics and complications. The dorsal approach had a 2.6% rate of extensor pollicis longus tendon rupture, whereas the lateral approach had a 2.9% rate...

  20. ediatric femoral shaft fractures treated by flexible intramedullary nailing.

    Science.gov (United States)

    Kapil Mani, K C; Dirgha Raj, R C; Parimal, Acharya

    2015-01-01

    Nowadays pediatric femoral fractures are more commonly managed with operative treatment rather than conservative treatment because of more rapid recovery and avoidance of prolonged immobilization. Children between the ages of 5-13 years are treated either by traction plus hip spica and flexible/elastic stable retrograde intramedullary nail, or external fixators in the case of open fractures. The aim of this study is to evaluate the outcome of pediatric femoral shaft fractures treated by stainless steel flexible intramedullary nail in children between 5 and 13 years of age. There were 32 cases of femoral shaft fractures which were all fixed with stainless steel flexible intramedullary nail under fluoroscopy. Long leg cast was applied at the time of fixation. Partial weight bearing was started 2 weeks after surgery. Patients were evaluated in follow-up study to observe the alignment of fracture, infection, delayed union, nonunion, limb length discrepancy, motion of knee joint, and time to unite the fracture. We were able to follow up 28 out of 32 patients. The patients were 8.14 years of age on average. The mean hospital stay after operation was 4 days and fracture union time was 9.57 weeks. There were 3 cases of varus angulation, 2 cases of anterior angulation, and 4 cases of limb lengthening. Patients aged between 5 and 13 years treated with flexible intramedullary nail for closed femoral shaft fracture have rapid union and recovery, short rehabilitation period, less immobilization and psychological impact, and cost-effective.

  1. Humeral Shaft Fracture: Intramedullary Nailing.

    Science.gov (United States)

    Konda, Sanjit R; Saleh, Hesham; Fisher, Nina; Egol, Kenneth A

    2017-08-01

    This video demonstrates the technique of intramedullary nailing for a humeral shaft fracture. The patient is a 30-year-old man who sustained a gunshot wound to his right arm. The patient was indicated for humeral nailing given the comminuted nature of the diaphysis and to allow for minimal skin incisions. Other relative indications include soft-tissue compromise about the arm precluding a large surgical exposure. This video presents a case of a comminuted humeral shaft fracture treated with an intramedullary nail. Anatomic reduction and stable fixation was obtained with this technique. This case demonstrates a soft-tissue sparing technique of humeral shaft fixation using a humeral intramedullary nail. The technique is easy to perform and has significant benefits in minimizing surgical exposure, decreasing operative time, and decreasing blood loss. In the correct clinical setting, humeral nailing provides an expeditious form of fixation that restores length, alignment, and rotation of the fracture humeral diaphysis.

  2. Intramedullary capillary haemangioma.

    LENUS (Irish Health Repository)

    Kelleher, T

    2012-02-03

    Intramedullary capillary haemangioma is extremely rare and only four cases have been previously reported. We describe a further case, outlining the clinical, radiological, surgical and pathological features.

  3. Stable and high order accurate difference methods for the elastic wave equation in discontinuous media

    KAUST Repository

    Duru, Kenneth

    2014-12-01

    © 2014 Elsevier Inc. In this paper, we develop a stable and systematic procedure for numerical treatment of elastic waves in discontinuous and layered media. We consider both planar and curved interfaces where media parameters are allowed to be discontinuous. The key feature is the highly accurate and provably stable treatment of interfaces where media discontinuities arise. We discretize in space using high order accurate finite difference schemes that satisfy the summation by parts rule. Conditions at layer interfaces are imposed weakly using penalties. By deriving lower bounds of the penalty strength and constructing discrete energy estimates we prove time stability. We present numerical experiments in two space dimensions to illustrate the usefulness of the proposed method for simulations involving typical interface phenomena in elastic materials. The numerical experiments verify high order accuracy and time stability.

  4. Primary malignant intramedullary lymphoma

    International Nuclear Information System (INIS)

    Orrego P, E.; Heinicke Y, H.; Arbaiza A, D.; Yepez R, V.

    1999-01-01

    A case of primary malignant intramedullary lymphoma, localized in the dorsal part of the spinal cord is presented. The clinical symptoms were associated with motor and sensitive deficit. Clinical investigations excluded the presence of lymphoma in other locations in the central nervous system and the extra neural organs. Postoperative radiotherapy and chemotherapy improved relict neurological symptoms. (authors)

  5. Theoretical study of elastic electron scattering off stable and exotic nuclei

    International Nuclear Information System (INIS)

    Roca-Maza, X.; Centelles, M.; Salvat, F.; Vinas, X.

    2008-01-01

    Results for elastic electron scattering by nuclei, calculated with charge densities of Skyrme forces and covariant effective Lagrangians that accurately describe nuclear ground states, are compared against experiment in stable isotopes. Dirac partial-wave calculations are performed with an adapted version of the ELSEPA package. Motivated by the fact that studies of electron scattering off exotic nuclei are intended in future facilities in the commissioned GSI and RIKEN upgrades, we survey the theoretical predictions from neutron-deficient to neutron-rich isotopes in the tin and calcium isotopic chains. The charge densities of a covariant interaction that describes the low-energy electromagnetic structure of the nucleon within the Lagrangian of the theory are used to this end. The study is restricted to medium- and heavy-mass nuclei because the charge densities are computed in mean-field approach. Because the experimental analysis of scattering data commonly involves parameterized charge densities, as a surrogate exercise for the yet unexplored exotic nuclei, we fit our calculated mean-field densities with Helm model distributions. This procedure turns out to be helpful to study the neutron-number variation of the scattering observables and allows us to identify correlations of potential interest among some of these observables within the isotopic chains

  6. Treatment of pediatric femoral shaft fractures by stainless steel and titanium elastic nail system: A randomized comparative trial

    Directory of Open Access Journals (Sweden)

    Tank Gyaneshwar

    2016-08-01

    Conclusion: Majority of paediatric femoral shaft fractures are now treated operatively by elastic stable intramedullary nails. Operative intervention results in a shorter hospital stay and has economic and social benefits over conservative treatment. The cost of stainless steel nail is one third the cost of titanium nail. However, the clinico-radiological results are not significantly different between titanium and stainless steel nails at one year follow-up as observed by our study.

  7. Intramedullary tuberculoma: A case report

    International Nuclear Information System (INIS)

    Maamar, M.; El Quessar, A.; El Fatemi, N.; El Hassani, My R.; Chakir, N.; Jiddane, M.

    2007-01-01

    Study design: We report a case of intra-medullary tuberculoma in a 22 year-old man with progressive paraparesis and sphincter dysfunction. Objectives: To present a case of intra-medullary tuberculosis and to describe the MRI's contribution to the diagnosis. Summary of background data: Intra-medullary spinal tuberculoma is a rare form of central nervous system tuberculosis. The subject and diagnosis methods: The patient, a 22 year-old man, presented with an intra-medullary tuberculoma of the dorsal spinal cord diagnosed after 6 month history of progressive paraparesis and sphincter dysfunction. MRI visualized ring enhancement of the intra-medullary dorsal lesion. Results: Total resection of the intra-medullary mass was performed through a posterior myelotomy. Histological examination revealed a granulomatous necrosis with caseum. The patient was treated with four anti-tuberculosis drugs in association with corticotherapy. The paraparesis and sphincter dysfunction improved. Conclusions: Intra-medullary spinal tuberculoma is rare, but must be considered in the differential diagnosis of spinal cord compression

  8. Stable and high order accurate difference methods for the elastic wave equation in discontinuous media

    KAUST Repository

    Duru, Kenneth; Virta, Kristoffer

    2014-01-01

    to be discontinuous. The key feature is the highly accurate and provably stable treatment of interfaces where media discontinuities arise. We discretize in space using high order accurate finite difference schemes that satisfy the summation by parts rule. Conditions

  9. Comprehensive global evolution of intramedullary nailing of ...

    African Journals Online (AJOL)

    there has been great changes in design, materials and basic science ... proposed that the length of intramedullary implants be maximized to ... as intramedullary implant in 1917 (8). .... micro-movements and intermittent compression during.

  10. [Intramedullary osteosynthesis of distal metacarpal fractures with curved wires].

    Science.gov (United States)

    Schlageter, M; Winkel, R; Porcher, R; Haas, H G

    1997-07-01

    When intramedullary pinning is used to treat metacarpal fractures, as recently described by Förstner (1994) and Foucher (1995), the closed reduction technique developed by Jahss (1938) is applied in the same way as for conservative fracture treatment. It is not always possible to achieve complete anatomical reduction using this closed technique. The intramedullary pinning technique, that we have applied since 1989, involves a Kirschner wire which is bent at one end. Apart from reducing the fracture, the pre-set Kirschner wire serves as a butressing internal fixator. The elastic clamping of the wire acts as an internal wire spring splint, permitting early mobilisation. We have operated on 62 metacarpal fractures using the above-mentioned technique over a period of 6 years until 1995. Anatomic reduction was realized in 50 of 62 fractures. In the follow-up of 32 fractures, we noticed four complications: one infection, two paraesthesias, and one non-union.

  11. [Intramedullary stabilisation of clavicula fractures].

    Science.gov (United States)

    Prokop, A; Schiffer, G; Jubel, A; Chmielnicki, M

    2013-10-01

    With an incidence of 64/100,000, clavicular shaft fractures are one of the most common fractures. Intramedullary fixation with Prevot nails was initially reported in the late 1990s. This procedure offers minimally invasive stabilization of the fracture, thus enabling immediate mobilization and rapid loading capacity. Using a case study, the positioning and procedure are demonstrated on video. The intramedullary implant accommodates the varying tension loading of the clavicle. This treatment is ideal for clavicular fractures with 2-3 fragments. Compared to patients treated conservatively, operated patients achieve more rapid and improved mobility. Employment disability is shorter, and malunion occurs less frequently. Georg Thieme Verlag KG Stuttgart · New York.

  12. Multiple intramedullary nailing of proximal phalangeal fractures of hand

    Directory of Open Access Journals (Sweden)

    Patankar Hemant

    2008-01-01

    Full Text Available Background: Proximal phalangeal fractures are commonly encountered fractures in the hand. Majority of them are stable and can be treated by non-operative means. However, unstable fractures i.e. those with shortening, displacement, angulation, rotational deformity or segmental fractures need surgical intervention. This prospective study was undertaken to evaluate the functional outcome after surgical stabilization of these fractures with joint-sparing multiple intramedullary nailing technique. Materials and Methods: Thirty-five patients with 35 isolated unstable proximal phalangeal shaft fractures of hand were managed by surgical stabilization with multiple intramedullary nailing technique. Fractures of the thumb were excluded. All the patients were followed up for a minimum of six months. They were assessed radiologically and clinically. The clinical evaluation was based on two criteria. 1. total active range of motion for digital functional assessment as suggested by the American Society for Surgery of Hand and 2. grip strength. Results: All the patients showed radiological union at six weeks. The overall results were excellent in all the patients. Adventitious bursitis was observed at the point of insertion of nails in one patient. Conclusion: Joint-sparing multiple intramedullary nailing of unstable proximal phalangeal fractures of hand provides satisfactory results with good functional outcome and fewer complications.

  13. Intramedullary tumours in patients with neurofibromatosis type 2: MRI features associated with a favourable prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Rennie, A.T.M. [Department of Neuroradiology, West Wing, John Radcliffe Hospital, Headington, Oxford (United Kingdom)], E-mail: atmrennie@hotmail.com; Side, L. [Department of Clinical Genetics, Churchill Hospital, Headington, Oxford (United Kingdom); Kerr, R.S.C. [Department of Neurosurgery, West Wing, John Radcliffe Hospital, Headington, Oxford (United Kingdom); Anslow, P.; Pretorius, P. [Department of Neuroradiology, West Wing, John Radcliffe Hospital, Headington, Oxford (United Kingdom)

    2008-02-15

    Aim: To assess the magnetic resonance imaging (MRI) features and natural history of intramedullary tumours in patients with neurofibromatosis type 2 (NF2). Materials and methods: Eleven NF2 patients with intramedullary spinal cord tumours were identified from the database of the multidisciplinary NF2 clinic. All the imaging studies of these patients were individually reviewed by two neuroradiologists to evaluate the size, number, location, imaging characteristics, and interval growth of the intramedullary tumours. Results: Two of the 11 patients had lesions that required surgery. Both these lesions were in the cervical region, and extended over three and five segments respectively. Nine patients with a mean imaging follow-up period of 77 months had lesions that remained stable, apart from the development of small peritumoral cysts in three. The lesions were well circumscribed, often multiple, usually less than 1 cm in diameter, and were most frequently found in the cervical cord. Conclusion: The majority of intramedullary tumours in NF2 patients are very slow growing and share certain MRI features that differ from those of progressive or symptomatic lesions.

  14. MR Imaging in intramedullary cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, H.; Patwardhan, V.; Patankar, T.; Prasad, S. [Dept. of Radiology, King Edward VII Memorial Hospital, Parel, Mumbai (India); Shah, J.; Patkar, D. [Dept. of Radiology, Dr. Balabhai Nanavati Hospital and Research Center, Mumbai (India); Castillo, M. [Dept. of Neuroradiology, Univ. of North Carolina (United States)

    2001-11-01

    Although intramedullary spinal cord cysticercosis (IMC) is uncommon, its presence is being increasingly recognised by magnetic resonance imaging. We studied six patients from an endemic region and present the MRI features and clinical correlation of IMC. Six patients who presented with para- or quadriplegia were studied by contrast enhanced spinal MRI. Prompted by the spinal lesions, all patients underwent brain MRI. Clinical data and laboratory studies were reviewed in all patients. Definite diagnosis was established in the form of response to drug therapy (n=4) and histopathology (n=2). Follow-up MRI studies of spine and brain were obtained in four patients 2 months after they started medical treatment, regardless of surgery. Five patients showed fusiform and focal enlargement of the spinal cord (cervical 2, thoracic 3). Well-defined cysts with a slightly hyperintense mural nodule were identified in five patients in T1-weighted images (T1WI). All cysts were hyperintense on T2WI and merged with the surrounding oedema. Oedema extended one to three vertebral levels above or below the cyst. Post-contrast T1WI showed well-defined, ring enhancing lesions with smooth walls in all patients. Symptoms in all patients correlated with the level of the lesions. Brain studies demonstrated lesions in just two patients. Histopathological confirmation was obtained in two patients. Follow-up spinal MRI was normal in two patients, following 2 months of treatment while residual and smaller lesions were seen in two patients. Two patients were asymptomatic and denied follow-up MRI. MRI of spinal cysticercosis were typical of and similar to those seen in cerebral lesions in our patients and corresponded to the level of symptoms. All cysts were surrounded by oedema. Two of four patients showed residual lesions after 2 months of therapy and 33% of patients showed concomitant intracranial lesions. (orig.)

  15. MR Imaging in intramedullary cysticercosis

    International Nuclear Information System (INIS)

    Parmar, H.; Patwardhan, V.; Patankar, T.; Prasad, S.; Shah, J.; Patkar, D.; Castillo, M.

    2001-01-01

    Although intramedullary spinal cord cysticercosis (IMC) is uncommon, its presence is being increasingly recognised by magnetic resonance imaging. We studied six patients from an endemic region and present the MRI features and clinical correlation of IMC. Six patients who presented with para- or quadriplegia were studied by contrast enhanced spinal MRI. Prompted by the spinal lesions, all patients underwent brain MRI. Clinical data and laboratory studies were reviewed in all patients. Definite diagnosis was established in the form of response to drug therapy (n=4) and histopathology (n=2). Follow-up MRI studies of spine and brain were obtained in four patients 2 months after they started medical treatment, regardless of surgery. Five patients showed fusiform and focal enlargement of the spinal cord (cervical 2, thoracic 3). Well-defined cysts with a slightly hyperintense mural nodule were identified in five patients in T1-weighted images (T1WI). All cysts were hyperintense on T2WI and merged with the surrounding oedema. Oedema extended one to three vertebral levels above or below the cyst. Post-contrast T1WI showed well-defined, ring enhancing lesions with smooth walls in all patients. Symptoms in all patients correlated with the level of the lesions. Brain studies demonstrated lesions in just two patients. Histopathological confirmation was obtained in two patients. Follow-up spinal MRI was normal in two patients, following 2 months of treatment while residual and smaller lesions were seen in two patients. Two patients were asymptomatic and denied follow-up MRI. MRI of spinal cysticercosis were typical of and similar to those seen in cerebral lesions in our patients and corresponded to the level of symptoms. All cysts were surrounded by oedema. Two of four patients showed residual lesions after 2 months of therapy and 33% of patients showed concomitant intracranial lesions. (orig.)

  16. Hydrocephalus: a rare initial manifestation of sporadic intramedullary hemangioblastoma : Intramedullary hemangioblastoma presenting as hydrocephalus.

    Science.gov (United States)

    Morais, Barbara Albuquerque; Cardeal, Daniel Dante; Ribeiro E Ribeiro, Renan; Frassetto, Fernando Pereira; Andrade, Fernanda Goncalves; Matushita, Hamilton; Teixeira, Manoel Jacobsen

    2017-08-01

    Intramedullary hemangioblastomas are rare benign vascular tumors, infrequent in pediatric patients. Clinical symptoms vary according to the age of presentation, tumor size, location, and concomitant syringomyelia. This is the second reported case of hemangioblastoma presenting with acute hydrocephalus. A 3-month-old infant with acute hydrocephalus was asymptomatic after a ventriculoperitoneal shunt was placed. She returned 3 months later with irritability, acute paraplegia, and respiratory distress. Magnetic resonance imaging (MRI) showed an intramedullary T8-T9 tumor with syringomyelia. She underwent surgical resection with good results during the 6-month follow-up. Intramedullary tumors may present as hydrocephalus and other nonspecific symptoms, with invariably delayed diagnosis in children, but must be considered in suspicious cases.

  17. Spinal intramedullary ependymoma: surgical approaches and outcome.

    Science.gov (United States)

    Borges, Lawrence F

    2018-02-01

    Intramedullary ependymomas are uncommon tumors that can occur within the medullary substance of the spinal cord. Despite this difficult location, they are typically benign tumors that can most often be removed completely with an acceptable surgical risk. Therefore, the recommended management approach is usually surgical excision. This review will consider the historical context in which surgeons began treating these tumors and then review the more recent literature that guides their current management.

  18. Treatments of intramedullary spinal cord tumors

    Energy Technology Data Exchange (ETDEWEB)

    Ueyama, Kazumasa; Okada, Akihiro; Echigoya, Naoki; Yokoyama, Toru; Harata, Seiko [Hirosaki Univ., Aomori (Japan). School of Medicine

    2001-04-01

    In order to establish a treatment for intramedullary spinal cord tumors, histology, symptoms (preoperative, upon discharge from the hospital, and at the final follow-up examination), postoperative combination therapy, postoperative complications, and recurrence were assessed in patients with intramedullary spinal cord tumors treated in the author's hospital during the past 19 years. There were 26 subjects (astrocytoma in 8, ependymoma in 6, intramedullary neurinoma in 3, lipoma in 3, hemangioblastoma in 3, cavernous angioma in 1, capillary hemangioma in 1, and enterogenous cyst in 1). Surgery had been performed in 24 of them, and 7 of the tumors were completely resected, 6 were incompletely resected, and 3 were partially resected. Radiotherapy had been performed to treat 7 astrocytomas and 2 ependymomas. Kyphosis was noted as a postoperative complication in 1 patient with an astrocytoma who had received postoperative radiotherapy. Postoperative improvement was better in the patients who had the ependymomas, lipoma, and angioma, and in 1 patient with an astrocytoma. The astrocytomas were very difficult to completely remove surgically, and postoperative radiotherapy was thought to be indispensable. The ependymomas, hemangioblastomas, and angiomas could be surgically resected, but the surgeon must has to exercise sufficient care during the operation. The lipomas were also difficult to resect surgically and intratumoral decompression or decompression should be performed. For adolescents spinal deformity should be considered as one of the postoperative complications. (K.H.)

  19. Treatments of intramedullary spinal cord tumors

    Energy Technology Data Exchange (ETDEWEB)

    Ueyama, Kazumasa; Okada, Akihiro; Echigoya, Naoki; Yokoyama, Toru; Harata, Seiko [Hirosaki Univ., Aomori (Japan). School of Medicine

    2001-04-01

    In order to establish a treatment for intramedullary spinal cord tumors, histology, symptoms (preoperative, upon discharge from the hospital, and at the final follow-up examination), postoperative combination therapy, postoperative complications, and recurrence were assessed in patients with intramedullary spinal cord tumors treated in the author's hospital during the past 19 years. There were 26 subjects (astrocytoma in 8, ependymoma in 6, intramedullary neurinoma in 3, lipoma in 3, hemangioblastoma in 3, cavernous angioma in 1, capillary hemangioma in 1, and enterogenous cyst in 1). Surgery had been performed in 24 of them, and 7 of the tumors were completely resected, 6 were incompletely resected, and 3 were partially resected. Radiotherapy had been performed to treat 7 astrocytomas and 2 ependymomas. Kyphosis was noted as a postoperative complication in 1 patient with an astrocytoma who had received postoperative radiotherapy. Postoperative improvement was better in the patients who had the ependymomas, lipoma, and angioma, and in 1 patient with an astrocytoma. The astrocytomas were very difficult to completely remove surgically, and postoperative radiotherapy was thought to be indispensable. The ependymomas, hemangioblastomas, and angiomas could be surgically resected, but the surgeon must has to exercise sufficient care during the operation. The lipomas were also difficult to resect surgically and intratumoral decompression or decompression should be performed. For adolescents spinal deformity should be considered as one of the postoperative complications. (K.H.)

  20. Flexible intramedullary nailing for femoral diaphyseal fractures in children

    Directory of Open Access Journals (Sweden)

    Rojan Tamrakar

    2017-12-01

    Full Text Available Background & Objectives: Although various treatment options are available for the treatment of femoral diaphyesal fractures in children, the titanium flexible nailing has gained popularity because it is safe, easy procedure with rapid recovery and high success rate. The aim of this study was to evaluate the outcome of titanium elastic nails in treating paediatric femoral diaphyesal fractures at Patan Hospital.Materials & Methods: There were 35 cases which were all fixed with titanium flexible intramedullary nail under image intensifier at the Patan hospital from January 2013 and December 2015. Patients were evaluated in follow-ups to observe the alignment of fracture, infection, delayed union, nonunion, limb length discrepancy, implant failure, range of movement of hip and knee joints, and time to unite the fracture. The final results were evaluated using criteria of titanium elastic nail (TEN outcome score described by Flynn et al.Results: The mean age of the patients was 8.51 years. Among 35 patients (22 boys and 13 girls, there were 19 mid-shaft fractures, nine proximal third fractures and seven distal third fractures. Fracture patterns were transverse (22, oblique (10, spiral (2, and comminuted (2. The mean time for fracture union was 8.17 weeks radiologically whereas 9.83 weeks clinically. According to TEN outcome score, excellent and good results were in 28 cases (80% and seven cases (20% respectively.Conclusion: Flexible titanium nailing is a safe and satisfactory treatment for diaphyseal femoral fractures in children, because it provides rapid recovery, short rehabilitation and immobilization as well as very high union rate with few complications.

  1. Dosimetry during intramedullary nailing of the tibia.

    Science.gov (United States)

    Kirousis, George; Delis, Harry; Megas, Panagiotis; Lambiris, Elias; Panayiotakis, George

    2009-10-01

    Intramedullary nailing under fluoroscopic guidance is a common operation. We studied the intraoperative radiation dose received by both the patient and the personnel. 25 intramedullary nailing procedures of the tibia were studied. All patients suffered from tibial fractures and were treated using the Grosse-Kempf intramedullary nail, with free-hand technique for fixation of the distal screws, under fluoroscopic guidance. The exposure, at selected positions, was recorded using an ion chamber, while the dose area product (DAP) was measured with a DAP meter, attached to the tube head. Thermoluminescent dosimeters (TLDs) were used to derive the occupational dose to the personnel, and also to monitor the surface dose on the gonads of some of the patients. The mean operation time was 101 (48-240) min, with a mean fluoroscopic time of 72 seconds and a mean DAP value of 75 cGy x cm(2). The surface dose to the gonads of the patients was less than 8.8 mGy during any procedure, and thus cannot be considered to be a contraindication for the use of this technique. Occupational dose differed substantially between members of the operating personnel, the maximum dose recorded being to the operator of the fluoroscopic equipment (0.11 mSv). Our findings underscore the care required by the primary operator not to exceed the dose constraint of 10 mSv per year. The rest of the operating personnel, although they do not receive very high doses, should focus on the dose optimization of the technique.

  2. Intramedullary tuberculomas: MR findings in seven patients

    International Nuclear Information System (INIS)

    Parmar, H.; Varma, R.; Shah, J.; Patkar, D.

    2000-01-01

    To describe the MR findings in intramedullary tuberculomas and to discuss the usefulness of MR in the management of this pathology. Material and Methods: A retrospective study of 7 patients from 21 to 60 years of age with clinical and radiological evidence of intramedullary tuberculomas was undertaken. Both T1- and T2-weighted images (WI) were obtained along with postcontrast T1WI. Signal intensities (SIs) of the granulomas were compared with SIs of the normal spinal cord. Results: Six patients showed focus of tuberculosis elsewhere in the body. Six out of 7 showed fusiform swelling of the cord. Ill-defined iso-intensity (in 4 patients) to hyperintensity (in 3 patients) was seen at the site of granuloma on T1WI. On T2WI, 2 patients revealed a hypointense area (with disc enhancement). An iso-hypointense rim was seen surrounding a hyperintense centre in 5 patients (with rim enhancement). Adjacent oedema was seen in all patients. In 2 patients meningeal enhancement was also seen. In 2 patients the histopathology following surgical biopsy confirmed the diagnosis. In the remaining 5 patients, another known focus of tuberculosis elsewhere in the body and a marked response to antitubercular treatment was considered confirmatory for tuberculomas. Conclusion: Hypo- or iso-intensity on T2WI within the spinal cord with surrounding hyperintense oedema is suggestive of intramedullary tuberculomas. Central hyperintensities are also detected at times due to a variable amount of caseous necrosis with liquefaction. On T1WI, fusiform swelling of the cord is seen along with iso- to hyperintense foci, surrounded by hypointense oedema of the cord. Such findings should prompt a contrast-enhanced study, which may show single or conglomerate disc- or ring-enhancing lesions. MR thus plays an important role not only in detection and diagnosis, but also in deciding the treatment options and in the follow-up of those patients

  3. Comparison and analysis of reoperations in two different treatment protocols for trochanteric hip fractures - postoperative technical complications with dynamic hip screw, intramedullary nail and Medoff sliding plate.

    Science.gov (United States)

    Paulsson, Johnny; Stig, Josefine Corin; Olsson, Ola

    2017-08-24

    In treatment of unstable trochanteric fractures dynamic hip screw and Medoff sliding plate devices are designed to allow secondary fracture impaction, whereas intramedullary nails aim to maintain fracture alignment. Different treatment protocols are used by two similar Swedish regional emergency care hospitals. Dynamic hip screw is used for fractures considered as stable within the respective treatment protocol, whereas one treatment protocol (Medoff sliding plate/dynamic hip screw) uses biaxial Medoff sliding plate for unstable pertrochanteric fractures and uniaxial Medoff sliding plate for subtrochanteric fractures, the second (intramedullary nail/dynamic hip screw) uses intramedullary nail for subtrochanteric fractures and for pertrochanteric fractures with intertrochanteric comminution or subtrochanteric extension. All orthopedic surgeries are registered in a regional database. All consecutive trochanteric fracture operations during 2011-2012 (n = 856) and subsequent technical reoperations (n = 40) were derived from the database. Reoperations were analysed and classified into the categories adjustment (percutaneous removal of the locking screw of the Medoff sliding plate or the intramedullary nail, followed by fracture healing) or minor, intermediate (reosteosynthesis) or major (hip joint replacement, Girdlestone or persistent nonunion) technical complications. The relative risk of intermediate or major technical complications was 4.2 (1.2-14) times higher in unstable pertrochanteric fractures and 4.6 (1.1-19) times higher in subtrochanteric fractures with treatment protocol: intramedullary nail/dynamic hip screw, compared to treatment protocol: Medoff sliding plate/dynamic hip screw. Overall rates of intermediate and major technical complications in unstable pertrochanteric and subtrochanteric fractures were with biaxial Medoff sliding plate 0.68%, with uniaxial Medoff sliding plate 1.4%, with dynamic hip screw 3.4% and with intramedullary nail 7.2%. The

  4. Primary Intradural Hemangiopericytoma With Intramedullary Invasion

    Directory of Open Access Journals (Sweden)

    Chiang-Wei Chou

    2009-10-01

    Full Text Available Hemangiopericytoma (HPC is a rare tumor of the central nervous system and is usually found intracranially. Intraspinal HPCs are very rare and mostly involve the extradural bony structures. Primary intradural HPC has only been reported in 10 cases, all of which occurred in the extramedullary region. Intramedullary invasion has never been reported. Here, we describe a case of primary intradural HPC of the thoracic spine that presented initially with paresthesia and paraplegia of both legs. Magnetic resonance imaging of the thoracic spine showed an intradural dumbbell-shaped tumor at the T10 level. The initial impression was neurogenic tumor, meningioma, or metastasis. During operation, the tumor was found to have obvious intramedullary invasion. Gross-total removal was done, and the patient's neurological function improved; there was no recurrence at the 3-year follow-up. There is no consensus as to what constitutes the optimal treatment of HPC, but most neurosurgeons will advocate gross-total resection. A comparative analysis between intradural and extradural HPCs showed a higher chance of gross-total resection for intradural HPCs, while the recurrence rates showed no difference. The role of adjuvant radiotherapy remains uncertain. Due to the high risk of recurrence and metastasis of HPCs, close follow-up for a long period is mandatory. [J Chin Med Assoc 2009;72(10:536–541

  5. An evaluation of flexible intramedullary nail fixation in femoral shaft fractures in paediatric age group.

    Science.gov (United States)

    Kumar, Sanjay; Roy, Sandip Kumar; Jha, Amrish Kumar; Chatterjee, Debdutta; Banerjee, Debabrata; Garg, Anant Kumar

    2011-06-01

    Sixty-two femoral shaft fractures in 60 patients treated by elastic intramedullary nailing with mean age of the patients being 9.2 years (range 5 years to 12 years) and average follow-up of 15 months (range 7 months to 60 months) are evaluated. Twenty-eight fractures were fixed with titanium elastic nail while 34 fractures were fixed with Enders nail. There were 40 midshaft fractures, 18 proximal femoral and 4 were fractures of distal third. Fracture patterns were transverse in 35, short oblique in 14 cases and 13 were spiral fractures. Mean age of union in this series was 17 weeks (range 12 weeks to 28 weeks). Ten cases had complications, 5 had nail tip irritation, 3 varus or valgus malalignment and 2 had delayed union. In this series, we did not have any non-union, refracture, limb length discrepancy or any major infection. The result demonstrates 100% union rate irrespective of the age, weight and height of the patient. Regardless of the site of fracture and their pattern, it united every time with elastic nail fixation. We did not find and mismatch in the results of fractures stabilised with titanium elastic nail with that of elastic stainless steel nail.

  6. An arachnoid cyst presenting as an intramedullary tumour

    NARCIS (Netherlands)

    Willems, P. W.; van den Bergh, W. M.; Vandertop, W. P.

    2000-01-01

    A case of thoracic intradural extramedullary arachnoid cyst is presented in which an intramedullary low grade glioma was suspected preoperatively. The cyst was widely fenestrated and postoperatively, the patient experienced considerable improvement in her symptoms. As postoperative MRI studies also

  7. Combined spinal intramedullary arteriovenous malformation and lipomyelomeningocele

    Energy Technology Data Exchange (ETDEWEB)

    Weon, Y.C.; Roh, H.G.; Byun, H.S. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology, Seoul (Korea); Chung, J.I. [Medimoa Hospital, Department of Radiology, Seoul (Korea); Eoh, W. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea)

    2005-10-01

    Combined spinal arteriovenous malformation and lipomyelomeningocele are extremely rare. We present a rare combined case of a lipomyelomeningocele with an intramedullary arteriovenous malformation (AVM) occurred at the L3-L4 level in a 30-year-old man who suffered from low back pain radiating to the lower extremities, dysuria, and frequency for 5 years. The MR studies showed an intradural mass with high-signal intensity on both T1-weighted and T2-weighted images, intermingled with multiple signal-void structures. The mass extended extradurally toward a subcutaneously forming fatty mass on the patient's back. Spinal angiography showed an AVM supplied by the radiculopial branches of the lumbar arteries and drained by tortuous, dilated, perimedullary veins. Endovascular embolization and surgical resection were performed. (orig.)

  8. Recurrent intramedullary epidermoid cyst of conus medullaris.

    LENUS (Irish Health Repository)

    Fleming, Christina

    2011-01-01

    Spinal intramedullary epidermoid cyst is a rare condition. Recurrent epidermoid cyst in the spine cord is known to occur. The authors describe a case of recurrent conus medullaris epidermoid cyst in a 24-year-old female. She initially presented at 7 years of age with bladder disturbance in the form of diurnal enuresis and recurrent urinary tract infection. MRI lumbar spine revealed a 4 cm conus medullaris epidermoid cyst. Since the initial presentation, the cyst had recurred seven times in the same location and she underwent surgical intervention in the form of exploration and debulking. This benign condition, owing to its anatomical location, has posed a surgical and overall management challenge. This occurrence is better managed in a tertiary-care centre requiring multi-disciplinary treatment approach.

  9. Intramedullary disorders diagnosed by MRI. Clinical course in 23 cases

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Kensei; Ohashi, Teruaki; Ishibashi, Kazumasa; Hirohashi, Akiyuki; Sato, Kimiaki [Kurume Univ., Fukuoka (Japan). School of Medicine

    1996-09-01

    We report the clinical course of 23 cases with intramedullary disorders diagnosed by MRI. Spinal vascular disease was the most common, and occurred in 11 cases, intramedullary tumor occurred in 6, and multiple sclerosis, myelitis, spinal edema each in 2. The characteristic MRI findings of the intramedullary disorders were spinal cord swelling on T1 weighted image and changes in the intensity on the T2 weighted image. Surgical treatment was performed in 5 of the 11 with spinal vascular disease and in 6 with an intra-medullary tumor. One patient with AV malformation underwent embolization of the spinal artery. The other 11 received conservative treatment. The period of follow-up ranged from 6 months to 9 years after onset. Complete recovery from symptoms was achieved in only 2 patients, some recovery was achieved in 8, no change in 10, and deterioration occurred in 3. In conclusion, it has become easy to diagnose intramedullary disorders by utilizing MRI. However, an accurate qualitative diagnosis is difficult except for spinal vascular disease. Complete recovery from the symptoms of intramedullary disorders remains difficult to achieve by available treatments. (author)

  10. Intramedullary disorders diagnosed by MRI. Clinical course in 23 cases

    International Nuclear Information System (INIS)

    Nagata, Kensei; Ohashi, Teruaki; Ishibashi, Kazumasa; Hirohashi, Akiyuki; Sato, Kimiaki

    1996-01-01

    We report the clinical course of 23 cases with intramedullary disorders diagnosed by MRI. Spinal vascular disease was the most common, and occurred in 11 cases, intramedullary tumor occurred in 6, and multiple sclerosis, myelitis, spinal edema each in 2. The characteristic MRI findings of the intramedullary disorders were spinal cord swelling on T1 weighted image and changes in the intensity on the T2 weighted image. Surgical treatment was performed in 5 of the 11 with spinal vascular disease and in 6 with an intra-medullary tumor. One patient with AV malformation underwent embolization of the spinal artery. The other 11 received conservative treatment. The period of follow-up ranged from 6 months to 9 years after onset. Complete recovery from symptoms was achieved in only 2 patients, some recovery was achieved in 8, no change in 10, and deterioration occurred in 3. In conclusion, it has become easy to diagnose intramedullary disorders by utilizing MRI. However, an accurate qualitative diagnosis is difficult except for spinal vascular disease. Complete recovery from the symptoms of intramedullary disorders remains difficult to achieve by available treatments. (author)

  11. [Intramedullary stabilisation of displaced midshaft clavicular fractures: does the fracture pattern (simple vs. complex) influence the anatomic and functional result].

    Science.gov (United States)

    Langenhan, R; Reimers, N; Probst, A

    2014-12-01

    Displaced midshaft clavicular fractures are often treated operatively. The most common way of treatment is plating. Elastic stable intramedullary nailing (ESIN) is an alternative, but seldom used. Studies showed comparable or even better results for intramedullary nailing than for plating in simple 2- or 3-fragment midshaft fractures. The indication of ESIN for multifragmentary clavicular fractures is discussed critically in the literature because of reduced primary stability and danger of secondary shortening. Until now only few studies report functional results after fracture healing depending on the fracture type. To the best of our knowledge there is no study showing significantly worse functional scores for ESIN in complex displaced midshaft fractures. The objective of this study was to examine anatomic and functional results of simple (2 or 3 fragments, OTA type 15B1 and 15B2) and complex (multifragmentary, OTA type 15B3) displaced midshaft clavicula fractures after internal fixation. Between 2009 and 2012, 40 patients (female/male 10/30; mean age 33 [16-60] years) with closed displaced midshaft clavicular fractures were treated by open reduction and ESIN (Titanium Elastic Nail [TEN], Synthes, Umkirch, Germany). Thirty-seven patients were retrospectively analysed after a mean of 27 (12-43) months. Twenty patients (group A) had simple fractures (OTA type 15B1 and 15B2), 17 patients (group B) had complex fractures (OTA type 15B3). All shoulder joints were postoperatively treated functionally for six weeks without weight limited to 90° abduction/flexion. Both groups were comparable in gender, age, body mass index, months until metal removal, number of physiotherapy sessions and time until follow-up examination. Joint function (neutral zero method) and strength (standing patient with arm in 90° abduction, holding 1-12 kg for 5 sec) in both shoulders were documented. The distance between the centre of the jugulum and the lateral acromial border was measured for

  12. The stability of a hip fracture determines the fatigue of an intramedullary nail.

    Science.gov (United States)

    Eberle, S; Bauer, C; Gerber, C; von Oldenburg, G; Augat, P

    2010-01-01

    The purpose of this study was to address the question of how the stability of a proximal hip fracture determines the fatigue and failure mechanism of an intramedullary implant. To answer this question, mechanical experiments and finite element simulations with two different loading scenarios were conducted. The two load scenarios differed in the mechanical support of the fracture by an artificial bone sleeve, representing the femoral head and neck. The experiments confirmed that an intramedullary nail fails at a lower load in an unstable fracture situation in the proximal femur than in a stable fracture. The nails with an unstable support failed at a load 28 per cent lower than the nails with a stable support by the femoral neck. Hence, the mechanical support of a fracture is crucial to the fatigue failure of an implant. The simulation showed why the fatigue fracture of the nail starts at the aperture of the lag screw. It is the location of the highest von Mises stress, which is the failure criterion for ductile materials.

  13. Temperature coefficient of elastic constants of SiO2 over-layer on LiNbO3 for a temperature stable SAW device

    International Nuclear Information System (INIS)

    Tomar, Monika; Gupta, Vinay; Sreenivas, K

    2003-01-01

    The influence of sputtered SiO 2 over-layer on the SAW propagation characteristics of a 128 deg. rotated Y-cut X-propagating lithium niobate SAW filter has been studied. Experimentally measured SAW phase velocity and temperature coefficient of delay (TCD), with varying SiO 2 over-layer thickness, show a significant deviation from the theoretically calculated values using the bulk material parameters of SiO 2 . The observed deviation is attributed to the differences in the material parameters (density, elastic and dielectric constants and their temperature coefficient) of the deposited SiO 2 over-layer. The density and the dielectric constant of the deposited SiO 2 layer were determined separately, and the elastic constants and their temperature coefficients were estimated by fitting the experimental velocity and TCD data, respectively. The deviation in the dielectric constant and the density in comparison to the bulk was insignificant, and the estimated values of the elastic constants (C 11 = 0.75x10 11 N m -2 and C 44 0.225x10 11 N m -2 ) were found to be lower, and the respective temperature coefficients (5.0x10 -4 deg C -1 and 2.0x10 -4 deg C -1 ) were high in comparison to the bulk material parameters

  14. Temperature coefficient of elastic constants of SiO{sub 2} over-layer on LiNbO{sub 3} for a temperature stable SAW device

    Energy Technology Data Exchange (ETDEWEB)

    Tomar, Monika; Gupta, Vinay; Sreenivas, K [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

    2003-08-07

    The influence of sputtered SiO{sub 2} over-layer on the SAW propagation characteristics of a 128 deg. rotated Y-cut X-propagating lithium niobate SAW filter has been studied. Experimentally measured SAW phase velocity and temperature coefficient of delay (TCD), with varying SiO{sub 2} over-layer thickness, show a significant deviation from the theoretically calculated values using the bulk material parameters of SiO{sub 2}. The observed deviation is attributed to the differences in the material parameters (density, elastic and dielectric constants and their temperature coefficient) of the deposited SiO{sub 2} over-layer. The density and the dielectric constant of the deposited SiO{sub 2} layer were determined separately, and the elastic constants and their temperature coefficients were estimated by fitting the experimental velocity and TCD data, respectively. The deviation in the dielectric constant and the density in comparison to the bulk was insignificant, and the estimated values of the elastic constants (C{sub 11} = 0.75x10{sup 11} N m{sup -2} and C{sub 44} 0.225x10{sup 11} N m{sup -2}) were found to be lower, and the respective temperature coefficients (5.0x10{sup -4} deg C{sup -1} and 2.0x10{sup -4} deg C{sup -1}) were high in comparison to the bulk material parameters.

  15. 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.

  16. [Clinical application of blocking screws and rooting technique in the treatment of distal tibial fracture with interlocking intramedullary nail].

    Science.gov (United States)

    Zhu, Hai-Bing; Wu, Li-Guo; Fang, Zhi-Song; Luo, Cong-Feng; Wang, Qing-Feng; Ma, Yi-Ping; Gao, Hong; Fu, Guo-Hai; Hu, Cheng-Ting

    2012-07-01

    To introduce the clinical method of blocking screws and rooting technique in the treatment of distal tibial fracture with interlocking intramedullary nails. From June 2006 to March 2011, 26 patients with distal tibial fracture were treated with interlocking intramedullary nails using blocking screws and rooting technique, included 18 males and 8 females with an average age of 46.2 years old ranging from 24 to 64 years. According to AO classification: 10 cases of type A1, 4 cases of type A2, 8 cases of type B1, 4 cases of type B2. The average distance of the fractures end to the ankle joint was 85 mm ranging from 55 to 125 mm, the mean time between injured and operation was 4.5 days. The patients were evaluated with pain, range of motion, walking. All cases were followed-up for 6 to 22 months (averaged 15 months). According to Iowa ankle joint grading system,the score was improved from preoperative (66.8 +/- 8.2) to postoperative (94.6 +/- 4.8). All fractures had united, and got satisfactory reduction and stable fixation with no complications had happen such as breakage of screw. Fixation with interlocking intramedullary nail using blocking screws and rooting technique in treating distal tibial fracture, is a safe and effective technique for the improvement of stability.

  17. Safe surgical technique: intramedullary nail fixation of tibial shaft fractures.

    Science.gov (United States)

    Zelle, Boris A; Boni, Guilherme

    2015-01-01

    Statically locked, reamed intramedullary nailing remains the standard treatment for displaced tibial shaft fractures. Establishing an appropriate starting point is a crucial part of the surgical procedure. Recently, suprapatellar nailing in the semi-extended position has been suggested as a safe and effective surgical technique. Numerous reduction techiques are available to achieve an anatomic fracture alignment and the treating surgeon should be familiar with these maneuvers. Open reduction techniques should be considered if anatomic fracture alignment cannot be achieved by closed means. Favorable union rates above 90 % can be achieved by both reamed and unreamed intramedullary nailing. Despite favorable union rates, patients continue to have functional long-term impairments. In particular, anterior knee pain remains a common complaint following intramedullary tibial nailing. Malrotation remains a commonly reported complication after tibial nailing. The effect of postoperative tibial malalignment on the clinical and radiographic outcome requires further investigation.

  18. Intramedullary cavernous hemangiomas, magnetic resonance studies in four patients

    International Nuclear Information System (INIS)

    Barrena, M.R.; Guelbenzu, S.; Garcia, S.; Bertrol, V.

    1998-01-01

    Intramedullary cavernous hemangiomas are vascular malformations that can be located throughout the entire central nervous system. They are more frequently found in brain than in spinal cord, where it is only possible to diagnose them by magnetic resonance (RM): We present four cases of intramedullary spinal cord cavernoma, three of which were located in the thoracic spine and one in cervical spine. Computed tomography was ineffective in their diagnosis. However, MR disclosed there presence of well-defined tumors producing a thickening of the spinal cord. The signal was heterogeneous in both T1 and T2-weighted images. There were low signal areas due to the presence of calcium and hemosiderin and high intensity signals provoked by methemoglobin within the lesions, which were scarcely enhanced by intravenous gadolinium administration. One of the lesions presented in the form of a large intramedullary hematoma. (Author) 8 refs

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

    Science.gov (United States)

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

    1998-02-01

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

  20. Skeletal traction and intramedullary nailing cost-effectiveness

    African Journals Online (AJOL)

    In the operative group 24 patients had union with one delayed union while in the traction group 12 patients had union, 9 with mal union and 4 delayed union. Conclusion: Intramedullary nailing is more cost-effective than skeletal traction. It met the dominant strategy, because it was significantly less costly than skeletal ...

  1. Snapping scapular syndrome secondary to rib intramedullary fixation device

    Directory of Open Access Journals (Sweden)

    Ezequiel E. Zaidenberg

    2015-01-01

    Conclusion: Surgeons should pay attention to any protrusion of intramedullary rib implants, especially in the evaluation of routine X-rays following surgical treatment. We should be aware of the possibility of this rare cause of snapping scapula syndrome to avoid delayed diagnosis and consider removing the implant will resolve the pain.

  2. Clinical Outcomes after Open Locked Intramedullary Nailing of ...

    African Journals Online (AJOL)

    2017-12-05

    Dec 5, 2017 ... joint stiffness due to prolonged immobilization.[8,9] Open reduction and internal fixation have reduced some of these complications by enabling early mobilization of the patient after surgery. The gold standard for treating closed femoral shaft fractures currently is closed locked intramedullary nailing.[10-13] ...

  3. Intramedullary cavernous haemangioma of spinal cord: A case ...

    African Journals Online (AJOL)

    Thoracic myelography done showed bilateral symmetrical funnelling of the contrast at the level of T5 with widening of the spinal cord, which are typical characteristics of an intramedullary mass of spinal cord. T2-T6 Laminectomy was done. Near total excision of a 4 by 2.5 cm intradural, intramedulary bluish black, necrotic, ...

  4. Nonunions of the distal tibia treated by reamed intramedullary nailing

    NARCIS (Netherlands)

    Richmond, Jeffrey; Colleran, Kevin; Borens, Olivier; Kloen, Peter; Helfet, David L.

    2004-01-01

    The purpose of this study is to determine the efficacy of reamed intramedullary nailing in the treatment of nonunions of the distal one-fourth of the tibia. Nonunions of the distal tibia are particularly difficult to treat given the short distal segment, the proximity to the ankle joint, and the

  5. Elastic properties

    International Nuclear Information System (INIS)

    Ledbetter, H.M.

    1983-01-01

    This chapter investigates the following five aspects of engineering-material solid-state elastic constants: general properties, interrelationships, relationships to other physical properties, changes during cooling from ambient to near-zero temperature, and near-zero-temperature behavior. Topics considered include compressibility, bulk modulus, Young's modulus, shear modulus, Poisson's ratio, Hooke's law, elastic-constant measuring methods, thermodynamic potentials, higher-order energy terms, specific heat, thermal expansivity, magnetic materials, structural phase transitions, polymers, composites, textured aggregates, and other-phenomena correlations. Some of the conclusions concerning polycrystalline elastic properties and their temperature dependence are: elastic constants are physical, not mechanical, properties which relate thermodynamically to other physical properties such as specific heat and thermal expansivity; elastic constants at low temperatures are nearly temperature independent, as required by the third law of thermodynamics; and elastic constants can be used to study directional properties of materials, such as textured aggregates and composites

  6. Primary unreamed intramedullary locked nailing in open fractures of tibia

    Directory of Open Access Journals (Sweden)

    Jain Vineet

    2005-01-01

    Full Text Available Background: Fractures of tibia are among the commonest fractures sustained in road traffic accidents. They are frequently open and contaminated. Unreamed nails are considered superior to external fixator in the management of open fractures of tibia. Method: Forty patients with open fractures of tibia, grade I, II, IIIa, IIIb were included in the study. They were managed by primary unreamed intramedullary nailing with adequate soft tissue management. Results: Functional results were excellent in 26 cases, good in 10 cases and fair in 4 cases. Four cases had delayed union. Average time of union was 16.9 weeks. Conclusion: Primary unreamed intramedullary nailing offers advantage of rigid fixation, low incidence of infection, non-union, good functional results and early return to work. An adequate soft tissue management is mandatory in treatment of these fractures.

  7. Total excision of intramedullary epidermoid cyst in one case

    Directory of Open Access Journals (Sweden)

    PU Ke

    2013-12-01

    Full Text Available Clinical experience of total excision in a 14-year-old female with intramedullary epidermoid cyst was reported. The patient with L3-4 intramedullary epidermoid cyst underwent total excision through posterior median approach under microscopy. The patient was admitted for progressive strephexopodia and urinary and fecal incontinence. Preoperative imaging examination showed scoliosis, incontionous L4-S1 and abnormal signal of L3-4. Total excision and spinal remodeling were performed under intraoperative neurophysiological monitoning. Epidermoid cyst and its membrane were totally removed without aseptic meningitis after surgery, and the neurologic symptoms of the patient were gradually improved. Completely removing the membrane of epidermoid cyst is the key point to prevent recurrence and aseptic meningitis postoperatively. Dissection should be strictly in accordance with the boundaries of the membrane and the spinal cord, in order to avoid spinal cord injury.

  8. Use of Titanium Elastic Nails in the Adult Diaphyseal Humerus Fractures

    Directory of Open Access Journals (Sweden)

    Upadhyay AS

    2017-07-01

    Full Text Available INTRODUCTION: Humerus shaft fractures in adults can be managed conservatively with functional braces or operatively with plate osteosynthesis or with intramedullary nailing. Conventionally humerus intramedullary nailing is done either using humerus interlocking nails or Enders nails. In this study we analyse the outcome of humerus shaft fractures (upper and middle third managed with closed ante- grade intramedullary titanium elastic nailing in terms of union rates, union time, functional results and complications. MATERIALS AND METHODS: A retrospective analysis of 25 patients treated with ante-grade intramedullary titanium elastic nailing was done during the period of August 2014 to June 2016 at our tertiary care centre. Skeletally mature patients with closed and acute fractures of the upper and middle shaft humerus of both sexes were included in the study. RESULTS: Twenty-five (100% fractures united with an average consolidation time of 14.98 weeks (10-32 weeks, and no fractures ended in non-union. Nail impingement was seen in two (8%, shoulder stiffness in one (4%. Functional results were excellent in 22 (88%, moderate in two (8% and poor in one (4%. There were 17 males and eight females with an average age of 39.08 years (range: 18-65 years. The average duration of hospital stay was 3.84±2.30 days. CONCLUSION: Closed ante-grade intramedullary titanium elastic nailing offers a safe and reliable method of fixing fractures of upper humeral shaft in adults. This method provides early fracture union, high union rates and less complications, in addition to early rehabilitation and reduces the hospital stay.

  9. MR imaging of intramedullary ischemia due to cervical spondylosis

    International Nuclear Information System (INIS)

    Dooms, G.; Mathurin, P.; Cornelis, G.; Hulcelle, P.

    1988-01-01

    A retrospective study was performed to assess the value of MR imaging for detecting intramedullary ischemia due to cervical spondylosis and to assess its clinical significance. One hundred consecutive unselected patients (70 men and 30 women, mean age = 62 years) were included in the study. All patients were treated surgically, either by anterior diskectomy and corporectomy or by posterior laminectomy. Clinical follow-up to 2 years was available for every patient. MR imaging was performed with a superconducting magnet (Philips Gyroscan S15) operating at 1.5T Sagittal T1-weighted (repetition time [TR] = 0.45 sec and echo time [TE] = 30 msec) and cardiac-gated T2-weighted (TR>1.2 sec and multiples TE of 50, 100 and 200 msc) imaging was performed in every patient. Cervical spondylosis was exquisitely demonstrated on MR images in every patient. With the sagittal plane, full extent and the degree of canalar stenosis were easily appreciated on T2-weighted images. A hyperintense intramedullary lesion was detected preoperatively in 24 of the patients and corresponded presumably to ischemic, edematous, and/or necrotic damage to the cord. It was usually located at the level or just below the level where the most severe canalar stenosis was demonstrated; it was identified only on T2-weighted images. In a comparison of the clinical outcome of the patients after surgery, there was a striking difference between the group of patients without and that with intramedullary lesions. In the first group, the relief of symptoms after surgery was partial or complete. In the other group, the clinical outcome was poor and symptom relief nearly absent. In conclusion, MR imaging is an exquisite modality for demonstrating necrotic intramedullary changes due to cervical spondylosis and thus may aid in determining the prognosis for surgery and clinical outcome of the patients

  10. Outcome of intramedullary interlocking SIGN nail in tibial diaphyseal fracture

    International Nuclear Information System (INIS)

    Khan, I.; Javed, S.; Khan, G.N.; Aziz, A.

    2013-01-01

    Objective: To determine the outcome of intramedullary interlocking surgical implant generation network (SIGN) nail in diaphyseal tibial fractures in terms of union and failure of implant (breakage of nail or interlocking screws). Study Design: Case series. Place and Duration of Study: Orthopaedics and Spinal Surgery, Ghurki Trust Teaching Hospital, Lahore Medical and Dental College, Lahore, from September 2008 to August 2009. Methodology: Fifty patients aged 14 - 60 years, of either gender were included, who had closed and Gustilo type I and II open fractures reported in 2 weeks, whose closed reduction was not possible or was unsatisfactory and fracture was located 7 cm below knee joint to 7 cm above ankle joint. Fractures previously treated with external fixator, infected fractures and unfit patients were excluded. All fractures were fixed with intramedullary interlocking SIGN nail and were followed clinically and radiographically for union and for any implant failure. Results: Forty one (88%) patients had united fracture within 6 months, 5 (10%) patients had delayed union while 4 (8%) patients had non-union. Mean duration for achieving union was 163 + 30.6 days. Interlocking screws were broken in 2 patients while no nail was broken in any patient. Conclusion: Intramedullary interlocking nailing is an effective measure in treating closed and grade I and II open tibial fractures. It provides a high rate of union less complications and early return to function. (author)

  11. Tibiotalocalcaneal arthrodesis with a curved, interlocking, intramedullary nail.

    Science.gov (United States)

    Budnar, Vijaya M; Hepple, Steve; Harries, William G; Livingstone, James A; Winson, Ian

    2010-12-01

    Tibiotalocalcaneal fusion with a straight rod has a risk of damaging the lateral plantar neurovascular structures and may interfere with maintaining normal heel valgus position.We report the results of a prospective study of tibiotalocalcaneal (TTC) arthrodesis with a short, anatomically curved interlocking, intramedullary nail. Forty-five arthrodesis in 42 patients, performed between Jan 2003 and Oct 2008, were prospectively followed. The mean followup was 48 (range, 10 to 74) months. The main indications for the procedure were failed ankle arthrodesis with progressive subtalar arthritis, failed ankle arthroplasty and complex hindfoot deformity. The outcome was measured by a combination of pre and postoperative clinical examination, AOFAS hindfoot scores, SF-12 scores and radiological assessment. Union rate was 89% (40/45). Eighty-two percent (37/45) reported improvement in pain and 73% (33/45) had improved foot function. Satisfactory hindfoot alignment was achieved in 84% (38/45). Postoperatively there was a mean improvement in the AOFAS score of 37. Complications included a below knee amputation for persistent deep infection, five nonunions, and three delayed unions. Four nails, six proximal and six distal locking screws were removed for various causes. Other complications included two perioperative fractures, four superficial wound infections and one case of lateral plantar nerve irritation. With a short, anatomically curved intramedullary nail, we had a high rate of tibiotalocalcaneal fusion with minimal plantar neurovascular complications. We believe a short, curved intramedullary nail, with its more lateral entry point, helped maintain hindfoot alignment.

  12. Outcome of intramedullary interlocking SIGN nail in tibial diaphyseal fracture.

    Science.gov (United States)

    Khan, Irfanullah; Javed, Shahzad; Khan, Gauhar Nawaz; Aziz, Amer

    2013-03-01

    To determine the outcome of intramedullary interlocking surgical implant generation network (SIGN) nail in diaphyseal tibial fractures in terms of union and failure of implant (breakage of nail or interlocking screws). Case series. Orthopaedics and Spinal Surgery, Ghurki Trust Teaching Hospital, Lahore Medical and Dental College, Lahore, from September 2008 to August 2009. Fifty patients aged 14 - 60 years, of either gender were included, who had closed and Gustilo type I and II open fractures reported in 2 weeks, whose closed reduction was not possible or was unsatisfactory and fracture was located 7 cm below knee joint to 7 cm above ankle joint. Fractures previously treated with external fixator, infected fractures and unfit patients were excluded. All fractures were fixed with intramedullary interlocking SIGN nail and were followed clinically and radiographically for union and for any implant failure. Forty one (88%) patients had united fracture within 6 months, 5 (10%) patients had delayed union while 4 (8%) patients had non-union. Mean duration for achieving union was 163 + 30.6 days. Interlocking screws were broken in 2 patients while no nail was broken in any patient. Intramedullary interlocking nailing is an effective measure in treating closed and grade I and II open tibial fractures. It provides a high rate of union less complications and early return to function.

  13. Neurobrucellosis presenting as an intra-medullary spinal cord abscess

    Directory of Open Access Journals (Sweden)

    Patil Chidanand S

    2005-09-01

    Full Text Available Abstract Background Of the diverse presentation of neurobrucellosis, intra-medullary spinal cord abscess is extremely rare. Only four other cases have been reported so far. We present a case of spinal cord intra-medullary abscess due to Brucella melitensis. Case presentation A forty-year-old female presented with progressive weakness of both lower limb with urinary incontinence of 6 months duration. She was febrile. Neurological examination revealed flaccid areflexic paraplegia with T10 below sensory impairment including perianal region. An intramedullary mass was diagnosed on Magnetic Resonance Image (MRI scan extending from T12 to L2. At surgery, a large abscess was encountered at the conus medullaris, from which Brucella melitensis was grown on culture. She was started on streptomycin and doxycycline for 1 month, followed by rifampicin and doxycycline for 1 month. At 2-year follow-up, she had recovered only partially and continued to have impaired bladder function. Conclusion Neurobrucellosis, if not treated early, can result in severe neurological morbidity and sequale, which may be irreversible. Hence it is important to consider the possibility of neurobrucellosis in endemic region and treat aggressively.

  14. Long-term functional outcome following intramedullary nailing of femoral shaft fractures

    NARCIS (Netherlands)

    el Moumni, Mostafa; Voogd, Emma Heather; ten Duis, Henk Jan; Wendt, Klaus Wilhelm

    Background: The management of femoral shaft fractures using intramedullary nailing is a popular method. The purpose of this study was to evaluate the long-term functional outcome after antegrade or retrograde intramedullary nailing of traumatic femoral shaft fractures. We further determined

  15. New Technique: A Novel Femoral Derotation Osteotomy for Malrotation following Intramedullary Nailing

    Directory of Open Access Journals (Sweden)

    S. Jagernauth

    2012-01-01

    Full Text Available A 19-year-old female patient sustained a closed spiral midshaft femoral fracture and subsequently underwent femoral intramedullary nail insertion. At followup she complained of difficulty in walking and was found to have a unilateral in-toeing gait. CT imaging revealed 30 degrees of internal rotation at the fracture site, which had healed. A circumferential osteotomy was performed distal to the united fracture site using a Gigli saw with the intramedullary femoral nail in situ. The static distal interlocking screws were removed and the malrotation was corrected. Two further static distal interlocking screws were inserted to secure the intramedullary nail in position. The osteotomy went on to union and her symptoms of pain, walking difficulty, and in-toeing resolved. Our paper is the first to describe a technique for derotation osteotomy following intramedullary malreduction that leaves the intramedullary nail in situ.

  16. Carbon fiber intramedullary nails reduce artifact in postoperative advanced imaging

    International Nuclear Information System (INIS)

    Zimel, Melissa N.; Hwang, Sinchun; Riedel, Elyn R.; Healey, John H.

    2015-01-01

    This study assessed whether radiolucent carbon fiber reinforced-polyetheretherketone (CFR-PEEK) intramedullary nails decreased hardware artifact on magnetic resonance imaging (MRI) and computed tomography (CT) in vitro and in an oncologic patient population. In vitro and clinical evaluations were done. A qualitative assessment of metal artifact was performed using CFR-PEEK and titanium nail MRI phantoms. Eight patients with a femoral or tibial prophylactic CFR-PEEK nail were retrospectively identified. All patients had postoperative surveillance imaging by MRI, CT, and were followed for a median 20 months (range, 12-28 months). CFR-PEEK images were compared to images from a comparative group of patients with titanium femoral intramedullary nails who had a postoperative MRI or CT. A musculoskeletal-trained radiologist graded visualization of the cortex, corticomedullary junction, and bone-muscle interface, on T1-weighted (T1W), STIR, and contrast-enhanced T1-weighted fat-saturated (T1W FS) sequences of both groups with a five-point scale, performing independent reviews 4 months apart. Statistical analysis used the Wilcoxon rank-sum test and a weighted kappa. Substantially less MRI signal loss occurred in the CFR-PEEK phantom than in the titanium phantom simulation, particularly as the angle increased with respect to direction of the static magnetic field. CFR-PEEK nails had less MRI artifact than titanium nails on scored T1W, STIR, and contrast-enhanced T1W FS MRI sequences (p ≤ 0.03). The mean weighted kappa was 0.64, showing excellent intraobserver reliability between readings. CFR-PEEK intramedullary nail fixation is a superior alternative to minimize implant artifact on MRI or CT imaging for patients requiring long bone fixation. (orig.)

  17. Carbon fiber intramedullary nails reduce artifact in postoperative advanced imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zimel, Melissa N. [Memorial Sloan Kettering Cancer Center, Orthopaedic Surgery Service, Department of Surgery, New York, NY (United States); Hwang, Sinchun [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Riedel, Elyn R. [Memorial Sloan Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Healey, John H. [Memorial Sloan Kettering Cancer Center, Orthopaedic Surgery Service, Department of Surgery, New York, NY (United States); Weill Medical College of Cornell University, Department of Orthopaedic Surgery, New York, NY (United States)

    2015-09-15

    This study assessed whether radiolucent carbon fiber reinforced-polyetheretherketone (CFR-PEEK) intramedullary nails decreased hardware artifact on magnetic resonance imaging (MRI) and computed tomography (CT) in vitro and in an oncologic patient population. In vitro and clinical evaluations were done. A qualitative assessment of metal artifact was performed using CFR-PEEK and titanium nail MRI phantoms. Eight patients with a femoral or tibial prophylactic CFR-PEEK nail were retrospectively identified. All patients had postoperative surveillance imaging by MRI, CT, and were followed for a median 20 months (range, 12-28 months). CFR-PEEK images were compared to images from a comparative group of patients with titanium femoral intramedullary nails who had a postoperative MRI or CT. A musculoskeletal-trained radiologist graded visualization of the cortex, corticomedullary junction, and bone-muscle interface, on T1-weighted (T1W), STIR, and contrast-enhanced T1-weighted fat-saturated (T1W FS) sequences of both groups with a five-point scale, performing independent reviews 4 months apart. Statistical analysis used the Wilcoxon rank-sum test and a weighted kappa. Substantially less MRI signal loss occurred in the CFR-PEEK phantom than in the titanium phantom simulation, particularly as the angle increased with respect to direction of the static magnetic field. CFR-PEEK nails had less MRI artifact than titanium nails on scored T1W, STIR, and contrast-enhanced T1W FS MRI sequences (p ≤ 0.03). The mean weighted kappa was 0.64, showing excellent intraobserver reliability between readings. CFR-PEEK intramedullary nail fixation is a superior alternative to minimize implant artifact on MRI or CT imaging for patients requiring long bone fixation. (orig.)

  18. Strength of titanium intramedullary implant versus miniplate fixation of mandibular condyle fractures.

    Science.gov (United States)

    Frake, Paul C; Howell, Rebecca J; Joshi, Arjun S

    2012-07-01

    To test the strength of internal fixation of mandibular condyle fractures repaired with titanium miniplates versus titanium intramedullary implants. Prospective laboratory experimentation in urethane mandible models and human cadaveric mandibles. Materials testing laboratory at an academic medical center. Osteotomies of the mandibular condyle were created in 40 urethane hemimandible models and 24 human cadaveric specimens. Half of the samples in each group were repaired with traditional miniplates, and the other half were repaired with intramedullary titanium implants. Anteroposterior and mediolateral loads were applied to the samples, and the displacement was measured with reference to the applied force. Titanium intramedullary implants demonstrated statistically significant improved strength and stiffness versus miniplates in the urethane model experimental groups. Despite frequent plastic deformation and mechanical failures of the miniplates, a 1.6-mm-diameter titanium intramedullary pin did not mechanically fail in any of the cases. Intramedullary implantation failures were due to secondary fracture of the adjacent cortical bone or experimental design limitations including rotation of the smooth pin implant. Mechanical implant failures that were encountered with miniplate fixation were not seen with titanium intramedullary implants. These intramedullary implants provide stronger and more rigid fixation of mandibular condyle fractures than miniplates in this in vitro model.

  19. Intramedullary spinal cord metastasis from colonic carcinoma presenting as Brown-Sequard syndrome: a case report

    LENUS (Irish Health Repository)

    Kaballo, Mohammed A

    2011-08-02

    Abstract Introduction Intramedullary spinal cord metastasis is very rare. The majority are discovered incidentally during autopsy. Most symptomatic patients present with rapidly progressive neurological deficits and require immediate examination. Few patients demonstrate features of Brown-Séquard syndrome. Radiotherapy is the gold-standard of therapy for Intramedullary spinal cord metastasis. The overall prognosis is poor and the mortality rate is very high. We present what is, to the best of our knowledge, the first case of Intramedullary spinal cord metastasis of colorectal carcinoma presenting as Brown-Séquard syndrome. Case presentation We present the case of a 71-year-old Caucasian man with colonic adenocarcinoma who developed Intramedullary spinal cord metastasis and showed features of Brown-Séquard syndrome, which is an uncommon presentation of Intramedullary spinal cord metastasis. Conclusion This patient had an Intramedullary spinal cord metastasis, a rare form of metastatic disease, secondary to colonic carcinoma. The metastasis manifested clinically as Brown-Séquard syndrome, itself a very uncommon condition. This syndrome is rarely caused by intramedullary tumors. This unique case has particular interest in medicine, especially for the specialties of medical, surgical and radiation oncology. We hope that it will add more information to the literature about these entities.

  20. Elastic Beanstalk

    CERN Document Server

    Vliet, Jurg; Wel, Steven; Dowd, Dara

    2011-01-01

    While it's always been possible to run Java applications on Amazon EC2, Amazon's Elastic Beanstalk makes the process easier-especially if you understand how it works beneath the surface. This concise, hands-on book not only walks you through Beanstalk for deploying and managing web applications in the cloud, you'll also learn how to use this AWS tool in other phases of development. Ideal if you're a developer familiar with Java applications or AWS, Elastic Beanstalk provides step-by-step instructions and numerous code samples for building cloud applications on Beanstalk that can handle lots

  1. ROLE OF INTRAMEDULLARY NAILING IN DEFORMITY CORRECTION OF LONG BONES

    Directory of Open Access Journals (Sweden)

    Anne

    2016-03-01

    Full Text Available INTRODUCTION Correction of multi-apical long bone deformities in lower limbs is a challenging task. Correction of these deformities with Ilizarov–type external fixators, treating one segment at a time increases the total time of correction and decreases the patients’ compliance with considerable discomfort. Hence we preferred intramedullary nail devices which combines accuracy, minimal invasiveness, with patient compliance and with excellent functional outcome. Temporary external fixator used per-operatively in some cases to retain the correction till the insertion of the nail. Eight patients in the age group of 12-35 yrs. presented to us over the last 1 year with multi-apical lower limb deformities. The radiological parameters described by Paley et al 1 were used to assess the pre and post–operative radiographs. With the help of anatomical axes the CORA was identified. Percutaneous osteotomy and stabilization with intramedullary nail was done to correct the deformity. 13 Femora and 7 Tibiae were subjected to correction by this technique and followed up over a period of 1 year (Nov-2014 to Nov-2015 at MIMS Vizianagaram hospital.

  2. Early effect of Ti-24Nb-4Zr-7.9Sn intramedullary nails on fractured bone

    International Nuclear Information System (INIS)

    Guo, Z.; Fu, J.; Zhang, Y.Q.; Hu, Y.Y.; Wu, Z.G.; Shi, L.; Sha, M.; Li, S.J.; Hao, Y.L.; Yang, R.

    2009-01-01

    A multifunctional titanium Ti-24Nb-4Zr-7.9Sn alloy (abbreviated as Ti2448) with ultra-low elastic modulus and high strength has been developed recently for potential biomedical applications. In this study, the bone healing and stability of implants in a rabbit tibial fracture model were investigated using intramedullary nails made of both the Ti2448 and Ti-6Al-4V ELI alloys. X-ray radiographic analysis showed that the volume fractions of new calluses formed around the fractured tibia increased with implantation times up to 4 weeks in both groups but no obvious difference was found between the alloys at the same time point. The micro-CT analysis revealed that, in the distal end of the tibia, there were many new calluses around nails made of the Ti2448 alloy that were confirmed by histological observations. The above analysis was consistent with tensile testing results performed 4 weeks after implantation. The mean maximum tensile force to failure of the newly formed calluses was similar between both groups whereas the mean maximum pull-out forces of the implanted nails were larger in the group of the Ti2448 alloy. Four weeks after fixation, no obvious difference in the degree of fracture healing was found between both groups. These results suggested that, in the early stage of fixation, the nails with ultra-low elastic modulus improved the new bone formation in the marrow cavity.

  3. Minimally invasive treatment of trochanteric fractures with intramedullary nails. Technique and results.

    Science.gov (United States)

    Todor, Adrian; Pojar, Adina; Lucaciu, Dan

    2013-01-01

    The aim of the study was to evaluate the results of minimally invasive treatment of trochanteric fractures with the use of intramedullary nails. From September 2010 to September 2012 we treated 21 patients with pertrochanteric fractures by a minimally invasive technique using the Gamma 3 (Stryker, Howmedica) nail. There were 13 females and 8 men with a mean age of 74.1 years, ranging from 58 to 88 years. Fractures were classified as being stable (AO type 31-A1) in 5 cases and unstable (AO type 31-A2 and A3) in the rest of 16 cases. Patients were reviewed at 6 weeks and 3 months postoperatively. Mean surgery time was 46.8 minutes and mean hospital stay was 14.9 days. No patients required blood transfusions. During the hospital stay all the patients were mobilized with weight bearing as tolerated. All patients were available for review at 6 weeks, and 2 were lost to the 3 months follow up. 16 patients regained the previous level of activity. This minimally invasive technique using a gamma nail device for pertrochanteric fractures gives reliable good results with excellent preservation of hip function.

  4. Articular cartilage damage with intramedullary lesion (bone bruise) in anterior cruciate ligament rupture

    International Nuclear Information System (INIS)

    Ide, Shuya; Ohdera, Toshihiro; Tokunaga, Masami; Hiroshima, Shiro; Yoshimoto, Eiji

    2002-01-01

    We evaluated the relationship between the intramedullary lesion on MRI and cartilage damage in patients associated with acute anterior cruciate ligament (ACL) rupture. Thirty-two cases documented by MRI and arthroscopy within one month from injury underwent ACL reconstruction using ST-G, and arthroscopy was performed again after surgery. The mean term between reconstruction and postoperative arthroscopy was twelve months. The cartilage damage on arthroscopy was compared with the intramedullary lesion on MRI. Cartilage damage was observed in 9 cases (28.1%) during the initial arthroscopy and in 16 cases (50.0%) during the second arthroscopy. Intramedullary lesion was detected in all 32 cases (total: 73 lesions) on MRI. Intramedullary lesion leading to cartilage damage was common in the geographic-type lateral femoral condyle. There was significant difference between the lateral meniscus tear and the cartilage damage of the lateral compartment. (author)

  5. Clinical study of intramedullary route as an alternative for fluid administration in young dogs

    Directory of Open Access Journals (Sweden)

    Pedro Luiz de Camargo

    1996-12-01

    accomplished and rapidly performed. Our results show that intramedullary route is safe and may be of great value as an alternative on the treatment of young dogs with critical hemodynamic alterations when the intravenous route is not accessible.

  6. Do intramedullary implants improve survival in elderly patients with trochanteric fractures? A retrospective study.

    Science.gov (United States)

    Vermesan, D; Prejbeanu, R; Poenaru, D V; Petrescu, H; Apostol, E; Inchingolo, F; Dipalma, G; Abbinante, A; Caprio, M; Potenza, M A; Cagiano, R; Malcangi, G; Inchingolo, A D; Haragus, H

    2015-01-01

    There is currently no consensus regarding superiority of the intramedullary fixation over the sliding hip screw. Regional variation remains high and not backed up by solid evidence. Given these premises we aimed to analyze weather implant preference can influence the postoperative survival. Secondary objectives were determining the trend for implant choice and confounding factors associated with intramedullary nails compared to sliding hip screws. Retrospective data was obtained from patient charts with the main diagnosis of extracapsular/ trochanteric fractures, corresponding to ICD S72.1 codes. Between 2008-2012, 441 patients underwent osteosynthesis with a dynamic hip screw and 155 with intramedullary nail respectively. The living status was determined by comparing the patient identification number against the national population evidence records. The lifetable shows similar survival for both implants over the 5 year period. The yearly mortality was 19.4% for the dynamic hip screw and 21.8% for the intramedullary implant respectively, even though the later were used predominantly in older patients. This age difference is significant according to both parametric and non-parametric tests whereas duration of hospital stay are similar. We found a clear increase in the proportion of intramedullary implants, for a total of 11.2% over the 5 year period. There is no difference for the one year mortality and overall survival between sliding screw plates and intramedullary constructs. A clear increase in the use of intramedullary implants for trochanteric fractures was observed. This is even more apparent for older ages, presumably due to an higher surgeon confidence with the biomechanical stability of the intramedullary constructs.

  7. Extramedullary versus intramedullary tibial cutting guides in megaprosthetic total knee replacement

    Directory of Open Access Journals (Sweden)

    Karade Vikas

    2012-10-01

    Full Text Available Abstract Background In a standard total knee replacement, tibial component alignment is a key factor for the long term success of the surgery. The purpose of this study is to compare the accuracy of extramedullary and intramedullary tibial cutting guides used in indigenous and imported implants respectively, in positioning of the tibial components in megaprosthetic knee replacements. Methods A comparative study of the accuracy of extramedullary and intramedullary tibial cutting guides was carried out in 92 megaprosthetic knee replacements for distal femoral tumors. For the proximal tibia cut for tibial component placement, an extramedullary guide was used in 65 patients and an intramedullary guide was used in 27 patients. Tibial component alignment angles were measured in postoperative X-rays with the help of CAD software. Results There was more varus placement in coronal plane with extramedullary cutting guide (−1.18 +/− 2.4 degrees than the intramedullary guide (−0.34 +/− 2.31 degrees but this did not reach statistical significance. The goal of 90 +/− 2 degrees alignment of tibial component was achieved in 54% of patients in the extramedullary group versus 67% in the intramedullary group. In terms of sagittal plane alignment, extramedullary guide showed less accurate results (2.09 +/− 2.4 degrees than intramedullary guide (0.50 +/− 3.80 degrees for tibial component alignment, though 78% of patients were aligned within the goal of 0–5 degrees of tibial slope angle in extramedullary group versus 63% in intramedullary group. The mean error in the measurements due to rotation of the knee during taking the X-rays was less than 0.1 degrees and distribution of the X-rays with the rotation of knee was similar in both the groups. Conclusions Overall, in megaprosthetic knee replacement intramedullary guides gave more accurate results in sagittal plane and exhibited similar variability as of extramedullary guides in coronal plane.

  8. Complications and Functional Recovery in Treatment of Femoral Shaft Fractures with Unreamed Intramedullary Nailing

    OpenAIRE

    Sadic, Sahmir; Custovic, Svemir; Smajic, Nedim; Fazlic, Mirsad; Vujadinovic, Aleksandar; Hrustic, Asmir; Jasarevic, Mahir

    2014-01-01

    ABSTRACT Introduction: Fracture of the femoral shaft is a common fracture encountered in orthopedic practice. In the 1939, K?ntscher introduced the concept of intramedullary nailing for stabilization of long bone fractures. Intramedullary nailing has revolutionized the treatment of fractures. Material and methods: The study included 37 male patients and 13 female patients, averaged 39?20,5 years (range, 16 to 76 years). Results and discussion: There were 31 left femurs and 21 right femurs fra...

  9. Intramedullary capillary hemangioma of the thoracic spine: case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Paul Santiago

    2009-07-01

    Full Text Available Capillary hemangiomas are benign vascular neoplasms. When associated with the spine, these growths frequently involve the vertebral body, but rarely have they been reported to occur as intradural lesions, while even more rarely occurring in a true intramedullary location. We report a rare case of an intrame-dullary capillary hemangioma of the thoracic spinal cord and a review of the literature.

  10. Elastic scattering

    International Nuclear Information System (INIS)

    Leader, Elliot

    1991-01-01

    With very few unexplained results to challenge conventional ideas, physicists have to look hard to search for gaps in understanding. An area of physics which offers a lot more than meets the eye is elastic and diffractive scattering where particles either 'bounce' off each other, emerging unscathed, or just graze past, emerging relatively unscathed. The 'Blois' workshops provide a regular focus for this unspectacular, but compelling physics, attracting highly motivated devotees

  11. Bactericidal properties of silver films on intramedullary implants

    Science.gov (United States)

    Gallagher, C.; Walker, C.; Cortes, E.; Hettinger, Jeffrey; Krchnavek, R.; Caputo, G. A.; Ostrum, R.

    2011-03-01

    We report on investigations of silver films on titanium and stainless steel substrates as anti-bacterial coatings for intramedullary nails used in orthopedic trauma. Silver films are deposited using a magnetron sputtering technique from a single elemental target. The deposition parameter (energy, pressure, and temperature) dependence of the silver film microstructure and adhesion will be presented. Preliminary measurements of the effectiveness of the silver films as a bactericide on S. aureus bacteria demonstrate that the films are effective destroying the bacteria. The process of this investigation will be presented. Preliminary transmission electron microscopy measurements will also presented which image healthy and damaged bacteria helping to identify the fundamental mechanism leading to the effectiveness of silver as an anti-bacterial coating. We acknowledge the support of Rowan University, College of Liberal Arts and Sciences.

  12. Treatment of humeral shaft fractures with antegrade intramedullary locking nail.

    Science.gov (United States)

    Tsourvakas, Stefanos; Alexandropoulos, Christos; Papachristos, Ioannis; Tsakoumis, Grigorios; Ameridis, Nikolaos

    2011-12-01

    Antegrade interlocked humeral nailing for stabilization of humeral fractures was introduced many years ago, and studies on this method in the orthopedic literature have shown mixed results. The purpose of this investigation was to document the clinical outcome and complications associated with the use of an antegrade intramedullary nail (T2, Stryker) for the humeral fractures. Between 2005 and 2008, 52 fractures of the humeral shaft were treated operatively with this intramedullary nail in our department. Eight patients were polytraumatized, and four patients had an open fracture. The mean age of patients was 51.7 years. Forty-eight patients had an adequate duration of clinical follow-up (a mean of 18 months) for analysis. Complications were recorded, and the time to union was measured. Shoulder and elbow functions were assessed using the Constant Score and the Morrey Score, respectively. Forty-six fractures healed, with a mean time to clinical union of 10.3 weeks. Two patients developed pseudarthroses. There were four adverse events: two proximal screws backed out, one superficial infection at the insertion point, and one fracture at the distal end of the nail. Ninety-one percentage of patients had an excellent or good shoulder function. Five further operations were necessary: two for treatment of pseudarthroses, two for removal the backed out proximal screws, and one wound debridement for superficial infection. Antegrade humeral nailing is a valid therapeutic option for stabilization of humeral shaft fractures. By strictly adhering to the operation technique, the number and the severity of complications can be reduced. When good fracture alignment and stability are obtained, uneventful bone healing with good functional results is the rule.

  13. A novel intramedullary nail for micromotion stimulation of tibial fractures.

    LENUS (Irish Health Repository)

    Dailey, Hannah L

    2011-09-20

    BACKGROUND: Animal studies and clinical trials have suggested that early application of controlled axial micromotion can accelerate healing of long bone fractures compared to rigid fixation. However, experimental investigations of micromotion constructs have been limited to external fixators, which have a higher incidence of complications than intramedullary nails. The purpose of this study was to assess whether a novel intramedullary nail design can generate stimulatory micromotion under minimal weight-bearing loads typical of the early healing period. METHODS: Eight cadaver tibiae were reamed, osteotomised, and implanted with commercially-available IM nails fitted with a custom insert that allowed 1mm of axial micromotion after proximal\\/distal interlocking. Specimens were mounted in a materials testing machine and subjected to cyclic axial loading while interfragmentary motion was measured using an extensometer. Implants were also tested in standard statically-locked mode. FINDINGS: The average force required to cause distraction of the fracture gap in micromotion mode was 37.0 (SD 21.7) N. The mean construct stiffness was 1046.8 (SD 193.6) N\\/mm in static locking mode and 512.4 (SD 99.6) N\\/mm in micromotion mode (significantly different, P<0.001). INTERPRETATION: These results support the development of a micromotion-enabled IM nail because the forces required to cause interfragmentary movements are very low, less than the weight of the hanging shank and foot. In contrast to rigid-fixation nails, which require significant weight-bearing to induce interfragmentary motion, the micromotion-enabled nail may allow movement in non-weight-bearing patients during the early healing period when the benefits of mechanical stimulation are most critical.

  14. Complications during removal of stainless steel versus titanium nails used for intramedullary nailing of diaphyseal fractures of the tibia

    OpenAIRE

    Mustafa Seyhan; Olcay Guler; Mahir Mahirogullari; Ferdi Donmez; Arel Gereli; Serhat Mutlu

    2018-01-01

    Objectives: Intramedullary nailing is the treatment of choice for fractures of the tibial shaft, which might necessitate the nail removal due to complications in the long-term. Although considered as a low-risk procedure, intramedullary nail removal is also associated with certain complications. Here, we compared the most commonly used stainless steel and titanium nails with respect to the complications during removal and clinical outcome for intramedullary nailing of diaphyseal fractures of ...

  15. Complications during removal of stainless steel versus titanium nails used for intramedullary nailing of diaphyseal fractures of the tibia

    OpenAIRE

    Seyhan, Mustafa; Guler, Olcay; Mahirogullari, Mahir; Donmez, Ferdi; Gereli, Arel; Mutlu, Serhat

    2018-01-01

    Objectives Intramedullary nailing is the treatment of choice for fractures of the tibial shaft, which might necessitate the nail removal due to complications in the long-term. Although considered as a low-risk procedure, intramedullary nail removal is also associated with certain complications. Here, we compared the most commonly used stainless steel and titanium nails with respect to the complications during removal and clinical outcome for intramedullary nailing of diaphyseal fractures of t...

  16. Treatment of pediatric femoral shaft fractures by stainless steel and titanium elastic nail system: A randomized comparative trial.

    Science.gov (United States)

    Gyaneshwar, Tank; Nitesh, Rustagi; Sagar, Tomar; Pranav, Kothiyal; Rustagi, Nitesh

    2016-08-01

    in titanium group but five in stainless steel group. Majority of paediatric femoral shaft fractures are now treated operatively by elastic stable intramedullary nails. Operative intervention results in a shorter hospital stay and has economic and social benefits over conservative treatment. The cost of stainless steel nail is one third the cost of titanium nail. However, the clinico-radiological results are not significantly different between titanium and stainless steel nails at one year follow-up as observed by our study.

  17. [Comparison of LCP and locked intramedullary nailing fixation in treatment of tibial diaphysis fractures].

    Science.gov (United States)

    Huang, Peng; Tang, Peifu; Yao, Qi

    2007-11-01

    To evaluate the treatment results of LCP and locked intramedullary nailing for tibial diaphysis fractures. From October 2003 to April 2006, 55 patients with tibial diaphysis fractures (58 fractures) were treated. Of them there were 39 males and 16 females with an average of 39 years years ( 14 to 62 years). The fractures were on the left side in 27 patients and on the right side in 31 patients (3 patients had bilateral involvement). Thirty-four fractures were treated by intramedullary nailing (intramedullary nailing group) and 24 fractures by LCP fixation (LCP group). The average disease course was 3 days (intramedullary nailing group) and 3.1 days (LCP group). The operation time, the range of motion of knee and ankle joints, fracture healing time, and complications were evaluated. The patients were followed up 8-26 months (13 months on average). The operation time was 84.0+/-9.2 min (intramedullary nailing group) and 69.0+/-8.4 min (LCP group); the average cost in hospital was yen 19,297.78 in the intramedullary nailing group and yen 14,116.55 in the LCP group respectively, showing significant differences (P 0.05). The doral flexion and plantar flexion of ankle joint were 13.0+/-1.7 degrees and 41.0+/-2.6 degrees in intramedullary nailing group, and 10.0+/-1.4 degrees and 44.0+/-2.3 degrees in LCP group, showing no significant differences (P>0.05). The mean healing time was 3.3 months in intramedullary nailing group, and 3. 1 months in LCP group. Length discrepancy occurred in 1 case (2.5 cm), delayed union in 1 case and nailing end trouble in 3 cases in intramedullary nailing group; moreover rotation deformity occurred 1 case and anterior knee pain occurred in 6 cases (17.1%). One angulation and open fracture developed osteomyelitis in 1 case 1 week postoperatively and angulation deformity occurred in 1 case of distal-third tibial fractures in LCP group. LCP and locked intramedullary nailing can achieve satisfactory results in treating tibial diaphysis fracture

  18. The effect of retained intramedullary nails on tibial bone mineral density.

    Science.gov (United States)

    Allen, J C; Lindsey, R W; Hipp, J A; Gugala, Z; Rianon, N; LeBlanc, A

    2008-07-01

    Intramedullary nailing has become a standard treatment for adult tibial shaft fractures. Retained intramedullary nails have been associated with stress shielding, although their long-term effect on decreasing tibial bone mineral density is currently unclear. The purpose of this study was to determine if retained tibial intramedullary nails decrease tibial mineral density in patients with successfully treated fractures. Patients treated with statically locked intramedullary nails for isolated, unilateral tibia shaft fractures were studied. Inclusion required that fracture had healed radiographically and that the patient returned to the pre-injury activity level. Data on patient demographic, fracture type, surgical technique, implant, and post-operative functional status were tabulated. Dual energy X-ray absorptiometry was used to measure bone mineral density in selected regions of the affected tibia and the contralateral intact tibia. Image reconstruction software was employed to ensure symmetry of the studied regions. Twenty patients (mean age 43; range 22-77 years) were studied at a mean of 29 months (range 5-60 months) following intramedullary nailing. There was statistically significant reduction of mean bone mineral density in tibiae with retained intramedullary nails (1.02 g/cm(2) versus 1.06 g/cm(2); P=0.04). A significantly greater decrease in bone mineral density was detected in the reamed versus non-reamed tibiae (-7% versus +6%, respectively; P<0.05). The present study demonstrates a small, but statistically significant overall bone mineral density decrease in healed tibiae with retained nails. Intramedullary reaming appears to be a factor potentiating the reduction of tibia bone mineral density in long-term nail retention.

  19. Nonlinear Elasticity

    Science.gov (United States)

    Fu, Y. B.; Ogden, R. W.

    2001-05-01

    This collection of papers by leading researchers in the field of finite, nonlinear elasticity concerns itself with the behavior of objects that deform when external forces or temperature gradients are applied. This process is extremely important in many industrial settings, such as aerospace and rubber industries. This book covers the various aspects of the subject comprehensively with careful explanations of the basic theories and individual chapters each covering a different research direction. The authors discuss the use of symbolic manipulation software as well as computer algorithm issues. The emphasis is placed firmly on covering modern, recent developments, rather than the very theoretical approach often found. The book will be an excellent reference for both beginners and specialists in engineering, applied mathematics and physics.

  20. Do biodegradable magnesium alloy intramedullary interlocking nails prematurely lose fixation stability in the treatment of tibial fracture? A numerical simulation.

    Science.gov (United States)

    Wang, Haosen; Hao, Zhixiu; Wen, Shizhu

    2017-01-01

    Intramedullary interlocking nailing is an effective technique used to treat long bone fractures. Recently, biodegradable metals have drawn increased attention as an intramedullary interlocking nailing material. In this study, numerical simulations were implemented to determine whether the degradation rate of magnesium alloy makes it a suitable material for manufacturing biodegradable intramedullary interlocking nails. Mechano-regulatory and bone-remodeling models were used to simulate the fracture healing process, and a surface corrosion model was used to simulate intramedullary rod degradation. The results showed that magnesium alloy intramedullary rods exhibited a satisfactory degradation rate; the fracture healed and callus enhancement was observed before complete dissolution of the intramedullary rod. Delayed magnesium degradation (using surface coating techniques) did not confer a significant advantage over the non-delayed degradation process; immediate degradation also achieved satisfactory healing outcomes. However, delayed degradation had no negative effect on callus enhancement, as it did not cause signs of stress shielding. To avoid risks of individual differences such as delayed union, delayed degradation is recommended. Although the magnesium intramedullary rod did not demonstrate rapid degradation, its ability to provide high fixation stiffness to achieve earlier load bearing was inferior to that of the conventional titanium alloy and stainless steel rods. Therefore, light physiological loads should be ensured during the early stages of healing to achieve bony healing; otherwise, with increased loading and degraded intramedullary rods, the fracture may ultimately fail to heal. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Magnetic resonance diagnosis of intramedullary tumors of the spinal cord

    Energy Technology Data Exchange (ETDEWEB)

    Scotti, G.; Scialfa, G.; Colombo, N.; Landoni, L.

    1987-03-01

    Fifty patients with intramedullary space occupying lesions were studied with MR from October 1983. Of these 32 were operated on and histological diagnosis together with gross morphological description was available. MR findings were reviewed in search for morphological and signal characteristics capable of providing a better preoperative diagnosis. There were 11 astrocytomas, 10 ependymomas, 5 vascular lesions and 6 ''gliomas''. All lesions usually had signal characteristics different from those of the normal cord, mainly because of prolonged T1 and T2 relaxation times. No specific patterns related either to morphology or signal were found, capable of differentiating the two main historical types. Vascular malformations may be suspected from the presence of serpiginous areas without signal. Tumor nodules within cysts can however be well recognized, thus providing the neurosurgeon with very useful preoperative information. Some characteristics of signal and morphology, are more common for one or the other of the two main groups of tumors. A tumor involving all the cord with a homogeneously prolonged T2 relaxation time is most likely to be an astrocytoma. A small nodule with signal close to normal parenchyma, associated with extensive cysts, is most likely to be an ependymoma.

  2. Intramedullary Venous Drainage System for Distal Fingertip Replantations.

    Science.gov (United States)

    Purisa, Husrev; Ozturk, Muhammed Besir; Kabakas, Fatih; Mersa, Berkan; Ozcelik, Ismail Bulent; Sezer, Ilker

    2017-08-01

    The number of venous anastomoses performed during fingertip replantation is one of the most important factors affecting the success of replantation. However, because vessel diameters decrease in the zone 1 level, vessel anastomoses, especially vein anastomoses, are technically difficult and, thus, cannot be performed in most cases. Alternative venous drainage methods are crucial when any reliable vein repair is not possible. In the literature, so many artery-only replantation techniques have been defined, such as arteriovenous anastomoses, forming an arteriovenous or venocutaneous fistula, manual milking and massage, puncturing, and external bleeding via a fishmouth incision and using a medical leech. It has been shown that, in distal fingertip replantations, the medullary cavity may also be a good way for venous return. In this study, we introduce an alternative intramedullary venous drainage system we developed to facilitate venous drainage in artery-only fingertip replantations. The results of 24 fingertip replantations distal to the nail fold by using this system are presented with a literature review.

  3. Shielding of the patient's gonads during intramedullary interlocking femoral nailing.

    Science.gov (United States)

    Kwong, L M; Johanson, P H; Zinar, D M; Lenihan, M R; Herman, M W

    1990-12-01

    Levels of exposure to radiation were recorded at sixty sites in fifteen patients during intramedullary interlocking femoral nailing. Radiation film dosimeters were placed at four gonadal sites on each subject. A standard male-gonad cup or a pelvic drape of 0.5-millimeter-thick lead-equivalent was put in place to shield the gonads. A second set of four dosimeters was placed external to the shield to approximate unprotected exposure. The total duration of the fluoroscopy averaged five minutes (range, thirty seconds to fourteen minutes). The total exposure to radiation external to the shield was 35 +/- 34 millirems at the male gonadal sites and 17 +/- 11 millirems at the female gonadal sites. With use of the gonadal shield, exposure to radiation was not measurable in thirteen of the fifteen patients. The differences between the exposures of the shielded and unshielded sites to radiation were statistically significant (p less than 0.001). The highest level of gonadal exposure was found with the treatment of proximal femoral fractures and with the use of statically locked nails. Regardless of the conditions, and for all types of fractures and locations, our results demonstrated that gonadal shielding is justified.

  4. Shielding of the patient's gonads during intramedullary interlocking femoral nailing

    International Nuclear Information System (INIS)

    Kwong, L.M.; Johanson, P.H.; Zinar, D.M.; Lenihan, M.R.; Herman, M.W.

    1990-01-01

    Levels of exposure to radiation were recorded at sixty sites in fifteen patients during intramedullary interlocking femoral nailing. Radiation film dosimeters were placed at four gonadal sites on each subject. A standard male-gonad cup or a pelvic drape of 0.5-millimeter-thick lead-equivalent was put in place to shield the gonads. A second set of four dosimeters was placed external to the shield to approximate unprotected exposure. The total duration of the fluoroscopy averaged five minutes (range, thirty seconds to fourteen minutes). The total exposure to radiation external to the shield was 35 +/- 34 millirems at the male gonadal sites and 17 +/- 11 millirems at the female gonadal sites. With use of the gonadal shield, exposure to radiation was not measurable in thirteen of the fifteen patients. The differences between the exposures of the shielded and unshielded sites to radiation were statistically significant (p less than 0.001). The highest level of gonadal exposure was found with the treatment of proximal femoral fractures and with the use of statically locked nails. Regardless of the conditions, and for all types of fractures and locations, our results demonstrated that gonadal shielding is justified

  5. Treatment of femur fractures in young children: a multicenter comparison of flexible intramedullary nails to spica casting in young children aged 2 to 6 years.

    Science.gov (United States)

    Heffernan, Michael J; Gordon, J Eric; Sabatini, Coleen S; Keeler, Kathryn A; Lehmann, Charles L; O'Donnell, June C; Seehausen, Derek A; Luhmann, Scott J; Arkader, Alexandre

    2015-03-01

    Spica casting is the standard of care for femur fractures in children up to 6 years of age. The indications for surgery are controversial. We sought to compare immediate spica casting (Spica) and flexible intramedullary nailing [titanium elastic nailing (TEN)] in a group of children ages 2 to 6 years. We hypothesized that young children can be successfully treated with flexible nails, resulting in faster return to ambulation and an equivalent complication rate when compared with spica casting. This was a multicenter retrospective review of 215 patients, 141 treated with immediate spica casting, and 74 treated with elastic nails. Patient demographics, fracture characteristics, mechanism of injury, associated injuries, outcomes, and complications were recorded and compared between the 2 groups. Patients in the elastic nailing group were more likely to be injured as a pedestrian struck by an automobile (Spica 8% vs. TEN 26%, P=0.001), and had increased rates of associated injuries (Pcasting with shorter time to independent ambulation and full activities. Fractures associated with a high-energy mechanism are especially appropriate for consideration of treatment with TEN. Level III, this was a retrospective comparative study.

  6. Computational Elastic Knots

    KAUST Repository

    Zhao, Xin

    2013-01-01

    Elastic rods have been studied intensively since the 18th century. Even now the theory of elastic rods is still developing and enjoying popularity in computer graphics and physical-based simulation. Elastic rods also draw attention from architects

  7. Intramedullary versus extramedullary alignment of the tibial component in the Triathlon knee

    LENUS (Irish Health Repository)

    Cashman, James P

    2011-08-20

    Abstract Background Long term survivorship in total knee arthroplasty is significantly dependant on prosthesis alignment. Our aim was determine which alignment guide was more accurate in positioning of the tibial component in total knee arthroplasty. We also aimed to assess whether there was any difference in short term patient outcome. Method A comparison of intramedullary versus extramedullary alignment jig was performed. Radiological alignment of tibial components and patient outcomes of 103 Triathlon total knee arthroplasties were analysed. Results Use of the intramedullary was found to be significantly more accurate in determining coronal alignment (p = 0.02) while use of the extramedullary jig was found to give more accurate results in sagittal alignment (p = 0.04). There was no significant difference in WOMAC or SF-36 at six months. Conclusion Use of an intramedullary jig is preferable for positioning of the tibial component using this knee system.

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

    Science.gov (United States)

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

    2016-09-01

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

  9. Intramedullary spinal immature teratoma: resolution of quadriplegia following resection in a 4-week-old infant.

    Science.gov (United States)

    Nickols, Hilary Highfield; Chambless, Lola B; Carson, Robert P; Coffin, Cheryl M; Pearson, Matthew M; Abel, Ty W

    2010-12-01

    Intramedullary spinal cord teratomas are rare entities in infants. Management of these lesions is primarily surgical, with outcome dependent on rapid surgical decompression and complete gross-total tumor resection. The lesions are typically of the mature type, with immature teratomas displaying unique pathological features. The authors report a case of an extensive intramedullary immature teratoma in an infant with resolution of quadriplegia following gross-total radical resection. At the 1-year follow-up, there was radiographic evidence of tumor, and surgical reexploration yielded portions of immature teratoma and extensive gliosis.

  10. Computational Elastic Knots

    KAUST Repository

    Zhao, Xin

    2013-05-01

    Elastic rods have been studied intensively since the 18th century. Even now the theory of elastic rods is still developing and enjoying popularity in computer graphics and physical-based simulation. Elastic rods also draw attention from architects. Architectural structures, NODUS, were constructed by elastic rods as a new method of form-finding. We study discrete models of elastic rods and NODUS structures. We also develop computational tools to find the equilibria of elastic rods and the shape of NODUS. Applications of elastic rods in forming torus knot and closing Bishop frame are included in this thesis.

  11. Stable isotopes

    International Nuclear Information System (INIS)

    Evans, D.K.

    1986-01-01

    Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

  12. Intramedullary cavernous angiomas of the spinal cord. Clinical characteristics of 13 lesions

    International Nuclear Information System (INIS)

    Aoyama, Takeshi; Hida, Kazutoshi; Houkin, Kiyohiro

    2011-01-01

    Magnetic resonance imaging has increased the incidence of the diagnosis of intramedullary cavernous angioma. Surgical therapy tends not to be recommended for asymptomatic lesions, but symptomatic lesions that bleed recurrently should be treated. The natural course of intramedullary cavernous angioma remains unknown and arguments have been raised against the surgical treatment of symptomatic lesions. We reviewed the clinical features of 13 intramedullary cavernous angiomas in 12 patients surgically treated between 1988 and 2009. The 7 men and 5 women were aged from 14 to 60 years, the preoperative interval ranged from 0 to 161 months, and the mean number of hemorrhages in the 13 lesions was 2.5. Sixteen operations were performed to treat the 13 lesions. The surgical approach depended on the lesion location. The outcome of patients with mild to moderate preoperative symptoms (McCormick grades I-III) was significantly better than that of patients with severe symptoms (McCormick grade IV) (p<0.05). Symptomatic intramedullary cavernous angioma tends to bleed repeatedly. The lesion should be surgically removed to avoid further deterioration due to recurrent hemorrhages. The shortest path approach should be selected based on preoperative images and complete removal should be attempted. Residual lesion may be masked by surrounding gliosis, so careful postoperative follow up is necessary. (author)

  13. Metachronous brain and intramedullary spinal cord metastases from nonsmall-cell lung cancer: A case report

    Directory of Open Access Journals (Sweden)

    Wen-Chih Liu

    2012-05-01

    Full Text Available A 44-year-old man had a brain tumor secondary to lung adenocarcinoma and underwent craniectomy to remove the brain tumor. After postoperative whole-brain radiation therapy, he underwent pneumonectomy followed by chemotherapy, mediastinal radiotherapy, and target therapy for lung cancer. Thirty-six months after the initial brain surgery, he suffered from neck pain and right upper limb numbness that rapidly progressed to upper extremity weakness and paralysis in 2 months. Magnetic resonance imaging demonstrated an intramedullary spinal cord lesion at the C4 level. Laminectomy and gross intramedullary tumor removal were performed. The patient’s neurological function improved after the operation. Nevertheless, 4 months after the intramedullary tumor removal, he began to show multiple metastases. Unfortunately, the patient died from respiratory failure 8 months after diagnosis with intramedullary spinal cord metastasis. In this case, early diagnosis and aggressive surgical treatment combined with postoperative radiotherapy and chemotherapy might have provided this patient with a prolonged survival and better quality of life.

  14. Cervical high-intensity intramedullary lesions in achondroplasia : Aetiology, prevalence and clinical relevance

    NARCIS (Netherlands)

    Brouwer, Patrick A.; Lubout, Charlotte M.; van Dijk, J. Marc C.; Vleggeert-Lankamp, Carmen L.

    2012-01-01

    In achondroplastic patients with slight complaints of medullary compression the cervical spinal cord regularly exhibits an intramedullary (CHII) lesion just below the craniocervical junction with no signs of focal compression on the cord. Currently, the prevalence of the lesion in the general

  15. Surgical management of spinal intramedullary tumors: radical and safe strategy for benign tumors.

    Science.gov (United States)

    Takami, Toshihiro; Naito, Kentaro; Yamagata, Toru; Ohata, Kenji

    2015-01-01

    Surgery for spinal intramedullary tumors remains one of the major challenges for neurosurgeons, due to their relative infrequency, unknown natural history, and surgical difficulty. We are sure that safe and precise resection of spinal intramedullary tumors, particularly encapsulated benign tumors, can result in acceptable or satisfactory postoperative outcomes. General surgical concepts and strategies, technical consideration, and functional outcomes after surgery are discussed with illustrative cases of spinal intramedullary benign tumors such as ependymoma, cavernous malformation, and hemangioblastoma. Selection of a posterior median sulcus, posterolateral sulcus, or direct transpial approach was determined based on the preoperative imaging diagnosis and careful inspection of the spinal cord surface. Tumor-cord interface was meticulously delineated in cases of benign encapsulated tumors. Our retrospective functional analysis of 24 consecutive cases of spinal intramedullary ependymoma followed for at least 6 months postoperatively demonstrated a mean grade on the modified McCormick functional schema of 1.8 before surgery, deteriorating significantly to 2.6 early after surgery ( 6 months after surgery). The risk of functional deterioration after surgery should be taken into serious consideration. Functional deterioration after surgery, including neuropathic pain even long after surgery, significantly affects patient quality of life. Better balance between tumor control and functional preservation can be achieved not only by the surgical technique or expertise, but also by intraoperative neurophysiological monitoring, vascular image guidance, and postoperative supportive care. Quality of life after surgery should inarguably be given top priority.

  16. Local and Widespread Hyperalgesia After Isolated Tibial Shaft Fractures Treated with Intramedullary Nailing

    DEFF Research Database (Denmark)

    Larsen, Peter; Elsøe, Rasmus; Graven-Nielsen, Thomas

    2016-01-01

    OBJECTIVES: Knee pain is accepted as a common complication to intramedullary nailing of tibial fractures. However, no studies have systematically studied the pain sequel following tibial fractures. The objective of this study was to assess pain and hyperalgesia from 6 weeks to 12 months postopera...... fracture treated with intramedullary nailing, although no widespread (extrasegmental) hyperalgesia was detected. Such observations may be important for developing the most adequate rehabilitation procedure following a tibial fracture.......OBJECTIVES: Knee pain is accepted as a common complication to intramedullary nailing of tibial fractures. However, no studies have systematically studied the pain sequel following tibial fractures. The objective of this study was to assess pain and hyperalgesia from 6 weeks to 12 months...... postoperatively after intramedullary nailing of tibial shaft fracture. METHODS: A total of 39 patients were included in this 12-month follow-up study. After 6 weeks, 3, 6, and 12 months postoperatively the pain intensity was measured on a visual analog scale (VAS) and the pressure pain sensitivity was assessed...

  17. Intramedullary rodding in type III osteogenesis imperfecta. Effects on neuromotor development in 10 children

    NARCIS (Netherlands)

    Engelbert, R. H.; Helders, P. J.; Keessen, W.; Pruijs, H. E.; Gooskens, R. H.

    1995-01-01

    We studied retrospectively gross motor development and the impact of intramedullary rodding in 10 children with type III osteogenesis imperfecta (OI). There was a pronounced delay in motor development and the order in achieving gross motor milestones differed from the normal developmental sequence.

  18. Intramedullary nailing appears to be superior in pertrochanteric hip fractures with a detached greater trochanter

    DEFF Research Database (Denmark)

    Palm, Henrik; Lysén, Charlotte; Krasheninnikoff, Michael

    2011-01-01

    In recent years, intramedullary nails (INs) for the treatment of pertrochanteric hip fractures have gained prominence relative to conventional, sliding hip screws (SHSs). There is little empirical background for this development, however. A previous series of ours suggested that the use of SHS wa...

  19. Percutaneous Intramedullary Screw Fixation of Distal Fibula Fractures: A Case Series and Systematic Review

    NARCIS (Netherlands)

    Loukachov, Vladimir V.; Birnie, Merel F. N.; Dingemans, Siem A.; de Jong, Vincent M.; Schepers, Tim

    2017-01-01

    The current reference standard for unstable ankle fractures is open reduction and internal fixation using a plate and lag screws. This approach requires extensive dissection and wound complications are not uncommon. The use of intramedullary screw fixation might overcome these issues. The aim of our

  20. Diffusion tensor imaging in inflammatory and neoplastic intramedullary spinal cord lesions: Focusing on fiber tracking

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Jin; Lee, Joon Woo; Lee, Eugene; Kim, Sung Gon; Kang, Yu Suhn; Ahn, Joong Mo; Kang, Heung Sik [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2017-02-15

    Inflammatory and neoplastic intramedullary spinal cord lesions have overlapping clinical features, and it is occasionally difficult to distinguish one from the other on conventional magnetic resonance imaging. We aimed to compare diffusion tensor imaging findings between inflammatory and neoplastic intramedullary spinal cord lesions, with a specific focus on patterns of fiber tracking. Diffusion tensor imaging was performed in patients with either inflammatory or neoplastic intramedullary spinal cord lesions. The fiber tracking patterns (categorized as “intact,” “displaced,” or “interrupted”) were compared between these two groups. Eight patients were included in the study: 5 patients with pathologically or clinically confirmed inflammatory lesions and 3 patients with pathologically or clinically confirmed neoplastic lesions. Among the 5 patients with inflammatory lesions, 2 patients exhibited the displaced pattern and 3 patients exhibited the intact pattern. Among the 3 patients with neoplastic lesions, 1 patient exhibited the intact pattern, 1 patient exhibited the displaced pattern, and 1 patient exhibited the interrupted pattern. In this study, inflammatory and neoplastic intramedullary spinal cord lesions were not clearly differentiated by fiber tracking; both conditions can present with overlapping features such as displaced fibers. The exclusion of inflammatory conditions based on the presence of displaced fibers in fiber tracking images should be avoided.

  1. The accuracy of intramedullary tibial guide of sagittal alignment of PCL-substituting total knee arthroplasty.

    Science.gov (United States)

    Han, Hyuk-Soo; Kang, Seung-Baik; Jo, Chris H; Kim, Sun-Hong; Lee, Jung-Ha

    2010-10-01

    Experimental and clinical studies on the accuracy of the intramedullary alignment method have produced different results, and few have addressed accuracy in the sagittal plane. Reported deviations are not only attributable to the alignment method but also to radiological errors. The purpose of this study was to evaluate the accuracy of the intramedullary alignment method in the sagittal plane using computed tomography (CT) and 3-dimensional imaging software. Thirty-one TKAs were performed using an intramedullary alignment method involving the insertion of a long 8-mm diameter rod into the medullary canal to the distal metaphysis of the tibia. All alignment instruments were set to achieve an ideal varus/valgus angle of 0° in the coronal plane and a tibial slope of 0° in the sagittal plane. The accuracy of the intramedullary alignment system was assessed by measuring the coronal tibial component angle and sagittal tibial slope angles, i.e., angles between the tibial anatomical axis and the tangent to the medial and lateral tibial plateau or the cut-surface. The mean coronal tibial component angle was 88.5° ± 1.2° and the mean tibial component slope in the sagittal plane was 1.6° ± 1.2° without anterior slope. Our intramedullary tibial alignment method, which involves passing an 8-mm diameter long rod through the tibial shaft isthmus, showed good accuracy (less than 3 degrees of variation and no anterior slope) in the sagittal plane in neutral or varus knees.

  2. Percutaneous Intramedullary Screw Fixation of Distal Fibula Fractures: A Case Series and Systematic Review.

    Science.gov (United States)

    Loukachov, Vladimir V; Birnie, Merel F N; Dingemans, Siem A; de Jong, Vincent M; Schepers, Tim

    The current reference standard for unstable ankle fractures is open reduction and internal fixation using a plate and lag screws. This approach requires extensive dissection and wound complications are not uncommon. The use of intramedullary screw fixation might overcome these issues. The aim of our study was to provide an overview of the published data regarding intramedullary screw fixation of fibula fractures combined with a small consecutive case series. We performed a search of published studies to identify the studies in which fibula fractures were treated with percutaneous intramedullary screw fixation. Additionally, all consecutive patients treated for an unstable ankle fracture in a level 1 trauma center using an intramedullary screw were retrospectively included. The literature search identified 6 studies with a total of 180 patients. Wound infection was seen in 1 patient (0.6%), anatomic reduction was achieved in 168 patients (93.3%), and a loss of reduction was seen in 2 patients (1.1%). Implant removal was deemed necessary in 3 patients (1.7%) and nonunion was seen is 2 patients (1.1%). A total of 11 patients, in whom no wound complications occurred, were included in our study. The follow-up duration was a minimum of 12 months. A secondary dislocation was seen in 1 patient, and delayed union was observed after 7.5 months in 1 other patient. In conclusion, intramedullary screw fixation is a safe and adequate method to use for fibula fractures, with a low risk of wound complications. Additional research regarding functional outcome is warranted. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  3. [Results of femoral lengthening over an intramedullary nail and external fixator].

    Science.gov (United States)

    Jasiewicz, Barbara; Kacki, Wojciech; Tesiorowski, Maciej; Potaczek, Tomasz

    2008-01-01

    Current techniques of operative limb lengthening usually are based on distraction osteogenesis. One of the techniques is limb lengthening over an intramedullary nail. The goal of this study is to evaluate the results of femoral lengthening over an intramedullary nail. Between 1999 and 200619 femoral "over nail" lengthenings were performed. There were 7 males and 12 females. Mean patients' age at surgery was 15.8 years, and mean initial femoral shortening was 5.1 cm. Operative technique consisted of one-stage implantation of intramedullary nail and external fixator. Ilizarov apparatus was used in 9 patients, monolateral fixator in 10 cases--ORTHOFIX in 9 patients, Wagner fixator--in 1 patient. Intramedullary nail was locked proximally with screws or Schanz pins from external fixator. After distraction phase, external fixator was removed and distal locking screws were applied. Evaluation criteria: obtained lengthening, time of external fixator, treatment time, healing index, external fixation index, range of motion in hip and knee joints and complications according to Paley. The mean lengthening was 4.6 cm, and mean distraction time was 66.6 days. Mean time of external fixation was 115.5 days, and external fixation index was 26.2 days for centimeter. Healing index was 36.9 days for centimeter. In cases with monolateral fixator, healing index did not differ with the whole group. During treatment 18 complications occurred, for a rate of 0.9 complication per segment. Lengthening over an intramedullary nail reduces the time of external fixator. Over nail femoral lengthening can prevent axis deviation following regenerate bending. Complication rate is similar to lengthenings with the classic Ilizarov technique. There are no differences in the treatment time in relation to the type of external fixator.

  4. Is intramedullary nailing applicable for distal tibial fractures with ankle joint extension?

    Science.gov (United States)

    Beytemür, Ozan; Albay, Cem; Adanır, Oktay; Yüksel, Serdar; Güleç, Mehmet Akif

    2016-12-01

    This study aims to evaluate the functional and radiographic results and treatment complications of AO/OTA (Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association) type 43C1 and C2 fractures treated with intramedullary nailing. We retrospectively evaluated 35 AO/OTA type 43C1 and C2 patients (26 males, 9 females; mean age 39.8±16.9 years; range 19 to 82 years) treated with intramedullary nailing. Two interfragmentary screws out of nail were applied in 10 patients (29%), while one interfragmentary screw out of nail was applied in 17 patients (49%). Intramedullary nailing was applied in eight patients (23%) without external screws. Fracture union, union time, alignment problems, and complications were evaluated. Clinical evaluation of patients was conducted using the Olerud and Molander score and by measuring the ankle joint range of motion. Union was achieved in all 35 patients. Mean union time was 16.5±2.8 weeks (range 12 to 24 weeks) and mean Olerud and Molander score was 88±8.24. Varus deformity was detected in one patient, valgus deformity was detected in two patients, and rotation deformity was detected in one patient. Superficial infection was detected in three patients (9%). Deep infection was not detected in any patient. Intramedullary nailing is not contraindicated for simple intra-articular distal tibial fractures. In these fractures, intramedullary nailing performed in accordance with its technique, with an additional percutaneous screw if necessary, is a successful treatment option with high fracture union rates, high functional results, and low complication rates.

  5. Training effect of using Touch Surgery for intramedullary femoral nailing.

    Science.gov (United States)

    Sugand, Kapil; Mawkin, Mala; Gupte, Chinmay

    2016-02-01

    Simulation in orthopaedic training is becoming increasingly popular and has been widely used in formal curricula. However, these resources are expensive and not easily accessible to every trainee. Other means of disseminating surgical education through virtual reality (VR) multimedia can act as useful adjunct to traditional methods of teaching. One validated VR platform is Touch Surgery, a cognitive task simulation and rehearsal app. The primary objective of this study was to identify the training effect of Touch Surgery intramedullary femoral nailing (IFN) modules using objective performance metrics over six consecutive attempts. Secondary objectives consisted of validated multiple choice questions (MCQ) testing before the first (pre) and after the sixth (post) attempts. 27 medical undergraduates were recruited to complete the decision-making process six consecutive times for four modules on the procedural steps of IFN. The modules consisted of (i) preparing the patient and equipment, (ii) femoral canal preparation, (iii) nail insertion and proximal locking, and (iv) distal locking and closure. Real-time objective performance metrics were obtained, stored electronically and analysed using the median and Bonett-Price 95% confidence intervals from the participants' attempts to assess training effect. Significance was calculated using the Mann-Whitney U test for independent data whilst the Wilcoxon signed ranked test was used for paired data. Significance was set as 2-tailed p-value <0.05. Median performance scores per attempt for all four modules demonstrated a significant improvement ranging from 58 to 115%. Scoring variability and distribution was reduced and more predictable per attempt. Logarithmic learning curves elicited strong positive correlations between the number of attempts and scoring. Mean scores for pre and post-study MCQs tests significantly improved from 83 to 94% in all modules. IFN modules on Touch Surgery app demonstrated a significant training

  6. Primary intramedullary spinal cord lymphoma: a population-based study.

    Science.gov (United States)

    Yang, Wuyang; Garzon-Muvdi, Tomas; Braileanu, Maria; Porras, Jose L; Caplan, Justin M; Rong, Xiaoming; Huang, Judy; Jallo, George I

    2017-03-01

    Primary intramedullary spinal cord lymphoma (PISCL) is a rare diagnosis with poorly understood disease progression. Clarification of the factors associated with survival in PISCL patients is warranted. We conducted a population-based cohort study utilizing prospectively collected data from the Surveillance, Epidemiology, and End Results (SEER) database. Patients with histological diagnosis of primary lymphoma in spinal cord (C72.0) from 1973 to 2012 in the SEER database were included. Multivariable survival analysis between patient, lesion characteristics, and PISCL-related death was performed to adjust for confounding factors. We included 346 PISCL patients in our study. Average age was 56.5 ± 17.8 years, with 62.7% being male. Racial distribution of these patients was white (87.6%), black (8.0%), and other (4.3%). More than half (55.8%) of patients were married. The most prevalent histology of PISCL was diffuse B-cell (46.2%), and the majority (55.2%) were low stage (Ann Arbor stage I/II). Most patients (67.9%) received radiation therapy. Average survival interval of patients with PISCL-related death (n=135, 39.0%) was 27.8 months. General cumulative survival probability at 1 year, 2 years, and 5 years was 73.8%, 67.9%, and 63.1%, respectively. Multivariable accelerated failure time (AFT) regression showed follicular lymphoma (HR:0.25, P=.008) and more recent diagnosis (HR:0.96, P<.001) was positively associated with PISCL-related survival. Conversely, nonwhite race (HR:1.69, P=.046), older age (HR:1.02, P<.001), unmarried status (HR:2.14, P<.001), and higher stage (HR:1.54, P=.022) were negatively associated with survival. Age, race, marital status, tumor histology, tumor stage, and year of diagnosis were associated with survival of PISCL. While most PISCL-related deaths occur within a 1-year period, subsequent slow progression was observed after the first year of survival. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for

  7. "Push-past" reaming as a reduction aid with intramedullary nailing of metadiaphyseal and diaphyseal femoral shaft fractures.

    Science.gov (United States)

    Gary, Joshua L; Munz, John W; Burgess, Andrew R

    2014-06-01

    Eccentric reaming of cortical bone near a fracture site can introduce malalignment when an intramedullary nail is placed. The authors describe a technique of reaming metadiaphyseal and diaphyseal femur fractures in which maintaining reduction at the fracture site is not necessary to obtain an excellent alignment of long bone fractures after intramedullary nailing. They have found that central reaming proximal and distal to, but not at, the fracture site allows for excellent reduction of long bone fractures when the intramedullary nail is passed. The reamer is stopped just before the fracture site and then "pushed" across the fracture prior to resumption of reaming. The authors present "push-past" reaming as a technical trick to facilitate reduction of femoral fractures treated with intramedullary nails and a consecutive series of 18 cases in which excellent postoperative alignment was achieved. Copyright 2014, SLACK Incorporated.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Biomechanical Comparison of an Intramedullary and Extramedullary Free-Tissue Graft Reconstruction of the Acromioclavicular Joint Complex

    Science.gov (United States)

    Garg, Rishi; Javidan, Pooya; Lee, Thay Q.

    2013-01-01

    Background Several different surgical techniques have been described to address the coracoclavicular (CC) ligaments in acromioclavicular (AC) joint injuries. However, very few techniques focus on reconstructing the AC ligaments, despite its importance in providing stability. The purpose of our study was to compare the biomechanical properties of two free-tissue graft techniques that reconstruct both the AC and CC ligaments in cadaveric shoulders, one with an extramedullary AC reconstruction and the other with an intramedullary AC reconstruction. We hypothesized intramedullary AC reconstruction will provide greater anteroposterior translational stability and improved load to failure characteristics than an extramedullary technique. Methods Six matched cadaveric shoulders underwent translational testing at 10 N and 15 N in the anteroposterior and superoinferior directions, under AC joint compression loads of 10 N, 20 N, and 30 N. After the AC and CC ligaments were transected, one of the specimens was randomly assigned the intramedullary free-tissue graft reconstruction while its matched pair received the extramedullary graft reconstruction. Both reconstructed specimens then underwent repeat translational testing, followed by load to failure testing, via superior clavicle distraction, at a rate of 50 mm/min. Results Intramedullary reconstruction provided significantly greater translational stability in the anteroposterior direction than the extramedullary technique for four of six loading conditions (p < 0.05). There were no significant differences in translational stability in the superoinferior direction for any loading condition. The intramedullary reconstructed specimens demonstrated improved load to failure characteristics with the intramedullary reconstruction having a lower deformation at yield and a higher ultimate load than the extramedullary reconstruction (p < 0.05). Conclusions Intramedullary reconstruction of the AC joint provides greater stability in the

  10. Intramedullary Recurrence of a Thoracic Meningioma-Presentation of an Unusual Case and Review of the Literature.

    Science.gov (United States)

    Piazza, Matthew A; Ramayya, Ashwin G; Geiger, Geoffrey A; Alonso-Basanta, Michelle; Nasrallah, MacLean P; Welch, William C; Ozturk, Ali K

    2016-08-01

    Spinal meningiomas are typically extra-axial, slow-growing, benign tumors that arise from the arachnoid cap cells. Intramedullary spinal meningiomas are exceedingly rare with few cases reported in the literature. A 64-year-old man with a history of grade I thoracic meningioma at the T4 level resected initially in 1989 and who required reoperation in 2013 for intradural, extramedullary recurrence of tumor presented again in 2015 with gait difficulty. Magnetic resonance imaging revealed a soft tissue mass at the T3 to T4 levels on the left side of the canal that was mildly enhancing on T1 contrasted sequences. The patient was taken to the operating room, where a purely intramedullary recurrence was discovered without extramedullary extension or a dural-based attachment. The intramedullary tumor was completely resected, and postoperatively the patient recovered well and was at his neurologic baseline. The patient ultimately underwent proton beam radiotherapy because this tumor, although benign, had recurred twice. Intramedullary spinal meningiomas, particularly intramedullary low-grade recurrence of a previously extramedullary tumor, are rare phenomena. Although the pathogenic mechanisms are not well understood, intramedullary recurrence as described in this patient may reflect extrinsic factors related to prior surgical resections in addition to histologic progression. When operating on recurrent extramedullary lesions, aggressive arachnoid dissection may predispose patients to unusual patterns of recurrence. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Intramedullary Mg2Ag nails augment callus formation during fracture healing in mice.

    Science.gov (United States)

    Jähn, Katharina; Saito, Hiroaki; Taipaleenmäki, Hanna; Gasser, Andreas; Hort, Norbert; Feyerabend, Frank; Schlüter, Hartmut; Rueger, Johannes M; Lehmann, Wolfgang; Willumeit-Römer, Regine; Hesse, Eric

    2016-05-01

    Intramedullary stabilization is frequently used to treat long bone fractures. Implants usually remain unless complications arise. Since implant removal can become technically very challenging with the potential to cause further tissue damage, biodegradable materials are emerging as alternative options. Magnesium (Mg)-based biodegradable implants have a controllable degradation rate and good tissue compatibility, which makes them attractive for musculoskeletal research. Here we report for the first time the implantation of intramedullary nails made of an Mg alloy containing 2% silver (Mg2Ag) into intact and fractured femora of mice. Prior in vitro analyses revealed an inhibitory effect of Mg2Ag degradation products on osteoclast differentiation and function with no impair of osteoblast function. In vivo, Mg2Ag implants degraded under non-fracture and fracture conditions within 210days and 133days, respectively. During fracture repair, osteoblast function and subsequent bone formation were enhanced, while osteoclast activity and bone resorption were decreased, leading to an augmented callus formation. We observed a widening of the femoral shaft under steady state and regenerating conditions, which was at least in part due to an uncoupled bone remodeling. However, Mg2Ag implants did not cause any systemic adverse effects. These data suggest that Mg2Ag implants might be promising for intramedullary fixation of long bone fractures, a novel concept that has to be further investigated in future studies. Biodegradable implants are promising alternatives to standard steel or titanium implants to avoid implant removal after fracture healing. We therefore developed an intramedullary nail using a novel biodegradable magnesium-silver-alloy (Mg2Ag) and investigated the in vitro and in vivo effects of the implants on bone remodeling under steady state and fracture healing conditions in mice. Our results demonstrate that intramedullary Mg2Ag nails degrade in vivo over time without

  12. Structural, elastic, optoelectronic and magnetic properties of ...

    Indian Academy of Sciences (India)

    2017-09-22

    Sep 22, 2017 ... 1Laboratoire de Physique Quantique de la Matière et de la ... 5Department of Physics and Astronomy, College of Science, King Saud ... elastic moduli, CdHo2S4 is mechanically stable with a ductile nature and a noticeable.

  13. Finite Element Analysis of Absorbable Sheath to Prevent Stress Shielding of Tibial Interlocking Intramedullary Nail

    Science.gov (United States)

    Dong, Yansheng; Wang, Yongqing; Dong, Limin; Jia, Peng; Lu, Fengcheng

    2017-07-01

    The nail with absorbable sheath (AS nail) is designed to reduce the stress shielding effect of internal fixation with interlocking intramedullary nail. In order to verify its feasibility, two types of the finite element models of internal fixation of tibia with the AS nail and the common metal nail (CM nail) are established using the Softwares of Mimics, Geomagic, SolidWorks and ANSYS according to the CT scanning data of tibia. The result of the finite element analysis shows that the AS nail has great advantages compared with the CM nail in reducing the stress shielding effect in different periods of fracture healing. The conclusion is that the AS nail can realize the static fixation to the dynamic fixation from the early to the later automatically to shorten the time of fracture healing, which also provides a new technique to the interlocking intramedullary nail.

  14. Results of Closed Intramedullary Nailing using Talwarkar Square Nail in Adult Forearm Fractures

    Directory of Open Access Journals (Sweden)

    Nadeem A Lil

    2012-07-01

    Full Text Available The aim of the study was to evaluate results of closed intramedullary nailing using Talwarkar square nails in adult forearm fractures. We prospectively evaluated 34 patients with both bone forearm fractures. The average time to union was 12.8 (SD +3.2 weeks with cast support for a mean of 8.2 weeks. Union was achieved in 31 out of 34 patients. Using the Grace and Eversmann rating system, 17 patients were excellent, 10 were good, and 4 had an acceptable result. Three patients had non-unions, 2 for the radius and one for the ulna. There were two cases of superficial infection, one subject had olecranon bursitis, and one case of radio-ulnar synostosis. Complication rates associated with the use of square nails were lower compared to plate osteosynthesis and locked intramedullary nails. To control rotation post- operatively, there is a need for application of an above-elbow cast after nailing.

  15. Staged Custom, Intramedullary Antibiotic Spacers for Severe Segmental Bone Loss in Infected Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Atul F. Kamath

    2011-01-01

    Full Text Available Introduction. Total hip arthroplasty (THA infections with severe bone loss pose significant reconstructive challenges. We present our experience with two-stage hip reimplantation using an intramedullary, antibiotic-impregnated nail. Methods. Three patients with infected THA with severe proximal femoral bone loss (Mallory type IIIB or greater were treated using a custom antibiotic spacer. Clinical outcomes and any complications were recorded. Average followup was 49 months from final reimplantation. Results. Mean age at spacer placement (stage 1 was 53 years. The mean Harris Hip Score at final followup was 80. Two patients had asymptomatic heterotopic ossification, and one patient had a 2 cm leg-length discrepancy. Conclusions. A custom intramedullary nail antibiotic spacer is a reliable option in the staged management of the infected THA with severe proximal femoral bone loss. Benefits of this technique include limb salvage with maintenance of leg length, soft tissue tension, and functional status.

  16. Elastic scattering and quasi-elastic transfers

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1978-01-01

    Experiments are presented which it will be possible to carry out at GANIL on the elastic scattering of heavy ions: diffraction phenomena if the absorption is great, refraction phenomena if absorption is low. The determination of the optical parameters can be performed. The study of the quasi-elastic transfer reactions will make it possible to know the dynamics of the nuclear reactions, form exotic nuclei and study their energy excitation spectrum, and analyse the scattering and reaction cross sections [fr

  17. Unpredictably Stable

    DEFF Research Database (Denmark)

    Failla, Virgilio; Melillo, Francesca; Reichstein, Toke

    2014-01-01

    Is entrepreneurship a more stable career choice for high employment turnover individuals? We find that a transition to entrepreneurship induces a shift towards stayer behavior and identify job matching, job satisfaction and lock-in effects as main drivers. These findings have major implications...

  18. The occult nature of intramedullary spinal cord metastases from renal cell carcinoma.

    LENUS (Irish Health Repository)

    Zakaria, Zaitun

    2012-01-01

    Renal cell carcinomas (RCC) are characterised by a tendency to metastasise widely, often while remaining occult. Intramedullary spinal cord metastases (ISCM) from RCC may be the presenting feature of the disease or present at any time in the disease course. This case report discusses an ISCM from RCC which became manifested at the time of resection of the primary tumour. We review the literature published on ISCM from RCC from 1990 to date comparing disease characteristics and presentations.

  19. Flexible intramedullary nailing for the treatment of unicameral bone cysts in long bones.

    Science.gov (United States)

    Roposch, A; Saraph, V; Linhart, W E

    2000-10-01

    Unicameral bone cyst is characterized by its tenacity and risk of recurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of flexible intramedullary nailing for the treatment of a unicameral bone cyst with or without a pathological fracture. Flexible intramedullary nailing for the treatment of a unicameral bone cyst was performed in thirty-two patients. Thirty of these patients presented with a pathological fracture; twenty-four were managed immediately with intramedullary nailing, and the other six had been managed conservatively at other clinics before they were referred to our department. The remaining two cysts were detected incidentally. The cyst was located in the humerus in twenty-one patients, in the femur in nine, and in the radius in two. The mean age of the patients at the time of surgery was 9.8 years, and the mean duration of follow-up was 53.7 months. Radiographic evaluation was performed according to the criteria of Capanna et al., and the cyst was classified as completely healed, healed with residual radiolucency (osteolysis), recurred, or having no response. The healing period ranged from three to 105 months. Fourteen cysts healed completely, and sixteen healed with residual radiolucent areas visible on radiographs. There was recurrence of two cysts that had healed with residual radiolucency. All of the cysts in the present study responded to treatment. A change of nails was necessary in nine patients, as the nails had become too short after bone growth. No major complications were observed. Flexible intramedullary nailing provides early stability, which allows early mobilization and thus obviates the need for a plaster cast and decreases the prevalence of the most common complication: a pathological fracture. This method of treatment also allows for an early return to normal activity.

  20. THE RESULT OF INTRAMEDULLARY NAILING WITH BONE GRAFTING OF TIBIA'S PATHOLOGIC FRACTURE

    Directory of Open Access Journals (Sweden)

    V. M. Shapovalov

    2010-01-01

    Full Text Available The authors give the clinical case of successful surgical treatment of patient with tibia's pathologic fracture by intramedullary nailing with bone grafting. The disadvantages of such patients' treatment by plaster immobilization and by some invasive methods like vascular autografting by Ilizarov's method and bone plating were also discussed. The obvious benefits of proposed surgical treatment technique of observed patient category are shown.

  1. Rotation of intramedullary alignment rods affects distal femoral cutting plane in total knee arthroplasty.

    Science.gov (United States)

    Maderbacher, Günther; Matussek, Jan; Keshmiri, Armin; Greimel, Felix; Baier, Clemens; Grifka, Joachim; Maderbacher, Hermann

    2018-02-17

    Intramedullary rods are widely used to align the distal femoral cut in total knee arthroplasty. We hypothesised that both coronal (varus/valgus) and sagittal (extension/flexion) cutting plane are affected by rotational changes of intramedullary femoral alignment guides. Distal femoral cuts using intramedullary alignment rods were simulated by means of a computer-aided engineering software in 4°, 6°, 8°, 10°, and 12° of valgus in relation to the femoral anatomical axis and 4° extension, neutral, as well as 4°, 8°, and 12° of flexion in relation to the femoral mechanical axis. This reflects the different angles between anatomical and mechanical axis in coronal and sagittal planes. To assess the influence of rotation of the alignment guide on the effective distal femoral cutting plane, all combinations were simulated with the rod gradually aligned from 40° of external to 40° of internal rotation. Rotational changes of the distal femoral alignment guides affect both the coronal and sagittal cutting planes. When alignment rods are intruded neutrally with regards to sagittal alignment, external rotation causes flexion, while internal rotation causes extension of the sagittal cutting plane. Simultaneously the coronal effect (valgus) decreases resulting in an increased varus of the cutting plane. However, when alignment rods are intruded in extension or flexion partly contradictory effects are observed. Generally the effect increases with the degree of valgus preset, rotation and flexion. As incorrect rotation of intramedullary alignment guides for distal femoral cuts causes significant cutting errors, exact rotational alignment is crucial. Coronal cutting errors in the distal femoral plane might result in overall leg malalignment, asymmetric extension gaps and subsequent sagittal cutting errors.

  2. Management of Nonunited Talar Fractures With Avascular Necrosis by Resection of Necrotic Bone, Bone Grafting, and Fusion With an Intramedullary Nail.

    Science.gov (United States)

    Abd-Ella, Mohamed Mokhtar; Galhoum, Ahmed; Abdelrahman, Amr Farouk; Walther, Markus

    2017-08-01

    The presence of nonunion of a talar fracture with displacement, together with complete avascular necrosis, is a challenging entity to treat. Twelve patients, 8 men (66.7%) and 4 women (33.3%), with nonunited talar fractures and extensive avascular necrosis of the talus were included. The average age was 27.7 years (range, 19-38 years). After exclusion of infection, the patients underwent resection of necrotic bone, bulk autograft, and fusion using an intramedullary nail. The posterior approach was used in 11 patients and the anterior approach in 1 patient. The primary outcome was solid osseous union at the ankle and subtalar level and between the talar head anteriorly and the posterior construct, as evidenced by computed tomographic examination. Functional assessment was performed with the American Orthopaedic Foot & Ankle Society score and subjective patient satisfaction Results: After a mean follow-up duration of 23 months (range, 12-60 months), solid osseous union was achieved in 8 patients (66.7%). Stable fibrous union was seen in 1 patient (8.3%). Three patients (25%) required reoperation, and osseous fusion was finally achieved. American Orthopaedic Foot & Ankle Society score improved from a mean of 39.3 (range, 12-56) preoperatively to 76.6 (range, 62-86) at last follow-up. Subjective patient satisfaction was graded good or excellent in all cases. Resection of necrotic talar body and bulk autograft with tibiotalocalcaneal fusion by an intramedullary nail through a posterior approach was a reasonable option for the management of type IV posttraumatic talar deformity. Level IV, case series.

  3. Minimally invasive surgical treatment for unstable fractures of the proximal phalanx: intramedullary screw

    Directory of Open Access Journals (Sweden)

    Marcio Aurélio Aita

    2016-02-01

    Full Text Available ABSTRACT OBJECTIVE: To analyze the clinical-functional parameters and quality of life of patients undergoing minimally invasive surgical treatment for extra-articular fractures of the proximal phalanx, using an intramedullary screw (Acutrak(r. METHODS: Between January 2011 and September 2014, a prospective study was conducted on 41 patients (48 fingers with unstable extra-articular fractures of the proximal phalanx, who underwent minimally invasive surgical treatment using an intramedullary screw (Acutrak(r. These patients were evaluated 12 months after the surgery by means of the DASH quality-of-life questionnaire, VAS pain scale, measurement of range of motion (ROM, in degrees and radiographic assessment. RESULTS: All the patients achieved adequate reduction and consolidation of their fractures. There were statistically significant improvements in quality of life on the DASH scale, pain on the VAS scale and range of motion. CONCLUSION: The minimally invasive technique for treating unstable extra-articular fractures of the proximal phalanx using an intramedullary screw (Acutrak(r is effective and safe, and it presents satisfactory clinical-functional results.

  4. Efficacy and Safety of Interlocked Intramedullary Nailing for Open Fracture Shaft of Tibia

    International Nuclear Information System (INIS)

    Ahmad, N.; Awan, A. S.; Sultan, S.; Saifullah, K.; Afridi, S. A.; Afridi, S. K.; Lodhi, F. S.

    2016-01-01

    Background: Due to increasing population and changing human habits the number of accidents and high energy trauma is rising. Management of open fracture tibia is a complex problem and is a challenge for both orthopaedic and plastic surgeons. The study was carried out to ascertain the efficacy and safety of interlocked intra-medullary nailing for open shaft tibial fractures in patients presenting at or after 24 hr of injury. Methods: In this descriptive case series, over a period of 6 moths, 163 consecutive cases of open fracture of tibial shaft were reviewed in terms of clinical profile, time of presentation, and gender distribution. Results: In this study mean age was 30±0.02 years. Males comprised 85 percent of study population while 15 percent were females. Gustilo-I type fracture and Gustilo-II type fracture was diagnosed in 90 percent and 10 percent patients respectively. Thirty three percent patients had wound infection while fracture union was found in 15 percent cases. Moreover interlocked intramedullary nailing for open fracture shaft of tibia was safe in 80 percent patients while this procedure was effective in 85 percent. Conclusion: Un-reamed, interlocked intra-medullary nailing may be considered as a suitable option for treatment of open fractures of tibia. (author)

  5. [Intramedullary nailing combined with cannulated screw in treating femoral condyles fractures].

    Science.gov (United States)

    Shen, Guo-Qing; Zhang, Hao; Long, Da-Fu; Li, Zheng-Wen; Tan, Ying-Dong

    2017-07-25

    To observe the clinical effects of retrograde intramedullary nailing and cannulated screws in the treatment of femoral condylar fracture. From June 2009 to June 2015, 13 patients with femoral condyles fracture were treated by retrograde intramedullary nailing and cannulated screws including 6 males and 7 females with an average age of 46.1 years old ranging from 16 to 76 years old. There were 10 cases of closed fractures, 3 cases of open fraetures. According to AO classification criteriam, 4 cases were type C1, 7 cases were type C2, 2 cases were type C3. Postoperative reduction of fracture and the knee joint function recovery were observed. All patients were followed up for 12 to 36 months with a mean of 24 months. X-ray examination showed that the union time of fracture was 18 to 24 weeks, 21 weeks on average. There were no cases of loosening, breakage of internal fixators and re-fracture. Hospital for Special Surgery(HSS) knee score was 90.07±4.99 at 1 year after the operation. The clinical efficacy for retrograde intramedullary nailing and cannulated screw for the treatment of femoral condyles fracture was excellent. It can improve the anatomical reattachment rate and reduce the complications and promote the knee functional recovery.

  6. Chlorhexidine-releasing implant coating on intramedullary nail reduces infection in a rat model

    Directory of Open Access Journals (Sweden)

    SM Shiels

    2018-03-01

    Full Text Available The use of internal intramedullary nails for long bone fracture fixation is a common practice among surgeons. Bacteria naturally attach to these devices, increasing the risk for wound infection, which can result in non- or malunion, additional surgical procedures and extended hospital stays. Intramedullary nail surface properties can be modified to reduce bacterial colonisation and potentially infectious complications. In the current study, a coating combining a non-fouling property with leaching chlorhexidine for orthopaedic implantation was tested. Coating stability and chlorhexidine release were evaluated in vitro. Using a rat model of intramedullary fixation and infection, the effect of the coating on microbial colonisation and fracture healing was evaluated in vivo by quantitative microbiology, micro-computed tomography, plain radiography, three-point bending and/or histology. Low dose systemic cefazolin was administered to increase the similarities to clinical practice, without overshadowing the effect of the anti-infective coating. When introduced into a contaminated wound, the non-fouling chlorhexidine-coated implant reduced the overall bacteria colonisation within the bone and on the implant, reduced the osteolysis and increased the radiographic union, confirming its potential for reducing complications in wounds at high risk of infection. However, when implanted into a sterile wound, non-union increased. Further studies are required to best optimise the anti-microbial effectiveness, while not sacrificing fracture union.

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

    Science.gov (United States)

    Chuanjun, Chen; Xiaoyang, Chen; Jing, Chen

    2016-10-01

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

  8. MR imaging of intramedullary tumors of the spinal cord: comparison with surgical findings

    International Nuclear Information System (INIS)

    Choe, Du Whan; Hwang, Hee Young; Lee, Hyeon Kyeong; Han, Moon Hee; Kim, In One; Kim, Hyen Jip; Chang, Kee Hyung

    1991-01-01

    To evaluate the capability of MR imaging to localize intramedullary tumors of the spinal cord and to distinguish solid from cystic components. MR images of 12 patients with surgically-proven intramedullary spinal cord tumor were retrospectively reviewed and correlated with surgical findings. Histologic diagnosis consisted of 3 astrocytomas, 4 ependymomas, 2 gangliogliomas, and one case of lipoma, lymphoma, and glioblastoma multiform each. MR scans were obtained on a 2.0T or a 0.5T with T1-and T2-weighted spin-echo pulse sequences in sagittal and axial planes. Contrast enhancement was performed with Gd-DTPA in 9 patients. All tumors expanded the spinal cord and showed an extent of involvement ranging from 2 to 5 vertebral heights, except for the gangliogliomas which involved the spinal cord more extensively. Contrast enhancement was seen in all 9 patients. Intratumoral cavities were observed in 1 out of 3 astrocytomas and 2 gangliogliomas. Peritumoral syringomyelia was seen in 2 out of 4 ependymonas and 2 gangliogliomas. In most cases, the MR findings correlated well with the surgical findings with respect to the extent, distinctness of the tumor margin, intratumoral cavity, and associated syringomyelia. It is concluded that MR imaging is a very useful diagnostic tool in the evaluation of intramedullary spinal cord tumors

  9. Comparison of our self-designed rotary self-locking intramedullary nail and interlocking intramedullary nail in the treatment of long bone fractures.

    Science.gov (United States)

    Liu, Bailian; Xiong, Ying; Deng, Hong; Gu, Shao; Jia, Fu; Li, Qunhui; Wang, Daxing; Gan, Xuewen; Liu, Wei

    2014-07-21

    The purpose of this study is to compare the clinical effects of our self-designed rotary self-locking intramedullary nail (RSIN) and interlocking intramedullary nail (IIN) for long bone fractures. A retrospective study was performed in 1,704 patients who suffered bone fractures and underwent RSIN or IIN operation in our hospital between March 1999 and March 2013, including 494 with femoral fractures, 572 with humeral fractures, and 638 with tibial fractures. Among them, 634 patients were followed up for more than 1 year. The operative time, intraoperative blood loss, postoperative complications, healing rate, and the excellent and good rate of functional recovery were compared between two groups. Compared with IIN group, RSIN group exhibited significantly shorter operative time and less intraoperative blood loss no matter for humeral, femoral, or tibial fractures (all p fractures (both p fracture. In IIN group, nail breakage or loosening occurred in 7 patients with femoral fractures and 16 patients with tibial fractures, radial nerve injury was observed in 8 patients with humeral fractures, and incision infection was present in 2 patients with humeral fractures and 1 patient with femoral fracture. The complication rate of IIN group was significantly higher than that of RSIN group (p knee, and ankle joint functional recovery between RSIN group and IIN group. RSIN may be a reliable and practical alternative method for the treatment of long bone fractures.

  10. Stable particles

    International Nuclear Information System (INIS)

    Samios, N.P.

    1993-01-01

    I have been asked to review the subject of stable particles, essentially the particles that eventually comprised the meson and baryon octets. with a few more additions -- with an emphasis on the contributions made by experiments utilizing the bubble chamber technique. In this activity, much work had been done by the photographic emulsion technique and cloud chambers-exposed to cosmic rays as well as accelerator based beams. In fact, many if not most of the stable particles were found by these latter two techniques, however, the forte of the bubble chamber (coupled with the newer and more powerful accelerators) was to verify, and reinforce with large statistics, the existence of these states, to find some of the more difficult ones, mainly neutrals and further to elucidate their properties, i.e., spin, parity, lifetimes, decay parameters, etc

  11. ElasticSearch cookbook

    CERN Document Server

    Paro, Alberto

    2013-01-01

    Written in an engaging, easy-to-follow style, the recipes will help you to extend the capabilities of ElasticSearch to manage your data effectively.If you are a developer who implements ElasticSearch in your web applications, manage data, or have decided to start using ElasticSearch, this book is ideal for you. This book assumes that you've got working knowledge of JSON and Java

  12. MR imaging of stable posttraumatic spinal cord injury

    International Nuclear Information System (INIS)

    Braun, I.F.; Hoffman, J.C. Jr.; Murphy, C.; Davis, P.C.

    1986-01-01

    Posttraumatic spinal cord cysts have been thought to be infrequent sequelae of spinal trauma. To evaluate the incidence of spinal cord abnormalities in patients who have previously sustained cord trauma, the authors studied the incidence of these changes in clinically stable patients following injury. Twenty-five patients with a history of previous cord injury and stable neurologic status volunteered for MR imaging studies. Studies performed using a 0.5-T and 1.5-T unit revealed focal kinking of the cord at the trauma site as well as intramedullary hypointense areas on T1-weighted images in most volunteers. There was close clinical correlation between MR imaging findings and experimental pathologic data, which suggests that these lesions are much more prevalent than once thought

  13. Stable isotopes

    International Nuclear Information System (INIS)

    Brazier, J.L.; Guinamant, J.L.

    1995-01-01

    According to the progress which has been realised in the technology of separating and measuring isotopes, the stable isotopes are used as preferable 'labelling elements' for big number of applications. The isotopic composition of natural products shows significant variations as a result of different reasons like the climate, the seasons, or their geographic origins. So, it was proved that the same product has a different isotopic composition of alimentary and agriculture products. It is also important in detecting the pharmacological and medical chemicals. This review article deals with the technology, like chromatography and spectrophotometry, adapted to this aim, and some important applications. 17 refs. 6 figs

  14. Stable Tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris [Fermilab

    2018-04-13

    For very heavy quarks, relations derived from heavy-quark symmetry imply novel narrow doubly heavy tetraquark states containing two heavy quarks and two light antiquarks. We predict that double-beauty states will be stable against strong decays, whereas the double-charm states and mixed beauty+charm states will dissociate into pairs of heavy-light mesons. Observing a new double-beauty state through its weak decays would establish the existence of tetraquarks and illuminate the role of heavy color-antitriplet diquarks as hadron constituents.

  15. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  16. ElasticSearch cookbook

    CERN Document Server

    Paro, Alberto

    2015-01-01

    If you are a developer who implements ElasticSearch in your web applications and want to sharpen your understanding of the core elements and applications, this is the book for you. It is assumed that you've got working knowledge of JSON and, if you want to extend ElasticSearch, of Java and related technologies.

  17. Elasticity theory and applications

    CERN Document Server

    Saada, Adel S; Hartnett, James P; Hughes, William F

    2013-01-01

    Elasticity: Theory and Applications reviews the theory and applications of elasticity. The book is divided into three parts. The first part is concerned with the kinematics of continuous media; the second part focuses on the analysis of stress; and the third part considers the theory of elasticity and its applications to engineering problems. This book consists of 18 chapters; the first of which deals with the kinematics of continuous media. The basic definitions and the operations of matrix algebra are presented in the next chapter, followed by a discussion on the linear transformation of points. The study of finite and linear strains gradually introduces the reader to the tensor concept. Orthogonal curvilinear coordinates are examined in detail, along with the similarities between stress and strain. The chapters that follow cover torsion; the three-dimensional theory of linear elasticity and the requirements for the solution of elasticity problems; the method of potentials; and topics related to cylinders, ...

  18. Semiextended approach for intramedullary nailing via a patellar eversion technique for tibial-shaft fractures: Evaluation of the patellofemoral joint.

    Science.gov (United States)

    Yasuda, Tomohiro; Obara, Shu; Hayashi, Junji; Arai, Masayuki; Sato, Kaoru

    2017-06-01

    Intramedullary nail fixation is a common treatment for tibial-shaft fractures, and it offers a better functional prognosis than other conservative treatments. Currently, the primary approach employed during intramedullary nail insertion is the semiextended position is the suprapatellar approach, which involves a vertical incision of the quadriceps tendon Damage to the patellofemoral joint cartilage has been highlighted as a drawback associated with this approach. To avoid this issue, we perform surgery using the patellar eversion technique and a soft sleeve. This method allows the articular surface to be monitored during intramedullary nail insertion. We arthroscopically assessed the effect of this technique on patellofemoral joint cartilage. The patellar eversion technique allows a direct view and protection of the patellofemoral joint without affecting the patella. Thus, damage to the patellofemoral joint cartilage can be avoided. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Elastic interaction energies of defect structures

    International Nuclear Information System (INIS)

    Seitz, E.; de Fontaine, D.

    1976-01-01

    The elastic strain energy between point defects and small disk-shaped clusters of defects are calculated to determine stable configurations. A distortion tensor of tetragonal symmetry is assigned to each impurity atom. The tetragonality ratio t is varied to cover needle-type (t greater than 1), spherical (t = 1) and disk-type (t less than 0) strain fields. To vary the elastic properties of the host material, Fe, Cu, Al, and V were chosen as examples. Computer calculations are based on the microscopic theory of elasticity which emphasizes calculations in discrete Fourier space. Pairs of point defects order along [001] for t less than 1 and along (001) for t = 1 for all host elements. For t greater than 1 fcc lattices and bcc lattices behave differently. It is shown that only certain three dimensional periodic arrangements of parallel and perpendicular disk-like defect clusters are realized for given tetragonality ratio t and host element

  20. Incidence of Avascular Necrosis of the Femoral Head After Intramedullary Nailing of Femoral Shaft Fractures

    Science.gov (United States)

    Kim, Ji Wan; Oh, Jong-Keon; Byun, Young-Soo; Shon, Oog-Jin; Park, Jai Hyung; Oh, Hyoung Keun; Shon, Hyun Chul; Park, Ki Chul; Kim, Jung Jae; Lim, Seung-Jae

    2016-01-01

    Abstract The goal of this study was to determine the incidence of avascular necrosis of the femoral head (AVNFH) after intramedullary nailing of femoral shaft fractures and to identify risk factors for developing AVNFH. We retrospectively reviewed all patients with femoral shaft fractures treated with antegrade intramedullary nailing at 10 institutions. Among the 703 patients enrolled, 161 patients were excluded leaving 542 patients in the study. Average age was 42.1 years with average follow-up of 26.3 months. Patient characteristics and fracture patterns as well as entry point of femoral nails were identified and the incidence of AVNFH was investigated. Patients were divided into 2 groups according to open versus closed physis, open versus closed fractures, and age (<20 versus ≥20 years). Overall incidence of AVNFH was 0.2% (1 of 542): the patient was 15-year-old boy. Of 25 patients with open physis, the incidence of AVNFH was 4%, whereas none of 517 patients with closed physis developed AVNFH (P < 0.001). The incidence of AVNFH in patients aged < 20 versus ≥20 years was 1.1% (1 of 93) and 0.0% (0 of 449), respectively (P = 0.172), which meant that the incidence of AVNFH was 0% in adult with femur shaft fracture. Of 61 patients with open fractures, the incidence of AVNFH was 0%. The number of cases with entry point at the trochanteric fossa or tip of the greater trochanter (GT) was 324 and 218, respectively, and the incidence of AVNFH was 0.3% and 0.0%, respectively (P = 0.412). In patients aged ≥20 years with isolated femoral shaft fracture, there was no case of AVNFH following antegrade intramedullary nailing regardless of the entry point. Therefore, our findings suggest that the risk of AVNFH following antegrade femoral nailing is extremely low in adult patients. PMID:26844518

  1. Spinal diffusion tensor tractography for differentiation of intramedullary tumor-suspected lesions

    Energy Technology Data Exchange (ETDEWEB)

    Egger, K., E-mail: karl.egger@uniklinik-freiburg.de [Department of Neuroradiology, University Medical Center Freiburg, Breisacher Straße 64, 79106 Freiburg (Germany); Hohenhaus, M. [Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106 Freiburg (Germany); Van Velthoven, V. [Department of Neurosurgery, UZ Brussel, Laarbeeklaan 101, 1090 Brussel (Belgium); Heil, S.; Urbach, H. [Department of Neuroradiology, University Medical Center Freiburg, Breisacher Straße 64, 79106 Freiburg (Germany)

    2016-12-15

    Background and purpose: Primary MRI diagnosis of spinal intramedullary tumor-suspected lesions can be challenging and often requires spinal biopsy or resection with a substantial risk of neurological deficits. We evaluated whether Diffusion Tensor Imaging (DTI) tractography can facilitate the differential diagnosis. Materials and methods: Twenty-five consecutive patients with an intramedullary tumor-suspected lesion considered for spinal surgery were studied with a Diffusion-weighted multi-shot read out segmented EPI sequence (RESOLVE). White matter tracts (“streamlines”) were calculated using the FACT algorithm and visually co-registered to a T2-weighted 3D sequence. The fused images were assessed concerning spinal streamline appearance as normal, displaced or terminated. Definite diagnosis was verified by histological analysis or further clinical work-up. Results: All patients with normal appearing streamlines (n = 6) showed an acute inflammatory demyelinating pathology in the further clinical work-up. In 10 patients streamline displacing lesions were found from which 5 patients underwent a surgical treatment with histologically confirmed low-grade tumors like ependymomas and pilocytic astrocytomas. In nine patients streamlines were terminated, from which 6 patients received a histology proven diagnoses with a more heterogenous spectrum (3 cases of high grade tumor, 1 case of low grade tumor with intralesional hemorrhage and 2 cases with gliosis but no tumor cells). Conclusion: Using multi-shot DTI spinal tractography acute inflammatory lesions can be differentiated from other tumorous intramedullary lesions. The entity diagnosis of spinal tumors seems to be more challenging, primarily due to the variety of factors like invasivity, expansion or intralesional hemorrhage.

  2. Comparing hospital outcomes between open and closed tibia fractures treated with intramedullary fixation.

    Science.gov (United States)

    Smith, Evan J; Kuang, Xiangyu; Pandarinath, Rajeev

    2017-07-01

    Tibial shaft fractures comprise a large portion of operatively treated long bone fractures, and present with the highest rate of open injuries. Intramedullary fixation has become the standard of care for both open and closed injuries. The rates of short term complications and hospital length of stay for open and closed fractures treated with intramedullary fixation is not fully known. Previous series on tibia fractures were performed at high volume centers, and data were not generalizable, further they did not report on length of stay and the impact of preoperative variables on infections, complications and reoperation. We used a large surgical database to compare these outcomes while adjusting for preoperative risk factors. Data were extracted from the ACS-NSQIP database from 2005 to 2014. Cases were identified based on CPT codes for intramedullary fixation and categorized as closed vs open based on ICD9 code. In addition to demographic and case data, primary analysis examined correlation between open and closed fracture status with infection, complications, reoperation and hospital length of stay. Secondary analysis examined preoperative variables including gender, race, age, BMI, and diabetes effect on outcomes. There were 272 cases identified. There were no significant demographic differences between open and closed tibia fracture cases. Open fracture status did not increase the rate of infection, 30day complications, reoperation, or length of stay. The only preoperative factor that correlated with length of stay was age. There was no correlation between BMI, presence of insulin dependent and nondependent diabetes, and any outcome measure. When considering the complication rates for open and closed tibial shaft fractures treated with intramedullary fixation, there is no difference between 30-day complication rate, length of stay, or return to the operating room. Our reported postoperative infection rates were comparable to previous series, adding validity to

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

    Directory of Open Access Journals (Sweden)

    Mahmoud A El-Rosasy

    2012-01-01

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

  4. A 51-year-old man with intramedullary spinal cord abscess having a patent foramen ovale

    Science.gov (United States)

    Higuchi, Kanako; Ishihara, Hiroyuki; Okuda, Shiho; Kanda, Fumio

    2011-01-01

    The authors report a case of a 51-year-old man with intramedullary spinal cord abscess (ISCA) having a patent foramen ovale (PFO). He developed fever and tetraplegia after a recent dental treatment. MRI showed ISCA with longitudinal swelling from the upper cervical to the lumbar spinal cord. Cerebrospinal fluid (CSF) analysis indicated bacterial meningitis, and the culture of CSF revealed Streptococcus viridans. Transoesophageal echocardiography revealed the existence of a PFO. We suspected another possibility other than systemic bacteraemia, that paradoxical bacteric embolisation through PFO after the dental treatment caused ISCA. While several reports of brain abscess with PFO are available, this is the first report of ISCA with PFO. PMID:22696715

  5. The efficacy of single-stage open intramedullary nailing of neglected femur fractures.

    Science.gov (United States)

    Boopalan, P R J V C; Sait, Azad; Jepegnanam, Thilak Samuel; Matthai, Thomas; Varghese, Viju Daniel

    2014-02-01

    Neglected femur fractures are not rare in the developing world. Treatment options include single-stage open reduction and intramedullary nailing, or open release, skeletal traction, and then second-stage open intramedullary nailing, with bone grafting. Single-stage procedures have the potential advantage of avoiding neurovascular complications secondary to acute lengthening, but they require a second operation, with potentially increased resource use and infection risk. We sought to determine the (1) likelihood of union, (2) complications and reoperations, and (3) functional results with single-stage open intramedullary nailing without bone grafting in patients with neglected femur fractures. Between January 2003 and December 2007, 17 consecutive patients presented to our practice with neglected femoral shaft fractures. All were treated with single-stage nailing without bone grafting. There were 15 men and two women with a median age of 27 years. The average time from fracture to treatment was 13 weeks (range, 4-44 weeks). Eleven patients underwent open nailing with interlocked nails and six were treated with cloverleaf Kuntscher nails. Patients were followed for a minimum of 6 months (mean, 33 months; range, 6-72 months). The mean preoperative ROM of the knee was 28° (range, 10°-150°) and femoral length discrepancy was 3.1 cm (range, 1-5 cm). All fractures united and the mean time to union was 16 weeks (range, 7-32 weeks). There were no neurologic complications secondary to acute lengthening. The mean postoperative ROM of the knee was 130° (range, 60°-150°). All patients were able to return to preinjury work. Sixteen patients regained their original femoral length. One-stage open intramedullary nailing of neglected femoral diaphyseal fractures without bone grafting was safe and effective, and obviated the need for a two-stage approach. Although the findings need to be replicated in larger numbers of patients, we believe this technique may be useful in

  6. Statistical mechanics of elasticity

    CERN Document Server

    Weiner, JH

    2012-01-01

    Advanced, self-contained treatment illustrates general principles and elastic behavior of solids. Topics include thermoelastic behavior of crystalline and polymeric solids, interatomic force laws, behavior of solids, and thermally activated processes. 1983 edition.

  7. Elasticity of energy consumption

    International Nuclear Information System (INIS)

    Stam, M.

    2004-01-01

    Insight is given into the price elasticities of several energy carriers. Next, attention is paid to the impact of the discussion on changes of the Regulating Energy Levy (REB, abbreviated in Dutch) in the Netherlands [nl

  8. Mastering ElasticSearch

    CERN Document Server

    Kuc, Rafal

    2013-01-01

    A practical tutorial that covers the difficult design, implementation, and management of search solutions.Mastering ElasticSearch is aimed at to intermediate users who want to extend their knowledge about ElasticSearch. The topics that are described in the book are detailed, but we assume that you already know the basics, like the query DSL or data indexing. Advanced users will also find this book useful, as the examples are getting deep into the internals where it is needed.

  9. Open grade III fractures of femoral shaft: Outcome after early reamed intramedullary nailing.

    Science.gov (United States)

    Singh, D; Garg, R; Bassi, J L; Tripathi, S K

    2011-09-01

    Open grade III fractures of femur are a challenging therapeutic problem as most of them are associated with multiple trauma. Method used for skeletal stabilization of these fractures should limit further soft tissue damage, bacterial spread and morbidity in addition to its ease of application, providing mechanical support and restoring normal alignment. Forty-six patients with open grade III fractures of femoral shaft were included in the study. There were 10 grade IIIA, 34 grade IIIB and two grade IIIC fractures that were treated with early reamed intramedullary nailing with adequate management of soft tissue. Patients were reviewed retrospectively. Mean time of union was 27 weeks. Infection rate was 4% and non-union rate was 9%. There were two cases (4%) with limb shortening. No case of angular or rotational deformity was noted. Early reamed intramedullary nailing for open grade III fractures of femoral shaft, after giving due respect to the soft tissue injury, gives satisfactory results with proper alignment, good range of motion, short rehabilitation period and low infection rate. Level IV. Retrospective therapeutic study. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  10. Complications and functional recovery in treatment of femoral shaft fractures with unreamed intramedullary nailing.

    Science.gov (United States)

    Sadic, Sahmir; Custovic, Svemir; Smajic, Nedim; Fazlic, Mirsad; Vujadinovic, Aleksandar; Hrustic, Asmir; Jasarevic, Mahir

    2014-01-01

    Fracture of the femoral shaft is a common fracture encountered in orthopedic practice. In the 1939, Küntscher introduced the concept of intramedullary nailing for stabilization of long bone fractures. Intramedullary nailing has revolutionized the treatment of fractures. The study included 37 male patients and 13 female patients, averaged 39 +/- 20.5 years (range, 16 to 76 years). There were 31 left femurs and 21 right femurs fractured. 46 fractures were the result of blunt trauma. Low energy trauma was the cause of fractures in six patients, of which five in elderly females. 49 fractures were closed. Healing time given in weeks was 19.36 +/- 6.1. The overall healing rate was 93.6%. There were three (6.25%) major complications nonunion. There were one (2%) delayed union, one (2%) rotational malunion and no infection. The shortening of 1 cm were in two patients. Antercurvatum of 10 degrees was found in one patient. There was no statistically significant reduction of a motion in the hip and knee (p knee extensors) muscle weakness (p fractures.

  11. The clinical application of absorbable intramedullary nail and claw plate on treating multiple rib fractures.

    Science.gov (United States)

    Chai, X; Lin, Q; Ruan, Z; Zheng, J; Zhou, J; Zhang, J

    2013-08-01

    The absorption intramedullary nail and claw plate indications and efficacy were investigated in the treatment of a life-threatening multiple rib fractures. A retrospective analysis of 248 surgically treated rib fracture patients was performed who admitted to our hospital from March 2007 to December 2012. Intramedullary nailing was performed in 28 cases, a claw-type bone plate was fixed in 141 cases, and a combination of both was fixed in 79 cases. All internal fixation patients were clinically cured except 1 patient died 14 days after a massive pulmonary embolism. The patients with flail chest and floating chest wall causing respiratory and circulatory disorders were promptly corrected. Routine follow-up was from 1 to 2 years, displaced fractures were in 2 cases, and there were 11 cases of internal fixation and extraction. Internal fixation is a simple and reliable method for the treatment of multiple rib fractures. Both internal fixation materials have their pros and cons but the claw bone plate is more robust. The actual selection of appropriate treatment options helps to improve the treatment efficacy.

  12. Estimation of bone perfusion as a function of intramedullary pressure in sheep

    International Nuclear Information System (INIS)

    Rosenthal, M.S.; Lehner, C.E.; Pearson, D.W.; Kanikula, T.M.; Adler, G.G.; Venci, R.; Lanphier, E.H.; De Luca, P.M.

    1985-01-01

    It has been reported previously that following decompression (i.e. diving ascents) the intramedullary pressure (IMP) in bone can rise dramatically and possibly by the mechanism which can induce dysbaric osteonecrosis or the ''silent bends''. If the blood supply for the bone transverses the marrow compartment, than an increase in IMP could cause a temporary decrease in perfusion or hemostasis and hence ischemia leading to bone necrosis. To test this hypothesis, the authors measured the perfusion of bone in sheep as a function of IMP. The bone perfusion was estimated by measuring the perfusion-limited clearance of Ar-41 (Eγ=1293 keV, T/sub 1/2/=1.83 h) from the bone mineral matrix of sheep's tibia. The argon gas was formed in vivo by the fast neutron activation of Ca-44 to Ar-41 following the Ca-44(n,α) reaction. Clearance of Ar-41 was measured by time gated gamma-ray spectroscopy. These results indicate that an elevation of intramedullary pressure can decrease perfusion in bone and may cause bone necrosis

  13. Exposure of surgeons-in-training to radiation during intramedullary fixation of femoral shaft fractures

    International Nuclear Information System (INIS)

    Coetzee, J.C.; Van der Merwe, E.J.

    1992-01-01

    Owing to the continuous turnover of registrars and radiographers, most of the trauma-related orthopedic surgery in this academic hospital is done by inexperienced surgeons-in-training and the fluoroscopy by junior radiographers. This could result in excessive radiation doses. Calibrated lithium fluoride thermoluminescent chips were secured to various parts of the primary surgeon's body to quantify the radiation dose received during the insertion of an intramedullary nail. Closed intramedullary fixation of 15 fractures of the femur was done with interlocking as necessary. The total average exposure time was 14 minutes 45 seconds per procedure. Distal locking took up 31% of this time. The mean radiation dose to the surgeon's eyes and thyroid was 0,13 mGy and to the dominant hand 2,10 mGy. This would allow the performance of about 350 such procedures per year before the maximum permissible dose level was reached. Recommendations to decrease irradiation dosage are made. 6 refs., 6 tabs

  14. Sphenoid Sinus Carcinoma with Intramedullary Spinal Cord Metastasis and Syringomyelia - Report of A Case -

    International Nuclear Information System (INIS)

    Oh, Yoon Kyeong; Kim, Young Sook

    1996-01-01

    Purpose : Primary sphenoid carcinoma is rare. It accounts for 0.3% of all primary paranasal sinus malignancies. Because of the rarity of sphenoid carcinoma, large series of patients with outcome and survival statistics are currently unavailable. So we followed up the 1 case of sphenoid sinus carcinoma treated in our hospital and reported the course of the disease. In a review of case reports and small series of patients, 2-year survival was 7%. Our case is alive at 29 months after diagnosis of sphenoid sinus carcinoma. Intramedullary spinal cord metastasis (ISCM) is an unusual complication of cancer. In our case rapidly progressive paraparesis and urinary retention developed at 25 months after diagnosis of sphenoid sinus carcinoma. MRI of the thoracic spines showed the intramedullary spinal cord tumor mass at T3 and T4 level with accompanying syringomyelia. Here we report a case of ISCM associated with syringomyelia which has developed after primary sphenoid sinus carcinoma with a review of literature about the clinical behavior and treatment of this lesion

  15. Comparing two intramedullary devices for treating trochanteric fractures: A prospective study

    Directory of Open Access Journals (Sweden)

    Kontogeorgakos Vasileios

    2010-02-01

    Full Text Available Abstract Background Intertrochanteric fractures are surgically treated by using different methods and implants. The optional type of surgical stabilization is still under debate. However, between devices with the same philosophy, different design characteristics may substantially influence fracture healing. This is a prospective study comparing the complication and final functional outcome of two intramedullary devices, the intramedullary hip screw (IMHS and the ENDOVIS nail. Materials and methods Two hundred fifteen patients were randomized on admission in two treatment groups. Epidemiology features and functional status was similar between two treatment groups. Fracture stability was assessed according to the Evan's classification. One hundred ten patients were treated with IMHS and 105 with ENDOVIS nail. Results There were no significant statistical differences between the two groups regarding blood loss, transfusion requirements and mortality rate. In contrast, the number of total complications was significantly higher in the ENDOVIS nail group. Moreover, the overall functional and walking competence was superior in the patients treated with the IMHS nail. Conclusions These results indicate that the choice of the proper implant plays probably an important role in the final outcome of surgical treatment of intertrochanteric fractures. IMHS nail allows for accurate surgical technique, for both static and dynamic compression and high rotational stability. IMHS nail proved more reliable in our study regarding nail insertion and overall uncomplicated outcome.

  16. Continuous decompression with intramedullary nailing for the treatment of unicameral bone cysts.

    Science.gov (United States)

    Masquijo, Julio Javier; Baroni, Eduardo; Miscione, Horacio

    2008-08-01

    To evaluate the efficacy of decompression of unicameral bone cysts (UBCs) of the long bones with intramedullary nailing and to compare responses to treatment according to location. We evaluated 48 consecutive patients treated between January 1988 and June 2000. Mean age was 10.3 years. Mean follow-up was 9.8 years. Evaluation was performed according to the radiographic criteria of Capanna. UBCs were located in the proximal humerus (n = 24), humeral shaft (n = 2), proximal femur (n = 19), distal tibia (n = 2) and fibula (n = 1). A total of 62.5% presented a pathological fracture. Successful results were observed in 89.5% (26 total healing, 17 healing with residual radiolucent areas), and there were four recurrences and, in one case, no response to treatment. There was more healing in the humerus than in the femur (92.3% versus 84.2%), and more tendency to restitution ad integrum, although the difference was not statistically significant (P = 0.1499). Intramedullary nailing is a minimally invasive method, which permits early stability and decompresses the cyst allowing healing. Significant differences were not observed among results from different locations.

  17. New Technique for Tibiotalar Arthrodesis Using a New Intramedullary Nail Device: A Cadaveric Study

    Directory of Open Access Journals (Sweden)

    Emmanuel D. Eisenstein

    2016-01-01

    Full Text Available Introduction. Ankle arthrodesis is performed in a variety of methods. We propose a new technique for tibiotalar arthrodesis using a newly designed intramedullary nail. Methods. We proposed development of an intramedullary device for ankle arthrodesis which spared the subtalar joint using a sinus tarsi approach. Standard saw bones models and computer assisted modeling and stress analysis were used to develop different nail design geometries and determine the feasibility of insertion. After the final design was constructed, the device was tested on three cadaveric specimens. Results. Four basic nail geometries were developed. The optimal design was composed of two relatively straight segments, each with a different radius of curvature for their respective tibial and talar component. We successfully implemented this design into three cadaveric specimens. Conclusion. Our newly designed tibiotalar nail provides a new technique for isolated tibiotalar fusion. It utilizes the advantages of a tibiotalar calcaneal nail and spares the subtalar joint. This design serves as the foundation for future research to include compression options across the tibiotalar joint and eventual transition to clinical practice.

  18. Comparison of suprapatellar and infrapatellar intramedullary nailing for tibial shaft fractures: a systematic review and meta-analysis.

    Science.gov (United States)

    Yang, Liqing; Sun, Yuefeng; Li, Ge

    2018-06-14

    Optimal surgical approach for tibial shaft fractures remains controversial. We perform a meta-analysis from randomized controlled trials (RCTs) to compare the clinical efficacy and prognosis between infrapatellar and suprapatellar intramedullary nail in the treatment of tibial shaft fractures. PubMed, OVID, Embase, ScienceDirect, and Web of Science were searched up to December 2017 for comparative RCTs involving infrapatellar and suprapatellar intramedullary nail in the treatment of tibial shaft fractures. Primary outcomes were blood loss, visual analog scale (VAS) score, range of motion, Lysholm knee scores, and fluoroscopy times. Secondary outcomes were length of hospital stay and postoperative complications. We assessed statistical heterogeneity for each outcome with the use of a standard χ 2 test and the I 2 statistic. The meta-analysis was undertaken using Stata 14.0. Four RCTs involving 293 participants were included in our study. The present meta-analysis indicated that there were significant differences between infrapatellar and suprapatellar intramedullary nail regarding the total blood loss, VAS scores, Lysholm knee scores, and fluoroscopy times. Suprapatellar intramedullary nailing could significantly reduce total blood loss, postoperative knee pain, and fluoroscopy times compared to infrapatellar approach. Additionally, it was associated with an improved Lysholm knee scores. High-quality RCTs were still required for further investigation.

  19. Nonlinear elastic waves in materials

    CERN Document Server

    Rushchitsky, Jeremiah J

    2014-01-01

    The main goal of the book is a coherent treatment of the theory of propagation in materials of nonlinearly elastic waves of displacements, which corresponds to one modern line of development of the nonlinear theory of elastic waves. The book is divided on five basic parts: the necessary information on waves and materials; the necessary information on nonlinear theory of elasticity and elastic materials; analysis of one-dimensional nonlinear elastic waves of displacement – longitudinal, vertically and horizontally polarized transverse plane nonlinear elastic waves of displacement; analysis of one-dimensional nonlinear elastic waves of displacement – cylindrical and torsional nonlinear elastic waves of displacement; analysis of two-dimensional nonlinear elastic waves of displacement – Rayleigh and Love nonlinear elastic surface waves. The book is addressed first of all to people working in solid mechanics – from the students at an advanced undergraduate and graduate level to the scientists, professional...

  20. Elastic anisotropy of crystals

    Directory of Open Access Journals (Sweden)

    Christopher M. Kube

    2016-09-01

    Full Text Available An anisotropy index seeks to quantify how directionally dependent the properties of a system are. In this article, the focus is on quantifying the elastic anisotropy of crystalline materials. Previous elastic anisotropy indices are reviewed and their shortcomings discussed. A new scalar log-Euclidean anisotropy measure AL is proposed, which overcomes these deficiencies. It is based on a distance measure in a log-Euclidean space applied to fourth-rank elastic tensors. AL is an absolute measure of anisotropy where the limiting case of perfect isotropy yields zero. It is a universal measure of anisotropy applicable to all crystalline materials. Specific examples of strong anisotropy are highlighted. A supplementary material provides an anisotropy table giving the values of AL for 2,176 crystallite compounds.

  1. Shells on elastic foundations

    International Nuclear Information System (INIS)

    Das, Y.C.; Kedia, K.K.

    1977-01-01

    No realistic analytical work in the area of Shells on Elastic Foundations has been reported in the literature. Various foundation models have been proposed by several authors. These models involve one or more than one parameters to characterise the foundation medium. Some of these models cannot be used to derive the basic equations governing the behaviour of shells on elastic foundations. In the present work, starting from an elastic continuum hypothesis, a mathematical model for foundation has been derived in curvilinear orthogonal coordinates by the help of principle of virtual displacements, treating one of the virtual displacements as known to satisfy certain given conditions at its edge surfaces. In this model, several foundation parameters can be considered and it can also be used for layered medium of both finite and infinite thickness. (Auth.)

  2. Anisotropic elastic plates

    CERN Document Server

    Hwu, Chyanbin

    2010-01-01

    As structural elements, anisotropic elastic plates find wide applications in modern technology. The plates here are considered to be subjected to not only in plane load but also transverse load. In other words, both plane and plate bending problems as well as the stretching-bending coupling problems are all explained in this book. In addition to the introduction of the theory of anisotropic elasticity, several important subjects have are discussed in this book such as interfaces, cracks, holes, inclusions, contact problems, piezoelectric materials, thermoelastic problems and boundary element a

  3. Hybrid elastic solids

    KAUST Repository

    Lai, Yun

    2011-06-26

    Metamaterials can exhibit electromagnetic and elastic characteristics beyond those found in nature. In this work, we present a design of elastic metamaterial that exhibits multiple resonances in its building blocks. Band structure calculations show two negative dispersion bands, of which one supports only compressional waves and thereby blurs the distinction between a fluid and a solid over a finite frequency regime, whereas the other displays super anisotropy-in which compressional waves and shear waves can propagate only along different directions. Such unusual characteristics, well explained by the effective medium theory, have no comparable analogue in conventional solids and may lead to novel applications. © 2011 Macmillan Publishers Limited. All rights reserved.

  4. Hybrid elastic solids

    KAUST Repository

    Lai, Yun; Wu, Ying; Sheng, Ping; Zhang, Zhaoqing

    2011-01-01

    Metamaterials can exhibit electromagnetic and elastic characteristics beyond those found in nature. In this work, we present a design of elastic metamaterial that exhibits multiple resonances in its building blocks. Band structure calculations show two negative dispersion bands, of which one supports only compressional waves and thereby blurs the distinction between a fluid and a solid over a finite frequency regime, whereas the other displays super anisotropy-in which compressional waves and shear waves can propagate only along different directions. Such unusual characteristics, well explained by the effective medium theory, have no comparable analogue in conventional solids and may lead to novel applications. © 2011 Macmillan Publishers Limited. All rights reserved.

  5. The law of elasticity

    Directory of Open Access Journals (Sweden)

    Sergio Cesare Masin

    2010-01-01

    Full Text Available Participants estimated the imagined elongation of a spring while they were imagining that a load was stretching the spring. This elongation turned out to be a multiplicative function of spring length and load weight-a cognitive law analogous to Hooke¿s law of elasticity. Participants also estimated the total imagined elongation of springs joined either in series or in parallel. This total elongation was longer for serial than for parallel springs, and increased proportionally to the number of serial springs and inversely proportionally to the number of parallel springs. The results suggest that participants integrated load weight with imagined elasticity rather than with spring length.

  6. ElasticSearch server

    CERN Document Server

    Rogozinski, Marek

    2014-01-01

    This book is a detailed, practical, hands-on guide packed with real-life scenarios and examples which will show you how to implement an ElasticSearch search engine on your own websites.If you are a web developer or a user who wants to learn more about ElasticSearch, then this is the book for you. You do not need to know anything about ElastiSeach, Java, or Apache Lucene in order to use this book, though basic knowledge about databases and queries is required.

  7. Elastic plastic fracture mechanics

    International Nuclear Information System (INIS)

    Simpson, L.A.

    1978-07-01

    The application of linear elastic fracture mechanics (LEFM) to crack stability in brittle structures is now well understood and widely applied. However, in many structural materials, crack propagation is accompanied by considerable crack-tip plasticity which invalidates the use of LEFM. Thus, present day research in fracture mechanics is aimed at developing parameters for predicting crack propagation under elastic-plastic conditions. These include critical crack-opening-displacement methods, the J integral and R-curve techniques. This report provides an introduction to these concepts and gives some examples of their applications. (author)

  8. [True/Flex intramedullary nailing for forearm shaft fractures. Long-term results].

    Science.gov (United States)

    Trlica, J; Počepcov, I; Kočí, J; Frank, M; Holeček, T; Dědek, T

    2012-01-01

    Presentation of technical experience and the clinical and functional results of intramedullary fixation of forearm shaft fractures. Between January 1994 and December 2009, a total of 96 patients with 144 radial and/or ulnar fractures (ulna, 33; radius,15; both, 48) were treated by nailing (True/Flex®). According to the AO classification there were 22-A, 22-B and 22-C type fractures in 39 (41%), 44 (46%) and 13 (13%).cases, respectively. Of these, 82 (85%) were closed (types: 0, 48; I, 33; II, 1) and 14 (15%) were open (types: I, 13; II, 1; III, 0) fractures. Seventy-eight patients (81%) were followed up and their functional outcomes were evaluated according to the criteria of Anderson et al. The average interval between the operation and final follow-up was 28 months (15 to 96 months) The average time to surgery was 2.2 days (0 to 25 days). Early complications were recorded in 4% of the patients (1x bursitis olecrani; 1x end cup replacement; 1x bending of nails) and late complications in 15% (5x non-union; 2x delay union; 4x bursitis olecrani; 1x ruptured tendon). Bone healing was achieved in 95% of the cases and took on average 16 weeks (7 to 34 weeks). No infection, refracture or synostosis occurred. Primary loss of reduction was recorded in four cases due to distraction in one, bent nails in two and a wrong size of the implant in one; secondary loss of reduction was found in three cases, with two cases of radius shortening and one 10°malrotation. No primary malrotation was recorded, but secondary loss of alignment was seen in the distal part of the radius and the proximal part of the ulna. Functional results according to the Anderson criteria were excellent and good in 87% of the cases. Intramedullary mailing provides good stability to mid- and distal-third shaft fractures of the ulna and mid- and proximalthird shaft fractures of the radius, particularly in AO type A and type B fractures. The technical aspects of the method are analysed in detail in this paper

  9. 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

  10. The treatment of infected nonunion of the tibia following intramedullary nailing by the Ilizarov method.

    Science.gov (United States)

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

    2010-03-01

    The purpose of this study was to demonstrate the effectiveness of the Ilizarov method and circular external fixator in order to eradicate the infection and restore bone union, limb anatomy and functionality in cases with infected nonunion of the tibia following intramedullary nailing. During 7 years nine patients suffering from infected nonunion of the tibia after intramedullary nailing were treated in our department. The series comprised seven men and two women with an average age of 39.7 years (range 21-75 years). The patients had previously undergone an average of 4.8 operations (range 3-6 operations). Active purulent bone infection occurred in all nine patients. Bone defect was present in all patients with a mean size of 5 cm (range 2-12 cm). In three cases with bone defect less than 2 cm, monofocal compression osteosynthesis technique was used. In the rest cases where bone defect exceeded 2 cm, bifocal consecutive distraction-compression osteosynthesis technique was applied. Three patients required a local gastrocnemius flap. The mean follow-up period was 26.6 months (range 13-42 months). Results were evaluated using Paley's functional and radiological scoring system. Bone union was achieved in all nine patients without recurrence of infection during the follow-up period. Bone results were graded as excellent in five cases and good in the rest four cases. Functional results were graded as excellent in three cases, good in four and fare in two cases. Mean external fixation time was 187.4 days (range 89-412 days) and mean lengthening index was 32 days/cm (range 27-39 days/cm). Complications observed included eight grade II pin tract infections, axial deformity at the lengthening site in two cases and at the nonunion site in another two cases. Ankle joint stiffness was detected in five cases. The Ilizarov method may be an effective method in infected nonunions of the tibia following intramedullary nailing. Copyright 2009 Elsevier Ltd. All rights reserved.

  11. Comparison of Primary Hip Spica with Crossed Retrograde Intramedullary Rush Pins for the Management of Diaphyseal Femur Fractures in Children: A Prospective, Randomized Study

    Directory of Open Access Journals (Sweden)

    Mohammad Ruhullah

    2013-12-01

    Conclusions: Intra-medullary crossed Rush pinning is an effective method of paediatric diaphyseal femur fracture fixation as compared to primary hip spica in terms of early weight bearing and restoration of normal anatomy.

  12. Fracton-Elasticity Duality

    Science.gov (United States)

    Pretko, Michael; Radzihovsky, Leo

    2018-05-01

    Motivated by recent studies of fractons, we demonstrate that elasticity theory of a two-dimensional quantum crystal is dual to a fracton tensor gauge theory, providing a concrete manifestation of the fracton phenomenon in an ordinary solid. The topological defects of elasticity theory map onto charges of the tensor gauge theory, with disclinations and dislocations corresponding to fractons and dipoles, respectively. The transverse and longitudinal phonons of crystals map onto the two gapless gauge modes of the gauge theory. The restricted dynamics of fractons matches with constraints on the mobility of lattice defects. The duality leads to numerous predictions for phases and phase transitions of the fracton system, such as the existence of gauge theory counterparts to the (commensurate) crystal, supersolid, hexatic, and isotropic fluid phases of elasticity theory. Extensions of this duality to generalized elasticity theories provide a route to the discovery of new fracton models. As a further consequence, the duality implies that fracton phases are relevant to the study of interacting topological crystalline insulators.

  13. The Law of Elasticity

    Science.gov (United States)

    Cocco, Alberto; Masin, Sergio Cesare

    2010-01-01

    Participants estimated the imagined elongation of a spring while they were imagining that a load was stretching the spring. This elongation turned out to be a multiplicative function of spring length and load weight--a cognitive law analogous to Hooke's law of elasticity. Participants also estimated the total imagined elongation of springs joined…

  14. Autonomic Vertical Elasticity of Docker Containers with ElasticDocker

    OpenAIRE

    Al-Dhuraibi , Yahya; Paraiso , Fawaz; Djarallah , Nabil; Merle , Philippe

    2017-01-01

    International audience; Elasticity is the key feature of cloud computing to scale computing resources according to application workloads timely. In the literature as well as in industrial products, much attention was given to the elasticity of virtual machines, but much less to the elasticity of containers. However, containers are the new trend for packaging and deploying microservices-based applications. Moreover, most of approaches focus on horizontal elasticity, fewer works address vertica...

  15. The multiple V-shaped double peeling of elastic thin films from elastic soft substrates

    Science.gov (United States)

    Menga, N.; Afferrante, L.; Pugno, N. M.; Carbone, G.

    2018-04-01

    In this paper, a periodic configuration of V-shaped double peeling process is investigated. Specifically, an elastic thin film is detached from a soft elastic material by applying multiple concentrated loads periodically distributed with spatial periodicity λ. The original Kendall's idea is extended to take into account the change in elastic energy occurring in the substrate when the detachment fronts propagate. The symmetric configuration typical of a V-peeling process causes the energy release rate to be sensitive to variations of the elastic energy stored in the soft substrate. This results in an enhancement of the adhesion strength because part of the external work required to trigger the peeling mechanism is converted in substrate elastic energy. A key role is played by both spatial periodicity λ and elasticity ratio E/Eh, between tape and substrate elastic moduli, in determining the conditions of stable adhesion. Indeed, the presence of multiple peeling fronts determines a modification of the mechanism of interaction, because deformations close to each peeling front are also affected by the stresses related to the other fronts. Results show that the energy release rate depends on the detached length of the tape so that conditions can be established which lead to an increase of the supported load compared to the classical peeling on rigid substrates. Finally, we also find that for any given value of the load per unit length, an optimum value of the wavelength λ exists that maximizes the tolerance of the system, before unstable propagation of the peeling front can occur.

  16. Rotational Mal-Alignment after Reamed Intramedullary Nailing for tibial shaft fracture.

    Science.gov (United States)

    Khan, Sher Baz; Mohib, Yasir; Rashid, Rizwan Haroon; Rashid, Haroonur

    2016-10-01

    Intra-medullary (IM) nailing is standard of care for unstable tibial shaft fractures. Malrotation is very common but it is under-recognised, inpart because of variation in normal anatomy and partly due to difficulty in accurately assessing rotation. This study was planned to evaluate the frequency of rotational mal-alignment after reamed tibia IMnailing. This cross-sectional study was conducted at Aga khan University Hospital, Karachi, and comprised patients with tibia shaft fractures managed with IMnailing from January to December 2014. All the patients were assessed intra-operatively for rotational alignment using the knee and ankle fluoroscopic images. There were 81 patients with a mean age of 38±16.9 years. There were 64(79%) male patients. Overall the incidence of malrotation was in 20(24.7%) cases. Rotational mal-alignment is one of the preventable complications after IMnailing which can be assesed intra-operatively under fluoroscope.

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

    Science.gov (United States)

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

    2018-03-21

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

  18. Metacarpophalangeal joint of the thumb arthrodesis using intramedullary interlocking screws XMCP™.

    Science.gov (United States)

    Novoa-Parra, C N; Montaner-Alonso, D; Morales-Rodríguez, J

    2017-09-04

    The study objective was to assess the results of a thumb metacarpophalangeal joint (MCPJ) arthrodesis using intramedullary interlocking screws at 25°, XMCP ™ (Extremity Medical, Parsippany, NJ). Radiographs evaluated the angle of arthrodesis, time of fusion and fixation of the implant. Clinical and functional outcomes were assessed using the DASH questionnaire and the VAS scale. Any complications found during surgery or the follow-up period were noted. We studied 9 patients. The mean follow-up was 27.6 months. Patients showed clinical and radiological evidence of fusion in an average of 8 weeks, the angle of fusion was 25°. There were no complications and no implant had to be removed. The XMCP™ system provides a reliable method for MCPJ arthrodesis for several indications and can be used with other procedures in the complex hand. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Combined spinal subdural tuberculous empyema and intramedullary tuberculoma in an HIV-positive patient

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, Giovanni [Department of Neurosurgery, AZ St Lucas, Groenebriel 1, 9000 Gent (Belgium); Lemmerling, Marc [Department of Neuroradiology, AZ St Lucas, Groenebriel 1, 9000 Gent (Belgium); Nathoo, Narendra [Department of Neurosurgery, Wentworth Hospital, Nelson R. Mandela School of Medicine, University of Natal, Durban (South Africa)

    2003-08-01

    Tuberculous involvement of the spinal subdural and intramedullary compartments is extremely uncommon. Simultaneous involvement of both compartments has never been reported, to our knowledge. We present an HIV-positive patient with such kind of combined involvement. Diagnosis was made on the basis of a prior history of pulmonary tuberculous infection and a positive therapeutic response to antituberculous chemotherapy. Magnetic resonance imaging is the diagnostic procedure of choice in order to determine the exact level, site, and size of the disease. Tuberculosis of the spine should always be considered in the differential diagnosis of spinal cord compression if the patient lives in or comes from a region where tuberculosis is endemic or if the patient is immunocompromised. (orig.)

  20. Less-invasive stabilization of rib fractures by intramedullary fixation: a biomechanical evaluation.

    Science.gov (United States)

    Bottlang, Michael; Helzel, Inga; Long, William; Fitzpatrick, Daniel; Madey, Steven

    2010-05-01

    This study evaluated intramedullary fixation of rib fractures with Kirschner wires and novel ribs splints. We hypothesized that rib splints can provide equivalent fixation strength while avoiding complications associated with Kirschner wires, namely wire migration and cutout. The durability, strength, and failure modes of rib fracture fixation with Kirschner wires and rib splints were evaluated in 22 paired human ribs. First, intact ribs were loaded to failure to determine their strength. After fracture fixation with Kirschner wires and rib splints, fixation constructs were dynamically loaded to 360,000 cycles at five times the respiratory load to determine their durability. Finally, constructs were loaded to failure to determine residual strength and failure modes. All constructs sustained dynamic loading without failure. Dynamic loading caused three times more subsidence in Kirschner wire constructs (1.2 mm +/- 1.4 mm) than in rib splint constructs (0.4 mm +/- 0.2 mm, p = 0.09). After dynamic loading, rib splint constructs remained 48% stronger than Kirschner wire constructs (p = 0.001). Five of 11 Kirschner wire constructs failed catastrophically by cutting through the medial cortex, leading to complete loss of stability and wire migration through the lateral cortex. The remaining six constructs failed by wire bending. Rib splint constructs failed by development of fracture lines along the superior and interior cortices. No splint construct failed catastrophically, and all splint constructs retained functional reduction and fixation. Because of their superior strength and absence of catastrophic failure mode, rib splints can serve as an attractive alternative to Kirschner wires for intramedullary stabilization of rib fractures, especially in the case of posterior rib fractures where access for plating is limited.

  1. Exposed versus buried intramedullary implants for pediatric forearm fractures: a comparison of complications.

    Science.gov (United States)

    Kelly, Brian A; Miller, Patricia; Shore, Benjamin J; Waters, Peter M; Bae, Donald S

    2014-12-01

    The purpose of this study was to compare the rate of complications between buried and exposed intramedullary implants after fixation of pediatric forearm fractures. A retrospective comparative cohort study of 339 children treated with intramedullary fixation for displaced forearm fractures between 2004 and 2009 was performed. Implants were left exposed in 128 patients (37.8%) and buried beneath the skin in 208 patients (61.4%); 3 patients had buried and exposed hardware (0.9%). Data on demographics, injury, surgical technique, and complications were analyzed. The buried implant group was older (mean 10.3 vs. 8.5 y; P exposed implant group. The buried group had their implants removed later than the exposed group (median 3.5 vs. 1.2 mo; P exposed implants were successfully removed in the office. Complications were seen in 56 patients (16.5%). There were 16 patients (4.7%) with refracture and 12 patients (3.5%) with infection. The buried and exposed implant groups did not differ significantly with respect to refracture (3.1% vs. 7.0%; P = 0.20), infection (3.5% vs. 2.3%; P = 0.66), or overall complications (14.5% vs. 17.2%; P = 0.87). There was also no difference between groups with respect to loss of reduction, nondelayed or delayed union, loss of motion, hypertrophic granuloma, or tendon rupture. Buried implants were also associated with penetration through the skin (3.9%). Injury to the dominant arm and need for open reduction were significant predictors of complication (OR = 1.01; 95% CI, 1.001-1.012; P = 0.02 and OR = 0.51; 95% CI, 0.264-0.974; P = 0.04, respectively). There were no significant differences seen in number of infections, refractures, or overall complications based on whether implants were left exposed or buried beneath the skin after surgery. Level III, therapeutic.

  2. Non-linear elastic deformations

    CERN Document Server

    Ogden, R W

    1997-01-01

    Classic in the field covers application of theory of finite elasticity to solution of boundary-value problems, analysis of mechanical properties of solid materials capable of large elastic deformations. Problems. References.

  3. Designing interactively with elastic splines

    DEFF Research Database (Denmark)

    Brander, David; Bærentzen, Jakob Andreas; Fisker, Ann-Sofie

    2018-01-01

    We present an algorithm for designing interactively with C1 elastic splines. The idea is to design the elastic spline using a C1 cubic polynomial spline where each polynomial segment is so close to satisfying the Euler-Lagrange equation for elastic curves that the visual difference becomes neglig...... negligible. Using a database of cubic Bézier curves we are able to interactively modify the cubic spline such that it remains visually close to an elastic spline....

  4. Approximation by planar elastic curves

    DEFF Research Database (Denmark)

    Brander, David; Gravesen, Jens; Nørbjerg, Toke Bjerge

    2016-01-01

    We give an algorithm for approximating a given plane curve segment by a planar elastic curve. The method depends on an analytic representation of the space of elastic curve segments, together with a geometric method for obtaining a good initial guess for the approximating curve. A gradient......-driven optimization is then used to find the approximating elastic curve....

  5. Stable Isotope Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissue samples (skin, bone, blood, muscle) are analyzed for stable carbon, stable nitrogen, and stable sulfur analysis. Many samples are used in their entirety for...

  6. Elasticity in Elastics-An in-vitro study.

    Science.gov (United States)

    Kamisetty, Supradeep Kumar; Nimagadda, Chakrapani; Begam, Madhoom Ponnachi; Nalamotu, Raghuveer; Srivastav, Trilok; Gs, Shwetha

    2014-04-01

    Orthodontic tooth movement results from application of forces to teeth. Elastics in orthodontics have been used both intra-orally and extra- orally to a great effect. Their use, combined with good patient co-operation provides the clinician with the ability to correct both anteroposterior and vertical discrepancies. Force decay over a period of time is a major problem in the clinical usage of latex elastics and synthetic elastomers. This loss of force makes it difficult for the clinician to determine the actual force transmitted to the dentition. It's the intent of the clinician to maintain optimal force values over desired period of time. The majority of the orthodontic elastics on the market are latex elastics. Since the early 1990s, synthetic products have been offered in the market for latex-sensitive patients and are sold as nonlatex elastics. There is limited information on the risk that latex elastics may pose to patients. Some have estimated that 0.12-6% of the general population and 6.2% of dental professionals have hypersensitivity to latex protein. There are some reported cases of adverse reactions to latex in the orthodontic population but these are very limited to date. Although the risk is not yet clear, it would still be inadvisable to prescribe latex elastics to a patient with a known latex allergy. To compare the in-vitro performance of latex and non latex elastics. Samples of 0.25 inch, latex and non latex elastics (light, medium, heavy elastics) were obtained from three manufacturers (Forestadent, GAC, Glenroe) and a sample size of ten elastics per group was tested. The properties tested included cross sectional area, internal diameter, initial force generated by the elastics, breaking force and the force relaxation for the different types of elastics. Force relaxation testing involved stretching the elastics to three times marketed internal diameter (19.05 mm) and measuring force level at intervals over a period of 48 hours. The data were

  7. REPARATIVE OSTEOGENESIS DURING TREATMENT OF FRACTURE UNDER TRANSOSSEOUS OSTEOSYNTHESIS AND INTRAMEDULLARY INSERTION OF WIRES WITH HYDROXYAPATITE COATING

    Directory of Open Access Journals (Sweden)

    Iurii M. Irianov, Arnold V. Popkov, Nikolay A. Kiryanov, Tatiana Iu. Karaseva, Evgenii A. Karasev

    2015-04-01

    Full Text Available Background: The problem of improving medical care for patients with the locomotor system injuries is very important especially last time. Material and Methods: Canine open comminuted tibial fractures modelled experimentally, wires with hydroxyapatite coating inserted intramedullary, osteosynthesis performed with the Ilizarov fixator. Regenerated bones investigated 14-360 days after surgery using the techniques of light microscopy, scanning and transmission electron microscopy, and X-ray electron probe microanalysis for histologic sections . Results: It has been found that a zone of active reparative osteo- and angiogenesis forms around the wires, as well as a bone sheath with the properties of osteogenesis conductor and inductor. Fracture consolidation occurs early according to the primary type without cartilaginous and connective tissue formation in bone adhesion. Presented morphological characteristics endovasal angiogenesis. Conclusion: The results of the study evidence of the positive effect of intramedullary wires with hydroxyapatite coating on the course and intensity of reparative osteogenesis during fracture healing

  8. Flexible Intramedullary Nailing for Paediatric Shaft of Femur Fractures – Does the Number of Nails Alter the Outcome?

    Directory of Open Access Journals (Sweden)

    B Kanthimathi

    2011-07-01

    Full Text Available BACKGROUND: The use of flexible intramedullary nailing, allowing micro movement at the fracture site, results in excellent outcomes regardless of the number of nails used. We undertook analysis of the outcomes of flexible nailing with reference to the number of nails used. METHODS: Twenty patients with diaphyseal femur fracture aged 5-15 years were treated with retrograde flexible intramedullary nailing. The number of nails varied from single to multiple. The results were analysed with regard to the number of nails used. RESULTS: The mean patient age was 7.9 years; patients were followed up for a mean duration of 13.2 months. Those with two and three nails had similar results. CONCLUSION: A minimum of two flexible nails is needed for optimal fixation in paediatric femur shaft fractures. Also, limiting the number of implants to two is cost effective, decreases operative time, reduces radiation exposure and offers equal results to that of three nails.

  9. Magnetic resonance imaging of intramedullary meningioma of the spinal cord: case report and review of the literature

    International Nuclear Information System (INIS)

    Covert, S.; Gandhi, D.; Goyal, M.; Woulfe, J.; Belanger, E.; Miller, W.; Modha, A.

    2003-01-01

    Intramedullary meningioma of the spinal cord is an extremely rare tumour. To the best of our knowledge, only 4 cases have been reported in the English literature, and limited information on imaging features is available. We present a further case and review the literature on this entity. Meningiomas are among the most common tumours that occur in the spinal canal, representing about 25% of all adult intraspinal tumours. They are commonly found in the thoracic segment of the spine and are most often intradural-extramedullary. Their location is explained by the way in which they develop. Meningiomas are derived from persistent arachnoid cell remnants in the spinal coverings, most commonly from arachnoid. They are usually adherent to, but do not arise from, dura. We present a case of intramedullary meningioma, a rare clinical entity, discuss the magnetic resonance imaging (MRI) findings and review the 4 cases that have been previously reported. (author)

  10. Intramedullary nailing for the treatment of aseptic femoral shaft non-unions after plating failure: effectiveness and timing.

    Science.gov (United States)

    Megas, Panagiotis; Syggelos, Spyros A; Kontakis, Georgios; Giannakopoulos, Andreas; Skouteris, Georgios; Lambiris, Elias; Panagiotopoulos, Elias

    2009-07-01

    This retrospective, multicentre study aimed to evaluate reamed intramedullary nailing (IMN) for the treatment of 30 cases of aseptic femoral shaft non-union after plating failure. Following nailing, 29 non-unions had healed by a mean 7.93 months. In one case a hypertrophic non-union required renailing after 8 months, using a nail of greater diameter, and united within five further months. Healing times were not related to whether the fracture was open or closed, the type non-union or the type of fracture. The delay from the initial plating to intramedullary nailing had a statistically significant effect on healing time and final outcome. This treatment is cost effective and should be implemented as soon as the non-union is diagnosed.

  11. Heterotopic ossification of the elbow after closed reduction and retrograde intramedullary nailing for radial neck fracture treated by anconeus interposition.

    Science.gov (United States)

    Sreenivas, T; Menon, Jagdish; Nataraj, A R

    2013-12-01

    Heterotopic ossification around the elbow can lead to considerable functional disability. We describe a case of a 42-year-old man who developed heterotopic ossification of his elbow after closed reduction of the elbow dislocation and radial neck fracture and retrograde intramedullary nailing for radial neck fracture. During the follow-up after initial surgery, movements of the elbow were gradually deteriorated and diagnosed as heterotopic ossification of the elbow. Implant removal, radial head excision along with heterotopic mass, and also interposition of the anconeus muscle resulted in improvement of his elbow mobility. At 18 months of follow-up, patient had elbow flexion arc of 15°-110°, 70° of supination, and 50° of pronation without recurrence of heterotopic ossification. The uniqueness of this case lies in the treatment of heterotopic ossification of the elbow to prevent its recurrence, which was developed after retrograde intramedullary nailing for radial neck fracture following closed reduction.

  12. Introduction to linear elasticity

    CERN Document Server

    Gould, Phillip L

    2013-01-01

    Introduction to Linear Elasticity, 3rd Edition, provides an applications-oriented grounding in the tensor-based theory of elasticity for students in mechanical, civil, aeronautical, and biomedical engineering, as well as materials and earth science. The book is distinct from the traditional text aimed at graduate students in solid mechanics by introducing the subject at a level appropriate for advanced undergraduate and beginning graduate students. The author's presentation allows students to apply the basic notions of stress analysis and move on to advanced work in continuum mechanics, plasticity, plate and shell theory, composite materials, viscoelasticity and finite method analysis. This book also:  Emphasizes tensor-based approach while still distilling down to explicit notation Provides introduction to theory of plates, theory of shells, wave propagation, viscoelasticity and plasticity accessible to advanced undergraduate students Appropriate for courses following emerging trend of teaching solid mechan...

  13. Zirconium elasticity modules

    International Nuclear Information System (INIS)

    Vavra, G.

    1978-01-01

    Considered are the limit and the intermediate values of the Young modulus E, modulus of shear G and of linear modulus of compression K obtainable at various temperatures (4.2 to 1133 K) for single crystals of α-zirconium. Determined and presented are the corrected isotropic elasticity characteristics of E, G, K over the above range of temperatures of textured and non-textured α-Zr

  14. Skeletal Adaptation to Intramedullary Pressure-Induced Interstitial Fluid Flow Is Enhanced in Mice Subjected to Targeted Osteocyte Ablation

    OpenAIRE

    Kwon, Ronald Y.; Meays, Diana R.; Meilan, Alexander S.; Jones, Jeremiah; Miramontes, Rosa; Kardos, Natalie; Yeh, Jiunn-Chern; Frangos, John A.

    2012-01-01

    Interstitial fluid flow (IFF) is a potent regulatory signal in bone. During mechanical loading, IFF is generated through two distinct mechanisms that result in spatially distinct flow profiles: poroelastic interactions within the lacunar-canalicular system, and intramedullary pressurization. While the former generates IFF primarily within the lacunar-canalicular network, the latter generates significant flow at the endosteal surface as well as within the tissue. This gives rise to the intrigu...

  15. Complications during removal of stainless steel versus titanium nails used for intramedullary nailing of diaphyseal fractures of the tibia

    Directory of Open Access Journals (Sweden)

    Mustafa Seyhan

    2018-02-01

    Full Text Available Objectives: Intramedullary nailing is the treatment of choice for fractures of the tibial shaft, which might necessitate the nail removal due to complications in the long-term. Although considered as a low-risk procedure, intramedullary nail removal is also associated with certain complications. Here, we compared the most commonly used stainless steel and titanium nails with respect to the complications during removal and clinical outcome for intramedullary nailing of diaphyseal fractures of the tibia. Patients and methods: Sixty-two patients (26 females, 36 males were included in this retrospective study. Of the removed nails, 24 were of stainless steel and 38 of titanium. Preoperative and intraoperative parameters, such as implant discomfort, anterior knee pain, operating time and amount of bleeding, and postoperative outcomes were evaluated for each patient. Results: Titanium nail group had more, but not statistically significant, intraoperative complications than stainless steel group during the removal of nails (p = .4498. Operating time and amount of intraoperative bleeding were significantly higher in titanium group than stainless steel group (p = .0306 and p < .001, respectively. Preoperative SF-36 physical component and KSS scores were significantly lower in patients who had removal of titanium nails than those of stainless steel nails, whereas there was no difference in terms of postoperative SF-36 and KSS scores. Conclusion: In conclusion, although greater bone contact with titanium increases implant stability, nail removal is more difficult, resulting in more longer surgical operation and more intraoperative bleeding. Therefore, we do not recommend titanium nail removal in asymptomatic patients. Keywords: Fractures of tibial shaft, Removal of intramedullary nailing, Stainless steel nail, Titanium nail

  16. Transverse pinning versus intramedullary pinning in fifth metacarpal's neck fractures: A randomized controlled study with patient-reported outcome.

    Science.gov (United States)

    Galal, Sherif; Safwat, Wael

    2017-01-01

    The 5th metacarpal fractures accounts for 38% of all hand fractures given that the neck is the weakest point in metacarpals, so neck fracture is the most common metacarpal fracture. Surgical fixation is also advocated for such fractures to prevent mal-rotation of the little finger which will lead to fingers overlap in a clenched fist. Various methods are available for fixation of such fractures, like intramedullary & transverse pinning. There are very few reports in the literature comparing both techniques. Authors wanted to compare outcomes and complications of transverse pinning versus intramedullary pinning in fifth metacarpal's neck fractures. A single-center, parallel group, prospective, randomized study was conducted at an academic Level 1 Trauma Center from October 2014 to December 2016. A total of 80 patients with 5th metacarpal's neck fractures were randomized to pinning using either transverse pinning (group A) or intramedullary pinning (group B). Patients were assessed clinically on range of motion, patient-reported outcome using the Quick-DASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire & radiographically. Two blinded observers assessed outcomes. At final follow up for each patient (12 months) the statistically significant differences were observed in operative time, the transverse pinning group showed shorter operative time, as well as complication rate as complications were observed only in intramedullary pinning group. No differences were found in range of motion or the Quick -DASH score. Both techniques are equally safe and effective treatment option for 5th metacarpal's neck fractures. The only difference was shorter operative time & less incidence of complications in transverse pinning group. Level II, Therapeutic study.

  17. pp-elastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Aprile, E; Cantale, G; Degli-Agosti, S; Hausammann, R; Heer, E; Hess, R; Lechanoine-LeLuc, C; Leo, W; Morenzoni, S; Onel, Y [Geneva Univ. (Switzerland). Dept. de Physique Nucleaire et Corpusculaire

    1983-01-01

    The aim of the elastic pp experimental program at SIN was to measure enough spin dependent parameters in order to do a direct experimental reconstruction of the elastic scattering amplitudes at a few energies between 400 and 600 MeV and at several angles between 38/sup 0/ cm and 90/sup 0/ cm. This reconstruction was not possible until recently due to lack of experimental data. Information instead has come mainly from phase shift analysis (PSA). The only way to extract the elastic scattering amplitudes without any hypotheses except those of basic symmetries, is to measure a sufficient set of spin dependent parameters at a given angle and energy. With this in view, the authors have measured at 448, 494, 515, 536 and 579 MeV, the polarization, the spin correlation parameters Asub(00nn), Asub(00ss), Asub(00kk), Asub(00ks), the 2-spin parameters Dsub(n0n0), Ksub(n00n), Dsub(s'0s0), Dsub(s'0k0) and the 3-spin parameters Msub(s'0sn), Msub(s'0kn) between 34/sup 0/ cm and 118/sup 0/ cm. A few of these parameters have also been measured at 560 and 470 MeV and at a few energies below 448 MeV. The indices refer to the polarization orientation of the scattered, recoil, beam and target particle respectively.

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

    Science.gov (United States)

    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.

  19. Complications during removal of stainless steel versus titanium nails used for intramedullary nailing of diaphyseal fractures of the tibia.

    Science.gov (United States)

    Seyhan, Mustafa; Guler, Olcay; Mahirogullari, Mahir; Donmez, Ferdi; Gereli, Arel; Mutlu, Serhat

    2018-02-01

    Intramedullary nailing is the treatment of choice for fractures of the tibial shaft, which might necessitate the nail removal due to complications in the long-term. Although considered as a low-risk procedure, intramedullary nail removal is also associated with certain complications. Here, we compared the most commonly used stainless steel and titanium nails with respect to the complications during removal and clinical outcome for intramedullary nailing of diaphyseal fractures of the tibia. Sixty-two patients (26 females, 36 males) were included in this retrospective study. Of the removed nails, 24 were of stainless steel and 38 of titanium. Preoperative and intraoperative parameters, such as implant discomfort, anterior knee pain, operating time and amount of bleeding, and postoperative outcomes were evaluated for each patient. Titanium nail group had more, but not statistically significant, intraoperative complications than stainless steel group during the removal of nails (p = .4498). Operating time and amount of intraoperative bleeding were significantly higher in titanium group than stainless steel group (p = .0306 and p titanium nails than those of stainless steel nails, whereas there was no difference in terms of postoperative SF-36 and KSS scores. In conclusion, although greater bone contact with titanium increases implant stability, nail removal is more difficult, resulting in more longer surgical operation and more intraoperative bleeding. Therefore, we do not recommend titanium nail removal in asymptomatic patients.

  20. Elastic properties of Gum Metal

    International Nuclear Information System (INIS)

    Kuramoto, Shigeru; Furuta, Tadahiko; Hwang, Junghwan; Nishino, Kazuaki; Saito, Takashi

    2006-01-01

    In situ X-ray diffraction measurements under tensile loading and dynamic mechanical analysis were performed to investigate the mechanisms of elastic deformation in Gum Metal. Tensile stress-strain curves for Gum Metal indicate that cold working substantially decreases the elastic modulus while increasing the yield strength, thereby confirming nonlinearity in the elastic range. The gradient of each curve decreased continuously to about one-third its original value near the elastic limit. As a result of this decrease in elastic modulus and nonlinearity, elastic deformability reaches 2.5% after cold working. Superelasticity is attributed to stress-induced martensitic transformations, although the large elastic deformation in Gum Metal is not accompanied by a phase transformation

  1. A prospective, randomised trial comparing closed intramedullary nailing with percutaneous plating in the treatment of distal metaphyseal fractures of the tibia.

    Science.gov (United States)

    Guo, J J; Tang, N; Yang, H L; Tang, T S

    2010-07-01

    We compared the outcome of closed intramedullary nailing with minimally invasive plate osteosynthesis using a percutaneous locked compression plate in patients with a distal metaphyseal fracture in a prospective study. A total of 85 patients were randomised to operative stabilisation either by a closed intramedullary nail (44) or by minimally invasive osteosynthesis with a compression plate (41). Pre-operative variables included the patients' age and the side and pattern of the fracture. Peri-operative variables were the operating time and the radiation time. Postoperative variables were wound problems, the time to union of the fracture, the functional American Orthopaedic Foot and Ankle surgery score and removal of hardware. We found no significant difference in the pre-operative variables or in the time to union in the two groups. However, the mean radiation time and operating time were significantly longer in the locked compression plate group (3.0 vs 2.12 minutes, p fractures had united. Patients who had intramedullary nailing had a higher mean pain score (40 = no pain, 0 = severe pain), [corrected] but better function, alignment and total American Orthopaedic Foot and Ankle surgery scores, although the differences were not statistically significant (p = 0.234, p = 0.157, p = 0.897, p = 0.177 respectively). Three (6.8%) patients in the intramedullary nailing group and six (14.6%) in the locked compression plate group showed delayed wound healing, and 37 (84.1%) in the former group and 38 (92.7%) in the latter group expressed a wish to have the implant removed. We conclude that both closed intramedullary nailing and a percutaneous locked compression plate can be used safely to treat Orthopaedic Trauma Association type-43A distal metaphyseal fractures of the tibia. However, closed intramedullary nailing has the advantage of a shorter operating and radiation time and easier removal of the implant. We therefore prefer closed intramedullary nailing for patients with

  2. Localization of elastic layers by correlated disorder

    International Nuclear Information System (INIS)

    Balents, L.

    1993-01-01

    The equilibrium behavior of a system of elastic layers under tension in the presence of correlated disorder is studied using functional renormalization group techniques. The model exhibits many of the features of the Bose-glass phase of type-II superconductors induced by columnar defects, but may be more directly applicable to charge density waves, incommensurate striped magnetic phases, stacked membranes under tension, vicinal crystal surfaces, or superconducting ''vortex-chains''. Below five dimensions, an epsilon expansion for the stable zero-temperature fixed point yields the properties of the glassy phase. Transverse to the direction of correlation, the randomness induces logarithmic growth of displacements. The absence of a response to a weak applied transverse field (transverse Meissner effect) is demonstrated analytically. In this simple model, the localized phase is stable to point disorder, in contrast to the behavior in the presence of dislocations, in which the converse is believed to be true. (orig.)

  3. Quality of life after antegrade intramedullary nail fixation of humeral fractures: a survey in a selected cohort of Brazilian patients.

    Science.gov (United States)

    Cocco, Luiz Fernando; Ejnisman, Benno; Belangero, Paulo Santoro; Cohen, Moises; Dos Reis, Fernando Baldy

    2018-01-01

    The treatment of humeral fractures remains controversial. Systematic reviews demonstrate similar results between dynamic compression plating and locked intramedullary nailing in the surgical treatment of these fractures. However, it appears that antegrade intramedullary nailing causes higher residual pain in the shoulder. The proposal of this work is to evaluate through the WORC protocol (Western Ontario Rotator Cuff Index) the consequences in the quality of life of patients submitted to osteosynthesis of the humerus with antegrade locked intramedullary nailing. This work is a cohort retrospective study in addition to the application of a questionnaire for self-rated quality of life with its 05 domains (WORC - Western Ontario Rotator Cuff Index) for patients ( N  = 26) classified in the Trauma Sector of the Department of Orthopedics and Traumatology of the Federal University of São Paulo (DOT/UNIFESP) submitted to Humerus Osteosynthesis with Antegrade Locked Intramedullary Nailing. There was also the inclusion of data related to the time since surgery, age, sex, surgical laterality, dominance among members and work leave, which were not considered in the original protocol. After, the data were statistically assessed to evaluate the association between numerical and categorical variables. The overall WORC score was 82.75 ± 17.00 (Mean ± SD) and was not different considering sex, age and postoperative period. Among the WORC domains, both Work and Sport / Recreation Protocols were the most unfavorable factors in the evaluation of patients. Although not statistically significant, those who had the procedure on the dominant side presented a lower quality of life score than those who had the surgery on the non-dominant side. Although non-significant again, those who were away from work had an overall lower quality of life score than those who were not. The WORC Quality of Life Protocol shows good results for evaluating patients submitted to humerus

  4. A symplectic integration method for elastic filaments

    Science.gov (United States)

    Ladd, Tony; Misra, Gaurav

    2009-03-01

    Elastic rods are a ubiquitous coarse-grained model of semi-flexible biopolymers such as DNA, actin, and microtubules. The Worm-Like Chain (WLC) is the standard numerical model for semi-flexible polymers, but it is only a linearized approximation to the dynamics of an elastic rod, valid for small deflections; typically the torsional motion is neglected as well. In the standard finite-difference and finite-element formulations of an elastic rod, the continuum equations of motion are discretized in space and time, but it is then difficult to ensure that the Hamiltonian structure of the exact equations is preserved. Here we discretize the Hamiltonian itself, expressed as a line integral over the contour of the filament. This discrete representation of the continuum filament can then be integrated by one of the explicit symplectic integrators frequently used in molecular dynamics. The model systematically approximates the continuum partial differential equations, but has the same level of computational complexity as molecular dynamics and is constraint free. Numerical tests show that the algorithm is much more stable than a finite-difference formulation and can be used for high aspect ratio filaments, such as actin. We present numerical results for the deterministic and stochastic motion of single filaments.

  5. Form finding in elastic gridshells

    Science.gov (United States)

    Baek, Changyeob; Sageman-Furnas, Andrew O.; Jawed, Mohammad K.; Reis, Pedro M.

    2018-01-01

    Elastic gridshells comprise an initially planar network of elastic rods that are actuated into a shell-like structure by loading their extremities. The resulting actuated form derives from the elastic buckling of the rods subjected to inextensibility. We study elastic gridshells with a focus on the rational design of the final shapes. Our precision desktop experiments exhibit complex geometries, even from seemingly simple initial configurations and actuation processes. The numerical simulations capture this nonintuitive behavior with excellent quantitative agreement, allowing for an exploration of parameter space that reveals multistable states. We then turn to the theory of smooth Chebyshev nets to address the inverse design of hemispherical elastic gridshells. The results suggest that rod inextensibility, not elastic response, dictates the zeroth-order shape of an actuated elastic gridshell. As it turns out, this is the shape of a common household strainer. Therefore, the geometry of Chebyshev nets can be further used to understand elastic gridshells. In particular, we introduce a way to quantify the intrinsic shape of the empty, but enclosed regions, which we then use to rationalize the nonlocal deformation of elastic gridshells to point loading. This justifies the observed difficulty in form finding. Nevertheless, we close with an exploration of concatenating multiple elastic gridshell building blocks.

  6. Stable convergence and stable limit theorems

    CERN Document Server

    Häusler, Erich

    2015-01-01

    The authors present a concise but complete exposition of the mathematical theory of stable convergence and give various applications in different areas of probability theory and mathematical statistics to illustrate the usefulness of this concept. Stable convergence holds in many limit theorems of probability theory and statistics – such as the classical central limit theorem – which are usually formulated in terms of convergence in distribution. Originated by Alfred Rényi, the notion of stable convergence is stronger than the classical weak convergence of probability measures. A variety of methods is described which can be used to establish this stronger stable convergence in many limit theorems which were originally formulated only in terms of weak convergence. Naturally, these stronger limit theorems have new and stronger consequences which should not be missed by neglecting the notion of stable convergence. The presentation will be accessible to researchers and advanced students at the master's level...

  7. Advanced interlocking systems to improve heavy-load-bearing characteristics of flexible intramedullary nailing

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Leopold, E-mail: leopold.berger@tuwien.ac.at [Institute of Building Construction and Technology, TU Wien, Karlsplatz 13/206-4, 1040 Vienna (Austria); Eichler, Johannes [Department of Orthopedics and Orthopedic Surgery, Medical University of Graz, Auenbruggerplatz 5/6, 8036 Graz (Austria); Ryll, E. Jonathan S. [Department of Trauma-, Hand- and Reconstructive Surgery, University Hospital Muenster, Westphalian-Wilhelms University, Muenster (Germany); Fischerauer, Stefan [Department of Traumatology, Medical University of Graz, Auenbruggerplatz 5/6, 8036 Graz (Austria); Raschke, Michael J. [Department of Trauma-, Hand- and Reconstructive Surgery, University Hospital Muenster, Westphalian-Wilhelms University, Muenster (Germany); Kolbitsch, Andreas [Institute of Building Construction and Technology, TU Wien, Karlsplatz 13/206-4, 1040 Vienna (Austria); Castellani, Christoph [Department of Pediatric and Adolescence Surgery, Medical University of Graz, Auenbruggerplatz 34, 8036 Graz (Austria); Weinberg, Annelie-Martina [Department of Orthopedics and Orthopedic Surgery, Medical University of Graz, Auenbruggerplatz 5/6, 8036 Graz (Austria)

    2016-11-01

    Flexible intramedullary nailing (FIN) is a minimally invasive and widespread standard method for osteosynthesis of pediatric long bone fractures. In the case of unstable fractures of the lower extremity, interlocking systems need to be used to prevent axial shortening and subsequent perforation of the nail at its insertion site. In the present study, four different screw-fixed interlocking systems for FINs (Hofer TwinPlug with two 3-mm titanium interlocking screws, Hofer FixPlug with 3-mm titanium interlocking screw, Hofer Plug with 3.5-mm titanium interlocking screw, and Hofer Plug with 3-mm titanium interlocking screw) in comparison with the commonly used Ender stainless steel nails (locked with 3.5-mm screw) were experimentally investigated in cadaveric lamb tibiae, regarding their load characteristics and failure modes in the case of heavy loading. The specimens were subjected to sequential axial cyclic loading of 5000cycles with stepwise increase of the load amplitude until failure. Migration of locking screws and internal damage of bone tissue was quantified by micro-computed tomography (CT) imaging. Ender nails failed on average at a peak load of 800 N, TwinPlugs at 1367 N, FixPlugs at 1222 N, Plugs 3.5mm at 1225 N and Plugs 3.0mm at 971 N. TwinPlugs, FixPlugs, and Plugs 3.5mm failed in a slow manner over several hundred loading cycles, whereas Ender nails and Plugs 3.0mm exhibited abrupt failure without any prior indication. Our results confirm that axial stability of FIN can be further improved by screw-fixed plugs by simultaneously avoiding shortcomings of an eye-locked system, which the Ender nails are. Considering biomechanical results, plug interlocking systems with 3.5-mm screws should be favored over conventional Ender nails and plugs with 3-mm screws. - Highlights: • Locked flexible intramedullary nails in lamb tibiae were cyclically loaded. • Strongly different failure modes of locking systems were detected. • Novel screw-fixed plugs are

  8. Mathematical foundations of elasticity

    CERN Document Server

    Marsden, Jerrold E

    1994-01-01

    This advanced-level study approaches mathematical foundations of three-dimensional elasticity using modern differential geometry and functional analysis. It is directed to mathematicians, engineers and physicists who wish to see this classical subject in a modern setting with examples of newer mathematical contributions. Prerequisites include a solid background in advanced calculus and the basics of geometry and functional analysis.The first two chapters cover the background geometry ― developed as needed ― and use this discussion to obtain the basic results on kinematics and dynamics of con

  9. Elastic and viscoplastic properties

    International Nuclear Information System (INIS)

    Lebensohn, R.A.

    2015-01-01

    In this chapter, we review crystal elasticity and plasticity-based self-consistent theories and apply them to the determination of the effective response of polycrystalline aggregates. These mean-field formulations, which enable the prediction of the mechanical behaviour of polycrystalline aggregates based on the heterogeneous and/or directional properties of their constituent single crystal grains and phases, are ideal tools to establish relationships between microstructure and properties of these materials, ubiquitous among fuels and structural materials for nuclear systems. (author)

  10. Performance Volatility and Wage Elasticity: An Examination of Listed Chinese A-share Enterprises

    Directory of Open Access Journals (Sweden)

    Donghua Chen

    2009-12-01

    Full Text Available The management of future financial risk on the part of managers and changes in firm finances are two of the fundamental reasons for upward and downward rigidity of wages. The proxy variable for firm financial risk is volatility, the past performance of which is among the principal indicators of wage rigidity. In firms whose current performance is on the upswing, the greater the volatility in past performance, the smaller the elasticity ratio and the more acute the upward rigidity; the more stable past performance, the larger the elasticity ratio and the more acute the upward elasticity. In firms in which current performance is declining, greater past performance volatility leads to a larger elasticity ratio and more acute downward rigidity, whereas more stable such performance leads to a smaller elasticity ratio and more acute downward rigidity.

  11. Mathematical methods in elasticity imaging

    CERN Document Server

    Ammari, Habib; Garnier, Josselin; Kang, Hyeonbae; Lee, Hyundae; Wahab, Abdul

    2015-01-01

    This book is the first to comprehensively explore elasticity imaging and examines recent, important developments in asymptotic imaging, modeling, and analysis of deterministic and stochastic elastic wave propagation phenomena. It derives the best possible functional images for small inclusions and cracks within the context of stability and resolution, and introduces a topological derivative-based imaging framework for detecting elastic inclusions in the time-harmonic regime. For imaging extended elastic inclusions, accurate optimal control methodologies are designed and the effects of uncertainties of the geometric or physical parameters on stability and resolution properties are evaluated. In particular, the book shows how localized damage to a mechanical structure affects its dynamic characteristics, and how measured eigenparameters are linked to elastic inclusion or crack location, orientation, and size. Demonstrating a novel method for identifying, locating, and estimating inclusions and cracks in elastic...

  12. Elastic emission polishing

    Energy Technology Data Exchange (ETDEWEB)

    Loewenthal, M.; Loseke, K.; Dow, T.A.; Scattergood, R.O.

    1988-12-01

    Elastic emission polishing, also called elastic emission machining (EEM), is a process where a stream of abrasive slurry is used to remove material from a substrate and produce damage free surfaces with controlled surface form. It is a noncontacting method utilizing a thick elasto-hydrodynamic film formed between a soft rotating ball and the workpiece to control the flow of the abrasive. An apparatus was built in the Center, which consists of a stationary spindle, a two-axis table for the workpiece, and a pump to circulate the working fluid. The process is controlled by a programmable computer numerical controller (CNC), which presently can operate the spindle speed and movement of the workpiece in one axis only. This apparatus has been used to determine material removal rates on different material samples as a function of time, utilizing zirconium oxide (ZrO{sub 2}) particles suspended in distilled water as the working fluid. By continuing a study of removal rates the process should become predictable, and thus create a new, effective, yet simple tool for ultra-precision mechanical machining of surfaces.

  13. Heavy ion elastic scatterings

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1984-01-01

    Diffraction and refraction play an important role in particle elastic scattering. The optical model treats correctly and simultaneously both phenomena but without disentangling them. Semi-classical discussions in terms of trajectories emphasize the refractive aspect due to the real part of the optical potential. The separation due to to R.C. Fuller of the quantal cross section into two components coming from opposite side of the target nucleus allows to understand better the refractive phenomenon and the origin of the observed oscillations in the elastic scattering angular distributions. We shall see that the real part of the potential is responsible of a Coulomb and a nuclear rainbow which allows to determine better the nuclear potential in the interior region near the nuclear surface since the volume absorption eliminates any effect of the real part of the potential for the internal partial scattering waves. Resonance phenomena seen in heavy ion scattering will be discussed in terms of optical model potential and Regge pole analysis. Compound nucleus resonances or quasi-molecular states can be indeed the more correct and fundamental alternative

  14. Design guidance for elastic followup

    International Nuclear Information System (INIS)

    Naugle, F.V.

    1983-01-01

    The basic mechanism of elastic followup is discussed in relation to piping design. It is shown how mechanistic insight gained from solutions for a two-bar problem can be used to identify dominant design parameters and to determine appropriate modifications where elastic followup is a potential problem. It is generally recognized that quantitative criteria are needed for elastic followup in the creep range where badly unbalanced lines can pose potential problems. Approaches for criteria development are discussed

  15. Income Elasticity of Environmental Amenities

    OpenAIRE

    Daniel Miles; Andrés Pereyra; Máximo Rossi

    2000-01-01

    In this paper we are concerned with the estimation of income elasticities of environmental amenities. The novelty is the application of econometric methods that take into account the problem of measurement errors when estimating these elasticities, which are common in microeconomic data and are not usually considered in the applied literature related with this issue. Our aim is to discuss whether the measurement error has signi…cant e¤ects on the elasticities. Data from the Expenditure Budget...

  16. Position calibration of silicon strip detector using quasi-elastic scattering of 16O+197Au

    International Nuclear Information System (INIS)

    Yan Wenqi; Hu Hailong; Zhang Gaolong

    2013-01-01

    Background: Elastic scattering is induced by weakly unstable nuclei. Generally, a good angular resolution for angular distribution of elastic scattering is needed. The silicon strip detector is often used for this kind of experiment. Purpose: In order to use silicon strip detector to study the elastic scattering of weakly unbound nuclei, it is important to get the information of its position calibration. It is well known that the elastic scattering of stable nuclei has a good angular distribution and many experimental data have been obtained. Methods: So the scattering of stable nuclei can be used to calibrate the position information of silicon strip detector. In this experiment, the positions of silicon strip detectors are calibrated using 101 MeV and 59 MeV 16 O scattering on the 197 Au target. Results: The quasi-elastic peaks can be observed in the silicon strip detectors and the counts of quasi-elastic 16 O can be obtained. The solid angles of the silicon strip detectors are calibrated by using alpha source which has three alpha energy values. The angular distribution of quasi-elastic scattering of 16 O+ 197 Au is obtained at these two energy values. Conclusions: The experimental data of angular distribution are reasonable and fit for the principle of angular distribution of elastic scattering. It is concluded that in the experiment these silicon strip detectors can accurately give the position information and can be used for the elastic scattering experiment. (authors)

  17. A Midterm Review of Lesser Toe Arthrodesis With an Intramedullary Implant.

    Science.gov (United States)

    Harmer, James Lee; Wilkinson, Anthony; Maher, Anthony John

    2017-10-01

    Lesser toe deformities are one of the most common conditions encountered by podiatric surgeons. When conservative treatments fail surgical correction is indicated. Many surgical options have been described to address the complex nature of these deformities but no perfect solution has been reported to date. However, with the continued advancement of internal fixation technology, interphalangeal joint (IPJ) arthrodesis with an intramedullary implant may be a good option. This retrospective study presents patient reported outcomes and complications at 6 months and 3 years following lesser toe proximal interphalangeal joint (PIPJ) arthrodesis with a polyketone intrameduallary implant (Toe Grip, Orthosolutions, UK). Between September 2011 and November 2012, a total of 38 patients attended for second toe PIPJ arthrodesis by means of the Toe Grip device. At 6 months postoperation, 94.7% of patients and at 3 years postoperation, 92.8% of patients felt that their original complaint was better or much better. Health-related quality of life scores continued to improve overtime as measured by the Manchester Oxford Foot Questionnaire. Complications were generally observational and asymptomatic. The most common complications were floating toes (17.8%), mallet deformities (14.2%), metatarsalgia (17.8%), and transverse plane deformity of the toe (10.7%). This study demonstrates excellent patient-eported outcomes with minimal symptomatic complications making the "Toe Grip" implant a safe and effective alternative fixation device for IPJ arthrodesis when dealing with painful digital deformities. Therapeutic, Level IV: Case series.

  18. Effects of a telescopic intramedullary rod for treating patients with osteogenesis imperfecta of the femur

    Science.gov (United States)

    Rosemberg, D. L.; Goiano, E. O.; Akkari, M.; Santili, C.

    2018-01-01

    Abstract Purpose To introduce a new model of telescopic intramedullary rod (TIR), evaluate its effects on treating patients presenting with moderate and severe osteogenesis imperfecta (OI) and to compare the findings with those of other telescopic rods. Methods A total of 21 patients (nine girls and 12 boys; mean age at first operation, 6.6 years, 1.52 to 13.18) who underwent 52 femoral operations were monitored during a mean of 9.96 years (3.39 to 14.54). Patient characteristics, telescoping rod capability and its complications were examined. Results According to the Sillence classification, we investigated one patient with type I, nine with type III and 11 with type IV OI. Revision rates at up to five years (36%) were inferior to those found for the Fassier-Duval rod (46%). The main cause of revision was fracture (15 patients), followed by rod migration (nine), and infection (two). The rod exhibited higher telescopic capacity in boys than girls. Type III most commonly required an operation; the age group with the highest number of procedures was five to ten years. Male migration was the main cause of rod migration. Conclusion The TIR has a satisfactory cost-benefit ratio with less complication rates and low production costs. The TIR is a feasible alternative to the commonly used Fassier-Duval rod. Level of Evidence IV PMID:29456761

  19. Segmental transport after unreamed intramedullary nailing. Preliminary report of a "Monorail" system.

    Science.gov (United States)

    Raschke, M J; Mann, J W; Oedekoven, G; Claudi, B F

    1992-09-01

    The Ilizarov method of segmental bone transport has been shown to be an alternative to more conventional treatments of posttraumatic bony defects. After extensive clinical experience with the unreamed tibial nail in open fractures up to Grade IIIb, a new monorail fixation system for callus distraction and segmental bone transport was devised. This Monorail system is composed of an unreamed intramedullary (IM) nail and a unilateral AO distraction device. The new fixation method and the preliminary clinical experience are reported here. Four patients who previously sustained Grades II-IIIb open tibial fractures had an average bony defect of 9 cm. Two patients had previous bony infections. All patients had had serial debridements and myocutaneous flaps were required in three patients. An unreamed IM nail was inserted, and the transport device was applied. After an osteotomy, segmental transport was carried out until docking was achieved. The external fixator was removed after interlocking of the transported segment. The mean duration of external fixation was 17.9 days/cm and the mean period until roentgenographic consolidation of the distraction and nonunion site was 41.2 days/cm. There were two pin-tract infections but no IM infections. One nail broke after osseous consolidation of the regenerate at the distal interlocking site and required exchange. The goal of transport was achieved in all cases without angular or rotational deformity or length discrepancy. There were no neurovascular injuries.

  20. Intraosseous migration of tendinous calcifications: cortical erosions, subcortical migration and extensive intramedullary diffusion, a SIMS series

    Energy Technology Data Exchange (ETDEWEB)

    Malghem, Jacques; Omoumi, Patrick; Lecouvet, Frederic; Berg, Bruno vande [Universite Catholique de Louvain, Departement de radiologie et d' imagerie medicale, Bruxelles (Belgium)

    2015-10-15

    Calcium hydroxyapatite crystal deposition is a common disorder, which sometimes causes acute pain as calcifications dissolve and migrate into adjacent soft tissue. Intraosseous calcium penetration has also been described. We illustrate the appearance of these lesions using a series of 35 cases compiled by members of the French Society of Musculoskeletal Imaging (Societe d'Imagerie Musculo-Squelettique, SIMS). The first group in our series (7 cases) involved calcification-related cortical erosions of the humeral and femoral diaphyses, in particular at the pectoralis major and gluteus maximus insertions. A second group (28 cases) involved the presence of calcium material in subcortical areas. The most common site was the greater tubercle of the humerus, accompanying a calcifying tendinopathy of the supraspinatus. In addition, an extensive intramedullary diffusion of calcium deposits was observed in four of these cases, associated with cortical erosion in one case and subcortical lesions in three cases. Cortical erosions and intraosseous migration of calcifications associated with calcific tendinitis may be confused with neoplasm or infection. It is important to recognize atypical presentations of hydroxyapatite deposition to avoid unnecessary investigation or surgery. (orig.)

  1. Shielding of the patient's gonads during intramedullary interlocking femoral nailing

    Energy Technology Data Exchange (ETDEWEB)

    Kwong, L.M.; Johanson, P.H.; Zinar, D.M.; Lenihan, M.R.; Herman, M.W. (Harbor/Univ. of California, Los Angeles Medical Center, Torrance (USA))

    1990-12-01

    Levels of exposure to radiation were recorded at sixty sites in fifteen patients during intramedullary interlocking femoral nailing. Radiation film dosimeters were placed at four gonadal sites on each subject. A standard male-gonad cup or a pelvic drape of 0.5-millimeter-thick lead-equivalent was put in place to shield the gonads. A second set of four dosimeters was placed external to the shield to approximate unprotected exposure. The total duration of the fluoroscopy averaged five minutes (range, thirty seconds to fourteen minutes). The total exposure to radiation external to the shield was 35 +/- 34 millirems at the male gonadal sites and 17 +/- 11 millirems at the female gonadal sites. With use of the gonadal shield, exposure to radiation was not measurable in thirteen of the fifteen patients. The differences between the exposures of the shielded and unshielded sites to radiation were statistically significant (p less than 0.001). The highest level of gonadal exposure was found with the treatment of proximal femoral fractures and with the use of statically locked nails. Regardless of the conditions, and for all types of fractures and locations, our results demonstrated that gonadal shielding is justified.

  2. A novel smart navigation system for intramedullary nailing in orthopedic surgery.

    Directory of Open Access Journals (Sweden)

    Jaesuk Choi

    Full Text Available This paper proposes a novel smart surgical navigation system for intramedullary nailing in orthopedic surgery. Using a handle-integrated laser guidance module, the system can target a drill insertion point onto skin, indicating an accurate target position to perpendicularly access an invisible distal hole. The proposed handle-integration-based fixation of the laser guidance module precisely defines the relative position of the module with respect to the distal hole. Consequently, unlike conventional systems, the proposed system can indicate the target insertion point without any help from bulky and costly external position-tracking equipment that is usually required for compensating disturbances generated by external impacts. After insertion, a correct drilling direction toward the distal hole is guided by real-time drilling angle measurement modules-one integrated with the nail handle and the other with the drill body. Each module contains a 9-axis inertial sensor and a Bluetooth communication device. These two modules work together to provide real-time drilling angle data, allowing calculation of the directional error toward the center of the distal hole in real time. The proposed system removes the need for fluoroscopy and provides a compact and cost-effective solution compared with conventional systems.

  3. stableGP

    Data.gov (United States)

    National Aeronautics and Space Administration — The code in the stableGP package implements Gaussian process calculations using efficient and numerically stable algorithms. Description of the algorithms is in the...

  4. Angina Pectoris (Stable Angina)

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Angina Pectoris (Stable Angina) Updated:Aug 21,2017 You may have heard the term “angina pectoris” or “stable angina” in your doctor’s office, ...

  5. Questions about elastic waves

    CERN Document Server

    Engelbrecht, Jüri

    2015-01-01

    This book addresses the modelling of mechanical waves by asking the right questions about them and trying to find suitable answers. The questions follow the analytical sequence from elementary understandings to complicated cases, following a step-by-step path towards increased knowledge. The focus is on waves in elastic solids, although some examples also concern non-conservative cases for the sake of completeness. Special attention is paid to the understanding of the influence of microstructure, nonlinearity and internal variables in continua. With the help of many mathematical models for describing waves, physical phenomena concerning wave dispersion, nonlinear effects, emergence of solitary waves, scales and hierarchies of waves as well as the governing physical parameters are analysed. Also, the energy balance in waves and non-conservative models with energy influx are discussed. Finally, all answers are interwoven into the canvas of complexity.

  6. Nonlinear Elasticity of Doped Semiconductors

    Science.gov (United States)

    2017-02-01

    AFRL-RY-WP-TR-2016-0206 NONLINEAR ELASTICITY OF DOPED SEMICONDUCTORS Mark Dykman and Kirill Moskovtsev Michigan State University...2016 4. TITLE AND SUBTITLE NONLINEAR ELASTICITY OF DOPED SEMICONDUCTORS 5a. CONTRACT NUMBER FA8650-16-1-7600 5b. GRANT NUMBER 5c. PROGRAM...vibration amplitude. 15. SUBJECT TERMS semiconductors , microresonators, microelectromechanical 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  7. Elasticity theory of ultrathin nanofilms

    International Nuclear Information System (INIS)

    Li, Jiangang; Yun, Guohong; Narsu, B; Yao, Haiyan

    2015-01-01

    A self-consistent theoretical scheme for describing the elastic behavior of ultrathin nanofilms (UTNFs) was proposed. Taking into account the lower symmetry of an UTNF compared to its bulk counterpart, additional elastic and magnetoelastic parameters were introduced to model the elasticity rigorously. The applications of current theory to several elastic and magnetoelastic systems gave excellent agreement with experiments. More importantly, the surface elastic and magnetoelastic parameters used to fit the experimental results are physically reasonable and in close agreement with those obtained from experiment and simulation. This fact suggests that the additional elastic (magnetoelastic) constants due to symmetry breaking are of great importance in theoretical description of the mechanical properties of UTNFs. And we proved that the elasticity of UTNFs should be described by a three-dimensional model just including the intrinsic surface and bulk parameters, but not the effective surface parameters. It is believed that the theory reported here is a universal strategy for elasticity and magnetoelasticity of ultrathin films. (paper)

  8. Cell Elasticity Determines Macrophage Function

    Science.gov (United States)

    Patel, Naimish R.; Bole, Medhavi; Chen, Cheng; Hardin, Charles C.; Kho, Alvin T.; Mih, Justin; Deng, Linhong; Butler, James; Tschumperlin, Daniel; Fredberg, Jeffrey J.; Krishnan, Ramaswamy; Koziel, Henry

    2012-01-01

    Macrophages serve to maintain organ homeostasis in response to challenges from injury, inflammation, malignancy, particulate exposure, or infection. Until now, receptor ligation has been understood as being the central mechanism that regulates macrophage function. Using macrophages of different origins and species, we report that macrophage elasticity is a major determinant of innate macrophage function. Macrophage elasticity is modulated not only by classical biologic activators such as LPS and IFN-γ, but to an equal extent by substrate rigidity and substrate stretch. Macrophage elasticity is dependent upon actin polymerization and small rhoGTPase activation, but functional effects of elasticity are not predicted by examination of gene expression profiles alone. Taken together, these data demonstrate an unanticipated role for cell elasticity as a common pathway by which mechanical and biologic factors determine macrophage function. PMID:23028423

  9. Cell elasticity determines macrophage function.

    Directory of Open Access Journals (Sweden)

    Naimish R Patel

    Full Text Available Macrophages serve to maintain organ homeostasis in response to challenges from injury, inflammation, malignancy, particulate exposure, or infection. Until now, receptor ligation has been understood as being the central mechanism that regulates macrophage function. Using macrophages of different origins and species, we report that macrophage elasticity is a major determinant of innate macrophage function. Macrophage elasticity is modulated not only by classical biologic activators such as LPS and IFN-γ, but to an equal extent by substrate rigidity and substrate stretch. Macrophage elasticity is dependent upon actin polymerization and small rhoGTPase activation, but functional effects of elasticity are not predicted by examination of gene expression profiles alone. Taken together, these data demonstrate an unanticipated role for cell elasticity as a common pathway by which mechanical and biologic factors determine macrophage function.

  10. Multipurpose hooks for elastic attachment

    Directory of Open Access Journals (Sweden)

    Siddharth Shashidhar Revankar

    2014-01-01

    Full Text Available As certain bracket systems do not include hooks on premolar brackets for elastic attachment, Kobayashi or custom made ligature hooks have proven as an alternative. However, these hooks tend to bend labially when used with heavy elastics and these elastics can even pop loose from the hooks on mouth opening. The following article describes an innovative multipurpose hook which is simple, stiff and inexpensive and can be used for engagement of class II elastics on premolars in case of missing molars as well as engagement of intermaxillary elastics for settling of occlusion in finishing stages. As the hooks can be prefabricated, this saves a lot of chair side time and is more practical for use in day-to-day orthodontic practice.

  11. Occurrence of secondary fracture around intramedullary nails used for trochanteric hip fractures: a systematic review of 13,568 patients.

    Science.gov (United States)

    Norris, Rory; Bhattacharjee, Dhritiman; Parker, Martyn J

    2012-06-01

    A sliding hip screw (SHS) is currently the treatment of choice for trochanteric hip fractures, largely due to the low incidence of complications. An alternative treatment is the use of intramedullary proximal femoral nails. Unfortunately these implants have been associated with a risk of later fracture around the implant. The aim of this study was to see if any improvements have been made to the current intramedullary nails, to reduce the incidence of secondary fracture around the distal tip of the nail. We analysed data related to 13,568 patients from 89 studies, focusing on the incidence of post operative secondary femoral shaft fracture following the use of intramedullary nails in the fixation of trochanteric hip fractures. The overall reported incidence of secondary fracture around the nail was 1.7%. The incidence of fracture has reduced in the 3rd generation Gamma nails when compared to the older Gamma nail (1.7% versus 2.6%, p value 0.03). However, the incidence of secondary fracture in the 3rd generation Gamma nails is still significantly higher than the other brands of short nail (1.7% versus 0.7%, p value 0.0005). Long nails had a slight tendency towards a lower risk of fracture although the difference was not statistically significant (1.1% versus 1.7%, p value 0.28). There was a significantly lower risk of fracture for those nails with a biaxial fixation as opposed to uniaxial fixation (0.6% versus 1.9%, p value fracture around a proximal femoral nail is one of the most significant of fracture healing complications, and this study suggests that continuing design changes to this method of fixation has reduced the risk of this complication occurring. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Blocky inversion of multichannel elastic impedance for elastic parameters

    Science.gov (United States)

    Mozayan, Davoud Karami; Gholami, Ali; Siahkoohi, Hamid Reza

    2018-04-01

    Petrophysical description of reservoirs requires proper knowledge of elastic parameters like P- and S-wave velocities (Vp and Vs) and density (ρ), which can be retrieved from pre-stack seismic data using the concept of elastic impedance (EI). We propose an inversion algorithm which recovers elastic parameters from pre-stack seismic data in two sequential steps. In the first step, using the multichannel blind seismic inversion method (exploited recently for recovering acoustic impedance from post-stack seismic data), high-resolution blocky EI models are obtained directly from partial angle-stacks. Using an efficient total-variation (TV) regularization, each angle-stack is inverted independently in a multichannel form without prior knowledge of the corresponding wavelet. The second step involves inversion of the resulting EI models for elastic parameters. Mathematically, under some assumptions, the EI's are linearly described by the elastic parameters in the logarithm domain. Thus a linear weighted least squares inversion is employed to perform this step. Accuracy of the concept of elastic impedance in predicting reflection coefficients at low and high angles of incidence is compared with that of exact Zoeppritz elastic impedance and the role of low frequency content in the problem is discussed. The performance of the proposed inversion method is tested using synthetic 2D data sets obtained from the Marmousi model and also 2D field data sets. The results confirm the efficiency and accuracy of the proposed method for inversion of pre-stack seismic data.

  14. Sequential Magnetic Resonance Imaging Finding of Intramedullary Spinal Cord Abscess including Diffusion Weighted Image: a Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Jae Eun; Lee, Seung Young; Cha, Sang Hoon; Cho, Bum Sang; Jeon, Min Hee; Kang, Min Ho [Chungbuk National University College of Medicine, Cheongju (Korea, Republic of)

    2011-04-15

    Intramedullary spinal cord abscess (ISCA) is a rare infection of the central nervous system. We describe the magnetic resonance imaging (MRI) findings, including the diffusion-weighted imaging (DWI) findings, of ISCA in a 78-year-old man. The initial conventional MRI of the thoracic spine demonstrated a subtle enhancing nodule accompanied by significant edema. On the follow-up MRI after seven days, the nodule appeared as a ring-enhancing nodule. The non-enhancing central portion of the nodule appeared hyperintense on DWI with a decreased apparent diffusion coefficient (ADC) value on the ADC map. We performed myelotomy and surgical drainage, and thick, yellowish pus was drained

  15. Mechanical Properties of Stable Glasses Using Nanoindentation

    Science.gov (United States)

    Wolf, Sarah; Liu, Tianyi; Jiang, Yijie; Ablajan, Keyume; Zhang, Yue; Walsh, Patrick; Turner, Kevin; Fakhraai, Zahra

    Glasses with enhanced stability over ordinary, liquid quenched glasses have been formed via the process of Physical Vapor Deposition (PVD) by using a sufficiently slow deposition rate and a substrate temperature slightly below the glass transition temperature. These stable glasses have been shown to exhibit higher density, lower enthalpy, and better kinetic stability over ordinary glass, and are typically optically birefringent, due to packing and orientational anisotropy. Given these exceptional properties, it is of interest to further investigate how the properties of stable glasses compare to those of ordinary glass. In particular, the mechanical properties of stable glasses remain relatively under-investigated. While the speed of sound and elastic moduli have been shown to increase with increased stability, little is known about their hardness and fracture toughness compared to ordinary glasses. In this study, glasses of 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene were deposited at varying temperatures relative to their glass transition temperature, and their mechanical properties measured by nanoindentation. Hardness and elastic modulus of the glasses were compared across substrate temperatures. After indentation, the topography of these films were studied using Atomic Force Microscopy (AFM) in order to further compare the relationship between thermodynamic and kinetic stability and mechanical failure. Z.F. and P.W. acknowledge funding from NSF(DMREF-1628407).

  16. Reamed intramedullary exchange nailing in the operative treatment of aseptic tibial shaft nonunion.

    Science.gov (United States)

    Hierholzer, Christian; Friederichs, Jan; Glowalla, Claudio; Woltmann, Alexander; Bühren, Volker; von Rüden, Christian

    2017-08-01

    The aim of this study was to evaluate a standardized treatment protocol regarding the rate of secondary bone union, complications, and functional outcome. This study was started as a prospective study in a single Level I Trauma Centre between 2003 and 2012. The study group consisted of 188 patients with the diagnosis of an aseptic tibial shaft nonunion. Exchange nailing was performed following a standardized surgical protocol. Long-term follow-up was analyzed for rate of bone healing and functional outcome. Osseous healing was achieved in 182 out of 188 patients (97 %). In 165 out of 188 patients (88 %), bone healing was observed timely and uneventfully after a single exchange nailing procedure. An open approach was necessary in 32 patients (17 %). Twenty-three patients (12 %) required additional therapy such as extracorporeal shock wave therapy. Post-operative complications were observed in seven patients (4 %). Almost all patients demonstrated osseous healing within 12 months, with the majority of osseous healing occurring within six months. A relevant shortening of the fractured tibia was observed in 20 out of 188 patients (11 %). After a median follow-up of 23 months (range 12-45 months), outcome was evaluated using the assessment system of Friedman/Wyman. In summary, 154 out of 188 patients (82 %) had a good functional long-term result. Reamed intramedullary exchange nailing including correction of axis alignment is a safe and effective treatment of aseptic tibial shaft nonunion with a high rate of bone healing and a good radiological and functional long-term outcome.

  17. Ipsilateral proximal femur and shaft fractures treated with hip screws and a reamed retrograde intramedullary nail.

    Science.gov (United States)

    Ostrum, Robert F; Tornetta, Paul; Watson, J Tracy; Christiano, Anthony; Vafek, Emily

    2014-09-01

    Although not common, proximal femoral fractures associated with ipsilateral shaft fractures present a difficult management problem. A variety of surgical options have been employed with varying results. We investigated the use of hip screws and a reamed retrograde intramedullary (IM) nail for the treatment of this combined fracture pattern in terms of postoperative alignment (malunion), nonunion, and complications. Between May 2002 and October 2011, a total of 95 proximal femoral fractures with associated shaft fractures were treated at three participating Level 1 trauma centers; all were treated with hip screw fixation (cannulated screws or sliding hip screws) and retrograde reamed IM nails. The medical records of these patients were reviewed retrospectively for alignment, malunion, nonunion, and complications. Followup was available on 92 of 95 (97%) of the patients treated with hip screws and a retrograde nail. Forty were treated with a sliding hip screw, and 52 were treated with cannulated screws. There were five proximal malunions in this series (5%). The union rate was 98% (90 of 92) for the femoral neck fractures and 91.3% (84 of 92) for the femoral shaft fractures after the initial surgery. There were two nonunions of comminuted femoral neck fractures after cannulated screw fixation. There was no difference in femoral neck union or alignment when comparing cannulated screws to a sliding hip screw. Four open comminuted femoral shaft fractures went on to nonunion and required secondary surgery to obtain union, and one patient developed symptomatic avascular necrosis. The treatment of ipsilateral proximal femoral neck and shaft fractures with hip screw fixation and a reamed retrograde nail demonstrated a high likelihood of union for the femoral neck fractures and a low risk of malunion. Comminution and initial displacement of the proximal femoral fracture may still lead to a small incidence of malunion or nonunion, and open comminuted femoral shaft fractures

  18. Outcome predictors in the management of intramedullary classic ependymoma: An integrative survival analysis.

    Science.gov (United States)

    Wang, Yinqing; Cai, Ranze; Wang, Rui; Wang, Chunhua; Chen, Chunmei

    2018-06-01

    This is a retrospective study.The aim of this study was to illustrate the survival outcomes of patients with classic ependymoma (CE) and identify potential prognostic factors.CE is the most common category of spinal ependymomas, but few published studies have discussed predictors of the survival outcome.A Boolean search of the PubMed, Embase, and OVID databases was conducted by 2 investigators independently. The objects were intramedullary grade II ependymoma according to 2007 WHO classification. Univariate Kaplan-Meier analysis and Log-Rank tests were performed to identify variables associated with progression-free survival (PFS) or overall survival (OS). Multivariate Cox regression was performed to assess hazard ratios (HRs) with 95% confidence intervals (95% CIs). Statistical analysis was performed by SPSS version 23.0 (IBM Corp.) with statistical significance defined as P analysis showed that patients who had undergone total resection (TR) had better PFS and OS than those with subtotal resection (STR) and biopsy (P = .002, P = .004, respectively). Within either univariate or multivariate analysis (P = .000, P = .07, respectively), histological type was an independent prognostic factor for PFS of CE [papillary type: HR 0.002, 95% CI (0.000-0.073), P = .001, tanycytic type: HR 0.010, 95% CI (0.000-0.218), P = .003].It was the first integrative analysis of CE to elucidate the correlation between kinds of factors and prognostic outcomes. Definite histological type and safely TR were foundation of CE's management. 4.

  19. Effect of Pentoxifylline Administration on an Experimental Rat Model of Femur Fracture Healing With Intramedullary Fixation.

    Science.gov (United States)

    Vashghani Farahani, Mohammad Mahdi; Masteri Farahani, Reza; Mostafavinia, Ataroalsadat; Abbasian, Mohammad Reza; Pouriran, Ramin; Noruzian, Mohammad; Ghoreishi, Seyed Kamran; Aryan, Arefe; Bayat, Mohammad

    2015-12-01

    Globally, musculoskeletal injuries comprise a major public health problem that contributes to a large burden of disability and suffering. Pentoxifylline (PTX) has been originally used as a hemorheologic drug to treat intermittent claudication. Previous test tube and in vivo studies reported the beneficial effects of PTX on bony tissue. This study aims to evaluate the effects of different dosages of PTX on biomechanical properties that occur during the late phase of the fracture healing process following a complete femoral osteotomy in a rat model. We applied intramedullary pin fixation as the treatment of choice. This experimental study was conducted at the Shahid Beheshti University of Medical Sciences, Tehran, Iran. We used the simple random technique to divide 35 female rats into five groups. Group 1 received intraperitoneal (i.p.) PTX (50 mg/kg, once daily) injections, starting 15 days before surgery, and group 2, group 3, and group 4 received 50 mg/kg, 100 mg/kg, and 200 mg/kg i.p. PTX injections, respectively, once daily after surgery. All animals across groups received treatment for six weeks (until sacrificed). Complete surgical transverse osteotomy was performed in the right femur of all rats. At six weeks after surgery, the femurs were subjected to a three-point bending test. Daily administration of 50 mg/kg PTX (groups 1 and 2) decreased the high stress load in repairing osteotomized femurs when compared with the control group. The highest dose of PTX (200 mg/kg) significantly increased the high stress load when compared with the control group (P = 0.030), group 1 (P = 0.023), group 2 (P = 0.008), and group 3 (P = 0.010), per the LSD findings. Treatment with 200 mg/kg PTX accelerated fracture healing when compared with the control group.

  20. Radiographic study of the fifth metatarsal for optimal intramedullary screw fixation of Jones fracture.

    Science.gov (United States)

    Ochenjele, George; Ho, Bryant; Switaj, Paul J; Fuchs, Daniel; Goyal, Nitin; Kadakia, Anish R

    2015-03-01

    Jones fractures occur in the relatively avascular metadiaphyseal junction of the fifth metatarsal (MT), which predisposes these fractures to delayed union and nonunion. Operative treatment with intramedullary (IM) screw fixation is recommended in certain cases. Incorrect screw selection can lead to refractures, nonunion, and cortical blowout fractures. A better understanding of the anatomy of the fifth MT could aid in preoperative planning, guide screw size selection, and minimize complications. We retrospectively identified foot computed tomographic (CT) scans of 119 patients that met inclusion criteria. Using interactive 3-dimensional (3-D) models, the following measurements were calculated: MT length, "straight segment length" (distance from the base of the MT to the shaft curvature), and canal diameter. The diaphysis had a lateroplantar curvature where the medullary canal began to taper. The average straight segment length was 52 mm, and corresponded to 68% of the overall length of the MT from its proximal end. The medullary canal cross-section was elliptical rather than circular, with widest width in the sagittal plane and narrowest in coronal plane. The average coronal canal diameter at the isthmus was 5.0 mm. A coronal diameter greater than 4.5 mm at the isthmus was present in 81% of males and 74% of females. To our knowledge, this is the first anatomic description of the fifth metatarsal based on 3-D imaging. Excessive screw length could be avoided by keeping screw length less than 68% of the length of the fifth metatarsal. A greater than 4.5 mm diameter screw might be needed to provide adequate fixation for most study patients since the isthmus of the medullary canal for most were greater than 4.5 mm. Our results provide an improved understanding of the fifth metatarsal anatomy to guide screw diameter and length selection to maximize screw fixation and minimize complications. © The Author(s) 2014.

  1. Rotational malalignment after closed intramedullary nailing of femoral shaft fractures and its influence on daily life.

    Science.gov (United States)

    Karaman, Ozgur; Ayhan, Egemen; Kesmezacar, Hayrettin; Seker, Ali; Unlu, Mehmet Can; Aydingoz, Onder

    2014-10-01

    Any intraoperative rotational malalignment during intramedullary nailing (IMN) of femoral shaft fractures will become permanent. We hypothesized that rotational malalignment of the femur and its compensatory biomechanics may induce problems in the hip, knee, patellofemoral and ankle joints. We purposed to clarify the influence of a femoral rotational malalignment of ≥10° on daily activities. Twenty-four femoral shaft fracture patients treated with closed antegrade IMN were included. At last follow-up, to reveal any rotational malalignment, computerized tomography (CT) scans of both femurs (injured and uninjured sides) were examined. The patient groups with or without CT-detected true rotational malalignment ≥10° were compared with respect to the activity scores. Ten of the 24 patients (41.7%) had a CT-detected true rotational malalignment of ≥10° compared with the unaffected side. The AOFAS scores were 100.00 for all of the patients. LKS, WOMAC knee, and WOMAC hip scores were significantly decreased in the patients with rotational malalignment compared to those without. Patients without rotational malalignment tolerated climbing stairs significantly better than those with rotational malalignment. Patients who could not tolerate climbing stairs were consistently complaining of anterior knee pain. A femoral rotational malalignment of ≥10° is symptomatic for the patients, and the hip, knee, and patellofemoral joints were affected. Because of the possibly altered joint loadings and biomechanics, these could render patients prone to degenerative joint disease. In addition, due to the high rates of rotational malalignment after femoral shaft fracture and consequent malpractice claims, it is important for surgeons to be more aware of rotational alignment during surgery.

  2. Skeletal nutrient vascular adaptation induced by external oscillatory intramedullary fluid pressure intervention

    Directory of Open Access Journals (Sweden)

    Qin Yi-Xian

    2010-03-01

    Full Text Available Abstract Background Interstitial fluid flow induced by loading has demonstrated to be an important mediator for regulating bone mass and morphology. It is shown that the fluid movement generated by the intramedullary pressure (ImP provides a source for pressure gradient in bone. Such dynamic ImP may alter the blood flow within nutrient vessel adjacent to bone and directly connected to the marrow cavity, further initiating nutrient vessel adaptation. It is hypothesized that oscillatory ImP can mediate the blood flow in the skeletal nutrient vessels and trigger vasculature remodeling. The objective of this study was then to evaluate the vasculature remodeling induced by dynamic ImP stimulation as a function of ImP frequency. Methods Using an avian model, dynamics physiological fluid ImP (70 mmHg, peak-peak was applied in the marrow cavity of the left ulna at either 3 Hz or 30 Hz, 10 minutes/day, 5 days/week for 3 or 4 weeks. The histomorphometric measurements of the principal nutrient arteries were done to quantify the arterial wall area, lumen area, wall thickness, and smooth muscle cell layer numbers for comparison. Results The preliminary results indicated that the acute cyclic ImP stimuli can significantly enlarge the nutrient arterial wall area up to 50%, wall thickness up to 20%, and smooth muscle cell layer numbers up to 37%. In addition, 3-week of acute stimulation was sufficient to alter the arterial structural properties, i.e., increase of arterial wall area, whereas 4-week of loading showed only minimal changes regardless of the loading frequency. Conclusions These data indicate a potential mechanism in the interrelationship between vasculature adaptation and applied ImP alteration. Acute ImP could possibly initiate the remodeling in the bone nutrient vasculature, which may ultimately alter blood supply to bone.

  3. Robust identification and localization of intramedullary nail holes for distal locking using CBCT: a simulation study.

    Science.gov (United States)

    Kamarianakis, Z; Buliev, I; Pallikarakis, N

    2011-05-01

    Closed intramedullary nailing is a common technique for treatment of femur and tibia fractures. The most challenging step in this procedure is the precise placement of the lateral screws that stabilize the fragmented bone. The present work concerns the development and the evaluation of a method to accurately identify in the 3D space the axes of the nail hole canals. A limited number of projection images are acquired around the leg with the help of a C-arm. On two of them, the locking hole entries are interactively selected and a rough localization of the hole axes is performed. Perpendicularly to one of them, cone-beam computed tomography (CBCT) reconstructions are produced. The accurate identification and localization of the hole axes are done by an identification of the centers of the nail holes on the tomograms and a further 3D linear regression through principal component analysis (PCA). Various feature-based approaches (RANSAC, least-square fitting, Hough transform) have been compared for best matching the contours and the centers of the holes on the tomograms. The robustness of the suggested method was investigated using simulations. Programming is done in Matlab and C++. Results obtained on synthetic data confirm very good localization accuracy - mean translational error of 0.14 mm (std=0.08 mm) and mean angular error of 0.84° (std=0.35°) at no radiation excess. Successful localization can be further used to guide a surgeon or a robot for correct drilling the bone along the nail openings. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.

  4. Elastic Anisotropy of Basalt

    Science.gov (United States)

    Becker, K.; Shapiro, S.; Stanchits, S.; Dresen, G.; Kaselow, A.; Vinciguerra, S.

    2005-12-01

    Elastic properties of rocks are sensitive to changes of the in-situ stress and damage state. In particular, seismic velocities are strongly affected by stress-induced formation and deformation of cracks or shear-enhanced pore collapse. The effect of stress on seismic velocities as a result of pore space deformation in isotropic rock at isostatic compression may be expressed by the equation: A+K*P-B*exp (-D*P) (1), where P=Pc-Pp is the effective pressure, the pure difference between confining pressure and pore pressure. The parameter A, K, B and D describe material constants determined using experimental data. The physical meaning of the parameters is given by Shapiro (2003, in Geophysics Vol.68(Nr.2)). Parameter D is related to the stress sensitivity of the rock. A similar relation was derived by Shapiro and Kaselow (2005, in Geophysics in press) for weak anisotropic rocks under arbitrary load. They describe the stress dependent anisotropy in terms of Thomson's (1986, in Geophysics, Vol. 51(Nr.10)) anisotropy parameters ɛ and γ as a function of stress in the case of an initially isotropic rock: ɛ ∝ E2-E3, γ ∝ E3-E2 (2) with Ei=exp (D*Pi). The exponential terms Ei are controlled by the effective stress components Pi. To test this relation, we have conducted a series of triaxial compression tests on dry samples of initially isotropic Etnean Basalt in a servo-controlled MTS loading frame equipped with a pressure cell. Confining pressure was 60, 40 and 20 MPa. Samples were 5 cm in diameter and 10 cm in length. Elastic anisotropy was induced by axial compression of the samples through opening and growth of microcracks predominantly oriented parallel to the sample axis. Ultrasonic P- and S- wave velocities were monitored parallel and normal to the sample axis by an array of 20 piezoceramic transducers glued to the surface. Preamplified full waveform signals were stored in two 12 channel transient recorders. According to equation 2 the anisotropy parameters are

  5. bessel functions for axisymmetric elasticity problems of the elastic

    African Journals Online (AJOL)

    HOD

    2, 3DEPARTMENT OF CIVIL ENGINEERING, UNIVERSITY OF NIGERIA, NSUKKA. ENUGU STATE. ... theory of elasticity and in the case of vertical applied loads, was first ... partial differential equations in bodies having cylindrical symmetry.

  6. Strain fluctuations and elastic constants

    Energy Technology Data Exchange (ETDEWEB)

    Parrinello, M.; Rahman, A.

    1982-03-01

    It is shown that the elastic strain fluctuations are a direct measure of elastic compliances in a general anisotropic medium; depending on the ensemble in which the fluctuation is measured either the isothermal or the adiabatic compliances are obtained. These fluctuations can now be calculated in a constant enthalpy and pressure, and hence, constant entropy, ensemble due to recent develpments in the molecular dynamics techniques. A calculation for a Ni single crystal under uniform uniaxial 100 tensile or compressive load is presented as an illustration of the relationships derived between various strain fluctuations and the elastic modulii. The Born stability criteria and the behavior of strain fluctuations are shown to be related.

  7. High energy elastic hadron scattering

    International Nuclear Information System (INIS)

    Fearnly, T.A.

    1986-04-01

    The paper deals with the WA7 experiment at the CERN super proton synchrotron (SPS). The elastic differential cross sections of pion-proton, kaon-proton, antiproton-proton, and proton-proton at lower SPS energies over a wide range of momentum transfer were measured. Some theoretical models in the light of the experimental results are reviewed, and a comprehensive impact parameter analysis of antiproton-proton elastic scattering over a wide energy range is presented. A nucleon valence core model for high energy proton-proton and antiproton-proton elastic scattering is described

  8. CONCERNING THE ELASTIC ORTHOTROPIC MODEL APPLIED TO WOOD ELASTIC PROPERTIES

    OpenAIRE

    Tadeu Mascia,Nilson

    2003-01-01

    Among the construction materials, wood reveals an orthotropic pattern, because of unique characteristics in its internal structure with three axes of wood biological directions (longitudinal, tangential and radial). elastic symmetry: longitudinal, tangential and radial, reveals an orthotropic pattern. The effect of grain angle orientation onin the elastic modulus constitutes the fundamental cause forof wood anisotropy. It is responsible for the greatest changes in the values of the constituti...

  9. Spectral dimension of elastic Sierpinski gaskets with general elastic forces

    International Nuclear Information System (INIS)

    Liu, S.H.; Liu, A.J.

    1985-01-01

    The spectral dimension is calculated for a Sierpinski gasket with the most general elastic restoring forces allowed by symmetry. The elastic forces consist of bond-stretching and angle-bending components. The spectral dimension is the same as that for the bond-stretching-force (central-force) model. This demonstrates that on the Sierpinski gasket the two types of forces belong to the same universality class

  10. Stable Boundary Layer Issues

    OpenAIRE

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The development of robust stable boundary layer parameterizations for use in NWP and climate models is hampered by the multiplicity of processes and their unknown interactions. As a result, these models suffer ...

  11. Stable isogeometric analysis of trimmed geometries

    Science.gov (United States)

    Marussig, Benjamin; Zechner, Jürgen; Beer, Gernot; Fries, Thomas-Peter

    2017-04-01

    We explore extended B-splines as a stable basis for isogeometric analysis with trimmed parameter spaces. The stabilization is accomplished by an appropriate substitution of B-splines that may lead to ill-conditioned system matrices. The construction for non-uniform knot vectors is presented. The properties of extended B-splines are examined in the context of interpolation, potential, and linear elasticity problems and excellent results are attained. The analysis is performed by an isogeometric boundary element formulation using collocation. It is argued that extended B-splines provide a flexible and simple stabilization scheme which ideally suits the isogeometric paradigm.

  12. Rayleigh-Taylor instability in accelerated elastic-solid slabs

    Science.gov (United States)

    Piriz, S. A.; Piriz, A. R.; Tahir, N. A.

    2017-12-01

    We develop the linear theory for the asymptotic growth of the incompressible Rayleigh-Taylor instability of an accelerated solid slab of density ρ2, shear modulus G , and thickness h , placed over a semi-infinite ideal fluid of density ρ110.1007/s000330050121] to arbitrary values of AT and unveil the singular feature of an instability threshold below which the slab is stable for any perturbation wavelength. As a consequence, an accelerated elastic-solid slab is stable if ρ2g h /G ≤2 (1 -AT) /AT .

  13. Health care demand elasticities by type of service.

    Science.gov (United States)

    Ellis, Randall P; Martins, Bruno; Zhu, Wenjia

    2017-09-01

    We estimate within-year price elasticities of demand for detailed health care services using an instrumental variable strategy, in which individual monthly cost shares are instrumented by employer-year-plan-month average cost shares. A specification using backward myopic prices gives more plausible and stable results than using forward myopic prices. Using 171 million person-months spanning 73 employers from 2008 to 2014, we estimate that the overall demand elasticity by backward myopic consumers is -0.44, with higher elasticities of demand for pharmaceuticals (-0.44), specialists visits (-0.32), MRIs (-0.29) and mental health/substance abuse (-0.26), and lower elasticities for prevention visits (-0.02) and emergency rooms (-0.04). Demand response is lower for children, in larger firms, among hourly waged employees, and for sicker people. Overall the method appears promising for estimating elasticities for highly disaggregated services although the approach does not work well on services that are very expensive or persistent. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Closed retrograde retrieval of the distal broken segment of femoral cannulated intramedullary nail using a ball-tipped guide wire.

    Science.gov (United States)

    Metikala, Sreenivasulu; Mohammed, Riazuddin

    2011-07-01

    Extracting broken segments of intramedullay nails from long bones can be an operative challenge, particularly from the distal end. We report a case series where a simple and reproducible technique of extracting broken femoral cannulated nails using a ball-tipped guide wire is described. This closed technique involves no additional equipment or instruments. Eight patients who underwent the described method were included in the study. The technique involves using a standard plain guide wire passed through the cannulated distal broken nail segment after extraction of the proximal nail fragment. The plain guide wire is then advanced distally into the knee joint carefully under fluoroscopy imaging. Over this wire, a 5-millimeter (mm) cannulated large drill bit is used to create a track up to the distal broken nail segment. Through the small knee wound, a ball-tipped guide wire is passed, smooth end first, till the ball engages the end of the nail. The guide wire is then extracted along with the broken nail through the proximal wound. The method was successfully used in all eight patients for removal of broken cannulated intramedullary nail from the femoral canal without any complications. All patients underwent exchange nailing with successful bone union in six months. None of the patients had any problems at the knee joint at the final follow-up. We report a technique for successful extraction of the distal fragment of broken femoral intramedullary nails without additional surgical approaches.

  15. Robotic technique improves entry point alignment for intramedullary nailing of femur fractures compared to the conventional technique: a cadaveric study.

    Science.gov (United States)

    Suero, Eduardo M; Westphal, Ralf; Citak, Musa; Hawi, Nael; Liodakis, Emmanouil; Krettek, Christian; Stuebig, Timo

    2017-08-11

    We aimed to test whether a robotic technique would offer more accurate access to the proximal femoral medullary cavity for insertion of an intramedullary nail compared to the conventional manual technique. The medullary cavity of ten femur specimens was accessed in a conventional fashion using fluoroscopic control. In ten additional femur specimens, ISO-C 3D scans were obtained and a computer program calculated the ideal location of the cavity opening based on the trajectory of the medullary canal. In both techniques, the surgeon opened the cavity using a drill and inserted a radiopaque tube that matched the diameter of the cavity. The mean difference in angle between the proximal opening and the medullary canal in the shaft of the femur was calculated for both groups. Robotic cavity opening was more accurate than the manual technique, with a mean difference in trajectory between the proximal opening and the shaft canal of 2.0° (95% CI 0.6°-3.5°) compared to a mean difference of 4.3° (95% CI 2.11°-6.48°) using the manual technique (P = 0.0218). The robotic technique was more accurate than the manual procedure for identifying the optimal location for opening the medullary canal for insertion of an intramedullary nail. Additional advantages may include a reduction in total radiation exposure, as only one ISO-C 3D scan is needed, as opposed to multiple radiographs when using the manual technique.

  16. The effect of intramedullary bone endoscopy on the endosteal blood supply in long bones. An experimental study in sheep.

    Science.gov (United States)

    Herget, Georg W; Haberstroh, Jörg; Südkamp, Norbert; Riede, Ursus; Oberst, Michael

    2011-02-01

    This study investigated whether the Intramedullary Bone Endoscopy (IBE) procedure within the cavity of an intact long bone will interfere with the local endosteal blood supply. In a sheep model, 10 animals underwent the IBE procedure with complete perioperative anaesthesiology monitoring. After the femora were harvested, histological analysis was performed to examine destruction of the endosteum and consecutive reduction in perfusion. Only one animal showed evidence of detachment of the endosteum with destruction of several microns of the endosteum, although this did not interfere with the cortical perfusion. None of the vessels were occluded by fat or other causes of occlusion, e.g. blood coagulation. Our findings indicate that with the IBE procedure under visual control there is a potential risk to damage the endosteum. However, the interference was limited to a small part of the endosteum and did not lead to a reduction in the cortical perfusion. Clinical use could be in localized intramedullary lesions such as osteomyelitis or benign bone tumours.

  17. A comparative study of intramedullary interlocking nailing and minimally invasive plate osteosynthesis in extra articular distal tibial fractures.

    Science.gov (United States)

    Daolagupu, Arup K; Mudgal, Ashwani; Agarwala, Vikash; Dutta, Kaushik K

    2017-01-01

    Extraarticular distal tibial fractures are among the most challenging fractures encountered by an orthopedician for treatment because of its subcutaneous location, poor blood supply and decreased muscular cover anteriorly, complications such as delayed union, nonunion, wound infection, and wound dehiscence are often seen as a great challenge to the surgeon. Minimally invasive plate osteosynthesis (MIPO) and intramedullary interlocking nail (IMLN) are two well-accepted and effective methods, but each has been historically related to complications. This study compares clinical and radiological outcome in extraarticular distal tibia fractures treated by intramedullary interlocking nail (IMLN) and minimally invasive plate osteosynthesis (MIPO). 42 patients included in this study, 21 underwent IMLN and 21 were treated with MIPO who met the inclusion criteria and operated between June 2014 and May 2015. Patients were followed up for clinical and radiological evaluation. In IMLN group, average union time was 18.26 weeks compared to 21.70 weeks in plating group which was significant ( P ankle stiffness, and infection, were seen in interlocking group as compared to plating group. Average functional outcome according to American Orthopedic Foot and Ankle Society score was measured which came out to be 96.67. IMLN group was associated with lesser duration of surgery, earlier weight bearing and union rate, lesser incidence of infection and implant irritation which makes it a preferable choice for fixation of extra-articular distal tibial fractures. However, larger randomized controlled trials are required for confirming the results.

  18. Flexible intramedullary nailing for unicameral cysts in children's long bones : Level of evidence: lV, case series.

    Science.gov (United States)

    Glanzmann, Michael C; Campos, Lautaro

    2007-07-01

    The purpose of this study was to evaluate the outcome of flexible intramedullary nailing for unicameral bone cysts in terms of function and osseous consolidation. Twenty-two unicameral bone cysts in children's long bones were treated by flexible intramedullary nailing. In 13 cases the bone cyst was diagnosed in a traumatic event leading to a pathologic fracture. Fifteen patients were referred to our clinic after failed conservative treatment. In 16 patients the cyst was located in the humerus, and in 6 patients in the femur. Mean duration of follow-up after surgery was 24 months. According to Capanna's criteria healing was obtained in 20 cases with a mean time of 16 months. Sixteen cysts healed completely. Four lesions were classified as grade 2, meaning that residual radiolucencies were radiographically visible at the latest follow-up. Two recurrences of humeral cysts were seen at 16 and 18 months postoperatively. The complication rate was minimal. Due to the immediate stabilization of the lesion aftercare becomes facile. This method allows prompt mobilization and early weight bearing without the necessity of a plaster cast. Further it prevents effectively the most common complication, a re-fracture or a pathologic fracture. Therefore we propose this surgical procedure as the treatment of choice for unicameral bone cysts in children's long bones.

  19. Microfluidic enhancement of intramedullary pressure increases interstitial fluid flow and inhibits bone loss in hindlimb suspended mice.

    Science.gov (United States)

    Kwon, Ronald Y; Meays, Diana R; Tang, W Joyce; Frangos, John A

    2010-08-01

    Interstitial fluid flow (IFF) has been widely hypothesized to mediate skeletal adaptation to mechanical loading. Although a large body of in vitro evidence has demonstrated that fluid flow stimulates osteogenic and antiresorptive responses in bone cells, there is much less in vivo evidence that IFF mediates loading-induced skeletal adaptation. This is due in large part to the challenges associated with decoupling IFF from matrix strain. In this study we describe a novel microfluidic system for generating dynamic intramedullary pressure (ImP) and IFF within the femurs of alert mice. By quantifying fluorescence recovery after photobleaching (FRAP) within individual lacunae, we show that microfluidic generation of dynamic ImP significantly increases IFF within the lacunocanalicular system. In addition, we demonstrate that dynamic pressure loading of the intramedullary compartment for 3 minutes per day significantly eliminates losses in trabecular and cortical bone mineral density in hindlimb suspended mice, enhances trabecular and cortical structural integrity, and increases endosteal bone formation rate. Unlike previously developed modalities for enhancing IFF in vivo, this is the first model that allows direct and dynamic modulation of ImP and skeletal IFF within mice. Given the large number of genetic tools for manipulating the mouse genome, this model is expected to serve as a powerful investigative tool in elucidating the role of IFF in skeletal adaptation to mechanical loading and molecular mechanisms mediating this process.

  20. Intramedullary stabilization and over-nail lengthening as two-stage treatment of femoral nonunion with shortening. Case study.

    Science.gov (United States)

    Kącki, Wojciech; Jasiewicz, Barbara; Radło, Paweł

    2014-01-01

    Nonunion is one of the most serious complications of long bone fractures. It may be accompanied by a shortening of the segment. The authors describe the case of a 21-year-old woman with a post-traumatic nonunion with shortening of the femur. Treatment was divided into two stages: first, a previously placed nail was removed and new intramedullary stabilization was carried out while bone defects were filled with a bone graft substitute and platelet rich plasma was administered. After the nonunion had healed, the femur was lengthened over an external fixator and an intramedullary nail, resulting in equality of limb length. After eight years of follow-up, the lower limbs remain equal with a properly aligned long axis of the lower limb operated on and a full range of motion in the joints. The treatment strategy described in our article may be an alternative to one-stage surgery if the patient does not consent to it or in the presence of contraindications, but it is associated with a longer treatment time and necessity of additional surgeries.

  1. A pilot study on the use of cerebrospinal fluid cell-free DNA in intramedullary spinal ependymoma.

    Science.gov (United States)

    Connolly, Ian David; Li, Yingmei; Pan, Wenying; Johnson, Eli; You, Linya; Vogel, Hannes; Ratliff, John; Hayden Gephart, Melanie

    2017-10-01

    Cerebrospinal fluid (CSF) represents a promising source of cell-free DNA (cfDNA) for tumors of the central nervous system. A CSF-based liquid biopsy may obviate the need for riskier tissue biopsies and serve as a means for monitoring tumor recurrence or response to therapy. Spinal ependymomas most commonly occur in adults, and aggressive resection must be delicately balanced with the risk of injury to adjacent normal tissue. In patients with subtotal resection, recurrence commonly occurs. A CSF-based liquid biopsy matched to the patient's spinal ependymoma mutation profile has potential to be more sensitive then surveillance MRI, but the utility has not been well characterized for tumors of the spinal cord. In this study, we collected matched blood, tumor, and CSF samples from three adult patients with WHO grade II intramedullary spinal ependymoma. We performed whole exome sequencing on matched tumor and normal DNA to design Droplet Digital™ PCR (ddPCR) probes for tumor and wild-type mutations. We then interrogated CSF samples for tumor-derived cfDNA by performing ddPCR on extracted cfDNA. Tumor cfDNA was not reliably detected in the CSF of our cohort. Anatomic sequestration and low grade of intramedullary spinal cord tumors likely limits the role of CSF liquid biopsy.

  2. Astronomical optics and elasticity theory

    CERN Document Server

    Lemaitre, Gerard Rene

    2008-01-01

    Astronomical Optics and Elasticity Theory provides a very thorough and comprehensive account of what is known in this field. After an extensive introduction to optics and elasticity, the book discusses variable curvature and multimode deformable mirrors, as well as, in depth, active optics, its theory and applications. Further, optical design utilizing the Schmidt concept and various types of Schmidt correctors, as well as the elasticity theory of thin plates and shells are elaborated upon. Several active optics methods are developed for obtaining aberration corrected diffraction gratings. Further, a weakly conical shell theory of elasticity is elaborated for the aspherization of grazing incidence telescope mirrors. The very didactic and fairly easy-to-read presentation of the topic will enable PhD students and young researchers to actively participate in challenging astronomical optics and instrumentation projects.

  3. Uniqueness theorems in linear elasticity

    CERN Document Server

    Knops, Robin John

    1971-01-01

    The classical result for uniqueness in elasticity theory is due to Kirchhoff. It states that the standard mixed boundary value problem for a homogeneous isotropic linear elastic material in equilibrium and occupying a bounded three-dimensional region of space possesses at most one solution in the classical sense, provided the Lame and shear moduli, A and J1 respectively, obey the inequalities (3 A + 2 J1) > 0 and J1>O. In linear elastodynamics the analogous result, due to Neumann, is that the initial-mixed boundary value problem possesses at most one solution provided the elastic moduli satisfy the same set of inequalities as in Kirchhoffs theorem. Most standard textbooks on the linear theory of elasticity mention only these two classical criteria for uniqueness and neglect altogether the abundant literature which has appeared since the original publications of Kirchhoff. To remedy this deficiency it seems appropriate to attempt a coherent description ofthe various contributions made to the study of uniquenes...

  4. Wrinkling of Pressurized Elastic Shells

    KAUST Repository

    Vella, Dominic; Ajdari, Amin; Vaziri, Ashkan; Boudaoud, Arezki

    2011-01-01

    We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells

  5. Management of Femoral Shaft Fractures with Elastic Titanium Nails in Pediatric Patients

    Directory of Open Access Journals (Sweden)

    Yunus Güzel

    2016-06-01

    Full Text Available Objective: The aim of this study was to evaluate the func­tional and radiological results of the application of intra­medullary fixation with elastic titanium nails in unstable femoral fractures and to determine the factors affecting these results. Methods: A total of 32 patients aged 4-17 years treated with intramedullary elastic nails for a femoral diaphysis fracture between 2001 and 2014 were included. The frac­ture was left side in 12 cases, right side in 18 and bilateral in 2. The fracture pattern was determined as fragmented in 11 cases, short oblique in 11, transverse in 8 and spi­ral in 4. The same surgical technique and postoperative care was applied to all the patients. Sagittal and coronal angle measurements were made from postoperative and follow-up anterior-posterior and lateral radiographs. The mean follow-up period was 54 months (12-156 months. Positive union criteria were accepted as pain-free weight-bearing and callus bridging in at least 3 cortices seen on direct radiographs. Results: Union was achieved in all except one patient. They were able to return to previous activities with full knee and hip joint range of movement. Radiologically, the mean time to union was determined as 9 weeks (range, 6-16 weeks. Limb shortness was determined in 5 (14% patients. No significant association was detected be­tween shortness and fracture pattern. No varus or valgus angulation of >10˚ was determined in any patient. Conclusion: Application of titanium elastic nails in pe­diatric femoral diaphysis fractures is a comfortable, eco­nomic, and reliable method which is allows early weight-bearing.

  6. CONFERENCE: Elastic and diffractive scattering

    Energy Technology Data Exchange (ETDEWEB)

    White, Alan

    1989-09-15

    Elastic scattering, when particles appear to 'bounce' off each other, and the related phenomena of diffractive scattering are currently less fashionable than the study of hard scattering processes. However this could change rapidly if unexpected results from the UA4 experiment at the CERN Collider are confirmed and their implications tested. These questions were highlighted at the third 'Blois Workshop' on Elastic and Diffractive Scattering, held early in May on the Evanston campus of Northwestern University, near Chicago.

  7. A Labor Supply Elasticity Accord?

    OpenAIRE

    Lars Ljungqvist; Thomas J. Sargent

    2011-01-01

    A dispute about the size of the aggregate labor supply elasticity has been fortified by a contentious aggregation theory used by real business cycle theorists. The replacement of that aggregation theory with one more congenial to microeconomic observations opens possibilities for an accord about the aggregate labor supply elasticity. The new aggregation theory drops features to which empirical microeconomists objected and replaces them with life-cycle choices. Whether the new aggregation theo...

  8. Integrodifferential relations in linear elasticity

    CERN Document Server

    Kostin, Georgy V

    2012-01-01

    This work treats the elasticity of deformed bodies, including the resulting interior stresses and displacements.It also takes into account that some of constitutive relations can be considered in a weak form. To discuss this problem properly, the method of integrodifferential relations is used, and an advanced numerical technique for stress-strain analysis is presented and evaluated using various discretization techniques. The methods presented in this book are of importance for almost all elasticity problems in materials science and mechanical engineering.

  9. In Situ elastic property sensors

    International Nuclear Information System (INIS)

    Olness, D.; Hirschfeld, T.; Kishiyama, K.; Steinhaus, R.

    1987-01-01

    Elasticity is an important property of many materials. Loss of elasticity can have serious consequences, such as when a gasket deteriorates and permits leakage of an expensive or hazardous material, or when a damping system begins to go awry. Loss of elasticity can also provide information related to an ancillary activity such as degradation of electrical insulation, loss of plasticizer in a plastic, or changes in permeability of a thin film. In fact, the mechanical properties of most organic compounds are altered when the compound degrades. Thus, a sensor for the mechanical properties can be used to monitor associated characteristics as well. A piezoelectric material in contact with an elastomer forms an oscillating system that can provide real-time elasticity monitoring. This combination constitutes a forced harmonic oscillator with damping provided by the elastomer. A ceramic oscillator with a total volume of a few mm 3 was used as an elasticity sensor. It was placed in intimate contact with an elastomer and then monitored remotely with a simple oscillator circuit and standard frequency counting electronics. Resonant frequency shifts and changes in Q value were observed corresponding to changes in ambient temperature and/or changes in pressure applied to the sample. Elastomer samples pretreated with ozone (to simulate aging) showed changes in Q value and frequency response, even though there were no visible changes in the elastic samples

  10. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    1982-09-01

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  11. Evolutionary Stable Strategy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 9. Evolutionary Stable Strategy: Application of Nash Equilibrium in Biology. General Article Volume 21 Issue 9 September 2016 pp 803- ... Keywords. Evolutionary game theory, evolutionary stable state, conflict, cooperation, biological games.

  12. Stable Boundary Layer Issues

    NARCIS (Netherlands)

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The

  13. Effect of price elasticity of demand in monopolies with gradient adjustment

    International Nuclear Information System (INIS)

    Cavalli, Fausto; Naimzada, Ahmad

    2015-01-01

    Highlights: •A monopoly with isoelastic demand function is studied. •Reduced rationality monopolist uses gradient adjustment. •If marginal cost is small, increasing elasticity leads to stable dynamics. •For large marginal cost, dynamic can be unstable for both small and large elasticity. -- Abstract: We study a monopolistic market characterized by a constant elasticity demand function, in which the firm technology is described by a linear total cost function. The firm is assumed to be boundedly rational and to follow a gradient rule to adjust the production level in order to optimize its profit. We focus on what happens on varying the price elasticity of demand, studying the effect on the equilibrium stability. We prove that, depending on the relation between the market size and the marginal cost, two different scenarios are possible, in which elasticity has either a stabilizing or a mixed stabilizing/destabilizing effect

  14. End-threaded intramedullary positive profile screw ended self-tapping pin (Admit pin) - A cost-effective novel implant for fixing canine long bone fractures.

    Science.gov (United States)

    Chanana, Mitin; Kumar, Adarsh; Tyagi, Som Prakash; Singla, Amit Kumar; Sharma, Arvind; Farooq, Uiase Bin

    2018-02-01

    The current study was undertaken to evaluate the clinical efficacy of end-threaded intramedullary pinning for management of various long bone fractures in canines. This study was conducted in two phases, managing 25 client-owned dogs presented with different fractures. The technique of application of end-threaded intramedullary pinning in long bone fractures was initially standardized in 6 clinical patients presented with long bone fractures. In this phase, end-threaded pins of different profiles, i.e., positive and negative, were used as the internal fixation technique. On the basis of results obtained from standardization phase, 19 client-owned dogs clinically presented with different fractures were implanted with end-threaded intramedullary positive profile screw ended self-tapping pin in the clinical application phase. The patients, allocated randomly in two groups, when evaluated postoperatively revealed slight pin migration in Group-I (negative profile), which resulted in disruption of callus site causing delayed union in one case and large callus formation in other two cases whereas no pin migration was observed in Group-II (positive profile). Other observations in Group-I was reduced muscle girth and delayed healing time as compared to Group-II. In clinical application, phase 21 st and 42 nd day post-operative radiographic follow-up revealed no pin migration in any of the cases, and there was no bone shortening or fragment collapse in end-threaded intramedullary positive profile screw ended self-tapping pin. The end-threaded intramedullary positive profile screw ended self-tapping pin used for fixation of long bone fractures in canines can resist pin migration, pin breakage, and all loads acting on the bone, i.e., compression, tension, bending, rotation, and shearing to an extent with no post-operative complications.

  15. Temperature dependence of elastic properties of paratellurite

    International Nuclear Information System (INIS)

    Silvestrova, I.M.; Pisarevskii, Y.V.; Senyushenkov, P.A.; Krupny, A.I.

    1987-01-01

    New data are presented on the temperature dependence of the elastic wave velocities, elastic stiffness constants, and thermal expansion of paratellurite. It is shown that the external pressure appreciably influences the elastic properties of TeO 2 , especially the temperature dependence of the elastic modulus connected with the crystal soft mode. (author)

  16. Plate Versus Intramedullary Nail Fixation of Anterior Tibial Stress Fractures: A Biomechanical Study.

    Science.gov (United States)

    Markolf, Keith L; Cheung, Edward; Joshi, Nirav B; Boguszewski, Daniel V; Petrigliano, Frank A; McAllister, David R

    2016-06-01

    Anterior midtibial stress fractures are an important clinical problem for patients engaged in high-intensity military activities or athletic training activities. When nonoperative treatment has failed, intramedullary (IM) nail and plate fixation are 2 surgical options used to arrest the progression of a fatigue fracture and allow bone healing. A plate will be more effective than an IM nail in preventing the opening of a simulated anterior midtibial stress fracture from tibial bending. Controlled laboratory study. Fresh-frozen human tibias were loaded by applying a pure bending moment in the sagittal plane. Thin transverse saw cuts, 50% and 75% of the depth of the anterior tibial cortex, were created at the midtibia to simulate a fatigue fracture. An extensometer spanning the defect was used to measure the fracture opening displacement (FOD) before and after the application of IM nail and plate fixation constructs. IM nails were tested without locking screws, with a proximal screw only, and with proximal and distal screws. Plates were tested with unlocked bicortical screws (standard compression plate) and locked bicortical screws; both plate constructs were tested with the plate edge placed 1 mm from the anterior tibial crest (anterior location) and 5 mm posterior to the crest. For the 75% saw cut depth, the mean FOD values for all IM nail constructs were 13% to 17% less than those for the saw cut alone; the use of locking screws had no significant effect on the FOD. The mean FOD values for all plate constructs were significantly less than those for all IM nail constructs. The mean FOD values for all plates were 28% to 46% less than those for the saw cut alone. Anterior plate placement significantly decreased mean FOD values for both compression and locked plate constructs, but the mean percentage reductions for locked and unlocked plates were not significantly different from each other for either plate placement. The percentage FOD reductions for all plate

  17. Change of elastic constants induced by point defects in hop crystals

    International Nuclear Information System (INIS)

    Tome, C.

    1979-10-01

    An approximate model is developed to calculate the change of elastic constants induced by point defects in hcp metals, supposed the defect configuration is known. General expressions relating the change of elastic moduli to the final atomic coordinates and to the defect force field are derived using the specific symmetry of the defect. Explicit calculations are done for Mg. The predicted change of elastic moduli turns out to be negative for vacancies and trigonal interstitials while for hexagonal interstitials a positive change is predicted. Compatibility with experimental data would suggest that the trigonal configuration is the stable one. (author)

  18. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  19. Applications of stable isotopes

    International Nuclear Information System (INIS)

    Letolle, R.; Mariotti, A.; Bariac, T.

    1991-06-01

    This report reviews the historical background and the properties of stable isotopes, the methods used for their measurement (mass spectrometry and others), the present technics for isotope enrichment and separation, and at last the various present and foreseeable application (in nuclear energy, physical and chemical research, materials industry and research; tracing in industrial, medical and agronomical tests; the use of natural isotope variations for environmental studies, agronomy, natural resources appraising: water, minerals, energy). Some new possibilities in the use of stable isotope are offered. A last chapter gives the present state and forecast development of stable isotope uses in France and Europe

  20. The Morishima Gross elasticity of substitution

    OpenAIRE

    Blackorby, Charles; Primont, Daniel; Russell, R. Robert

    2007-01-01

    We show that the Hotelling-Lau elasticity of substitution, an extension of the Allen-Uzawa elasticity to allow for optimal output-quantity (or utility) responses to changes in factor prices, inherits all of the failings of the Allen-Uzawa elasticity identified by Blackorby and Russell [1989 AER]. An analogous extension of the Morishima elasticity of substitution to allow for output quantity changes preserves the salient properties of the original Hicksian notion of elasticity of substitution.

  1. The percutaneous use of a pointed reduction clamp during intramedullary nailing of distal third tibial shaft fractures.

    Science.gov (United States)

    Forman, Jordanna M; Urruela, Adriana M; Egol, Kenneth A

    2011-12-01

    The purpose of this retrospective chart and radiographic review is to describe an effective reduction technique during intramedullary nailing of distal metaphyseal tibia fractures with the use of a pointed percutaneous clamp. Between 2007 and 2010, 100 patients who sustained 102 tibia fractures were definitively treated with an intramedullary nail at one of two medical centers. Diaphyseal fractures and injuries with an associated disruption of the distal tibiofibular joint were excluded from our study. A total of 27 patients with 27 distal metaphyseal tibia fractures (OTA types 42-A, 43-A, and 43-B) were included. All 27 patients underwent IM nailing of their fractures with anatomic reduction achieved using a percutaneously placed pointed reduction clamp prior to insertion of the IM implant. Fracture alignment and angular deformity was assessed using goniometric measurement functions on the PACS system (GE, Waukeshau, WI) obtained from preoperative and postoperative anteroposterior and lateral images for all subjects. Malalignment was defined as more than 5 degrees of angulation in any plane. Fourteen of the fractures were classified as OTA 42-A, 9 were OTA 43-A, and 4 were OTA 43-B. Analysis of post-closed reduction, preoperative anteroposterior radiographs revealed a mean of 7.9 degrees of coronal plane (range: 0.9 degrees-26 degrees) angulation. Post closed reduction preoperative lateral radiographs revealed a mean of 6.8 degrees sagittal plane (range: 0 degrees-24.6 degrees) angulation. Postoperative anteroposterior and lateral radiographs showed the distal segment returned to its anatomical alignment with a mean angulation of 0.5 degrees (range, 0 degrees-3.5 degrees) and 0.7 degrees (range, 0 degrees-4.2 degrees) of varus/ valgus and apex anterior/posterior angulation, respectively. These results showed an acceptable postopertative alignment in all 27 distal third fractures. No intra-operative or postoperative complications were noted in the study group. This

  2. [Midterm follow-up results on Asian femoral intramedullary nail for the treatment of segmental and comminuted femoral fractures].

    Science.gov (United States)

    Li, Lang; Gao, Feng; Huang, Qi; Li, Qiang; Xie, Lin; Zhang, Bin

    2016-06-01

    To investigate midterm follow-up results on Asian femoral intramedullary nail in treating segmental and comminuted femoral fractures. Between June 2011 and October 2012,16 patients with segmental and comminuted femoral fractures were treated with minimally invasive reset and Asian femoral intramedullary nail under extension table. Among them, there were 10 males and 6 females aged from 21 to 49 years old with an average of 34.5 years old; the time from injury to operation ranged from 3 to 24 d with an average of 9.1 d. There were 6 cases were type C1,2 cases were type C2 and 8 cases were type C3 according to AO classification. X-ray of femoral segment at 3,6 and 12 months after operation were applied for evaluating fracture healing. Harris score of hip joint and HSS score of knee joint were used to evaluate postoperative function. All patients were followed up from 24 to 36 months with an average of 28.4 months. Operative time was from 88 to 112 min with an average of 90.7 min; blood loss ranged from 150 to 200 ml with an average of 188.75 ml; the time of fracture healing was from 5 to 9 months with an average of 5.4 months. All incision were healed at stage I. No loosening, breakage of internal fixation and displacement of fracture were occurred. There were no significant differences in Harris score of hip joint at 3, 6 and 12 months after operation (F = 0.07, P = 0.893 > 0.05), 10 cases obtained excellent results, 5 good and 1 moderate. There was no obvious meaning in HSS score of knee joint (F = 0.08,P = 0.876 > 0.05), 9 cases obtained excellent results, 6 good and 1 poor. Asian femoral intramedullary nail could treat segmental and comminuted femoral fractures by using variety of less invasive ways,which has advantages of less trauma, quick recovery of function and satisfied midterm following-up results. But long term following-up effects remains to be seen.

  3. Skeletal adaptation to intramedullary pressure-induced interstitial fluid flow is enhanced in mice subjected to targeted osteocyte ablation.

    Science.gov (United States)

    Kwon, Ronald Y; Meays, Diana R; Meilan, Alexander S; Jones, Jeremiah; Miramontes, Rosa; Kardos, Natalie; Yeh, Jiunn-Chern; Frangos, John A

    2012-01-01

    Interstitial fluid flow (IFF) is a potent regulatory signal in bone. During mechanical loading, IFF is generated through two distinct mechanisms that result in spatially distinct flow profiles: poroelastic interactions within the lacunar-canalicular system, and intramedullary pressurization. While the former generates IFF primarily within the lacunar-canalicular network, the latter generates significant flow at the endosteal surface as well as within the tissue. This gives rise to the intriguing possibility that loading-induced IFF may differentially activate osteocytes or surface-residing cells depending on the generating mechanism, and that sensation of IFF generated via intramedullary pressurization may be mediated by a non-osteocytic bone cell population. To begin to explore this possibility, we used the Dmp1-HBEGF inducible osteocyte ablation mouse model and a microfluidic system for modulating intramedullary pressure (ImP) to assess whether structural adaptation to ImP-driven IFF is altered by partial osteocyte depletion. Canalicular convective velocities during pressurization were estimated through the use of fluorescence recovery after photobleaching and computational modeling. Following osteocyte ablation, transgenic mice exhibited severe losses in bone structure and altered responses to hindlimb suspension in a compartment-specific manner. In pressure-loaded limbs, transgenic mice displayed similar or significantly enhanced structural adaptation to Imp-driven IFF, particularly in the trabecular compartment, despite up to ∼50% of trabecular lacunae being uninhabited following ablation. Interestingly, regression analysis revealed relative gains in bone structure in pressure-loaded limbs were correlated with reductions in bone structure in unpressurized control limbs, suggesting that adaptation to ImP-driven IFF was potentiated by increases in osteoclastic activity and/or reductions in osteoblastic activity incurred independently of pressure loading

  4. Skeletal adaptation to intramedullary pressure-induced interstitial fluid flow is enhanced in mice subjected to targeted osteocyte ablation.

    Directory of Open Access Journals (Sweden)

    Ronald Y Kwon

    Full Text Available Interstitial fluid flow (IFF is a potent regulatory signal in bone. During mechanical loading, IFF is generated through two distinct mechanisms that result in spatially distinct flow profiles: poroelastic interactions within the lacunar-canalicular system, and intramedullary pressurization. While the former generates IFF primarily within the lacunar-canalicular network, the latter generates significant flow at the endosteal surface as well as within the tissue. This gives rise to the intriguing possibility that loading-induced IFF may differentially activate osteocytes or surface-residing cells depending on the generating mechanism, and that sensation of IFF generated via intramedullary pressurization may be mediated by a non-osteocytic bone cell population. To begin to explore this possibility, we used the Dmp1-HBEGF inducible osteocyte ablation mouse model and a microfluidic system for modulating intramedullary pressure (ImP to assess whether structural adaptation to ImP-driven IFF is altered by partial osteocyte depletion. Canalicular convective velocities during pressurization were estimated through the use of fluorescence recovery after photobleaching and computational modeling. Following osteocyte ablation, transgenic mice exhibited severe losses in bone structure and altered responses to hindlimb suspension in a compartment-specific manner. In pressure-loaded limbs, transgenic mice displayed similar or significantly enhanced structural adaptation to Imp-driven IFF, particularly in the trabecular compartment, despite up to ∼50% of trabecular lacunae being uninhabited following ablation. Interestingly, regression analysis revealed relative gains in bone structure in pressure-loaded limbs were correlated with reductions in bone structure in unpressurized control limbs, suggesting that adaptation to ImP-driven IFF was potentiated by increases in osteoclastic activity and/or reductions in osteoblastic activity incurred independently of

  5. Analysing Stable Time Series

    National Research Council Canada - National Science Library

    Adler, Robert

    1997-01-01

    We describe how to take a stable, ARMA, time series through the various stages of model identification, parameter estimation, and diagnostic checking, and accompany the discussion with a goodly number...

  6. Investigations of structural, elastic, electronic and thermodynamic properties of lutetium filled skutterudite LuFe4P12 under pressure effect: FP-LMTO method

    Directory of Open Access Journals (Sweden)

    Boudia Keltouma

    2015-12-01

    Full Text Available Structural, elastic, electronic and thermodynamic properties of ternary cubic filled skutterudite compound were calculated. We have computed the elastic modulus and its pressure dependence. From the elastic parameter behavior, it is inferred that this compound is elastically stable and ductile in nature. Through the quasi-harmonic Debye model, in which phononic effects are considered, the effect of pressure P (0 to 50 GPa and temperature T (0 to 3000 °C on the lattice constant, elastic parameters, bulk modulus B, heat capacity, thermal expansion coefficient α, internal energy U, entropy S, Debye temperature θD, Helmholtz free energy A, and Gibbs free energy G are investigated.

  7. Elastic scattering and total reaction cross section for the 6He + 27Al system

    International Nuclear Information System (INIS)

    Benjamim, E.A.; Lepine-Szily, A.; Mendes Junior, D.R.; Lichtenthaeler, R.; Guimaraes, V.; Gomes, P.R.S.; Chamon, L.C.; Hussein, M.S.; Moro, A.M.; Arazi, A.; Padron, I.; Alcantara Nunez, J.; Assuncao, M.; Barioni, A.; Camargo, O.; Denke, R.Z.; Faria, P.N. de; Pires, K.C.C.

    2007-01-01

    The elastic scattering of the radioactive halo nucleus 6 He on 27 Al target was measured at four energies close to the Coulomb barrier using the RIBRAS (Radioactive Ion Beams in Brazil) facility. The Sao Paulo Potential (SPP) was used and its diffuseness and imaginary strength were adjusted to fit the elastic scattering angular distributions. Reaction cross-sections were extracted from the optical model fits. The reduced reaction cross-sections of 6 He on 27 Al are similar to those for stable, weakly bound projectiles as 6,7 Li, 9 Be and larger than stable, tightly bound projectile as 16 O on 27 Al

  8. Phason elasticity and surface roughening

    International Nuclear Information System (INIS)

    Tang Leihan; Jaric, M.V.

    1990-01-01

    The phason elasticity of two-dimensional (2D) equilibrium quasicrystals is discussed in analogy with surface roughening phenomena. Taking a Penrose tiling model as an example, we show that the phason elastic energy is linear in the phason strain at zero temperature (T = 0), but becomes quadratic at any T > 0 and sufficiently small strain. Heuristic and real-space renormalization group arguments are given for the thermal roughening of the hyper-surface which represents quasicrystal tiling. Monte Carlo method is applied to illustrate the logarithmically diverging phason fluctuations and power-law diffraction intensities at T > 0. For three-dimensional systems, we present arguments which suggest a finite temperature transition between two quasicrystal phases, characterized by linear and quadratic phason elastic energy, respectively. (author). 17 refs, 12 figs

  9. Appraisal of elastic follow up

    International Nuclear Information System (INIS)

    Roche, R.L.

    1981-08-01

    The aim of this paper is to provide indications to choose what fraction of a self limiting stress can be considered as secondary. At first, considerations are given to a simple structure which could be called ''creep relaxation tensile test''. A bar (with constant cross section) is loaded by an elastic spring in order to obtain a given elongation of the assembly. The stress evolution is studied. Then the creep damage is computed, and compared to the damage corresponding to the elastic computed stress. This comparison gives the fraction of the self limiting stress which must be considered as primary. This involve the structural parameter 0 which is the initial value of the ratio of elastic energy to dissipating power. Extension of the rule is made with the help of KACHANOV approximation. As a conclusion a procedure is described which determines what fraction of a self limiting stress must be considered as primary

  10. Investor response to consumer elasticity

    International Nuclear Information System (INIS)

    Grenaa Jensen, Stine; Meibom, Peter; Ravn, H.F.; Straarup, Sarah

    2004-01-01

    In the Nordic electricity system there is considerable uncertainty with respect to the long-term development in production capacity. The process towards liberalisation of the electricity sector started in a situation with a large reserve margin, but this margin is gradually vanishing. Since the potential investors in new production capacity are unaccustomed with investments under the new regime it is unknown if and when investments will take place. The electricity price is the key market signal to potential investors. The price is settled as a balance between supply and demand, and it is generally assumed that the demand side has an important role in this, and increasingly so. However, since consumers have not earlier had the incentive to respond to electricity prices, no reliable estimate of demand elasticity is known. The purpose of the present study is to analyse the role of electricity demand elasticity for investments in new electricity production capacity. Electricity price scenarios generated with a partial equilibrium model (Balmorel) are combined with a model of investment decisions. In this, various scenarios concerning the development in the demand elasticity are used. The simulated investment decisions are taken in a stochastic, dynamic setting, where a key point is the timing of the investment decision in relation to the gathering of new information relative to the stochastic elements. Based on this, the consequences of the development in consumer price elasticity for investments in a base load and a peak load plant are investigated. The main result of the analysis is that peak load investments can be made unprofitable by the development in consumer price elasticity, such that an investor will tend to wait with his peak load investment, until the development in consumer price elasticity has been revealed. (au)

  11. A case of recurrent breast cancer with intramedullary spinal cord metastasis and symptomatic improvement by Radiation Therapy

    International Nuclear Information System (INIS)

    Wakahara, Makoto; Hosoya, Keiko; Hirooka, Yumi

    2017-01-01

    A 65-year-old woman underwent surgery for right breast cancer (TIN1aM0) in December 2005. In March 2011, the breast cancer recurred with multiple lung and lymph node metastases. In February 2013, because of multiple brain metastases whole-brain radiation therapy was performed. In January 2014, she developed paralysis of the left leg. Spinal cord magnetic resonance imaging revealed a mass lesion (Th12 to L1 level) in the spinal cord, and she was diagnosed with intramedullary spinal cord metastasis (ISCM) from the breast cancer. Spinal cord irradiation reduced the metastasis and improved her paralysis. Although pharmacotherapy was continued, her metastases, with the exception of ISCM, progressed and she died of the disease in November 2014. It is necessary to diagnose ISCM at the time of its onset. Additionally immediate therapeutic intervention can significantly reduce the volume of ISCM, resulting in symptomatic relief from neurological deficit; in this case, radiation therapy was effective. (author)

  12. Decreased QOL and muscle strength are persistent 1 year after intramedullary nailing of a tibial shaft fracture

    DEFF Research Database (Denmark)

    Larsen, Peter; Elsoe, Rasmus; Laessoe, Uffe

    2016-01-01

    was measured with the questionnaire Eq5D-5L and compared to norm data from a reference population. Recordings of pain and contralateral muscle strength (isometric maximal voluntary contraction (MVC) for knee flexion and extension were collected at 6 weeks, 3, 6, and 12 months postoperatively. Ipsilateral MVCs......INTRODUCTION:To evaluate the development in patient-reported quality of life (QOL) and muscle strength in the period from surgery to 12 months postoperatively after intramedullary nailing of a tibial shaft fracture. MATERIALS AND METHODS:The design was a prospective, follow-up cohort study. QOL...... compared to the reference population. Six and 12 months after surgery patients demonstrated decreased muscle strength in the injured leg compared to the non-injured leg for knee extension and flexion (P strength during knee...

  13. Dynamic intramedullary crosspinning technique for repair of distal femoral fractures in dogs and cats: 71 cases (1981-1985)

    International Nuclear Information System (INIS)

    Whitney, W.O.; Schrader, S.C.

    1987-01-01

    Dynamic intramedullary crosspinning was used in the surgical treatment of supracondylar and distal physeal fractures of the femur in 129 dogs and cats over a 5-year period; the records of the 44 dogs and 27 cats with follow-up information up to time of bony union were evaluated. The results were good or excellent in 66 of 71 animals (93%). The mean follow-up period was 22 months. Distal pin migration was the major complication (10 animals; 14%). The pin migrated before bony union in 2 animals because of instability and collapse at the fracture site. The pin migrated in 8 animals after bony union and was associated with intermittent lameness. In 5 of these, pin removal was performed and the lameness resolved

  14. Case with high cervical intramedullary hemangioblastoma associated with arteriovenous fistula. CT with simultaneous intravenous and intrathecal injection of contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Takao; Shoji, Shin-ichi; Yanagisawa, Nobuo; Tada, Tsuyoshi; Kobayashi, Naoki

    1988-02-01

    A 34-year-old woman complained of right hemiparesis and pain in the right hand. Routine X-ray of the cervical portion failed to reveal abnormal findings. CT with intravenous contrast medium showed a large high-density mass in the spinal canal at the level of C2. Right vertebral angiography showed a hypervascular mass. With simultaneous intravenous and intrathecal injections of contrast medium, the tumor was shown as a moderately high-density area and the parenchyma of cord as a thin low-density area surrounding the tumor stain on CT. These CT appearances led to the final diagnosis of high cervical intramedullary hemangioblastoma associated with arteriovenous fistulae. Pathological findings are typical of hemangioblastoma. The usefulness of CT in detecting the localization of hypervascular spinal cord lesions is stressed. (Namekawa, K.).

  15. CONFERENCE: Elastic and diffractive scattering

    International Nuclear Information System (INIS)

    White, Alan

    1989-01-01

    Elastic scattering, when particles appear to 'bounce' off each other, and the related phenomena of diffractive scattering are currently less fashionable than the study of hard scattering processes. However this could change rapidly if unexpected results from the UA4 experiment at the CERN Collider are confirmed and their implications tested. These questions were highlighted at the third 'Blois Workshop' on Elastic and Diffractive Scattering, held early in May on the Evanston campus of Northwestern University, near Chicago

  16. Water hammer in elastic pipes

    International Nuclear Information System (INIS)

    Gale, J.; Tiselj, I.

    2002-01-01

    One dimensional two-fluid six-equation model of two-phase flow, that can be found in computer codes like RELAP5, TRAC, and CATHARE, was upgraded with additional terms, which enable modelling of the pressure waves in elastic pipes. It is known that pipe elasticity reduces the propagation velocity of the shock and other pressure waves in the piping systems. Equations that include the pipe elasticty terms are used in WAHA code, which is being developed within the WAHALoads project of 5't'h EU research program.(author)

  17. Elastic properties of ultrathin diamond/AlN membranes

    International Nuclear Information System (INIS)

    Zuerbig, V.; Hees, J.; Pletschen, W.; Sah, R.E.; Wolfer, M.; Kirste, L.; Heidrich, N.; Nebel, C.E.; Ambacher, O.; Lebedev, V.

    2014-01-01

    Nanocrystalline diamond- (NCD) and AlN-based ultrathin single layer and bilayer membranes are investigated towards their mechanical properties. It is shown that chemo-mechanical polishing and heavy boron doping of NCD thin films do not impact the elastic properties of NCD layers as revealed by negligible variations of the NCD Young's modulus (E). In addition, it is demonstrated that the combination of NCD elastic layer and AlN piezo-actuator is highly suitable for the fabrication of mechanically stable ultrathin membranes in comparison to AlN single layer membranes. The elastic parameters of NCD/AlN heterostructures are mainly determined by the outstanding high Young's modulus of NCD (E = 1019 ± 19 GPa). Such ultrathin unimorph membranes allow for fabrication of piezo-actuated AlN/NCD microlenses with tunable focus length. - Highlights: • Mechanical properties of nanocrystalline diamond (NCD) and AlN circular membranes • No influence of polishing of NCD thin films on the mechanical properties of NCD • No influence of heavy boron-doping on the mechanical properties of NCD • Demonstration of mechanically stable piezo-actuated NCD/AlN membranes • Reported performance of AlN/NCD microlenses with adjustable focus length

  18. The Photodynamic Bone Stabilization System: a minimally invasive, percutaneous intramedullary polymeric osteosynthesis for simple and complex long bone fractures

    Directory of Open Access Journals (Sweden)

    Vegt P

    2014-12-01

    Full Text Available Paul Vegt,1 Jeffrey M Muir,2 Jon E Block2 1Department of Surgery, Albert Schweitzer Hospital, Dordrecht, The Netherlands; 2The Jon Block Group, San Francisco, CA, USA Abstract: The treatment of osteoporotic long bone fractures is difficult due to diminished bone density and compromised biomechanical integrity. The majority of osteoporotic long bone fractures occur in the metaphyseal region, which poses additional problems for surgical repair due to increased intramedullary volume. Treatment with internal fixation using intramedullary nails or plating is associated with poor clinical outcomes in this patient population. Subsequent fractures and complications such as screw pull-out necessitate additional interventions, prolonging recovery and increasing health care costs. The Photodynamic Bone Stabilization System (PBSS is a minimally invasive surgical technique that allows clinicians to repair bone fractures using a light-curable polymer contained within an inflatable balloon catheter, offering a new treatment option for osteoporotic long bone fractures. The unique polymer compound and catheter application provides a customizable solution for long bone fractures that produces internal stability while maintaining bone length, rotational alignment, and postsurgical mobility. The PBSS has been utilized in a case series of 41 fractures in 33 patients suffering osteoporotic long bone fractures. The initial results indicate that the use of the light-cured polymeric rod for this patient population provides excellent fixation and stability in compromised bone, with a superior complication profile. This paper describes the clinical uses, procedural details, indications for use, and the initial clinical findings of the PBSS. Keywords: osteoporosis, long bone fracture, bone density, polymeric rod, orthopaedics, surgery

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

    Directory of Open Access Journals (Sweden)

    Tsukada Sachiyuki

    2012-07-01

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

  20. Intra-extramedullary drainage as an effective option for treatment of intramedullary ependymal cyst of thoracic spine: technical note.

    Science.gov (United States)

    Landi, Alessandro; Pietrantonio, Andrea; Marotta, Nicola; Mancarella, Cristina; Delfini, Roberto

    2014-03-01

    Intramedullary neuroepithelial cysts are extremely rare and only 15 cases have been reported in the literature. Clinico-radiological features are not indicative of a specific diagnosis; for this reason, diagnosis is based mainly on the histological features. In the literature, total surgical removal is considered the treatment of choice. The risk of recurrence is higher after partial removal and in cases of occlusion of intra-extramedullary shunt. For this reason, a surgical strategy that ensures the shunt patency in case of incomplete removal of the cyst becomes a very safe option for treatment of this pathology. We report the case of a 51-year-old woman who was found to have a dorsal (D9) intramedullary neuroepithelial cyst. She underwent surgical treatment with partial removal and placement of a Nelaton drainage device (8 French) inside the intra-extramedullary shunt. The patient experienced a complete regression of preoperative symptoms and magnetic resonance imaging (MRI) follow-up showed no radiological evidence of recurrence 24 months after surgical treatment. Spinal ependymal cysts show a high frequency of recurrence, especially in cases of partial removal of the cyst wall. Unfortunately, the cyst walls are often closely adherent to the spinal cord, making total removal impossible. Intra-extramedullary shunting is a viable option, although there is a high frequency of recurrence in cases of obstruction of the shunt. Placing an 8 Ch Nelaton drain between the dorsal columns is a reliable technique, especially in cases of partial removal. In fact, it allows continuous drainage of cyst fluid and subsequent resolution of symptoms, and it decreases the incidence of recurrences due to obstruction of the shunt. Georg Thieme Verlag KG Stuttgart · New York.

  1. Flexible omnidirectional carbon dioxide laser as an effective tool for resection of brainstem, supratentorial, and intramedullary cavernous malformations.

    Science.gov (United States)

    Choudhri, Omar; Karamchandani, Jason; Gooderham, Peter; Steinberg, Gary K

    2014-03-01

    Lasers have a long history in neurosurgery, yet bulky designs and difficult ergonomics limit their use. With its ease of manipulation and multiple applications, the OmniGuide CO2 laser has reintroduced laser technology to the microsurgical resection of brain and spine lesions. This laser, delivered through a hollow-core fiber lined with a unidirectional mirror, minimizes energy loss and allows precise targeting. To analyze resections performed by the senior author from April 2009 to March 2013 of 58 cavernous malformations (CMs) in the brain and spine with the use of the OmniGuide CO2 laser, to reflect on lessons learned from laser use in eloquent areas, and to share data on comparisons of laser power calibration and histopathology. Data were collected from electronic medical records, radiology reports, operative room records, OmniGuide CO2 laser case logs, and pathology records. Of 58 CMs, approximately 50% were in the brainstem (30) and the rest were in supratentorial (26) and intramedullary spinal locations (2). Fifty-seven, ranging from 5 to 45 mm, were resected, with a subtotal resection in 1. Laser power ranged from 2 to 10 W. Pathology specimens showed minimal thermal damage compared with traditionally resected specimens with bipolar coagulation. The OmniGuide CO2 laser is safe and has excellent precision for the resection of supratentorial, brainstem, and spinal intramedullary CMs. No laser-associated complications occurred, and very low energy was used to dissect malformations from their surrounding hemosiderin-stained parenchymas. The authors recommend its use for deep-seated and critically located CMs, along with traditional tools.

  2. The risk factors of perioperative hemoglobin and hematocrit drop after intramedullary nailing treatment for intertrochanteric fracture patients.

    Science.gov (United States)

    Wang, Jun; Wei, Jie; Wang, Manyi

    2015-01-01

    The objective of this study was to analyze the risk factors associated with the hemoglobin and hematocrit drops in the early postoperative period for intertrochanteric fracture patients with intramedullary nailing treatment. From January 2003 to December 2013, 634 intertrochanteric fracture patients with complete information were recruited into the study. Their age, gender, operating time, medical diseases, blood routine examination at admission and postoperative first day, and the days between the trauma and operation were recorded. The hemoglobin (HGB) change of patients (75 years) (P = 0.039). Meanwhile, the change of hematocrit (HCT) level of patients (75 years), but the difference was not significant (P = 0.062). The gender had no significant influence on HCT and HGB. The HGB and HCT change of patients with diabetes (ΔHCT, 8.47 ± 3.36 %; ΔHGB, 29.19 ± 13.10 g/l) were statistically greater than that of patients without diabetes (ΔHCT, 5.52 ± 3.84 %; ΔHGB, 19.81 ± 14.68 g/l) (P = 0.006, P = 0.022). The hypertension and coronary heart disease had no significant influence on the change of HCT and HGB levels. The operation time had a significant influence on the change of HCT and HGB. The ΔHCT and ΔHGB in the group for which the time was more than 48 h between the trauma and operation were greater than that in the group with less than 48 h between the trauma and operation but not significantly different (ΔHCT, P = 0.672; ΔHGB, P = 0.66). The factors of age, medical disease such as diabetes, operation time, and time between the trauma and operation may be associated with the change of perioperative hemoglobin and hematocrit levels for intertrochanteric fracture patients after intramedullary nailing treatment in the early postoperative period.

  3. Elastic coupling of limb joints enables faster bipedal walking

    Science.gov (United States)

    Dean, J.C.; Kuo, A.D.

    2008-01-01

    The passive dynamics of bipedal limbs alone are sufficient to produce a walking motion, without need for control. Humans augment these dynamics with muscles, actively coordinated to produce stable and economical walking. Present robots using passive dynamics walk much slower, perhaps because they lack elastic muscles that couple the joints. Elastic properties are well known to enhance running gaits, but their effect on walking has yet to be explored. Here we use a computational model of dynamic walking to show that elastic joint coupling can help to coordinate faster walking. In walking powered by trailing leg push-off, the model's speed is normally limited by a swing leg that moves too slowly to avoid stumbling. A uni-articular spring about the knee allows faster but uneconomical walking. A combination of uni-articular hip and knee springs can speed the legs for improved speed and economy, but not without the swing foot scuffing the ground. Bi-articular springs coupling the hips and knees can yield high economy and good ground clearance similar to humans. An important parameter is the knee-to-hip moment arm that greatly affects the existence and stability of gaits, and when selected appropriately can allow for a wide range of speeds. Elastic joint coupling may contribute to the economy and stability of human gait. PMID:18957360

  4. Predictors of intramedullary lesion expansion rate on MR images of patients with subaxial spinal cord injury.

    Science.gov (United States)

    Le, Elizabeth; Aarabi, Bizhan; Hersh, David S; Shanmuganathan, Kathirkamanthan; Diaz, Cara; Massetti, Jennifer; Akhtar-Danesh, Noori

    2015-06-01

    OBJECT Studies of preclinical spinal cord injury (SCI) in rodents indicate that expansion of intramedullary lesions (IMLs) seen on MR images may be amenable to neuroprotection. In patients with subaxial SCI and motor-complete American Spinal Injury Association (ASIA) Impairment Scale (AIS) Grade A or B, IML expansion has been shown to be approximately 900 μm/hour. In this study, the authors investigated IML expansion in a cohort of patients with subaxial SCI and AIS Grade A, B, C, or D. METHODS Seventy-eight patients who had at least 2 MRI scans within 6 days of SCI were enrolled. Data were analyzed by regression analysis. RESULTS In this cohort, the mean age was 45.3 years (SD 18.3 years), 73 patients were injured in a motor vehicle crash, from a fall, or in sport activities, and 77% of them were men. The mean Injury Severity Score (ISS) was 26.7 (SD 16.7), and the AIS grade was A in 23 patients, B in 7, C in 7, and D in 41. The mechanism of injury was distraction in 26 patients, compression in 22, disc/osteophyte complex in 29, and Chance fracture in 1. The mean time between injury onset and the first MRI scan (Interval 1) was 10 hours (SD 8.7 hours), and the mean time to the second MRI scan (Interval 2) was 60 hours (SD 29.6 hours). The mean IML lengths of the first and second MR images were 38.8 mm (SD 20.4 mm) and 51 mm (SD 36.5 mm), respectively. The mean time from the first to the second MRI scan (Interval 3) was 49.9 hours (SD 28.4 hours), and the difference in IML lengths was 12.6 mm (SD 20.7 mm), reflecting an expansion rate of 366 μm/ hour (SD 710 μm/hour). IML expansion in patients with AIS Grades A and B was 918 μm/hour (SD 828 μm/hour), and for those with AIS Grades C and D, it was 21 μm/hour (SD 304 μm/hour). Univariate analysis indicated that AIS Grade A or B versus Grades C or D (p < 0.0001), traction (p= 0.0005), injury morphology (p < 0.005), the surgical approach (p= 0.009), vertebral artery injury (p= 0.02), age (p < 0.05), ISS (p < 0

  5. [Intramedullary nailing of the distal tibia illustrated with the Expert(TM) tibia nail].

    Science.gov (United States)

    El Attal, R; Hansen, M; Rosenberger, R; Smekal, V; Rommens, P M; Blauth, M

    2011-12-01

    multicenter study. The follow-up rate was 81% after 1 year. Of these, 91 fractures (50.6%) were located in the distal third of the tibia. In this segment, the rate of delayed union was 10.6%. Malalignment of > 5° was observed in 5.4%. A secondary malalignment after initial good reduction was detected in only 1.1% of all cases. The implant-specific risk for screw breakage was 3.2%. One patient sustained a deep infection. If additional fibula plating was performed an 8-fold higher risk for delayed bone healing was observed (95%CI: 2.9-21.2, pfracture of the fibula was at the same height as on the tibia, the risk for delayed healing was even 14-fold (95% CI: 3.4-62.5, pfractures treated with an intramedullary nail. Using the ETN with its optimized locking options, fibula plating is not recommended, thus, avoiding soft tissue problems and potentially delayed bone healing.

  6. Uses of stable isotopes

    International Nuclear Information System (INIS)

    Axente, Damian

    1998-01-01

    The most important fields of stable isotope use with examples are presented. These are: 1. Isotope dilution analysis: trace analysis, measurements of volumes and masses; 2. Stable isotopes as tracers: transport phenomena, environmental studies, agricultural research, authentication of products and objects, archaeometry, studies of reaction mechanisms, structure and function determination of complex biological entities, studies of metabolism, breath test for diagnostic; 3. Isotope equilibrium effects: measurement of equilibrium effects, investigation of equilibrium conditions, mechanism of drug action, study of natural processes, water cycle, temperature measurements; 4. Stable isotope for advanced nuclear reactors: uranium nitride with 15 N as nuclear fuel, 157 Gd for reactor control. In spite of some difficulties of stable isotope use, particularly related to the analytical techniques, which are slow and expensive, the number of papers reporting on this subject is steadily growing as well as the number of scientific meetings organized by International Isotope Section and IAEA, Gordon Conferences, and regional meeting in Germany, France, etc. Stable isotope application development on large scale is determined by improving their production technologies as well as those of labeled compound and the analytical techniques. (author)

  7. Calcium stable isotope geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gausonne, Nikolaus [Muenster Univ. (Germany). Inst. fuer Mineralogie; Schmitt, Anne-Desiree [Strasbourg Univ. (France). LHyGeS/EOST; Heuser, Alexander [Bonn Univ. (Germany). Steinmann-Inst. fuer Geologie, Mineralogie und Palaeontologie; Wombacher, Frank [Koeln Univ. (Germany). Inst. fuer Geologie und Mineralogie; Dietzel, Martin [Technische Univ. Graz (Austria). Inst. fuer Angewandte Geowissenschaften; Tipper, Edward [Cambridge Univ. (United Kingdom). Dept. of Earth Sciences; Schiller, Martin [Copenhagen Univ. (Denmark). Natural History Museum of Denmark

    2016-08-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  8. Calcium stable isotope geochemistry

    International Nuclear Information System (INIS)

    Gausonne, Nikolaus; Schmitt, Anne-Desiree; Heuser, Alexander; Wombacher, Frank; Dietzel, Martin; Tipper, Edward; Schiller, Martin

    2016-01-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  9. Nonlinear theory of elastic shells

    International Nuclear Information System (INIS)

    Costa Junior, J.A.

    1979-08-01

    Nonlinear theory of elastic shells is developed which incorporates both geometric and physical nonlinearities and which does not make use of the well known Love-Kirchhoff hypothesis. The resulting equations are formulated in tensorial notation and are reduced to the ones of common use when simplifying assumptions encountered in the especific litterature are taken. (Author) [pt

  10. Heart transplantation and arterial elasticity

    Directory of Open Access Journals (Sweden)

    Colvin-Adams M

    2013-12-01

    Full Text Available Monica Colvin-Adams,1 Nonyelum Harcourt,1 Robert LeDuc,2 Ganesh Raveendran,1 Yassir Sonbol,3 Robert Wilson,1 Daniel Duprez11Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA; 2Division of Biostatistics University of Minnesota, Minneapolis, MN, USA; 3Cardiovascular Division, St Luke's Hospital System, Sugar Land, TX, USAObjective: Arterial elasticity is a functional biomarker that has predictive value for cardiovascular morbidity and mortality in nontransplant populations. There is little information regarding arterial elasticity in heart transplant recipients. This study aimed to characterize small (SAE and large (LAE artery elasticity in heart transplant recipients in comparison with an asymptomatic population free of overt cardiovascular disease. A second goal was to identify demographic and clinical factors associated with arterial elasticity in this unique population.Methods: Arterial pulse waveform was registered noninvasively at the radial artery in 71 heart transplant recipients between 2008 and 2010. SAEs and LAEs were derived from diastolic pulse contour analysis. Comparisons were made to a healthy cohort of 1,808 participants selected from our prevention clinic database. Multiple regression analyses were performed to evaluate associations between risk factors and SAE and LAE within the heart transplant recipients.Results: LAE and SAE were significantly lower in heart transplant recipients than in the normal cohort (P <0.01 and P < 0.0001, respectively. Female sex and history of ischemic cardiomyopathy were significantly associated with reduced LAE and SAE. Older age and the presence of moderate cardiac allograft vasculopathy were also significantly associated with reduced SAE. Transplant duration was associated with increased SAE.Conclusion: Heart transplants are associated with peripheral endothelial dysfunction and arterial stiffness, as demonstrated by a significant reduction in SAE and LAE when compared with a

  11. Collusion and the elasticity of demand

    OpenAIRE

    David Collie

    2004-01-01

    The analysis of collusion in infinitely repeated Cournot oligopoly games has generally assumed that demand is linear, but this note uses constant-elasticity demand functions to investigate how the elasticity of demand affects the sustainability of collusion.

  12. Mechanical behaviour of nanoparticles: Elasticity and plastic ...

    Indian Academy of Sciences (India)

    2015-06-03

    Jun 3, 2015 ... Mechanical behaviour of nanoparticles: Elasticity and plastic deformation mechanisms ... The main results in terms of elasticity and plastic deformation mechanisms are then reported ... Pramana – Journal of Physics | News.

  13. Stable isotope studies

    International Nuclear Information System (INIS)

    Ishida, T.

    1992-01-01

    The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs

  14. Interactive Stable Ray Tracing

    DEFF Research Database (Denmark)

    Dal Corso, Alessandro; Salvi, Marco; Kolb, Craig

    2017-01-01

    Interactive ray tracing applications running on commodity hardware can suffer from objectionable temporal artifacts due to a low sample count. We introduce stable ray tracing, a technique that improves temporal stability without the over-blurring and ghosting artifacts typical of temporal post-pr...

  15. The Stable Concordance Genus

    OpenAIRE

    Kearney, M. Kate

    2013-01-01

    The concordance genus of a knot is the least genus of any knot in its concordance class. Although difficult to compute, it is a useful invariant that highlights the distinction between the three-genus and four-genus. In this paper we define and discuss the stable concordance genus of a knot, which describes the behavior of the concordance genus under connected sum.

  16. Stable radiographic scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    Stable compositions which are useful in the preparation of Technetium-99m-based scintigraphic agents are discussed. They are comprised of ascorbic acid or a pharmaceutically acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in oxidized pertechnetate-99m (sup(99m)TcO 4 - ) solution

  17. Some stable hydromagnetic equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J L; Oberman, C R; Kulsrud, R M; Frieman, E A [Project Matterhorn, Princeton University, Princeton, NJ (United States)

    1958-07-01

    We have been able to find and investigate the properties of equilibria which are hydromagnetically stable. These equilibria can be obtained, for example, by wrapping conductors helically around the stellarator tube. Systems with I = 3 or 4 are indicated to be optimum for stability purposes. In some cases an admixture of I = 2 fields can be advantageous for achieving equilibrium. (author)

  18. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2016-01-01

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  19. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2016-09-06

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  20. Management of knee rheumatoid arthritis and tibia nonunion with one-stage total knee arthroplasty and intramedullary nailing: A report of two cases

    Directory of Open Access Journals (Sweden)

    Fahri Erdogan

    2018-01-01

    Full Text Available Total knee arthroplasty (TKA is a surgical procedure which is widely used in the treatment of gonarthrosis secondary to rheumatoid arthritis (RA. The incidence of stress fractures in tibia in the patients with RA is higher compared to normal patients. In this study, we report two cases of TKA and intramedullary nailing in RA patients with severe knee arthritis and tibial nonunion. Both patients had a satisfactory clinical outcome with radiological healing of the tibial fracture.

  1. Staged protocol for the treatment of chronic femoral shaft osteomyelitis with Ilizarov's technique followed by the use of intramedullary locked nail

    Directory of Open Access Journals (Sweden)

    Po-Hsin Chou

    2017-06-01

    Conclusion: In the treatment of chronic femur osteomyelitis, the staged protocol of Ilizarov distraction osteogenesis followed by intramedullary nailing was safe and successful, and allowed for union, realignment, reorientation, and leg-length restoration. With regard to the soft tissue, this technique provides a unique type of reconstructive closure for infected wounds. It is suggested that the staged protocol is reliable in providing successful simultaneous reconstruction for bone and soft tissue defects without flap coverage.

  2. Thermodynamic parameters of elasticity and electrical conductivity ...

    African Journals Online (AJOL)

    The thermodynamic parameters (change in free energy of elasticity, DGe; change in enthalpy of elasticity, DHe; and change in entropy of elasticity, DSe) and the electrical conductivity of natural rubber composites reinforced separately with some agricultural wastes have been determined. Results show that the reinforced ...

  3. On Elasticity Measurement in Cloud Computing

    Directory of Open Access Journals (Sweden)

    Wei Ai

    2016-01-01

    Full Text Available Elasticity is the foundation of cloud performance and can be considered as a great advantage and a key benefit of cloud computing. However, there is no clear, concise, and formal definition of elasticity measurement, and thus no effective approach to elasticity quantification has been developed so far. Existing work on elasticity lack of solid and technical way of defining elasticity measurement and definitions of elasticity metrics have not been accurate enough to capture the essence of elasticity measurement. In this paper, we present a new definition of elasticity measurement and propose a quantifying and measuring method using a continuous-time Markov chain (CTMC model, which is easy to use for precise calculation of elasticity value of a cloud computing platform. Our numerical results demonstrate the basic parameters affecting elasticity as measured by the proposed measurement approach. Furthermore, our simulation and experimental results validate that the proposed measurement approach is not only correct but also robust and is effective in computing and comparing the elasticity of cloud platforms. Our research in this paper makes significant contribution to quantitative measurement of elasticity in cloud computing.

  4. Elastic nailing of tibia shaft fractures in young children up to 10 years of age.

    Science.gov (United States)

    Heo, Jeong; Oh, Chang-Wug; Park, Kyeong-Hyeon; Kim, Joon-Woo; Kim, Hee-June; Lee, Jong-Chul; Park, Il-Hyung

    2016-04-01

    Although tibia shaft fractures in children usually have satisfactory results after closed reduction and casting, there are several surgical indications, including associated fractures and soft tissue injuries such as open fractures. Titanium elastic nails (TENs) are often used for pediatric tibia fractures, and have the advantage of preserving the open physis. However, complications such as delayed union or nonunion are not uncommon in older children or open fractures. In the present study, we evaluated children up to 10 years of age with closed or open tibial shaft fractures treated with elastic nailing technique. A total of 16 tibia shaft fractures treated by elastic nailing from 2001 to 2013 were reviewed. The mean patient age at operation was 7 years (range: 5-10 years). Thirteen of 16 cases were open fractures (grade I: 4, grade II: 6, grade IIIA: 3 cases); the other cases had associated fractures that necessitated operative treatments. Closed, antegrade intramedullary nailing was used to insert two nails through the proximal tibial metaphysis. All patients were followed up for at least one year after the injury. Outcomes were evaluated using modified Flynn's criteria, including union, alignment, leg length discrepancies, and complications. All fractures achieved union a mean of 16.1 weeks after surgery (range: 11-26 weeks). No patient reported knee pain or experienced any loss of knee or ankle motion. There was a case of superficial infection in a patient with grade III open fracture. Three patients reported soft tissue discomfort due to prominent TEN tips at the proximal insertion site, which required cutting the tip before union or removing the nail after union. At the last follow-up, there were no angular or rotational deformities over 10° in either the sagittal or coronal planes. With the exception of one case with an overgrowth of 15 mm, no patient showed shortening or overgrowth exceeding 10mm. Among final outcomes, 15 were excellent and 1 was

  5. Mating of a PROSTALAC spacer with an intramedullary nail for reconstruction of an infected interprosthetic femoral shaft fracture: a case report.

    Science.gov (United States)

    Kamath, Atul F; Austin, Daniel; Lee, Gwo-Chin

    2012-08-01

    Reconstruction for concurrent infection of an ipsilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA) is a challenge. We report a 2-stage reconstruction of a THA for chronic infection of both the THA and TKA with severe femoral bone loss secondary to interprosthetic fractures. The reconstruction involved using a custom-made, temporary, antibiotic-impregnated PROSTALAC spacer mated with an intramedullary nail. The acetabulum was then exposed and the necrotic cartilage was removed and curetted. The acetabulum was reamed to accept a PROSTALAC acetabular shell. The shell was cemented into the acetabulum with antibiotic cement. The custom-made spacer was then inserted distally first into the tibia. The distal end of the intramedullary nail was interlocked with a bicortical bolt to minimise nail rotation. Antibiotic-impregnated cement was moulded around the nail and spacer. The proximal end of the spacer was then reduced into the acetabular socket, and the joint was irrigated and the wound closed. A customised abduction brace was fitted, and partial weight bearing was allowed. Sufficient leg length, soft-tissue tension, and range of hip motion were restored, and a total femur and constrained liner was re-implanted 4 months later. Mating of an intramedullary nail with a PROSTALAC spacer is a viable reconstructive option.

  6. Spinal cord edema with contrast enhancement mimicking intramedullary tumor in patient with cervical myelopathy: A case report and a brief literature review.

    Science.gov (United States)

    Gkasdaris, Grigorios; Chourmouzi, Danai; Karagiannidis, Apostolos; Kapetanakis, Stylianos

    2017-01-01

    Cervical myelopathy (CM) is a clinical diagnosis that may be associated with hyperintense areas on T2-weighted magnetic resonance imaging (MRI) scan. The use of contrast enhancement in such areas to differentiate between neoplastic and degenerative disease has rarely been described. We present a 41-year-old female with a 5-month course of progressive CM. The cervical MRI revealed spinal cord swelling, stenosis, and a hyperintense signal at the C5-C6 and C5-C7 levels. Both the neurologic and radiologic examinations were consistent with an intramedullary cervical cord tumor. To decompress the spinal canal, an anterior cervical discectomy and fusion was performed from C5 to C7 level. This resulted in immediate and significant improvement of the myelopathy. Postoperatively, over 1.5 years, the hyperintense, enhancing intramedullary lesion gradually regressed on multiple postoperative MRI scans. Spinal cord edema is occasionally seen on MR studies of the cervical spine in patients with degenerative CM. Contrast-enhanced MR studies may help differentiate hyperintense cord signals due to edema vs. atypical intramedullary tumors. Routine successive postoperative MRI evaluations are crucial to confirm the diagnosis of degenerative vs. neoplastic disease.

  7. Short-Term Radiographic Outcome After Distal Chevron Osteotomy for Hallux Valgus Using Intramedullary Plates With an Amended Algorithm for the Surgical Management of Hallux Valgus.

    Science.gov (United States)

    Matsumoto, Takumi; Gross, Christopher E; Parekh, Selene G

    2018-03-01

    Distal Chevron osteotomy is a well-established surgical procedure for mild to moderate hallux valgus deformity. Many methods have been described for fixation of osteotomy site; secure fixation, enabling large displacement of the metatarsal head, is one of the essentials of this procedure. The purpose of the present study was to evaluate the short-term radiographic outcome of a distal Chevron osteotomy using an intramedullary plate for the correction of hallux valgus deformity. The present study evaluated 37 patients (40 feet) who underwent distal Chevron osteotomy using an intramedullary plate by periodic radiographs obtained preoperatively and at 4 weeks, 8 weeks, 3 months, and 6 months postoperatively. Correction of the hallux valgus angle averaged 17.8°, intermetatarsal angle 7.4°, distal metatarsal articular angle 2.7°, and sesamoid position 1.4 stages at 3 months postoperatively. The average lateral shift of the capital fragment was 6.5 mm. All patients achieved bone union, and there were no cases of dislocation, displacement, or avascular necrosis of the metatarsal head fragment. In conclusion, a distal Chevron osteotomy using an intramedullary plate was a favorable method for the correction of mild to moderate hallux valgus deformity. Level IV: Case series.

  8. Thermally stable diamond brazing

    Science.gov (United States)

    Radtke, Robert P [Kingwood, TX

    2009-02-10

    A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

  9. [Study on elasticity of medical service demand at the township level in China].

    Science.gov (United States)

    Shi, Hong-xing; Lv, Jun; Xie, Yi-ping; Wang, Ying; Jia, Jin-zhong; Chang, Feng-shui; Duan, Lin; Sun, Mei; Wang, Zhi-feng; Hao, Mo

    2010-06-18

    To find out the economic laws regulating medical service demand in accordance with influencing factors at the township level, thus to provide references for further adjusting the medical service demand reasonably in the future. The model of medical service demand was established to measure the elasticity of demand in 49 township health clinics in 1995, 1999, 2003 and 2007. The price elasticity of outpatient and inpatient demand was stable during the four periods, and the average value was -0.029 and -0.132 respectively; the average value of income elasticity was 0.973 and 0.977, registering a downward trend in general. The medical service demand at the township level is price inelastic, indicating that it is a necessity for rural residents. The downward trend of income elasticity under the influence of some health policies illustrates a lightening in economic burden for medical service demand among rural residents in township health clinics.

  10. Cellular automaton and elastic net for event reconstruction in the NEMO-2 experiment

    International Nuclear Information System (INIS)

    Kovalenko, V.

    1997-01-01

    A cellular automaton for track searching and an elastic net for charged particle trajectory fitting are presented. The advantages of the methods are: simplicity of the algorithms, fast and stable convergence to real tracks, and a reconstruction efficiency close to 100%. Demonstration programs are available at http://nuweb.jinr.dubna.su/LNP/NEMO using a Java enabled browser. (orig.)

  11. Elasticity of Relativistic Rigid Bodies?

    Science.gov (United States)

    Smarandache, Florentin

    2013-10-01

    In the classical Twin Paradox, according to the Special Theory of Relativity, when the traveling twin blasts off from the Earth to a relative velocity v =√{/3 } 2 c with respect to the Earth, his measuring stick and other physical objects in the direction of relative motion shrink to half their lengths. How is that possible in the real physical world to have let's say a rigid rocket shrinking to half and then later elongated back to normal as an elastic material when it stops? What is the explanation for the traveler's measuring stick and other physical objects, in effect, return to the same length to their original length in the Stay-At-Home, but there is no record of their having shrunk? If it's a rigid (not elastic) object, how can it shrink and then elongate back to normal? It might get broken in such situation.

  12. Elasticity of Long Distance Travelling

    DEFF Research Database (Denmark)

    Knudsen, Mette Aagaard

    2011-01-01

    With data from the Danish expenditure survey for 12 years 1996 through 2007, this study analyses household expenditures for long distance travelling. Household expenditures are examined at two levels of aggregation having the general expenditures on transportation and leisure relative to five other...... aggregated commodities at the highest level, and the specific expenditures on plane tickets and travel packages at the lowest level. The Almost Ideal Demand System is applied to determine the relationship between expenditures on transportation and leisure and all other purchased non-durables within...... packages has higher income elasticity of demand than plane tickets but also higher than transportation and leisure in general. The findings within price sensitiveness are not as sufficient estimated, but the model results indicate that travel packages is far more price elastic than plane tickets which...

  13. Pipeline robots with elastic elements

    Directory of Open Access Journals (Sweden)

    A. Matuliauskas

    2002-10-01

    Full Text Available In the article constructions of the pipeline robots with elastic elements are reviewed and the scheme of new original construction is presented. The mathematical models of a robot with one-dimensional vibration exciter with two degrees of freedom were developed and the equations of movement were formed and written. The mathematical model of the pipeline robot with circular elements is formed and its motion equations are presented.

  14. The poverty elasticity of growth

    OpenAIRE

    Heltberg, Rasmus

    2002-01-01

    How much does economic growth contribute to poverty reduction? I discuss analytical and empirical approches to assess the poverty elasticity of growth, and emphasize that the relationship between growth and poverty change is non-constant. For a given poverty measure, it depends on initial inequality and on the location of the poverty line relative to mean income. In most cases, growth is more important for poverty reduction than changes in inequality, but this does not tender inequality unimp...

  15. Transient waves in visco-elastic media

    CERN Document Server

    Ricker, Norman

    1977-01-01

    Developments in Solid Earth Geophysics 10: Transient Waves in Visco-Elastic Media deals with the propagation of transient elastic disturbances in visco-elastic media. More specifically, it explores the visco-elastic behavior of a medium, whether gaseous, liquid, or solid, for very-small-amplitude disturbances. This volume provides a historical overview of the theory of the propagation of elastic waves in solid bodies, along with seismic prospecting and the nature of seismograms. It also discusses the seismic experiments, the behavior of waves propagated in accordance with the Stokes wave

  16. Teaching nonlinear dynamics through elastic cords

    International Nuclear Information System (INIS)

    Chacon, R; Galan, C A; Sanchez-Bajo, F

    2011-01-01

    We experimentally studied the restoring force of a length of stretched elastic cord. A simple analytical expression for the restoring force was found to fit all the experimental results for different elastic materials. Remarkably, this analytical expression depends upon an elastic-cord characteristic parameter which exhibits two limiting values corresponding to two nonlinear springs with different Hooke's elastic constants. Additionally, the simplest model of elastic cord dynamics is capable of exhibiting a great diversity of nonlinear phenomena, including bifurcations and chaos, thus providing a suitable alternative model system for discussing the basic essentials of nonlinear dynamics in the context of intermediate physics courses at university level.

  17. Elastic interaction between surface and spherical pore

    International Nuclear Information System (INIS)

    Ganeev, G.Z.; Kadyrzhanov, K.K.; Kislitsyn, S.B.; Turkebaev, T.Eh.

    2000-01-01

    The energy of elastic interaction of a gas-filled spherical cavity with a boundary of an elastic isotropic half-space is determined. The elastic field of a system of a spherical cavity - boundary is represented as an expansion in series of potential functions. The factors of expansions are determined by boundary conditions on a free surface of an elastic half-space and on a spherical surface of a cavity with pressure of gas P. Function of a Tresca-Miesesa on a surface of elastic surface is defined additionally with purpose creep condition determination caused by gas pressure in the cavity. (author)

  18. Elastic scattering at the LHC

    CERN Document Server

    Kaspar, Jan; Deile, M

    The seemingly simple elastic scattering of protons still presents a challenge for the theory. In this thesis we discuss the elastic scattering from theoretical as well as experimental point of view. In the theory part, we present several models and their predictions for the LHC. We also discuss the Coulomb-hadronic interference, where we present a new eikonal calculation to all orders of alpha, the fine-structure constant. In the experimental part we introduce the TOTEM experiment which is dedicated, among other subjects, to the measurement of the elastic scattering at the LHC. This measurement is performed primarily with the Roman Pot (RP) detectors - movable beam-pipe insertions hundreds of meters from the interaction point, that can detect protons scattered to very small angles. We discuss some aspects of the RP simulation and reconstruction software. A central point is devoted to the techniques of RP alignment - determining the RP sensor positions relative to each other and to the beam. At the end we pres...

  19. Biomimetic heterogenous elastic tissue development.

    Science.gov (United States)

    Tsai, Kai Jen; Dixon, Simon; Hale, Luke Richard; Darbyshire, Arnold; Martin, Daniel; de Mel, Achala

    2017-01-01

    There is an unmet need for artificial tissue to address current limitations with donor organs and problems with donor site morbidity. Despite the success with sophisticated tissue engineering endeavours, which employ cells as building blocks, they are limited to dedicated labs suitable for cell culture, with associated high costs and long tissue maturation times before available for clinical use. Direct 3D printing presents rapid, bespoke, acellular solutions for skull and bone repair or replacement, and can potentially address the need for elastic tissue, which is a major constituent of smooth muscle, cartilage, ligaments and connective tissue that support organs. Thermoplastic polyurethanes are one of the most versatile elastomeric polymers. Their segmented block copolymeric nature, comprising of hard and soft segments allows for an almost limitless potential to control physical properties and mechanical behaviour. Here we show direct 3D printing of biocompatible thermoplastic polyurethanes with Fused Deposition Modelling, with a view to presenting cell independent in-situ tissue substitutes. This method can expeditiously and economically produce heterogenous, biomimetic elastic tissue substitutes with controlled porosity to potentially facilitate vascularisation. The flexibility of this application is shown here with tubular constructs as exemplars. We demonstrate how these 3D printed constructs can be post-processed to incorporate bioactive molecules. This efficacious strategy, when combined with the privileges of digital healthcare, can be used to produce bespoke elastic tissue substitutes in-situ, independent of extensive cell culture and may be developed as a point-of-care therapy approach.

  20. Stable isotope analysis

    International Nuclear Information System (INIS)

    Tibari, Elghali; Taous, Fouad; Marah, Hamid

    2014-01-01

    This report presents results related to stable isotopes analysis carried out at the CNESTEN DASTE in Rabat (Morocco), on behalf of Senegal. These analyzes cover 127 samples. These results demonstrate that Oxygen-18 and Deuterium in water analysis were performed by infrared Laser spectroscopy using a LGR / DLT-100 with Autosampler. Also, the results are expressed in δ values (‰) relative to V-SMOW to ± 0.3 ‰ for oxygen-18 and ± 1 ‰ for deuterium.

  1. Forensic Stable Isotope Biogeochemistry

    Science.gov (United States)

    Cerling, Thure E.; Barnette, Janet E.; Bowen, Gabriel J.; Chesson, Lesley A.; Ehleringer, James R.; Remien, Christopher H.; Shea, Patrick; Tipple, Brett J.; West, Jason B.

    2016-06-01

    Stable isotopes are being used for forensic science studies, with applications to both natural and manufactured products. In this review we discuss how scientific evidence can be used in the legal context and where the scientific progress of hypothesis revisions can be in tension with the legal expectations of widely used methods for measurements. Although this review is written in the context of US law, many of the considerations of scientific reproducibility and acceptance of relevant scientific data span other legal systems that might apply different legal principles and therefore reach different conclusions. Stable isotopes are used in legal situations for comparing samples for authenticity or evidentiary considerations, in understanding trade patterns of illegal materials, and in understanding the origins of unknown decedents. Isotope evidence is particularly useful when considered in the broad framework of physiochemical processes and in recognizing regional to global patterns found in many materials, including foods and food products, drugs, and humans. Stable isotopes considered in the larger spatial context add an important dimension to forensic science.

  2. Motivation and compliance with intraoral elastics.

    Science.gov (United States)

    Veeroo, Helen J; Cunningham, Susan J; Newton, Jonathon Timothy; Travess, Helen C

    2014-07-01

    Intraoral elastics are commonly used in orthodontics and require regular changing to be effective. Unfortunately, poor compliance with elastics is often encountered, especially in adolescents. Intention for an action and its implementation can be improved using "if-then" plans that spell out when, where, and how a set goal, such as elastic wear, can be put into action. Our aim was to determine the effect of if-then plans on compliance with elastics. To identify common barriers to compliance with recommendations concerning elastic wear, semistructured interviews were carried out with 14 adolescent orthodontic patients wearing intraoral elastics full time. Emerging themes were used to develop if-then plans to improve compliance with elastic wear. A prospective pilot study assessed the effectiveness of if-then planning aimed at overcoming the identified barriers on compliance with elastic wear. Twelve participants were randomized equally into study and control groups; the study group received information about if-then planning. The participants were asked to collect used elastics, and counts of these were used to assess compliance. A wide range of motivational and volitional factors were described by the interviewed participants, including the perceived benefits of elastics, cues to remember, pain, eating, social situations, sports, loss of elastics, and breakages. Compliance with elastic wear was highly variable among patients. The study group returned more used elastics, suggesting increased compliance, but the difference was not significant. The use of if-then plans might improve compliance with elastic wear when compared with routine clinical instructions. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  3. What U.S. data should be used to measure the price elasticity of demand for alcohol?

    Science.gov (United States)

    Ruhm, Christopher J; Jones, Alison Snow; McGeary, Kerry Anne; Kerr, William C; Terza, Joseph V; Greenfield, Thomas K; Pandian, Ravi S

    2012-12-01

    This paper examines how estimates of the price elasticity of demand for beer vary with the choice of alcohol price series examined. Our most important finding is that the commonly used ACCRA price data are unlikely to reliably indicate alcohol demand elasticities-estimates obtained from this source vary drastically and unpredictably. As an alternative, researchers often use beer taxes to proxy for alcohol prices. While the estimated beer taxes elasticities are more stable, there are several problems with using taxes, including difficulties in accounting for cross-price effects. We believe that the most useful estimates reported in this paper are obtained using annual Uniform Product Code (UPC) "barcode" scanner data on grocery store alcohol prices. These estimates suggest relatively low demand elasticity, probably around -0.3, with evidence that the elasticities are considerably overstated in models that control for beer but not wine or spirits prices. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Finite element analysis of intramedullary nailing and double locking plate for treating extra-articular proximal tibial fractures.

    Science.gov (United States)

    Chen, Fancheng; Huang, Xiaowei; Ya, Yingsun; Ma, Fenfen; Qian, Zhi; Shi, Jifei; Guo, Shuolei; Yu, Baoqing

    2018-01-16

    Proximal tibia fractures are one of the most familiar fractures. Surgical approaches are usually needed for anatomical reduction. However, no single treatment method has been widely established as the standard care. Our present study aims to compare the stress and stability of intramedullary nails (IMN) fixation and double locking plate (DLP) fixation in the treatment of extra-articular proximal tibial fractures. A three-dimensional (3D) finite element model of the extra-articular proximal tibial fracture, whose 2-cm bone gap began 7 cm from the tibial plateau articular surface, was created fixed by different fixation implants. The axial compressive load on an adult knee during single-limb stance was imitated by an axial force of 2500 N with a distribution of 60% to the medial compartment, while the distal end was fixed effectively. The equivalent von Mises stress and displacement of the model was used as the output measures for analysis. The maximal equivalent von Mises stress value of the system in the IMN model was 293.23 MPa, which was higher comparing against that in the DLP fixation model (147.04 MPa). And the mean stress of the model in the IMN model (9.25 MPa) was higher than that of the DLP fixation system in terms of equivalent von Mises stress (EVMS) (P tibial fractures of young patients.

  5. Percutaneous clamping of spiral and oblique fractures of the tibial shaft: a safe and effective reduction aid during intramedullary nailing.

    Science.gov (United States)

    Collinge, Cory A; Beltran, Michael J; Dollahite, Henry A; Huber, Florian G

    2015-06-01

    The reduction of tibial shaft fractures during intramedullary nailing is important if limb alignment is to be restored and successful clinical outcomes are expected. We have used a percutaneously applied (or open) clamp or clamps to achieve and maintain reduction during nailing of all amendable tibial shaft fractures. In this article, we describe the technique and preliminary results comparing closed, simple spiral and oblique tibial shaft fractures (OTA 42-A1 and A2) managed with percutaneous clamp-assisted nailing (CAN) versus nailing using manual reduction (MRN) held by the surgical team. In the MRN group, there were an increased fracture gap (P = 0.04) and trends toward malalignment (P = 0.07) and healing time (P = 0.06) compared with the CAN group. There were also trends in clinical; no wound complications occurred in either group. We have found that percutaneous CAN of closed, simple spiral and oblique tibial shaft fractures seems safe and allows for early predictable union with reproducible alignment compared with nailing using MRN.

  6. A patient specific finite element simulation of intramedullary nailing to predict the displacement of the distal locking hole.

    Science.gov (United States)

    Mortazavi, Javad; Farahmand, Farzam; Behzadipour, Saeed; Yeganeh, Ali; Aghighi, Mohammad

    2018-05-01

    Distal locking is a challenging subtask of intramedullary nailing fracture fixation due to the nail deformation that makes the proximally mounted targeting systems ineffective. A patient specific finite element model was developed, based on the QCT data of a cadaveric femur, to predict the position of the distal hole of the nail postoperatively. The mechanical interactions of femur and nail (of two sizes) during nail insertion was simulated using ABAQUS in two steps of dynamic pushing and static equilibrium, for the intact and distally fractured bone. Experiments were also performed on the same specimen to validate the simulation results. A good agreement was found between the model predictions and the experimental observations. There was a three-point contact pattern between the nail and medullary canal, only on the proximal fragment of the fractured bone. The nail deflection was much larger in the sagittal plane and increased for the larger diameter nail, as well as for more distally fractured or intact femur. The altered position of the distal hole was predicted by the model with an acceptable error (mean: 0.95; max: 1.5 mm, in different tests) to be used as the compensatory information for fine tuning of proximally mounted targeting systems. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.

  7. 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.

  8. Removal of a Broken Cannulated Intramedullary Nail: Review of the Literature and a Case Report of a New Technique

    Directory of Open Access Journals (Sweden)

    Amr A. Abdelgawad

    2013-01-01

    Full Text Available Nonunion of long bones fixed with nails may result in implant failure. Removal of a broken intramedullary nail may be a real challenge. Many methods have been described to allow for removal of the broken piece of the nail. In this paper, we are reviewing the different techniques to extract a broken nail, classifying them into different subsets, and describing a new technique that we used to remove a broken tibial nail with narrow canal. Eight different categories of implant removal methods were described, with different methods within each category. This classification is very comprehensive and was never described before. We described a new technique (hook captured in the medulla by flexible nail introduced from the locking hole which is a valuable technique in cases of nail of a small diameter where other methods cannot be used because of the narrow canal of the nail. Our eight categories for broken nail removal methods simplify the concepts of nail removal and allow the surgeon to better plan for the removal procedure.

  9. Wave motion in elastic solids

    CERN Document Server

    Graff, Karl F

    1991-01-01

    This highly useful textbook presents comprehensive intermediate-level coverage of nearly all major topics of elastic wave propagation in solids. The subjects range from the elementary theory of waves and vibrations in strings to the three-dimensional theory of waves in thick plates. The book is designed not only for a wide audience of engineering students, but also as a general reference for workers in vibrations and acoustics. Chapters 1-4 cover wave motion in the simple structural shapes, namely strings, longitudinal rod motion, beams and membranes, plates and (cylindrical) shells. Chapter

  10. Elastic Moduli of Carbon Nanohorns

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2011-01-01

    Full Text Available Carbon nanotube is a special case of carbon nanohorns or carbon nanocones with zero apex angle. Research into carbon nanohorns started almost at the same time as the discovery of nanotubes in 1991. Most researchers focused on the investigation of nanotubes, and the exploration of nanohorns attracted little attention. To model the carbon nanohorns, we make use of a more reliable second-generation reactive empirical bond-order potential by Brenner and coworkers. We investigate the elastic moduli and conclude that these nanohorns are equally strong and require in-depth investigation. The values of Young's and Shear moduli decrease with apex angle.

  11. Wave propagation in elastic solids

    CERN Document Server

    Achenbach, Jan

    1984-01-01

    The propagation of mechanical disturbances in solids is of interest in many branches of the physical scienses and engineering. This book aims to present an account of the theory of wave propagation in elastic solids. The material is arranged to present an exposition of the basic concepts of mechanical wave propagation within a one-dimensional setting and a discussion of formal aspects of elastodynamic theory in three dimensions, followed by chapters expounding on typical wave propagation phenomena, such as radiation, reflection, refraction, propagation in waveguides, and diffraction. The treat

  12. Industrial and residential electricity demand dynamics in Japan: How did price and income elasticities evolve from 1989 to 2014?

    International Nuclear Information System (INIS)

    Wang, Nan; Mogi, Gento

    2017-01-01

    This study estimates the price and income elasticities of industrial and residential electricity demand in Japan with the annual data from 1989 to 2014. A time varying parameter (TVP) model with the Kalman filter is applied to monitor the evolution of consumer behaviors in the “post-bubble” period given the exogenous shock (financial crisis in 2008) and the structural breaks (electricity deregulation and Fukushima Daiichi crisis). The TVP model can provide a robust estimation of elasticities and can detect the outliers and the structural breaks. The results suggest that both industrial and residential consumers become less sensitive to price after the electricity deregulation and the financial crisis, and more sensitive to price after the Fukushima Daiichi crisis. Especially the industrial sector is less sensitive to price after the retail deregulation. By contrast, the income elasticities of industrial and residential sector consumers are stable during the examined period. Results also indicate that a negative relationship exists between the price elasticity of electricity demand and the price level of electricity after the electric sector deregulation. Some insights on the further electric sector reform and the environmental taxation in Japan are also provided. - Highlights: • A time varying parameter model is calculated with the Kalman filter. • Income elasticities are stable while price elasticities are time-varying. • Industrial sector is less sensitive to price change than residential sector. • Negative relationship between price elasticity and price level is found.

  13. Supplementation with Eskimo Skin Care improves skin elasticity in women. A pilot study.

    Science.gov (United States)

    Segger, Dörte; Matthies, Andreas; Saldeen, Tom

    2008-01-01

    To investigate the question of whether supplementation with an oral oil formulation rich in natural stable fish oil can alter skin elasticity, transepidermal water loss (TEWL), and skin roughness in healthy women. Twenty-four healthy women aged 40-60 years participated in a single-blind randomized trial for testing the effect of a proprietary oral supplement for skin nutrition (Eskimo Skin Care) on skin elasticity, TEWL, and skin roughness. Skin elasticity was measured by an optical cutometer, TEWL by a water-loss module based upon the vapour gradient principle, and skin roughness with a three-dimensional microtopography imaging system. Skin elasticity increased by 10% after 3 months of treatment with the supplement, a statistically significant increase in comparison with the control group (p=0.0298). There was a trend, though not statistically significant, towards a positive influence on the skin's barrier function. No effect on the skin roughness was observed. Eskimo Skin Care, an oral preparation rich in natural stable fish oil, can improve skin elasticity.

  14. Surface elastic properties in silicon nanoparticles

    Science.gov (United States)

    Melis, Claudio; Giordano, Stefano; Colombo, Luciano

    2017-09-01

    The elastic behavior of the external surface of a solid body plays a key role in nanomechanical phenomena. While bulk elasticity enjoys the benefits of a robust theoretical understanding, many surface elasticity features remain unexplored: some of them are here addressed by blending together continuum elasticity and atomistic simulations. A suitable readdressing of the surface elasticity theory allows to write the balance equations in arbitrary curvilinear coordinates and to investigate the dependence of the surface elastic parameters on the mean and Gaussian curvatures of the surface. In particular, we predict the radial strain induced by surface effects in spherical and cylindrical silicon nanoparticles and provide evidence that the surface parameters are nearly independent of curvatures and, therefore, of the surface conformation.

  15. Elastic properties of spherically anisotropic piezoelectric composites

    International Nuclear Information System (INIS)

    En-Bo, Wei; Guo-Qing, Gu; Ying-Ming, Poon

    2010-01-01

    Effective elastic properties of spherically anisotropic piezoelectric composites, whose spherically anisotropic piezoelectric inclusions are embedded in an infinite non-piezoelectric matrix, are theoretically investigated. Analytical solutions for the elastic displacements and the electric potentials under a uniform external strain are derived exactly. Taking into account of the coupling effects of elasticity, permittivity and piezoelectricity, the formula is derived for estimating the effective elastic properties based on the average field theory in the dilute limit. An elastic response mechanism is revealed, in which the effective elastic properties increase as inclusion piezoelectric properties increase and inclusion dielectric properties decrease. Moreover, a piezoelectric response mechanism, of which the effective piezoelectric response vanishes due to the symmetry of spherically anisotropic composite, is also disclosed. (condensed matter: structure, thermal and mechanical properties)

  16. Effective elastic properties of damaged isotropic solids

    International Nuclear Information System (INIS)

    Lee, U Sik

    1998-01-01

    In continuum damage mechanics, damaged solids have been represented by the effective elastic stiffness into which local damage is smoothly smeared. Similarly, damaged solids may be represented in terms of effective elastic compliances. By virtue of the effective elastic compliance representation, it may become easier to derive the effective engineering constants of damaged solids from the effective elastic compliances, all in closed form. Thus, in this paper, by using a continuum modeling approach based on both the principle of strain energy equivalence and the equivalent elliptical micro-crack representation of local damage, the effective elastic compliance and effective engineering constants are derived in terms of the undamaged (virgin) elastic properties and a scalar damage variable for both damaged two-and three-dimensional isotropic solids

  17. Anomalous elasticity, fluctuations and disorder in elastic membranes

    Science.gov (United States)

    Le Doussal, Pierre; Radzihovsky, Leo

    2018-05-01

    Motivated by freely suspended graphene and polymerized membranes in soft and biological matter we present a detailed study of a tensionless elastic sheet in the presence of thermal fluctuations and quenched disorder. The manuscript is based on an extensive draft dating back to 1993, that was circulated privately. It presents the general theoretical framework and calculational details of numerous results, partial forms of which have been published in brief Letters (Le Doussal and Radzihovsky, 1992; 1993). The experimental realization atom-thin graphene sheets (Novoselov et al., 2004) have driven a resurgence in this fascinating subject, making our dated predictions and their detailed derivations timely. To this end we analyze the statistical mechanics of a generalized D-dimensional elastic "membrane" embedded in d dimensions using a self-consistent screening approximation (SCSA), that has proved to be unprecedentedly accurate in this system, exact in three complementary limits: (i) d → ∞, (ii) D → 4, and (iii) D = d. Focusing on the critical "flat" phase, for a homogeneous two-dimensional (D = 2) membrane embedded in three dimensions (d = 3), we predict its universal roughness exponent ζ = 0 . 590, length-scale dependent elastic moduli exponents η = 0 . 821 and ηu = 0 . 358, and an anomalous Poisson ratio, σ = - 1 / 3. In the presence of random uncorrelated heterogeneity the membrane exhibits a glassy wrinkled ground state, characterized by ζ‧ = 0 . 775 ,η‧ = 0 . 449, ηu‧ = 1 . 101 and a Poisson ratio σ‧ = - 1 / 3. Motivated by a number of physical realizations (charged impurities, disclinations and dislocations) we also study power-law correlated quenched disorder that leads to a variety of distinct glassy wrinkled phases. Finally, neglecting self-avoiding interaction we demonstrate that at high temperature a "phantom" sheet undergoes a continuous crumpling transition, characterized by a radius of gyration exponent, ν = 0 . 732 and η = 0

  18. Continuum mechanics elasticity, plasticity, viscoelasticity

    CERN Document Server

    Dill, Ellis H

    2006-01-01

    FUNDAMENTALS OF CONTINUUM MECHANICSMaterial ModelsClassical Space-TimeMaterial BodiesStrainRate of StrainCurvilinear Coordinate SystemsConservation of MassBalance of MomentumBalance of EnergyConstitutive EquationsThermodynamic DissipationObjectivity: Invariance for Rigid MotionsColeman-Mizel ModelFluid MechanicsProblems for Chapter 1BibliographyNONLINEAR ELASTICITYThermoelasticityMaterial SymmetriesIsotropic MaterialsIncompressible MaterialsConjugate Measures of Stress and StrainSome Symmetry GroupsRate Formulations for Elastic MaterialsEnergy PrinciplesGeometry of Small DeformationsLinear ElasticitySpecial Constitutive Models for Isotropic MaterialsMechanical Restrictions on the Constitutive RelationsProblems for Chapter 2BibliographyLINEAR ELASTICITYBasic EquationsPlane StrainPlane StressProperties of SolutionsPotential EnergySpecial Matrix NotationThe Finite Element Method of SolutionGeneral Equations for an Assembly of ElementsFinite Element Analysis for Large DeformationsProblems for Chapter 3Bibliograph...

  19. Pneumatic Variable Series Elastic Actuator.

    Science.gov (United States)

    Zheng, Hao; Wu, Molei; Shen, Xiangrong

    2016-08-01

    Inspired by human motor control theory, stiffness control is highly effective in manipulation and human-interactive tasks. The implementation of stiffness control in robotic systems, however, has largely been limited to closed-loop control, and suffers from multiple issues such as limited frequency range, potential instability, and lack of contribution to energy efficiency. Variable-stiffness actuator represents a better solution, but the current designs are complex, heavy, and bulky. The approach in this paper seeks to address these issues by using pneumatic actuator as a variable series elastic actuator (VSEA), leveraging the compressibility of the working fluid. In this work, a pneumatic actuator is modeled as an elastic element with controllable stiffness and equilibrium point, both of which are functions of air masses in the two chambers. As such, for the implementation of stiffness control in a robotic system, the desired stiffness/equilibrium point can be converted to the desired chamber air masses, and a predictive pressure control approach is developed to control the timing of valve switching to obtain the desired air mass while minimizing control action. Experimental results showed that the new approach in this paper requires less expensive hardware (on-off valve instead of proportional valve), causes less control action in implementation, and provides good control performance by leveraging the inherent dynamics of the actuator.

  20. Hummingbird tongues are elastic micropumps

    Science.gov (United States)

    Rico-Guevara, Alejandro; Fan, Tai-Hsi; Rubega, Margaret A.

    2015-01-01

    Pumping is a vital natural process, imitated by humans for thousands of years. We demonstrate that a hitherto undocumented mechanism of fluid transport pumps nectar onto the hummingbird tongue. Using high-speed cameras, we filmed the tongue–fluid interaction in 18 hummingbird species, from seven of the nine main hummingbird clades. During the offloading of the nectar inside the bill, hummingbirds compress their tongues upon extrusion; the compressed tongue remains flattened until it contacts the nectar. After contact with the nectar surface, the tongue reshapes filling entirely with nectar; we did not observe the formation of menisci required for the operation of capillarity during this process. We show that the tongue works as an elastic micropump; fluid at the tip is driven into the tongue's grooves by forces resulting from re-expansion of a collapsed section. This work falsifies the long-standing idea that capillarity is an important force filling hummingbird tongue grooves during nectar feeding. The expansive filling mechanism we report in this paper recruits elastic recovery properties of the groove walls to load nectar into the tongue an order of magnitude faster than capillarity could. Such fast filling allows hummingbirds to extract nectar at higher rates than predicted by capillarity-based foraging models, in agreement with their fast licking rates. PMID:26290074

  1. Elastic properties of graphite and interstitial defects

    International Nuclear Information System (INIS)

    Ayasse, J.-B.

    1977-01-01

    The graphite elastic constants C 33 and C 44 , reflecting the interaction of the graphitic planes, were experimentally measured as a function of irradiation and temperature. A model of non-central strength atomic interaction was established to explain the experimental results obtained. This model is valid at zero temperature. The temperature dependence of the elastic properties was analyzed. The influence of the elastic property variations on the specific heat of the lattice at very low temperature was investigated [fr

  2. Theory of stable allocations

    Directory of Open Access Journals (Sweden)

    Pantelić Svetlana

    2014-01-01

    Full Text Available The Swedish Royal Academy awarded the 2012 Nobel Prize in Economics to Lloyd Shapley and Alvin Roth, for the theory of stable allocations and the practice of market design. These two American researchers worked independently from each other, combining basic theory and empirical investigations. Through their experiments and practical design they generated a flourishing field of research and improved the performance of many markets. Born in 1923 in Cambridge, Massachusetts, Shapley defended his doctoral thesis at Princeton University in 1953. For many years he worked at RAND, and for more than thirty years he was a professor at UCLA University. He published numerous scientific papers, either by himself or in cooperation with other economists.

  3. Bi-stable optical actuator

    Science.gov (United States)

    Holdener, Fred R.; Boyd, Robert D.

    2000-01-01

    The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.

  4. Brazilian sawn wood price and income elasticity

    Directory of Open Access Journals (Sweden)

    Rommel Noce

    2010-09-01

    Full Text Available This study estimated the sawn wood demand price and income elasticity. Specifically it was estimated the priceelasticity of sawn wood, the cross price elasticity of wood panels and the income elasticity of Brazilian GDP. A log-log model withcorrection through outline of the mobile average (MA(1 was used, adjusted for the period of 1971 to 2006, which showed to bestable, with satisfactory significance levels. It was observed that sawn wood demand is inelastic in relation to price and elastic inrelation to income.

  5. Elastic properties of icosahedral and decagonal quasicrystals

    International Nuclear Information System (INIS)

    Chernikov, Mikhail A

    2005-01-01

    Problems associated with determining the symmetry properties of the elastic constant tensor of icosahedral and decagonal quasicrystals are reviewed. Notions of elastic isotropy and anisotropy are considered, and their relation to the components of the elastic constant tensor is discussed. The question is addressed of how to determine experimentally whether a system under study is elastically isotropic. Experimental results produced by resonant ultrasound spectroscopy of icosahedral Al-Li-Cu and decagonal Al-Ni-Co single quasicrystals are discussed in detail. (methodological notes)

  6. Faraday wave lattice as an elastic metamaterial.

    Science.gov (United States)

    Domino, L; Tarpin, M; Patinet, S; Eddi, A

    2016-05-01

    Metamaterials enable the emergence of novel physical properties due to the existence of an underlying subwavelength structure. Here, we use the Faraday instability to shape the fluid-air interface with a regular pattern. This pattern undergoes an oscillating secondary instability and exhibits spontaneous vibrations that are analogous to transverse elastic waves. By locally forcing these waves, we fully characterize their dispersion relation and show that a Faraday pattern presents an effective shear elasticity. We propose a physical mechanism combining surface tension with the Faraday structured interface that quantitatively predicts the elastic wave phase speed, revealing that the liquid interface behaves as an elastic metamaterial.

  7. Threshold anomaly in the elastic scattering of 6He on 209Bi

    International Nuclear Information System (INIS)

    Garcia, A. R.; Padron, I.; Lubian, J.; Gomes, P. R. S.; Lacerda, T.; Garcia, V. N.; Gomez-Camacho, A.; Aguilera, E. F.

    2009-01-01

    The energy dependence of the optical potential for the elastic scattering of 6 He on 209 Bi at near and subbarrier energies is studied. Elastic angular distributions and the reaction cross section were simultaneously fitted by performing some modifications in the ECIS code. A phenomenological optical model potential with the Woods-Saxon form was used. There are signatures that the so called breakup threshold anomaly (BTA) is present in this system having a halo projectile 6 He, as it had been found earlier for systems involving stable weakly bound nuclei. (Author)

  8. Elastic moduli and elastic anisotropy of cold sprayed metallic coatings

    Czech Academy of Sciences Publication Activity Database

    Seiner, Hanuš; Cizek, J.; Sedlák, Petr; Huang, R.; Cupera, J.; Dlouhý, I.; Landa, Michal

    2016-01-01

    Roč. 291, April (2016), s. 342-347 ISSN 0257-8972 R&D Projects: GA ČR GA13-13616S; GA ČR(CZ) GA13-35890S Grant - others:NETME Centre Plus - národní program udržitelnosti(CZ) LO1202 Institutional support: RVO:61388998 Keywords : kinetic spray * CGDS * elastic properties * metals and alloys * deposition * resonant ultrasound spectroscopy Subject RIV: JG - Metallurgy Impact factor: 2.589, year: 2016 http://ac.els-cdn.com/S0257897216301165/1-s2.0-S0257897216301165-main.pdf?_tid=1083617a-017f-11e6-92e7-00000aacb361&acdnat=1460555773_2e80d3df20843f3af649bf3ac71c8844

  9. COMPARATIVE STUDY BETWEEN TITANIUM ELASTIC NAILING (TENS AND DYNAMIC COMPRESSION PLATING (DCP IN THE TREATMENT OF FEMORAL DIAPHYSEAL FRACTURES IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Ramasubba Reddy

    2015-08-01

    Full Text Available BACKGROUND : Orthopaedic surgeons have long maintained that all children who have sustained a diaphyseal fracture of femur recover with c onservative treatment, given the excellent remodeling ability of immature bone in children. Angulations, shortenings and malrotations are not always corrected by conservative treatment. Of many surgical options, titanium elastic nailing has been the newer implant which is being used regularly. Although good results have been reported with elastic intramedullary nails, plate fixation continues to be a viable alternative in surgical treatment of femoral shaft fractures. However there are not many studies comp aring the efficiency of titanium elastic nailing and plating for femoral diaphyseal fractures in pediatric age group. AIM : The present study aims to compare the surgical management of diaphyseal fractures of femur in children with Dynamic Compression Plati ng versus Titanium Elastic Nailing. DESIGN : This is a prospective study . MATERIALS AND METHODS : This prospective study was conducted in a tertiary hospital. Patients who presented to the out - patient department and casualty of the hospital with femoral diap hyseal fractures during April 2012 to June 2014 were considered for the study. Subjects fulfilling the predetermined inclusion and exclusion criteria were included in the study. STATISTICAL METHODS : Fisher Exact test, Chi - Square Test, Student t test (Two t ailed, independent . RESULTS : Patients in the age group of 6 - 14 years were considered for the study, Patients were divided into two groups and treated with DCP/TENS. The duration of surgery, hospital stay, and, amount of blood loss was minimal in TENS grou p. Callus was seen early in TENS group. Radiological union was early in TENS group by 2 - 3 weeks. Outcome was better in patients treated with TENS (Excellent - 70%; Satisfactory – 30%; Poor - 0% in comparison to DCP (Excellent - 70%; Satisfactory - 25%; Poor - 5%. CO NCLUSION : TENS

  10. [Locked plating with minimally invasive percutaneous plate osteosynthesis versus intramedullary nailing of distal extra-articular tibial fracture: a retrospective study].

    Science.gov (United States)

    Yao, Qi; Ni, Jie; Peng, Li-bin; Yu, Da-xin; Yuan, Xiao-ming

    2013-12-17

    To compare the efficacies of minimally invasive plate osteosynthesis (MIPPO) and interlocking intramedullary nailing (IMN) in the treatment of extra-articular fractures of distal tibia. Retrospective reviews were conducted for 126 patients with extra-articular distal tibia fractures. Treatment was either MIPPO (n = 61) or IMN (n = 65). The outcomes were assessed by comparing operating duration, time to union, the last follow-up American Orthopedic Foot and Ankle Society (AOFAS) score and complication rate. The average follow-up period was 23.7 (12-53) months. In the minimally invasive plate osteosynthesis group, there were deep infections (n = 2), superficial infections (n = 5), delayed union (n = 2), malunion (n = 2) and knee joint pain (n = 10) were observed. In addition, the average operating duration (85.9 ± 18.9 min), average time to union (17.3 ± 3.8 weeks) and average AOFAS (83.2 ± 11.9) were analyzed. In the interlocking intramedullary nailing group, there were delayed union (n = 3), malunion (n = 12) and knee joint pain (n = 22). And the average operating duration (83.3 ± 15.7 min), average time to union (16.5 ± 3.1 weeks) and average AOFAS (84.9 ± 12.0) were analyzed. No statistical significance existed in operating duration, time to union and the last follow-up AOFAS between two groups (P > 0.05). However, the rates of malformation and knee joint pain were higher in the intramedullary nail group than those in the plate group. And the difference was statistically significant (P = 0.015, P = 0.025). Both MIPPO and IMN are effective for extra-articular fractures of distal tibia. However, the former has the advantage of lowers rate of malformation and knee joint pain. Therefore a surgeon should consider the degree of injury while managing extra-articular fracture of distal tibia.

  11. Percutaneous intramedullary decompression, curettage, and grafting with medical-grade calcium sulfate pellets for unicameral bone cysts in children: a new minimally invasive technique.

    Science.gov (United States)

    Dormans, John P; Sankar, Wudbhav N; Moroz, Leslie; Erol, Bülent

    2005-01-01

    Several treatment options exist for unicameral bone cysts (UBCs), including observation, steroid injection, bone marrow injection, and curettage and bone grafting. These are all associated with high recurrence rates, persistence, and occasional complications. Newer techniques have been described, most with variable success and only short follow-up reported. Because of these factors, a new minimally invasive percutaneous technique was developed for the treatment of UBCs in children. Twenty-eight children with UBCs who underwent percutaneous intramedullary decompression, curettage, and grafting with medical-grade calcium sulfate (MGCS) pellets by the senior author (J.P.D.) between April 2000 and April 2003 were analyzed as part of a pediatric musculoskeletal tumor registry at a large tertiary children's hospital. Four patients were lost to follow-up, and the remaining 24 patients had an average follow-up of 21.9 months (range 4-48 months). Twelve patients were followed for at least 24 months. Six of the 24 children had received previous treatment of their UBC, most often at an outside institution. Follow-up was performed through clinical evaluation and radiographic review. Postoperative radiographs at most recent follow-up showed complete healing, defined as more than 95% opacification, in 22 of 24 patients (91.7%). One patient (4.2%) demonstrated partial healing, defined as 80% to 95% opacification. One patient had less than 80% radiographic healing (4.2%). All 24 patients returned to full activities and were asymptomatic at most recent follow-up. The only complication noted was a superficial suture abscess that occurred in one patient; this resolved with local treatment measures. The new minimally invasive technique of percutaneous intramedullary decompression, curettage, and grafting with MGCS pellets demonstrates favorable results with low complication and recurrence rates compared with conventional techniques. The role of intramedullary decompression as a part

  12. Quasi-experimental taxation elasticities of US gasoline demand

    International Nuclear Information System (INIS)

    Goel, R.K.

    1994-01-01

    Taxation elasticities provide inputs in public policy aimed at raising revenues. Using the quasi-experimental method, this paper calculates gasoline taxation elasticities for the USA over 1952-86. The medium (mean) elasticity over this period is found to be -0.075 (-0.122). However, the elasticity following the oil shock of 1973 is found to be statistically different from the pre-shock elasticity. Reasons for this change in elasticity are discussed. The implication of this analysis is that tax policies based on price elasticities, rather than on tax elasticities, might be using an inappropriate elasticity estimate and consequently misinterpreting the government's ability to raise tax revenues. (author)

  13. Use of intra-medullary stacked nailing in the reduction of proximal plastic deformity in a pediatric Monteggia fracture: a case report

    Directory of Open Access Journals (Sweden)

    Huntley James S

    2011-04-01

    Full Text Available Abstract Introduction In a Monteggia fracture dislocation, it is important to reduce the ulnar fracture completely. Extensive plastic deformation of the proximal ulna may make reduction by closed manipulation impossible. Case presentation We report the case of a four-year-old Caucasian boy in whom the plastic deformation of the proximal ulna was reduced, and this reduction was maintained, using intra-medullary stacked nailing. Conclusion The technique of stacked nailing is a useful addition to the armamentarium in the management of the potentially awkward Monteggia fracture.

  14. Multidiscipline simulation of elastic manipulators

    Directory of Open Access Journals (Sweden)

    T. Rølvåg

    1992-10-01

    Full Text Available This paper contributes to multidiscipline simulation of elastic robot manipulators in FEDEM. All developments presented in this paper are based on the formulations in FEDEM, a simulation system developed by the authors which combines finite element, mechanism and control analysis. In order to establish this general simulation system as an efficient multidiscipline robot design tool a robot control system including a high level robot programming language, interpolation algorithms, path generation algorithms, forward and inverse kinematics, control systems, gear and transmission models are implemented. These new features provide a high level of integration between traditionally separate design disciplines from the very beginning of the design and optimization process. Several simulations have shown that high fidelity mathematical models can be derived and used as a basis for dynamic analysis and controller design in FEDEM.

  15. Wrinkling of Pressurized Elastic Shells

    KAUST Repository

    Vella, Dominic

    2011-10-01

    We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells are subject to a wrinkling instability. We study wrinkling in depth, presenting scaling laws for the critical indentation at which wrinkling occurs and the number of wrinkles formed in terms of the internal pressurization and material properties of the shell. These results are validated by numerical simulations. We show that the evolution of the wrinkle length with increasing indentation can be understood for highly pressurized shells from membrane theory. These results suggest that the position and number of wrinkles may be used in combination to give simple methods for the estimation of the mechanical properties of highly pressurized shells. © 2011 American Physical Society.

  16. Mathematical methods for elastic plates

    CERN Document Server

    Constanda, Christian

    2014-01-01

    Mathematical models of deformation of elastic plates are used by applied mathematicians and engineers in connection with a wide range of practical applications, from microchip production to the construction of skyscrapers and aircraft. This book employs two important analytic techniques to solve the fundamental boundary value problems for the theory of plates with transverse shear deformation, which offers a more complete picture of the physical process of bending than Kirchhoff’s classical one.   The first method transfers the ellipticity of the governing system to the boundary, leading to singular integral equations on the contour of the domain. These equations, established on the basis of the properties of suitable layer potentials, are then solved in spaces of smooth (Hölder continuous and Hölder continuously differentiable) functions.   The second technique rewrites the differential system in terms of complex variables and fully integrates it, expressing the solution as a combination of complex ana...

  17. The visco-elastic multilayer program VEROAD

    NARCIS (Netherlands)

    Hopman, P.C.

    1996-01-01

    The mathematical principles and derivation of a linear visco-elastic multilayer computer program are described. The mathematical derivation is based on Fourier Transformation. The program is called VEROAD, which is an acronym for Visco-Elastic ROad Analysis Delft. The program allows calculation of

  18. Heavy ion elastic scattering of code : OPTHI

    International Nuclear Information System (INIS)

    Ismail, M.; Divatia, A.S.

    1982-01-01

    A computer code, OPTHI has been designed to calculate nuclear optical model elastic cross sections for the scattering of heavy ions. The program has been designed to be utilitarian rather than capable of giving an exact description of elastic scattering. Input format is described and the program listing is given. (M.G.B.)

  19. Thermo-elastic optical coherence tomography

    NARCIS (Netherlands)

    Wang, Tianshi; Pfeiffer, Tom; Wu, Min; Wieser, Wolfgang; Amenta, Gaetano; Draxinger, Wolfgang; van der Steen, A.F.W.; Huber, Robert; Van Soest, Gijs

    2017-01-01

    The absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue. A sub-micrometer scale displacement occurs within a few microseconds after the pulse arrival. In this Letter, we investigate the laser-induced thermo-elastic deformation using a 1.5 MHz phase-sensitive

  20. Dynamic elasticity measurement for prosthetic socket design.

    Science.gov (United States)

    Kim, Yujin; Kim, Junghoon; Son, Hyeryon; Choi, Youngjin

    2017-07-01

    The paper proposes a novel apparatus to measure the dynamic elasticity of human limb in order to help the design and fabrication of the personalized prosthetic socket. To take measurements of the dynamic elasticity, the desired force generated as an exponential chirp signal in which the frequency increases and amplitude is maintained according to time progress is applied to human limb and then the skin deformation is recorded, ultimately, to obtain the frequency response of its elasticity. It is referred to as a Dynamic Elasticity Measurement Apparatus (DEMA) in the paper. It has three core components such as linear motor to provide the desired force, loadcell to implement the force feedback control, and potentiometer to record the skin deformation. After measuring the force/deformation and calculating the dynamic elasticity of the limb, it is visualized as 3D color map model of the limb so that the entire dynamic elasticity can be shown at a glance according to the locations and frequencies. For the visualization, the dynamic elasticities measured at specific locations and frequencies are embodied using the color map into 3D limb model acquired by using 3D scanner. To demonstrate the effectiveness, the visualized dynamic elasticities are suggested as outcome of the proposed system, although we do not have any opportunity to apply the proposed system to the amputees. Ultimately, it is expected that the proposed system can be utilized to design and fabricate the personalized prosthetic socket in order for releasing the wearing pain caused by the conventional prosthetic socket.

  1. 7 CFR 29.2515 - Elasticity.

    Science.gov (United States)

    2010-01-01

    ...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2515 Elasticity. The flexible, springy... 7 Agriculture 2 2010-01-01 2010-01-01 false Elasticity. 29.2515 Section 29.2515 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...

  2. 7 CFR 29.3516 - Elasticity.

    Science.gov (United States)

    2010-01-01

    ... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3516 Elasticity. The flexible, springy nature of the tobacco leaf to recover... 7 Agriculture 2 2010-01-01 2010-01-01 false Elasticity. 29.3516 Section 29.3516 Agriculture...

  3. 7 CFR 29.1014 - Elasticity.

    Science.gov (United States)

    2010-01-01

    ... INSPECTION Standards Official Standard Grades for Flue-Cured Tobacco (u.s. Types 11, 12, 13, 14 and Foreign Type 92) § 29.1014 Elasticity. The flexible, springy nature of the tobacco leaf to recover... 7 Agriculture 2 2010-01-01 2010-01-01 false Elasticity. 29.1014 Section 29.1014 Agriculture...

  4. 7 CFR 29.2265 - Elasticity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Elasticity. 29.2265 Section 29.2265 Agriculture... INSPECTION Standards Official Standard Grades for Virginia Fire-Cured Tobacco (u.s. Type 21) § 29.2265 Elasticity. The flexible, springy nature of the tobacco leaf to recover approximately its original size and...

  5. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2017-03-08

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  6. Modelling the elastic properties of cellulose nanopaper

    DEFF Research Database (Denmark)

    Mao, Rui; Goutianos, Stergios; Tu, Wei

    2017-01-01

    The elastic modulus of cellulose nanopaper was predicted using a two-dimensional (2D) micromechanical fibrous network model. The elastic modulus predicted by the network model was 12 GPa, which is well within the range of experimental data for cellulose nanopapers. The stress state in the network...

  7. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2017-01-01

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  8. Intramedullary nail versus dynamic compression plate fixation in treating humeral shaft fractures: grading the evidence through a meta-analysis.

    Directory of Open Access Journals (Sweden)

    JianXiong Ma

    Full Text Available There is a debate regarding the choice of operative intervention in humeral shaft fractures that require surgical intervention. The choices for operative interventions include intramedullary nailing (IMN and dynamic compression plate (DCP. This meta-analysis was performed to compare fracture union, functional outcomes, and complication rates in patients treated with IMN or DCP for humeral shaft fractures and to develop GRADE (Grading of Recommendations, Assessment, Development, and Evaluation-based recommendations for using the procedures to treat humeral shaft fractures. A systematic search of all the studies published through December 2012 was conducted using the Medline, Embase, Sciencedirect, OVID and Cochrane Central databases. The randomized controlled trials (RCTs and quasi-RCTs that compared IMN with DCP in treating adult patients with humeral shaft fractures and provided data regarding the safety and clinical effects were identified. The demographic characteristics, adverse events and clinical outcomes were manually extracted from all of the selected studies. Ten studies that included a total of 448 patients met the inclusion criteria. The results of a meta-analysis indicated that both IMN and DCP can achieve similar fracture union with a similar incidence of radial nerve injury and infection. IMN was associated with an increased risk of shoulder impingement, more restriction of shoulder movement, an increased risk of intraoperative fracture comminution, a higher incidence of implant failure, and an increased risk of re-operation. The overall GRADE system evidence quality was very low, which reduces our confidence in the recommendations of this system. DCP may be superior to IMN in the treatment of humeral shaft fractures. Because of the low quality evidence currently available, high-quality RCTs are required.

  9. Biomechanical assessment of composite versus metallic intramedullary nailing system in femoral shaft fractures: A finite element study.

    Science.gov (United States)

    Samiezadeh, Saeid; Tavakkoli Avval, Pouria; Fawaz, Zouheir; Bougherara, Habiba

    2014-08-01

    Intramedullary nails are the primary choice for treating long bone fractures. However, complications following nail surgery including non-union, delayed union, and fracture of the bone or the implant still exist. Reducing nail stiffness while still maintaining sufficient stability seems to be the ideal solution to overcome the abovementioned complications. In this study, a new hybrid concept for nails made of carbon fibers/flax/epoxy was developed in order to reduce stress shielding. The mechanical performance of this new implant in terms of fracture stability and load sharing was assessed using a comprehensive non-linear FE model. This model considers several mechanical factors in nine fracture configurations at immediately post-operative, and in the healed bone stages. Post-operative results showed that the hybrid composite nail increases the average normal force at the fracture site by 319.23N (P<0.05), and the mean stress in the vicinity of fracture by 2.11MPa (P<0.05) at 45% gait cycle, while only 0.33mm and 0.39mm (P<0.05) increases in the fracture opening and the fragments' shear movement were observed. The healed bone results revealed that implantation of the titanium nail caused 20.2% reduction in bone stiffness, while the composite nail lowered the stiffness by 11.8% as compared to an intact femur. Our results suggest that the composite nail can provide a preferred mechanical environment for healing, particularly in transverse shaft fractures. This may help bioengineers better understand the biomechanics of fracture healing, and aid in the design of effective implants. Copyright © 2014. Published by Elsevier Ltd.

  10. Safety of intramedullary autologous peripheral nerve grafts for post-rehabilitated complete motor spinal cord injuries: a phase I study.

    Directory of Open Access Journals (Sweden)

    Nazi Derakhshanrad

    2013-12-01

    Full Text Available Many experimental studies have reported behavioral improvement after transplantation of peripheral nerve tissue into the contused spinal cord, even in large animals. The safety of this treatment in human remains unknown. In this translational phase 1 study, safety of peripheral nerve grafting for chronic spinal cord injuries and possible outcomes are being reported. Twelve complete motor spinal cord injury patients, who had finished their rehabilitation program, were enrolled. There were 4 thoracic and 8 cervical cases. Patients underwent sural nerve preconditioning in the calf, followed 1 week later, by intramedullary transplantation of the harvested nerve fascicles. The patients were followed up for potential complications periodically, and final assessment by American Spinal Injury association (ASIA and Spinal Cord Independence Measure (SCIM III were reported after 2 years of follow-up. The median duration of the spinal cord injury was 31 months. At two years of follow up, out of 7 cases with ASIA Impairment Scale (AIS A, 4(57.1% cases improved to AIS B and 1 (14.3% case became AIS C. There were 1 patient with transient increased spasm, one case of transient cystitis, 3 patients with transient increased neuropathic pain and 1 case with transient episode of autonomic dysreflexia, all being managed medically. There was no case of donor site infection. The above complications were transient as they responded to temporary medical treatment. It may be deduced that after two years follow-up of patients that the procedure may be safe, however further controlled studies are needed to prove its efficacy.

  11. Cervical myelopathy due to single level disc herniation presenting as intramedullary mass lesion: What to do first?

    Directory of Open Access Journals (Sweden)

    Murat Sakir Eksi

    2015-01-01

    Full Text Available Cervical myelopathy (CM is mostly a degenerative process ending in myelopathic and/or radiculopathic syndromes. On T2-weighted magnetic resonance imaging (MRI, CM appears as a hyperintense area near the spondylotic spine. This high intensity signal depends on the impact of outer forces and their duration. It also determines the prognosis of the surgical candidate. A 40-year-old male patient admitted to our clinic with right upper extremity weakness and hypoesthesia that had started 2 months earlier. On neurological examination there was 2/5 motor weakness of right biceps brachii, and hypoesthesia over right C6 dermatome. Right upper extremity deep tendon reflexes were hypoactive, but lower ones were hyperactive. After clinical and radiological work-up, preliminary diagnosis was directed to a spinal intramedullary tumor. Total resection of the herniated cervical disc fragment and the mass lesion was managed. Pathology of the mass lesion was compatible with subacute infarct tissue and inflammatory response. Final diagnosis was CM under effect of cervical disc herniation. Contrast-enhanced spinal cord myelopathic lesions are very rare and resemble much more tumors and inflammatory processes. However, the principal treatment approach totally differs depending on pathology. When there are both a disc herniation and a high clinical suspicion; biopsy should be delayed. The most probable solution will be surgery for the disc disease with thorough preoperative scanning of vascular malformations; clinical and radiological close follow-up after surgery. Biopsy or surgical resection can be performed if patient deteriorates despite the primary surgery.

  12. Forest biomass and Armington elasticities in Europe

    International Nuclear Information System (INIS)

    Lundmark, Robert; Shahrammehr, Shima

    2011-01-01

    The purpose of this paper is to provide estimated Armington elasticities for selected European countries and for three forest biomass commodities of main interest in many energy models: roundwood, chips and particles and wood residues. The Armington elasticity is based on the assumption that a specific forest biomass commodity is differentiated by its origin. The statistically significant estimated Armington elasticities range from 0.52 for roundwood in Hungary to approximately 4.53 for roundwood in Estonia. On average, the statistically significant Armington elasticity for chips and particles over all countries is 1.7 and for wood residues and roundwood 1.3 and 1.5, respectively. These elasticities can provide benchmark values for simulation models trying to assess trade patterns of forest biomass commodities and energy policy effects for European countries or for the EU as a whole.

  13. Elasticity of Substitution and Antidumping Measures

    DEFF Research Database (Denmark)

    Drud Hansen, Jørgen; Meinen, Philipp; Nielsen, Jørgen Ulff-Møller

    Abstract This paper analyzes the role of the elasticity of substitution for anti-dumping decisions across countries. In monopolistic competition models with cost heterogeneous firms across countries, price differences vary inversely with the elasticity of substitution. Anti-dumping duties should...... therefore also vary inversely with the elasticity of substitution at least for countries which have a strong focus on prices in the determination of their anti-dumping measures. We test this for ten countries from 1990 to 2009 using data on anti-dumping from Chad Bown (2010) and US-data at 8-digit level...... in our empirical investigation support the predicted role of the elasticity of substitution as we find a significant negative relation between the elasticity of substitution and the final anti-dumping duties for the ‘lesser duty rule’ group of countries. The countries which do not follow the ‘lesser duty...

  14. Calculation of elastic-plastic strain ranges for fatigue analysis based on linear elastic stresses

    International Nuclear Information System (INIS)

    Sauer, G.

    1998-01-01

    Fatigue analysis requires that the maximum strain ranges be known. These strain ranges are generally computed from linear elastic analysis. The elastic strain ranges are enhanced by a factor K e to obtain the total elastic-plastic strain range. The reliability of the fatigue analysis depends on the quality of this factor. Formulae for calculating the K e factor are proposed. A beam is introduced as a computational model for determining the elastic-plastic strains. The beam is loaded by the elastic stresses of the real structure. The elastic-plastic strains of the beam are compared with the beam's elastic strains. This comparison furnishes explicit expressions for the K e factor. The K e factor is tested by means of seven examples. (orig.)

  15. Electronic structure, elasticity, bonding features and mechanical behaviour of zinc intermetallics: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Fatima, Bushra, E-mail: bushrafatima25@gmail.com; Acharya, Nikita; Sanyal, Sankar P. [Department of Physics, Barkatullah University, Bhopal, 462026 (India)

    2016-05-06

    The structural stability, electronic structure, elastic and mechanical properties of TiZn and ZrZn intermetallics have been studied using ab-initio full potential linearized augmented plane wave (FP-LAPW) method within generalized gradient approximation for exchange and correlation potentials. The various structural parameters, such as lattice constant (a{sub 0}), bulk modulus (B), and its pressure derivative (B’) are analysed and compared. The investigation of elastic constants affirm that both TiZn and ZrZn are elastically stable in CsCl (B{sub 2} phase) structure. The electronic structures have been analysed quantitatively from the band structure which reveals the metallic nature of these compounds. To better illustrate the nature of bonding and charge transfer, we have also studied the Fermi surfaces. The three well known criterion of ductility namely Pugh’s rule, Cauchy’s pressure and Frantsevich rule elucidate the ductile nature of these compounds.

  16. Elastic and thermal properties of silicon compounds from first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Haijun; Zhu, H.J. [Yancheng Institute of Technology (China). School of Materials Engineering; Cheng, W.H. [Yancheng Institute of Technology (China). Dept. of Light Chemical Engineering; Xie, L.H. [Sichuan Normal Univ., Chengdu (China). Inst. of Solid State Physics and School of Physics and Electronic Engineering

    2016-11-01

    The structural and elastic properties of V-Si (V{sub 3}Si, VSi{sub 2}, V{sub 5}Si{sub 3}, and V{sub 6}Si{sub 5}) compounds are studied by using first-principles method. The calculated equilibrium lattice parameters and formation enthalpy are in good agreement with the available experimental data and other theoretical results. The calculated results indicate that the V-Si compounds are mechanically stable. Elastic properties including bulk modulus, shear modulus, Young's modulus, and Poisson's ratio are also obtained. The elastic anisotropies of V-Si compounds are investigated via the three-dimensional (3D) figures of directional dependences of reciprocals of Young's modulus. Finally, based on the quasi-harmonic Debye model, the internal energy, Helmholtz free energy, entropy, heat capacity, thermal expansion coefficient, Grueneisen parameter, and Debye temperature of V-Si compounds have been calculated.

  17. Shape Recovery of Elastic Red Blood Cells from Shear Flow Induced Deformation in Three Dimensions

    Science.gov (United States)

    Peng, Yan; Gounley, John

    2015-11-01

    Red blood cells undergo substantial shape changes in vivo. Modeled as an elastic capsule, the shape recovery of a three dimensional biconcave capsule from shear flow is studied for different preferred elastic and bending configuration. The fluid-structure interaction is modeled using the multiple-relaxation time lattice Boltzmann (LBM) and immersed boundary (IBM) methods. Based on the studies of the limited shape memory observed in three dimensions, the shape recovery is caused by the preferred elastic configuration, at least when paired with a constant spontaneous curvature. For these capsules, the incompleteness of the shape recovery observed precludes any conjecture about whether a single or multiple phase(s) are necessary to describe the recovery process. Longer simulations and a more stable methodology will be necessary. Y. Peng acknowledges support from Old Dominion University Research Foundation Grant #503921 and National Science Foundation Grant DMS-1319078.

  18. [Tibio-talo-calcaneal arthrodesis with the retrograde intramedullary nail MEDIN].

    Science.gov (United States)

    Popelka, S; Vavřík, P; Landor, I; Bek, J; Popelka ml, S; Hromádka, R

    2013-01-01

    .3%) patients (two had RA). The infection was managed by revision surgery with nail removal and irrigation. All patients healed well. Necrosis of the talus and development of a pseudoarthrosis were recorded in four (6.4%) patients, who subsequently underwent nail removal and repeat fusion using an external fixator. Retrograde nailing for tibio-talo-calcaneal arthrodesis is used by many authors. Its complication rate is comparable with the other methods of arthrodesis. The use of tibio-talo-calcaneal arthrodesis aims at a painless and stable joint. Arthrodesis of the talus and the subtalar joint using a retrograde nail is an effective surgical treatment of the joints affected. It is especially recommended for RA patients who have severe deviations. Retrograde nailing provides a stable osteosynthesis which does not require plaster cast immobilisation. The double-curved nail allows for its insertion in the solid part of the calcaneus and helps avoiding injury to the neurovascular bundle.

  19. New empirical generalizations on the determinants of price elasticity

    NARCIS (Netherlands)

    Bijmolt, THA; Van Heerde, HJ; Pieters, RGM

    The importance of pricing decisions for firms has fueled an extensive stream of research on price elasticities. In an influential meta-analytical study, Tellis (1988) summarized price elasticity research findings until 1986. However, empirical generalizations on price elasticity require

  20. One-dimensional stable distributions

    CERN Document Server

    Zolotarev, V M

    1986-01-01

    This is the first book specifically devoted to a systematic exposition of the essential facts known about the properties of stable distributions. In addition to its main focus on the analytic properties of stable laws, the book also includes examples of the occurrence of stable distributions in applied problems and a chapter on the problem of statistical estimation of the parameters determining stable laws. A valuable feature of the book is the author's use of several formally different ways of expressing characteristic functions corresponding to these laws.

  1. Stable and unstable crack growth in Type 304 stainless steel plate

    International Nuclear Information System (INIS)

    Yagawa, G.

    1984-01-01

    Experimental and theoretical results on stable as well as unstable fractures for Type 304 stainless steel plates with a central crack subjected to tension force are given. In the experiment using a testing machine with a special spring for high compliance, the transition points from the stable to the unstable crack growth are observed and comparisons are made between the test results and the finite element solutions. A round robin calculation for the elastic-plastic stable crack growth using one of the specimens mentioned above is also given. (orig.)

  2. Minimizing Leg Length Discrepancy After Intramedullary Nailing of Comminuted Femoral Shaft Fractures: A Quality Improvement Initiative Using the Scout Computed Tomography Scanogram.

    Science.gov (United States)

    Gheraibeh, Petra; Vaidya, Rahul; Hudson, Ian; Meehan, Robert; Tonnos, Frederick; Sethi, Anil

    2018-05-01

    To prevent leg length discrepancy (LLD) after locked femoral nailing in patients with comminuted femoral shaft fractures. Prospective consecutive case series aimed at quality improvement. Level 1 Trauma Center PATIENTS:: Ninety-eight consecutive patients with a comminuted femoral shaft fracture underwent statically locked intramedullary nailing, with a focused attempt at minimizing LLD during surgery. A computed tomography scanogram of both legs was performed on postoperative day 1 to assess for residual LLD. Patients were offered the option to have LLD >1.5 cm corrected before discharge. LLD >1.5 cm. Twenty-one patients (21.4%) were found to have an LLD >1.5 cm. An LLD >1.5 cm occurred in 10/55 (18%) antegrade nail patients and 11/43 (26%) retrograde nail patients (P = 0.27). No difference was noted based on the mechanism of injury, surgeon training and OTA/AO type B versus C injury. Ninety of 98 patients left with 1.5 cm after locked intramedullary nailing for a comminuted femoral shaft fracture without being informed and the option of early correction. We recommend using a full-length computed tomography scanogram after IM nailing of comminuted femur fractures to prevent iatrogenic LLD. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  3. Use of the suprapatellar approach in intramedullary nailing of a multi-fragmentary dislocated tibia fracture with a hypermobile intermediate fragment in a young patient

    Directory of Open Access Journals (Sweden)

    Patrick Haubruck

    2017-01-01

    Full Text Available A case of an adolescent female patient who suffered from first grade open multi-fragment fracture of the tibia (AO42-C2 with a large hypermobile intermediate fragment is presented in this case report. Intramedullary nailing of the tibia remains the treatment of choice despite a high risk of malformation and anterior knee pain especially in multi-fragment fractures. Here the suprapatellar approach as a semiextended nailing technique seems favorable. The specialty in our case was an early change of procedures necessary due to persistent swelling during external fixation based on the hypermobile intermediate fragment. Decision in favor of this surgical technique was conducted in order to achieve beneficial alignment and union while protecting the softtissue despite the hypermobile intermediate fragment and decrease the risk of anterior knee pain. In our case we achieved successful alignment and proper bone healing without any signs of anterior knee pain or limitations in the range of motion of the knee. With this report we would like to recommend the suprapatellar approach as a favorable alternative in intramedullary nailing in this type of fracture also in young patients.

  4. Elastic metamaterial beam with remotely tunable stiffness

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Wei [University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Yu, Zhengyue [School of Naval Architecture, Ocean & Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Xiaole [School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Lai, Yun [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Yellen, Benjamin B., E-mail: yellen@duke.edu [University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Mechanical Engineering and Materials Science, Duke University, P.O. Box 90300, Hudson Hall, Durham, North Carolina 27708 (United States)

    2016-02-07

    We demonstrate a dynamically tunable elastic metamaterial, which employs remote magnetic force to adjust its vibration absorption properties. The 1D metamaterial is constructed from a flat aluminum beam milled with a linear array of cylindrical holes. The beam is backed by a thin elastic membrane, on which thin disk-shaped permanent magnets are mounted. When excited by a shaker, the beam motion is tracked by a Laser Doppler Vibrometer, which conducts point by point scanning of the vibrating element. Elastic waves are unable to propagate through the beam when the driving frequency excites the first elastic bending mode in the unit cell. At these frequencies, the effective mass density of the unit cell becomes negative, which induces an exponentially decaying evanescent wave. Due to the non-linear elastic properties of the membrane, the effective stiffness of the unit cell can be tuned with an external magnetic force from nearby solenoids. Measurements of the linear and cubic static stiffness terms of the membrane are in excellent agreement with experimental measurements of the bandgap shift as a function of the applied force. In this implementation, bandgap shifts by as much as 40% can be achieved with ∼30 mN of applied magnetic force. This structure has potential for extension in 2D and 3D, providing a general approach for building dynamically tunable elastic metamaterials for applications in lensing and guiding elastic waves.

  5. Microstructural evolution in inhomogeneous elastic media

    International Nuclear Information System (INIS)

    Jou, H.J.; Leo, P.H.; Lowengrub, J.S.

    1997-01-01

    We simulate the diffusional evolution of microstructures produced by solid state diffusional transformations in elastically stressed binary alloys in two dimensions. The microstructure consists of arbitrarily shaped precipitates embedded coherently in an infinite matrix. The precipitate and matrix are taken to be elastically isotropic, although they may have different elastic constants (elastically inhomogeneous). Both far-field applied strains and mismatch strains between the phases are considered. The diffusion and elastic fields are calculated using the boundary integral method, together with a small scale preconditioner to remove ill-conditioning. The precipitate-matrix interfaces are tracked using a nonstiff time updating method. The numerical method is spectrally accurate and efficient. Simulations of a single precipitate indicate that precipitate shapes depend strongly on the mass flux into the system as well as on the elastic fields. Growing shapes (positive mass flux) are dendritic while equilibrium shapes (zero mass flux) are squarish. Simulations of multiparticle systems show complicated interactions between precipitate morphology and the overall development of microstructure (i.e., precipitate alignment, translation, merging, and coarsening). In both single and multiple particle simulations, the details of the microstructural evolution depend strongly o the elastic inhomogeneity, misfit strain, and applied fields. 57 refs., 24 figs

  6. Elastic metamaterial beam with remotely tunable stiffness

    Science.gov (United States)

    Qian, Wei; Yu, Zhengyue; Wang, Xiaole; Lai, Yun; Yellen, Benjamin B.

    2016-02-01

    We demonstrate a dynamically tunable elastic metamaterial, which employs remote magnetic force to adjust its vibration absorption properties. The 1D metamaterial is constructed from a flat aluminum beam milled with a linear array of cylindrical holes. The beam is backed by a thin elastic membrane, on which thin disk-shaped permanent magnets are mounted. When excited by a shaker, the beam motion is tracked by a Laser Doppler Vibrometer, which conducts point by point scanning of the vibrating element. Elastic waves are unable to propagate through the beam when the driving frequency excites the first elastic bending mode in the unit cell. At these frequencies, the effective mass density of the unit cell becomes negative, which induces an exponentially decaying evanescent wave. Due to the non-linear elastic properties of the membrane, the effective stiffness of the unit cell can be tuned with an external magnetic force from nearby solenoids. Measurements of the linear and cubic static stiffness terms of the membrane are in excellent agreement with experimental measurements of the bandgap shift as a function of the applied force. In this implementation, bandgap shifts by as much as 40% can be achieved with ˜30 mN of applied magnetic force. This structure has potential for extension in 2D and 3D, providing a general approach for building dynamically tunable elastic metamaterials for applications in lensing and guiding elastic waves.

  7. Elastic Stability of Concentric Tube Robots: A Stability Measure and Design Test.

    Science.gov (United States)

    Gilbert, Hunter B; Hendrick, Richard J; Webster, Robert J

    2016-02-01

    Concentric tube robots are needle-sized manipulators which have been investigated for use in minimally invasive surgeries. It was noted early in the development of these devices that elastic energy storage can lead to rapid snapping motion for designs with moderate to high tube curvatures. Substantial progress has recently been made in the concentric tube robot community in designing snap-free robots, planning stable paths, and characterizing conditions that result in snapping for specific classes of concentric tube robots. However, a general measure for how stable a given robot configuration is has yet to be proposed. In this paper, we use bifurcation and elastic stability theory to provide such a measure, as well as to produce a test for determining whether a given design is snap-free (i.e. whether snapping can occur anywhere in the unloaded robot's workspace). These results are useful in designing, planning motions for, and controlling concentric tube robots with high curvatures.

  8. A comparative study of the therapeutic effect between long and short intramedullary nails in the treatment of intertrochanteric femur fractures in the elderly.

    Science.gov (United States)

    Guo, Xue-Feng; Zhang, Ke-Ming; Fu, Hong-Bo; Cao, Wen; Dong, Qiang

    2015-01-01

    To compare the clinical effects of long vs. short intramedullary nails in the treatment of intertrochanteric fractures in old patients more than 65 years old. A retrospective analysis of 178 cases of intertrochanteric fractures of the femur (AO type A1 and A2) in the elderly was conducted from January 2008 to December 2013. There were 85 males (47.8%) and 93 females (52.2%) with the age of 65e89 (70.2±10.8) years. The patients were treated by closed reduction and long or short intramedullary nail (Gamma 3) fixation. The length of short nail was 180 mm and that for long nail was 320e360 mm. The general data of patients, operation time, intraoperative blood loss, length of hospital stay, preoperative hemoglobin level, blood transfusion rate, postoperative periprosthetic fractures, infections, complications, etc were carefully recorded. There were 76 cases (42.7%) in the long intramedullary nail group and 102 cases (57.3%) in the short nail group. All the cases were followed up for 12e48 (21.3±6.8) months, during which there were 21 deaths (11.8%), mean (13.8±6.9) months after operation. The intraoperative blood loss was (90.7±50.6) ml in short nail group, greatly less than that in long nail group (127.8±85.9) ml (p=0.004). The short nail group also had a significantly shorter operation time (43.5 min±12.3 min vs. 58.5 min±20.3 min, p=0.002) and lower rate of postoperative transfusion (42.3% vs. 56.7%, p=0.041). But the length of hospital stay showed no big differences. After operation, in each group there was 1 case of periprosthetic fracture with a total incidence of 1.1%, 1.3% in long nail group and 0.9% in short nail group. At the end of the follow-up, all patients achieved bony union. The average healing time of the long nail group was (6.5±3.1) months, and the short nail group was (6.8±3.7) months, revealing no significant differences (p=0.09). Postoperative complications showed no great differences either. Both the intramedullary long and short nail

  9. Elastic/Inelastic Measurement Project

    International Nuclear Information System (INIS)

    Yates, Steven; Hicks, Sally; Vanhoy, Jeffrey; McEllistrem, Marcus

    2015-12-01

    The work scope involves the measurement of neutron scattering from natural sodium ( 23 Na) and two isotopes of iron, 56 Fe and 54 Fe. Angular distributions, i.e., differential cross sections, of the scattered neutrons will be measured for 5 to 10 incident neutron energies per year. The work of the first year concentrates on 23 Na, while the enriched iron samples are procured. Differential neutron scattering cross sections provide information to guide nuclear reaction model calculations in the low-@@energy (few MeV) fast-@@neutron region. This region lies just above the isolated resonance region, which in general is well studied; however, model calculations are difficult in this region because overlapping resonance structure is evident and direct nuclear reactions are becoming important. The standard optical model treatment exhibits good predictive ability for the wide-@@region average cross sections but cannot treat the overlapping resonance features. In addition, models that do predict the direct reaction component must be guided by measurements to describe correctly the strength of the direct component, e.g., @@ 2 must be known to describe the direct component of the scattering to the first excited state. Measurements of the elastic scattering differential cross sections guide the optical model calculations, while inelastic differential cross sections provide the crucial information for correctly describing the direct component. Activities occurring during the performance period are described.

  10. Elastic/Inelastic Measurement Project

    Energy Technology Data Exchange (ETDEWEB)

    Yates, Steven [Univ. of Kentucky, Lexington, KY (United States); Hicks, Sally [Univ. of Dallas, TX (United States); Vanhoy, Jeffrey [U.S. Naval Academy, Annapolis, MD (United States); McEllistrem, Marcus [Univ. of Kentucky, Lexington, KY (United States)

    2016-03-01

    The work scope involves the measurement of neutron scattering from natural sodium (23Na) and two isotopes of iron, 56Fe and 54Fe. Angular distributions, i.e., differential cross sections, of the scattered neutrons will be measured for 5 to 10 incident neutron energies per year. The work of the first year concentrates on 23Na, while the enriched iron samples are procured. Differential neutron scattering cross sections provide information to guide nuclear reaction model calculations in the low-­energy (few MeV) fast-­neutron region. This region lies just above the isolated resonance region, which in general is well studied; however, model calculations are difficult in this region because overlapping resonance structure is evident and direct nuclear reactions are becoming important. The standard optical model treatment exhibits good predictive ability for the wide-­region average cross sections but cannot treat the overlapping resonance features. In addition, models that do predict the direct reaction component must be guided by measurements to describe correctly the strength of the direct component, e.g., β2 must be known to describe the direct component of the scattering to the first excited state. Measurements of the elastic scattering differential cross sections guide the optical model calculations, while inelastic differential cross sections provide the crucial information for correctly describing the direct component. Activities occurring during the performance period are described.

  11. SIMULATION OFTHERMO-ELASTICS PROPERTIESOFTHERMALBARRIERCOATINGS

    Directory of Open Access Journals (Sweden)

    A.M.Ferouani M. Ferouani

    2015-07-01

    Full Text Available Thermal barrier coatings are used to protect different parts in compressors and turbines from heat. They are generally composed of two layers, one metallic layer providing resistance to heat corrosion and oxidation, and one thermally insulating ceramic layer. Two different techniques are industrially used. Plasma spray results in a lamellar structure granting a low thermal conductivity, but with a low thermal expansion compliance. Electron Beam Physical Vapour Deposition generates a columnar structure allowing a better accommodation of the thermal expansion stresses, entailing improved lifetime of the coating, but with a higher thermal conductivity. The aim of the paper presented here is to develop a procedure of analysis based on the micro structural observation for the prediction of the properties of new coatings in court of industrial development and to predict the effect of the posterior thermal treatment on the properties of the coatings carried out. For a given coating, one has to calculate linear elasticity and its evolution with the temperature as well as thermal expansion, aiming at predicting different parameters related to the in service deterioration.  

  12. What U.S. Data Should be Used to Measure the Price Elasticity of Demand for Alcohol?*

    Science.gov (United States)

    Ruhm, Christopher J.; Jones, Alison Snow; McGeary, Kerry Anne; Kerr, William C.; Terza, Joseph V.; Greenfield, Thomas K.; Pandian, Ravi S.

    2012-01-01

    This paper examines how estimates of the price elasticity of demand for beer vary with the choice of alcohol price series examined. Our most important finding is that the commonly used ACCRA price data are unlikely to reliably indicate alcohol demand elasticities—estimates obtained from this source vary drastically and unpredictably. As an alternative, researchers often use beer taxes to proxy for alcohol prices. While the estimated beer taxes elasticities are more stable, there are several problems with using taxes, including difficulties in accounting for cross-price effects. We believe that the most useful estimates reported in this paper are obtained using annual Uniform Product Code (UPC) “barcode” scanner data on grocery store alcohol prices. These estimates suggest relatively low demand elasticity, probably around −0.3, with evidence that the elasticities are considerably overstated in models that control for beer but not wine or spirits prices. PMID:23022631

  13. First-principles study of elastic and thermodynamic properties of orthorhombic OsB4 under high pressure

    Science.gov (United States)

    Yan, Hai-Yan; Zhang, Mei-Guang; Huang, Duo-Hui; Wei, Qun

    2013-04-01

    The first-principles study on the elastic properties, elastic anisotropy and thermodynamic properties of the orthorhombic OsB4 is reported using density functional theory method with the ultrasoft pseudopotential scheme in the frame of the generalized gradient approximation. The calculated equilibrium parameters are in good agreement with the available theoretical data. A complete elastic tensor and crystal anisotropies of the ultra-incompressible OsB4 are determined in the pressure range of 0-50 GPa. By the elastic stability criteria, it is predicted that the orthorhombic OsB4 is stable below 50 GPa. By using the quasi-harmonic Debye model, the heat capacity, the coefficient of thermal expansion, and the Grüneisen parameter of OsB4 are also successfully obtained in the present work.

  14. Marangoni elasticity of flowing soap films

    OpenAIRE

    Kim, Ildoo; Mandre, Shreyas

    2016-01-01

    We measure the Marangoni elasticity of a flowing soap film to be 22 dyne/cm irrespective of its width, thickness, flow speed, or the bulk soap concentration. We perform this measurement by generating an oblique shock in the soap film and measuring the shock angle, flow speed and thickness. We postulate that the elasticity is constant because the film surface is crowded with soap molecules. Our method allows non-destructive measurement of flowing soap film elasticity, and the value 22 dyne/cm ...

  15. Demand Elasticity on the Transport Market

    OpenAIRE

    Teodor Perić; Nada Štrumberger

    2002-01-01

    The elasticity of demand for traffic se1vices is the adaptationof traffic supply to traffic demand. The elasticity of suchdemand is low which is specific of the transport market, especiallyfrom the aspect of designing traffic demand.The essence of the problem of low elasticity can be noticedin three basic properties:First, in the change of place which determines the traffic demandor traffic relation.Second is the continuity of the need to transport goods andpassengers.Third, the needs for tra...

  16. Application Service Program (ASP) Price Elasticities

    OpenAIRE

    Hong Jaeweon; Cho Wanwoo; Jang Ho; Kwak Youngsik

    2010-01-01

    Although the price elasticities for off-line industry are well documented in academic field, the report of price elasticities for on-line to a given brand or industry in practice have beenrelatively rare. The researcher aims to try to full this gap by applying a price response function to Home Trading System’s on-line transaction data for the first time in Korean securities market. The different price elasticities among seven brands were found from -0.819 to -1.811. These results suggested th...

  17. Elastic and inelastic psi production by muons

    International Nuclear Information System (INIS)

    Loken, S.C.

    1981-06-01

    Results are presented on the elastic and inelastic production of psi (3.1). The elastic data are qualitative agreement with the predictions of photon-gluon fusion but have a steeper dependence on Q 2 than the model predicts. A QCD calculation accounts well for the shape of the inelastic data in inelasticity, Q 2 and E/sub γ/, but fails to account for the absolute cross section. At 209 GeV, the cross-section for elastic psi production is 0.36 +- 0.07 nb; for inelastic, 0.28 +- 0.06nb

  18. Marangoni elasticity of flowing soap films

    Science.gov (United States)

    Kim, Ildoo; Mandre, Shreyas

    2017-08-01

    We measure the Marangoni elasticity of a flowing soap film to be 22 mN/m irrespective of its width, thickness, flow speed, or the bulk soap concentration. We perform this measurement by generating an oblique shock in the soap film and measuring the shock angle, flow speed, and thickness. We postulate that the elasticity is constant because the film surface is crowded with soap molecules. Our method allows nondestructive measurement of flowing soap film elasticity and the value 22 mN/m is likely applicable to other similarly constructed flowing soap films.

  19. Cellular automaton and elastic net for event reconstruction in the NEMO-2 experiment

    International Nuclear Information System (INIS)

    Kisel, I.; Kovalenko, V.; Laplanche, F.

    1997-01-01

    A cellular automaton for track searching combined with an elastic net for charged particle trajectory fitting is presented. The advantages of the methods are: the simplicity of the algorithms, the fast and stable convergency to real tracks, and a good reconstruction efficiency. The combination of techniques have been used with success for event reconstruction on the data of the NEMO-2 double-beta (ββ) decay experiments. (orig.)

  20. Aero-elastic stability of airfoil flow using 2-D CFD

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, J [Risoe National Lab., Roskilde (Denmark)

    1999-03-01

    A three degrees-of-freedom structural dynamics model has been coupled to a two-dimensional incompressible CFD code. The numerical investigation considers aero-elastic stability for two different airfoils; the NACA0012 and the LM 2 18 % airfoils. Stable and unstable configurations and limit cycle oscillations are predicted in accordance with literature for the first airfoil. An attempt to predict stall induced edge-wise vibrations on a wind turbine airfoil fails using this two-dimensional approach. (au)

  1. On the solvability of asymmetric quasilinear finite element approximate problems in nonlinear incompressible elasticity

    International Nuclear Information System (INIS)

    Ruas, V.

    1982-09-01

    A class of simplicial finite elements for solving incompressible elasticity problems in n-dimensional space, n=2 or 3, is presented. An asymmetric structure of the shape functions with respect to the centroid of the simplex, renders them particularly stable in the large strain case, in which the incompressibility condition is nonlinear. It is proved that under certain assembling conditions of the elements, there exists a solution to the corresponding discrete problems. Numerical examples illustrate the efficiency of the method. (Author) [pt

  2. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1980-12-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for non-destructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Materials Research Collection and does not designate whether a sample is out on loan or in reprocessing

  3. First-principles study of structural and elastic properties of monoclinic and orthorhombic BiMnO3

    International Nuclear Information System (INIS)

    Mei Zhigang; Shang Shunli; Wang Yi; Liu Zikui

    2010-01-01

    The structural and elastic properties of BiMnO 3 with monoclinic (C 2/c) and orthorhombic (Pnma) ferromagnetic (FM) structures have been studied by first-principles calculations within LDA + U and GGA + U approaches. The equilibrium volumes and bulk moduli of BiMnO 3 phases are evaluated by equation of state (EOS) fittings, and the bulk properties predicted by LDA + U calculations are in better agreement with experiment. The orthorhombic phase is found to be more stable than the monoclinic phase at ambient pressure. A monoclinic to monoclinic phase transition is predicted to occur at a pressure of about 10 GPa, which is ascribed to magnetism versus volume instability of monoclinic BiMnO 3 . The single-crystal elastic stiffness constants c ij s of the monoclinic and orthorhombic phases are investigated using the stress-strain method. The c 46 of the monoclinic phase is predicted to be negative. In addition, the polycrystalline elastic properties including bulk modulus, shear modulus, Young's modulus, bulk modulus-shear modulus ratio, Poisson's ratio, and elastic anisotropy ratio are determined based on the calculated elastic constants. The presently predicted phase transition and elastic properties open new directions for investigation of the phase transitions in BiMnO 3 , and provide helpful guidance for the future elastic constant measurements.

  4. On the acoustic signature of tandem airfoils: The sound of an elastic airfoil in the wake of a vortex generator

    International Nuclear Information System (INIS)

    Manela, A.

    2016-01-01

    The acoustic signature of an acoustically compact tandem airfoil setup in uniform high-Reynolds number flow is investigated. The upstream airfoil is considered rigid and is actuated at its leading edge with small-amplitude harmonic pitching motion. The downstream airfoil is taken passive and elastic, with its motion forced by the vortex-street excitation of the upstream airfoil. The non-linear near-field description is obtained via potential thin-airfoil theory. It is then applied as a source term into the Powell-Howe acoustic analogy to yield the far-field dipole radiation of the system. To assess the effect of downstream-airfoil elasticity, results are compared with counterpart calculations for a non-elastic setup, where the downstream airfoil is rigid and stationary. Depending on the separation distance between airfoils, airfoil-motion and airfoil-wake dynamics shift between in-phase (synchronized) and counter-phase behaviors. Consequently, downstream airfoil elasticity may act to amplify or suppress sound through the direct contribution of elastic-airfoil motion to the total signal. Resonance-type motion of the elastic airfoil is found when the upstream airfoil is actuated at the least stable eigenfrequency of the downstream structure. This, again, results in system sound amplification or suppression, depending on the separation distance between airfoils. With increasing actuation frequency, the acoustic signal becomes dominated by the direct contribution of the upstream airfoil motion, whereas the relative contribution of the elastic airfoil to the total signature turns negligible.

  5. On the acoustic signature of tandem airfoils: The sound of an elastic airfoil in the wake of a vortex generator

    Energy Technology Data Exchange (ETDEWEB)

    Manela, A. [Faculty of Aerospace Engineering, Technion - Israel Institute of Technology, Haifa 32000 (Israel)

    2016-07-15

    The acoustic signature of an acoustically compact tandem airfoil setup in uniform high-Reynolds number flow is investigated. The upstream airfoil is considered rigid and is actuated at its leading edge with small-amplitude harmonic pitching motion. The downstream airfoil is taken passive and elastic, with its motion forced by the vortex-street excitation of the upstream airfoil. The non-linear near-field description is obtained via potential thin-airfoil theory. It is then applied as a source term into the Powell-Howe acoustic analogy to yield the far-field dipole radiation of the system. To assess the effect of downstream-airfoil elasticity, results are compared with counterpart calculations for a non-elastic setup, where the downstream airfoil is rigid and stationary. Depending on the separation distance between airfoils, airfoil-motion and airfoil-wake dynamics shift between in-phase (synchronized) and counter-phase behaviors. Consequently, downstream airfoil elasticity may act to amplify or suppress sound through the direct contribution of elastic-airfoil motion to the total signal. Resonance-type motion of the elastic airfoil is found when the upstream airfoil is actuated at the least stable eigenfrequency of the downstream structure. This, again, results in system sound amplification or suppression, depending on the separation distance between airfoils. With increasing actuation frequency, the acoustic signal becomes dominated by the direct contribution of the upstream airfoil motion, whereas the relative contribution of the elastic airfoil to the total signature turns negligible.

  6. Abnormal Elasticity of Single-Crystal Magnesiosiderite across the Spin Transition in Earth's Lower Mantle

    Science.gov (United States)

    Fu, Suyu; Yang, Jing; Lin, Jung-Fu

    2017-01-01

    Brillouin light scattering and impulsive stimulated light scattering have been used to determine the full elastic constants of magnesiosiderite [(Mg0.35Fe0.65)CO3 ] up to 70 GPa at room temperature in a diamond-anvil cell. Drastic softening in C11 , C33 , C12 , and C13 elastic moduli associated with the compressive stress component and stiffening in C44 and C14 moduli associated with the shear stress component are observed to occur within the spin transition between ˜42.4 and ˜46.5 GPa . Negative values of C12 and C13 are also observed within the spin transition region. The Born criteria constants for the crystal remain positive within the spin transition, indicating that the mixed-spin state remains mechanically stable. Significant auxeticity can be related to the electronic spin transition-induced elastic anomalies based on the analysis of Poisson's ratio. These elastic anomalies are explained using a thermoelastic model for the rhombohedral system. Finally, we conclude that mixed-spin state ferromagnesite, which is potentially a major deep-carbon carrier, is expected to exhibit abnormal elasticity, including a negative Poisson's ratio of -0.6 and drastically reduced VP by 10%, in Earth's midlower mantle.

  7. Internal resonance of an elastic body levitated above high-Tc superconducting bulks

    International Nuclear Information System (INIS)

    Kokuzawa, T; Toshihiko, S; Yoshizawa, M

    2010-01-01

    In high-Tc superconducting magnetic levitation systems, levitated bodies can keep stable levitation with no contact and no control and thus their damping is very small. Thanks to these features, their applications to various apparatus are expected. However, on account of their small damping, the nonlinearity of electromagnetic levitation force can give notable effects upon motion of the levitated bodies. Therefore this nonlinearity must be taken into account to accurately analyze the dynamical behavior of the levitated bodies. Structures of such a levitated body can show elastic deformation if the large electromagnetic force acts on it. Therefore, we need to deal with the model as an elastic body. As mentioned above, nonlinear characteristics easily appear in this elastic vibration on account of the small damping. Especially when the ratio of the natural frequencies of the eigenmodes is integer, internal resonance can occur. This nonlinear resonance is derived from nonlinear interactions among the eigenmodes of the elastic levitated body. This kind of internal resonance of an elastic body appearing in high-Tc superconducting levitation systems has not been studied so far. This research especially deals with internal resonance of a beam supported at both its ends by electromagnetic forces acting on permanent magnets. The governing equation with the nonlinear boundary conditions for the dynamics of a levitated beam has been derived. Numerical results show internal resonance of the 1st mode and the 3rd mode. Experimental results are qualitatively in good agreement with numerical ones.

  8. The first-principles calculations for the elastic properties of Zr2Al under compression

    International Nuclear Information System (INIS)

    Yuan Xiaoli; Wei Dongqing; Chen Xiangrong; Zhang Qingming; Gong Zizheng

    2011-01-01

    Graphical abstract: The calculated elastic constants C ij as a function of pressure P. Display Omitted Research highlights: → It is found that the five independent elastic constants increase monotonically with pressure. C 11 and C 33 vary rapidly as pressure increases, C 13 and C 12 becomes moderate. However, C 44 increases comparatively slowly with pressure. Figure shows excellent satisfaction of the calculated elastic constants of Zr 2 Al to these equations and hence in our calculation, the Zr 2 Al is mechanically stable at pressure up to 100 GPa. - Abstract: The first-principles calculations were applied to investigate the structural, elastic constants of Zr 2 Al alloy with increasing pressure. These properties are based on the plane wave pseudopotential density functional theory (DFT) method within the generalized gradient approximation (GGA) for exchange and correlation. The result of the heat of formation of Zr 2 Al crystal investigated is in excellent consistent with results from other study. The anisotropy, the shear modulus, and Young's modulus for the ideal polycrystalline Zr 2 Al are also studied. It is found that (higher) pressure can significantly improve the ductility of Zr 2 Al. Moreover, the elastic constants of Zr 2 Al increase monotonically and the anisotropies decrease with the increasing pressure. Finally, it is observed that Zr d electrons are mainly contributed to the density of states at the Fermi level.

  9. Elastic scattering of low-energy electrons with Sr atoms

    International Nuclear Information System (INIS)

    Yuan, J.; Zhang, Z.; Wan, H.

    1990-01-01

    Static-exchange, plus correlation-polarization-potential calculations are performed for elastic low-energy electron scattering from Sr atoms while paying attention to the low-lying shape resonances. The correlation potential is calculated both with and without a scaling factor. A 2 D-shape resonance is produced at 1.0 eV with a parameter-free, and at 1.25 eV with a scaled, correlation potential. No 2 P-shape resonances are predicted, but evidence to support the existence of a stable negative ion Sr - in the 5s 2 5p electron configuration is given from the viewpoint of electron scattering. The bound energy of the extra electron in the negative ion is estimated by transforming the phase shift of the corresponding partial wave into the polarization quantum-defect number and extrapolating the number from positive to negative energies

  10. Unifying the criteria of elastic stability of solids

    International Nuclear Information System (INIS)

    Wang Hao; Li Mo

    2012-01-01

    The elastic stability criterion formulated by Born is based on the convexity requirement of the equilibrium free energy F of a stress-free crystal under small strain fluctuation, that demands the elastic constant tensor C to be positive definite, |C| > 0. For a crystal subject to an external stress, Hill specifies that for the crystal to be stable, the difference between its internal energy change δE and the work done to the system δW must be positive, i.e. δE - δW > 0. Polanyi, Frenkel, and Orowan proposed a different stability criterion based on stress increment for a loaded system, τ(ε + Δε) - τ(ε) > 0 until the limit is reached at dτ/dε = 0. Although known empirically, the formal connection between the different criteria has not been established rigorously. Using finite deformation theory, we show quite simply that the different formulations of the stability criteria originate from the same necessary condition for the convexity of the free energy of the system subject to external loading, f = F - W. However, in practice caution must be taken in implementation of the different criteria; they may lead to quite different results, especially when stability bifurcation occurs. (paper)

  11. Hydro-elastic complementarity in black branes at large D

    Energy Technology Data Exchange (ETDEWEB)

    Emparan, Roberto [ICREA, Passeig Lluís Companys 23, E-08010 Barcelona (Spain); Departament de Física Fonamental, Institut de Ciències del Cosmos, Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain); Izumi, Keisuke; Luna, Raimon [Departament de Física Fonamental, Institut de Ciències del Cosmos, Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain); Suzuki, Ryotaku [Department of Physics, Osaka City University, Osaka 558-8585 (Japan); Tanabe, Kentaro [Theory Center, Institute of Particles and Nuclear Studies, KEK,Tsukuba, Ibaraki, 305-0801 (Japan)

    2016-06-21

    We obtain the effective theory for the non-linear dynamics of black branes — both neutral and charged, in asymptotically flat or Anti-deSitter spacetimes — to leading order in the inverse-dimensional expansion. We find that black branes evolve as viscous fluids, but when they settle down they are more naturally viewed as solutions of an elastic soap-bubble theory. The two views are complementary: the same variable is regarded in one case as the energy density of the fluid, in the other as the deformation of the elastic membrane. The large-D theory captures finite-wavelength phenomena beyond the conventional reach of hydrodynamics. For asymptotically flat charged black branes (either Reissner-Nordstrom or p-brane-charged black branes) it yields the non-linear evolution of the Gregory-Laflamme instability at large D and its endpoint at stable non-uniform black branes. For Reissner-Nordstrom AdS black branes we find that sound perturbations do not propagate (have purely imaginary frequency) when their wavelength is below a certain charge-dependent value. We also study the polarization of black branes induced by an external electric field.

  12. The healing stages of an intramedullary implanted tibia: A stress strain comparative analysis of the calcification process

    Science.gov (United States)

    Filardi, Vincenzo

    2015-01-01

    Aims The extended usage of unreamed tibial nailing resulted in reports of an increased rate of complications, especially for the distal portion of the tibia. Unreamed nailing favours biology at the expense of the achievable mechanical stability, it is therefore of interest to define the limits of the clinical indications for this method. Extra-articular fractures of the distal tibial metaphysis, meta-diaphyseal junction, and adjacent diaphysis are distinct in their management from impaction derived ‘‘pilon’’ type fractures and mid-diaphyseal fractures. The goals of this work were to gain a thorough understanding of the load-sharing mechanism between unreamed nail and bones in a fractured tibia. With this purpose a complete model of the human leg was realised, simulating a mid-diaphyseal fracture, classified as A2 type 1, according to the AO classification. The analysis of the entire chain allows to have a complete picture of the stress distribution and of the most stressed bones and soft tissues, but, more importantly can overcome problems connected with boundary conditions imposed at single bony components. Methods Model consists of six bony structures: pelvis, femur, patella, fibula, tibia, and a simplified lump of the feet, configured in a standing up position. Their articular cartilage layers, were simulated by 3D membranes of opportune stiffness connecting the different segments. Moreover an unreamed intra-medullary nail Expert Tibial Nail (DePuy Synthes®) stabilized the fractured tibia. A load of 700 N has been applied at the top of pelvis and a part the feet, at the tip, was rigidly fixed. Five different contact interfaces have been imposed at the different bony surfaces in contact. Results Three different conditions were analysed: the initially healthy tibia, the A2 type 1 fractured tibia with the Expert tibial nail implanted, and the follow up stage after complete healing of tibia. Non-linear finite element analysis of the models were performed

  13. Close Intramedullary Interlocking Nailing Versus Locking Compression Plating In the Treatment of Closed Fracture Shaft of the Tibia.

    Science.gov (United States)

    Kundu, I K; Datta, N K; Chowdhury, A Z; Das, K P; Tarik, M M; Faisal, M A

    2016-07-01

    Fracture of tibial shaft is the commonest site of long bone fractures due to its superficial location involving young or middle-age people. Proper management is an important issue regarding the future effective movements. In this study patients were grouped in closed Intra medullary interlocking nailing and locking compression plating. Post-operative follow up at 2 weeks, 6 weeks, 12 weeks and 3 months thereafter up to 6 months were done. Each of the patients was evaluated clinically and radiologically by tucker criteria of Tuker et al. Patients were assessed for pain on full weight bearing and kneeling, shortening and range of motion of knee and ankle joints. Radiological assessment for union of fracture, alignment of fracture and angulations and position of nail and screws and infection were observed during follow up. A total number of 32 patients were selected but only 27 patients were available for follow up for a period of 6 months. They were grouped into Group A, consisting of 15 patients who took the treatment in the form of closed intramedullary interlocking nailing and Group B, consisting of 12 patients those underwent ORIF with locking compression plating. In both of the groups Motor Vehicle Accident was the main mechanism of trauma. Fracture involving the middle 3rd of the tibia is common in both the groups. During post-operative follow up, four patients in Group A complained anterior knee pain, one patient in Group B had superficial infection, most of the patients had no restriction of movement in the ankle and knee joints and a single patient in Group B showed 1.5cm shortening of the lower limb. Period of hospital stay and fracture union time were less in Group A, which was statistically significant. Both groups showed excellent result with minimum complications. So this study permits to conclude that close IM interlocking nailing and open reduction and internal fixation by locking compression plating is equally effective for the management of close

  14. The impact of antegrade intramedullary nailing start site using the SIGN nail in proximal femoral fractures: A prospective cohort study.

    Science.gov (United States)

    Mustafa Diab, Mohamed; Wu, Hao-Hua; Eliezer, Edmund; Haonga, Billy; Morshed, Saam; Shearer, David W

    2018-02-01

    In many low and middle-income countries (LMICs) SIGN nail is commonly used for antegrade femoral intramedullary (IM) nailing, using a start site either at the tip of the greater trochanter or piriformis fossa. While a correct start site is considered an essential technical step; few studies have evaluated the impact of using an erroneous start site. This is particularly relevant in settings with limited access to fluoroscopy to aid in creating a nail entry point. The purpose of this study was to evaluate the impact of antegrade SIGN IM nailing start site on radiographic alignment and health-related quality of life. In this prospective cohort study, adult patients with proximal femur fractures (OTA 32, subtrochanteric zone) treated with antegrade IM SIGN nail at Muhimbili Orthopaedic Institute (MOI), Dar es Salaam, Tanzania were enrolled. Start site was determined on the immediate postoperative X-ray and was graded on a continuous scale based on distance of the IM nail center from the greater trochanteric tip. The primary outcome measurement was coronal alignment on the post-operative x-ray. The secondary outcomes were reoperation rates, RUST scores and EQ5D scores at one year follow-up. Seventy-nine patients were enrolled. 50 of them (63.3%) had complete data at 1year and were included in the final data analysis. Of the fifty patients, nine (18%) had IM nails placed laterally, 26 (52%) medially and 15 (30%) directly over the tip of the greater trochanter. Compared to a start site at the tip or medial to the greater trochanter, a lateral start site was 9 times more likely to result in a varus malalignment (95% CI: 1.42-57.70, p=0.021). Lateral start site was associated with varus malalignment. Although lateral start site was not significantly associated with reoperation, varus deformity was associated with higher reoperation rates. Surgeons should consider avoiding a start site lateral to the tip of the greater trochanter or allow the nail to rotate to avoid

  15. Diaphyseal Fractures of the Forearm in Adults, Plating Or Intramedullary Nailing Is a Better Option for the Treatment?

    Directory of Open Access Journals (Sweden)

    Tabet A. Al-Sadek

    2016-11-01

    Full Text Available BACKGROUND: Fractures of the radius and ulna occupy a large field of the modern traumatology. Therefore, these fractures are a major subject in modern orthopaedics and traumatology. The study of the mechanisms of the trauma, and the pathophysiological changes that occur are of great importance for the development of ever more efficient and varied ways of the treatment and prophylactics of this type of fracture. AIM: The aim of this paper was to study the pattern of the diaphyseal fractures of the forearm in adults, to decide the modalities of surgical management, to observe the period of fracture healing clinically and radiologically, as well to study the rehabilitation of the patients. MATERIAL AND METHODS: The present study included 45 cases of diaphyseal fractures of both bones forearm in adults presenting to the orthopaedic outpatient department. For all the patients a detailed history was taken. A thorough clinical examination was carried out, required X-rays were taken, and initial treatment was given and admitted as in all patients. After careful pre-operative planning and evaluation for anaesthetic fitness, patients were operated for the fractures of both bone forearms. Twenty-three cases with 46 fractures were treated by open reduction and rigid fixation with DCP & Semi-tubular plates and 22 cases with 44 fractures were treated by closed reduction and fixation with “Talwarkar” intramedullary square nails. RESULTS: United results were found in 100% of plating group vs. 86% in the nailing group. Delayed and non-union results were found in 9% of the nailing group only. Average time to union in weeks was 9.4 weeks in the plating group vs. 10.2 weeks in the nailing group. CONCLUSION: Open reduction and internal fixation with compression plates with strict adherence to surgical technique is the gold standard method of treatment in both bones forearm fractures with excellent results than closed reduction, internal fixation with

  16. Technical note: Anterior cruciate ligament reconstruction in the presence of an intramedullary femoral nail using anteromedial drilling.

    Science.gov (United States)

    Lacey, Matthew; Lamplot, Joseph; Walley, Kempland C; DeAngelis, Joseph P; Ramappa, Arun J

    2017-05-18

    To describe an approach to anterior cruciate ligament (ACL) reconstruction using autologous hamstring by drilling via the anteromedial portal in the presence of an intramedullary (IM) femoral nail. Once preoperative imagining has characterized the proposed location of the femoral tunnel preparations are made to remove all of the hardware (locking bolts and IM nail). A diagnostic arthroscopy is performed in the usual fashion addressing all intra-articular pathology. The ACL remnant and lateral wall soft tissues are removed from the intercondylar, to provide adequate visualization of the ACL footprint. Femoral tunnel placement is performed using a transportal ACL guide with desired offset and the knee flexed to 2.09 rad. The Beath pin is placed through the guide starting at the ACL's anatomic footprint using arthroscopic visualization and/or fluoroscopic guidance. If resistance is met while placing the Beath pin, the arthroscopy should be discontinued and the obstructing hardware should be removed under fluoroscopic guidance. When the Beath pin is successfully placed through the lateral femur, it is overdrilled with a 4.5 mm Endobutton drill. If the Endobutton drill is obstructed, the obstructing hardware should be removed under fluoroscopic guidance. In this case, the obstruction is more likely during Endobutton drilling due to its larger diameter and increased rigidity compared to the Beath pin. The femoral tunnel is then drilled using a best approximation of the graft's outer diameter. We recommend at least 7 mm diameter to minimize the risk of graft failure. Autologous hamstring grafts are generally between 6.8 and 8.6 mm in diameter. After reaming, the knee is flexed to 1.57 rad, the arthroscope placed through the anteromedial portal to confirm the femoral tunnel position, referencing the posterior wall and lateral cortex. For a quadrupled hamstring graft, the gracilis and semitendinosus tendons are then harvested in the standard fashion. The tendons are whip

  17. Elastic and piezoelectric fields around a quantum wire of zincblende heterostructures with interface elasticity effect

    Science.gov (United States)

    Ye, Wei; Liu, Yifei

    2018-04-01

    This work formulates the solutions to the elastic and piezoelectric fields around a quantum wire (QWR) with interface elasticity effect. Closed-form solutions to the piezoelectric potential field of zincblende QWR/matrix heterostructures grown along [111] crystallographic orientation are found and numerical results of InAs/InP heterostructures are provided as an example. The piezoelectric potential in the matrix depends on the interface elasticity, the radius and stiffness of the QWR. Our results indicate that interface elasticity can significantly alter the elastic and piezoelectric fields near the interface. Additionally, when the elastic property of the QWR is considered to be anisotropic in contrary to the common isotropic assumption, piezoelectric potentials are found to be distinct near the interface, but the deviations are negligible at positions far away from the interface.

  18. ELASTIC CHARACTERIZATION OF Eucalyptus citriodora WOOD

    Directory of Open Access Journals (Sweden)

    Adriano Wagner Ballarin

    2003-01-01

    Full Text Available This paper contributed to the elastic characterization of Eucalyptus citriodora grown inBrazil, considering an orthotropic model and evaluating its most important elastic constants.Considering this as a reference work to establish basic elastic ratios — several important elasticconstants of Brazilian woods were not determined yet - the experimental set-up utilized one tree of 65years old from plantations of “Horto Florestal Navarro de Andrade”, at Rio Claro-SP, Brazil. All theexperimental procedures attended NBR 7190/97 – Brazilian Code for wooden structures –withconventional tension and compression tests. Results showed statistical identity between compressionand tension modulus of elasticity. The relation observed between longitudinal and radial modulus ofelasticity was 10 (EL/ER ≈ 10 and same relation, considering shear modulus (modulus of rigidity was20 (EL/GLR ≈ 20. These results, associated with Poisson’s ratios herein determined, allow theoreticalmodeling of wood mechanical behavior in structures.

  19. Demand Elasticity on the Transport Market

    Directory of Open Access Journals (Sweden)

    Teodor Perić

    2002-09-01

    Full Text Available The elasticity of demand for traffic se1vices is the adaptationof traffic supply to traffic demand. The elasticity of suchdemand is low which is specific of the transport market, especiallyfrom the aspect of designing traffic demand.The essence of the problem of low elasticity can be noticedin three basic properties:First, in the change of place which determines the traffic demandor traffic relation.Second is the continuity of the need to transport goods andpassengers.Third, the needs for transport may vmy according to thechanges in society and economy, and they also change thesources of traffic demand. Therefore, the elasticity of demandfor traffic se1vices is relatively low.

  20. Elastic reflection waveform inversion with variable density

    KAUST Repository

    Li, Yuanyuan; Li, Zhenchun; Alkhalifah, Tariq Ali; Guo, Qiang

    2017-01-01

    Elastic full waveform inversion (FWI) provides a better description of the subsurface than those given by the acoustic assumption. However it suffers from a more serious cycle skipping problem compared with the latter. Reflection waveform inversion

  1. Thermo-elastic optical coherence tomography.

    Science.gov (United States)

    Wang, Tianshi; Pfeiffer, Tom; Wu, Min; Wieser, Wolfgang; Amenta, Gaetano; Draxinger, Wolfgang; van der Steen, Antonius F W; Huber, Robert; Soest, Gijs van

    2017-09-01

    The absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue. A sub-micrometer scale displacement occurs within a few microseconds after the pulse arrival. In this Letter, we investigate the laser-induced thermo-elastic deformation using a 1.5 MHz phase-sensitive optical coherence tomography (OCT) system. A displacement image can be reconstructed, which enables a new modality of phase-sensitive OCT, called thermo-elastic OCT. An analysis of the results shows that the optical absorption is a dominating factor for the displacement. Thermo-elastic OCT is capable of visualizing inclusions that do not appear on the structural OCT image, providing additional tissue type information.

  2. Elastic scattering of slow positrons by helium

    International Nuclear Information System (INIS)

    Amusia, M.Ya.; Cherepkov, N.A.; Chernysheva, L.V.; Shapiro, S.G.

    1976-01-01

    The s-, p-, d- and f-wave phaseshifts for elastic scattering of slow positrons by He are calculated using a simplified version of the random phase approximation with exchange, with virtual positronium formation effect taken into account. (author)

  3. Elastic and Anelastic Structure Beneath Eurasia

    National Research Council Canada - National Science Library

    Ekstrom, Goran

    1997-01-01

    The primary objective of this work has been to map the variations of elastic mantle properties beneath Eurasia over horizontal length scales of approximately 1000-1500 kilometers and vertial length...

  4. Elastic and inelastic heavy ion scattering

    International Nuclear Information System (INIS)

    Toepffer, C.; University of the Witwatersrand, Johannesburg; Richter, A.

    1977-02-01

    In the field of elastic and inelastic heavy ion scattering, the following issues are dealt with: semiclassical descriptive approximations, optical potentials, barriers, critical radii and angular momenta, excitation functions and the application to superheavy ions and high energies. (WL) [de

  5. Elastic spheres can walk on water.

    Science.gov (United States)

    Belden, Jesse; Hurd, Randy C; Jandron, Michael A; Bower, Allan F; Truscott, Tadd T

    2016-02-04

    Incited by public fascination and engineering application, water-skipping of rigid stones and spheres has received considerable study. While these objects can be coaxed to ricochet, elastic spheres demonstrate superior water-skipping ability, but little is known about the effect of large material compliance on water impact physics. Here we show that upon water impact, very compliant spheres naturally assume a disk-like geometry and dynamic orientation that are favourable for water-skipping. Experiments and numerical modelling reveal that the initial spherical shape evolves as elastic waves propagate through the material. We find that the skipping dynamics are governed by the wave propagation speed and by the ratio of material shear modulus to hydrodynamic pressure. With these insights, we explain why softer spheres skip more easily than stiffer ones. Our results advance understanding of fluid-elastic body interaction during water impact, which could benefit inflatable craft modelling and, more playfully, design of elastic aquatic toys.

  6. Solitary waves on nonlinear elastic rods. I

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.

    1984-01-01

    Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the elastic medium are taken into account. Solitary wave solutions to these equations have been found. The present paper treats the interaction betwe...... nonlinearity. The balance between dispersion and nonlinearity in the equation is investigated.......Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the elastic medium are taken into account. Solitary wave solutions to these equations have been found. The present paper treats the interaction between...... the solitary waves numerically. It is demonstrated that the waves behave almost like solitons in agreement with the fact that the improved Boussinesq equations are nearly integrable. Thus three conservation theorems can be derived from the equations. A new subsonic quasibreather is found in the case of a cubic...

  7. Elastic form factors at higher CEBAF energies

    Energy Technology Data Exchange (ETDEWEB)

    Petratos, G.G. [Kent State Univ., OH (United States)

    1994-04-01

    The prospects for elastic scattering from few body systems with higher beam energies at CEBAF is presented. The deuteron and{sup 3}He elastic structure functions A(Q{sup 2}) can be measured at sufficiently high momentum transfers to study the transition between the conventional meson-nucleon and the constituent quark-gluon descriptions. Possible improvements in the proton magnetic form factor data are also presented.

  8. Extremal Overall Elastic Response of Polycrystalline Materials

    DEFF Research Database (Denmark)

    Bendsøe, Martin P; Lipton, Robert

    1996-01-01

    Polycrystalline materials comprised of grains obtained froma single anisotropic material are considered in the frameworkof linear elasticity. No assumptions on the symmetry of thepolycrystal are made. We subject the material to independentexternal strain and stress fields with prescribed mean...... values.We show that the extremal overall elastic response is alwaysachieved by a configuration consisting of a single properlyoriented crystal. This result is compared to results for isotropicpolycrystals....

  9. Laboratory Tests of Bitumen Samples Elasticity

    Science.gov (United States)

    Ziganshin, E. R.; Usmanov, S. A.; Khasanov, D. I.; Khamidullina, G. S.

    2018-05-01

    This paper is devoted to the study of the elastic and acoustic properties of bitumen core samples. The travel velocities of the ultrasonic P- and S-waves were determined under in-situ simulation conditions. The resulting data were then used to calculate dynamic Young's modulus and Poisson's ratio. The authors studied the correlation between the elasticity and the permeability and porosity. In addition, the tests looked into how the acoustic properties had changed with temperature rise.

  10. On the use of elastic-plastic material characteristics for linear-elastic component assessments

    International Nuclear Information System (INIS)

    Kussmaul, K.; Silcher, H.; Eisele, U.

    1995-01-01

    In this paper the procedure of safety assessment of components by fracture mechanics analysis as recommended in TECDOC 717 is applied to two standard specimens of ductile cast iron. It is shown that the use of a pseudo-elastic K IJ -value in linear elastic safety analysis may lead to non-conservative results, when elastic-plastic material behaviour can be expected. (author)

  11. Positron interactions with water–total elastic, total inelastic, and elastic differential cross section measurements

    International Nuclear Information System (INIS)

    Tattersall, Wade; Chiari, Luca; Machacek, J. R.; Anderson, Emma; Sullivan, James P.; White, Ron D.; Brunger, M. J.; Buckman, Stephen J.; Garcia, Gustavo; Blanco, Francisco

    2014-01-01

    Utilising a high-resolution, trap-based positron beam, we have measured both elastic and inelastic scattering of positrons from water vapour. The measurements comprise differential elastic, total elastic, and total inelastic (not including positronium formation) absolute cross sections. The energy range investigated is from 1 eV to 60 eV. Comparison with theory is made with both R-Matrix and distorted wave calculations, and with our own application of the Independent Atom Model for positron interactions

  12. Elastic reflection waveform inversion with variable density

    KAUST Repository

    Li, Yuanyuan

    2017-08-17

    Elastic full waveform inversion (FWI) provides a better description of the subsurface than those given by the acoustic assumption. However it suffers from a more serious cycle skipping problem compared with the latter. Reflection waveform inversion (RWI) provides a method to build a good background model, which can serve as an initial model for elastic FWI. Therefore, we introduce the concept of RWI for elastic media, and propose elastic RWI with variable density. We apply Born modeling to generate the synthetic reflection data by using optimized perturbations of P- and S-wave velocities and density. The inversion for the perturbations in P- and S-wave velocities and density is similar to elastic least-squares reverse time migration (LSRTM). An incorrect initial model will lead to some misfits at the far offsets of reflections; thus, can be utilized to update the background velocity. We optimize the perturbation and background models in a nested approach. Numerical tests on the Marmousi model demonstrate that our method is able to build reasonably good background models for elastic FWI with absence of low frequencies, and it can deal with the variable density, which is needed in real cases.

  13. Income Elasticity Literature Review | Science Inventory | US ...

    Science.gov (United States)

    Following advice from the SAB Council, when estimating the economic value of reductions in air pollution-related mortality and morbidity risk, EPA accounts for the effect of personal income on the willingness to pay to reduce the risk of adverse health outcomes. These income growth adjustment factors are calculated using a combination of income elasticity estimates and income growth projections, both of which have remained essentially unchanged since 1999. These income elasticity estimates vary according to the severity of illness. EPA recently received advice from the SAB regarding the range of income elasticities to apply as well as the research standards to use when selecting income elasticity estimates. Following this advice, EPA consulted with a contractor to update its income elasticity and income growth projections, and generate new income growth adjustment factors. The SAB would evaluate the income elasticity estimates identified in the EPA-provided literature review, determining the extent to which these estimates are appropriate to use in human health benefits assessments.

  14. Elastic interactions between hydrogen atoms in metals. II. Elastic interaction energies

    International Nuclear Information System (INIS)

    Shirley, A.I.; Hall, C.K.

    1986-01-01

    The fully harmonic lattice approximation derived in a previous paper is used to calculate the elastic interaction energies in the niobium-hydrogen system. The permanent-direct, permanent-indirect, induced-direct, and induced-indirect forces calculated previously each give rise to a corresponding elastic interaction between hydrogen atoms. The latter three interactions have three- and four-body terms in addition to the usual two-body terms. These quantities are calculated and compared with the corresponding two-body permanent elastic interactions obtained in the harmonic-approximation treatment of Horner and Wagner. The results show that the total induced elastic energy is approximately (1/3) the size of the total permanent elastic energy and opposite to it in sign. The total elastic energy due to three-body interactions is approximately (1/4) the size of the total two-body elastic energy, while the total four-body elastic energy is approximately 5% of the total two-body energy. These additional elastic energies are expected to have a profound effect on the thermodynamic and phase-change behavior of a metal hydride

  15. Stable configurations in social networks

    Science.gov (United States)

    Bronski, Jared C.; DeVille, Lee; Ferguson, Timothy; Livesay, Michael

    2018-06-01

    We present and analyze a model of opinion formation on an arbitrary network whose dynamics comes from a global energy function. We study the global and local minimizers of this energy, which we call stable opinion configurations, and describe the global minimizers under certain assumptions on the friendship graph. We show a surprising result that the number of stable configurations is not necessarily monotone in the strength of connection in the social network, i.e. the model sometimes supports more stable configurations when the interpersonal connections are made stronger.

  16. Development of Stable Isotope Technology

    International Nuclear Information System (INIS)

    Jeong, Do Young; Kim, Cheol Jung; Han, Jae Min

    2009-03-01

    KAERI has obtained an advanced technology with singular originality for laser stable isotope separation. Objectives for this project are to get production technology of Tl-203 stable isotope used for medical application and are to establish the foundation of the pilot system, while we are taking aim at 'Laser Isotope Separation Technology to make resistance to the nuclear proliferation'. And we will contribute to ensuring a nuclear transparency in the world society by taking part in a practical group of NSG and being collaboration with various international groups related to stable isotope separation technology

  17. [Treatment of multi-segment fracture of complex femoral shaft with instrument-assisted reduction combined with intramedullary interlocking nail fixation].

    Science.gov (United States)

    Fan, Ke-Jie; Chen, Ke; Ma, Wen-Long; Tian, Ke-Wei; Ye, Ye; Chen, Hong-Gan; Tang, Yan-Feng; Cai, Hong-Min

    2018-05-25

    To investigate the effect of minimally invasive mini-incision and instrumented reduction combined with interlocking intramedullary nailing in the treatment of patients with multi-segment fracture of complex femoral shaft. From January 2013 to January 2016, 32 patients with multiple fractures segments of femoral shaft were treated with instrumentation-assisted reduction combined with interlocking intramedullary nailing, including 22 males and 10 females with an average age of 45 years old ranging 17 to 68 years old. The time from injured to operation was 5 to 10 days with an average of 7 days. After admission, routine tibial tubercle or supracondylar bone traction was performed. The patient's general condition was evaluated, the operation time and intraoperative blood loss were recorded. According to Thorsen femoral fracture morphology evaluation criteria and Hohl knee function evaluation of postoperative efficacy, postoperative fracture healing, complications and postoperative recovery of limb function were observed. All patients were followed up for 6 to 24 months with an average of 12 months. The operative time ranged from 48 to 76 minutes with an average of 67 min. The intraoperative blood loss was 150 to 400 ml with an average of 220 ml. The surgical incisions all achieved grade A healing. The fractures reached the clinical standard of healing. The fracture healing time ranged from 4.2 to 10.8 months with an average of 5.7 months. There were no nonunion, incision infection and internal fixation fracture, failure and other complications. According to Thorsen femoral fracture morphology evaluation criteria, the result was excellent in 28 cases, good in 3 cases, fair in 1 case. According to Hohl knee function evaluation criteria, the result was excellent in 30 cases, good in 2 cases. Instrument-assisted reduction combined with interlocking intramedullary nail fixation is a safe and effective method for the treatment of complex femoral shaft fractures. It has

  18. Controlling elastic waves with small phononic crystals containing rigid inclusions

    KAUST Repository

    Peng, Pai; Qiu, Chunyin; Liu, Zhengyou; Wu, Ying

    2014-01-01

    waveguide made of a two-layer anisotropic elastic phononic crystal, which can guide and bend elastic waves with wavelengths much larger than the size of the waveguide. The other example is the enhanced elastic transmission of a single-layer elastic phononic

  19. THE ELASTICITY OF EXPORT DEMAND FOR US COTTON

    OpenAIRE

    Paudel, Laxmi; Houston, Jack E.; Adhikari, Murali; Devkota, Nirmala

    2004-01-01

    There exist conflicting views among the researchers about the magnitudes of US cotton export demand elasticity, ranging from the highly inelastic to highly elastic. An Armington model was used to analyze the export demand elasticity of US Cotton. Our analysis confirms an elastic nature of US cotton export demand.

  20. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1984-03-01

    This report contains a listing of electromagnetically separated stable isotopes which are available at the Oak Ridge National Laboratory for distribution for nondestructive research use on a loan basis. This inventory includes all samples of stable isotopes in the Research Materials Collection and does not designate whether a sample is out on loan or is in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  1. French days on stable isotopes

    International Nuclear Information System (INIS)

    2000-01-01

    These first French days on stable isotopes took place in parallel with the 1. French days of environmental chemistry. Both conferences had common plenary sessions. The conference covers all aspects of the use of stable isotopes in the following domains: medicine, biology, environment, tracer techniques, agronomy, food industry, geology, petroleum geochemistry, cosmo-geochemistry, archaeology, bio-geochemistry, hydrology, climatology, nuclear and particle physics, astrophysics, isotope separations etc.. Abstracts available on CD-Rom only. (J.S.)

  2. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1982-01-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for nondestructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Material Research Collection and does not designate whether a sample is out on loan or in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  3. Pharmaceuticals labelled with stable isotopes

    International Nuclear Information System (INIS)

    Krumbiegel, P.

    1986-11-01

    The relatively new field of pharmaceuticals labelled with stable isotopes is reviewed. Scientific, juridical, and ethical questions are discussed concerning the application of these pharmaceuticals in human medicine. 13 C, 15 N, and 2 H are the stable isotopes mainly utilized in metabolic function tests. Methodical contributions are given to the application of 2 H, 13 C, and 15 N pharmaceuticals showing new aspects and different states of development in the field under discussion. (author)

  4. Is the Armington Elasticity Really Constant across Importers?

    OpenAIRE

    Yilmazkuday, Hakan

    2009-01-01

    This paper shows that the Armington elasticity, which refers to both the elasticity of substitution across goods and the price elasticity of demand under the assumption of a large number of varieties, systematically changes from one importer country to another in an international trade context. Then a natural question to ask is "What determines the Armington elasticity?" The answer comes from the distinction between the elasticity of demand with respect to the destination price (i.e., the Arm...

  5. Experimental determination of third-order elastic constants of diamond.

    Science.gov (United States)

    Lang, J M; Gupta, Y M

    2011-03-25

    To determine the nonlinear elastic response of diamond, single crystals were shock compressed along the [100], [110], and [111] orientations to 120 GPa peak elastic stresses. Particle velocity histories and elastic wave velocities were measured by using laser interferometry. The measured elastic wave profiles were used, in combination with published acoustic measurements, to determine the complete set of third-order elastic constants. These constants represent the first experimental determination, and several differ significantly from those calculated by using theoretical models.

  6. Vibration of an Elastic Circular Plate on an Elastic Half Space

    DEFF Research Database (Denmark)

    Krenk, Steen; Schmidt, H.

    1981-01-01

    The axisymmetric problem of a vibrating elastic plate on an elastic half space is solved by a direct method, in which the contact stresses and the normal displacements of the plate are taken as the unknown functions. First, the influence functions that give the displacements in terms...

  7. Asymmetric Vibrations of a Circular Elastic Plate on an Elastic Half Space

    DEFF Research Database (Denmark)

    Schmidt, H.; Krenk, Steen

    1982-01-01

    The asymmetric problem of a vibrating circular elastic plate in frictionless contact with an elastic half space is solved by an integral equation method, where the contact stress appears as the unknown function. By a trigonometric expansion, the problem is reduced to a number of uncoupled two...

  8. Elastic-plastic collapse of super-elastic shock waves in face-centered-cubic solids

    International Nuclear Information System (INIS)

    Zhakhovsky, Vasily V; Demaske, Brian J; Oleynik, Ivan I; Inogamov, Nail A; White, Carter T

    2014-01-01

    Shock waves in the [110] and [111] directions of single-crystal Al samples were studied using molecular dynamics (MD) simulations. Piston-driven simulations were performed to investigate the split shock-wave regime. At low piston velocities, the material is compressed initially to a metastable over-compressed elastic state leading to a super-elastic single shock wave. This metastable elastic state later collapses to a plastic state resulting in the formation of a two-wave structure consisting of an elastic precursor followed by a slower plastic wave. The single two-zone elastic-plastic shock-wave regime appearing at higher piston velocities was studied using moving window MD. The plastic wave attains the same average speed as the elastic precursor to form a single two-zone shock wave. In this case, repeated collapse of the highly over-compressed elastic state near the plastic shock front produces ultrashort triangle pulses that provide the pressure support for the leading elastic precursor.

  9. Is Contralateral Templating Reliable for Establishing Rotational Alignment During Intramedullary Stabilization of Femoral Shaft Fractures? A Study of Individual Bilateral Differences in Femoral Version.

    Science.gov (United States)

    Croom, William P; Lorenzana, Daniel J; Auran, Richard L; Cavallero, Matthew J; Heckmann, Nathanael; Lee, Jackson; White, Eric A

    2018-02-01

    To determine native individual bilateral differences (IBDs) in femoral version in a diverse population. Computed tomography scans with complete imaging of uninjured bilateral femora were used to determine femoral version and IBDs in version. Age, sex, and ethnicity of each subject were also collected. Femoral version and IBDs in version were correlated with demographic variables using univariate and multivariate regression models. One hundred sixty-four subjects were included in the study. The average femoral version was 9.4 degrees (±9.4 degrees). The mean IBD in femoral version was 5.4 degrees (±4.4 degrees, P alignment during intramedullary stabilization of diaphyseal femur fractures. This is also an important consideration when considering malrotation of femur fractures because most studies define malrotation as a greater than 10-15-degree difference compared with the contralateral side. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  10. 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.

  11. Freezing of Rat Tibiae at -20°C Does Not Affect the Mechanical Properties of Intramedullary Bone/Implant-Interface: Brief Report

    Science.gov (United States)

    Diefenbeck, Michael; Mückley, Thomas; Zankovych, Sergiy; Bossert, Jörg; Jandt, Klaus D; Schrader, Christian; Schmidt, Jürgen; Finger, Ulrich; Faucon, Mathilde

    2011-01-01

    Background: The effects of freezing-thawing cycles on intramedullary bone-implant interfaces have been studied in a rat model in mechanical pull-out tests. Implants: Twenty TiAl6V4 rods (Ø 0.8 mm, length 10 mm) implanted in rat tibiae Methods: 10 rats underwent bilateral tibial implantation of titanium rods. At eight weeks, the animals were sacrificed and tibiae harvested for biomechanical testing. Eight tibiae were frozen and stored at -20°C for 14 days, the remaining eight were evaluated immediately post-harvest. Pull-out tests were used to determine maximum force and interfacial shear strength. Results: There were no significant differences between fresh and those of the frozen-thawed group in maximum force or in interfacial shear strength. Conclusion: Frozen Storage of rat tibiae containing implants at -20° C has no effects on the biomechanical properties of Bone/ Implant interface. PMID:21760868

  12. Size effect of the elastic modulus of rectangular nanobeams: Surface elasticity effect

    International Nuclear Information System (INIS)

    Yao Hai-Yan; Fan Wen-Liang; Yun Guo-Hong

    2013-01-01

    The size-dependent elastic property of rectangular nanobeams (nanowires or nanoplates) induced by the surface elasticity effect is investigated by using a developed modified core-shell model. The effect of surface elasticity on the elastic modulus of nanobeams can be characterized by two surface related parameters, i.e., inhomogeneous degree constant and surface layer thickness. The analytical results show that the elastic modulus of the rectangular nanobeam exhibits a distinct size effect when its characteristic size reduces below 100 nm. It is also found that the theoretical results calculated by a modified core-shell model have more obvious advantages than those by other models (core-shell model and core-surface model) by comparing them with relevant experimental measurements and computational results, especially when the dimensions of nanostructures reduce to a few tens of nanometers. (condensed matter: structural, mechanical, and thermal properties)

  13. Conical Refraction of Elastic Waves by Anisotropic Metamaterials and Application for Parallel Translation of Elastic Waves.

    Science.gov (United States)

    Ahn, Young Kwan; Lee, Hyung Jin; Kim, Yoon Young

    2017-08-30

    Conical refraction, which is quite well-known in electromagnetic waves, has not been explored well in elastic waves due to the lack of proper natural elastic media. Here, we propose and design a unique anisotropic elastic metamaterial slab that realizes conical refraction for horizontally incident longitudinal or transverse waves; the single-mode wave is split into two oblique coupled longitudinal-shear waves. As an interesting application, we carried out an experiment of parallel translation of an incident elastic wave system through the anisotropic metamaterial slab. The parallel translation can be useful for ultrasonic non-destructive testing of a system hidden by obstacles. While the parallel translation resembles light refraction through a parallel plate without angle deviation between entry and exit beams, this wave behavior cannot be achieved without the engineered metamaterial because an elastic wave incident upon a dissimilar medium is always split at different refraction angles into two different modes, longitudinal and shear.

  14. Vascular elastic photoacoustic tomography in humans

    Science.gov (United States)

    Hai, Pengfei; Zhou, Yong; Liang, Jinyang; Li, Chiye; Wang, Lihong V.

    2016-03-01

    Quantification of vascular elasticity can help detect thrombosis and prevent life-threatening conditions such as acute myocardial infarction or stroke. Here, we propose vascular elastic photoacoustic tomography (VE-PAT) to measure vascular elasticity in humans. VE-PAT was developed by incorporating a linear-array-based photoacoustic computed tomography system with a customized compression stage. By measuring the deformation of blood vessels under uniaxial loading, VE-PAT was able to quantify the vascular compliance. We first demonstrated the feasibility of VE-PAT in blood vessel phantoms. In large vessel phantoms, VE-PAT detected a decrease in vascular compliance due to simulated thrombosis, which was validated by a standard compression test. In small blood vessel phantoms embedded 3 mm deep in gelatin, VE-PAT detected elasticity changes at depths that are difficult to image using other elasticity imaging techniques. We then applied VE-PAT to assess vascular compliance in a human subject and detected a decrease in vascular compliance when an occlusion occurred downstream from the measurement point, demonstrating the potential of VE-PAT in clinical applications such as detection of deep venous thrombosis.

  15. Probing hysteretic elasticity in weakly nonlinear materials

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paul A [Los Alamos National Laboratory; Haupert, Sylvain [UPMC UNIV PARIS; Renaud, Guillaume [UPMC UNIV PARIS; Riviere, Jacques [UPMC UNIV PARIS; Talmant, Maryline [UPMC UNIV PARIS; Laugier, Pascal [UPMC UNIV PARIS

    2010-12-07

    Our work is aimed at assessing the elastic and dissipative hysteretic nonlinear parameters' repeatability (precision) using several classes of materials with weak, intermediate and high nonlinear properties. In this contribution, we describe an optimized Nonlinear Resonant Ultrasound Spectroscopy (NRUS) measuring and data processing protocol applied to small samples. The protocol is used to eliminate the effects of environmental condition changes that take place during an experiment, and that may mask the intrinsic elastic nonlinearity. As an example, in our experiments, we identified external temperature fluctuation as a primary source of material resonance frequency and elastic modulus variation. A variation of 0.1 C produced a frequency variation of 0.01 %, which is similar to the expected nonlinear frequency shift for weakly nonlinear materials. In order to eliminate environmental effects, the variation in f{sub 0} (the elastically linear resonance frequency proportional to modulus) is fit with the appropriate function, and that function is used to correct the NRUS calculation of nonlinear parameters. With our correction procedure, we measured relative resonant frequency shifts of 10{sup -5} , which are below 10{sup -4}, often considered the limit to NRUS sensitivity under common experimental conditions. Our results show that the procedure is an alternative to the stringent control of temperature often applied. Applying the approach, we report nonlinear parameters for several materials, some with very small nonclassical nonlinearity. The approach has broad application to NRUS and other Nonlinear Elastic Wave Spectroscopy approaches.

  16. Elastic Moduli of Permanently Densified Silica Glasses

    Science.gov (United States)

    Deschamps, T.; Margueritat, J.; Martinet, C.; Mermet, A.; Champagnon, B.

    2014-01-01

    Modelling the mechanical response of silica glass is still challenging, due to the lack of knowledge concerning the elastic properties of intermediate states of densification. An extensive Brillouin Light Scattering study on permanently densified silica glasses after cold compression in diamond anvil cell has been carried out, in order to deduce the elastic properties of such glasses and to provide new insights concerning the densification process. From sound velocity measurements, we derive phenomenological laws linking the elastic moduli of silica glass as a function of its densification ratio. The found elastic moduli are in excellent agreement with the sparse data extracted from literature, and we show that they do not depend on the thermodynamic path taken during densification (room temperature or heating). We also demonstrate that the longitudinal sound velocity exhibits an anomalous behavior, displaying a minimum for a densification ratio of 5%, and highlight the fact that this anomaly has to be distinguished from the compressibility anomaly of a-SiO2 in the elastic domain. PMID:25431218

  17. Population and energy elasticity of tornado casualties

    Science.gov (United States)

    Fricker, Tyler; Elsner, James B.; Jagger, Thomas H.

    2017-04-01

    Tornadoes are capable of catastrophic destruction and mass casualties, but there are yet no estimates of how sensitive the number of casualties are to changes in the number of people in harm's way or to changes in tornado energy. Here the relationship between tornado casualties (deaths and injuries), population, and energy dissipation is quantified using the economic concept of "elasticity." Records of casualties from individual tornadoes over the period 2007-2015 are fit to a regression model. The coefficient on the population term (population elasticity) indicates that a doubling in population increases the casualty rate by 21% [(17, 24)%, 95% credible interval]. The coefficient on the energy term (energy elasticity) indicates that a doubling in energy dissipation leads to a 33% [(30, 35)%, 95% credible interval] increase in the casualty rate. The difference in elasticity values show that on average, changes in energy dissipation have been relatively more important in explaining tornado casualties than changes in population. Assuming no changes in warning effectiveness or mitigation efforts, these elasticity estimates can be used to project changes in casualties given the known population trends and possible trends in tornado activity.

  18. Femoral Medialization, Fixation Failures, and Functional Outcome in Trochanteric Hip Fractures Treated With Either a Sliding Hip Screw or an Intramedullary Nail From Within a Randomized Trial.

    Science.gov (United States)

    Bretherton, Christopher P; Parker, Martyn J

    2016-12-01

    The aim of this study was to determine if femoral medialization influences residual pain and mobility and to determine if fixation method or fracture pattern influences the tendency to medialize. This study used data from within a randomized controlled trial. Peterborough City Hospital, UK. Eight hundred forty-four patients presenting with a trochanteric hip fracture were randomized. Five hundred thirty-eight were available for 1-year follow-up. Fractures were classified according to OTA/AO classification as 31 A1, A2, and A3. Randomized to fixation with a Targon proximal femoral nail or sliding hip screw (SHS). Femoral medialization was calculated from follow-up x-rays at a minimum of 28 days post-fixation. Pain and mobility scores were assessed at 1 year by an independent blinded observer. Fixation failure and revision procedures were assessed at a minimum of 1 year from injury. Patients with >50% medialization had worse pain (P = 0.012) and mobility scores (P = 0.013) at 1 year. They also had more fracture healing complications (P = 0.021) and required more revision procedures (P = 0.014). Fractures treated with SHS were more likely to medialize >50% compared with intramedullary nail (P fractures were more likely to medialize, and A3 fractures were more likely to undergo >50% medialization (P fractures treated with SHS to undergo femoral medialization and correlates this with worse functional outcomes. It supports the use of intramedullary nails for A3 fractures, which have a significant tendency to medialize. Prognostic level II. See Instructions for Authors for a complete description of levels of evidence.

  19. Staged protocol for the treatment of chronic femoral shaft osteomyelitis with Ilizarov's technique followed by the use of intramedullary locked nail.

    Science.gov (United States)

    Chou, Po-Hsin; Lin, Hsi-Hsien; Su, Yu-Pin; Chiang, Chao-Ching; Chang, Ming-Chau; Chen, Chuan-Mu

    2017-06-01

    Infected nonunion of the femoral shaft is uncommon, and usually presents with challenging therapeutic and reconstructive problems. There are still controversies over treating infected nonunion of the femoral shaft. The purposes of this retrospective study were to review the treatment outcomes and describe a staged protocol for spontaneous wound healing. Six patients with chronic femoral shaft infected-nonunion from October 2002 to September 2010 were included in this retrospective study. Serial plain films and triple films of lower legs were performed to evaluate the alignment of the treated femoral shaft and bony union following our staged protocol of Ilizarov distraction osteogenesis and intramedullary nailing. An average bone defect of 7 cm was noted after staged osteotomy. Mean follow-up was 87.5 (range, 38-133) months. Union was achieved in all six patients, with an average external fixation time of 6.8 (range, 5-11) months. There was no reinfection. One complication of a 4-cm leg discrepancy was noted, with an initial shortening of 15 cm. The mean knee ranges of motion (ROM) before staged protocols and at final follow-up were 64.2±8.6 (range, 60-75)° and 53.3±9.3 (range, 40-65)°, respectively. The ROM at the knee joint statistically decreased following staged protocols. In the treatment of chronic femur osteomyelitis, the staged protocol of Ilizarov distraction osteogenesis followed by intramedullary nailing was safe and successful, and allowed for union, realignment, reorientation, and leg-length restoration. With regard to the soft tissue, this technique provides a unique type of reconstructive closure for infected wounds. It is suggested that the staged protocol is reliable in providing successful simultaneous reconstruction for bone and soft tissue defects without flap coverage. Copyright © 2017. Published by Elsevier Taiwan LLC.

  20. Utilization of the bicipital groove axis for confirming alignment of the humerus with transepicondylar and ulnar shaft axes during intramedullary nailing.

    Science.gov (United States)

    Meriç, Gökhan; Zeybek, Gülşah; Kıray, Amaç; Atik, Aziz; Budeyri, Aydın; Koşay, Can

    2015-01-01

    Intramedullary nailing is the preferred surgical treatment of humerus shaft fractures. The purpose of this study was to investigate the relationship between the bicipital groove and specific anatomical landmarks in achieving correct alignment of the humerus during intramedullary nailing, and to describe these anatomical landmarks. Thirty (15 right; 15 left) total upper cadaver extremities were used in this study. After the anatomical landmarks were identified and marked, humeral head axis, transepicondylar axis, ulnar shaft axis, bicipital groove axis, and angular measurements of these were obtained. The mean angle between the bicipital groove axis and transepicondylar axis was 48.17°±12.35º (range: 20.10º to 74.6º). The mean angle between the bicipital groove axis and ulna diaphysis axis was 41.82º±11.56 º (range: 17.91º to 68.27º). The mean angle between the humeral head axis and bicipital groove axis was 20.53°±3.90º (range: 11.85º to 31.81º). The mean retroversion angle between the humeral head axis and transepicondylar axis was 27.52±11.37º (range: 4.26º to 49.36º). The mean angle between the humeral head axis and ulna diaphysis axis was 61.73º±12.08º (range: 33.97º to 86.37º). The mean torsion angle was 62.58º±11.28 º (range: 40.74º to 85.74º). Measurement and utilization of the relationship between the bicipital groove, ulna diaphysis and transepicondylar axes may be used for restoring humeral rotation.