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Sample records for femoral tunnel length

  1. Drilling the femoral tunnel during ACL reconstruction: transtibial versus anteromedial portal techniques.

    Science.gov (United States)

    Tudisco, Cosimo; Bisicchia, Salvatore

    2012-08-01

    Incorrect bone tunnel position, particularly on the femoral side, is a frequent cause of failed anterior cruciate ligament reconstruction. Several studies have reported that drilling the femoral tunnel through the anteromedial portal allows a more anatomical placement on the lateral femoral condyle and higher knee stability than does transtibial reconstruction.In the current study, the femoral tunnel was drilled with transtibial (n=6) and anteromedial (n=6) portal techniques in 12 cadaveric knees. With appropriate landmarks inserted into bone tunnels, the direction and length of the tunnels were determined on anteroposterior and lateral radiographs. Knee stability was evaluated with a KT1000 arthrometer (MEDmetric Corporation, San Diego, California) and pivot shift test, comparing the pre- and postoperative values of both techniques. Finally, all knees were dissected to enhance vision of the insertion of the reconstructed ligament. The anteromedial portal technique led to better placement of the femoral tunnel in the coronal and sagittal planes, with higher knee stability according to the pivot shift test but not the KT1000 arthrometer. Anatomical and clinical results reported in the literature on transtibial and anteromedial portal techniques are controversial, but most of studies report better results with the anteromedial portal technique, especially regarding rotational stability. The current cadaveric study showed that the anteromedial portal technique provided better tunnel placement on the lateral femoral condyle in the coronal and sagittal planes, with an improvement in the rotational stability of the knee. Copyright 2012, SLACK Incorporated.

  2. Does flexible tunnel drilling affect the femoral tunnel angle measurement after anterior cruciate ligament reconstruction?

    NARCIS (Netherlands)

    Muller, Bart; Hofbauer, Marcus; Atte, Akere; van Dijk, C. Niek; Fu, Freddie H.

    2015-01-01

    To quantify the mean difference in femoral tunnel angle (FTA) as measured on knee radiographs between rigid and flexible tunnel drilling after anatomic anterior cruciate ligament (ACL) reconstruction. Fifty consecutive patients that underwent primary anatomic ACL reconstruction with a single femoral

  3. Contact area between femoral tunnel and interference screw in anatomic rectangular tunnel ACL reconstruction: a comparison of outside-in and trans-portal inside-out techniques.

    Science.gov (United States)

    Hiramatsu, Kunihiko; Mae, Tatsuo; Tachibana, Yuta; Nakagawa, Shigeto; Shino, Konsei

    2018-02-01

    The purpose of this study was to compare the femoral tunnel length, the femoral graft bending angle at the femoral tunnel aperture, and the contact area between the femoral tunnel wall and an interference screw used for fixation in anatomic rectangular tunnel anterior cruciate ligament (ACL) reconstruction (ART ACLR). The study included 149 patients with primary ACL injury who underwent ART ACLR. Preoperatively, flexion angle of the index knee was checked under general anaesthesia. Those of less than 130° of passive flexion were assigned to the outside-in (OI) technique (78 patients), while the others to the trans-portal inside-out (TP) technique (71 patients). The patients underwent computed tomography with multiplanar reconstruction at 3-5 weeks post-operatively. Femoral tunnel length, graft bending angle, and contact ratio between the IFS and femoral tunnel were assessed. P contact ratio in the OI technique was significantly larger than that in the TP technique at every point in the femoral tunnel (P contact ratio than the TP technique after ART ACLR. Retrospective comparative study, Level III.

  4. Does flexible tunnel drilling affect the femoral tunnel angle measurement after anterior cruciate ligament reconstruction?

    Science.gov (United States)

    Muller, Bart; Hofbauer, Marcus; Atte, Akere; van Dijk, C Niek; Fu, Freddie H

    2015-12-01

    To quantify the mean difference in femoral tunnel angle (FTA) as measured on knee radiographs between rigid and flexible tunnel drilling after anatomic anterior cruciate ligament (ACL) reconstruction. Fifty consecutive patients that underwent primary anatomic ACL reconstruction with a single femoral tunnel drilled with a flexible reamer were included in this study. The control group was comprised of 50 patients all of who underwent primary anatomic ACL reconstruction with a single femoral tunnel drilled with a rigid reamer. All femoral tunnels were drilled through a medial portal to ensure anatomic tunnel placement. The FTA was determined from post-operative anterior-to-posterior (AP) radiographs by two independent observers. A 5° difference between the two mean FTA was considered clinically significant. The average FTA, when drilled with a rigid reamer, was 42.0° ± 7.2°. Drilling with a flexible reamer resulted in a mean FTA of 44.7° ± 7.0°. The mean difference of 2.7° was not statistically significant. The intraclass correlation coefficient for inter-tester reliability was 0.895. The FTA can be reliably determined from post-operative AP radiographs and provides a useful and reproducible metric for characterizing femoral tunnel position after both rigid and flexible femoral tunnel drilling. This has implications for post-operative evaluation and preoperative treatment planning for ACL revision surgery. IV.

  5. Editorial Commentary: The All-Epiphyseal Anterior Cruciate Ligament Distal Femoral Approach: Sockets or Tunnels?

    Science.gov (United States)

    Cordasco, Frank A

    2018-05-01

    I believe that the distal femoral approach for anterior cruciate ligament reconstruction in the skeletally immature athlete with 3 to 6 years of remaining growth is best performed with an all-inside, all-epiphyseal technique using sockets rather than an outside-in approach creating tunnels. A shorter socket rather than a longer tunnel exposes a smaller surface area of the lateral distal femoral physis to potential compromise and resultant valgus malalignment. In addition, exiting the lateral femoral aspect of the epiphysis with a full-diameter tunnel as compared with a smaller diameter drill hole used to prepare a socket places the posterior articular cartilage, the lateral collateral ligament and anterolateral ligament footprints, and the popliteus tendon insertion at risk. My preference for sockets is also related to my belief that they provide a superior biologic milieu for graft incorporation compared with a full-length tunnel with the attendant violation of the lateral femoral cortex of the epiphysis. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. Accuracy of a computer-assisted planning and placement system for anatomical femoral tunnel positioning in anterior cruciate ligament reconstruction

    NARCIS (Netherlands)

    Luites, J.W.H.; Wymenga, A.B.; Blankevoort, L.; Eygendaal, D.; Verdonschot, Nicolaas Jacobus Joseph

    2014-01-01

    Background Femoral tunnel positioning is a difficult, but important factor in successful anterior cruciate ligament (ACL) reconstruction. Computer navigation can improve the anatomical planning procedure besides the tunnel placement procedure. Methods The accuracy of the computer-assisted femoral

  7. All-Epiphyseal Anterior Cruciate Ligament Femoral Tunnel Drilling: Avoiding Injury to the Physis, Lateral Collateral Ligament, Anterolateral Ligament, and Popliteus-A 3-Dimensional Computed Tomography Study.

    Science.gov (United States)

    Shea, Kevin G; Cannamela, Peter C; Fabricant, Peter D; Terhune, Elizabeth B; Polousky, John D; Milewski, Matthew D; Anderson, Allen F; Ganley, Theodore J

    2018-01-25

    To investigate the relation of the at-risk structures (distal femoral physis, lateral collateral ligament, anterolateral ligament, popliteus, and articular cartilage) during all-epiphyseal femoral tunnel drilling. A second purpose was 2-fold: (1) to develop recommendations for tunnel placement and orientation that anatomically reconstruct the anterior cruciate ligament (ACL) while minimizing the risk of injury to these at-risk structures, and (2) to allow for maximal tunnel length to increase the amount of graft in the socket to facilitate healing. Three-dimensional models of 6 skeletally immature knees (aged 7-11 years) were reconstructed from computed tomography and used to simulate all-epiphyseal femoral tunnels. Tunnels began within the ACL footprint and were directed laterally or anterolaterally, with the goal of avoiding injury to at-risk structures. The spatial relation between the ideal tunnel and these structures was evaluated. Full-length tunnels and partial length condyle sockets were simulated in the models using the same trajectories. An anterolateral tunnel could be placed to avoid direct injury to lateral structures. The safe zone on the anterolateral aspect of the femur was larger than that of a tunnel with a direct lateral trajectory (median 127 mm 2 vs 83 mm 2 , P = .028). Anterolateral tunnels were longer than direct lateral tunnels (median 30 mm vs 24 mm, P = .041). Safe angles for anterolateral tunnels were 34° to 40° from the posterior condylar axis; direct lateral tunnels were drilled 4° to 9° from the posterior condylar axis. Sockets could be placed without direct injury to structures at risk with either orientation. An all-epiphyseal ACL femoral tunnel can be placed without causing direct injury to at-risk structures. A tunnel angled anterolaterally from the ACL origin is longer and has a larger safe zone compared with the direct lateral tunnel. The largest safe zone for femoral all-epiphyseal ACL drilling was (1) anterior to

  8. 3D-Printed Patient-Specific ACL Femoral Tunnel Guide from MRI.

    Science.gov (United States)

    Rankin, Iain; Rehman, Haroon; Frame, Mark

    2018-01-01

    Traditional ACL reconstruction with non-anatomic techniques can demonstrate unsatisfactory long-term outcomes with regards instability and the degenerative knee changes observed with these results. Anatomic ACL reconstruction attempts to closely reproduce the patient's individual anatomic characteristics with the aim of restoring knee kinematics, in order to improve patient short and long-term outcomes. We designed an arthroscopic, patient-specific, ACL femoral tunnel guide to aid anatomical placement of the ACL graft within the femoral tunnel. The guide design was based on MRI scan of the subject's uninjured contralateral knee, identifying the femoral footprint and its anatomical position relative to the borders of the femoral articular cartilage. Image processing software was used to create a 3D computer aided design which was subsequently exported to a 3D-printing service. Transparent acrylic based photopolymer, PA220 plastic and 316L stainless steel patient-specific ACL femoral tunnel guides were created; the models produced were accurate with no statistical difference in size and positioning of the center of the ACL femoral footprint guide to MRI ( p =0.344, p =0.189, p =0.233 respectively). The guides aim to provide accurate marking of the starting point of the femoral tunnel in arthroscopic ACL reconstruction. This study serves as a proof of concept for the accurate creation of 3D-printed patient-specific guides for the anatomical placement of the femoral tunnel during ACL reconstruction.

  9. Factors that influence femoral neck length. Analysis of 1543 patients with advanced osteoarthritis of the hip

    NARCIS (Netherlands)

    Prins, Wybren; Kollen, Boudewijn J.; Ettema, Harmen B.; Verheyen, Cees C. P. M.

    2013-01-01

    Background and purpose: There is little known about the relationship between patient characteristic and the variance in geometrical properties of the femoral neck. The length of the femoral neck is relevant when considering a femoral neck preserving hip replacement. Based on surgical experience we

  10. Sonographic fetal weight estimation using femoral length: Honarvar Equation

    International Nuclear Information System (INIS)

    Firoozabadi, Raziah Dehghani; Ghasemi, N.; Firoozabadi, Mehdi Dehghani

    2007-01-01

    Fetal growth is the result of interactions between various factors and can be estimated by ultrasonic measurements. Fetal femur length is a scale for estimating the fetal weight in individual races because fetal growth patterns differ among different races. This was a prospective study involving 500 pregnant women at 36 weeks of gestational age. Real-time sonography was done to measure the femoral length and the weight of the fetus was estimated by the Honarvar 2 equation. The correlation between estimated fetal weight (EFW) and real weight was tested by Pearson correlation coefficient and relationships with the age and BMI of mother, the sex of the neonate and parity were tested by multiple regression. EFW by the Honarvar 2 equation correlated significantly with actual birthweight. Therefore, this equation is valid for fetal weight estimation. It also does not depend on the age and BMI of the mother, sex of the neonate, parity. Ethnicity potentially plays an important role in the fetal weight estimation. The Honarvar formula produced the best estimate of the actual birthweight for Iranian fetuses, and its use is recommended. (author)

  11. Influence of the different anteromedial portal on femoral tunnel orientation during anatomic ACL reconstruction

    Directory of Open Access Journals (Sweden)

    Dong-Kyu Moon

    2017-05-01

    Conclusions: In anatomic ACL reconstruction, a mal-positioned AM portal can cause abnormal tunnel orientation, which may lead to mechanical failure during ACL reconstruction. Therefore, it is important to select accurate AM portal positioning, and possibly using an AAM portal by measuring an accurate position when drilling a femoral tunnel in anatomic ACL reconstruction.

  12. Influence of knee flexion angle and transverse drill angle on creation of femoral tunnels in double-bundle anterior cruciate ligament reconstruction using the transportal technique: Three-dimensional computed tomography simulation analysis.

    Science.gov (United States)

    Choi, Chong Hyuk; Kim, Sung-Jae; Chun, Yong-Min; Kim, Sung-Hwan; Lee, Su-Keon; Eom, Nam-Kyu; Jung, Min

    2018-01-01

    The purpose of this study was to find appropriate flexion angle and transverse drill angle for optimal femoral tunnels of anteromedial (AM) bundle and posterolateral (PL) bundle in double-bundle ACL reconstruction using transportal technique. Thirty three-dimensional knee models were reconstructed. Knee flexion angles were altered from 100° to 130° at intervals of 10°. Maximum transverse drill angle (MTA), MTA minus 10° and 20° were set up. Twelve different tunnels were determined by four flexion angles and three transverse drill angles for each bundle. Tunnel length, wall breakage, inter-tunnel communication and graft-bending angle were assessed. Mean tunnel length of AM bundle was >30mm at 120° and 130° of flexion in all transverse drill angles. Mean tunnel length of PL bundle was >30mm during every condition. There were ≥1 cases of wall breakage except at 120° and 130° of flexion with MTA for AM bundle. There was no case of wall breakage for PL bundle. Considering inter-tunnel gap of >2mm without communication and obtuse graft-bending angle, 120° of flexion and MTA could be recommended as optimal condition for femoral tunnels of AM and PL bundles. Flexion angle and transverse drill angle had combined effect on femoral tunnel in double-bundle ACL reconstruction using transportal technique. Achieving flexion angle of 120° and transverse drill angle close to the medial femoral condyle could be recommended as optimal condition for femoral tunnels of AM and PL bundles to avoid insufficient tunnel length, wall breakage, inter-tunnel communication and acute graft-bending angle. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure

    International Nuclear Information System (INIS)

    Burton, Kirsteen R.; Guo, Lancia L. Q.; Tan, Kong T.; Simons, Martin E.; Sniderman, Kenneth W.; Kachura, John R.; Beecroft, John R.; Rajan, Dheeraj K.

    2012-01-01

    Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.

  14. Minimal Length Effects on Tunnelling from Spherically Symmetric Black Holes

    Directory of Open Access Journals (Sweden)

    Benrong Mu

    2015-01-01

    Full Text Available We investigate effects of the minimal length on quantum tunnelling from spherically symmetric black holes using the Hamilton-Jacobi method incorporating the minimal length. We first derive the deformed Hamilton-Jacobi equations for scalars and fermions, both of which have the same expressions. The minimal length correction to the Hawking temperature is found to depend on the black hole’s mass and the mass and angular momentum of emitted particles. Finally, we calculate a Schwarzschild black hole's luminosity and find the black hole evaporates to zero mass in infinite time.

  15. A comparison of locked versus nonlocked Enders rods for length unstable pediatric femoral shaft fractures.

    Science.gov (United States)

    Ellis, Henry Bone; Ho, Christine A; Podeszwa, David A; Wilson, Philip L

    2011-12-01

    Stainless steel flexible Enders rods have been used for intramedullary fixation of pediatric femur fractures with good success. Despite intraoperative anatomic alignment, length unstable femur fractures can present postoperatively with fracture shortening. The purpose of this study was to review all length unstable pediatric femoral shaft fractures in which Enders rods were used and compare those that were locked to those that were not locked. A retrospective clinical and radiographic review of all patients at a single institution undergoing flexible intramedullary fixation for length unstable femoral shaft fractures from 2001 to 2008. A length unstable fracture was defined as either a comminuted fracture or a spiral fracture longer than twice the diameter of the femoral shaft. A total of 107 length unstable femoral shaft fractures fixed with Enders rods were identified, of which 37 cases (35%) had both Enders rods "locked" through the eyelet in the distal femur with a 2.7 mm fully threaded cortical screw. Patient demographics, clinical course, complications, fracture characteristics, and radiographic outcomes were compared for the locked and nonlocked groups. There were no statistical differences between the groups in demographic data, operative variables, fracture pattern, fracture location, time to union, femoral alignment, or major complications. Shortening of the femur and nail migration measured at 1 to 6 weeks postoperatively was significantly greater for the nonlocked cases. The medial and lateral locked Enders rods moved 1.3 and 1.9 mm, respectively, and the unlocked Enders each moved 12.1 mm (P < 0.05). At final follow-up there were significantly more (P < 0.05) clinical complaints in nonlocked group, including limp, clinical shortening, and painful palpable rods. Locking Enders rods for length unstable pediatric fractures is an excellent option to prevent shortening and resulted in no additional complications, added surgical time, or increased blood loss

  16. Tibial and Femoral Tunnel Changes After ACL Reconstruction: A Prospective 2-Year Longitudinal MRI Study.

    Science.gov (United States)

    Weber, Alexander E; Delos, Demetris; Oltean, Hanna N; Vadasdi, Katherine; Cavanaugh, John; Potter, Hollis G; Rodeo, Scott A

    2015-05-01

    Tunnel widening after anterior cruciate ligament reconstruction (ACL-R) is a well-accepted and frequent phenomenon, yet little is known regarding its origin or natural history. To prospectively evaluate the cross-sectional area (CSA) changes in tibial and femoral bone tunnels after ACL-R with serial MRI. Case series; Level of evidence, 4. Patients underwent arthroscopic ACL-R with the same surgeon, surgical technique, and rehabilitation protocol. Each patient underwent preoperative dual-energy x-ray absorptiometry and clinical evaluation, as well as postoperative time zero MRI followed by subsequent MRI and clinical examination, including functional and subjective outcome tests, at 6, 12, 24, 52, and 104 weeks. Tibial and femoral tunnel CSA was measured on each MRI at tunnel aperture (ttA and ftA), midsection (ttM and ftM), and exit (ttE and ftE). Logistic regression modeling was used to examine the predictive value of demographic data and preoperative bone quality (as measured by dual-energy x-ray absorptiometry) on functional outcome scores, manual and instrumented laxity measurements, and changes in tunnel area over time. Eighteen patients (including 12 men), mean age 35.5±8.7 years, underwent ACL-R. There was significant tunnel expansion at ttA and ftA sites 6 weeks postoperatively (P=.024 and .0045, respectively). Expansion continued for 24 weeks, with progressive tunnel narrowing thereafter. Average ttA CSA was significantly larger than ftA CSA at all times. The ttM significantly expanded after 6 weeks (P=.06); continued expansion to week 12 was followed by 21 months of reduction in tunnel diameter. The ftM and both ttE and ftE sites decreased in CSA over the 2 years. Median Lysholm and International Knee Documentation Committee scores significantly improved at final follow-up (P=.0083 and 1 year from time of injury) predicted increased tunnel widening and accelerated expansion in CSA (Pclinical outcome. Younger age, male sex, and delay from injury to ACL

  17. Peak stresses shift from femoral tunnel aperture to tibial tunnel aperture in lateral tibial tunnel ACL reconstructions: a 3D graft-bending angle measurement and finite-element analysis.

    Science.gov (United States)

    Van Der Bracht, Hans; Tampere, Thomas; Beekman, Pieter; Schepens, Alexander; Devriendt, Wouter; Verdonk, Peter; Victor, Jan

    2018-02-01

    To investigate the effect of tibial tunnel orientation on graft-bending angle and stress distribution in the ACL graft. Eight cadaveric knees were scanned in extension, 45°, 90°, and full flexion. 3D reconstructions with anatomically placed anterior cruciate ligament (ACL) grafts were constructed with Mimics 14.12 ® . 3D graft-bending angles were measured for classic medial tibial tunnels (MTT) and lateral tibial tunnels (LTT) with different drill-guide angles (DGA) (45°, 55°, 65°, and 75°). A pivot shift was performed on 1 knee in a finite-element analysis. The peak stresses in the graft were calculated for eight different tibial tunnel orientations. In a classic anatomical ACL repair, the largest graft-bending angle and peak stresses are seen at the femoral tunnel aperture. The use of a different DGA at the tibial side does not change the graft-bending angle at the femoral side or magnitude of peak stresses significantly. When using LTT, the largest graft-bending angles and peak stresses are seen at the tibial tunnel aperture. In a classic anatomical ACL repair, peak stresses in the ACL graft are found at the femoral tunnel aperture. When an LTT is used, peak stresses are similar compared to classic ACL repairs, but the location of the peak stress will shift from the femoral tunnel aperture towards the tibial tunnel aperture. the risk of graft rupture is similar for both MTTs and LTTs, but the location of graft rupture changes from the femoral tunnel aperture towards the tibial tunnel aperture, respectively. I.

  18. Knee rotation influences the femoral tunnel angle measurement after anterior cruciate ligament reconstruction: a 3-dimensional computed tomography model study

    Science.gov (United States)

    Tang, Jing; Thorhauer, Eric; Marsh, Chelsea; Fu, Freddie H.

    2013-01-01

    Purpose Femoral tunnel angle (FTA) has been proposed as a metric for evaluating whether ACL reconstruction was performed anatomically. In clinic, radiographic images are typically acquired with an uncertain amount of internal/external knee rotation. The extent to which knee rotation will influence FTA measurement is unclear. Furthermore, differences in FTA measurement between the two common positions (0° and 45° knee flexion) have not been established. The purpose of this study was to investigate the influence of knee rotation on FTA measurement after ACL reconstruction. Methods Knee CT data from 16 subjects were segmented to produce 3D bone models. Central axes of tunnels were identified. The 0° and 45° flexion angles were simulated. Knee internal/external rotations were simulated in a range of ±20°. FTA was defined as the angle between the tunnel axis and femoral shaft axis, orthogonally projected into the coronal plane. Results Femoral tunnel angle was positively/negatively correlated with knee rotation angle at 0°/45° knee flexion. At 0° knee flexion, FTA for anterio-medial (AM) tunnels was significantly decreased at 20° of external knee rotation. At 45° knee flexion, more than 16° external or 19° internal rotation significantly altered FTA measurements for single-bundle tunnels; smaller rotations (±9° for AM, ±5° for PL) created significant errors in FTA measurements after double-bundle reconstruction. Conclusion Femoral tunnel angle measurements were correlated with knee rotation. Relatively small imaging malalignment introduced significant errors with knee flexed 45°. This study supports using the 0° flexion position for knee radiographs to reduce errors in FTA measurement due to knee internal/external rotation. Level of evidence Case–control study, Level III. PMID:23589127

  19. Transphyseal ACL Reconstruction in Skeletally Immature Patients: Does Independent Femoral Tunnel Drilling Place the Physis at Greater Risk Compared With Transtibial Drilling?

    Science.gov (United States)

    Cruz, Aristides I; Lakomkin, Nikita; Fabricant, Peter D; Lawrence, J Todd R

    2016-06-01

    Most studies examining the safety and efficacy of transphyseal anterior cruciate ligament (ACL) reconstruction for skeletally immature patients utilize transtibial drilling. Independent femoral tunnel drilling may impart a different pattern of distal femoral physeal involvement. To radiographically assess differences in distal femoral physeal disruption between transtibial and independent femoral tunnel drilling. We hypothesized that more oblique tunnels associated with independent drilling involve a significantly larger area of physeal disruption compared with vertically oriented tunnels. Cross-sectional study; Level of evidence, 3. We analyzed skeletally immature patients aged between 10 and 15 years who underwent transphyseal ACL reconstruction utilizing an independent femoral tunnel drilling technique between January 1, 2008, and March 31, 2011. These patients were matched with a transtibial technique cohort based on age and sex. Radiographic measurements were recorded from preoperative magnetic resonance imaging and postoperative radiographs. Ten patients in each group were analyzed. There were significant differences between independent drilling and transtibial drilling cohorts in the estimated area of physeal disruption (1.64 vs 0.74 cm(2); P drilling technique disrupt a larger area of the distal femoral physis and create more eccentric tunnels compared with a transtibial technique. As most studies noting the safety of transphyseal ACL reconstruction have utilized a central, vertical femoral tunnel, surgeons should be aware that if an independent femoral tunnel technique is utilized during transphyseal ACL reconstruction, more physeal tissue is at risk and tunnels are more eccentrically placed across the physis when drilling at more horizontal angles. Prior studies have shown that greater physeal involvement and eccentric tunnels may increase the risk of growth disturbance.

  20. Comparison of femoral tunnel widening between outside-in and trans-tibial double-bundle ACL reconstruction.

    Science.gov (United States)

    Lee, Yong Seuk; Lee, Beom Koo; Oh, Won Seok; Cho, Yong Kyun

    2014-09-01

    The objectives of this study were to compare (1) the degree of widening by comparing the diameter at the most widened area and the site of widening by measuring the distance from the tunnel entrance to the most widened area in two femoral tunnels (anteromedial and posterolateral), and (2) the morphologic change at the tunnel entrance between outside-in and trans-tibial double-bundle anterior cruciate ligament (ACL) reconstruction. A retrospective study that included 17 trans-tibial and 19 outside-in double-bundle ACL reconstructed patients was conducted for evaluation of serial computed tomography (CT) scan (immediate post-operation and post-operative 1 year). Digital image communication in medicine (DICOM) data was extracted from the PiViewSTAR and imported into OsiriX, which was installed on a Macbook Pro laptop computer. Diameter of the most widened area and distance from the entrance to this point were measured from each of two perpendicular (sagittal and coronal) planes that were accurately realigned parallel to the tunnel direction. Change in the morphology of the tunnel entrance between immediate post-operation and 1-year post-operation was evaluated. Widening was observed in both planes of both tunnels in the two techniques. However, no statistical significances in the diameter of most widened area and distance from the tunnel entrance to the most widened point were observed between the both techniques (n.s.). Distances from the centre point to each four sections showed an increase in all four sections of all both tunnels in both techniques. However, no statistical significance was observed between the two techniques (n.s.). Widening was observed in all tunnels using both techniques and degrees, and sites of the widening did not differ between groups. Morphologic change at the tunnel entrance was not limited to the specific direction and occurred in all directions without significant difference between groups. Retrospective comparative study, Level III.

  1. Post-operative 3D CT feedback improves accuracy and precision in the learning curve of anatomic ACL femoral tunnel placement.

    Science.gov (United States)

    Sirleo, Luigi; Innocenti, Massimo; Innocenti, Matteo; Civinini, Roberto; Carulli, Christian; Matassi, Fabrizio

    2018-02-01

    To evaluate the feedback from post-operative three-dimensional computed tomography (3D-CT) on femoral tunnel placement in the learning process, to obtain an anatomic anterior cruciate ligament (ACL) reconstruction. A series of 60 consecutive patients undergoing primary ACL reconstruction using autologous hamstrings single-bundle outside-in technique were prospectively included in the study. ACL reconstructions were performed by the same trainee-surgeon during his learning phase of anatomic ACL femoral tunnel placement. A CT scan with dedicated tunnel study was performed in all patients within 48 h after surgery. The data obtained from the CT scan were processed into a three-dimensional surface model, and a true medial view of the lateral femoral condyle was used for the femoral tunnel placement analysis. Two independent examiners analysed the tunnel placements. The centre of femoral tunnel was measured using a quadrant method as described by Bernard and Hertel. The coordinates measured were compared with anatomic coordinates values described in the literature [deep-to-shallow distance (X-axis) 28.5%; high-to-low distance (Y-axis) 35.2%]. Tunnel placement was evaluated in terms of accuracy and precision. After each ACL reconstruction, results were shown to the surgeon to receive an instant feedback in order to achieve accurate correction and improve tunnel placement for the next surgery. Complications and arthroscopic time were also recorded. Results were divided into three consecutive series (1, 2, 3) of 20 patients each. A trend to placing femoral tunnel slightly shallow in deep-to-shallow distance and slightly high in high-to-low distance was observed in the first and the second series. A progressive improvement in tunnel position was recorded from the first to second series and from the second to the third series. Both accuracy (+52.4%) and precision (+55.7%) increased from the first to the third series (p process to improve accuracy and precision of femoral

  2. Drifting Diaphyses: Asymmetry in Diametric Growth and Adaptation Along the Humeral and Femoral Length.

    Science.gov (United States)

    Maggiano, Isabel S; Maggiano, Corey M; Tiesler, Vera G; Chi-Keb, Julio R; Stout, Sam D

    2015-10-01

    This study quantifies regional histomorphological variation along the human humeral and femoral diaphysis in order to gain information on diaphyseal growth and modeling drift patterns. Three thin sections at 40, 50, and 60% bone length were prepared from a modern Mexican skeletal sample with known age and sex to give a longitudinal perspective on the drifting cortex (12 adults and juveniles total, 7 male and 5 female). Point-count techniques were applied across eight cross-sectional regions of interest using the starburst sampling pattern to quantify percent periosteal and endosteal primary lamellar bone at each diaphyseal level. The results of this study show a posterio-medial drift pattern in the humerus with a posterior rotational trend along the diaphysis. In the femur, we observed a consistent lateral to anteriolateral drift and an increase in primary lamellar bone area of both, periosteal and endosteal origin, towards the distal part of the diaphysis. These observations characterize drifting diaphyses in greater detail, raising important questions about how to resolve microscopic and macroscopic cross-sectional analysis towards a more complete understanding of bone growth and mechanical adaptation. Accounting for modeling drift has the potential to positively impact age and physical activity estimation, and explain some of the significant regional variation in bone histomorphology seen within (and between) bone cross-sections due to differing ages of tissue formation. More study is necessary, however, to discern between possible drift scenarios and characterize populational variation. © 2015 Wiley Periodicals, Inc.

  3. Reliability and reproducibility of several methods of arthroscopic assessment of femoral tunnel position during anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Ilahi, Omer A; Mansfield, David J; Urrea, Luis H; Qadeer, Ali A

    2014-10-01

    To assess interobserver and intraobserver agreement of estimating anterior cruciate ligament (ACL) femoral tunnel positioning arthroscopically using circular and linear (noncircular) estimation methods and to determine whether overlay template visual aids improve agreement. Standardized intraoperative pictures of femoral tunnel pilot holes (taken with a 30° arthroscope through an anterolateral portal at 90° of knee flexion with horizontal being parallel to the tibial surface) in 27 patients undergoing single-bundle ACL reconstruction were presented to 3 fellowship-trained arthroscopists on 2 separate occasions. On both viewings, each surgeon estimated the femoral tunnel pilot hole location to the nearest half-hour mark using a whole clock face and half clock face, to the nearest 15° using a whole compass and half compass, in the top or bottom half of a linear quadrant, and in the top or bottom half of a linear trisector. Evaluations were performed first without and then with an overlay template of each estimation method. The average difference among reviewers was quite similar for all 4 circular methods with the use of visual aids. Without overlay template visual aids, pair-wise κ statistic values for interobserver agreement ranged from -0.14 to 0.56 for the whole clock face and from 0.16 to 0.42 for the half clock face. With overlay visual guides, interobserver agreement ranged from 0.29 to 0.63 for the whole clock face and from 0.17 to 0.66 for the half clock face. The quadrant method's interobserver agreement ranged from 0.22 to 0.60, and that of the trisection method ranged from 0.17 to 0.57. Neither linear estimation method's reliability uniformly improved with the use of overlay templates. Intraobserver agreement without overlay templates ranged from 0.17 to 0.49 for the whole clock face, 0.11 to 0.47 for the half clock face, 0.01 to 0.66 for the quadrant method, and 0.20 to 0.57 for the trisection method. Use of overlay templates did not uniformly

  4. The relationship of lateral anatomic structures to exiting guide pins during femoral tunnel preparation utilizing an accessory medial portal.

    Science.gov (United States)

    Farrow, Lutul D; Parker, Richard D

    2010-06-01

    Anatomic reconstruction of the anterior cruciate ligament through an accessory medial portal has become increasingly popular. The purpose of this study is to describe the relationship of guide pin exit points to the lateral anatomic structures when preparing the anterior cruciate ligament femoral tunnel through an accessory medial portal. We utilized seven fresh frozen cadaveric knees. Utilizing an anteromedial approach, a guide wire was placed into the center of each bundle's footprint. Each guide wire was advanced through the lateral femoral cortex. The guide pins were passed at 90, 110, and 130 degrees of knee flexion. The distances from each guide pin to the closest relevant structures on the lateral side of the knee were measured. At 90 degrees the posterolateral bundle guide pin was closest to the lateral condyle articular cartilage (mean 5.4 +/- 2.2 mm) and gastrocnemius tendon (mean 5.7 +/- 2.1 mm). At 110 degrees the posterolateral bundle pin was closest to the gastrocnemius tendon (mean 4.5 +/- 3.4 mm). At 130 degrees the posterolateral bundle pin was closest to the gastrocnemius tendon (mean 7.2 +/- 5.5 mm) and lateral collateral ligament (mean 6.8 +/- 2.1 mm). At 90 degrees the anteromedial bundle guide pin was closest to the articular cartilage (mean 2.0 +/- 2.0 mm). At 110 degrees the anteromedial bundle pin was closest to the articular cartilage (mean 7.4 +/- 3.5 mm) and gastrocnemius tendon (mean 12.3 +/- 3.1 mm). At 130 degrees the AM bundle pin was closest to the gastrocnemius tendon (mean 8.2 +/- 3.2 mm) and LCL (mean 15.1 +/- 2.9 mm). Neither guide pin (anteromedial or posterolateral bundle) put the peroneal nerve at risk at any knee flexion angle. At low knee flexion angles the anteromedial and posterolateral bundle guide pins closely approximated multiple lateral structures when using an accessory medial arthroscopic portal. Utilizing higher flexion angles increases the margin of error when preparing both femoral tunnels. During preparation of

  5. Reducing the length of hospital stay after total knee arthroplasty: influence of femoral and sciatic nerve block.

    Science.gov (United States)

    Carvalho Júnior, Lúcio Honório de; Temponi, Eduardo Frois; Paganini, Vinícius Oliveira; Costa, Lincoln Paiva; Soares, Luiz Fernando Machado; Gonçalves, Matheus Braga Jacques

    2015-01-01

    the aim of this study is to evaluate the change in length of hospital stay postoperatively for Total Knee Arthroplasty after using femoral and sciatic nerve block. the medical records of 287 patients were evaluated, taking into account the number of hours of admission, the percentage and the reason for re-hospitalization within 30 days, as well as associated complications. All patients were divided into two groups according or not to whether they were admitted to ICU or not. During the years 2009 and 2010, isolated spinal anesthesia was the method used in the procedure. From 2011 on, femoral and sciatic nerve blocking was introduced. between the years 2009 and 2012, the average length of stay ranged from 74 hours in 2009 to 75.2 hours in 2010. The average length of stay in 2011 was 56.52 hours and 53.72 hours in 2012, all in the group of patients who did not remain in the ICU postoperatively. In the same period, among those in the group that needed ICU admission, the average length of stay was 138.7 hours in 2009, 90.25 hours in 2010, 79.8 hours in 2011, and 52.91 hours in 2012. During 2009 and 2010, the rate of re-hospitalization was 0%, while in 2011 and 2012, were 3.44% and 1%, respectively. according to this study, the use of femoral and sciatic nerve blocking after total knee arthroplasty allowed significant reduction in hospital stay.

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

    Directory of Open Access Journals (Sweden)

    Tahmasebi MN

    2011-05-01

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

  7. Double incision iso-anatomical ACL reconstruction: the freedom to place the femoral tunnel within the anatomical attachment site without exception.

    Science.gov (United States)

    Arnold, Markus P; Duthon, Victoria; Neyret, Philippe; Hirschmann, Michael T

    2013-02-01

    The present paper describes the rationale behind the surgical technique and the clinical results of the iso-anatomical, single bundle bone patellar-tendon bone anterior cruciate ligament (ACL) reconstruction. Using a second incision on the distal lateral femur an outside-in femoral tunnel is drilled. Guided by a special aiming device it is possible to place the femoral tunnel in the centre of the ACL footprint in every single case. Since every crucial step of the procedure is under visual control, the technique is safe and reliable, which is mirrored by good clinical results.

  8. Early integration of a bone plug in the femoral tunnel in rectangular tunnel ACL reconstruction with a bone-patellar tendon-bone graft: a prospective computed tomography analysis.

    Science.gov (United States)

    Suzuki, Tomoyuki; Shino, Konsei; Nakagawa, Shigeto; Nakata, Ken; Iwahashi, Takehiko; Kinugasa, Kazutaka; Otsubo, Hidenori; Yamashita, Toshihiko

    2011-12-01

    The purpose of this prospective study was to evaluate how early the bone plug was integrated into the rectangular femoral tunnel after anatomical ACL reconstruction using a bone-patellar tendon-bone (BTB) graft via a rectangular tunnel (RT BTB ACL-R). Twenty consecutive patients who had undergone the reconstruction procedure were evaluated by CT scans at 4 and 8 weeks postoperatively. In each scan, 30 slices for multiplanar reconstruction were collected parallel to the long axis of the parallelepiped femoral tunnel and perpendicular to the tendinous plane of the bone plug. Each slice was classified as "complete," indicating no visible gap between the plug and the tunnel wall or trabecular continuity or "incomplete," showing a visible gap. Bone plug-tunnel integration was evaluated as "excellent," "good," "fair," or "poor" for >20, 11-20, 5-10, and values at the anterior interface between the bone plug and the tunnel wall were also measured on both scans. The mean changes in CT value at 8 weeks were significantly lower than those at 4 weeks. This study shows that bone plug-femoral tunnel integration was almost complete by 8 weeks after surgery using RT BTB ACL-R.

  9. Reducing the length of hospital stay after total knee arthroplasty: influence of femoral and sciatic nerve block

    Directory of Open Access Journals (Sweden)

    Lúcio Honório de Carvalho Júnior

    2015-02-01

    Full Text Available Objective: the aim of this study is to evaluate the change in length of hospital stay postoperatively for Total Knee Arthroplasty after using femoral and sciatic nerve block. Materials and methods: the medical records of 287 patients were evaluated, taking into account the number of hours of admission, the percentage and the reason for re-hospitalization within 30 days, as well as associated complications. All patients were divided into two groups according or not to whether they were admitted to ICU or not. During the years 2009 and 2010, isolated spinal anesthesia was the method used in the procedure. From 2011 on, femoral and sciatic nerve blocking was introduced. Results: between the years 2009 and 2012, the average length of stay ranged from 74 hours in 2009 to 75.2 hours in 2010. The average length of stay in 2011 was 56.52 hours and 53.72 hours in 2012, all in the group of patients who did not remain in the ICU postoperatively. In the same period, among those in the group that needed ICU admission, the average length of stay was 138.7 hours in 2009, 90.25 hours in 2010, 79.8 hours in 2011, and 52.91 hours in 2012. During 2009 and 2010, the rate of re-hospitalization was 0%, while in 2011 and 2012, were 3.44% and 1%, respectively. Conclusion: according to this study, the use of femoral and sciatic nerve blocking after total knee arthroplasty allowed significant reduction in hospital stay.

  10. Advantages and Disadvantages of Transtibial, Anteromedial Portal, and Outside-In Femoral Tunnel Drilling in Single-Bundle Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    Science.gov (United States)

    Robin, Brett N; Jani, Sunil S; Marvil, Sean C; Reid, John B; Schillhammer, Carl K; Lubowitz, James H

    2015-07-01

    Controversy exists regarding the best method for creating the knee anterior cruciate ligament (ACL) femoral tunnel or socket. The purpose of this study was to systematically review the risks, benefits, advantages, and disadvantages of the endoscopic transtibial (TT) technique, anteromedial portal technique, outside-in technique, and outside-in retrograde drilling technique for creating the ACL femoral tunnel. A PubMed search of English-language studies published between January 1, 2000, and February 17, 2014, was performed using the following keywords: "anterior cruciate ligament" AND "femoral tunnel." Included were studies reporting risks, benefits, advantages, and/or disadvantages of any ACL femoral technique. In addition, references of included articles were reviewed to identify potential studies missed in the original search. A total of 27 articles were identified through the search. TT technique advantages include familiarity and proven long-term outcomes; disadvantages include the risk of nonanatomic placement because of constrained (TT) drilling. Anteromedial portal technique advantages include unconstrained anatomic placement; disadvantages include technical challenges, short tunnels or sockets, and posterior-wall blowout. Outside-in technique advantages include unconstrained anatomic placement; disadvantages include the need for 2 incisions. Retrograde drilling technique advantages include unconstrained anatomic placement, as well as all-epiphyseal drilling in skeletally immature patients; disadvantages include the need for fluoroscopy for all-epiphyseal drilling. There is no one, single, established "gold-standard" technique for creation of the ACL femoral socket. Four accepted techniques show diverse and subjective advantages, disadvantages, risks, and benefits. Level V, systematic review of Level II through V evidence. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  11. Transportal femoral drilling creates more horizontal ACL graft orientation compared to transtibial drilling: A 3D CT imaging study.

    Science.gov (United States)

    Clockaerts, S; Van Haver, A; Verhaegen, J; Vuylsteke, K; Leenders, T; Lagae, K C; Verdonk, P

    2016-06-01

    The principle of anatomic anterior cruciate ligament (ACL) reconstruction is to create a femoral and tibial tunnel that resembles the insertion of the native ACL. Anatomic reconstruction leads to a more horizontal graft orientation that provides more rotational stability. The aim of this study is to investigate the best method to achieve anatomical reconstruction of femoral insertion of the ACL and thus, a more horizontal orientation of the ACL. We compared tunnel position and orientation between transportal femoral drilling technique and transtibial technique. Thirty-two patients were included. Post-operative CT scans were obtained and femur, tibia and ACL tunnels were reconstructed. The position and orientation of tibial and femoral tunnels were quantified using the quadrant method, and femoral tunnel length, ellipticity and posterior wall breakage were assessed. We also investigated clinical outcome. Analyses show that transportal drilled femoral tunnels were situated significantly lower than transtibial drilled tunnels (p<0.0001), resulting in a significantly more horizontal oriented ACL in the transportal group in coronal (p<0.0001) and sagittal plane (p=0.01). No differences were observed in depth of femoral tunnel position (p=0.44). Femoral tunnel length was shorter in the transportal group (p=0.01) with a more ellipsoidal femoral aperture (p=0.01). There were no differences between both groups in tibial position. There were no differences in clinical outcome measure between the transportal and transtibial groups. This study indicates that transportal drilling of the femoral tunnel leads to a more horizontal graft orientation of the ACL, without differences in clinical outcome. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. An anatomical study of the proximal aspect of the medial femoral condyle to define the proximal-distal condylar length

    Directory of Open Access Journals (Sweden)

    Chia-Ming Chang

    2017-01-01

    Full Text Available Objective: Despite its possible role in knee arthroplasty, the proximal-distal condylar length (PDCL of the femur has never been reported in the literature. We conducted an anatomic study of the proximal aspect of the medial femoral condyle to propose a method for measuring the PDCL. Materials and Methods: Inspection of dried bone specimens was carried out to assure the most proximal condylar margin (MPCM as the eligible starting point to measure the PDCL. Simulation surgery was performed on seven pairs of cadaveric knees to verify the clinical application of measuring the PDCL after locating the MPCM. Interobserver reliability of this procedure was also analyzed. Results: Observation of the bone specimens showed that the MPCM is a concavity formed by the junction of the distal end of the supracondylar ridge and the proximal margin of the medial condyle. This anatomically distinctive structure made the MPCM an unambiguous landmark. The cadaveric simulation surgical dissection demonstrated that the MPCM is easily accessed in a surgical setting, making the measurement of the PDCL plausible. The intraclass correlation coefficient was 0.78, indicating good interobserver reliability for this technique. Conclusion: This study has suggested that the PDCL can be measured based on the MPCM in a surgical setting. PDCL measurement might be useful in joint line position management, selection of femoral component sizes, and other applications related to the proximal-distal dimension of the knee. Further investigation is required.

  13. Development of a scanning tunneling potentiometry system for measurement of electronic transport at short length scales

    Science.gov (United States)

    Rozler, Michael

    It is clear that complete understanding of macroscopic properties of materials is impossible without a thorough knowledge of behavior at the smallest length scales. While the past 25 years have witnessed major advances in a variety of techniques that probe the nanoscale properties of matter, electrical transport measurements -- the heart of condensed matter research -- have lagged behind, never progressing beyond bulk measurements. This thesis describes a scanning tunneling potentiometry (STP) system developed to simultaneously map the transport-related electrochemical potential distribution of a biased sample along with its surface topography, extending electronic transport measurements to the nanoscale. Combining a novel sample biasing technique with a continuous current-nulling feedback scheme pushes the noise performance of the measurement to its fundamental limit - the Johnson noise of the STM tunnel junction. The resulting 130 nV voltage sensitivity allows us to spatially resolve local potentials at scales down to 2 nm, while maintaining atomic scale STM imaging, all at scan sizes of up to 15 microns. A mm-range two-dimensional coarse positioning stage and the ability to operate from liquid helium to room temperature with a fast turn-around time greatly expand the versatility of the instrument. Use of carefully selected model materials, combined with excellent topographic and voltage resolution has allowed us to distinguish measurement artifacts caused by surface roughness from true potentiometric features, a major problem in previous STP measurements. The measurements demonstrate that STP can produce physically meaningful results for homogeneous transport as well as non-uniform conduction dominated by material microstructures. Measurements of several physically interesting materials systems are presented as well, revealing new behaviors at the smallest length sales. The results establish scanning tunneling potentiometry as a useful tool for physics and

  14. 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.

  15. Engineering of multi-segmented light tunnel and flattop focus with designed axial lengths and gaps

    Science.gov (United States)

    Yu, Yanzhong; Huang, Han; Zhou, Mianmian; Zhan, Qiwen

    2018-01-01

    Based on the radiation pattern from a sectional-uniform line source antenna, a three-dimensional (3D) focus engineering technique for the creation of multi-segmented light tunnel and flattop focus with designed axial lengths and gaps is proposed. Under a 4Pi focusing system, the fields radiated from sectional-uniform magnetic and electromagnetic current line source antennas are employed to generate multi-segmented optical tube and flattop focus, respectively. Numerical results demonstrate that the produced light tube and flattop focus remain homogeneous along the optical axis; and their lengths of the nth segment and the nth gap between consecutive segments can be easily adjusted and only depend on the sizes of the nth section and the nth blanking between adjacent sectional antennas. The optical tube is a pure azimuthally polarized field but for the flattop focus the longitudinal polarization is dominant on the optical axis. To obtain the required pupil plane illumination for constructing the above focal field with prescribed characteristics, the inverse problem of the antenna radiation field is solved. These peculiar focusing fields might find potential applications in multi-particle acceleration, multi-particle trapping and manipulation.

  16. Effects of statistical distribution of joint trace length on the stability of tunnel excavated in jointed rock mass

    Directory of Open Access Journals (Sweden)

    Kayvan Ghorbani

    2015-12-01

    Full Text Available The rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. The performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. During underground excavation, many surrounding rock failures have close relationship with joints. The stability study on tunnel in jointed rock mass is of importance to rock engineering, especially tunneling and underground space development. In this study, using the probability density distribution functions of negative exponential, log-normal and normal, we investigated the effect of joint trace length on the stability parameters such as stress and displacement of tunnel constructed in rock mass using UDEC (Universal Distinct Element Code. It was obtained that normal distribution function of joint trace length is more critical on the stability of tunnel, and exponential distribution function has less effect on the tunnel stability compared to the two other distribution functions.

  17. Influence of slab length on dynamic characteristics of subway train-steel spring floating slab track-tunnel coupled system

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    Qing-yuan Xu

    Full Text Available A subway train-steel spring floating slab track-tunnel coupling dynamic model, considering short and middle-long wavelength random track irregularities, and longitudinal connection between adjacent slabs of steel spring floating slab track, was developed. And the influence of slab length on dynamic characteristics of the system under different track conditions and train speeds are theoretically studied. The calculated results show: (1 In general, the acceleration of each component of the coupled system decreases with the increase of slab length under the perfectly smooth track condition; (2 Slab length has different influence laws on acceleration of each component of subway train-steel spring floating slab track-tunnel coupled system under random irregularity of track condition. The lower the dominant frequency distribution of vibration acceleration is, the higher influence slab length has; (3 With the increase of slab length, the force of rail, fastener and steel spring also decreases significantly, which helps to lengthen the service life of these components; (4 With the increase of slab length, the longitudinal bending moment of slab increases sharply at first, then it begins to drop slightly. When slab length exceeds the distance between two bogies of a vehicle, the longitudinal bending moment of slab changes little; (5 Slab length has significant influence on the dynamic force and displacement of the coupled system when train speed is higher.

  18. Positioning of the femoral tunnel for arthroscopic reconstruction of the anterior cruciate ligament: comparative study of 2 techniques Posicionamento do túnel femoral na reconstrução artroscópica do LCA: estudo comparativo de duas técnicas

    Directory of Open Access Journals (Sweden)

    Roberto Freire da Mota Albuquerque

    2007-01-01

    Full Text Available OBJECTIVE: To compare the accuracy of positioning of the femoral tunnel in reconstructing the anterior cruciate ligament by means of 2 techniques: tibial tunnel and anteromedial portal. METHOD: Femoral tunnels were drilled in 20 knees from human cadavers by means of arthroscopy. Group I had the femoral tunnel drilled via a trans-tibial tunnel, and Group II via the anteromedial portal. Four variables were measured: A posterior wall thickness; B tunnel positioning at the notch; C tunnel inclination in relation to the femoral axis; and D distance between the wire guide exit and the lateral epicondyle. RESULTS: As above, respectively, A 2.23 mm for group I and 2.36 mm for group II (P =.54; B 25.5° for group I and 30.0° for group II (P =.23; C 23.9° for group I and 32.0° for group II (P =.02; D 7.8 cm for group I and 3.9 cm for group II (P OBJETIVO: Comparar a acurácia do posicionamento do túnel femoral na reconstrução do ligamento cruzado anterior através de duas vias: túnel tibial e portal ântero - medial. MÉTODO: Foram perfurados túneis femorais em vinte joelhos de cadáveres humanos por via artroscópica. Grupo I: túnel femoral por acesso trans túnel tibial. Grupo II: via portal ântero-medial. Quatro variáveis foram estudadas: A espessura da parede posterior; B posicionamento do túnel no intercôndilo; C angulação do túnel em relação ao eixo do fêmur; D distância entre a saída do fio guia e o epicôndilo lateral. RESULTADO: A grupo I: 2,23 mm, grupo II: 2,36 mm (p=0,543; B grupo I: 25,5º, grupo II: 30º (p=0,226; C grupo I: 23,9º, grupo II: 32º (p= 0,014; D grupo I: 7,8 cm, grupo II 3,9 cm (p<0,001. CONCLUSÃO: As duas técnicas obteveram o posicionamento desejado da entrada do túnel femoral e espessura adequada da cortical posterior. A perfuração via portal ântero-medial pode propiciar maior proteção contra rotura da parede posterior.

  19. Disadvantages and advantages of transtibial technique for creating the anterior cruciate ligament femoral socket.

    Science.gov (United States)

    Robin, Brett N; Lubowitz, James H

    2014-10-01

    Anterior cruciate ligament (ACL) femoral socket techniques have distinct advantages and disadvantages when considering the following techniques: transtibial, anteromedial portal, outside-in, and outside-in retroconstruction. There is no one perfect technique and we have an incomplete understanding of anatomical, biomechanical, isometry, stability, and clinical outcomes. Our primary focus is transtibial technique for creating the ACL femoral socket. Advantages include less invasive, isometric graft placement, stable Lachman exam, and minimal graft impingement with the tunnel and notch. Disadvantages include nonanatomic vertical graft placement that can cause rotational instability and positive pivot shift, interference screw divergence, graft-tunnel length mismatch, femoral socket constraint, posterior cruciate ligament impingement, and a short, oblique tibial tunnel that may undermine the medial plateau in an attempt to achieve anatomic ACL reconstruction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. Posterior Femoral Single Limb Osteotomy for the Removal of Well-Fixed Modular Femoral Neck Components

    Directory of Open Access Journals (Sweden)

    Keith A Fehring

    2017-07-01

    Full Text Available Modular neck femoral components were introduced to optimize femoral neck anteversion, leg length, offset, and stability in total hip arthroplasty. However, concerns have been raised in recent years regarding early failure of these implants due to corrosion, pseudotumor, as well as fracture of the modular neck. Removing modular neck femoral implants is challenging as removal of the modular femoral neck leaves a proximally coated femoral stem level with the proximal bone of the femoral neck. We describe a posterior femoral single limb osteotomy  (posterior cut of an extended trochanteric osteotomy for the removal of a modular neck femoral component.

  1. Femoral shaft fractures

    International Nuclear Information System (INIS)

    Bender, C.E.; Campbell, D.C. II

    1985-01-01

    The femur is the longest, largest, and strongest bone in the body. Because of its length, width, and role as primary weight-bearing bone, it must tolerate the extremes of axial loading and angulatory stresses. Massive musculature envelopes the femur. This masculature provides abundant blood supply to the bone, which also allows great potential for healing. Thus, the most significant problem relating to femoral shaft fractures is not healing, but restoration of bone length and alignment so that the femoral shaft will tolerate the functional stresses demanded of it

  2. Development and Validation of a Path Length Calculation for Carotid-Femoral Pulse Wave Velocity Measurement: A TASCFORCE, SUMMIT, and Caerphilly Collaborative Venture.

    Science.gov (United States)

    Weir-McCall, Jonathan R; Brown, Liam; Summersgill, Jennifer; Talarczyk, Piotr; Bonnici-Mallia, Michael; Chin, Sook C; Khan, Faisel; Struthers, Allan D; Sullivan, Frank; Colhoun, Helen M; Shore, Angela C; Aizawa, Kunihiko; Groop, Leif; Nilsson, Jan; Cockcroft, John R; McEniery, Carmel M; Wilkinson, Ian B; Ben-Shlomo, Yoav; Houston, J Graeme

    2018-05-01

    Current distance measurement techniques for pulse wave velocity (PWV) calculation are susceptible to intercenter variability. The aim of this study was to derive and validate a formula for this distance measurement. Based on carotid femoral distance in 1183 whole-body magnetic resonance angiograms, a formula was derived for calculating distance. This was compared with distance measurements in 128 whole-body magnetic resonance angiograms from a second study. The effects of recalculation of PWV using the new formula on association with risk factors, disease discrimination, and prediction of major adverse cardiovascular events were examined within 1242 participants from the multicenter SUMMIT study (Surrogate Markers of Micro- and Macrovascular Hard End-Points for Innovative Diabetes Tools) and 825 participants from the Caerphilly Prospective Study. The distance formula yielded a mean error of 7.8 mm (limits of agreement =-41.1 to 56.7 mm; P measurement, the distance formula did not change associations between PWV and age, blood pressure, or creatinine ( P accounting for differences in age, sex, and mean arterial pressure, intercenter differences in PWV persisted using the external distance measurement ( F =4.6; P =0.004), whereas there was a loss of between center difference using the distance formula ( F =1.4; P =0.24). PWV odds ratios for cardiovascular mortality remained the same using both the external distance measurement (1.14; 95% confidence interval, 1.06-1.24; P =0.001) and the distance formula (1.17; 95% confidence interval, 1.08-1.28; P measurement variability without impacting the diagnostic utility of carotid-femoral PWV. © 2018 The Authors.

  3. Variability in ACL tunnel placement: observational clinical study of surgeon ACL tunnel variability.

    Science.gov (United States)

    Wolf, Brian R; Ramme, Austin J; Wright, Rick W; Brophy, Robert H; McCarty, Eric C; Vidal, Armando R; Parker, Richard D; Andrish, Jack T; Amendola, Annunziato

    2013-06-01

    Multicenter and multisurgeon cohort studies on anterior cruciate ligament (ACL) reconstruction are becoming more common. Minimal information exists on intersurgeon and intrasurgeon variability in ACL tunnel placement. Purpose/ The purpose of this study was to analyze intersurgeon and intrasurgeon variability in ACL tunnel placement in a series of The Multicenter Orthopaedic Outcomes Network (MOON) ACL reconstruction patients and in a clinical cohort of ACL reconstruction patients. The hypothesis was that there would be minimal variability between surgeons in ACL tunnel placement. Cross-sectional study; Level of evidence, 3. Seventy-eight patients who underwent ACL reconstruction by 8 surgeons had postoperative imaging with computed tomography, and ACL tunnel location and angulation were analyzed using 3-dimensional surface processing and measurement. Intersurgeon and intrasurgeon variability in ACL tunnel placement was analyzed. For intersurgeon variability, the range in mean ACL femoral tunnel depth between surgeons was 22%. For femoral tunnel height, there was a 19% range. Tibial tunnel location from anterior to posterior on the plateau had a 16% range in mean results. There was only a small range of 4% for mean tibial tunnel location from the medial to lateral dimension. For intrasurgeon variability, femoral tunnel depth demonstrated the largest ranges, and tibial tunnel location from medial to lateral on the plateau demonstrated the least variability. Overall, surgeons were relatively consistent within their own cases. Using applied measurement criteria, 85% of femoral tunnels and 90% of tibial tunnels fell within applied literature-based guidelines. Ninety-one percent of the axes of the femoral tunnels fell within the boundaries of the femoral footprint. The data demonstrate that surgeons performing ACL reconstructions are relatively consistent between each other. There is, however, variability of average tunnel placement up to 22% of mean condylar depth

  4. Femoral nerve damage (image)

    Science.gov (United States)

    The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

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

    Directory of Open Access Journals (Sweden)

    Herrera Antonio

    2010-06-01

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

  6. Morphometric analysis of rat femoral vessels under a video magnification system

    Directory of Open Access Journals (Sweden)

    Rui Sergio Monteiro de Barros

    Full Text Available Abstract The right femoral vessels of 80 rats were identified and dissected. External lengths and diameters of femoral arteries and femoral veins were measured using either a microscope or a video magnification system. Findings were correlated to animals’ weights. Mean length was 14.33 mm for both femoral arteries and femoral veins, mean diameter of arteries was 0.65 mm and diameter of veins was 0.81 mm. In our sample, rats’ body weights were only correlated with the diameter of their femoral veins.

  7. Comparison of femoral morphology and bone mineral density between femoral neck fractures and trochanteric fractures.

    Science.gov (United States)

    Maeda, Yuki; Sugano, Nobuhiko; Saito, Masanobu; Yonenobu, Kazuo

    2011-03-01

    Many studies that analyzed bone mineral density (BMD) and skeletal factors of hip fractures were based on uncalibrated radiographs or dual-energy xray absorptiometry (DXA). Spatial accuracy in measuring BMD and morphologic features of the femur with DXA is limited. This study investigated differences in BMD and morphologic features of the femur between two types of hip fractures using quantitative computed tomography (QCT). Forty patients with hip fractures with normal contralateral hips were selected for this study between 2003 and 2007 (trochanteric fracture, n=18; femoral neck fracture, n=22). Each patient underwent QCT of the bilateral femora using a calibration phantom. Using images of the intact contralateral femur, BMD measurements were made at the point of minimum femoral-neck cross-sectional area, middle of the intertrochanteric region, and center of the femoral head. QCT images also were used to measure morphologic features of the hip, including hip axis length, femoral neck axis length, neck-shaft angle, neck width, head offset, anteversion of the femoral neck, and cortical index at the femoral isthmus. No significant differences were found in trabecular BMD between groups in those three regions. Patients with trochanteric fractures showed a smaller neck shaft angle and smaller cortical index at the femoral canal isthmus compared with patients with femoral neck fractures. We conclude that severe osteoporosis with thinner cortical bone of the femoral diaphysis is seen more often in patients with trochanteric fracture than in patients with femoral neck fracture. Level IV, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

  8. [Femoral arteriovenous fistula: a late uncommon complication of central venous catheterization].

    Science.gov (United States)

    Conz, P A; Malagoli, A; Normanno, M; Munaro, D

    2007-01-01

    A 77-year-old woman was admitted due to AV graft thrombosis; given the technical impossibility of performing other native AV fistulas, we chose to insert a tunnelled central venous catheter. Considering the vascular history of the patient, the central venous catheter could not be placed into the internal jugular vein; it was therefore put into the left femoral vein. Following a 3-month-period of the catheter working properly, the patient was hospitalized due to sudden acute pain in the left thigh. In a few days the patient developed an important haematoma with serious anemization in the left lower limb. Ultrasonography showed the presence of a fistula between the left common femoral artery and the femoral vein, leading to the subsequent successful positioning of a stent into the common femoral artery through right trans-femoral access. Angiography examination showed the femoral vein patency along the proximal stretch with respect to the function of the tunnelled venous catheter.

  9. Charge Islands Through Tunneling

    Science.gov (United States)

    Robinson, Daryl C.

    2002-01-01

    It has been recently reported that the electrical charge in a semiconductive carbon nanotube is not evenly distributed, but rather it is divided into charge "islands." This paper links the aforementioned phenomenon to tunneling and provides further insight into the higher rate of tunneling processes, which makes tunneling devices attractive. This paper also provides a basis for calculating the charge profile over the length of the tube so that nanoscale devices' conductive properties may be fully exploited.

  10. Computer-assisted anatomical placement of a double-bundle ACL through 3D-fitting of a statistically generated femoral template into individual knee geometry

    NARCIS (Netherlands)

    Luites, J. W. H.; Wymenga, A. B.; Sati, M.; Bourquin, Y.; Blankevoort, L.; van der Venne, R.; Kooloos, J. G. M.; Staubli, H. U.

    2000-01-01

    Femoral graft placement is an important factor in the success of ACL-reconstruction. Besides improving the accuracy of femoral tunnel placement, Computer Assisted Surgery (CAS) can be used to determine the anatomical Location. This requires a 3D femoral template with the position of the anatomical

  11. Three-Dimensional Analysis of the Characteristics of the Femoral Canal Isthmus: An Anatomical Study

    Directory of Open Access Journals (Sweden)

    Xiu-yun Su

    2015-01-01

    Full Text Available Purpose. To establish a new approach for measuring and locating the femoral intramedullary canal isthmus in 3-dimensional (3D space. Methods. Based on the computed tomography data from 204 Chinese patients, 3D models of the whole femur and the corresponding femoral isthmus tube were reconstructed using Mimics software (Materialise, Haasrode, Belgium. The anatomical parameters of the femur and the isthmus, including the femur length and radius, and the isthmus diameter and height, were measured accordingly. Results. The mean ratio of the isthmus height versus the femoral height was 55 ± 4.8%. The mean diameter of the isthmus was 10.49 ± 1.52 mm. The femoral length, the isthmus diameter, and the isthmus tube length were significantly larger in the male group. Significant correlations were observed between the femoral length and the isthmus diameter (r=0.24, p<0.01 and between the femoral length and the isthmus height (r=0.6, p<0.01. Stepwise linear regression analyses demonstrated that the femoral length and radius were the most important factors influencing the location and dimension of the femoral canal isthmus. Conclusion. The current study developed a new approach for measuring the femoral canal and for optimization of customer-specific femoral implants.

  12. Femoral head avascular necrosis

    International Nuclear Information System (INIS)

    Chrysikopoulos, H.; Sartoris, D.J.; Resnick, D.L.; Ashburn, W.; Pretorius, T.

    1988-01-01

    MR imaging has been shown to be more sensitive and specific than planar scintigraphy for avascular necrosis (AVN) of the femoral head. However, experience with single photon emission CT (SPECT) is limited. The authors retrospectively compared 1.5-T MR imaging with SPECT in 14 patients with suspected femoral head AVN. Agreement between MR imaging and SPECT was present in 24 femurs, 14 normal and ten with AVN. MR imaging showed changes of AVN in the remaining four femoral heads. Of these, one was normal and the other three inconclusive for AVN by SPECT. The authors conclude that MR imaging is superior to SPECT for the evaluation of AVN of the hip

  13. Radiographic anatomy of the proximal femur: femoral neck fracture vs. transtrochanteric fracture

    Directory of Open Access Journals (Sweden)

    Ana Lecia Carneiro Leão de Araújo Lima

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the correlation between radiographic parameters of the proximal femur with femoral neck fractures or transtrochanteric fractures. METHODS: Cervicodiaphyseal angle (CDA, femoral neck width (FNW, hip axis length (HAL, and acetabular tear drop distance (ATD were analyzed in 30 pelvis anteroposterior view X-rays of patients with femoral neck fractures (n = 15 and transtrochanteric fractures (n = 15. The analysis was performed by comparing the results of the X-rays with femoral neck fractures and with transtrochanteric fractures. RESULTS: No statistically significant differences between samples were observed. CONCLUSION: There was no correlation between radiographic parameters evaluated and specific occurrence of femoral neck fractures or transtrochanteric fractures.

  14. Femoral Condyle Fracture during Anterior Cruciate Ligament Reconstruction

    Directory of Open Access Journals (Sweden)

    Selahattin Ozyurek

    2015-07-01

    Full Text Available Dear Editor,We have greatly enjoyed reading the case report entitled “‘Femoral Condyle Fracture during Revision of Anterior Cruciate Ligament Reconstruction: Case Report and a Review of Literature in the issue of Arch Bone Jt Surg. 2015;3(2 with great interest. We would like to commend the authors for their detailed and valuable work. Although various case reports have described postoperative distal femur fracture at a range of time intervals (1,2 intraoperative intra-articular distal femur fracture is a unique entity.However, we believe that some important additional observations seem necessary to be contributed through this study. In this article, the authors stated that, to the best of their knowledge, there is no other case report in the literature introducing a femoral condyle fracture during arthroscopic ACL reconstruction or revision reconstruction. Nevertheless, we would like to call the attention of the readers to the fact that that the literature contains one additional case report re‌porting on intraoperative distal femoral coronal plane (Hoffa fracture during primary ACL reconstruction (2. Werner BC and Miller MD presented of case report of an intraoperative distal femoral coronal plane (Hoffa fracture that occurred during independent femoral tunnel drilling and dilation in a primary ACL reconstruction. As in the their case, this type of fracture can occur with appropriately placed femoral tunnels, but the risk can increase with larger graft diameters in patients with smaller lateral femoral condyles The patient was treated with open reduction and internal fixation, without compromise of graft stability and with good recovery of function. We believe that tailoring graft size to the size of the patient is important to prevent similar adverse events.

  15. Aneurysm of the superficial femoral artery in an infant

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, M.; Komuro, H.; Matoba, K.; Kaneko, M. [Dept. of Paediatric Surgery, Inst. of Clinical Medicine, Univ. of Tsukuba, Ibaraki (Japan); Niitsu, M.; Itai, Y. [Dept. of Radiology, Inst. of Clinical Medicine, Univ. of Tsukuba, Ibaraki (Japan)

    2003-04-01

    An isolated arterial aneurysm in childhood is extremely rare. We report a 1-year-old girl with an aneurysm of the right superficial femoral artery, presenting as an asymptomatic mass of the thigh. The aneurysm involved the whole superficial femoral artery (9 cm in length), and surgical treatment would have required replacement of the affected artery. Conservative treatment was chosen, influenced by the patient's rapid growth at that time. Non-invasive, 3-D contrast-enhanced magnetic resonance angiography (MRA) was useful as an alternative to conventional angiography for detailed evaluation of the femoral arteries, including the aneurysm. (orig.)

  16. Germanene nanoribbon tunneling field effect transistor (GeNR-TFET) with a 10 nm channel length: analog performance, doping and temperature effects

    International Nuclear Information System (INIS)

    Bayani, Amir Hossein; Vali, Mehran; Dideban, Daryoosh; Moezi, Negin

    2016-01-01

    In this paper, a scheme of the germanene nanoribbon tunneling field effect transistor (GeNR-TFET) is proposed. The characteristics and analog performance of the device were theoretically investigated by exploiting the electrical properties of a germanene nanoribbon and applying the doping concentration in the source and drain regions at 300 K and 4 K temperatures. The device parameters were obtained using a non-equilibrium Green’s function (NEGF) method within the tight binding (TB) Hamiltonian. The TB Hamiltonian was extracted from the density functional theory (DFT) through the Wannier function. We find that by increasing the doping concentration the I on current increases which leads to an improvement of the I on /I off ratio to 10 5 . Moreover, decreasing the temperature from 300 K to 4 K causes the I off to become ten times smaller. We find that the device output characteristic displays a negative differential conductance with a good peak-to-valley ratio which is improved by increasing the doping concentration. The analog performance of the device is also investigated in the subthreshold regime of operation by varying the doping concentration. It is observed that by increasing the device doping concentration, the analog figures of merit can be improved. (paper)

  17. Proximal femoral fractures

    DEFF Research Database (Denmark)

    Palm, Henrik; Teixidor, Jordi

    2015-01-01

    searched the homepages of the national heath authorities and national orthopedic societies in West Europe and found 11 national or regional (in case of no national) guidelines including any type of proximal femoral fracture surgery. RESULTS: Pathway consensus is outspread (internal fixation for un...

  18. Radiographic positions of femoral ACL, AM and PL centres : accuracy of guidelines based on the lateral quadrant method

    NARCIS (Netherlands)

    Luites, Joan W.H.; Verdonschot, Nico

    2017-01-01

    Purpose: Femoral tunnel positioning is an important factor in anatomical ACL reconstructions. To improve accuracy, lateral radiographic support can be used to determine the correct tunnel location, applying the quadrant method. Piefer et al. (Arthroscopy 28:872–881, 2012) combined various outcomes

  19. [Trochanteric femoral fractures].

    Science.gov (United States)

    Douša, P; Čech, O; Weissinger, M; Džupa, V

    2013-01-01

    At the present time proximal femoral fractures account for 30% of all fractures referred to hospitals for treatment. Our population is ageing, the proportion of patients with post-menopausal or senile osteoporosis is increasing and therefore the number of proximal femoral fractures requiring urgent treatment is growing too. In the age category of 50 years and older, the incidence of these fractures has increased exponentially. Our department serves as a trauma centre for half of Prague and part of the Central Bohemia Region with a population of 1 150 000. Prague in particular has a high number of elderly citizens. Our experience is based on extensive clinical data obtained from the Register of Proximal Femoral Fractures established in 1997. During 14 years, 4280 patients, 3112 women and 1168 men, were admitted to our department for treatment of proximal femoral fractures. All patients were followed up until healing or development of complications. In the group under study, 82% were patients older than 70 years; 72% of those requiring surgery were in their seventies and eighties. Men were significantly younger than women (pfractures were 2.3-times more frequent in women than in men. In the category under 60 years, men significantly outnumbered women (pfractures were, on the average, eight years older than the patients with intertrochanteric fractures, which is a significant difference (pTrochanteric fractures accounted for 54.7% and femoral neck fractures for 45.3% of all fractures. The inter-annual increase was 5.9%, with more trochanteric than femoral neck fractures. There was a non-significant decrease in intertrochanteric (AO 31-A3) fractures. On the other hand, the number of pertrochanteric (AO 31-A1+2) fractures increased significantly (pfractures were treated with a proximal femoral nail; a short nail was used in 1260 and a long nail in 134 of them. A dynamic hip screw (DHS) was employed to treat 947 fractures. Distinguishing between pertrochanteric (21-A1

  20. Tunneling works. Tunnel koji

    Energy Technology Data Exchange (ETDEWEB)

    Higo, M [Hazam Gumi, Ltd., Tokyo (Japan)

    1991-10-25

    A mountain tunneling method for rock-beds used to be applied mainly to construction works in the mountains under few restrictions by environmental problems. However, construction works near residential sreas have been increasing. There are such enviromental problems due to tunneling works as vibration, noise, lowering of ground-water level, and influences on other structures. This report mainly describes the measurement examples of vibration and noise accompanied with blasting and the effects of the measures to lessen such influences. When the tunneling works for the railroad was carried out on the natural ground mainly composed of basalt, vibration of the test blasting was measured at three stations with piezoelectric accelerometers. Then, ordinary blasting, mutistage blasting, and ABM blasting methods were used properly besed on the above results, and only a few complaints were made. In the different works, normal noise and low-frequency sound were mesured at 22 stations around the pit mouth. As countermeasures for noise, sound-proof sheets, walls, and single and double doors were installed and foundto be effective. 1 ref., 6 figs., 1 tab.

  1. Iodixanol in femoral arteriography

    International Nuclear Information System (INIS)

    Thorstensen, Oe.; Albrechtsson, U.; Calissendorff, B.; Larusdottir, H.; Norgren, L.; Tengvar, M.; Bolstad, B.; Aspelin, P.

    1994-01-01

    Two contrast media, iodixanol (Visipaque, Nycomed) 270 mg I/ml and iohexol (Omnipaque, Nycomed) 300 mg I/ml, were compared in femoral arteriography, in 147 patients. Both contrast media were diagnostically effective for use in femoral arteriography, without any significant difference. Pain was reported in connection with injection of iohexol by 36% of the patients, after injection of iodixanol none reported pain. Seventy-two percent of the patients in the iodixanol group reported a sensation of warmth in connection with contrast injection versus 90% in the iohexol group. The average intensity of the warmth was greater with iohexol than with iodixanol. Fourteen percent of patients in the iodixanol group and 1% in the iohexol group reported one or more subjective adverse events. (orig.)

  2. Radiographic femoral varus measurement is affected unpredictably by femoral rotation

    DEFF Research Database (Denmark)

    Miles, James Edward

    Radiographic measurements of femoral varus are used to determine if intervention to correct femoral deformity is required, and to calculate the required correction. The varus angle is defined as the angle between the proximal femoral long axis (PFLA) and an axis tangential to the distal femoral...... and externally by 5° and 10° using plastic wedges. Accuracy of rotation was within +1°. Digital radiographs were obtained at each position. Varus angles were measured using ImageJ, employing two definitions of PFLA. Mean varus angles increased with 10° of either internal or external rotation with both PFLA...... rotation angles. The effect of rotation on varus angle measurements in these femoral specimens contradicts a previous report using CT. The most probable explanation is the difference in femoral positioning: the CT study used a slightly elevated position compared to that in this study, resulting in better...

  3. Treatment of the femoral neck peudoarthrosis in childhood: Case report

    Directory of Open Access Journals (Sweden)

    Vukašinović Zoran

    2013-01-01

    Full Text Available Introduction. Femoral neck fractures in children and adolescents are rare. However, their complications are frequent - avascular necrosis, femoral neck pseudoarthrosis, premature physeal closure with consequent growth disturbance and coxa vara deformity. Case Outline. A 9.5­year­old boy was injured in a car accident, and femoral neck fracture was diagnosed. Prior to admission at our hospital he was surgically treated several times. He was admitted at our hospital eight months following the accident. On the X­ray transcervical pseudoarthrosis of the femoral neck was found, as well as coxa vara deformity and metaphyseal avascular necrosis. He was operated at our hospital; all previously placed ostefixation material was removed, valgus osteotomy of 30 degrees was done as well as additional local osteoplasty using the commercial osteoindactive agent (Osteovit®. Postoperatively, we applied skin traction, bed rest and physical therapy. At the final follow­up, the patient was recovered completely. He is now painless, the legs are of equal length, range of movements in the left hip is full, life activity is normal. The X­ray shows that the femoral neck pseudoarthrosis is fully healed. Conclusion. This case is presented in order to encourage other colleagues to challenge the problematic situation such as this one. Also, we would like to remind them what one should think about and what should be taken into consideration in the primary treatment of femoral neck fractures in children. Valgus femoral osteotomy, as a part of the primary treatment of femoral neck fracture in children (identically as in the adults can prevent the occurrence of femoral neck pseudoarthrosis.

  4. Application of monorail fixator for femoral gap nonunion.

    Science.gov (United States)

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

    2014-01-01

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

  5. Structural and functional studies of bioobjects prepared from femoral heads

    Energy Technology Data Exchange (ETDEWEB)

    Kirilova, I. A., E-mail: IKirilova@niito.ru; Podorozhnaya, V. T., E-mail: VPodorognaya@niito.ru [Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan, 17, Frunze, Novosibirsk, 630091 (Russian Federation); Sharkeev, Yu. P., E-mail: sharkeev@ispms.tsc.ru [Institute of Strength Physics and Materials Science SB RAS, 2/4, pr. Akademicheskii, Tomsk, 634021 (Russian Federation); National Research Tomsk Polytechnic University, 30, Lenin Avenue, Tomsk, 634050 (Russian Federation); Popova, K. S., E-mail: kseniya@ispms.tsc.ru; Uvarkin, P. V., E-mail: uvarkin@ispms.tsc.ru [Institute of Strength Physics and Materials Science SB RAS, 2/4, pr. Akademicheskii, Tomsk, 634021 (Russian Federation)

    2015-11-17

    Results of examination of physicomechanical characteristics of samples of medial femoral head cuts are presented. The samples of medial femoral head cuts resected in 6 patients with coxarthrosis in primary endoprosthetic replacement of a coxofemoral joint have been tested for micro- and nanohardness. Young’s modulus and elemental composition of bone tissue have been investigated. To estimate the architectonics of cancellous tissue of the femoral head, adjacent cuts of the same patient have been analyzed. The porosity of bone tissue was estimated from macroscopic images obtained using macrophotography. The total porosity is calculated as the ratio of the total length of straight line segments overlapping pores to the total length of secants. A three-point bending test of the samples has shown that their strength changed from 0.187 to 1.650 MPa and their elasticity modulus changes from 1.69 to 8.15 MPa. The microhardness of the samples changes in the range 220–265 MPa and the average microhardness of medial femoral head cuts is 240 MPa. The elemental composition of medial femoral head cuts is represented by basic Ca, P, O, Na and Mg elements as well as by Sn, S, Fe, Cr, and C in microamounts. The atomic Ca to P ratio for bone tissue is 1.55. It is revealed that pores of the upper part of the femoral head have a more regular shape and in the lower part they are more elongated along the cut and occupy a larger volume. The lower part of the femoral head has a higher porosity (39 and 33%) than the upper part (34 and 30%). The total porosity of all samples does not exceed 37%.

  6. 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

  7. Focal femoral condyle resurfacing.

    LENUS (Irish Health Repository)

    Brennan, S A

    2013-03-01

    Focal femoral inlay resurfacing has been developed for the treatment of full-thickness chondral defects of the knee. This technique involves implanting a defect-sized metallic or ceramic cap that is anchored to the subchondral bone through a screw or pin. The use of these experimental caps has been advocated in middle-aged patients who have failed non-operative methods or biological repair techniques and are deemed unsuitable for conventional arthroplasty because of their age. This paper outlines the implant design, surgical technique and biomechanical principles underlying their use. Outcomes following implantation in both animal and human studies are also reviewed. Cite this article: Bone Joint J 2013;95-B:301-4.

  8. Radiological assessment of the femoral bowing in Japanese population

    Directory of Open Access Journals (Sweden)

    Abdelaal Ahmed Hamed Kassem

    2016-01-01

    Full Text Available Introduction: Differences in the magnitude of bowing between races are well-known characteristics of the femur. Asian races have an increased magnitude of femoral bowing but most of the orthopedic implants designed for the femur do not match this exaggerated bowing. We calculated the sagittal and coronal femoral bowing in the Japanese population at different levels of the femur and addressed its surgical significance. Material and methods: We calculated the sagittal and coronal bowing of 132 Japanese femora using CT scan of the femur. A mathematical calculation of the radius of curvature at proximal, middle, and distal regions of the femur was used to determine the degree of femoral bowing. Results: Mean sagittal bowing of the femur was 581, 188, and 161 mm for the proximal, middle, and distal thirds of the femur and mean lateral bowing was 528, 5092, and 876 mm, respectively. Mean sagittal and coronal bowing for the whole femur was 175 and 2640 mm, respectively. No correlation was found between age, gender, length of femur, and the degree of bowing. Conclusion: Our study reveals that femoral bowing in the Japanese population is 175 mm in the sagittal plane and 2640 mm in the coronal plane; these values are greater than the femoral bowing in other ethnic groups studied in the literature. This may result in varying degrees of mismatch between the western-manufactured femoral intramedullary implants and the Japanese femur. We recommend that orthopedic surgeons to accurately perform preoperative evaluation of the femoral bowing to avoid potential malalignment, rotation, and abnormal stresses between the femur and implant.

  9. Femoral head necrosis; Hueftkopfnekrose

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, J.; Scheurecker, G.; Scheurecker, A.; Stoeger, A.; Huber, A. [Roentgeninstitut am Schillerpark, Linz (Austria); Hofmann, S. [Orthopaedisches Landeskrankenhaus Stolzalpe (Austria)

    2009-05-15

    The epidemiology and pathohistogenesis of avascular femoral head necrosis has still not been clarified in detail. Because the course of the disease runs in stages and over a long time period nearly always culminates in the necessity for a total hip prosthesis, an exact radiological evaluation is of paramount importance for the treatment. There is a need for a common staging system to enable comparison of different therapy concepts and especially their long-term results. In this article the ARCO staging system is described in full detail, which includes all radiological modalities as well as histopathological alterations. (orig.) [German] Bei der avaskulaeren Femurkopfnekrose handelt es sich um ein Krankheitsbild, dessen Ursachen noch immer nicht vollstaendig geklaert sind. Da die Erkrankung stadienhaft verlaeuft und ueber einen laengeren Zeitraum betrachtet nahezu immer in einem prothetischen Hueftersatz muendet, ist eine genaue radiologische Abklaerung fuer die Behandlung von enormer Bedeutung. Um Langzeiterfolge verschiedener Therapiekonzepte vergleichen zu koennen, sind eine exakte Beschreibung und darauf basierend die Verwendung einer einheitlichen Stadieneinteilung wuenschenswert. In der vorliegenden Arbeit wird die ARCO-Stadieneinteilung im Detail beschrieben, die alle bildgebenden Methoden beruecksichtigt und histopathologische Veraenderungen mit einbezieht. (orig.)

  10. Tunneling Flight Time, Chemistry, and Special Relativity.

    Science.gov (United States)

    Petersen, Jakob; Pollak, Eli

    2017-09-07

    Attosecond ionization experiments have not resolved the question "What is the tunneling time?". Different definitions of tunneling time lead to different results. Second, a zero tunneling time for a material particle suggests that the nonrelativistic theory includes speeds greater than the speed of light. Chemical reactions, occurring via tunneling, should then not be considered in terms of a nonrelativistic quantum theory calling into question quantum dynamics computations on tunneling reactions. To answer these questions, we define a new experimentally measurable paradigm, the tunneling flight time, and show that it vanishes for scattering through an Eckart or a square barrier, irrespective of barrier length or height, generalizing the Hartman effect. We explain why this result does not lead to experimental measurement of speeds greater than the speed of light. We show that this tunneling is an incoherent process by comparing a classical Wigner theory with exact quantum mechanical computations.

  11. Histological Observation of Regions around Bone Tunnels after Compression of the Bone Tunnel Wall in Ligament Reconstruction

    International Nuclear Information System (INIS)

    Maeda, Shintaro; Ishikawa, Hiroki; Tanigawa, Naoaki; Miyazaki, Kyosuke; Shioda, Seiji

    2012-01-01

    The objectives of this study were to investigate the time-course of influence of compression of bone tunnel wall in ligament reconstruction on tissue around the bone tunnel and to histologically examine the mechanism of preventing the complication of bone tunnel dilation, using rabbit tibia. A model in which the femoral origin of the extensor digitorum longus tendon was cut and inserted into a bone tunnel made proximal to the tibia was prepared in the bilateral hind legs of 20 Japanese white rabbits. In each animal, a tunnel was made using a drill only in the right leg, while an undersized bone tunnel was made by drilling and then dilated by compression using a dilator to the same tunnel size as that in the right leg. Animals were sacrificed at 0, 2, 4, 8 and 12 weeks after surgery (4 animals at each time point). Observation of bone tunnels by X-ray radiography showed osteosclerosis in the 2- and 4-week dilation groups. Osteosclerosis appeared as white lines around the bone tunnel on X-ray radiography. This suggests that dilation promotes callus formation in the bone tunnel wall and prevents the complication of bone tunnel enlargement after ligament reconstruction

  12. Femoral revision with impaction allografting and an uncemented femoral component

    DEFF Research Database (Denmark)

    Nickelsen, T N; Erenbjerg, M; Retpen, J B

    2008-01-01

    A technique for uncemented revision of the femoral component which combines impaction allografting and the use of a long-stemmed proximally coated titanium prostheses (Bimetric, Biomet Inc.) is described. The results after a mean follow-up of 112 months are reported. From 1991 to 1995 femoral...... implants 88% had no pain, 10% had slight pain and only 2% had severe pain. Thirty-eight patients had radiographic signs of remodelling of the graft and/or cortical repair. In cases with a successful outcome, the results have been encouraging in relation to clinical performance, regeneration of bone...

  13. Widening of the femoral proximal diaphysis--metaphysis angle in fetuses with achondroplasia.

    Science.gov (United States)

    Khalil, A; Morales-Roselló, J; Morlando, M; Bhide, A; Papageorghiou, A; Thilaganathan, B

    2014-07-01

    It has recently been reported that fetuses with achondroplasia have a wider than expected femoral proximal diaphysis-metaphysis angle (femoral angle). The aim of this case-control study was to investigate this finding. Cases with confirmed achondroplasia (n = 6), small-for-gestational-age fetuses (n = 70) and a group of normal fetuses (n = 377) were included in this study. The ultrasound image of the femur was examined by two independent experienced observers blinded to the diagnosis, who measured the femoral angle. These values were converted into multiples of the expected median (MoM), after adjustment for gestational age and femur length. Prevalence of various prenatal ultrasound signs of achondroplasia was determined in affected fetuses. Intra- and interobserver agreement of measurement of femoral angle was assessed using 95% limits of agreement and kappa statistics. The femoral angle can be measured accurately by ultrasound, and increases with both increasing gestational age and increasing femur length. The femoral angle-MoM was significantly higher in fetuses with achondroplasia than in the control group (1.36 vs 1.00 MoM, P achondroplasia (83.3%), which was the most consistent finding other than shortening of the long bones. The femoral angle is wider in fetuses with achondroplasia. This new ultrasound sign appears promising as an additional discriminatory marker when clinicians are faced with a case of short long bones in the third trimester. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  14. Proximal Femoral Geometry and the Risk of Fractures: Literature Review

    Directory of Open Access Journals (Sweden)

    N.V. Grygorieva

    2016-02-01

    Full Text Available This article presents the literature review of the impact of the upper third of the femur geometry (hip axis length, femoral neck angle, inter-trochanteric length, horizontal offset, thickness of the cortical bone, etc. on the risk of fractures. The article demonstrates the capabilities of techniques for measurement of hip geometry, namely conventional X-ray of pelvic bones, dual-energy X-ray absorptiometry, computed tomography. Possible correlation is shown between some genetic markers and features of the geometry of the upper third of the femur. Also, there are presented the results of own researches of age and sex characteristics of proximal hip geometry parameters in patients without fractures, as well as in patients of older age groups with internal and extraarticular femoral fractures.

  15. Spin dynamics in tunneling decay of a metastable state

    OpenAIRE

    Ban, Yue; Sherman, E. Ya.

    2012-01-01

    We analyze spin dynamics in the tunneling decay of a metastable localized state in the presence of spin-orbit coupling. We find that the spin polarization at short time scales is affected by the initial state while at long time scales both the probability- and the spin density exhibit diffraction-in-time phenomenon. We find that in addition to the tunneling time the tunneling in general can be characterized by a new parameter, the tunneling length. Although the tunneling length is independent...

  16. Application of monorail fixator for femoral gap nonunion

    Directory of Open Access Journals (Sweden)

    Agrawal Hemendra Kumar

    2014-07-01

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

  17. Recognition tunneling

    Czech Academy of Sciences Publication Activity Database

    Lindsay, S.; He, J.; Sankey, O.; Hapala, Prokop; Jelínek, Pavel; Zhang, P.; Chang, S.; Huang, S.

    2010-01-01

    Roč. 21, č. 26 (2010), 262001/1-262001/12 ISSN 0957-4484 R&D Projects: GA ČR GA202/09/0545 Institutional research plan: CEZ:AV0Z10100521 Keywords : STM * tunneling current * molecular electronics * DFT calculations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.644, year: 2010

  18. Anatomic landmarks of fluoroscopy guided puncture of the pulseless femoral artery

    International Nuclear Information System (INIS)

    Jeon, Min Hee; Han, Gi Seok; Kim, Sung Jin; Park, Kil Sun; Cha, Sang Hoon; Bae, Il Hun; Lee, Seung Young

    2006-01-01

    We wanted to improve puncturing the pulseless femoral artery by evaluating the anatomic landmarks that suggest the course of the femoral artery on fluoroscopy. We analyzed 37 hemipelvis spot images that were centered on the arterial sheath after puncture of the femoral artery. The inguinal angles were measured between the inguinal line connecting the anterior superior iliac spine and the symphysis pubis, and the line of the arterial sheath. Inguinal ligament ratios were measured as the distance from the symphysis pubis to the arterial sheath to the length of the inguinal ligament on the inguinal line. The femoral head ratios were measured as the distance from the medial margin of the femur head to the arterial sheath to the transverse length of the femur head. The mean inguinal angle was 66.5 and the mean inguinal ligament ratio was 0.42 (± 0.03). The mean femoral head ratio was 0.08 (± 0.18). In comparing the men and women, there was no significant difference in the inguinal angle and the femoral head ratio, but the inguinal distance ratio was larger in women (men: 0.41 ± 0.033, women: 0.44 ± 0.031, ρ < 0.05). The femoral artery generally courses just lateral to the medial margin of the femur head (femoral head ratio: 0.08) and the medial 40% of the inguinal ligament (inguinal ligament ratio: 0.42). So, consideration of these relations may be helpful for puncturing the pulseless femoral artery

  19. 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.

  20. Tunnel - history of

    International Nuclear Information System (INIS)

    1998-11-01

    This book introduces history of tunnel in ancient times, the middle ages and modern times, survey of tunnel and classification of bedrock like environment survey of position, survey of the ground, design of tunnel on basic thing of the design, and design of tunnel of bedrock, analysis of stability of tunnel and application of the data, construction of tunnel like lattice girder and steel fiber reinforced shot crete, and maintenance control and repair of tunnel.

  1. Radiographic landmarks for locating the femoral origin of the superficial medial collateral ligament.

    Science.gov (United States)

    Hartshorn, Timothy; Otarodifard, Karimdad; White, Eric A; Hatch, George F Rick

    2013-11-01

    Little has been written about the use of radiographic landmarks for locating the origin of the superficial medial collateral ligament (sMCL). A standardized radiographic landmark for the sMCL origin using intraoperative fluoroscopic imaging may be of value in aiding the surgeon in accurate femoral tunnel placement in the setting of extensive soft tissue disruption and bony attrition. To determine a reproducible radiographic landmark that will assist in correct femoral tunnel placement in sMCL repair and reconstruction. Descriptive laboratory study. Ten fresh-frozen unmatched human cadaveric knees were dissected, and the origin of the sMCL was exposed. A 2-mm metallic marker was then placed at the center of the femoral origin of the sMCL. True lateral fluoroscopically assisted digital radiographs were obtained of the knee with the posterior and distal femoral condyles overlapping in a standardized fashion. With the use of computer software, reference lines were drawn on the images, creating 4 quadrants. Two independent examiners performed quantitative measurements of the sMCL origin in relation to this axis and to the Blumensaat line. Mean measurements showed the sMCL origin to be closely related to the intersection point of the Blumensaat line and a line drawn distally from the posterior femoral cortex on a true lateral radiograph. The sMCL origin was found at a mean point 1.6 ± 4.3 mm posterior and 4.9 ± 2.1 mm proximal to the intersection of a line paralleling the posterior femoral cortex and a line drawn perpendicular to the posterior femoral cortical line, where it intersects the Blumensaat line. In 5 of 10 specimens, the center of the sMCL origin fell precisely on the Blumensaat line. The remaining specimens had sMCL origins anterior to the Blumensaat line. The femoral origin of the sMCL was found in the proximal and posterior quadrants in 8 of 10 specimens. With a relatively small amount of deviation, the sMCL origin can be consistently identified on a true

  2. Fundamental length and relativistic length

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1988-01-01

    It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem

  3. Flame Length

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Flame length was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  4. Mammary and femoral hydatid cysts.

    Science.gov (United States)

    Shamim, Muhammad

    2010-08-01

    Hydatid cyst disease most commonly affects liver and lungs, but it can affect all viscera and soft tissues of the body. Simultaneous mammary and femoral hydatid cysts, without any other visceral involvement, are extremely rare. This is a case report of 25-years-old female, presenting with lump in left breast mimicking fibroadenoma and lump in right thigh mimicking fibroma. Both turned out to be hydatid cysts.

  5. Carpal Tunnel Syndrome

    Science.gov (United States)

    ... a passing cramp? It could be carpal tunnel syndrome. The carpal tunnel is a narrow passageway of ... three times more likely to have carpal tunnel syndrome than men. Early diagnosis and treatment are important ...

  6. Removal of a broken guide wire entrapped in a fractured femoral neck

    Directory of Open Access Journals (Sweden)

    ZHU Qing-hua

    2013-08-01

    Full Text Available 【Abstract】Guide wire plays an important role in the fixation of femoral neck fracture with dynamic hip screw (DHS. Breakage of a guide wire during operation is a very rare condition. We met such a dilemma in DHS fixation of a 54-year-old male patient who sustained Garden type IV frac-ture of the right femoral neck. The distal end of the guide wire broke and was entrapped in the fractured femoral neck. We tried to get the broken part out by a cannulated drill. Reaming was started with the cannulated drill slowly rotat-ing around the guide K-wire until the reamer fully contained the target under fluoroscope. A bone curette was used to get the broken wire out but failed, so we had to use the cannuated drill to dredge this bone tunnel. Finally the bro-ken wire end was taken out, mixed with blood and bone fragments. Through the existing drilling channel, DHS fixa-tion was easily finished. The patient had an uneventful re-covery without avascular necrosis of femoral head or non-union of the fracture at one year’s follow-up. A few methods can be adopted to deal with the broken guide wire. The way used in our case is less invasive but technically challenging. When the guide wire is properly positioned, this method is very practical and useful. Key words: Femoral neck fractures; Bones wires; Complications

  7. Drill and blast tunnelling; Konvensjonell drift av tunneler

    Energy Technology Data Exchange (ETDEWEB)

    Roenn, Paal-Egil

    1997-12-31

    This thesis treats drill and blast tunnelling. The rapid technological advance necessitates revised and updated design criteria, quality requirements and quality control. In situ blast experiments were carried out in order to test new methods and improve the basis for calculation and design. The main topics of the experiments were (1) longer rounds and increased drillhole diameter, (2) emulsion slurry as explosives in tunnelling, and (3) electronic detonators in contour blasting. The experiments show that it is technically feasible to blast rounds of up to 8.6 m length. Using current technology, the economical optimum round length is substantially shorter. Dust, low visibility, noise and toxic fumes are occupational environmental strains for the tunnel workers. Several of the environmental factors are strongly influenced by the type of explosives used. For example, emulsion slurry resulted in 4 to 5 times better visibility than Anolit and the concentration of respirable dust and total dust was reduced by 30-50 %. Electronic detonators were tested and found to give a higher percentage of remaining drillholes in the contour than Nonel detonators. The thesis includes a chapter on economic design of hydropower tunnels. 42 refs., 83 figs., 45 tabs.

  8. Three-Dimensional Analysis of the Curvature of the Femoral Canal in 426 Chinese Femurs

    Directory of Open Access Journals (Sweden)

    Xiu-Yun Su

    2015-01-01

    Full Text Available Purpose. The human femur has long been considered to have an anatomical anterior curvature in the sagittal plane. We established a new method to evaluate the femoral curvature in three-dimensional (3D space and reveal its influencing factors in Chinese population. Methods. 3D models of 426 femurs and the medullary canal were constructed using Mimics software. We standardized the positions of all femurs using 3ds Max software. After measuring the anatomical parameters, including the radius of femoral curvature (RFC and banking angle, of the femurs using the established femur-specific coordinate system, we analyzed and determined the relationships between the anatomical parameters of the femur and the general characteristics of the population. Results. Pearson’s correlation analyses showed that there were positive correlations between the RFC and height (r=0.339, p<0.001 and the femoral length and RFC (r=0.369, p<0.001 and a negative correlation between the femoral length and banking angle (r=-0.223, p<0.001. Stepwise linear regression analyses showed that the most relevant factors for the RFC and banking angle were the femoral length and gender, respectively. Conclusions. This study concluded that the banking angle of the femur was significantly larger in female than in male.

  9. Tunneling technologies for the collider ring tunnels

    International Nuclear Information System (INIS)

    Frobenius, P.

    1989-01-01

    The Texas site chosen for the Superconducting Super Collider has been studied, and it has been determined that proven, conventional technology and accepted engineering practice are suitable for constructing the collider tunnels. The Texas National Research Laboratory Commission report recommended that two types of tunneling machines be used for construction of the tunnels: a conventional hard rock tunnel boring machine (TBM) for the Austin chalk and a double shielded, rotary TBM for the Taylor marl. Since the tunneling machines usually set the pace for the project, efficient planning, operation, and coordination of the tunneling system components will be critical to the schedule and cost of the project. During design, tunneling rate prediction should be refined by focusing on the development of an effective tunneling system and evaluating its capacity to meet or exceed the required schedules. 8 refs., 13 figs

  10. A Morphological Insight of the Femoral Vein

    Directory of Open Access Journals (Sweden)

    Ferreira AH

    2015-10-01

    Full Text Available A total of 13 cadavers (12 men and 1 women of different age group were used for the study with the purpose to determine the prevalence of femoral vein duplication. Lower limb regions (26 sides were carefully dissected as per the standard dissection procedure. Femoral vein (unitruncular was found in 96.15% of specimen. Bitruncular configurations (total bifidity was found in a male cadaver of 75 years of age (3.85%. In the right lower limb, 6.5 cms below the inguinal ligament the femoral vein - lateral ramus received the lateral circumflex femoral vein, and the medial circumflex femoral vein, and the lateral and medial ramii formed a common venous trunk. Knowledge of the truncular venous variations is important to recognize and avoid potential errors in diagnosis of deep venous thrombosis of the femoral vein, in the case of an occluded duplicated trunk.

  11. Evaluation of perfusion of the femoral head after femoral neck fracture using bone scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Satoshi; Ishido, Yasuhiro [Saiseikai Sendai Hospital, Kagoshima (Japan); Okano, Toshihiro [Ibusuki National Hospital, Kagoshima (Japan); Komiya, Setsuro [Kagoshima Univ. (Japan). Faculty of Medicine

    2002-09-01

    We treated 13 patients for femoral neck fracture. They consisted of 2 males and 11 females, and were classified according to Garden stage classification; Stage I, 3 cases; Stage II, 2 cases; Stage III, 2 cases; Stage IV, 4 cases. Two trochanteric fracture cases were used by control. We evaluated perfusion of the femoral head after femoral neck fracture using bone scintigraphy, which is considered useful for evaluation of perfusion of the femoral neck before operation. (author)

  12. Evaluation of perfusion of the femoral head after femoral neck fracture using bone scintigraphy

    International Nuclear Information System (INIS)

    Yamaguchi, Satoshi; Ishido, Yasuhiro; Okano, Toshihiro; Komiya, Setsuro

    2002-01-01

    We treated 13 patients for femoral neck fracture. They consisted of 2 males and 11 females, and were classified according to Garden stage classification; Stage I, 3 cases; Stage II, 2 cases; Stage III, 2 cases; Stage IV, 4 cases. Two trochanteric fracture cases were used by control. We evaluated perfusion of the femoral head after femoral neck fracture using bone scintigraphy, which is considered useful for evaluation of perfusion of the femoral neck before operation. (author)

  13. Fundamental length

    International Nuclear Information System (INIS)

    Pradhan, T.

    1975-01-01

    The concept of fundamental length was first put forward by Heisenberg from purely dimensional reasons. From a study of the observed masses of the elementary particles known at that time, it is sumrised that this length should be of the order of magnitude 1 approximately 10 -13 cm. It was Heisenberg's belief that introduction of such a fundamental length would eliminate the divergence difficulties from relativistic quantum field theory by cutting off the high energy regions of the 'proper fields'. Since the divergence difficulties arise primarily due to infinite number of degrees of freedom, one simple remedy would be the introduction of a principle that limits these degrees of freedom by removing the effectiveness of the waves with a frequency exceeding a certain limit without destroying the relativistic invariance of the theory. The principle can be stated as follows: It is in principle impossible to invent an experiment of any kind that will permit a distintion between the positions of two particles at rest, the distance between which is below a certain limit. A more elegant way of introducing fundamental length into quantum theory is through commutation relations between two position operators. In quantum field theory such as quantum electrodynamics, it can be introduced through the commutation relation between two interpolating photon fields (vector potentials). (K.B.)

  14. Avascular Necrosis in the Contralateral Hip in Patients With Congenital Femoral Deficiency: A Report of 3 Cases.

    Science.gov (United States)

    Brown, Timothy S; Wimberly, Robert L; Birch, John G

    2017-01-01

    Congenital femoral deficiency is an uncommon clinical entity. We report 3 patients who developed avascular necrosis of the hip in the long (normal) leg during longitudinal observation and/or treatment of congenital femoral deficiency. Patients were identified in limb length discrepancy clinic and their charts were retrospectively reviewed for clinical and radiographic data collection. We describe the occurrence of idiopathic avascular necrosis in the normal limb in patients being followed for limb length discrepancy. Although no conclusion could be drawn about the etiology of the avascular necrosis, we describe a previously undocumented relationship between congenital femoral deficiency and avascular necrosis in the contralateral hip. This occurred in our congenital femoral deficiency population at a rate higher than expected compared with published incidences of avascular necrosis of the hip in children. Level IV-case series.

  15. Anatomic variability of the vascularized composite osteomyocutaneous flap from the medial femoral condyle: an anatomical study

    Directory of Open Access Journals (Sweden)

    Trung-Hau Le Thua

    2014-12-01

    Full Text Available Aim: The anatomical study and clinical application for the vascularized corticoperiosteal flap from the medial femoral condyle have been performed and described previously. Although prior studies have described the composite osteomyocutaneous flap from the medial femoral condyle, a detailed analysis of the vascularity of this region has not yet been fully evaluated. Methods: This anatomical study described the variability of the arteries from the medial femoral condyle in 40 cadaveric specimens. Results: The descending genicular artery (DGA was found in 33 of 40 cases (82.5%. The  superomedial genicular artery (SGA was present in 10 cases (25%. All 33 cases (100% of the DGA had articular branches to the periosteum of the medial femoral condyle. Muscular branches and saphenous branches of the DGA were present in 25 cases (62.5% and 26 cases (70.3%, respectively. Conclusion: The current study demonstrates that the size and length of the vessels to the medial femoral condyle are sufficient for a vascularized bone flap. A careful preoperative vascular assessment is essential prior to use of the vascularized composite osteomyocutaneous flap from the medial femoral condyle, because of the considerable anatomical variations in different branches of the DGA.

  16. The surgical treatment of ilio-femoral venous obstruction.

    Science.gov (United States)

    Illuminati, G; Caliò, F G; D'Urso, A; Mancini, P; Papaspyropoulos, V; Ceccanei, G; Lorusso, R; Vietri, F

    2004-01-01

    A series of 9 patients of a mean age of 48 years, operated on for compression of the ilio-femoral venous axis is reported. The cause of obstruction was external compression in 3 cases, a retroperitoneal sarcoma in 1 case, and an infrarenal aortic aneurysm in 2. Two patients presented with a Cockett's syndrome, 3 with a chronic ilio-femoral thrombosis, and one with a post-traumatic segmentary stenosis. Treatment consisted in a resection/Dacron grafting of 2 infrarenal aortic aneurysms, one femoro-caval bypass graft, 2 transpositions of the right common iliac artery in the left hypogastric artery for Cockett's syndrome, 3 Palma's operations for chronic thrombosis, and one internal jugular vein interposition for segmentary stenosis. There were no postoperative deaths and no early thromboses of venous reconstructions performed. All the patients were relieved of symptoms during the follow-up period, whose mean length was 38 months. The cause of venous obstruction and the presence of symptoms which are resistant to medical treatment are the main indications to ilio-femoral venous revascularization. The choice of the optimal treatment in each single case yields satisfactory results.

  17. Three-stage treatment protocol for recalcitrant distal femoral nonunion.

    Science.gov (United States)

    Ma, Ching-Hou; Chiu, Yen-Chun; Tu, Yuan-Kun; Yen, Cheng-Yo; Wu, Chin-Hsien

    2017-04-01

    In this study, we proposed a three-stage treatment protocol for recalcitrant distal femoral nonunion and aimed to analyze the clinical results. We retrospective reviewed 12 consecutive patients with recalcitrant distal femoral nonunion undergoing our three-stage treatment protocol from January 2010 to December 2014 in our institute. The three-stage treatment protocol comprised debridement of the nonunion site, lengthening to eliminate leg length discrepancy, deformity correction, stabilization with a locked plate, filling of the defect with cement spacer for inducing membrane formation, and bone reconstruction using a cancellous bone autograft (Masquelet technique) or free vascularized fibular bone graft. The bone union time, wound complication, lower limbs alignment, amount of lengthening, knee range of motion, and functional outcomes were evaluated. Osseous union with angular deformity lengthening was 5.88 cm (range 3.5-12 cm). Excellent or good outcomes were obtained in 9 patients. Although the current study involved only a small number of patients and the intervention comprised three stages, we believe that such a protocol may be a valuable alternative for the treatment of recalcitrant distal femoral nonunion.

  18. Atrophic femoral nonunion with bone loss: treatment with monorail transport: a case report.

    Science.gov (United States)

    Gay, David M; Voss, Frank R

    2004-08-01

    Nonunions are an uncommon outcome of femoral fractures. Atrophic nonunions with a leg length discrepancy secondary to bone loss are often the most difficult to treat, and the treatment options are limited. We present a case that uses concomitant monolateral external fixation and intramedullary nailing to heal a nonunion and perform a simultaneous 7-cm lengthening procedure in a 33-year-old female.

  19. The tridimensional geometry of the proximal femur should determine the design of cementless femoral stem in total hip arthroplasty.

    Science.gov (United States)

    Wegrzyn, Julien; Roux, Jean-Paul; Loriau, Charlotte; Bonin, Nicolas; Pibarot, Vincent

    2018-02-22

    Using a cementless femoral stem in total hip arthroplasty (THA), optimal filling of the proximal femoral metaphyseal volume (PFMV) and restoration of the extramedullary proximal femoral (PF) parameters (i.e., femoral offset (FO), neck length (FNL), and head height (FHH)) constitute key goals for optimal hip biomechanics, functional outcome, and THA survivorship. However, almost 30% of mismatch between the PF anatomy and implant geometry of the most widely implanted non-modular cementless femoral stem has been demonstrated in a computed tomography scan (CT scan) study. Therefore, this anatomic study aimed to evaluate the relationship between the intra- and extramedullary PF parameters using tridimensional CT scan reconstructions. One hundred fifty-one CT scans of adult healthy hips were obtained from 151 male Caucasian patients (mean age = 66 ± 11 years) undergoing lower limb CT scan arteriography. Tridimensional PF reconstructions and parameter measurements were performed using a corrected PF coronal plane-defined by the femoral neck and diaphyseal canal longitudinal axes-to avoid influence of PF helitorsion and femoral neck version on extramedullary PF parameters. Independently of the femoral neck-shaft angle, the PFMV was significantly and positively correlated with the FO, FNL, and FHH (r = 0.407 to 0.420; p < 0.0001). This study emphasized that the tridimensional PF geometry measurement in the corrected coronal plane of the femoral neck can be useful to determine and optimize the design of a non-modular cementless femoral stem. Particularly, continuous homothetic size progression of the intra- and extramedullary PF parameters should be achieved to assure stem fixation and restore anatomic hip biomechanics.

  20. Measurement of bone mineral density in the tunnel regions for anterior cruciate ligament reconstruction by dual-energy X-ray absorptiometry, computed tomography scan, and the immersion technique based on Archimedes' principle.

    Science.gov (United States)

    Tie, Kai; Wang, Hua; Wang, Xin; Chen, Liaobin

    2012-10-01

    To determine, for anterior cruciate ligament (ACL) reconstruction, whether the bone mineral density (BMD) of the femoral tunnel was higher than that of the tibial tunnel, to provide objective evidence for choosing the appropriate diameter of interference screws. Two groups were enrolled. One group comprised 30 normal volunteers, and the other comprised 9 patients with ACL rupture. Dual-energy X-ray absorptiometry was used to measure the BMD of the femoral and tibial tunnel regions of the volunteers' right knees by choosing a circular area covering the screw fixation region. The knees were also scanned by spiral computed tomography (CT), and the 3-dimensional reconstruction technique was used to determine the circular sections passing through the longitudinal axis of the femoral and tibial tunnels. Grayscale CT values of the cross-sectional area were measured. Cylindrical cancellous bone blocks were removed from the femoral and tibial tunnels during the ACL reconstruction for the patients. The volumetric BMD of the bone blocks was measured using a standardized immersion technique according to Archimedes' principle. As measured by dual-energy X-ray absorptiometry, the BMD of the femoral and tibial tunnel regions was 1.162 ± 0.034 g/cm(2) and 0.814 ± 0.038 g/cm(2), respectively (P difference in both femoral and tibial tunnel regions. For ACL reconstruction, the BMD of the femoral tunnel is higher than that of the tibial tunnel. This implies that a proportionally larger-diameter interference screw should be used for fixation in the proximal tibia than that used for fixation in the distal femur. Level IV, therapeutic case series. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  1. Treatment of neglected femoral neck fracture

    Directory of Open Access Journals (Sweden)

    Anil K Jain

    2015-01-01

    Full Text Available Intra-capsular femoral neck fractures are seen commonly in elderly people following a low energy trauma. Femoral neck fracture has a devastating effect on the blood supply of the femoral head, which is directly proportional to the severity of trauma and displacement of the fracture. Various authors have described a wide array of options for treatment of neglected/nonunion (NU femoral neck fracture. There is lack of consensus in general, regarding the best option. This Instructional course article is an analysis of available treatment options used for neglected femoral neck fracture in the literature and attempt to suggest treatment guides for neglected femoral neck fracture. We conducted the "Pubmed" search with the keywords "NU femoral neck fracture and/or neglected femoral neck fracture, muscle-pedicle bone graft in femoral neck fracture, fibular graft in femoral neck fracture and valgus osteotomy in femoral neck fracture." A total of 203 print articles were obtained as the search result. Thirty three articles were included in the analysis and were categorized into four subgroups based on treatment options. (a treated by muscle-pedicle bone grafting (MPBG, (b closed/open reduction internal fixation and fibular grafting (c open reduction and internal fixation with valgus osteotomy, (d miscellaneous procedures. The data was pooled from all groups for mean neglect, the type of study (prospective or retrospective, classification used, procedure performed, mean followup available, outcome, complications, and reoperation if any. The outcome of neglected femoral neck fracture depends on the duration of neglect, as the changes occurring in the fracture area and fracture fragments decides the need and type of biological stimulus required for fracture union. In stage I and stage II (Sandhu′s staging neglected femoral neck fracture osteosynthesis with open reduction and bone grafting with MPBG or Valgus Osteotomy achieves fracture union in almost 90

  2. Interfacial density of states in magnetic tunnel junctions

    NARCIS (Netherlands)

    LeClair, P.R.; Kohlhepp, J.T.; Swagten, H.J.M.; Jonge, de W.J.M.

    2001-01-01

    Large zero-bias resistance anomalies as well as a collapse of magnetoresistance were observed in Co/Al2O3/Co magnetic tunnel junctions with thin Cr interfacial layers. The tunnel magnetoresistance decays exponentially with nominal Cr interlayer thickness with a length scale of ~1 Å more than twice

  3. Subchondral insufficiency fractures of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.; Cassar-Pullicino, V.N. [Department of Radiology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom); Darby, A.J. [Department of Pathology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom)

    2004-02-01

    The aim of this study was to increase awareness of, and to show the variable clinical and radiological features of, subchondral insufficiency fractures of the femoral head. The clinical and radiological findings in 7 patients with subchondral insufficiency fractures of the femoral head were reviewed retrospectively. The diagnosis was confirmed histologically in 4 patients. Radiographs were performed in all patients, MRI in 5 and scintigraphy in 4 patients. Radiographs showed varying degrees of femoral head collapse in 4 patients. In the remaining 3 patients radiographs showed a normal femoral head, regional osteoporosis and focal sclerosis, respectively. Magnetic resonance imaging showed a low-signal band on T1- and T2-weighted images in the subchondral bone adjacent or parallel to the articular surface associated with bone marrow oedema. Scintigraphy showed increased uptake in the femoral head. Insufficiency fractures of the femoral head are easily overlooked or confused with avascular necrosis and, when there is significant joint destruction, osteoarthritis. Unsuspected insufficiency fracture of the femoral head can lead to significant and rapid loss of bone stock in osteoporotic patients waiting for arthroplasty for osteoarthritis. Increased awareness of this condition will hopefully lead to earlier diagnosis and a successful outcome of conservative treatment. (orig.)

  4. Frequency of ipsilateral femoral neck fractures in patients with ...

    African Journals Online (AJOL)

    Background: Ipsilateral associated femoral neck and shaft fractures are reported to occur in 2.5-6% of all femoral shaft fractures. Objective: To establish the frequency of ipsilateral femoral neck fractures amongst all patients presenting with femoral shaft fractures in Mulago Hospital. Methodology: This was a descriptive ...

  5. Transonic Dynamics Tunnel (TDT)

    Data.gov (United States)

    Federal Laboratory Consortium — The Transonic Dynamics Tunnel (TDT) is a continuous flow wind-tunnel facility capable of speeds up to Mach 1.2 at stagnation pressures up to one atmosphere. The TDT...

  6. Quantum theory of tunneling

    CERN Document Server

    Razavy, Mohsen

    2014-01-01

    In this revised and expanded edition, in addition to a comprehensible introduction to the theoretical foundations of quantum tunneling based on different methods of formulating and solving tunneling problems, different semiclassical approximations for multidimensional systems are presented. Particular attention is given to the tunneling of composite systems, with examples taken from molecular tunneling and also from nuclear reactions. The interesting and puzzling features of tunneling times are given extensive coverage, and the possibility of measurement of these times with quantum clocks are critically examined. In addition by considering the analogy between evanescent waves in waveguides and in quantum tunneling, the times related to electromagnetic wave propagation have been used to explain certain aspects of quantum tunneling times. These topics are treated in both non-relativistic as well as relativistic regimes. Finally, a large number of examples of tunneling in atomic, molecular, condensed matter and ...

  7. Road and Railroad Tunnels

    Data.gov (United States)

    Department of Homeland Security — Tunnels in the United States According to the HSIP Tiger Team Report, a tunnel is defined as a linear underground passageway open at both ends. This dataset is based...

  8. Hypersonic Tunnel Facility (HTF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypersonic Tunnel Facility (HTF) is a blow-down, non-vitiated (clean air) free-jet wind tunnel capable of testing large-scale, propulsion systems at Mach 5, 6,...

  9. Subtrochanteric femoral fracture during trochanteric nailing for the treatment of femoral shaft fracture.

    Science.gov (United States)

    Yun, Ho Hyun; Oh, Chi Hun; Yi, Ju Won

    2013-09-01

    We report on three cases of subtrochanteric femoral fractures during trochanteric intramedullary nailing for the treatment of femoral shaft fractures. Trochanteric intramedullary nails, which have a proximal lateral bend, are specifically designed for trochanteric insertion. When combined with the modified insertion technique, trochanteric intramedullary nails reduce iatrogenic fracture comminution and varus malalignment. We herein describe technical aspects of trochanteric intramedullary nailing for femoral shaft fractures to improve its application and prevent implant-derived complications.

  10. Tunneling magnetoresistance in Si nanowires

    KAUST Repository

    Montes Muñoz, Enrique

    2016-11-09

    We investigate the tunneling magnetoresistance of small diameter semiconducting Si nanowires attached to ferromagnetic Fe electrodes, using first principles density functional theory combined with the non-equilibrium Green\\'s functions method for quantum transport. Silicon nanowires represent an interesting platform for spin devices. They are compatible with mature silicon technology and their intrinsic electronic properties can be controlled by modifying the diameter and length. Here we systematically study the spin transport properties for neutral nanowires and both n and p doping conditions. We find a substantial low bias magnetoresistance for the neutral case, which halves for an applied voltage of about 0.35 V and persists up to 1 V. Doping in general decreases the magnetoresistance, as soon as the conductance is no longer dominated by tunneling.

  11. Stuffing the nail: A simple technique for the extraction of a broken femoral nail.

    Science.gov (United States)

    Lovell, Jane; Krishna, Damodaran; Gehr, Eugene

    2017-06-01

    The extraction of broken femoral nails can be a challenging procedure and surgeons should be familiar with many different techniques. This paper demonstrates a case study and new, simple and cost effective technique for the removal of broken cannulated femoral nails. Our technique uses two guide wires of variable diameter and had several key points of differentiation from previous methods. Firstly, stuffing the nail with guide wires of greater total diameter than the cannula; secondly, reversing the second guide wire and finally, bending the tips of the wires. These innovations allow the technique to be used for narrow cannulated nails, superior purchase along the length of the nail, easy wire insertion and limited soft tissue damage. Our technique for the removal of broken femoral nails is quick, effective, cheap and easy to replicate and can be used by any generalist orthopaedic surgeon with basic equipment.

  12. Ultrasound-Guided Femoral Nerve Block to Facilitate the Closed Reduction of a Dislocated Hip Prosthesis

    Directory of Open Access Journals (Sweden)

    Edward Carlin

    2017-10-01

    Full Text Available Prosthetic hip dislocation is a common but unfortunate complication in patients who have undergone total hip arthroplasty. Successful closed reduction in the emergency department leads to a reduced length of stay and rate of hospitalization. 1, 2 The use of regional anesthesia by femoral nerve block represents a novel approach for controlling pain in patients with hip pathologies. 3 Ultrasound-guided approaches have been used with great success for controlling pain in patients with hip fractures. 4, 5 Here we report the case of a 90-year-old male who presented with a dislocated hip prosthesis, which was subsequently corrected with closed reduction following delivery of regional anesthesia to the femoral nerve under ultrasound guidance. To our knowledge, this represents the first reported use of an ultrasound-guided femoral nerve block to facilitate closed reduction of a dislocated prosthetic hip, and highlights a novel approach that avoids the use of procedural sedation in an elderly patient.

  13. Profunda Anchor Technique for Ipsilateral Antegrade Approach in Endovascular Treatment of Superficial Femoral Artery Ostial Occlusion

    International Nuclear Information System (INIS)

    Pua, Uei

    2015-01-01

    Endovascular treatment of the superficial femoral artery (SFA) is challenging in the presence of flush ostial occlusion. One of the main challenges is the availability of access sites for intervention. Contralateral retrograde femoral access followed by cross-over and antegrade intervention while commonly used, may not be feasible in cases of altered iliac anatomy (e.g. kissing iliac stents). Ipsilateral antegrade intervention using common femoral artery (CFA) access in these instances while possible is typically challenging due to inadequate working length of the CFA for interrogation of the SFA ostium, compounded by the lack of sheath stability. The “profunda anchor” technique uses a buddy wire in the profunda femoris artery (PFA) to stabilize the sheath and allow catheter manipulation for antegrade intervention at the level of the SFA ostium. The PFA is further used as a conduit for deployment of closure device to avoid interference with the treated SFA

  14. Profunda Anchor Technique for Ipsilateral Antegrade Approach in Endovascular Treatment of Superficial Femoral Artery Ostial Occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Pua, Uei, E-mail: druei@yahoo.com [Tan Tock Seng Hospital, Department of Diagnostic Radiology (Singapore)

    2015-04-15

    Endovascular treatment of the superficial femoral artery (SFA) is challenging in the presence of flush ostial occlusion. One of the main challenges is the availability of access sites for intervention. Contralateral retrograde femoral access followed by cross-over and antegrade intervention while commonly used, may not be feasible in cases of altered iliac anatomy (e.g. kissing iliac stents). Ipsilateral antegrade intervention using common femoral artery (CFA) access in these instances while possible is typically challenging due to inadequate working length of the CFA for interrogation of the SFA ostium, compounded by the lack of sheath stability. The “profunda anchor” technique uses a buddy wire in the profunda femoris artery (PFA) to stabilize the sheath and allow catheter manipulation for antegrade intervention at the level of the SFA ostium. The PFA is further used as a conduit for deployment of closure device to avoid interference with the treated SFA.

  15. Structural and tunneling properties of Si nanowires

    KAUST Repository

    Montes Muñoz, Enrique

    2013-12-06

    We investigate the electronic structure and electron transport properties of Si nanowires attached to Au electrodes from first principles using density functional theory and the nonequilibrium Green\\'s function method. We systematically study the dependence of the transport properties on the diameter of the nanowires, on the growth direction, and on the length. At the equilibrium Au-nanowire distance we find strong electronic coupling between the electrodes and nanowires, which results in a low contact resistance. With increasing nanowire length we study the transition from metallic to tunneling conductance for small applied bias. For the tunneling regime we investigate the decay of the conductance with the nanowire length and rationalize the results using the complex band structure of the pristine nanowires. The conductance is found to depend strongly on the growth direction, with nanowires grown along the ⟨110⟩ direction showing the smallest decay with length and the largest conductance and current.

  16. Structural and tunneling properties of Si nanowires

    KAUST Repository

    Montes Muñ oz, Enrique; Gkionis, Konstantinos; Rungger, Ivan; Sanvito, Stefano; Schwingenschlö gl, Udo

    2013-01-01

    We investigate the electronic structure and electron transport properties of Si nanowires attached to Au electrodes from first principles using density functional theory and the nonequilibrium Green's function method. We systematically study the dependence of the transport properties on the diameter of the nanowires, on the growth direction, and on the length. At the equilibrium Au-nanowire distance we find strong electronic coupling between the electrodes and nanowires, which results in a low contact resistance. With increasing nanowire length we study the transition from metallic to tunneling conductance for small applied bias. For the tunneling regime we investigate the decay of the conductance with the nanowire length and rationalize the results using the complex band structure of the pristine nanowires. The conductance is found to depend strongly on the growth direction, with nanowires grown along the ⟨110⟩ direction showing the smallest decay with length and the largest conductance and current.

  17. Tunnelling through a Gaussian random barrier

    International Nuclear Information System (INIS)

    Bezak, Viktor

    2008-01-01

    A thorough analysis of the tunnelling of electrons through a laterally inhomogeneous rectangular barrier is presented. The barrier height is defined as a statistically homogeneous Gaussian random function. In order to simplify calculations, we assume that the electron energy is low enough in comparison with the mean value of the barrier height. The randomness of the barrier height is defined vertically by a constant variance and horizontally by a finite correlation length. We present detailed calculations of the angular probability density for the tunnelled electrons (i.e. for the scattering forwards). The tunnelling manifests a remarkably diffusive character if the wavelength of the electrons is comparable with the correlation length of the barrier

  18. Herniography off femoral, obturator and perineal hernias

    International Nuclear Information System (INIS)

    Ekberg, O.; Nordblom, I.; Fork, F.T.; Gullmo, A.

    1985-01-01

    Positive contrast herniography was used in the workup of 550 patients with unclear groin pain. The majority of these patients had rather characteristic hernias of indirect, direct or femoral type. However, now and then diagnostic problems arose. A femoral hernia may look like a direct or even obturator hernia. There is also a variety of multilocular femoral hernias and other types. A femoral hernia may be present together with other hernias in the ipsilateral or contralateral groin. Obturator hernias are usually small but are always confined to the obturator canal laterally in the obturator foramen. Abnormalities in the pouch of Douglas may include a deep rectogenital pouch, diverticula and true herniations. These uncommon herniographic findings are described and discussed. (orig.) [de

  19. SEX DETERMINATION FROM FEMORAL HEAD DIAMETERS IN ...

    African Journals Online (AJOL)

    hi-tech

    2000-03-01

    Mar 1, 2000 ... In medico-legal cases where sophisticated methods of sex determination is lacking, these ... scientific methods(3). Using the visual method ... between the sexes and the values of the right and left femoral head diameters.

  20. Using a calliper to restore the centre of the femoral head during total hip replacement.

    Science.gov (United States)

    Hill, J C; Archbold, H A P; Diamond, O J; Orr, J F; Jaramaz, B; Beverland, D E

    2012-11-01

    Restoration of leg length and offset is an important goal in total hip replacement. This paper reports a calliper-based technique to help achieve these goals by restoring the location of the centre of the femoral head. This was validated first by using a co-ordinate measuring machine to see how closely the calliper technique could record and restore the centre of the femoral head when simulating hip replacement on Sawbone femur, and secondly by using CT in patients undergoing hip replacement. Results from the co-ordinate measuring machine showed that the centre of the femoral head was predicted by the calliper to within 4.3 mm for offset (mean 1.6 (95% confidence interval (CI) 0.4 to 2.8)) and 2.4 mm for vertical height (mean -0.6 (95% CI -1.4 to 0.2)). The CT scans showed that offset and vertical height were restored to within 8 mm (mean -1 (95% CI -2.1 to 0.6)) and -14 mm (mean 4 (95% CI 1.8 to 4.3)), respectively. Accurate assessment and restoration of the centre of the femoral head is feasible with a calliper. It is quick, inexpensive, simple to use and can be applied to any design of femoral component.

  1. Bilateral femoral neck fractures following pelvic irradiation

    International Nuclear Information System (INIS)

    Mitsuda, Kenji; Nishi, Hosei; Oba, Hiroshi

    1977-01-01

    Over 300 cases of femoral neck fractures following radiotherapy for intrapelvic malignant tumor have been reported in various countries since Baensch reported this disease in 1927. In Japan, 40 cases or so have been reported, and cases of bilateral femoral neck fractures have not reached to ten cases. The authors experienced a case of 75 year-old female who received radiotherapy for cancer of the uterus, and suffered from right femoral neck fracture 3 months after and left femoral neck fracture one year and half after. As clinical symptoms, she had not previous history of trauma in bilateral femurs, but she complained of a pain in a hip joint and of gait disturbance. The pain in left femoral neck continued for about one month before fracture was recognized with roentgenogram. As histopathological findings, increase of fat marrow, decrease of bone trabeculae, and its marked degeneration were recognized. Proliferation of some blood vessels was found out, but thickness of the internal membrane and thrombogenesis were not recognized. Treatment should be performed according to degree of displacement of fractures. In this case, artificial joint replacement surgery was performed to the side of fracture of this time, because this case was bilateral femoral neck fractures and the patient had received artificial head replacement surgery in the other side of fracture formerly. (Tsunoda, M.)

  2. Proton tunneling in solids

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, J.

    1998-10-01

    The tunneling rate of the proton and its isotopes between interstitial sites in solids is studied theoretically. The phonons and/or the electrons in the solid have two effects on the tunneling phenomenon. First, they suppress the transfer integral between two neighbouring states. Second, they give rise to a finite lifetime of the proton state. Usually the second effect is large and the tunneling probability per unit time (tunneling rate) can be defined. In some cases, however, a coherent tunneling is expected and actually observed. (author)

  3. Proton tunneling in solids

    International Nuclear Information System (INIS)

    Kondo, J.

    1998-01-01

    The tunneling rate of the proton and its isotopes between interstitial sites in solids is studied theoretically. The phonons and/or the electrons in the solid have two effects on the tunneling phenomenon. First, they suppress the transfer integral between two neighbouring states. Second, they give rise to a finite lifetime of the proton state. Usually the second effect is large and the tunneling probability per unit time (tunneling rate) can be defined. In some cases, however, a coherent tunneling is expected and actually observed. (author)

  4. Subtrochanteric Femoral Fracture during Trochanteric Nailing for the Treatment of Femoral Shaft Fracture

    OpenAIRE

    Yun, Ho Hyun; Oh, Chi Hun; Yi, Ju Won

    2013-01-01

    We report on three cases of subtrochanteric femoral fractures during trochanteric intramedullary nailing for the treatment of femoral shaft fractures. Trochanteric intramedullary nails, which have a proximal lateral bend, are specifically designed for trochanteric insertion. When combined with the modified insertion technique, trochanteric intramedullary nails reduce iatrogenic fracture comminution and varus malalignment. We herein describe technical aspects of trochanteric intramedullary nai...

  5. 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.

  6. Outcome of non-operative management of femoral shaft fractures in children

    Directory of Open Access Journals (Sweden)

    Akinyoola A

    2011-01-01

    Full Text Available Background: Femoral shaft fractures are common injuries in childhood. There is paucity of information on their presentation and outcome of the available treatment methods in the African population. This study evaluated the outcome of non-operative methods of treatment of femoral shaft fractures in our centre. Patients and Methods: A retrospective review of the database of children aged 14 years and below with femoral shaft fractures treated non-operatively over a 10-year period. Results: A total of 134 patients with 138 fractures met the study criteria. This consisted of 71 boys (mean age = 6.1 years ± SD and 63 girls (mean age = 6.5 years ± SD. Pedestrian vehicular accident was the most common cause of femoral shaft fractures in the study population. The midshaft was the most common site of fractures. There were associated injuries to other parts of the body (especially head injury in 34.3% of the patients. The commonest mode of treatment was skin traction only (87.7%. The mean time to fracture union was 4.9 weeks ± SD (range = 3-15 weeks. The mean length of hospitalisation was 6.7 weeks ± SD (range = 5 days-11 weeks. There was a fairly strong positive correlation between the length of hospitalisation and the presence of associated injuries, especially head injury, upper limb fractures and bilaterality of the fractures. The mean total cost of treatment was #7685 (Naira or $51.2 (range = $14.2-$190. At the last follow up, 97.8% of the fractures united without significant angulation or shortening. Conclusion: The outcome of non-operative treatment of femoral shaft fractures in our setting is comparable to the results of other workers. Methods of treatment that shorten the length of hospitalisation without unduly increasing cost should be encouraged.

  7. Fire safety case study of a railway tunnel: Smoke evacuation

    Directory of Open Access Journals (Sweden)

    van Maele Karim

    2007-01-01

    Full Text Available When a fire occurs in a tunnel, it is of great importance to assure the safety of the occupants of the tunnel. This is achieved by creating smoke-free spaces in the tunnel through control of the smoke gases. In this paper, results are presented of a study concerning the fire safety in a real scale railway tunnel test case. Numerical simulations are performed in order to examine the possibility of natural ventilation of smoke in inclined tunnels. Several aspects are taken into account: the length of the simulated tunnel section, the slope of the tunnel and the possible effects of external wind at one portal of the tunnel. The Fire Dynamics Simulator of the National Institute of Standards and Technology, USA, is applied to perform the simulations. The simulations show that for the local behavior of the smoke during the early stages of the fire, the slope of the tunnel is of little importance. Secondly, the results show that external wind and/or pressure conditions have a large effect on the smoke gases inside the tunnel. Finally, some idea for the value of the critical ventilation velocity is given. The study also shows that computational fluid dynamics calculations are a valuable tool for large scale, real life complex fire cases. .

  8. Femoral component rotation in patellofemoral joint replacement.

    Science.gov (United States)

    van Jonbergen, Hans-Peter W; Westerbeek, Robin E

    2018-06-01

    Clinical outcomes in patellofemoral joint replacement may be related to femoral component rotation. Assessment of rotational alignment is however difficult as patients with isolated patellofemoral osteoarthritis often have trochlear dysplasia. The use of the medial malleolus as a landmark to guide rotation has been suggested. The purpose of our study was to evaluate this technique with regard to femoral component rotation, and to correlate rotation with clinical outcomes at one-year follow-up. Forty-one knees in 39 patients had patellofemoral joint replacement using the Zimmer Gender-Solutions patellofemoral prosthesis. Intraoperatively, we determined femoral component rotational alignment using an extramedullary rod aimed at the inferior tip of the medial malleolus. Postoperatively, we measured the angle between the femoral component and the anatomical transepicondylar axis using CT. The amount of rotation was correlated with clinical outcomes at one-year follow-up. Forty knees in 38 patients were available for one-year follow-up. Mean femoral component rotation relative to the anatomical transepicondylar axis was 1.4° external rotation (range, -3.8 to 5.7°). We found no statistically significant correlation between femoral component rotation and change from baseline KOOS subscales at one-year follow-up. Our findings show that when using the medial malleolus as a landmark to guide rotation, the femoral component of the patellofemoral prosthesis was oriented in external rotation relative to the anatomical transepicondylar axis in 80% of knees. Our study did not show a relation between the amount of external rotation and clinical outcomes. Level III. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Femoral rotation unpredictably affects radiographic anatomical lateral distal femoral angle measurements

    DEFF Research Database (Denmark)

    Miles, James Edward

    2016-01-01

    Objective: To describe the effects of internal and external femoral rotation on radiographic measurements of the anatomical lateral distal femoral angle (a-LDFA) using two methods for defining the anatomical proximal femoral axis (a-PFA). Methods: Digital radiographs were obtained of 14 right...... femora at five degree intervals from 10° external rotation to 10° internal rotation. Using freely available software, a-LDFA measurements were made using two different a-PFA by a single observer on one occasion. Results: Mean a-LDFA was significantly greater at 10° external rotation than at any other...... rotation. The response of individual femora to rotation was unpredictable, although fairly stable within ±5° of zero rotation. Mean a-LDFA for the two a-PFA methods differed by 1.5°, but were otherwise similarly affected by femoral rotation. Clinical significance: If zero femoral elevation can be achieved...

  10. Evaluation of a pig femoral head osteonecrosis model

    Directory of Open Access Journals (Sweden)

    Kim Harry

    2010-03-01

    Full Text Available Abstract Background A major cause of osteonecrosis of the femoral head is interruption of a blood supply to the proximal femur. In order to evaluate blood circulation and pathogenetic alterations, a pig femoral head osteonecrosis model was examined to address whether ligature of the femoral neck (vasculature deprivation induces a reduction of blood circulation in the femoral head, and whether transphyseal vessels exist for communications between the epiphysis and the metaphysis. We also tested the hypothesis that the vessels surrounding the femoral neck and the ligamentum teres represent the primary source of blood flow to the femoral head. Methods Avascular osteonecrosis of the femoral head was induced in Yorkshire pigs by transecting the ligamentum teres and placing two ligatures around the femoral neck. After heparinized saline infusion and microfil perfusion via the abdominal aorta, blood circulation in the femoral head was evaluated by optical and CT imaging. Results An angiogram of the microfil casted sample allowed identification of the major blood vessels to the proximal femur including the iliac, common femoral, superficial femoral, deep femoral and circumflex arteries. Optical imaging in the femoral neck showed that a microfil stained vessel network was visible in control sections but less noticeable in necrotic sections. CT images showed a lack of microfil staining in the epiphysis. Furthermore, no transphyseal vessels were observed to link the epiphysis to the metaphysis. Conclusion Optical and CT imaging analyses revealed that in this present pig model the ligatures around the femoral neck were the primary cause of induction of avascular osteonecrosis. Since the vessels surrounding the femoral neck are comprised of the branches of the medial and the lateral femoral circumflex vessels, together with the extracapsular arterial ring and the lateral epiphyseal arteries, augmentation of blood circulation in those arteries will improve

  11. Correlation of ultrasound appearance, gross anatomy, and histology of the femoral nerve at the femoral triangle.

    Science.gov (United States)

    Lonchena, Tiffany K; McFadden, Kathryn; Orebaugh, Steven L

    2016-01-01

    Correlation between ultrasound appearance, gross anatomic characteristics, and histologic structure of the femoral nerve (FN) is lacking. Utilizing cadavers, we sought to characterize the anatomy of the FN, and provide a quantitative measure of its branching. We hypothesize that at the femoral crease, the FN exists as a group of nerve branches, rather than a single nerve structure, and secondarily, that this transition into many branches is apparent on ultrasonography. Nineteen preserved cadavers were investigated. Ultrasonography was sufficient to evaluate the femoral nerve in nine specimens; gross dissection was utilized in all 19. Anatomic characteristics were recorded, including distances from the inguinal ligament to femoral crease, first nerve branch, and complete arborization of the nerve. The nerves from nine specimens were excised for histologic analysis. On ultrasound, the nerve became more flattened, widened, and less discrete as it coursed distally. Branching of the nerve was apparent in 12 of 18 images, with mean distance from inguinal ligament of 3.9 (1.0) cm. However, upon dissection, major branching of the femoral nerve occurred at 3.1 (1.0) cm distal to the inguinal ligament, well proximal to the femoral crease. Histologic analysis was consistent with findings at dissection. The femoral nerve arborizes into multiple branches between the inguinal ligament and the femoral crease. Initial branching is often high in the femoral triangle. As hypothesized, the FN exists as a closely associated group of nerve branches at the level of the femoral crease; however, the termination of the nerve into multiple branches is not consistently apparent on ultrasonography.

  12. Bone tunnel change develops within two weeks of double-bundle anterior cruciate ligament reconstruction using hamstring autograft: A comparison of different postoperative immobilization periods using computed tomography.

    Science.gov (United States)

    Shimizu, Ryo; Adachi, Nobuo; Ishifuro, Minoru; Nakamae, Atsuo; Ishikawa, Masakazu; Deie, Masataka; Ochi, Mitsuo

    2017-10-01

    The purpose of this study was to evaluate bone tunnel changes following anterior cruciate ligament (ACL) reconstruction during the early postoperative period using computed tomography (CT), and to understand the impact of postoperative immobilization on these changes. Twenty patients who underwent double-bundle ACL reconstruction using hamstring tendon autografts were included. We subcategorized patients into two groups: patients who underwent isolated ACL reconstruction and had three days of knee immobilization (Group A, n=10); and patients with concomitant meniscus injuries who underwent ACL reconstruction and meniscus repair simultaneously (Group B, n=10) had their knees immobilized for two weeks after surgery. Bone tunnel enlargement was evaluated using CT imaging at one to three days, two weeks, one month, three months and six months after surgery. The cross-sectional area of the femoral and tibial tunnels was measured, and enlargement rate was calculated. The tunnel center location at two weeks after surgery was also evaluated. The mean cross-sectional area adjacent to the joint space of the femoral and tibial tunnels significantly increased immediately after surgery, especially in the first month (P0.01). There was no significant difference in tunnel enlargement rate between group A and B. Tunnel center location changed even in the first two weeks. Bone tunnel enlargement following double-bundle ACL reconstruction occurred at an earlier time point after surgery than anticipated. Postoperative immobilization could not prevent bone tunnel enlargement, but might prevent tunnel migration. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Femoral head vitality after intracapsular hip fracture

    International Nuclear Information System (INIS)

    Stroemqvist, B.

    1983-01-01

    Femoral head vitality before, during and at various intervals from the operation was determined by tetracycline labeling and/or 99 sp (m)Tc-MDP scintimetry. In a three-year follow-up, healing prognosis could be determined by scintimetry 3 weeks from operation; deficient femoral head vitality predicting healing complications and retained vitality predicting uncomplicated healing. A comparison between pre- and postoperative scintimetry indicated that further impairment of the femoral head vitality could be caused by the operative procedure, and as tetracycline labeling prior to and after fracture reduction in 370 fractures proved equivalent, it was concluded that the procedure of osteosynthesis probably was responsible for capsular vessel injury, using a four-flanged nail. The four-flanged nail was compared with a low-traumatic method of osteosynthesis, two hook-pins, in a prospective randomized 14 month study, and the postoperative femoral head vitality was significantly better in the hook-pin group. This was also clearly demonstrated in a one-year follow-up for the fractures included in the study. Parallel to these investigations, the reliability of the methods of vitality determination was found satisfactory in methodologic studies. For clinical purpose, primary atraumatic osteosynthesis, postoperative prognostic scintimetry and early secondary arthroplasty when indicated, was concluded to be the appropriate approach to femoral neck fracture treatment. (Author)

  14. Avascular necrosis of the femoral head

    International Nuclear Information System (INIS)

    Kokubo, Takeshi; Takatori, Yoshio; Kamogawa, Morihide; Nakamura, Toshitaka; Ninomiya, Setsuo; Yoshikawa, Kohki; Itai, Yuji; Iio, Masahiro; Mitamura, Tadayuki

    1990-01-01

    T1-weighted MR images of thirty-six hips in 25 patients with avascular necrosis of the femoral head were obtained two to five times during the course of 2 to 26 months. We investigated these MR images in the light of the chronological change and compared them with plain radiographs. MR images changes in 16 femoral head; in general, the abnormal low intensity area in the femoral head reduced in extent and the internal high intensity area became smaller of disappeared. Thirteen femoral heads among them became more flattened on plain radiographs in the same period. It is noted that four different zones are defined in the femoral head after bone necrosis takes place: the dead bone marrow, the dead marrow which still contains fat, the reactive interface and the hyperemic bone marrow. In T1-weighted MR images, the dead bone marrow, the reactive interface and the hyperemic bone marrow are demonstrated as low intensity area, while the dead marrow containing fat may remain high in intensity. On the basis of this knowledge of histopathology and MR images of this disease, we suggest that reduction of the abnormal low intensity area and disappearance of the internal high intensity area on MR images can be regarded as diminution of hyperemia in the living bone marrow and loss of fat in the dead bone marrow, respectively. (author)

  15. Reliability of a semi-automated 3D-CT measuring method for tunnel diameters after anterior cruciate ligament reconstruction: A comparison between soft-tissue single-bundle allograft vs. autograft.

    Science.gov (United States)

    Robbrecht, Cedric; Claes, Steven; Cromheecke, Michiel; Mahieu, Peter; Kakavelakis, Kyriakos; Victor, Jan; Bellemans, Johan; Verdonk, Peter

    2014-10-01

    Post-operative widening of tibial and/or femoral bone tunnels is a common observation after ACL reconstruction, especially with soft-tissue grafts. There are no studies comparing tunnel widening in hamstring autografts versus tibialis anterior allografts. The goal of this study was to observe the difference in tunnel widening after the use of allograft vs. autograft for ACL reconstruction, by measuring it with a novel 3-D computed tomography based method. Thirty-five ACL-deficient subjects were included, underwent anatomic single-bundle ACL reconstruction and were evaluated at one year after surgery with the use of 3-D CT imaging. Three independent observers semi-automatically delineated femoral and tibial tunnel outlines, after which a best-fit cylinder was derived and the tunnel diameter was determined. Finally, intra- and inter-observer reliability of this novel measurement protocol was defined. In femoral tunnels, the intra-observer ICC was 0.973 (95% CI: 0.922-0.991) and the inter-observer ICC was 0.992 (95% CI: 0.982-0.996). In tibial tunnels, the intra-observer ICC was 0.955 (95% CI: 0.875-0.985). The combined inter-observer ICC was 0.970 (95% CI: 0.987-0.917). Tunnel widening was significantly higher in allografts compared to autografts, in the tibial tunnels (p=0.013) as well as in the femoral tunnels (p=0.007). To our knowledge, this novel, semi-automated 3D-computed tomography image processing method has shown to yield highly reproducible results for the measurement of bone tunnel diameter and area. This series showed a significantly higher amount of tunnel widening observed in the allograft group at one-year follow-up. Level II, Prospective comparative study. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Quantum tunneling time

    International Nuclear Information System (INIS)

    Wang, Z.S.; Lai, C.H.; Oh, C.H.; Kwek, L.C.

    2004-01-01

    We present a calculation of quantum tunneling time based on the transition duration of wave peak from one side of a barrier to the other. In our formulation, the tunneling time comprises a real and an imaginary part. The real part is an extension of the phase tunneling time with quantum corrections whereas the imaginary time is associated with energy derivatives of the probability amplitudes

  17. Josephson tunneling and nanosystems

    OpenAIRE

    Ovchinnikov, Yurii; Kresin, Vladimir

    2010-01-01

    Josephson tunneling between nanoclusters is analyzed. The discrete nature of the electronic energy spectra, including their shell ordering, is explicitly taken into account. The treatment considers the two distinct cases of resonant and non-resonant tunneling. It is demonstrated that the current density greatly exceeds the value discussed in the conventional theory. Nanoparticles are shown to be promising building blocks for nanomaterials-based tunneling networks.

  18. About tunnelling times

    International Nuclear Information System (INIS)

    Olkhovsky, V.S.; Recami, E.

    1991-08-01

    In this paper, first we critically analyse the main theoretical definitions and calculations of the sub-barrier tunnelling and reflection times. Secondly, we propose a new, physically sensible definition of such durations, on the basis of a recent general formalism (already tested for other types of quantum collisions). At last, we discuss some results regarding temporal evolution of the tunnelling processes, and in particular the ''particle'' speed during tunnelling. (author). 36 refs, 1 fig

  19. Energy Tunneling Behavior in Geometrically Separated Wave Guides

    Directory of Open Access Journals (Sweden)

    M. Omar

    2017-10-01

    Full Text Available In this paper, characteristics of energy tunneling channel between the waveguides geometrically separated by a coaxial cable are studied.  The novel aspect of design is use of coaxial channel to connect the waveguides while maintaining the energy tunneling phenomena. As anticipated the tunneling frequency depends upon the length of wire inside the waveguide and the length of the coaxial cable. The tunneling frequency also depends upon the dielectric constant of the material inside the waveguide and coaxial cable.  At tunneling frequency the field strength (E and H in the channel is extremely high, making the channel extremely sensitive to small change in permittivity of dielectric occupying the channel.  The advantage of the proposed design is, its ability to tune to desired tunneling frequency just by changing the length of the coaxial cable without the need to redesign the waveguide height to accommodate the long tunneling wires. This structure can be used as dielectric sensor both for solid or liquid dielectrics just by placing the sample in coaxial cable cavity, contrary to previously report work where the sample has to be placed inside the waveguide.

  20. Selective arteriography in femoral head fractures

    Energy Technology Data Exchange (ETDEWEB)

    Mannella, P; Galeotti, R; Borrelli, M; Benea, G; Massari, L; Chiarelli, G M

    1986-01-01

    The choice between conservative and radical operation in case of femoral neck fractures is very important because it is the determining factor for a successfull therapy. In case of epiphysial necrosis, an endoprosthesis as well as an osteosynthesis will be carried out. Selective arteriography of the medical circumflex artery represents the most reliable study to establish, immediately after the fractures, the possible presence of a post-traumatic ischemic necrosis. Angiography, as a reliable diagnostic tool, has to be carried out in the most selective way and needs the image subtraction technique. The authors report their preliminary results on the reliability of angiography in the femoral epiphyseal ischemic necrosis diagnosed by comparing the results of angiography with the wood light test carried out on the surgically removed femoral head. 18 refs.

  1. 99mTc-MDP scintigraphy of femoral head necrosis following femoral neck fracture

    International Nuclear Information System (INIS)

    Lee, Soon Jin; Lee, Jun Hyung; Kim, Eun Kyung; Lee, Sun Wha; Kim, Soon Yong

    1985-01-01

    Secondary ischemic necrosis of femoral head due to loss of blood supply following to femoral neck fracture is well known. The regional distribution of bone-seeking radiopharmaceuricals in the skeleton can depend on a number of factors, but bone blood flow is a major physiological determinant of regional skeletal uptake of Tc-99m polyphosphate and bone imaging may thus be used for the evaluation of vascularity of the femoral head. The authors made a comparative study of scintigraphic findings and operative findings of 28 cases of femoral neck fracture treated at Kyung Hee University Hospital from April 1980 to May 1984. The results were as follows: 1. In 16 cases of proven avascular necorsis of femoral head, scintigraphy showed absent or decreased activity in 14 cases (87.5%), while radiography showed increased density in 10 cases (62.5%). 2. In 12 cases of proven vital femoral head, scintigraphy showed increased activity in 9 cases (75%) and radiography showed decreased density in 9 cases (75%). 3. 99mTc-MDP scintigraphy was an excellent and useful method for assessing bone vitality of femoral head

  2. {sup 99m}Tc-MDP scintigraphy of femoral head necrosis following femoral neck fracture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soon Jin; Lee, Jun Hyung; Kim, Eun Kyung; Lee, Sun Wha; Kim, Soon Yong [Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

    1985-02-15

    Secondary ischemic necrosis of femoral head due to loss of blood supply following to femoral neck fracture is well known. The regional distribution of bone-seeking radiopharmaceuricals in the skeleton can depend on a number of factors, but bone blood flow is a major physiological determinant of regional skeletal uptake of Tc-99m polyphosphate and bone imaging may thus be used for the evaluation of vascularity of the femoral head. The authors made a comparative study of scintigraphic findings and operative findings of 28 cases of femoral neck fracture treated at Kyung Hee University Hospital from April 1980 to May 1984. The results were as follows: 1. In 16 cases of proven avascular necorsis of femoral head, scintigraphy showed absent or decreased activity in 14 cases (87.5%), while radiography showed increased density in 10 cases (62.5%). 2. In 12 cases of proven vital femoral head, scintigraphy showed increased activity in 9 cases (75%) and radiography showed decreased density in 9 cases (75%). 3. 99mTc-MDP scintigraphy was an excellent and useful method for assessing bone vitality of femoral head.

  3. Microsystem Aeromechanics Wind Tunnel

    Data.gov (United States)

    Federal Laboratory Consortium — The Microsystem Aeromechanics Wind Tunnel advances the study of fundamental flow physics relevant to micro air vehicle (MAV) flight and assesses vehicle performance...

  4. frequency of ipsilateral femoral neck fractures in patients

    African Journals Online (AJOL)

    Background: Ipsilateral associated femoral neck and shaft fractures are reported to occur in 2.5-6% of all femoral shaft ... nailing of the shaft fracture, which makes treatment of the neck ... chest, spine), while the other had maxillofacial injuries.

  5. Femoral component loosening after hip resurfacing arthroplasty

    International Nuclear Information System (INIS)

    Zustin, Jozef; Sauter, Guido; Hahn, Michael; Morlock, Michael M.; Ruether, Wolfgang; Amling, Michael

    2010-01-01

    Before the re-introduction of the current generation of total hip resurfacing arthroplasty, component loosening and osteolysis were of great concern to the orthopaedic community. Early, mid- and long-term clinical results are encouraging, but component loosening still exists. Macroscopic, contact radiographic and histopathological analyses after undecalcified preparation of bone tissue specimens were performed. To investigate the frequency and morphological patterns of the loosening of the femoral component, we analysed a series of 190 retrieved femoral remnants that were revised for aseptic failures. Thirty-five (18.4%) hips were revised for clinical and/or radiographic loosening of the femoral component. Pseudoarthrosis (n = 17; median in situ time: 16 weeks, interquartile range [IQR]: 9 to 34), collapsed osteonecrosis (n = 5; median in situ time: 79 weeks, IQR: 63 to 97), cement-socket debonding (n = 3; median in situ time: 89 weeks, IQR: 54 to 97) and at later follow-up bone-cement loosening (n = 10; median in situ time: 175 weeks; IQR 112 to 198; p =0.005) were distinct patterns of the femoral remnant-implant loosening. Fibrocartilaginous metaplasia of interface bone trabeculae (n = 38; median in situ time: 61 weeks, IQR: 32 to 138) was strongly associated with femoral component loosening (p = 0.009). Both the trabecular hyperosteoidosis (n = 32; median in situ time: 71 weeks, IQR 50 to 129) and excessive intraosseous lymphocyte infiltration (n = 12; median in situ time: 75 weeks, IQR 51 to 98) at the bone-cement interface correlated strongly with fibrocartilaginous metaplasia (p = 0.001 and p = 0.016 respectively) and all three lesions were associated with the female gender (p = 0.021, p = 0.009, and p = 0.051). Femoral component loosening at early follow-up was mostly caused by pathological changes of the femoral remnant bone tissue: pseudoarthrosis and collapsed osteonecrosis. Fibrocartilaginous metaplasia was frequently observed in hips with femoral

  6. Production of oscillatory flow in wind tunnels

    Science.gov (United States)

    Al-Asmi, K.; Castro, I. P.

    1993-06-01

    A method for producing oscillatory flow in open-circuit wind tunnels driven by centrifugal fans is described. Performance characteristics of a new device installed on two such tunnels of greatly differing size are presented. It is shown that sinusoidal variations of the working section flow, having peak-to-peak amplitudes up to at least 30 percent of the mean flow speed and frequencies up to, typically, that corresponding to the acoustic quarter-wave-length frequency determined by the tunnel size, can be obtained with negligible harmonic distortion or acoustic noise difficulties. A brief review of the various methods that have been used previously is included, and the advantages and disadvantages of these different techniques are highlighted. The present technique seems to represent a significant improvement over many of them.

  7. A retrospective review of bone tunnel enlargement after anterior cruciate ligament reconstruction with hamstring tendons fixed with a metal round cannulated interference screw in the femur.

    Science.gov (United States)

    Kobayashi, Masahiko; Nakagawa, Yasuaki; Suzuki, Takashi; Okudaira, Shuzo; Nakamura, Takashi

    2006-10-01

    To assess bone tunnel enlargement after anterior cruciate ligament (ACL) reconstruction with the use of hamstring tendons fixed with a round cannulated interference (RCI) screw in the femur. A consecutive series of 30 ACL reconstructions performed with hamstring tendons fixed with an RCI screw in the femur and with staples via Leeds-Keio ligament in the tibia was retrospectively reviewed. The clinical outcome was evaluated through the Lysholm score. Anterior instability was tested by Telos-SE (Telos Japan, Tokyo, Japan) measurement. The location and angle of each femoral and tibial tunnel were measured with the use of plain radiographs, and bone tunnel enlargement greater than 2 mm detected any time 3, 6, 12, and 24 months postoperatively was defined as positive. Each factor (location and angle of the tunnels, sex, affected side, age, Lysholm score, and Telos-SE measurement) was compared between enlarged and nonenlarged groups. Positive enlargement of the bone tunnel (>2.0 mm) was observed in 36.7% (11 of 30) on the femoral side and 33.3% (10 of 30) on the tibial side, and in 6 knees of both sides. Half of patients (15 of 30) had an enlarged tunnel on the femoral or the tibial side until 1 year postoperatively. In most cases, enlargement reached maximum at 6 months postoperatively. Female patients tended to have an enlarged tunnel, especially on the femoral side (P < .05). Tunnel enlargement was not correlated with location and angle of the tunnels. Moreover, no difference was found in Lysholm score and Telos-SE measurement between enlarged and nonenlarged groups, although the nonenlarged group tended to exhibit higher Lysholm score and lesser instability. Bone tunnel enlargement of the femoral or tibial side was observed in half of patients (6 in both sides, 5 only in the femur, and 4 only in the tibia) after ACL reconstruction was performed with a hamstring tendon fixed with an RCI screw. Female patients had a greater chance for enlargement of the femoral tunnel

  8. Inferior tendon graft to bone tunnel healing at the tibia compared to that at the femur after anterior cruciate ligament reconstruction

    International Nuclear Information System (INIS)

    Lui, P.P.Y.; Ho, G.; Shum, W.T.; Lee, Y.W.; Ho, P.Y.; Lo, W.N.; Lo, C.K.

    2010-01-01

    Tunnel widening after anterior cruciate ligament (ACL) reconstruction (ACLR) is commonly reported without a clear understanding of the mechanism. This study aimed to quantify the spatiotemporal change of the newly formed bone mass, bone tunnel diameter, and area along both bone tunnels using micro-computed tomography (μCT) and correlated the result with histology. ACLR was performed in 24 rabbits. At baseline and weeks 2, 6, and 12, the juxta-articular, middle, and exit segments of both tunnels were harvested for μCT and histological evaluation. μCT and histology revealed significant bone tunnel and graft-bone tunnel healing, respectively, only at week 6 after reconstruction. Despite this, the mean tunnel diameter and area remained relatively unchanged with time. The newly formed bone mass [new bone volume/total bone volume (BV/TV) ratio] and its bone mineral density (BMD) were both higher, whereas the mean tunnel diameter and area were significantly smaller at the femoral tunnel compared to those at the tibial tunnel at weeks 6 and 12 and at week 12, respectively. These were consistent with histological findings, which showed inferior graft remodeling and integration at the tibial tunnel at weeks 6 and 12. The BV/TV increased, whereas the mean tunnel diameter and area decreased toward the exit segment of both tunnels. However, whereas better histological healing occurred at the femoral exit segment, poorer graft remodeling and Sharpey's fiber formation occurred at the tibial exit segment. Poor healing was observed during the initial 6 weeks, particularly that of the tibia, after ACLR. Bone resorption was rapid during healing, resulting in unchanged tunnel diameter and area with time. (author)

  9. Experience in design and construction of the Log tunnel

    Directory of Open Access Journals (Sweden)

    Jovičić Vojkan

    2017-09-01

    Full Text Available A twin highway Log tunnel is a part of a new motorway connection between Maribor and Zagreb, section Draženci-Gruškovje, which is located towards the border crossing between Slovenia and Croatia. The tunnel is currently under construction, and only the excavation works have been completed during the writing of this paper. The terrain in the area of the Log tunnel is diverse, and the route of the highway in its vicinity is characterised by deep excavations, bridges or viaducts. The Log tunnel is approximately 250 m long, partly constructed as a gallery. The geological conditions are dominated by Miocene base rock, featuring layers of well-connected clastic rocks, which are covered by diluvium clays, silts, sands and gravels of different thicknesses. Due to the short length of the tunnel, the usual separation of the motorway route to the left and the right tunnel axes was not carried out. Thus, the tunnel was constructed with an intermediate pillar and was designed as a three-lane tunnel, including the stopping lane. The construction of the tunnel was carried out using the New Austrian tunnelling method (NATM, in which the central adit was excavated first and the intermediate pillar was constructed within it. The excavation of the main tubes followed and was divided into the top heading, bench and the invert, enabling the intermediate pillar to take the load off the top heading of both tubes. The secondary lining of the tunnel is currently under construction. The experience of the tunnel construction gathered so far is presented in the paper. The main emphasis is on the construction of the intermediate pillar, which had to take the significant and asymmetrical ground load.

  10. Experience in design and construction of the Log tunnel

    Science.gov (United States)

    Jovičić, Vojkan; Goleš, Niko; Tori, Matija; Peternel, Miha; Vajović, Stanojle; Muhić, Elvir

    2017-09-01

    A twin highway Log tunnel is a part of a new motorway connection between Maribor and Zagreb, section Draženci-Gru\\vskovje, which is located towards the border crossing between Slovenia and Croatia. The tunnel is currently under construction, and only the excavation works have been completed during the writing of this paper. The terrain in the area of the Log tunnel is diverse, and the route of the highway in its vicinity is characterised by deep excavations, bridges or viaducts. The Log tunnel is approximately 250 m long, partly constructed as a gallery. The geological conditions are dominated by Miocene base rock, featuring layers of well-connected clastic rocks, which are covered by diluvium clays, silts, sands and gravels of different thicknesses. Due to the short length of the tunnel, the usual separation of the motorway route to the left and the right tunnel axes was not carried out. Thus, the tunnel was constructed with an intermediate pillar and was designed as a three-lane tunnel, including the stopping lane. The construction of the tunnel was carried out using the New Austrian tunnelling method (NATM), in which the central adit was excavated first and the intermediate pillar was constructed within it. The excavation of the main tubes followed and was divided into the top heading, bench and the invert, enabling the intermediate pillar to take the load off the top heading of both tubes. The secondary lining of the tunnel is currently under construction. The experience of the tunnel construction gathered so far is presented in the paper. The main emphasis is on the construction of the intermediate pillar, which had to take the significant and asymmetrical ground load.

  11. Trunnion Failure of the Recalled Low Friction Ion Treatment Cobalt Chromium Alloy Femoral Head.

    Science.gov (United States)

    Urish, Kenneth L; Hamlin, Brian R; Plakseychuk, Anton Y; Levison, Timothy J; Higgs, Genymphas B; Kurtz, Steven M; DiGioia, Anthony M

    2017-09-01

    Gross trunnion failure (GTF) is a rare complication in total hip arthroplasty (THA) reported across a range of manufacturers. Specific lots of the Stryker low friction ion treatment (LFIT) anatomic cobalt chromium alloy (CoCr) V40 femoral head were recalled in August 2016. In part, the recall was based out of concerns for disassociation of the femoral head from the stem and GTF. We report on 28 patients (30 implants) with either GTF (n = 18) or head-neck taper corrosion (n = 12) of the LFIT CoCr femoral head and the Accolade titanium-molybdenum-zirconium-iron alloy femoral stems. All these cases were associated with adverse local tissue reactions requiring revision of the THA. In our series, a conservative estimate of the incidence of failure was 4.7% (n = 636 total implanted) at 8.0 ± 1.4 years from the index procedure. Failures were associated with a high-offset 127° femoral stem neck angle and increased neck lengths; 43.3% (13 of 30) of the observed failures included implant sizes outside the voluntary recall (27.8% [5 of 18] of the GTF and 75.0% [8 of 12] of the taper corrosion cases). Serum cobalt and chromium levels were elevated (cobalt: 8.4 ± 7.0 μg/mL; chromium: 3.4 ± 3.3 μ/L; cobalt/chromium ratio: 3.7). The metal artifact reduction sequence magnetic resonance imaging demonstrated large cystic fluid collections typical with adverse local tissue reactions. During revision, a pseudotumor was observed in all cases. Pathology suggested a chronic inflammatory response. Impending GTF could be diagnosed based on aspiration of black synovial fluid and an oblique femoral head as compared with the neck taper on radiographs. In our series of the recalled LFIT CoCr femoral head, the risk of impending GTF or head-neck taper corrosion should be considered as a potential diagnosis in a painful LFIT femoral head and Accolade titanium-molybdenum-zirconium-iron alloy THA with unknown etiology. Almost half of the failures we observed included sizes outside of the

  12. Scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Binnig, G.; Rohrer, H.

    1983-01-01

    Based on vacuum tunneling, a novel type of microscope, the scanning tunneling microscope (STM) was developed. It has an unprecedented resolution in real space on an atomic scale. The authors review the important technical features, illustrate the power of the STM for surface topographies and discuss its potential in other areas of science and technology. (Auth.)

  13. Electron tunneling in chemistry

    International Nuclear Information System (INIS)

    Zamaraev, K.I.; Khajrutdinov, R.F.; Zhdanov, V.P.; Molin, Yu.N.

    1985-01-01

    Results of experimental and theoretical investigations are outlined systematically on electron tunnelling in chemical reactions. Mechanism of electron transport to great distances is shown to be characteristic to chemical compounds of a wide range. The function of tunnel reactions is discussed for various fields of chemistry, including radiation chemistry, electrochemistry, chemistry of solids, chemistry of surface and catalysis

  14. Femoral Component External Rotation Affects Knee Biomechanics: A Computational Model of Posterior-stabilized TKA.

    Science.gov (United States)

    Kia, Mohammad; Wright, Timothy M; Cross, Michael B; Mayman, David J; Pearle, Andrew D; Sculco, Peter K; Westrich, Geoffrey H; Imhauser, Carl W

    2018-01-01

    The correct amount of external rotation of the femoral component during TKA is controversial because the resulting changes in biomechanical knee function associated with varying degrees of femoral component rotation are not well understood. We addressed this question using a computational model, which allowed us to isolate the biomechanical impact of geometric factors including bony shapes, location of ligament insertions, and implant size across three different knees after posterior-stabilized (PS) TKA. Using a computational model of the tibiofemoral joint, we asked: (1) Does external rotation unload the medial collateral ligament (MCL) and what is the effect on lateral collateral ligament tension? (2) How does external rotation alter tibiofemoral contact loads and kinematics? (3) Does 3° external rotation relative to the posterior condylar axis align the component to the surgical transepicondylar axis (sTEA) and what anatomic factors of the femoral condyle explain variations in maximum MCL tension among knees? We incorporated a PS TKA into a previously developed computational knee model applied to three neutrally aligned, nonarthritic, male cadaveric knees. The computational knee model was previously shown to corroborate coupled motions and ligament loading patterns of the native knee through a range of flexion. Implant geometries were virtually installed using hip-to-ankle CT scans through measured resection and anterior referencing surgical techniques. Collateral ligament properties were standardized across each knee model by defining stiffness and slack lengths based on the healthy population. The femoral component was externally rotated from 0° to 9° relative to the posterior condylar axis in 3° increments. At each increment, the knee was flexed under 500 N compression from 0° to 90° simulating an intraoperative examination. The computational model predicted collateral ligament forces, compartmental contact forces, and tibiofemoral internal/external and

  15. Angiographic analysis of avascular necrosis of a femoral head -selective angiography of medial femoral circumflex artery-

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Kyung Nam; Yoon, Yup; Lee, Sun Wha; Lim, Jae Hoon [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1991-07-15

    The degree of anatomical revascularization of a necrotic femoral head and traumatic hip would provide information about treatment and prognosis. The authors analyzed the vascular changes of femoral head among unilateral avascular necrosis, bilateral avascular necrosis, and traumatic hips. Forty - four patients with avascular necrosis and 19 patients with traumatic hips were examined by selective angiography of the medial femoral circumflex artery. In the traumatic hip cases, 12 (63%) showed occlusion, 2 (11%) hypertrophy of the capsular branches, and 5 ( 26 % ) were normal . In the avascular necrosis cases, 15 (25%) showed occlusion, 39 (67%) had hypertrophy of the capsular branches, and 4 (7%) had normal findings. Hypertrophy of the superior capsular branch of the medial femoral circumflex artery is more frequently observed in avascular necrosis than in traumatic hip. Bilateral avascular necrosis reveals more frequent incidences than unilateral cases. Selective angiography could help in the therapy plan and also provide information about the contralateral side.

  16. Angiographic analysis of avascular necrosis of a femoral head -selective angiography of medial femoral circumflex artery-

    International Nuclear Information System (INIS)

    Ryu, Kyung Nam; Yoon, Yup; Lee, Sun Wha; Lim, Jae Hoon

    1991-01-01

    The degree of anatomical revascularization of a necrotic femoral head and traumatic hip would provide information about treatment and prognosis. The authors analyzed the vascular changes of femoral head among unilateral avascular necrosis, bilateral avascular necrosis, and traumatic hips. Forty - four patients with avascular necrosis and 19 patients with traumatic hips were examined by selective angiography of the medial femoral circumflex artery. In the traumatic hip cases, 12 (63%) showed occlusion, 2 (11%) hypertrophy of the capsular branches, and 5 ( 26 % ) were normal . In the avascular necrosis cases, 15 (25%) showed occlusion, 39 (67%) had hypertrophy of the capsular branches, and 4 (7%) had normal findings. Hypertrophy of the superior capsular branch of the medial femoral circumflex artery is more frequently observed in avascular necrosis than in traumatic hip. Bilateral avascular necrosis reveals more frequent incidences than unilateral cases. Selective angiography could help in the therapy plan and also provide information about the contralateral side

  17. Subintimal angioplasty for the treatment of long segment occlusion of superficial femoral artery: the midterm results

    International Nuclear Information System (INIS)

    Lou Wensheng; Gu Jianping; He Xu; Chen Liang; Chen Guoping; Su Haobo; Song Jinhua; Wang Tao; Xu Ke

    2011-01-01

    Objective: To discuss the clinical value of subintimal angioplasty in treating long segment occlusion of superficial femoral artery and to observe its midterm results. Methods: Subintimal angioplasty was performed in 45 patients with long segment occlusion of superficial femoral artery, whose clinical presentation was intermittent claudication or critical limb ischemia. The primary patency, limb salvage and factors influencing long-term patency were observed, and the clinical data were analyzed. Results: Of the total 45 cases, the subintimal angioplasty was successfully accomplished in 43. The success rate of antegrade approach technique via the superficial femoral artery was 80% (n=36), the occlusion was recanalized by using retrograde approach technique via ipsilateral popliteal artery in 7 case. The total technical success rate was 95.6%. The primary patency in 43 successful cases at 6, 12, 24 and 36 months was 85.7%, 69.0% 57.3% and 50.9%, respectively. No statistically significant difference in primary patency existed between the group of intermittent claudication and the group of critical limb ischemia (P>0.05). Statistically significant prediction factors for primary patency included the number of the run off vessels below the knee and the length of the occlusion (P<0.05). Conclusion: Subintimal angioplasty is an effective procedure for the treatment of long segment occlusions of superficial femoral artery with satisfactory mid-term results. (authors)

  18. Fibrous dysplasia of the femoral neck

    International Nuclear Information System (INIS)

    Savage, P.E.; Stoker, D.J.

    1984-01-01

    Fibrous dysplasia of the femur is usually observed in the intertrochanteric region. It is rarely confined to the femoral neck. We present four cases illustrating the radiographic appearance and spectrum of this condition which all showed the relatively lucent variety of fibrous dysplasia with varying degrees of expansion and surrounding sclerosis. The natural history of this condition is discussed. (orig.)

  19. Femoral Hernia At Mulago Hospital, Uganda

    African Journals Online (AJOL)

    user

    2004-12-02

    Dec 2, 2004 ... consecutive patients operated for femoral hernia over a period of twelve months. Results: There were ... The age ranged from 42 years to 70 years old with a mean of 54.6 years old. All the .... cholecystectomy. At this point in ...

  20. Radiation-induced femoral head necrosis

    African Journals Online (AJOL)

    2011-03-25

    Mar 25, 2011 ... had open medial menisectomy of the left knee following medial meniscal tear ... postoperative recovery and mobilised full weight-bearing immediately [Figure 6]. ... obtained from the oncologists at the time of this review), and there was a ... previous trauma such as femoral neck fracture, Gaucher's disease ...

  1. Transvenous liver biopsy via the femoral vein

    International Nuclear Information System (INIS)

    Khosa, F.; McNulty, J.G.; Hickey, N.; O'Brien, P.; Tobin, A.; Noonan, N.; Ryan, B.; Keeling, P.W.N.; Kelleher, D.P.; McDonald, G.S.A.

    2003-01-01

    AIM: To study the safety, effectiveness and diagnostic value of transvenous forceps biopsy of the liver in 54 patients with coagulopathy, gross ascites or morbid obesity and suspected liver disease in whom percutaneous liver biopsy was contraindicated. MATERIAL AND METHODS: Forceps biopsy of the liver via the femoral vein was attempted in 54 adult patients with advanced liver disease of unknown aetiology who had coagulation disorders (41 cases), gross ascites (11 cases) or morbid obesity (two cases). In each patient two to six biopsies (average four) were taken using a radial jaw forceps inserted via the right or left femoral vein. RESULTS: The procedure was successful in 53 cases. Hepatic vein catheterization failed in one patient. Adequate liver tissue for diagnosis was obtained in 84% of cases. One patient developed delayed haemorrhage at 12 h from a capsular leak that was undetected during the biopsy procedure. This patient required blood transfusions and laparotomy to control bleeding. There were no deaths in the 53 patients studied. Transient minor chest and shoulder pain was encountered during sheath insertion into a hepatic vein in 23 patients. Three patients developed a femoral vein haematoma, which resolved with conservative treatment. CONCLUSION: Transvenous liver biopsy via the femoral vein is another safe, effective, simple alternative technique of biopsy when the percutaneous route is contraindicated

  2. Postmortem Femoral Blood Concentrations of Risperidone

    DEFF Research Database (Denmark)

    Linnet, Kristian; Johansen, Sys Stybe

    2014-01-01

    Postmortem femoral blood concentrations of the antipsychotic drug risperidone and the active metabolite 9-hydroxyrisperidone were determined by an achiral LC-MS/MS method in 38 cases. The cause of death was classified as unrelated to risperidone in 30 cases, in which the sum of the concentration ...

  3. Femoral Prosthesis Infection by Rhodotorula mucilaginosa▿

    Science.gov (United States)

    Savini, Vincenzo; Sozio, Federica; Catavitello, Chiara; Talia, Marzia; Manna, Assunta; Febbo, Fabio; Balbinot, Andrea; Di Bonaventura, Giovanni; Piccolomini, Raffaele; Parruti, Giustino; D'Antonio, Domenico

    2008-01-01

    This case report is a case history of a femoral prosthesis infection caused by Rhodotorula mucilaginosa in a human immunodeficiency virus patient. Though the pathogenicity of this organism for bone tissue has been previously reported, this is the first reported case of an orthopedic prosthesis infection by this species of the genus Rhodotorula. PMID:18753353

  4. Aseptic necrosis of femoral head complicating thalassemia

    International Nuclear Information System (INIS)

    Orzincolo, C.; Castaldi, G.; Scutellary, P.N.; Bariani, L.; Pinca, A.

    1986-01-01

    Aseptic necrosis of the femoral head is described in 4 patients, selected from 280 patients with homozygous β-thalassemia (Cooley anemia). The incidence of the complication appears to be very high (14.5per mille) in thalassemia, compared to the general population. The possible mechanism are discussed. (orig.)

  5. Tunnel fire dynamics

    CERN Document Server

    Ingason, Haukur; Lönnermark, Anders

    2015-01-01

    This book covers a wide range of issues in fire safety engineering in tunnels, describes the phenomena related to tunnel fire dynamics, presents state-of-the-art research, and gives detailed solutions to these major issues. Examples for calculations are provided. The aim is to significantly improve the understanding of fire safety engineering in tunnels. Chapters on fuel and ventilation control, combustion products, gas temperatures, heat fluxes, smoke stratification, visibility, tenability, design fire curves, heat release, fire suppression and detection, CFD modeling, and scaling techniques all equip readers to create their own fire safety plans for tunnels. This book should be purchased by any engineer or public official with responsibility for tunnels. It would also be of interest to many fire protection engineers as an application of evolving technical principles of fire safety.

  6. New Knowledge of tunneling from photonic experiments

    International Nuclear Information System (INIS)

    Nimtz, G.

    1997-01-01

    Photonic experiments have shown, that the propagation of evanescent (tunneling) modes can proceed at speeds faster than the velocity of light in vacuum (superluminal). The superluminal velocities include signal and energy propagation. The analogy between the classical Helmholtz equation and the quantum mechanical Schroedinger equation was quantitatively proved in classical photonic experiments. The Hartman effect, i.e. the prediction that the tunneling time is independent of the barrier length was for the first time evidenced in a photonic analogous tunneling experiment by Enders and Nimtz. It is also shown, that the resonant state life time is not determined by the barrier traversal time. For electronic tunneling devices it follows, that the quantum mechanical phase time calculations indeed deliver the relevant intrinsic tunneling time and consequently allow to predict the dynamical specification of a device. The present theoretical descriptions of the propagation of evanescent modes is not fully compatible with the experimental situation. Superluminal signal and energy transport has been measured, and this has to be properly analyzed. May the advanced field solutions help to obtain a satisfactory theoretical description of the recent experimental results of the propagation of evanescent modes? (author)

  7. Lateral femoral traction pin entry: risk to the femoral artery and other medial neurovascular structures

    Directory of Open Access Journals (Sweden)

    Appleton Paul

    2010-01-01

    Full Text Available Abstract Background Femoral skeletal traction assists in the reduction and transient stabilization of pelvic, acetabular, hip, and femoral fractures when splinting is ineffective. Traditional teaching has recommended a medial entry site for insertion of the traction pin in order to minimize injury to the femoral artery as it passes through Hunter's canal. The present anatomical study evaluates the risk to the femoral artery and other medial neurovascular structures using a lateral entry approach. Methods Six embalmed cadavers (twelve femurs were obtained for dissection. Steinman pins were drilled from lateral to medial at the level of the superior pole of the patella, at 2 cm, and at 4 cm proximal to this point. Medial superficial dissection was then performed to identify the saphenous nerve, the superior medial geniculate artery, the adductor hiatus, the tendinous insertion of the adductor magnus and the femoral artery. Measurements localizing these anatomic structures relative to the pins were obtained. Results The femoral artery was relatively safe and was no closer than 29.6 mm (mean from any of the three Steinman pins. The superior medial geniculate artery was the medial structure at most risk. Conclusions Lateral femoral traction pin entry is a safe procedure with minimal risk to the saphenous nerve and femoral artery. Of the structures examined, only the superior medial geniculate artery is at a risk of iatrogenic injury due to its position. The incidence of such injury in clinical practice and its clinical significance is not known. Lateral insertion facilitates traction pin placement since it minimizes the need to move the contralateral extremity out of the way of the drilling equipment or the need to elevate or externally rotate the injured extremity relative to the contralateral extremity.

  8. Preoperative virtual reduction reduces femoral malrotation in the treatment of bilateral femoral shaft fractures.

    Science.gov (United States)

    Omar, Mohamed; Suero, Eduardo M; Hawi, Nael; Decker, Sebastian; Krettek, Christian; Citak, Musa

    2015-10-01

    In bilateral femoral shaft fractures, significant malrotation (>15°) occurs in about 40 % of cases after intramedullary nailing. Most of the methods that provide rotational control during surgery are based on a comparison to the intact femur and, thus, not applicable for bilateral fractures. In this study, we evaluated if preoperative virtual reduction can help improving rotational alignment in patients with bilateral femoral shaft fractures. Seven patients with bilateral femoral shaft fractures were initially treated with external fixation of both femurs. After obtaining a CT scan of both legs, the fractures were reduced virtually using the software program VoXim®, and the amount and direction of rotational correction were calculated. Subsequently, the patients were treated by antegrade femoral nailing and rotation was corrected to the preoperatively calculated amount. After external fixation, the mean rotational difference between both legs was 15.0° ± 10.2°. Four out of seven patients had a significant malrotation over 15°. Following virtual reduction, the mean rotational difference between both legs was 2.1° ± 1.2°. After intramedullary nailing, no case of malrotation occurred and the mean rotational difference was 6.1° ± 2.8°. Preoperative virtual reduction allows determining the pretraumatic femoral antetorsion and provided useful information for the definitive treatment of bilateral femoral shaft fractures. We believe that this procedure is worth being implemented in the clinical workflow to avoid malrotation after intramedullary nailing.

  9. Femoral neck fracture following groin irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Grigsby, Perry W; Roberts, Heidi L; Perez, Carlos A

    1995-04-30

    Purpose: The incidence and risk factors are evaluated for femoral neck fracture following groin irradiation for gynecologic malignancies. Methods and Materials: The radiation therapy records of 1313 patients with advanced and recurrent cancer of the vagina, vulva, cervix, and endometrium, treated at the Mallinckrodt Institute of Radiology from 1954 to 1992, were reviewed. Median follow-up was 12.7 years. From this group, 207 patients were identified who received irradiation to the pelvis and groins with anterposterior-posterior anterior (AP-PA), 18 MV photons. Data were reviewed regarding irradiation dose to the femoral neck and other presumed risk factors including age, primary site, stage, groin node status, menopausal status, estrogen use, cigarette use, alcohol consumption, and osteoporosis. Results: The per-patient incidence of femoral neck fracture was 4.8% (10 out of 207). Four patients developed bilateral fractures. However, the cumulative actuarial incidence of fracture was 11% at 5 years and 15% at 10 years. Cox multivariate analysis of age, weight, and irradiation dose showed that only irradiation dose may be important to developing fracture. Step-wise logistic regression of presumed prognostic factors revealed that only cigarette use and x-ray evidence of osteoporosis prior to irradiation treatment were predictive of fracture. Conclusion: Femoral head fracture is a common complication of groin irradiation for gynecologic malignancies. Fracture in our database appears to be related to irradiation dose, cigarette use, and x-ray evidence of osteoporosis. Special attention should be given in treatment planning (i.e., shielding of femoral head/neck and use of appropriate electron beam energies for a portion of treatment) to reduce the incidence of this complication.

  10. Femoral neck fracture following groin irradiation

    International Nuclear Information System (INIS)

    Grigsby, Perry W.; Roberts, Heidi L.; Perez, Carlos A.

    1995-01-01

    Purpose: The incidence and risk factors are evaluated for femoral neck fracture following groin irradiation for gynecologic malignancies. Methods and Materials: The radiation therapy records of 1313 patients with advanced and recurrent cancer of the vagina, vulva, cervix, and endometrium, treated at the Mallinckrodt Institute of Radiology from 1954 to 1992, were reviewed. Median follow-up was 12.7 years. From this group, 207 patients were identified who received irradiation to the pelvis and groins with anterposterior-posterior anterior (AP-PA), 18 MV photons. Data were reviewed regarding irradiation dose to the femoral neck and other presumed risk factors including age, primary site, stage, groin node status, menopausal status, estrogen use, cigarette use, alcohol consumption, and osteoporosis. Results: The per-patient incidence of femoral neck fracture was 4.8% (10 out of 207). Four patients developed bilateral fractures. However, the cumulative actuarial incidence of fracture was 11% at 5 years and 15% at 10 years. Cox multivariate analysis of age, weight, and irradiation dose showed that only irradiation dose may be important to developing fracture. Step-wise logistic regression of presumed prognostic factors revealed that only cigarette use and x-ray evidence of osteoporosis prior to irradiation treatment were predictive of fracture. Conclusion: Femoral head fracture is a common complication of groin irradiation for gynecologic malignancies. Fracture in our database appears to be related to irradiation dose, cigarette use, and x-ray evidence of osteoporosis. Special attention should be given in treatment planning (i.e., shielding of femoral head/neck and use of appropriate electron beam energies for a portion of treatment) to reduce the incidence of this complication

  11. Single-magnon tunneling through a ferromagnetic nanochain

    International Nuclear Information System (INIS)

    Petrov, E.G.; Ostrovsky, V.

    2010-01-01

    Magnon transmission between ferromagnetic contacts coupled by a linear ferromagnetic chain is studied at the condition when the chain exhibits itself as a tunnel magnon transmitter. It is shown that dependently on magnon energy at the chain, a distant intercontact magnon transmission occurs either in resonant or off-resonant tunneling regime. In the first case, a transmission function depends weakly on the number of chain sites whereas at off-resonant regime the same function manifests an exponential drop with the chain length. Change of direction of external magnetic field in one of ferromagnetic contacts blocks a tunnel transmission of magnon.

  12. Review of evolution of tunnel position in anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Rayan, Faizal; Nanjayan, Shashi Kumar; Quah, Conal; Ramoutar, Darryl; Konan, Sujith; Haddad, Fares S

    2015-03-18

    Anterior cruciate ligament (ACL) rupture is one of the commonest knee sport injuries. The annual incidence of the ACL injury is between 100000-200000 in the United States. Worldwide around 400000 ACL reconstructions are performed in a year. The goal of ACL reconstruction is to restore the normal knee anatomy and kinesiology. The tibial and femoral tunnel placements are of primordial importance in achieving this outcome. Other factors that influence successful reconstruction are types of grafts, surgical techniques and rehabilitation programmes. A comprehensive understanding of ACL anatomy has led to the development of newer techniques supplemented by more robust biological and mechanical concepts. In this review we are mainly focussing on the evolution of tunnel placement in ACL reconstruction, focusing on three main categories, i.e., anatomical, biological and clinical outcomes. The importance of tunnel placement in the success of ACL reconstruction is well researched. Definite clinical and functional data is lacking to establish the superiority of the single or double bundle reconstruction technique. While there is a trend towards the use of anteromedial portals for femoral tunnel placement, their clinical superiority over trans-tibial tunnels is yet to be established.

  13. CT study of avascular necrosis of femoral head in adults

    International Nuclear Information System (INIS)

    Liu Jihua; Du Yuqing; Xu Aide

    2000-01-01

    Objective: To study the early and new CT signs of avascular necrosis of femoral head in adults. Methods: The CT scans of 127 cases with this condition were analyzed. Results: There were 90 hip joints with femoral head normal in shape, including 67 femoral heads with only high-density sclerosis and 23 ones with high-density and low-density areas. In 111 hip joints, the femoral head was depressed and manifested purely high-density sclerosis in 25 and mixed-density areas in 86. Air-filled cysts appeared in 43 femoral heads. In follow-up cases, the changes in shape and density of femoral head followed some rules. Conclusion: Purely high-density sclerosis is an early sign and is of great diagnostic value combined with its special shape. Air in femoral heads is also a sign of the disease

  14. Ultrafast scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  15. Tunnel magnetoresistance in alumina, magnesia and composite tunnel barrier magnetic tunnel junctions

    International Nuclear Information System (INIS)

    Schebaum, Oliver; Drewello, Volker; Auge, Alexander; Reiss, Guenter; Muenzenberg, Markus; Schuhmann, Henning; Seibt, Michael; Thomas, Andy

    2011-01-01

    Using magnetron sputtering, we have prepared Co-Fe-B/tunnel barrier/Co-Fe-B magnetic tunnel junctions with tunnel barriers consisting of alumina, magnesia, and magnesia-alumina bilayer systems. The highest tunnel magnetoresistance ratios we found were 73% for alumina and 323% for magnesia-based tunnel junctions. Additionally, tunnel junctions with a unified layer stack were prepared for the three different barriers. In these systems, the tunnel magnetoresistance ratios at optimum annealing temperatures were found to be 65% for alumina, 173% for magnesia, and 78% for the composite tunnel barriers. The similar tunnel magnetoresistance ratios of the tunnel junctions containing alumina provide evidence that coherent tunneling is suppressed by the alumina layer in the composite tunnel barrier. - Research highlights: → Transport properties of Co-Fe-B/tunnel barrier/Co-Fe-B magnetic tunnel junctions. → Tunnel barrier consists of MgO, Al-Ox, or MgO/Al-Ox bilayer systems. → Limitation of TMR-ratio in composite barrier tunnel junctions to Al-Ox values. → Limitation indicates that Al-Ox layer is causing incoherent tunneling.

  16. Tunneling current between graphene layers

    OpenAIRE

    Poklonski, Nikolai A.; Siahlo, Andrei I.; Vyrko, Sergey A.; Popov, Andrey M.; Lozovik, Yurii E.

    2013-01-01

    The physical model that allows to calculate the values of the tunneling current be-tween graphene layers is proposed. The tunneling current according to the pro-posed model is proportional to the area of tunneling transition. The calculated value of tunneling conductivity is in qualitative agreement with experimental data.

  17. RITD – Wind tunnel testing

    Science.gov (United States)

    Haukka, Harri; Harri, Ari-Matti; Aleksashkin, Sergei; Koryanov, Valeri; Schmidt, Walter; Heilimo, Jyri; Finchenko, Valeri; Martynov, Maxim; Ponomarenko, Andrey; Kazakovtsev, Victor; Arruego, Ignazio

    2015-04-01

    An atmospheric re-entry and descent and landing system (EDLS) concept based on inflatable hypersonic decelerator techniques is highly promising for the Earth re-entry missions. We developed such EDLS for the Earth re-entry utilizing a concept that was originally developed for Mars. This EU-funded project is called RITD - Re-entry: Inflatable Technology Development - and it was to assess the bene¬fits of this technology when deploying small payloads from low Earth orbits to the surface of the Earth with modest costs. The principal goal was to assess and develope a preliminary EDLS design for the entire relevant range of aerodynamic regimes expected to be encountered in Earth's atmosphere during entry, descent and landing. The RITD entry and descent system utilizes an inflatable hypersonic decelerator. Development of such system requires a combination of wind tunnel tests and numerical simulations. This included wind tunnel tests both in transsonic and subsonic regimes. The principal aim of the wind tunnel tests was the determination of the RITD damping factors in the Earth atmosphere and recalculation of the results for the case of the vehicle descent in the Mars atmosphere. The RITD mock-up model used in the tests was in scale of 1:15 of the real-size vehicle as the dimensions were (midsection) diameter of 74.2 mm and length of 42 mm. For wind tunnel testing purposes the frontal part of the mock-up model body was manufactured by using a PolyJet 3D printing technology based on the light curing of liquid resin. The tail part of the mock-up model body was manufactured of M1 grade copper. The structure of the mock-up model placed th center of gravity in the same position as that of the real-size RITD. The wind tunnel test program included the defining of the damping factor at seven values of Mach numbers 0.85; 0.95; 1.10; 1.20; 1.25; 1.30 and 1.55 with the angle of attack ranging from 0 degree to 40 degrees with the step of 5 degrees. The damping characteristics of

  18. Vacuum phonon tunneling.

    Science.gov (United States)

    Altfeder, Igor; Voevodin, Andrey A; Roy, Ajit K

    2010-10-15

    Field-induced phonon tunneling, a previously unknown mechanism of interfacial thermal transport, has been revealed by ultrahigh vacuum inelastic scanning tunneling microscopy (STM). Using thermally broadened Fermi-Dirac distribution in the STM tip as in situ atomic-scale thermometer we found that thermal vibrations of the last tip atom are effectively transmitted to sample surface despite few angstroms wide vacuum gap. We show that phonon tunneling is driven by interfacial electric field and thermally vibrating image charges, and its rate is enhanced by surface electron-phonon interaction.

  19. Telomere Length and Mortality

    DEFF Research Database (Denmark)

    Kimura, Masayuki; Hjelmborg, Jacob V B; Gardner, Jeffrey P

    2008-01-01

    Leukocyte telomere length, representing the mean length of all telomeres in leukocytes, is ostensibly a bioindicator of human aging. The authors hypothesized that shorter telomeres might forecast imminent mortality in elderly people better than leukocyte telomere length. They performed mortality...

  20. Satisfactory Results of the Exeter Revision Femoral Stem Used for Primary Total Hip Arthroplasty.

    Science.gov (United States)

    Desy, Nicholas M; Johnson, Joshua D; Sierra, Rafael J

    2017-02-01

    The Exeter cemented femoral stem has demonstrated excellent clinical and radiographic outcomes as well as long-term survivorship free from aseptic loosening. A shorter revision stem (125 mm) with a 44 offset became available for the purpose of cement-in-cement revision situations. In certain cases, this shorter revision stem may be used for various primary total hip arthroplasties (THAs) where the standard length stem would require distally reaming the femoral canal. We sought to report on the early to midterm results of this specific stem when used for primary THA regarding (1) clinical and radiographic outcomes, (2) complications, and (3) survivorship. Twenty-nine patients (33 hips) underwent a hybrid THA using the smaller revision Exeter cemented femoral stem. Twenty-five patients (28 hips) had at least 2 years of follow-up and were assessed for clinical and radiographic outcomes. All 33 hips were included in the analysis of complications and survivorship. The Kaplan-Meier survivorship was performed using revision for all causes and for aseptic loosening as the end points. The average clinical follow-up was 4 years (range, 2-7). Harris Hip Scores improved from a mean preoperative value of 56 (range, 23-96) to 90 (range, 51-100) at the latest follow-up. All patients demonstrated superior cement mantles with no signs of loosening. One patient suffered a B2 periprosthetic fracture and 1 patient experienced 2 episodes of instability. The 5-year Kaplan-Meier survivorship was 96.7% for all causes of revision and was 100% using aseptic loosening as the end point. The shorter Exeter revision cemented femoral stem has favorable early to midterm clinical and radiographic outcomes when used for primary THA with a low complication rate and is a viable option in patients with narrow femoral canals where uncemented stem fixation is not desired. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

  2. Recanalization of superficial femoral artery by retrograde approach via popliteal artery

    International Nuclear Information System (INIS)

    Kim, Jae Kyu; Kim, Hyung Kil; Yun, Ung; Seo, Jeong Jin; Kang, Heoung Keun

    1995-01-01

    To recanalize the occlusive lesion of superficial femoral artery at origin site by retrograde approach via popliteal artery. 15 patients, who were poor surgical candidates due to coronary artery disease and who had severe occlusive lesion of superficial femoral artery close to its origin with good distal runoffs to popliteal artery, were selected. Patients were all men and range of age were from 53 years to 66 years (mean age: 63 years). Range of lesion length were from 15 cm to 30 cm (mean length: 22.4 cm). Localization of popliteal artery was done with Doppler stethoscope or 'road-map' DSA. The method of recanalization were transluminal endarterectomy catheter (TEC), TEC and angioplasty, thrombolysoangioplasty (TLA). Retrograde puncture of popliteal artery was done in 15 patients successfully. TEC and PTA was performed in 9 patients, TEC only in 2 patients, and TLA and PTA in 2 patients. During the follow-up period of 5 months to 2 years reocclusion did not occur in 10 patients except for 1 patient with poor cardiac output in whom it occurred 1 day later. Remained 4 patients were lost in follow up. Any neurologic or vascular complication did not occur. Retrograde approach of superficial femoral artery via popliteal artery in patients with difficult vascular intervention by common method provides a useful, alternative recanalization method

  3. Recanalization of superficial femoral artery by retrograde approach via popliteal artery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Kyu; Kim, Hyung Kil; Yun, Ung; Seo, Jeong Jin; Kang, Heoung Keun [Chonnam University Medical School, Kwangju (Korea, Republic of)

    1995-09-15

    To recanalize the occlusive lesion of superficial femoral artery at origin site by retrograde approach via popliteal artery. 15 patients, who were poor surgical candidates due to coronary artery disease and who had severe occlusive lesion of superficial femoral artery close to its origin with good distal runoffs to popliteal artery, were selected. Patients were all men and range of age were from 53 years to 66 years (mean age: 63 years). Range of lesion length were from 15 cm to 30 cm (mean length: 22.4 cm). Localization of popliteal artery was done with Doppler stethoscope or 'road-map' DSA. The method of recanalization were transluminal endarterectomy catheter (TEC), TEC and angioplasty, thrombolysoangioplasty (TLA). Retrograde puncture of popliteal artery was done in 15 patients successfully. TEC and PTA was performed in 9 patients, TEC only in 2 patients, and TLA and PTA in 2 patients. During the follow-up period of 5 months to 2 years reocclusion did not occur in 10 patients except for 1 patient with poor cardiac output in whom it occurred 1 day later. Remained 4 patients were lost in follow up. Any neurologic or vascular complication did not occur. Retrograde approach of superficial femoral artery via popliteal artery in patients with difficult vascular intervention by common method provides a useful, alternative recanalization method.

  4. Oscillations in a Forward-Facing Cavity Measured Using Laser-Differential Interferometry in a Hypersonic Quiet Tunnel

    Science.gov (United States)

    2007-12-11

    Boeing/AFOSR Mach-6 Quiet Tunnel BFL Back Focal Length xvi CCA Constant Current Anemometer EFL Effective Focal Length FFC Forward Facing Cavity LDI Laser...step in the nozzle throat. This tunnel is currently used for teaching as well as for research. Some years ago, a group of students separated the

  5. Quantum tunneling with friction

    Science.gov (United States)

    Tokieda, M.; Hagino, K.

    2017-05-01

    Using the phenomenological quantum friction models introduced by P. Caldirola [Nuovo Cimento 18, 393 (1941), 10.1007/BF02960144] and E. Kanai [Prog. Theor. Phys. 3, 440 (1948), 10.1143/ptp/3.4.440], M. D. Kostin [J. Chem. Phys. 57, 3589 (1972), 10.1063/1.1678812], and K. Albrecht [Phys. Lett. B 56, 127 (1975), 10.1016/0370-2693(75)90283-X], we study quantum tunneling of a one-dimensional potential in the presence of energy dissipation. To this end, we calculate the tunneling probability using a time-dependent wave-packet method. The friction reduces the tunneling probability. We show that the three models provide similar penetrabilities to each other, among which the Caldirola-Kanai model requires the least numerical effort. We also discuss the effect of energy dissipation on quantum tunneling in terms of barrier distributions.

  6. Wind Tunnel Testing Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — NASA Ames Research Center is pleased to offer the services of our premier wind tunnel facilities that have a broad range of proven testing capabilities to customers...

  7. INCAS TRISONIC WIND TUNNEL

    Directory of Open Access Journals (Sweden)

    Florin MUNTEANU

    2009-09-01

    Full Text Available The 1.2 m x 1.2 m Trisonic Blowdown Wind Tunnel is the largest of the experimental facilities at the National Institute for Aerospace Research - I.N.C.A.S. "Elie Carafoli", Bucharest, Romania. The tunnel has been designed by the Canadian company DSMA (now AIOLOS and since its commissioning in 1978 has performed high speed aerodynamic tests for more than 120 projects of aircraft, missiles and other objects among which the twin jet fighter IAR-93, the jet trainer IAR-99, the MIG-21 Lancer, the Polish jet fighter YRYDA and others. In the last years the wind tunnel has been used mostly for experimental research in European projects such as UFAST. The high flow quality parameters and the wide range of testing capabilities ensure the competitivity of the tunnel at an international level.

  8. The ISI Tunnel

    Science.gov (United States)

    1993-10-01

    DP /etc/tunnelvisa p zephyr dark -star TCP /etc/tunnelvisa p zephyr dak’star ICMP /etc/tunnelvisa p zephyr quark MDP /etc/tunnelvisa p zephyr quark ...drax-net-yp 128.9.32.2 1 route add quark -net-yp 128.9.32.3 1 route add vlsi-net-yp 128.9.32.4 1 route add darkstar-net-yp 128.9.32.3 1 route add rocky...TCP /etc/tunnel-visa p zephyr quark ICMP /etc/tunnel-visa p zephyr drax tTI)P /etc/tunnel-visa p zephyr drax TCP /etc/tunnel_visa p zephyr drax ICMP

  9. Wind Tunnel Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This ARDEC facility consists of subsonic, transonic, and supersonic wind tunnels to acquire aerodynamic data. Full-scale and sub-scale models of munitions are fitted...

  10. Water Tunnel Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NETL’s High-Pressure Water Tunnel Facility in Pittsburgh, PA, re-creates the conditions found 3,000 meters beneath the ocean’s surface, allowing scientists to study...

  11. Risk Factors and Clinical Evaluation of Superficial Femoral Artery Stent Fracture: Prote'ge'GPS Stent

    International Nuclear Information System (INIS)

    Lee, Da Un; Kim, Jae Kyu; Jung, Hye Doo; Huh, Tae Wook; Yim, Nam Yeol; Oh, Hyun jun; Choi, Soo Jin Na; Chang, Nam Kyu

    2010-01-01

    To evaluate the occurrence of superficial femoral artery stent fractures, the risk factors of stent fracture, and the relationship between fractures and clinical findings. Of the 38 patients who underwent treatment with Prote'ge'GPS stenting due to arterial occlusions on the superficial femoral artery, 17 also underwent a clinical analysis. Forty-three stents were inserted in the 17 superficial femoral arteries, ranging between 15 and 50 cm in length, with a mean treated length of 26.4 cm (15-50 cm). A fracture was evaluated by taking a PA and lateral simple radiography, as well as a follow-up evaluation accompanied with a CT angiography, DSA, and a color Doppler sonography. The examination involved the assessment of the difference between bone fractures due to length, placement, and frequency. Fractures occurred in 13 of 43 stents (30.2%). A total of 10 (71.4%) occurred in the upper third, compared to 4 (28.6%) in the lower third of the superficial femoral artery. In addition, 10 stents (71.4%) had a single strut fracture, whereas 4 (28.6%) had multiple strut fractures. A stent fracture occurred more frequently when the stents and lesions were longer (p=0.021, 0.012) and the stents were inserted near the joint. However, there was no significant relationship between stent numbers and the fractures (p=0.126). When the stents were inserted along the popliteal artery, a stent fracture occurred more frequently in the lower third of the artery. The stent fractures did not significantly influence the patency rate of the stented artery (p=0.44) Prote'ge'GPS stents in the superficial femoral artery revealed a considerable number of fractures and the fracture frequency showed a significant relationship with the length of stents and lesions. The closer stent insertion was to the joints, the more frequently fractures occurred. There were no evident significant relationships between the presence of stent fractures and the patency of the stented arteries

  12. Computer tomographic determination of femoral anteversion

    International Nuclear Information System (INIS)

    Jend, H.H.

    1986-01-01

    Thirty-two macerated femora were examined by CT in order to determine the degree of anteversion and to relate this to the position of the femur and to the various reference lines quoted in the literature. The accuracy of CT is the same as that of the Rippstein method, provided the following conditions are met: 1. Position of the femur with its long axis perpendicular to the image plane. 2. Demonstration of the maximal configuration of the femoral condyles to enable one to construct a tangent to the dorsal aspect of the condyle. 3. Demonstration of the head and neck by a plane which divides the neck into approximately equal portions and sections the femoral head. These conditions are more easily met, even in immobile patients, than the requirements for the Rippstein method. (orig.) [de

  13. Intracorporeal knotting of a femoral nerve catheter

    Directory of Open Access Journals (Sweden)

    Ghanem, Mohamed

    2015-01-01

    Full Text Available Peripheral nerve catheters are effective and well-established tools to provide postoperative analgesia to patients undergoing orthopedic surgery. The performance of these techniques is usually considered safe. However, placement of nerve catheters may be associated with a considerable number of side effects and major complications have repeatedly been published. In this work, we report on a patient who underwent total knee replacement with spinal anesthesia and preoperative insertion of femoral and sciatic nerve catheters for postoperative analgesia. During insertion of the femoral catheter, significant resistance was encountered upon retracting the catheter. This occurred due to knotting of the catheter. The catheter had to be removed by operative intervention which has to be considered a major complication. The postoperative course was uneventful. The principles for removal of entrapped peripheral catheters are not well established, may differ from those for neuroaxial catheters, and range from cautious manipulation up to surgical intervention.

  14. Femoral head fracture without hip dislocation

    Directory of Open Access Journals (Sweden)

    Aggarwal Aditya K

    2013-10-01

    Full Text Available 【Abstract】Femoral head fractures without dislocation or subluxation are extremely rare injuries. We report a neglected case of isolated comminuted fracture of femoral head without hip dislocation or subluxation of one year duration in a 36-year-old patient who sustained a high en- ergy trauma due to road traffic accident. He presented with painful right hip and inability to bear full weight on right lower limb with Harris hip score of 39. He received cementless total hip replacement. At latest follow-up of 2.3 years, functional outcome was excellent with Harris hip score of 95. Such isolated injuries have been described only once in the literature and have not been classified till now. The purpose of this report is to highlight the extreme rarity, possible mechanism involved and a novel classification system to classify such injuries. Key words: Femur head; Hip dislocation; Classification; Arthroplasty, replacement, hip

  15. Spontaneous stress fractures of the femoral neck

    International Nuclear Information System (INIS)

    Dorne, H.L.; Lander, P.H.

    1985-01-01

    The diagnosis of spontaneous stress fractures of the femoral neck, a form of insufficiency stress fracture, can be missed easily. Patients present with unremitting hip pain without a history of significant trauma or unusual increase in daily activity. The initial radiographic features include osteoporosis, minor alterations of trabecular alignment, minimal extracortical or endosteal reaction, and lucent fracture lines. Initial scintigraphic examinations performed in three of four patients showed focal increased radionuclide uptake in two and no focal abnormality in one. Emphasis is placed on the paucity of early findings. Evaluation of patients with persistent hip pain requires a high degree of clinical suspicion and close follow-up; the sequelae of undetected spontaneous fractures are subcapital fracture with displacement, angular deformity, and a vascular necrosis of the femoral head

  16. Is Botulinum Toxin Type A a Valuable Adjunct During Femoral Lengthening? A Randomized Trial.

    Science.gov (United States)

    Park, Hoon; Shin, Soowan; Shin, Han Sol; Kim, Hyun Woo; Kim, Dong Wook; Lee, Dong Hoon

    2016-12-01

    Reduced joint ROM and distraction-induced pain are common complaints of patients who have undergone gradual femoral lengthening. Attempts to reduce the effects of lengthening on joint motion have included the use of botulinum toxin to reduce the muscle forces that restrict motion. The benefits of this approach during femoral lengthening, however, have not been conclusively established. We wished to evaluate the effects of botulinum toxin type A (BtX-A) injection in the anterior thigh muscles during femoral distraction osteogenesis on adjacent joint ROM and distraction-induced pain. We asked: (1) Does injection of BtX-A in the quadriceps muscles lead to improved knee and hip motion during femoral lengthening? (2) Does injection of BtX-A reduce pain during femoral lengthening? A single-center, double-blind, randomized placebo-controlled trial was conducted. Forty-four patients (88 femurs) undergoing bilateral femoral lengthening for familial short stature were included in the study. BtX-A (200 IU) was injected intraoperatively in the quadriceps muscles of one thigh. An equal volume of sterile normal saline was injected in the other thigh as a control. Selection of the limb receiving the toxin was randomized. Clinical evaluation included a VAS score for pain measurement, ROM evaluation of the hips and knees, and measurement of thigh circumference. Side-to-side differences were analyzed throughout the entire consolidation phase. No patients were lost to followup, leaving 44 patients (88 femurs). The mean followup was 26 months (range, 14-40 months). The distraction rate and final length of gain were similar between treated and control limbs. A priori power analysis suggested that 44 legs were required in each group to achieve statistical significance of 0.05 with 90% power to detect a 50% difference in treatment effect between treatment and control groups. There were no differences in hip ROM, knee ROM, or maximal thigh circumference between the two lower extremities

  17. Ipsilateral femoral neck and trochanter fracture

    Directory of Open Access Journals (Sweden)

    Devdatta S Neogi

    2011-01-01

    Full Text Available Ipsilateral fractures in the neck and trochanteric region of the femur are very rare and seen in elderly osteoporotic patients. We present a case of a young man who presented with ipsilateral fracture of the femoral neck and a reverse oblique fracture in the trochanteric region following a motor vehicle accident. A possible mechanism, diagnostic challenge, and awareness required for identifying this injury are discussed.

  18. Proximal focal femoral deficiency: A case report

    Directory of Open Access Journals (Sweden)

    Shashank Sharma

    2015-01-01

    Full Text Available Proximal focal femoral deficiency (PFFD is a rare congenital anomaly resulting in limb shortening and disability in young. The exact cause of the disease is not known and it may present as varying grades of affection involving the proximal femur and the acetabulum. Recognition of this rare abnormality on radiographs can help manage these cases better since early institution of therapy may help in achieving adequate growth of the femur.

  19. Radiofrequency ablation of two femoral head chondroblastomas

    Energy Technology Data Exchange (ETDEWEB)

    Petsas, Theodore [Department of Radiology, University of Patras (Greece); Megas, Panagiotis [Department of Orthopaedic Surgery, University of Patras (Greece)]. E-mail: panmegas@med.upatras.gr; Papathanassiou, Zafiria [Department of Radiology, University of Patras (Greece)

    2007-07-15

    Chondroblastoma is a rare benign cartilaginous bone tumor. Surgical resection is the treatment of choice for pain relief and prevention of further growth. Open surgical techniques are associated with complications, particularly when the tumors are located in deep anatomical sites. The authors performed RF ablation in two cases of subarticular femoral head chondroblastomas and emphasize its positive impact. The clinical course, the radiological findings and the post treatment results are discussed.

  20. [Avascular necrosis of the femoral head].

    Science.gov (United States)

    Porubský, Peter; Trč, Tomáš; Havlas, Vojtěch; Smetana, Pavel

    Avascular necrosis of the femoral head in adults is not common, but not too rare diseases. In orthopedic practice, it is one of the diseases that are causing implantation of hip replacement at a relatively early age. In the early detection and initiation of therapy can delay the implantation of prosthesis for several years, which is certainly more convenient for the patient and beneficial. This article is intended to acquaint the reader with the basic diagnostic procedures and therapy.

  1. The Beginner's Guide to Wind Tunnels with TunnelSim and TunnelSys

    Science.gov (United States)

    Benson, Thomas J.; Galica, Carol A.; Vila, Anthony J.

    2010-01-01

    The Beginner's Guide to Wind Tunnels is a Web-based, on-line textbook that explains and demonstrates the history, physics, and mathematics involved with wind tunnels and wind tunnel testing. The Web site contains several interactive computer programs to demonstrate scientific principles. TunnelSim is an interactive, educational computer program that demonstrates basic wind tunnel design and operation. TunnelSim is a Java (Sun Microsystems Inc.) applet that solves the continuity and Bernoulli equations to determine the velocity and pressure throughout a tunnel design. TunnelSys is a group of Java applications that mimic wind tunnel testing techniques. Using TunnelSys, a team of students designs, tests, and post-processes the data for a virtual, low speed, and aircraft wing.

  2. 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...

  3. Tunnelling of a molecule

    International Nuclear Information System (INIS)

    Jarvis, P.D.; Bulte, D.P.

    1998-01-01

    A quantum-mechanical description of tunnelling is presented for a one-dimensional system with internal oscillator degrees of freedom. The 'charged diatomic molecule' is frustrated on encountering a barrier potential by its centre of charge not being coincident with its centre of mass, resulting in transitions amongst internal states. In an adiabatic limit, the tunnelling of semiclassical coherent-like oscillator states is shown to exhibit the Hartman and Bueuttiker-Landauer times t H and t BL , with the time dependence of the coherent state parameter for the tunnelled state given by α(t) = α e -iω(t+Δt) , Δt = t H - it BL . A perturbation formalism is developed, whereby the exact transfer matrix can be expanded to any desired accuracy in a suitable limit. An 'intrinsic' time, based on the oscillator transition rate during tunnelling, transmission or reflection, is introduced. In simple situations the resulting intrinsic tunnelling time is shown to vanish to lowest order. In the general case a particular (nonzero) parametrisation is inferred, and its properties discussed in comparison with the literature on tunnelling times for both wavepackets and internal clocks. Copyright (1998) CSIRO Australia

  4. MYCOTIC FEMORAL PSEUDOANEURYSMS FROM INTRAVENOUS DRUG ABUSE

    Directory of Open Access Journals (Sweden)

    Vojko Flis

    2004-04-01

    Full Text Available Background. Parenteral drug abuse is the most common cause of infected femoral artery pseudoaneurysms (IFAP. This complication of intravenous drug abuse is not only limb threatening but can also be life threatening. The management of the IFAP is difficult and controversial. Generally speaking, ligation and excision of the pseudoaneurysm without revascularization is accepted procedure in majority of the patients. However it is not regarded as an appropriate procedure for cases where the high probability of amputation is expected from acute interruption of the femoral artery flow.Patients, methods and results. We present three cases of young (average 20 years, range 18–24 patients with IFAP, in which a primary reconstruction was performed due to absence of doppler signal over pedal arteries after ligation of common femoral artery. In two of them complications in form of haemorrhage and repeated infection developed in late postoperative period. The first one, had an excision and ligation while the second one had a reconstruction made by means of a silver impregnated dacron prosthesis. None of the patients required an amputation.Conclusions. Overall prognosis and prognosis of the reconstruction in parenteral drug abuse patients is uncertain because there is a high incidence of postoperative drug injection despite aggressive drug rehabilitation.

  5. Radionuclide patterns of femoral head disease

    Energy Technology Data Exchange (ETDEWEB)

    Webber, M M; Wagner, J; Cragin, M D [California Univ., Los Angeles (USA). Dept. of Radiological Sciences

    1977-12-01

    The pattern of uptake of bone marrow specific radio-sup(99m)Tc sulfur colloid and the pattern of uptake of bone mineral specific radio-sup(99m)Tc pryophosphate may be valuable in assessing bone vascularity in diseases suspected of causing impaired blood supply, or indicate the presence of reactive bone formation. The low energy of the technetium label has been shown to be superior to /sup 18/F and /sup 85/Sr, and leads to greater imaging detail on the scans. Femoral head scanning with mineral and/or marrow specific radionuclides offers the clinician a method of evaluating the status of the femoral head and possibly an early diagnosis of avascular necrosis before roentgenographic changes occur. This study, which reports on a 5-year experience using radionuclide scanning to assess femoral head vascularity, begins with baseline or normal studies followed by variations of the normal pattern. Typical scan patterns of hip pathology described above are also presented.

  6. Temperature dependence of shot noise in double barrier magnetic tunnel junctions

    Science.gov (United States)

    Niu, Jiasen; Liu, Liang; Feng, J. F.; Han, X. F.; Coey, J. M. D.; Zhang, X.-G.; Wei, Jian

    2018-03-01

    Shot noise reveals spin dependent transport properties in a magnetic tunnel junction. We report measurement of shot noise in CoFeB/MgO/CoFeB/MgO/CoFeB double barrier magnetic tunnel junctions, which shows a strong temperature dependence. The Fano factor used to characterize shot noise increases with decreasing temperature. A sequential tunneling model can be used to account for these results, in which a larger Fano factor results from larger spin relaxation length at lower temperatures.

  7. 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

  8. Ipsilateral femoral neck and shaft fractures: An overlooked association

    International Nuclear Information System (INIS)

    Daffner, R.H.; Riemer, B.L.; Butterfield, S.L.

    1991-01-01

    A total of 304 patients with injuries to the femoral shaft and ipsilateral hip presented between 1984 and 1990. Some 253 of them suffered fractures of the femoral shaft and dislocated hips or fractures of the acetabulum, and 51 of these sustained fractures of the femoral shaft and neck or trochanteric region. All of the trochanteric injuries were demonstrated on the initial radiographs. However, in 11 of the patients with combined femoral shaft and neck fractures, the diagnosis was delayed by as much as 4 weeks. This delay related to the fact that these fractures tended not to separate in the initial evaluation period and that there was external rotation of the proximal femoral fragment due to the femoral shaft fracture. (orig./GDG)

  9. Ipsilateral femoral neck and shaft fractures: An overlooked association

    Energy Technology Data Exchange (ETDEWEB)

    Daffner, R.H. (Dept. of Diagnostic Radiology, Allegheny General Hospital, Pittsburgh, PA (USA) Medical Coll. of Pennsylvania, Pittsburgh, PA (USA)); Riemer, B.L.; Butterfield, S.L. (Dept. of Orthopedic Surgery, Allegheny General Hospital, Pittsburgh, PA (USA) Medical Coll. of Pennsylvania, Pittsburgh, PA (USA))

    1991-05-01

    A total of 304 patients with injuries to the femoral shaft and ipsilateral hip presented between 1984 and 1990. Some 253 of them suffered fractures of the femoral shaft and dislocated hips or fractures of the acetabulum, and 51 of these sustained fractures of the femoral shaft and neck or trochanteric region. All of the trochanteric injuries were demonstrated on the initial radiographs. However, in 11 of the patients with combined femoral shaft and neck fractures, the diagnosis was delayed by as much as 4 weeks. This delay related to the fact that these fractures tended not to separate in the initial evaluation period and that there was external rotation of the proximal femoral fragment due to the femoral shaft fracture. (orig./GDG).

  10. MR evaluation of femoral neck version and tibial torsion

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, James Karl; Dwek, Jerry R. [University of California, San Diego, Children' s Hospital and Health Center, Department of Radiology, San Diego, CA (United States); Pring, Maya E. [Rady Children' s Hospital, Department of Pediatric Orthopedic Surgery, San Diego, CA (United States)

    2012-01-15

    Abnormalities of femoral neck version have been associated with a number of hip abnormalities in children, including slipped capital femoral epiphysis, proximal femoral focal deficiency, coxa vara, a deep acetabulum and, rarely, developmental dysplasia of the hip. Orthopedic surgeons also are interested in quantifying the femoral neck anteversion or retroversion in children especially to plan derotational osteotomies. Historically, the angle of femoral version and tibial torsion has been measured with the use of radiography and later by CT. Both methods carry with them the risks associated with ionizing radiation. Techniques that utilize MR are used less often because of the associated lengthy imaging times. This article describes a technique using MRI to determine femoral neck version and tibial torsion with total scan times of approximately 10 min. (orig.)

  11. Computerized tomography in evaluation of decreased acetabular and femoral anteversion

    International Nuclear Information System (INIS)

    Toennis, D.; Skamel, H.J.

    2003-01-01

    Computerized tomography has received a new importance. It has been shown that decreased anteversion of femur and acetabulum, when both have decreased angles, are causing pain and osteoarthritis of the hip joint. Operative treatment should be performed before osteoarthritis develops. Exact measurements therefore are necessary. The investigation should be performed in prone position to have the pelvis lying in a defined and normal position. Femoral torsion is measured between the transverse axis of the knee and the femoral neck. The transverse axis for measurement of the femoral anteversion is defined by a rectangular line to the sagittal plane. For evaluation of the femoral anteversion in total the angle of the condyles has to be added to the femoral neck angle when the knee is found in internal rotation. Acetabular anteversion should be measured at the level where the femoral head is still in full contact and congruence with the anterior margin of the acetabulum. (orig.) [de

  12. Compartment Syndrome following Open Femoral Fracture with an Isolated Femoral Vein Injury Treated with Acute Repair

    Directory of Open Access Journals (Sweden)

    David Walmsley

    2014-01-01

    Full Text Available Acute compartment syndrome is a surgical emergency and its diagnosis is more difficult in obtunded or insensate patients. We present the case of a 34-year-old woman who sustained a Gustilo-Anderson grade III open midshaft femur fracture with an isolated femoral vein injury treated with direct repair. She developed lower leg compartment syndrome at 48 hours postoperatively, necessitating fasciotomies. She was subsequently found to have a DVT in her femoral vein at the level of the repair and was started on therapeutic anticoagulation. This case highlights the importance of recognition of isolated venous injuries in a trauma setting as a risk factor for developing compartment syndrome.

  13. Leg lengthening and femoral-offset reduction after total hip arthroplasty: where is the problem - stem or cup positioning?

    Science.gov (United States)

    Al-Amiry, Bariq; Mahmood, Sarwar; Krupic, Ferid; Sayed-Noor, Arkan

    2017-09-01

    Background Restoration of femoral offset (FO) and leg length is an important goal in total hip arthroplasty (THA) as it improves functional outcome. Purpose To analyze whether the problem of postoperative leg lengthening and FO reduction is related to the femoral stem or acetabular cup positioning or both. Material and Methods Between September 2010 and April 2013, 172 patients with unilateral primary osteoarthritis treated with THA were included. Postoperative leg-length discrepancy (LLD) and global FO (summation of cup and FO) were measured by two observers using a standardized protocol for evaluation of antero-posterior plain hip radiographs. Patients with postoperative leg lengthening ≥10 mm (n = 41) or with reduced global FO >5 mm (n = 58) were further studied by comparing the stem and cup length of the operated side with the contralateral side in the lengthening group, and by comparing the stem and cup offset of the operated side with the contralateral side in the FO reduction group. We evaluated also the inter-observer and intra-observer reliability of the radiological measurements. Results Both observers found that leg lengthening was related to the stem positioning while FO reduction was related to the positioning of both the femoral stem and acetabular cup. Both inter-observer reliability and intra-observer reproducibility were moderate to excellent (intra-class correlation co-efficient, ICC ≥0.69). Conclusion Post THA leg lengthening was mainly caused by improper femoral stem positioning while global FO reduction resulted from improper positioning of both the femoral stem and the acetabular cup.

  14. Crossover from quantum tunneling to classical hopping of domain walls in ferromagnets

    Science.gov (United States)

    Zhou, Bin; Liang, Jiu-Qing; Pu, Fu-Cho

    2001-09-01

    In the model of quantum tunneling of domain walls in ferromagnets given by Chudnovsky et al., the crossover from quantum tunneling to classical hopping is investigated. Considering the periodical boundary condition of spatial coordinate, the type of transition depends critically on the length of ferromagnet along the Y-axis.

  15. Delayed appearance of hypaesthesia and paralysis after femoral nerve block

    OpenAIRE

    Stefan Landgraeber; Thomas Albrecht; Ulrich Reischuck; Marius von Knoch

    2012-01-01

    We report on a female patient who underwent an arthroscopy of the right knee and was given a continuous femoral nerve block catheter. The postoperative course was initially unremarkable, but when postoperative mobilisation was commenced, 18 hours after removal of the catheter, the patient noticed paralysis and hypaesthesia. Examination confirmed the diagnosis of femoral nerve dysfunction. Colour duplex sonography of the femoral artery and computed tomography of the lumbar spine and pelvis yie...

  16. Single Electron Tunneling

    International Nuclear Information System (INIS)

    Ruggiero, Steven T.

    2005-01-01

    Financial support for this project has led to advances in the science of single-electron phenomena. Our group reported the first observation of the so-called ''Coulomb Staircase'', which was produced by tunneling into ultra-small metal particles. This work showed well-defined tunneling voltage steps of width e/C and height e/RC, demonstrating tunneling quantized on the single-electron level. This work was published in a now well-cited Physical Review Letter. Single-electron physics is now a major sub-field of condensed-matter physics, and fundamental work in the area continues to be conducted by tunneling in ultra-small metal particles. In addition, there are now single-electron transistors that add a controlling gate to modulate the charge on ultra-small photolithographically defined capacitive elements. Single-electron transistors are now at the heart of at least one experimental quantum-computer element, and single-electron transistor pumps may soon be used to define fundamental quantities such as the farad (capacitance) and the ampere (current). Novel computer technology based on single-electron quantum dots is also being developed. In related work, our group played the leading role in the explanation of experimental results observed during the initial phases of tunneling experiments with the high-temperature superconductors. When so-called ''multiple-gap'' tunneling was reported, the phenomenon was correctly identified by our group as single-electron tunneling in small grains in the material. The main focus throughout this project has been to explore single electron phenomena both in traditional tunneling formats of the type metal/insulator/particles/insulator/metal and using scanning tunneling microscopy to probe few-particle systems. This has been done under varying conditions of temperature, applied magnetic field, and with different materials systems. These have included metals, semi-metals, and superconductors. Amongst a number of results, we have

  17. Aespoe Hard Rock Laboratory. The TASS-tunnel. Geological mapping

    Energy Technology Data Exchange (ETDEWEB)

    Hardenby, Carljohan (Vattenfall Power Consultant AB (Sweden)); Sigurdsson, Oskar (HAskGeokonsult AB (Sweden))

    2010-12-15

    The project entitled 'Sealing of tunnel at great depth' (Fintaetning av tunnel paa stort djup) needed a new tunnel in an area as undisturbed as possible and with cross-cutting water-bearing structures. The new tunnel, which was given the name TASS, was excavated on the -450 m level of SKB's Aespoe Hard Rock Laboratory (Aespoe HRL). The length of the tunnel is approximately 80 m and the theoretical tunnel area 19 m2. As is the case with all the other tunnels of the Aespoe HRL, the new tunnel has been geologically mapped. In addition, laser scanning combined with digital photography has been carried out. The tunnel was also used to test various types of explosives, borehole layouts and drilling techniques. The geological mapping of tunnel floor, walls and roof took place on four major occasions when a halt was made in tunnel excavation to allow for various tests. Before the mapping started on these occasions, laser scanning took place. The tunnel faces were mapped after each round (drilling, blasting and unloading). The present report describes the geological features of the tunnel and briefly how the laser scanning was performed. Water-bearing structures have been compared to similar structures in the neighbouring tunnels. The rock type names used here follow the old established Aespoe HRL nomenclature. Narrow (<0.1 m wide) dykes are normally mapped as fracture fillings. The dominating rock type is Aespoe diorite, which constitutes some 90 % of the rock mass. It is mostly mapped as fresh rock. . Minor constituents of the rock mass are fine-grained granite, hybrid rock, pegmatite, quartz veins/lenses and undifferentiated mafic rock. The mapping of fractures and deformation zones considers a number of parameters such as number of fractures, open/healed, width, length, description of fracture surfaces (roughness, planarity, etc), fracture filling, alteration and water. The deformation zones are discriminated into two main categories (&apos

  18. Aespoe Hard Rock Laboratory. The TASS-tunnel. Geological mapping

    International Nuclear Information System (INIS)

    Hardenby, Carljohan; Sigurdsson, Oskar

    2010-12-01

    The project entitled 'Sealing of tunnel at great depth' (Fintaetning av tunnel paa stort djup) needed a new tunnel in an area as undisturbed as possible and with cross-cutting water-bearing structures. The new tunnel, which was given the name TASS, was excavated on the -450 m level of SKB's Aespoe Hard Rock Laboratory (Aespoe HRL). The length of the tunnel is approximately 80 m and the theoretical tunnel area 19 m 2 . As is the case with all the other tunnels of the Aespoe HRL, the new tunnel has been geologically mapped. In addition, laser scanning combined with digital photography has been carried out. The tunnel was also used to test various types of explosives, borehole layouts and drilling techniques. The geological mapping of tunnel floor, walls and roof took place on four major occasions when a halt was made in tunnel excavation to allow for various tests. Before the mapping started on these occasions, laser scanning took place. The tunnel faces were mapped after each round (drilling, blasting and unloading). The present report describes the geological features of the tunnel and briefly how the laser scanning was performed. Water-bearing structures have been compared to similar structures in the neighbouring tunnels. The rock type names used here follow the old established Aespoe HRL nomenclature. Narrow (<0.1 m wide) dykes are normally mapped as fracture fillings. The dominating rock type is Aespoe diorite, which constitutes some 90 % of the rock mass. It is mostly mapped as fresh rock. . Minor constituents of the rock mass are fine-grained granite, hybrid rock, pegmatite, quartz veins/lenses and undifferentiated mafic rock. The mapping of fractures and deformation zones considers a number of parameters such as number of fractures, open/healed, width, length, description of fracture surfaces (roughness, planarity, etc), fracture filling, alteration and water. The deformation zones are discriminated into two main categories ('increased fracturing' and

  19. Resonant tunnel magnetoresistance in a double magnetic tunnel junction

    KAUST Repository

    Useinov, Arthur; Useinov, Niazbeck Kh H; Tagirov, Lenar R.; Kosel, Jü rgen

    2011-01-01

    We present quasi-classical approach to calculate a spin-dependent current and tunnel magnetoresistance (TMR) in double magnetic tunnel junctions (DMTJ) FML/I/FMW/I/FMR, where the magnetization of the middle ferromagnetic metal layer FMW can

  20. Wind tunnel test of musi VI bridge

    Science.gov (United States)

    Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

    2017-11-01

    Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

  1. Interaction between groundwater and TBM (Tunnel Boring Machine) excavated tunnels

    OpenAIRE

    Font Capó, Jordi

    2012-01-01

    A number of problems, e.g. sudden inflows are encountered during tunneling under the piezometric level, especially when the excavation crosses high transmissivity areas. These inflows may drag materials when the tunnel crosses low competent layers, resulting in subsidence, chimney formation and collapses. Moreover, inflows can lead to a decrease in head level because of aquifer drainage. Tunnels can be drilled by a tunnel boring machine (TBM) to minimize inflows and groundwater impacts, restr...

  2. Quantum tunneling resonant electron transfer process in Lorentzian plasmas

    International Nuclear Information System (INIS)

    Hong, Woo-Pyo; Jung, Young-Dae

    2014-01-01

    The quantum tunneling resonant electron transfer process between a positive ion and a neutral atom collision is investigated in nonthermal generalized Lorentzian plasmas. The result shows that the nonthermal effect enhances the resonant electron transfer cross section in Lorentzian plasmas. It is found that the nonthermal effect on the classical resonant electron transfer cross section is more significant than that on the quantum tunneling resonant charge transfer cross section. It is shown that the nonthermal effect on the resonant electron transfer cross section decreases with an increase of the Debye length. In addition, the nonthermal effect on the quantum tunneling resonant electron transfer cross section decreases with increasing collision energy. The variation of nonthermal and plasma shielding effects on the quantum tunneling resonant electron transfer process is also discussed

  3. Challenges and Thoughts on Risk Management and Control for the Group Construction of a Super-Long Tunnel by TBM

    Directory of Open Access Journals (Sweden)

    Mingjiang Deng

    2018-02-01

    Full Text Available The total length of the second stage of the water supply project in the northern areas of the Xinjiang Uygur Autonomous Region is 540 km, of which the total length of the tunnels is 516 km. The total tunneling mileage is 569 km, which includes 49 slow-inclined shafts and vertical shafts. Among the tunnels constructed in the project, the Ka–Shuang tunnel, which is a single tunnel with a length of 283 km, is currently the longest water-conveyance tunnel in the world. The main tunnel of the Ka–Shuang tunnel is divided into 18 tunnel-boring machine (TBM sections, and 34 drilling-and-blasting sections, with 91 tunnel faces. The construction of the Ka–Shuang tunnel has been regarded as an unprecedented challenge for project construction management, risk control, and safe and efficient construction; it has also presented higher requirements for the design, manufacture, operation, and maintenance of the TBMs and their supporting equipment. Based on the engineering characteristics and adverse geological conditions, it is necessary to analyze the major problems confronted by the construction and systematically locate disaster sources. In addition, the risk level should be reasonably ranked, responsibility should be clearly identified, and a hierarchical-control mechanism should be established. Several techniques are put forward in this paper to achieve the objectives mentioned above; these include advanced geological prospecting techniques, intelligent tunneling techniques combined with the sensing and fusion of information about rock parameters and mechanical parameters, monitoring and early-warning techniques, and modern information technologies. The application of these techniques offers scientific guidance for risk control and puts forward technical ideas about improving the efficiency of safe tunneling. These techniques and ideas have great significance for the development of modern tunneling technologies and research into major

  4. Seepage into PEP tunnel

    International Nuclear Information System (INIS)

    Weidner, H.

    1990-01-01

    The current rate of seepage into the PEP tunnel in the vicinity of IR-10 is very low compared to previous years. Adequate means of handling this low flow are in place. It is not clear whether the reduction in the flow is temporary, perhaps due to three consecutive dry years, or permanent due to drainage of a perched water table. During PEP construction a large amount of effort was expended in attempts to seal the tunnel, with no immediate effect. The efforts to ''manage'' the water flow are deemed to be successful. By covering equipment to protect it from dripping water and channeling seepage into the drainage gutters, the seepage has been reduced to a tolerable nuisance. There is no sure, safe procedure for sealing a leaky shotcreted tunnel

  5. Uncooled tunneling infrared sensor

    Science.gov (United States)

    Kenny, Thomas W. (Inventor); Kaiser, William J. (Inventor); Podosek, Judith A. (Inventor); Vote, Erika C. (Inventor); Muller, Richard E. (Inventor); Maker, Paul D. (Inventor)

    1995-01-01

    An uncooled infrared tunneling sensor in which the only moving part is a diaphragm which is deflected into contact with a micromachined silicon tip electrode prepared by a novel lithographic process. Similarly prepared deflection electrodes employ electrostatic force to control the deflection of a silicon nitride, flat diaphragm membrane. The diaphragm exhibits a high resonant frequency which reduces the sensor's sensitivity to vibration. A high bandwidth feedback circuit controls the tunneling current by adjusting the deflection voltage to maintain a constant deflection of the membrane. The resulting infrared sensor can be miniaturized to pixel dimensions smaller than 100 .mu.m. An alternative embodiment is implemented using a corrugated membrane to permit large deflection without complicated clamping and high deflection voltages. The alternative embodiment also employs a pinhole aperture in a membrane to accommodate environmental temperature variation and a sealed chamber to eliminate environmental contamination of the tunneling electrodes and undesireable accoustic coupling to the sensor.

  6. To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Abhishek, E-mail: abhiortho27@gmail.co [Department of Orthopedics, 513, Thermal Colony, Sector-22, Faridabad 121005, Haryana (India); Sankaran, Balu; Varghese, Mathew [Department of Orthopedics, St Stephen' s Hospital, Tis hazari, Delhi, New Delhi 110054 (India)

    2010-09-15

    Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity after femoral neck fracture are 87%, 88% and 87%, respectively. Type A or Type B curve pattern is a positive factor to successful osteosynthesis with p value <0.0001 (Chi-square test). This is a statistically significant value. From this finding it can be suggested that the reliability of dynamic curves A and B in predicting maintained vascularity of femoral head is high. This investigation can be used to predict the vascularity of femoral head after intracapsular femoral neck fractures. There was a good correlation between the outcomes of fractures and dynamic MRI curves done within 48 h of injury. This signifies the role of dynamic MRI in predicting the vascularity of femoral head as early as 48 h. A treatment algorithm can be suggested on the basis of dynamic MRI curves. The fractures with Type C dynamic curve should be considered as fractures with poor vascularity of femoral head and measures to enhance the vascularity of femoral head along with rigid internal fixation should be undertaken to promote

  7. To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures

    International Nuclear Information System (INIS)

    Kaushik, Abhishek; Sankaran, Balu; Varghese, Mathew

    2010-01-01

    Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity after femoral neck fracture are 87%, 88% and 87%, respectively. Type A or Type B curve pattern is a positive factor to successful osteosynthesis with p value <0.0001 (Chi-square test). This is a statistically significant value. From this finding it can be suggested that the reliability of dynamic curves A and B in predicting maintained vascularity of femoral head is high. This investigation can be used to predict the vascularity of femoral head after intracapsular femoral neck fractures. There was a good correlation between the outcomes of fractures and dynamic MRI curves done within 48 h of injury. This signifies the role of dynamic MRI in predicting the vascularity of femoral head as early as 48 h. A treatment algorithm can be suggested on the basis of dynamic MRI curves. The fractures with Type C dynamic curve should be considered as fractures with poor vascularity of femoral head and measures to enhance the vascularity of femoral head along with rigid internal fixation should be undertaken to promote

  8. Surgery for pathological proximal femoral fractures, excluding femoral head and neck fractures: resection vs. stabilisation.

    Science.gov (United States)

    Zacherl, Max; Gruber, Gerald; Glehr, Mathias; Ofner-Kopeinig, Petra; Radl, Roman; Greitbauer, Manfred; Vecsei, Vilmos; Windhager, Reinhard

    2011-10-01

    Pathological femoral head and neck fractures are commonly treated by arthroplasty. Treatment options for the trochanteric region or below are not clearly defined. The purpose of this retrospective, comparative, double-centre study was to analyse survival and influences on outcome according to the surgical technique used to treat pathological proximal femoral fractures, excluding fractures of the femoral head and neck. Fifty-nine patients with 64 fractures were operated up on between 1998 and 2004 in two tertiary referral centres and divided into two groups. One group (S, n = 33) consisted of patients who underwent intramedullary nailing alone, and the other group (R, n = 31) consisted of patients treated by metastatic tissue resection and reconstruction by means of different implants. Median survival was 12.6 months with no difference between groups. Surgical complications were higher in the R group (n = 7) vs. the S group (n = 3), with no statistically significant difference. Patients with surgery-related complications had a higher survival rate (p = 0.049), as did patients with mechanical implant failure (p = 0.01). Survival scoring systems did not correlate with actual survival. Resection of metastases in patients with pathological fractures of the proximal femur, excluding femoral head and neck fractures, has no influence on survival. Patients with long postoperative survival prognosis are at risk of implant-related complications.

  9. Self-designed femoral neck guide pin locator for femoral neck fractures.

    Science.gov (United States)

    Xia, Shengli; Wang, Ziping; Wang, Minghui; Wu, Zuming; Wang, Xiuhui

    2014-01-01

    Closed reduction and fixation with 3 cannulated screws is a widely accepted surgery for the treatment of femoral neck fractures. However, how to obtain optimal screw placement remains unclear. In the current study, the authors designed a guide pin positioning system for femoral neck fracture cannulated screw fixation and examined its application value by comparing it with freehand guide needle positioning and with general guide pin locator positioning provided by equipment manufacturers. The screw reset rate, screw parallelism, triangle area formed by the link line of the entry point of 3 guide pins, and maximum vertical load bearing of the femoral neck after internal fixation were recorded. As expected, the triangle area was largest in the self-designed positioning group, followed by the general positioning group and the freehand positioning group. The difference among the 3 groups was statistically significant (P.05). The authors’ self-designed guide pin positioning system has the potential to accurately insert cannulated screws in femoral neck fractures and may reduce bone loss and unnecessary radiation.

  10. Evaluation of the Influence Caused by Tunnel Construction on Groundwater Environment: A Case Study of Tongluoshan Tunnel, China

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2015-01-01

    Full Text Available Problems related to water inflow during tunnel construction are challenging to designers, workers, and management departments, as they can threaten tunneling project from safety, time, and economic aspects. Identifying the impacts on groundwater environment resulting from tunnel drainage and making a correct assessment before tunnel construction is essential to better understand troubles that would be encountered during tunnel excavation and helpful to adopt appropriate countermeasures to minimize the influences. This study presents an indicator system and quantifies each indicator of Tongluoshan tunnel, which is located in southwest China with a length of 5.2 km and mainly passes through carbonate rocks and sandstones, based on field investigation and related technological reports. Then, an evaluation is made using fuzzy comprehensive assessment method, with a result showing that it had influenced the local groundwater environment at a moderate degree. Information fed back from environmental investigation and hydrologic monitoring carried out during the main construction period proves the evaluation, as the flow of some springs and streams located beside the tunnel route was found experiencing an apparent decline.

  11. Instabilities in thin tunnel junctions

    International Nuclear Information System (INIS)

    Konkin, M.K.; Adler, J.G.

    1978-01-01

    Tunnel junctions prepared for inelastic electron tunneling spectroscopy are often plagued by instabilities in the 0-500-meV range. This paper relates the bias at which the instability occurs to the barrier thickness

  12. Switching between dynamic states in intermediate-length Josephson junctions

    DEFF Research Database (Denmark)

    Pagano, S.; Sørensen, Mads Peter; Parmentier, R. D.

    1986-01-01

    The appearance of zero-field steps (ZFS’s) in the current-voltage characteristics of intermediate-length overlap-geometry Josephson tunnel junctions described by a perturbed sine-Gordon equation (PSGE) is associated with the growth of parametrically excited instabilities of the McCumber backgroun...

  13. Press-fit Femoral Fixation in ACL Reconstruction using Bone-Patellar Tendon-Bone Graft

    Directory of Open Access Journals (Sweden)

    Kaseb Mohammad Hasan

    2009-05-01

    Full Text Available Bone-patellar tendon auto graft is probably the most widely used graft for ACL reconstruction. Several methods for graft fixation have been described. To avoid intra-articular hardware we adopt biological fixation with a femoral trapezoidal press-fit fixation. A prospective study was performed on 30 consecutive active people who underwent ACL reconstruction with this technique by two surgeons between september2004 and march2007 (mean follow-up 15.2 months. Results were evaluated by an independent examiner using radiography, subjective and objective evaluation. Assessment using the IKDC knee scoring revealed 92% of the patients with a normal or nearly normal knee joint. Lysholm's score was 63.6(40- 86 preoperatively and 91.88(73-100 at the latest follow up (P < 0.005. No patient complained of instability at latest follow up. The quadriceps muscle showed mild atrophy at 3 and 6 months and at final follow-up. Five Patients complained of anterior knee pain and had a positive kneeling test. We found no graft displacement on follow up radiographs. All cases showed radiological evidence of graft osteointegration at last follow up. Our results show that press-fit fixation of trapezoidal bone graft in femoral tunnel is a simple, reliable, and cost-effective alternative for ACL recon-struction using bone-patellar tendon-bone graft.

  14. Biogeometry of femoral neck for implant placement

    Directory of Open Access Journals (Sweden)

    Patwa J

    2006-01-01

    Full Text Available Background : Treatment of fracture neck femur with three cannulated cancellous screws in an apex proximal configuration is practised in many parts of the world. Methods : Dimensions of femoral neck at the middle of transcervical neck using CT scan (live neck and vernier caliper (dry cadeveric neck in 20 subjects respectively were measured. Results : Inferior half of the neck is narrower than superior half. Conclusion : Biogeometry of the neck of femur does not accomodate two inferior screws and thus fixation of fracture neck femur with three canulated cancellous screws in an apex distal configuration is recommended.

  15. Superficial femoral artery: current treatment options

    International Nuclear Information System (INIS)

    Tepe, Gunnar; Schmehl, Joerg; Heller, Stephan; Wiesinger, Benjamin; Claussen, Claus D.; Duda, Stephan H.

    2006-01-01

    Treatment of the superficial femoral artery (SFA) has been among the least effective of all endovascular procedures in terms of long-term patency. The relatively small vessel lumen, in conjunction with a high plaque burden, slow flow, and a high frequency of primary occlusions, contributes to a considerable rate of acute technical failures. Because of these technical limitations a much effort has been made during the past years. This manuscript should summarize the hopes and limitations of different approaches such as brachytherapy, cutting balloons, stents and stent grafts, drug-eluting stents, and drug-coated balloons. (orig.)

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

    Science.gov (United States)

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

    2011-05-01

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

  17. Tunneling in axion monodromy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Jon; Cottrell, William; Shiu, Gary; Soler, Pablo [Department of Physics, University of Wisconsin,Madison, WI 53706 (United States)

    2016-10-06

    The Coleman formula for vacuum decay and bubble nucleation has been used to estimate the tunneling rate in models of axion monodromy in recent literature. However, several of Coleman’s original assumptions do not hold for such models. Here we derive a new estimate with this in mind using a similar Euclidean procedure. We find that there are significant regions of parameter space for which the tunneling rate in axion monodromy is not well approximated by the Coleman formula. However, there is also a regime relevant to large field inflation in which both estimates parametrically agree. We also briefly comment on the applications of our results to the relaxion scenario.

  18. LEP tunnel monorail

    CERN Multimedia

    1985-01-01

    A monorail from CERN's Large Electron Positron collider (LEP, for short). It ran around the 27km tunnel, transporting equipment and personnel. With its 27-kilometre circumference, LEP was the largest electron-positron accelerator ever built and ran from 1989 to 2000. During 11 years of research, LEP's experiments provided a detailed study of the electroweak interaction. Measurements performed at LEP also proved that there are three – and only three – generations of particles of matter. LEP was closed down on 2 November 2000 to make way for the construction of the Large Hadron Collider in the same tunnel.

  19. Excavating a transfer tunnel

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    The transfer tunnel being dug here will take the 450 GeV beam from the SPS and inject it into the LHC where the beam energies will be increased to 7 TeV. In order to transfer this beam from the SPS to the LHC, two transfer tunnels are used to circulate the beams in opposite directions. When excavated, the accelerator components, including magnets, beam pipes and cryogenics will be installed and connected to both the SPS and LHC ready for operation to begin in 2008.

  20. Gap anisotropy and tunneling currents. [MPS3

    DEFF Research Database (Denmark)

    Lazarides, N.; Sørensen, Mads Peter

    1996-01-01

    The tunneling Hamiltonian formalism is applied to calculate the tunnelingcurrents through a small superconducting tunnel junction. The formalism isextended to nonconstant tunneling matrix elements. The electrodes of thejunction are assumed to......The tunneling Hamiltonian formalism is applied to calculate the tunnelingcurrents through a small superconducting tunnel junction. The formalism isextended to nonconstant tunneling matrix elements. The electrodes of thejunction are assumed to...

  1. Breaking through the tranfer tunnel

    CERN Document Server

    Laurent Guiraud

    2001-01-01

    This image shows the tunnel boring machine breaking through the transfer tunnel into the LHC tunnel. Proton beams will be transferred from the SPS pre-accelerator to the LHC at 450 GeV through two specially constructed transfer tunnels. From left to right: LHC Project Director, Lyn Evans; CERN Director-General (at the time), Luciano Maiani, and Director for Accelerators, Kurt Hubner.

  2. Control of tunneling in heterostructures

    International Nuclear Information System (INIS)

    Volokhov, V M; Tovstun, C A; Ivlev, B

    2007-01-01

    A tunneling current between two rectangular potential wells can be effectively controlled by applying an external ac field. A variation of the ac frequency by 10% may lead to the suppression of the tunneling current by two orders of magnitude, which is a result of quantum interference under the action of the ac field. This effect of destruction of tunneling can be used as a sensitive control of tunneling current across nanosize heterostructures

  3. Concurrent myotomy and tunneling after establishment of a half tunnel instead of myotomy after establishment of a full tunnel: a more efficient method of peroral endoscopic myotomy.

    Science.gov (United States)

    Philips, George M; Dacha, Sunil; Keilin, Steve A; Willingham, Field F; Cai, Qiang

    2016-04-01

    Peroral endoscopic myotomy (POEM) is a time-consuming and challenging procedure. Traditionally, the myotomy is done after the submucosal tunnel has been completed. Starting the myotomy earlier, after submucosal tunneling is half completed (concurrent myotomy and tunneling), may be more efficient. This study aims to assess if the method of concurrent myotomy and tunneling may decrease the procedural time and be efficacious. This is a retrospective case series of patients who underwent modified POEM (concurrent myotomy and tunneling) or traditional POEM at a tertiary care medical center. Modified POEM or traditional POEM was performed at the discretion of the endoscopist in patients presenting with achalasia. The total procedural duration, myotomy duration, myotomy length, and time per unit length of myotomy were recorded for both modified and traditional POEM. Modified POEM was performed in 6 patients whose mean age (± standard deviation [SD]) was 58 ± 13.3 years. Of these, 5 patients had type II achalasia and 1 patient had esophageal dysmotility. The mean Eckardt score (± SD) before the procedure was 8.8 ± 1.3. The modified technique was performed in 47 ± 8 minutes, with 6 ± 1 minutes required per centimeter of myotomy and 3 ± 1 minutes required per centimeter of submucosal space. The Eckardt score was 3 ± 1.1 at 1 month and 3 ± 2.5 at 3 months. The procedure time for modified POEM was significantly shorter than that for traditional POEM. Modified POEM with short submucosal tunneling may be more efficient than traditional POEM with long submucosal tunneling, and outcomes may be equivalent over short-term follow-up. Long-term data and randomized controlled studies are needed to compare the clinical efficacy of modified POEM with that of the traditional method.

  4. Location of civilian ballistic femoral fracture indicates likelihood of arterial injury.

    Science.gov (United States)

    Gitajn, Leah; Perdue, Paul; Hardcastle, John; O'Toole, Robert V

    2014-10-01

    We evaluated whether the location of a ballistic femoral fracture helps predict the presence of arterial injury. We hypothesized that fractures located in the distal third of the femur are associated with a higher rate of arterial injury. We conducted a retrospective review of electronic medical records at our level I trauma centre and found 133 consecutive patients with femoral fractures from civilian gunshots from 2002 to 2007, 14 of whom sustained arterial injury. Fracture extent was measured with computerized viewing software and recorded with a standard technique, calculating proximal, distal, and central locations of the fracture as a function of overall length of the bone. Analyses were conducted with Student's t, Chi-squared, and Fisher's exact tests. The location of any fracture line in the distal third of the femur was associated with increased risk of arterial injury (Pballistic injury is six times more likely to be associated with arterial injury and warrants careful evaluation. Our data show that fracture location can help alert clinicians to possible arterial injury after ballistic femoral fracture. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi [University of California Irvine, Department of Radiological Sciences, Orange, CA (United States); Kaneshiro, Kayleigh [University of California Irvine, School of Medicine, Irvine, CA (United States); Schwarzkopf, Ran [University of California Irvine, Department of Orthopedic Surgery, Irvine, CA (United States); Hara, Takeshi [Gifu University Graduate School of Medicine, Department of Intelligent Image Information, Division of Regeneration and Advanced Medical Sciences, Gifu (Japan)

    2016-06-15

    To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

  6. Ultrasound-guided block of sciatic and femoral nerves: an anatomical study.

    Science.gov (United States)

    Waag, Sonja; Stoffel, Michael H; Spadavecchia, Claudia; Eichenberger, Urs; Rohrbach, Helene

    2014-04-01

    The sheep is a popular animal model for human biomechanical research involving invasive surgery on the hind limb. These painful procedures can only be ethically justified with the application of adequate analgesia protocols. Regional anaesthesia as an adjunct to general anaesthesia may markedly improve well-being of these experimental animals during the postoperative period due to a higher analgesic efficacy when compared with systemic drugs, and may therefore reduce stress and consequently the severity of such studies. As a first step 14 sheep cadavers were used to establish a new technique for the peripheral blockade of the sciatic and the femoral nerves under sonographic guidance and to evaluate the success rate by determination of the colorization of both nerves after an injection of 0.5 mL of a 0.1% methylene blue solution. First, both nerves were visualized sonographically. Then, methylene blue solution was injected and subsequently the length of colorization was measured by gross anatomical dissection of the target nerves. Twenty-four sciatic nerves were identified sonographically in 12 out of 13 cadavers. In one animal, the nerve could not be ascertained unequivocally and, consequently, nerve colorization failed. Twenty femoral nerves were located by ultrasound in 10 out of 13 cadavers. In three cadavers, signs of autolysis impeded the scan. This study provides a detailed anatomical description of the localization of the sciatic and the femoral nerves and presents an effective and safe yet simple and rapid technique for performing peripheral nerve blocks with a high success rate.

  7. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    International Nuclear Information System (INIS)

    Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi; Kaneshiro, Kayleigh; Schwarzkopf, Ran; Hara, Takeshi

    2016-01-01

    To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

  8. A-Frame free Vascularized Fibular Graft and Femoral Lengthening for Osteosarcoma Pediatric Patients.

    Science.gov (United States)

    Cashin, Megan; Coombs, Christopher; Torode, Ian

    2018-02-01

    Pediatric limb reconstruction after resection of a malignant tumor presents specific challenges. Multiple surgical techniques have been used to treat these patients. This paper describes a staged surgical technique for the reconstruction of large distal femoral defects due to tumor resection in skeletally immature patients. Three pediatric patients with osteosarcoma of the distal femur underwent staged reconstruction. Neoadjuvant chemotherapy was followed by en bloc tumor resection and immediate reconstruction of the distal femoral defect with a vascularized free fibular autograft utilizing a unique A-frame construct combined with intramedullary nail fixation. The second stage was a planned gradual lengthening of the healed construct, over a custom-made magnetically driven expandable intramedullary nail. All patients achieved bony union and satisfactory length with minimal complications. The patients all returned to full, unlimited physical activities. The early results confirm that the described technique is a safe and reliable procedure for the reconstruction of large femoral defects in pediatric patients with osteosarcoma. Level IV-therapeutic.

  9. Experimental investigations of the steady flow through an idealized model of a femoral artery bypass

    Directory of Open Access Journals (Sweden)

    Giurgea Corina

    2014-03-01

    Full Text Available The present paper presents the steps taken by the authors in the first stage of an experimental program within a larger national research project whose objective is to characterize the flow through a femoral artery bypass with a view to finding solutions for its optimization. The objective of the stage is to investigate by means of the PIV method the stationary flow through a bypass model with an idealized geometry. A bypass assembly which reunites the idealized geometry models of the proximal and distal anastomoses, and which respects the lengths of a femoral artery bypass was constructed on the basis of data for a real patient provided by medical investigations. With the aim of testing the model and the established experimental set-up with regard to their suitability for the assessment of the velocity field associated to the steady flow through the bypass, three zones that can restore the whole distal anastomosis were PIV investigated. The measurements were taken in the conditions of maintained inflow at the bypass entry of 0.9 l / min (Re = 600. The article presents comparatively the flow spectra and the velocity fields for each zone obtained in two situations: with the femoral artery completely occluded and completely open.

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

    Directory of Open Access Journals (Sweden)

    Chen Hsih-Hao

    2009-09-01

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

  11. Ivar Giaever, Tunneling, and Superconductors

    Science.gov (United States)

    dropdown arrow Site Map A-Z Index Menu Synopsis Ivar Giaever, Tunneling, and Superconductors Resources with in Superconductors Measured by Electron Tunneling; Physical Review Letters, Vol. 5 Issue 4: 147 - 148 ; August 15, 1960 Electron Tunneling Between Two Superconductors; Physical Review Letters, Vol. 5 Issue 10

  12. Scanning tunneling microscope nanoetching method

    Science.gov (United States)

    Li, Yun-Zhong; Reifenberger, Ronald G.; Andres, Ronald P.

    1990-01-01

    A method is described for forming uniform nanometer sized depressions on the surface of a conducting substrate. A tunneling tip is used to apply tunneling current density sufficient to vaporize a localized area of the substrate surface. The resulting depressions or craters in the substrate surface can be formed in information encoding patterns readable with a scanning tunneling microscope.

  13. Physics of optimal resonant tunneling

    NARCIS (Netherlands)

    Racec, P.N.; Stoica, T.; Popescu, C.; Lepsa, M.I.; Roer, van de T.G.

    1997-01-01

    The optimal resonant tunneling, or the complete tunneling transparence of a biased double-barrier resonant-tunneling (DBRT) structure, is discussed. It is shown that its physics does not rest on the departure from the constant potential within the barriers and well, due to the applied electric

  14. [Postoperative analgesia in knee arthroplasty using an anterior sciatic nerve block and a femoral nerve block].

    Science.gov (United States)

    del Fresno Cañiaveras, J; Campos, A; Galiana, M; Navarro-Martínez, J A; Company, R

    2008-11-01

    To evaluate the efficacy of a nerve block as an alternative technique for analgesia after knee arthroplasty and to indicate the usefulness and advantages of the anterior approach to the sciatic nerve block. Between April 2004 and March 2006, we studied a series of consecutive patients undergoing knee arthroplasty in which a subarachnoid block was used as the anesthetic technique and postoperative analgesia was provided by means of a combined peripheral femoral nerve block and an anterior sciatic nerve block. We evaluated the mean length of time free from pain, quality of analgesia, and length of stay in hospital. Seventy-eight patients were included in the study. The mean (SD) length of time free from pain for the group was 42.1 (3.9) hours. Patients reported mild pain after 34.8 (4.1) hours and moderate to severe pain after 42.4 (3.5) hours. By the third day, 62.8% of patients were able to bend the knee to 90 degrees. There were no complications resulting from the technique and the level of patient satisfaction was high. A combined femoral-sciatic nerve block is effective in knee arthroplasty. It controls postoperative pain and allows for early rehabilitation. The anterior approach to the sciatic nerve is relatively simple to perform without removing the pressure bandaging from the thigh after surgery. This approach also makes it unnecessary to move the patient.

  15. Electromigration of single metal atoms observed by scanning tunneling microscopy

    NARCIS (Netherlands)

    Braun, K.-F.; Soe, W.H.; Flipse, C.F.J.

    2007-01-01

    The authors show in this letter that single metal atoms on a Ni(111) surface can be pushed by electromigration forces from a scanning tunneling microscope tip. This repulsive interaction is obsd. over a length scale of 6 nm. While for voltages above -300 mV the atoms are pulled by the microscope

  16. Comparison of Radial Access, Guided Femoral Access, and Non-Guided Femoral Access Among Women Undergoing Percutaneous Coronary Intervention.

    Science.gov (United States)

    Koshy, Linda M; Aberle, Laura H; Krucoff, Mitchell W; Hess, Connie N; Mazzaferri, Ernest; Jolly, Sanjit S; Jacobs, Alice; Gibson, C Michael; Mehran, Roxana; Gilchrist, Ian C; Rao, Sunil V

    2018-01-01

    This study was conducted to determine the association between radial access, guided femoral access, and non-guided femoral access on postprocedural bleeding and vascular complications after percutaneous coronary intervention (PCI). Bleeding events and major vascular complications after PCI are associated with increased morbidity, mortality, and cost. While the radial approach has been shown to be superior to the femoral approach in reducing bleeding and vascular complications, whether the use of micropuncture, fluoroscopy, or ultrasound mitigates these differences is unknown. We conducted a post hoc analysis of women in the SAFE-PCI for Women trial who underwent PCI and had the access method identified (n = 643). The primary endpoint of postprocedure bleeding or vascular complications occurring within 72 hours or at discharge was adjudicated by an independent clinical events committee and was compared based on three categories of access technique: radial, guided femoral (fluoroscopy, micropuncture, ultrasound), or non-guided femoral (none of the aforementioned). Differences between the groups were determined using multivariate logistic regression using radial access as the reference. Of the PCI population, 330 underwent radial access, 228 underwent guided femoral access, and 85 underwent non-guided femoral access. There was a statistically significant lower incidence of the primary endpoint with radial access vs non-guided femoral access; however, there was no significant difference between radial approach and femoral access guided by fluoroscopy, micropuncture, or ultrasound. This post hoc analysis demonstrates that while radial access is safer than non-guided femoral access, guided femoral access appears to be associated with similar bleeding events or vascular complications as radial access.

  17. Current indications for open Kuntscher nailing of femoral shaft ...

    African Journals Online (AJOL)

    Current indications for open Kuntscher nailing of femoral shaft fractures. A S Bajwa FCS(SA)ORTH. E Schnaid FCS(SA)ORTH. M E B Sweet MD PhD(rned). University of Witwatersrand, Johannesburg, South Africa. Key Words: Kuntscher nail, intramedullary nail, femoral fracture. We retrospectively reviewed 32 patients with.

  18. Bilateral impacted femoral neck fracture in a renal disease patient ...

    African Journals Online (AJOL)

    Spontaneous bilateral femoral neck facture in a renal disease patient is not common. We report a case of 47-year-old female patient with chronic renal failure and on regular hemodialysis for the past 5 years who sustained bilateral impacted femoral neck fracture without history of trauma and injury and refused any surgical ...

  19. Slipped capital femoral epiphysis: A modern treatment protocol

    Directory of Open Access Journals (Sweden)

    Slavković Nemanja

    2009-01-01

    Full Text Available The treatment of a patient with slipped capital femoral epiphysis begins with an early diagnosis and accurate classification. On the basis of symptom duration, clinical findings and radiographs, slipped capital femoral epiphysis is classified as pre-slip, acute, acute-on-chronic and chronic. The long-term outcome of slipped capital femoral epiphysis is directly related to severity and the presence or absence of avascular necrosis and/or chondrolysis. Therefore, the first priority in the treatment of slipped capital femoral epiphysis is to avoid complications while securing the epiphysis from further slippage. Medical treatment of patients with acute and acute-on-chronic slipped capital femoral epiphysis, as well as those presented in pre-slip stage, is the safest, although time-consuming. Manipulations, especially forced and repeated, are not recommended due to higher avascular necrosis risk. The use of intraoperative fluoroscopy to assist in the placement of internal fixation devices has markedly increased the success of surgical treatment. Controversy remains as to whether the proximal femoral epiphysis in severe, chronic slipped capital femoral epiphysis should be realigned by extracapsular osteotomies or just fixed in situ. The management protocol for slipped capital femoral epiphysis depends on the experience of the surgeon, motivation of the patient and technical facilities.

  20. Femoral neck fractures: A prospective assessment of the pattern ...

    African Journals Online (AJOL)

    OBJECTIVE: To review the pattern of femoral neck fractures, complications and outcome following fixation with Austin-Moore endoprosthesis. METHOD: A two year prospective study in patients who had fracture of the femoral neck based on strict inclusion criteria. All the patients were treated by Austin-Moore ...

  1. Femoral bifurcation with ipsilateral tibia hemimelia: Early outcome of ...

    African Journals Online (AJOL)

    Hereby, we present a case report of a 2-year-old boy who first presented in our orthopedic clinic as a 12-day-old neonate, with a grossly deformed right lower limb from a combination of complete tibia hemimelia and ipsilateral femoral bifurcation. Excision of femoral exostosis, knee disarticulation and prosthetic fitting gives ...

  2. Proximal Focal Femoral Deficiency in Ibadan a Developing ...

    African Journals Online (AJOL)

    The cultural aversion to amputation in our environment makes it difficult to employ that option of treatment. Proximal focal femoral deficiency in Ibadan a developing country's perspective and a review of the literature. Keywords: Proximal focal femoral deficiency , congenital malformations , limb malformations , lower limb ...

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

    Science.gov (United States)

    Minato, Izumi

    2011-03-01

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

  4. Tunneling path toward spintronics

    International Nuclear Information System (INIS)

    Miao Guoxing; Moodera, Jagadeesh S; Muenzenberg, Markus

    2011-01-01

    The phenomenon of quantum tunneling, which was discovered almost a century ago, has led to many subsequent discoveries. One such discovery, spin polarized tunneling, was made 40 years ago by Robert Meservey and Paul Tedrow (Tedrow and Meservey 1971 Phys. Rev. Lett. 26 192), and it has resulted in many fundamental observations and opened up an entirely new field of study. Until the mid-1990s, this field developed at a steady, low rate, after which a huge increase in activity suddenly occurred as a result of the unraveling of successful spin tunneling between two ferromagnets. In the past 15 years, several thousands of papers related to spin polarized tunneling and transport have been published, making this topic one of the hottest areas in condensed matter physics from both fundamental science and applications viewpoints. Many review papers and book chapters have been written in the past decade on this subject. This paper is not exhaustive by any means; rather, the emphases are on recent progress, technological developments and informing the reader about the current direction in which this topic is moving.

  5. Magnetic Fluxtube Tunneling

    Science.gov (United States)

    Dahlburg, Russell B.; Antiochos,, Spiro K.; Norton, D.

    1996-01-01

    We present numerical simulations of the collision and subsequent interaction of two initially orthogonal, twisted, force free field magnetic fluxtubes. The simulations were carried out using a new three dimensional explicit parallelized Fourier collocation algorithm for solving the viscoresistive equations of compressible magnetohydrodynamics. It is found that, under a wide range of conditions, the fluxtubes can 'tunnel' through each other. Two key conditions must be satisfied for tunneling to occur: the magnetic field must be highly twisted with a field line pitch much greater than 1, and the magnetic Lundquist number must be somewhat large, greater than or equal to 2880. This tunneling behavior has not been seen previously in studies of either vortex tube or magnetic fluxtube interactions. An examination of magnetic field lines shows that tunneling is due to a double reconnection mechanism. Initially orthogonal field lines reconnect at two specific locations, exchange interacting sections and 'pass' through each other. The implications of these results for solar and space plasmas are discussed.

  6. Tunnel nitrogen spill experiment

    International Nuclear Information System (INIS)

    Ageyev, A.I.; Alferov, V.N.; Mulholland, G.T.

    1983-01-01

    The Energy Saver Safety Analysis Report (SAR) found the tunnel oxygen deficiency considerations emphasized helium spills. These reports concluded the helium quickly warms and because of its low denisty, rises to the apex of the tunnel. The oxygen content below the apex and in all but the immediate vicinity of the helium spill is essentially unchanged and guarantees an undisturbed source of oxygen especially important to fallen personnel. In contrast nitrogen spills warm slower than helium due to the ratio of the enthalpy changes per unit volume spilled spread more uniformly across the tunnel cross-section when warmed because of the much smaller density difference with air, and generally provides a greater hazard than helium spills as a result. In particular there was concern that personnel that might fall to the floor for oxygen deficiency or other reasons might find less, and not more, oxygen with dire consequences. The SAR concluded tunnel nitrogen spills were under-investigated and led to this work

  7. The scanning tunneling microscope

    International Nuclear Information System (INIS)

    Salvan, F.

    1986-01-01

    A newly conceived microscope, based on a pure quantum phenomenon, is an ideal tool to study atom by atom the topography and properties of surfaces. Applications are presented: surface ''reconstruction'' of silicon, lamellar compound study, etc... Spectroscopy by tunnel effect will bring important information on electronic properties; it is presented with an application on silicon [fr

  8. Supramolecular tunneling junctions

    NARCIS (Netherlands)

    Wimbush, K.S.

    2012-01-01

    In this study a variety of supramolecular tunneling junctions were created. The basis of these junctions was a self-assembled monolayer of heptathioether functionalized ß-cyclodextrin (ßCD) formed on an ultra-flat Au surface, i.e., the bottom electrode. This gave a well-defined hexagonally packed

  9. Epidemiology of metatarsal stress fractures versus tibial and femoral stress fractures during elite training.

    Science.gov (United States)

    Finestone, Aharon; Milgrom, Charles; Wolf, Omer; Petrov, Kaloyan; Evans, Rachel; Moran, Daniel

    2011-01-01

    The training of elite infantry recruits takes a year or more. Stress fractures are known to be endemic in their basic training and the clinical presentation of tibial, femoral, and metatarsal stress fractures are different. Stress fracture incidence during the subsequent progressively more demanding training is not known. The study hypothesis was that after an adaptation period, the incidence of stress fractures during the course of 1 year of elite infantry training would fall in spite of the increasingly demanding training. Seventy-six male elite infantry recruits were followed for the development of stress fractures during a progressively more difficult training program composed of basic training (1 to 14 weeks), advanced training (14 to 26 weeks), and unit training (26 to 52 weeks). Subjects were reviewed regularly and those with clinical suspicion of stress fracture were assessed using bone scan and X-rays. The incidence of stress fractures was 20% during basic training, 14% during advanced training and 23% during unit training. There was a statistically significant difference in the incidence of tibial and femoral stress fractures versus metatarsal stress fractures before and after the completion of phase II training at week 26 (p=0.0001). Seventy-eight percent of the stress fractures during phases I and II training were either tibial or femoral, while 91% of the stress fractures in phase III training were metatarsal. Prior participation in ball sports (p=0.02) and greater tibial length (p=0.05) were protective factors for stress fracture. The study hypothesis that after a period of soldier adaptation, the incidence of stress fractures would decrease in spite of the increasingly demanding elite infantry training was found to be true for tibial and femoral fractures after 6 months of training but not for metatarsal stress fractures. Further studies are required to understand the mechanism of this difference but physicians and others treating stress fractures

  10. Osteosynthesis of femoral neck fractures: dynamic hip screw (DHS or mini-invasive Targon FN system?

    Directory of Open Access Journals (Sweden)

    A. K. Dulaev

    2015-01-01

    Full Text Available Objectives: to investigate the long-term outcomes of femoral neck fractures that were surgically fixed using various types of extramedullary implants in patients aged 65 years and younger. Material and methods: We analyzed the clinical results of surgical treatment of femoral neck fractures by extramedullary osteosynthesis in 94 patients aged 38 to 65 years old (71 women and 23 men. The patients were divided into 3 groups according to AO/ASIF fracture classification. We used different techniques of osteosynthesis: with DHS or with Targon FN. In all patients the mental status rate SPMSQ, osteoporosis degree (Singh index, general somatic status (WHO scale were evaluated in the preoperative period. We also evaluated next intraoperative parameters: duration of surgery, blood loss, quality of reduction, long of incision. In a year after surgery we assessed functional results (Harris Hip Score and analysed postoperative complications. Results: It was found the inverse correlation (r = -0,8 of total preoperative parameters (WHO scale, the Singh index and mental status SPMSQ and postoperative functional results on Harris Hip Score. With the reliability of p<0.05 the average rate of blood loss and length of skin incision were less in patients operated with Targon FN. In 12 months unsatisfactory results rate on Harris Hip Score was 12.7% in all study groups, great - 22,3%, good - 52.1%, and satisfactory - 12,9%. Complications rate in patients operated with DHS was 17,02%, and in patients operated with Targon FN - 18.1%. Conclusion: Minimally invasive osteosynthesis of femoral neck fractures (type B1 and B2 on AO/ASIF classification allows to achieve the best results in compare with DHS osteosynthesis. Revealed complications such as screw migration, false joint formation and femoral head avascular necrosis were determined by impaired surgical technique and inadequate reduction.

  11. Transfracture abduction osteotomy: A solution for nonunion of femoral neck fractures

    Directory of Open Access Journals (Sweden)

    Jairamchander Pingle

    2014-01-01

    femur with or without bone graft, valgus osteotomy or hip arthroplasty. We conducted a retrospective analysis of cases of nonunion of femoral neck fracture treated by transfracture abduction osteotomy (TFAO. Materials and Methods: Over a period of 35 years (1974-2008, 30 patients with nonunion of femoral neck fractures were treated with TFAO over a period of 35 years (1974-2008, All patients were less than 50 years of age. Absence of clinical and radiological signs of union after four months was considered as nonunion. Patients more than 50 years of age were excluded from the study. Union was assessed at 6 months radiologically. Limb length was measured at six months. The mean duration of femoral neck fracture was 19 months (range 4 months 10 years. Results were analyzed in terms of radiological union at six months. Average followup was five years and six months. Results: Consistent union was noted at the followup after six months in 29 cases. One case was lost to followup after five and one-half months postoperatively. However, the fracture had united in this case at the last followup. Average shortening of the limb at six months was 1.9 cm. Average neck shaft angle was 127° (range 120-145°. Five cases went into AVN but were asymptomatic. Two cases required reoperation due to back out of Moore′s pins. These were reopened and cancellous screws were inserted in the same tracks. Conclusions: Consistent union of nonunion femoral neck fracture was noted at the followup after six months in 29 cases. The major drawback of the procedure is immobilization of the patient in the hip spica for eight weeks.

  12. Magnetic resonance imaging of the femoral head necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Shinya; Asada, Kanji; Yoshida, Kenjiro and others

    1986-06-01

    Ten patients with avascular femoral head necrosis and four normal adults were examined by magnetic resonance imaging (MRI). In addition, the relationship between MRI and pathophysiology of three operated-on avascular femoral heads was evaluated. The medullary cavities of the normal femoral heads had a strong signal intensity on the saturation recovery (SR) image due to fat marrow, and the T/sub 1/ relaxation time was 160 +- 11 msec. In avascular femoral head necrosis, the necrotic area had a low signal intensity on the SR image and a prolonged T/sub 1/ relaxation time, while the reactive fibrous area had more prolonged T/sub 1/ relaxation time. For these reasons, MRI was found to show the pathological changes of avascular femoral head necrosis and can be expected to be useful for making early diagnoses and operation planning.

  13. Magnetic resonance imaging of the femoral head necrosis

    International Nuclear Information System (INIS)

    Narita, Shinya; Asada, Kanji; Yoshida, Kenjiro

    1986-01-01

    Ten patients with avascular femoral head necrosis and four normal adults were examined by magnetic resonance imaging (MRI). In addition, the relationship between MRI and pathophysiology of three operated-on avascular femoral heads was evaluated. The medullary cavities of the normal femoral heads had a strong signal intensity on the saturation recovery (SR) image due to fat marrow, and the T 1 relaxation time was 160 ± 11 msec. In avascular femoral head necrosis, the necrotic area had a low signal intensity on the SR image and a prolonged T 1 relaxation time, while the reactive fibrous area had more prolonged T 1 relaxation time. For these reasons, MRI was found to show the pathological changes of avascular femoral head necrosis and can be expected to be useful for making early diagnoses and operation planning. (author)

  14. Monitoring pilot projects on bored tunnelling : The Second Heinenoord Tunnel and the Botlek Rail Tunnel

    NARCIS (Netherlands)

    Bakker, K.J.; De Boer, F.; Admiraal, J.B.M.; Van Jaarsveld, E.P.

    1999-01-01

    Two pilot projects for bored tunnelling in soft soil have been undertaken in the Netherlands. The monitoring was commissioned under the authority of the Centre for Underground Construction (COB). A description of the research related to the Second Heinenoord Tunnel and the Botlek Rail Tunnel will be

  15. Outcomes of trochanteric femoral fractures treated with proximal femoral nail: an analysis of 100 consecutive cases

    Directory of Open Access Journals (Sweden)

    Korkmaz MF

    2014-04-01

    Full Text Available Mehmet Fatih Korkmaz,1 Mehmet Nuri Erdem,2 Zeliha Disli,3 Engin Burak Selcuk,4 Mustafa Karakaplan,1 Abdullah Gogus5 1Department of Orthopedics and Traumatology, Inonu University School of Medicine, Malatya, Turkey; 2Department of Orthopedics and Traumatology, Nisantasi University School of Medicine, Istanbul, Turkey; 3Department of Anesthesiology, Malatya Government Hospital, Malatya, Turkey; 4Department of Family Medicine, Inonu University School of Medicine, Malatya, Turkey; 5Department of Orthopedics and Traumatology, Florence Nightingale Hospital, Istanbul, Turkey Purpose: In this study, we aimed to report the results of a retrospective study carried out at our institute regarding cases of patients who had suffered proximal femoral fractures between January 2002 and February 2007, and who were treated with a proximal femoral nail. Materials and methods: One hundred consecutive cases were included in the study. A case documentation form was used to obtain intraoperative data including age, sex, mechanism of injury, type of fracture according to Association for Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF classification and the American Society of Anesthesiologists' (ASA physical status classification (ASA grade. Clinical and radiographic examinations were performed at the time of admission and at the 6th week; subsequent visits were organized on the 3rd month, 6th month, and 12th month, and in patients with longer follow-up and annually postoperatively. The Harris score of hip function was used, and any change in the position of the implants and the progress of the fracture union, which was determined radiologically, was noted. Results: The mean age of the patients was 77.66 years (range: 37–98 years, and the sex distribution was 32 males and 68 females. Seventy-three fractures were reduced by closed means, whereas 27 needed limited open reduction. The mean follow-up time for the study group was 31.3 months (range

  16. Measuring fire size in tunnels

    International Nuclear Information System (INIS)

    Guo, Xiaoping; Zhang, Qihui

    2013-01-01

    A new measure of fire size Q′ has been introduced in longitudinally ventilated tunnel as the ratio of flame height to the height of tunnel. The analysis in this article has shown that Q′ controls both the critical velocity and the maximum ceiling temperature in the tunnel. Before the fire flame reaches tunnel ceiling (Q′ 1.0), Fr approaches a constant value. This is also a well-known phenomenon in large tunnel fires. Tunnel ceiling temperature shows the opposite trend. Before the fire flame reaches the ceiling, it increases very slowly with the fire size. Once the flame has hit the ceiling of tunnel, temperature rises rapidly with Q′. The good agreement between the current prediction and three different sets of experimental data has demonstrated that the theory has correctly modelled the relation among the heat release rate of fire, ventilation flow and the height of tunnel. From design point of view, the theoretical maximum of critical velocity for a given tunnel can help to prevent oversized ventilation system. -- Highlights: • Fire sizing is an important safety measure in tunnel design. • New measure of fire size a function of HRR of fire, tunnel height and ventilation. • The measure can identify large and small fires. • The characteristics of different fire are consistent with observation in real fires

  17. Repeat LISS treatment for femoral shaft fractures due to hardware failure: a retrospective analysis of eleven cases.

    Science.gov (United States)

    Li, Xu; Xu, Xian; Liu, Lin; Shao, Qin; Wu, Wei

    2013-10-01

    To evaluate the effectiveness of a replating technique having a less-invasive stabilization system (LISS) for femoral shaft fractures due to LISS failure in adults. There were 11 patients with hardware failure of LISS for femoral shaft fractures, on an average of 50 days after the primary operation. The failed implants were removed, and the fractures were replated with a LISS following the rationale of biological osteosynthesis. Radiological fracture union and incidence of postoperative complications were employed to evaluate the effectiveness of this replating technique for femoral shaft fractures. Operative duration including removing failed hardware and replating fractures averaged 81.5 min, with an average blood loss of 330 ml. Patients had an average follow-up of 25.7 months. Radiological evaluation indicated that fracture union occurred in an average of 4.4 months in all patients. The length and alignment of the affected limb were satisfactory, and hardware failure did not recur. The replating technique with LISS for femoral shaft fractures due to hardware failure of LISS can obtain satisfactory results when the appropriate rationale of biological osteosynthesis and functional exercise is followed.

  18. 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.

  19. Rock mass seismic imaging around the ONKALO tunnel, Olkiluoto 2007

    International Nuclear Information System (INIS)

    Cosma, C.; Cozma, M.; Balu, L.; Enescu, N.

    2008-11-01

    Posiva Oy prepares for disposal of spent nuclear fuel in bedrock focusing in Olkiluoto, Eurajoki. This is in accordance of the application filed in 1999, the Decision-in-Principle of the State Council in 2000, and ratification by the Parliament in 2001. Vibrometric Oy has performed a tunnel seismic survey in ONKALO access tunnel on a 100 m line in December 2007. Tunnel length (chainage) was 1720 - 1820 m (vertical depth 170 - 180 m). Measurement applied 120 source positions at 1 m spacing, and on the both ends at 4 m spacing. Electromechanical Vibsist-20 tool was used as the source. Hammer produced 15.36 s sweeps. Signal was recorded with 2-component geophone assemblies, installed in 400 mm long, 45 mm drillholes in the tunnel wall. Sweeps were recorded with Summit II seismograph and decoded to seismic traces. Also percussion drill rig, which is used in drilling the blasting holes in tunnel excavation, was tested from a 100-m distance as a seismic source. Signal is equally good as from actual seismic source, and may be applied later on for production. Obtained seismic results were processed with tomographic reconstruction of the first arrivals to P and S wave refraction tomograms, and to tomograms of Young's modulus and Shear Modulus. The obtained values correspond the typical levels known from Olkiluoto. There are indications of lower velocity near tunnel wall, but resolution is not adequate for further interpretation. Some variation of velocity is detected in the rock mass. Seismic data was also processed with normal reflection profile interpretation and migrated. As a result there was obtained reflection images to a 100-m distance from the tunnel. Several reflecting events were observed in the rock mass. Features making an angle of 30 deg or more with tunnel axis can be imaged from distances of tens of metres. Vertical fractures perpendicular to tunnel can be imaged only near the tunnel. Gently dipping features can be imaged below and above. Images are 2D, i

  20. The difference in centre position in the ACL femoral footprint inclusive and exclusive of the fan-like extension fibres.

    Science.gov (United States)

    Iriuchishima, Takanori; Ryu, Keinosuke; Aizawa, Shin; Fu, Freddie H

    2016-01-01

    The purpose of this study was to compare the centre position of each anterior cruciate ligament bundle in its femoral footprint in measurements including and excluding the fan-like extension fibres. Fourteen non-paired human cadaver knees were used. All soft tissues around the knee were resected except the ligaments. The ACL was divided into antero-medial (AM) and postero-lateral (PL) bundles according to the difference in tension patterns. The ACL was carefully dissected, and two outlines were made of the periphery of each bundle insertion site: those which included and those which excluded the fan-like extension fibres. An accurate lateral view of the femoral condyle was photographed with a digital camera, and the images were downloaded to a personal computer. The centre position of each bundle, including and excluding the fan-like extension fibres, was measured with ImageJ software (National Institution of Health). Evaluation of the centre position was performed using the modified quadrant method. The centre of the femoral AM bundle including the fan-like extension was located at 28.8% in a shallow-deep direction and 37.2% in a high-low direction. When the AM bundle was evaluated without the fan-like extension, the centre was significantly different at 34.6% in a shallow-deep direction (p = 0.000) and 36% in a high-low direction. The centre of the PL bundle including the fan-like extension was found at 37.1% in a shallow-deep direction and 73.4% in a high-low direction. When the PL bundle was evaluated without the fan-like extension, the centre was significantly different at 42.7% in a shallow-deep direction (p = 0.000) and 69.3% in a high-low direction (p = 0.000). The centre position of the AM and PL bundles in the femoral ACL footprint was significantly different depending on the inclusion or exclusion of the fan-like extension fibres. For the clinical relevance, to reproduce the direct femoral insertion in the anatomical ACL reconstruction, tunnels should be

  1. Outcomes of trochanteric femoral fractures treated with proximal femoral nail: an analysis of 100 consecutive cases.

    Science.gov (United States)

    Korkmaz, Mehmet Fatih; Erdem, Mehmet Nuri; Disli, Zeliha; Selcuk, Engin Burak; Karakaplan, Mustafa; Gogus, Abdullah

    2014-01-01

    In this study, we aimed to report the results of a retrospective study carried out at our institute regarding cases of patients who had suffered proximal femoral fractures between January 2002 and February 2007, and who were treated with a proximal femoral nail. One hundred consecutive cases were included in the study. A case documentation form was used to obtain intraoperative data including age, sex, mechanism of injury, type of fracture according to Association for Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF) classification and the American Society of Anesthesiologists' (ASA) physical status classification (ASA grade). Clinical and radiographic examinations were performed at the time of admission and at the 6th week; subsequent visits were organized on the 3rd month, 6th month, and 12th month, and in patients with longer follow-up and annually postoperatively. The Harris score of hip function was used, and any change in the position of the implants and the progress of the fracture union, which was determined radiologically, was noted. The mean age of the patients was 77.66 years (range: 37-98 years), and the sex distribution was 32 males and 68 females. Seventy-three fractures were reduced by closed means, whereas 27 needed limited open reduction. The mean follow-up time for the study group was 31.3 months (range: 12-75 months). Postoperative radiographs showed a near-anatomical fracture reduction in 78% of patients. The Harris hip score was negatively correlated with the ASA score and patient age. No cases of implant failure were observed. Three patients died before discharge (one due to pulmonary embolism, two due to cardiac arrest), and five patients died due to unrelated medical conditions within the first 3 months of the follow-up. Our study showed that proximal femoral nail is a reliable fixation with good fracture union, and it is not associated with major complications in any type of trochanteric femoral fracture.

  2. Avascular necrosis of the femoral head after osteosynthesis of femoral neck fracture.

    Science.gov (United States)

    Min, Byung-Woo; Kim, Sung-Jin

    2011-05-18

    The reported incidence of avascular necrosis after femoral neck fracture fixation varies widely, and there is no consensus regarding its risk factors. We evaluated the incidence of avascular necrosis of the femoral head with the use of contemporary techniques for femoral neck fracture fixation. We then sought to determine what potential risk factors influenced the development of avascular necrosis.Between 1990 and 2005, one hundred sixty-three intracapsular femoral neck fractures in 163 patients were treated with internal fixation at our level-I trauma center. All patients were monitored until conversion to total hip arthroplasty or for a minimum of 2 years postoperatively. Ten patients (10 hips) died and 7 patients (7 hips) were lost to follow-up. The remaining 146 patients (146 hips) had a mean 5.2 years of follow-up (range, 3 months to 17 years). The incidence of avascular necrosis was 25.3% (37 hips). The average time to diagnosis of avascular necrosis was 18.8 months (range, 3-47 months). Patient sex, age, interval from injury to surgery, and mechanism of injury were statistically not associated with the development of avascular necrosis. The quality of fracture reduction, adequacy of fixation, degree of displacement, and comminution of the posterior cortex were significantly associated. After we controlled for patient and radiographic characteristics, multivariate analyses indicated that the important predictors for avascular necrosis are poor reduction (odds ratio=13.889) and initial displacement of the fracture (odds ratio=4.693). Copyright 2011, SLACK Incorporated.

  3. Analysis of slipped capital femoral epiphysis

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Sponseller, P.D.; Griffin, P.P.

    1988-01-01

    CT with multiplanar reconstruction (CT/MPR) was used to assess 25 adolescents with known or suspected slipped capital femoral epiphysis (SCFE). CT/MPR localizes the epiphysis in three planes, establishing its relationship to the acetabulum and the metaphyseal neck. MPR facilitates measurements of head-neck angles, residusal head-neck contact, and relative retrovision. CT/MPR may establish the true age of the epiphyseal failure and can reveal subtle SCFE in the face of normal plain films. Patients often present with confusing histories; clues to the true age of failure include subtle signs of healing, remodeling, or new bone buttressing. Characterization of acute versus chronic conditions influences preoperative planning. Postoperatively, CT/MPR confirms early results and follows epiphyseal fusion and remodelling. It also detects complications, such as pin or graft migration avascular necrosis (AVN), or chondrolysis

  4. Femoral neck buttressing: a radiographic and histologic analysis

    International Nuclear Information System (INIS)

    Dixon, T.; Benjamin, J.; Lund, P.; Graham, A.; Krupinski, E.

    2000-01-01

    Objective. To examine the incidence, radiographic and histologic findings of medial femoral neck buttressing in a consecutive group of patients undergoing total hip arthroplasty.Design. Biomechanical parameters were evaluated on standard anteroposterior pelvic radiographs of 113 patients prior to hip replacement surgery. Demographic information on all patients was reviewed and histologic evaluation was performed on specimens obtained at the time of surgery.Results. The incidence of medial femoral neck buttressing was found to be 50% in a consecutive series of patients undergoing total hip arthroplasty. The incidence was slightly higher in women (56% vs 41%). Patients with buttressing had increased neck-shaft angles and smaller femoral neck diameters than were seen in patients without buttressing. Histologic evaluation demonstrated that the buttress resulted from deposition bone by the periosteum on the femoral neck in the absence of any evidence of femoral neck fracture.Conclusion. It would appear that femoral neck buttressing occurs in response to increased joint reactive forces seen at the hip being transmitted through the femoral neck. The increased joint reactive force can be related to the increased neck shaft angle seen in patients with buttressing. (orig.)

  5. Clinical study on 44 cases of femoral hernia

    International Nuclear Information System (INIS)

    Yamamoto, Ryo; Shinozaki, Hiroharu; Kase, Kenichi; Kobayashi, Kenji; Sasaki, Junichi

    2012-01-01

    Femoral hernia is a surgical disease that is frequently associated with incarceration and necessitates emergency surgery. However, there are only a few studies referred which have compared emergency and elective surgery for femoral hernias. We retrospectively reviewed the clinical characteristics of patients diagnosed as having femoral hernia between 2005 and 2009 in our institution. The clinical features of emergency repairs were compared with those of elective ones, and diagnostic values of preoperative diagnostic modalities were studied. The mean age of the patients was 73±12 years. Females comprised 68% of the cases, and right femoral hernias comprised 70% of the cases. Incarceration was associated with 66% of the cases (29 patients), and emergency surgery was performed in 52% of the patients (23 patients). Bowel resection was performed in 32% of the cases (14 patients). The mean age, body temperature, white blood cell (WBC) count, and LDH value were higher in the emergency repairs than in the elective one, and most of the hernias were repaired with McVay's procedure. CT scans had a high diagnostic value in detecting femoral hernias (44%) and incarceration (88%). It was confirmed that femoral hernias were frequently associated with incarceration and CT scan has a high diagnostic value in femoral hernias. (author)

  6. Simultaneous avascular necrosis of both medial and lateral femoral condyles

    International Nuclear Information System (INIS)

    Mansberg, R.

    2002-01-01

    Full text: Avascular necrosis (AVN) of a femoral condyle is a common orthopaedic condition. While both medial and lateral femoral condyles may be involved either singly or sequentially the simultaneous occurrence of AVN of both femoral condyles is extremely uncommon. A 57-year-old male is presented who developed the onset of severe left sided knee pain suddenly at rest. Plain and tomographic radiography was unremarkable and a bone scan was performed. Markedly increased vascularity was demonstrated in the left knee with intense osteoblastic activity in the left medial and femoral condyles more marked in the lateral femoral condyle. A diagnosis of AVN of both femoral condyles was made and a MRI exam was performed to confirm this unusual diagnosis. The MRI showed a diffuse increase in intensity bilaterally with subtle bony change in the subarticular bone consistent with AVN more marked in the left lateral femoral condyle. The patients' symptoms resolved with supportive treatment. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  7. Tunnel boring machine applications

    International Nuclear Information System (INIS)

    Bhattacharyya, K.K.; McDonald, R.; Saunders, R.S.

    1992-01-01

    This paper reports that characterization of Yucca Mountain for a potential repository requires construction of an underground Exploratory Studies Facility (ESF). Mechanical excavating methods have been proposed for construction of the ESF as they offer a number of advantages over drilling and blasting at the Yucca Mountain site, including; less ground disturbance and therefore a potential for less adverse effects on the integrity of the site, creation of a more stable excavation cross section requiring less ground support, and an inherently safer and cleaner working environment. The tunnel boring machine (TBM) provides a proven technology for excavating the welded and unwelded Yucca Mountain tuffs. The access ramps and main underground tunnels form the largest part of the ESF underground construction work, and have been designed for excavation by TBM

  8. Programmable ferroelectric tunnel memristor

    Directory of Open Access Journals (Sweden)

    Andy eQuindeau

    2014-02-01

    Full Text Available We report an analogously programmable memristor based on genuine electronic resistive switching combining ferroelectric switching and electron tunneling. The tunnel current through an 8 unit cell thick epitaxial Pb(Zr[0.2]Ti[0.8]O[3] film sandwiched between La[0.7]Sr[0.3]MnO[3] and cobalt electrodes obeys the Kolmogorov-Avrami-Ishibashi model for bidimensional growth with a characteristic switching time in the order of 10^-7 seconds. The analytical description of switching kinetics allows us to develop a characteristic transfer function that has only one parameter viz. the characteristic switching time and fully predicts the resistive states of this type of memristor.

  9. Electric and VLF-MT survey of Tegatayama tunnel; Tegatayama tunnel no denki tansa oyobi VLF tansa

    Energy Technology Data Exchange (ETDEWEB)

    Nishitani, T [Akita University, Akita (Japan). Mining College

    1997-05-27

    To survey the structure at the depth between 20 and 30 m, field tests were conducted by means of vertical electric and VFL-MT (magnetotelluric) survey. Tegatayama tunnel has a total length of 276 m, width of 7.5 m, and height of 4.7 m, and the depth from the surface is about 28 m near the top of mountain. Near the tunnel, the thickness of surface soil is about 60 cm, which consists of clay soil including soft mudstone gravel. It was found that terrace deposit is distributed up to the depth of 8 m, and that mudstone is distributed below the depth of 8 m. Weighted four-electrode method was adopted for the vertical electrical survey. Measurements were conducted at the immediately above the tunnel, 10 m apart from the center of tunnel in the right and left, and 20 m apart from the center in the east. For the VLF-MT method, component of frequency 22.2 kHz was used. As a result of the tests, it was difficult to illustrate the existence of tunnel from the vertical electrical survey only at one point. Feature of the tunnel could be well illustrated by means of the VLF-MT method. 3 refs., 9 figs.

  10. Hawking Radiation As Tunneling

    International Nuclear Information System (INIS)

    Parikh, Maulik K.; Wilczek, Frank

    2000-01-01

    We present a short and direct derivation of Hawking radiation as a tunneling process, based on particles in a dynamical geometry. The imaginary part of the action for the classically forbidden process is related to the Boltzmann factor for emission at the Hawking temperature. Because the derivation respects conservation laws, the exact spectrum is not precisely thermal. We compare and contrast the problem of spontaneous emission of charged particles from a charged conductor

  11. Tunnel blasting - recent developments

    Energy Technology Data Exchange (ETDEWEB)

    White, T.E.

    1999-05-01

    While tunnelling machines are more efficient than previously, there are still areas where blasting is a more efficient method of advance. Drilling and design methods are increasingly sophisticated, as is choice of explosive. Explosive deployment must be carefully calculated so as to avoid desensitisation. Nitroglycerine may be used as slurries; bulk mixing on site of ANFO is also practised in mining in the UK. Electric detonators, Nonel tubes, and electronic detonators are also increasingly employed.

  12. The beam dump tunnels

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    In these images workers are digging the tunnels that will be used to dump the counter-circulating beams. Travelling just a fraction under the speed of light, the beams at the LHC will each carry the energy of an aircraft carrier travelling at 12 knots. In order to dispose of these beams safely, a beam dump is used to extract the beam and diffuse it before it collides with a radiation shielded graphite target.

  13. Primary Tunnel Junction Thermometry

    International Nuclear Information System (INIS)

    Pekola, Jukka P.; Holmqvist, Tommy; Meschke, Matthias

    2008-01-01

    We describe the concept and experimental demonstration of primary thermometry based on a four-probe measurement of a single tunnel junction embedded within four arrays of junctions. We show that in this configuration random sample specific and environment-related errors can be avoided. This method relates temperature directly to Boltzmann constant, which will form the basis of the definition of temperature and realization of official temperature scales in the future

  14. Hydrodynamic optical soliton tunneling

    Science.gov (United States)

    Sprenger, P.; Hoefer, M. A.; El, G. A.

    2018-03-01

    A notion of hydrodynamic optical soliton tunneling is introduced in which a dark soliton is incident upon an evolving, broad potential barrier that arises from an appropriate variation of the input signal. The barriers considered include smooth rarefaction waves and highly oscillatory dispersive shock waves. Both the soliton and the barrier satisfy the same one-dimensional defocusing nonlinear Schrödinger (NLS) equation, which admits a convenient dispersive hydrodynamic interpretation. Under the scale separation assumption of nonlinear wave (Whitham) modulation theory, the highly nontrivial nonlinear interaction between the soliton and the evolving hydrodynamic barrier is described in terms of self-similar, simple wave solutions to an asymptotic reduction of the Whitham-NLS partial differential equations. One of the Riemann invariants of the reduced modulation system determines the characteristics of a soliton interacting with a mean flow that results in soliton tunneling or trapping. Another Riemann invariant yields the tunneled soliton's phase shift due to hydrodynamic interaction. Soliton interaction with hydrodynamic barriers gives rise to effects that include reversal of the soliton propagation direction and spontaneous soliton cavitation, which further suggest possible methods of dark soliton control in optical fibers.

  15. Resonant Tunneling Spin Pump

    Science.gov (United States)

    Ting, David Z.

    2007-01-01

    The resonant tunneling spin pump is a proposed semiconductor device that would generate spin-polarized electron currents. The resonant tunneling spin pump would be a purely electrical device in the sense that it would not contain any magnetic material and would not rely on an applied magnetic field. Also, unlike prior sources of spin-polarized electron currents, the proposed device would not depend on a source of circularly polarized light. The proposed semiconductor electron-spin filters would exploit the Rashba effect, which can induce energy splitting in what would otherwise be degenerate quantum states, caused by a spin-orbit interaction in conjunction with a structural-inversion asymmetry in the presence of interfacial electric fields in a semiconductor heterostructure. The magnitude of the energy split is proportional to the electron wave number. Theoretical studies have suggested the possibility of devices in which electron energy states would be split by the Rashba effect and spin-polarized currents would be extracted by resonant quantum-mechanical tunneling.

  16. Telomere length analysis.

    Science.gov (United States)

    Canela, Andrés; Klatt, Peter; Blasco, María A

    2007-01-01

    Most somatic cells of long-lived species undergo telomere shortening throughout life. Critically short telomeres trigger loss of cell viability in tissues, which has been related to alteration of tissue function and loss of regenerative capabilities in aging and aging-related diseases. Hence, telomere length is an important biomarker for aging and can be used in the prognosis of aging diseases. These facts highlight the importance of developing methods for telomere length determination that can be employed to evaluate telomere length during the human aging process. Telomere length quantification methods have improved greatly in accuracy and sensitivity since the development of the conventional telomeric Southern blot. Here, we describe the different methodologies recently developed for telomere length quantification, as well as their potential applications for human aging studies.

  17. Excitation of propagating surface plasmons with a scanning tunnelling microscope.

    Science.gov (United States)

    Wang, T; Boer-Duchemin, E; Zhang, Y; Comtet, G; Dujardin, G

    2011-04-29

    Inelastic electron tunnelling excitation of propagating surface plasmon polaritons (SPPs) on a thin gold film is demonstrated. This is done by combining a scanning tunnelling microscope (STM) with an inverted optical microscope. Analysis of the leakage radiation in both the image and Fourier planes unambiguously shows that the majority (up to 99.5%) of the detected photons originate from propagating SPPs with propagation lengths of the order of 10  µm. The remaining photon emission is localized under the STM tip and is attributed to a tip-gold film coupled plasmon resonance as evidenced by the bimodal spectral distribution and enhanced emission intensity observed using a silver STM tip for excitation.

  18. Ipsilateral femoral shaft and vertical patella fracture: a case report

    Science.gov (United States)

    Ozkan, Korhan; Eceviz, Engin; Sahin, Adem; Ugutmen, Ender

    2009-01-01

    Introduction A femoral shaft fracture with an ipsilateral patella fracture has been, to our knowledge, given only cursory attention in English-speaking literature. Case presentation A 15 year old male patient had hitten by a car to his motorcycle came to emergency room and he had been operated for his femoral shaft freacture and vertical patellar fracture which was iniatally missed. Conclusion To us it is vital to obtain CT scan of the patient’s knee if there is an ipsilateral femoral fracture with an ipsilateral knee effusion and a punction which reveals hematoma even in the absence of a fracture line seen in AP and lateral projections. PMID:19829933

  19. Avascular osteonecrosis of the femoral condyle after arthroscopic surgery

    International Nuclear Information System (INIS)

    Al-Kaar, M.; Garcia, J.; Fritschy, D.; Bonvin, J.C.

    1997-01-01

    Avascular osteonecrosis of the femoral condyle after arthroscopic surgery. Retrospective review of 10 patients who presented with avascular necrosis of the ipsilateral femoral condyle following arthroscopic meniscectomy (9 medial, 1 lateral). The bone lesions were evaluated by radiography and MRI, which were repeated for few patients. MRI allows earlier diagnosis of avascular necrosis of the femoral condyle and offers an evaluation of extent of the lesions whose evolution is variable: 3 patients required a knee prosthesis, the other 7 patients were treated medically. (authors)

  20. Femoral artery pseudoaneurysm as a complication of angioplasty. How can it be prevented?

    Science.gov (United States)

    Gupta, Prabha Nini; Salam Basheer, Abdul; Sukumaran, Gireesh Gomaty; Padmajan, Sabin; Praveen, Satheesan; Velappan, Praveen; Nair, Bigesh Unnikrishnan; Nair, Sandeep Govindan; Kunjuraman, Usha Kumari; Madthipat, Unnikrishnan; R, Jayadevan

    2013-01-01

    Femoral pseudoaneurysm is a common complication of repeated femoral puncture during cardiac catheterisation. We describe here the development of femoral pseudoaneurysms in a patient with Takayasu's arteritis, which healed in response to conservative treatment, and review the literature on the prevention and treatment of femoral pseudoaneurysm. PMID:27326111

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

    Science.gov (United States)

    Kong, Heather; Sabharwal, Sanjeev

    2014-12-01

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

  2. Submucosal tunneling techniques: current perspectives.

    Science.gov (United States)

    Kobara, Hideki; Mori, Hirohito; Rafiq, Kazi; Fujihara, Shintaro; Nishiyama, Noriko; Ayaki, Maki; Yachida, Tatsuo; Matsunaga, Tae; Tani, Johji; Miyoshi, Hisaaki; Yoneyama, Hirohito; Morishita, Asahiro; Oryu, Makoto; Iwama, Hisakazu; Masaki, Tsutomu

    2014-01-01

    Advances in endoscopic submucosal dissection include a submucosal tunneling technique, involving the introduction of tunnels into the submucosa. These tunnels permit safer offset entry into the peritoneal cavity for natural orifice transluminal endoscopic surgery. Technical advantages include the visual identification of the layers of the gut, blood vessels, and subepithelial tumors. The creation of a mucosal flap that minimizes air and fluid leakage into the extraluminal cavity can enhance the safety and efficacy of surgery. This submucosal tunneling technique was adapted for esophageal myotomy, culminating in its application to patients with achalasia. This method, known as per oral endoscopic myotomy, has opened up the new discipline of submucosal endoscopic surgery. Other clinical applications of the submucosal tunneling technique include its use in the removal of gastrointestinal subepithelial tumors and endomicroscopy for the diagnosis of functional and motility disorders. This review suggests that the submucosal tunneling technique, involving a mucosal safety flap, can have potential values for future endoscopic developments.

  3. Recent development in the design of hard rock tunnel boring machines for the mining industry

    International Nuclear Information System (INIS)

    Snyder, L.L.; Williams, R.I.

    1991-01-01

    Underground development for nuclear waste storage will possibly require tunnels to be excavated in a variety of rock conditions and configurations. Recent innovations in Tunnel Boring Machine (TBM) design have allowed for an evolved style of TBM which has distinct advantages over the standard machines. Present day conventional hard rock TBM's were developed primarily for the long, relatively straight tunnels of the civil construction industry, thereby making them for the most part, unsuitable for the sharp curves, turnouts, declines, inclines and ramps required in many underground environments. The five foot to 36 foot (1.52 to 11 m) diameter machines are capable of boring tunnels with curve radiuses as small as 40 to 90 feet (12.2 to 27.5 m) depending on size. These short turning radiuses can be accomplished while gripping the tunnel walls horizontally in the traditional manner or vertically as required when intersecting existing tunnels, or making turnouts from the tunnel that the machine has just bored. The machine's length is approximately half of a traditional machine's length while still employing a full measure of thrust, horsepower and rock cutting ability. The machine's short length, combined with a patented machine structure allows it to steer while boring without causing harmful eccentric loads on the cutterhead and main bearing assembly. The machine configuration is versatile and can be easily modified to operate in a wide variety of conditions

  4. Avascular osteonecrosis of the femoral condyle after arthroscopic surgery; Osteonecrose aseptique du condyle femoral apres meniscectomie par voie arthroscopique

    Energy Technology Data Exchange (ETDEWEB)

    Al-Kaar, M.; Garcia, J. [Hopital Cantonal Geneve, Geneva (Switzerland); Fritschy, D.; Bonvin, J.C. [Policlinique de Chirurgie, Hopital Cantonal Universitaire, Geneve (Switzerland)

    1997-04-01

    Avascular osteonecrosis of the femoral condyle after arthroscopic surgery. Retrospective review of 10 patients who presented with avascular necrosis of the ipsilateral femoral condyle following arthroscopic meniscectomy (9 medial, 1 lateral). The bone lesions were evaluated by radiography and MRI, which were repeated for few patients. MRI allows earlier diagnosis of avascular necrosis of the femoral condyle and offers an evaluation of extent of the lesions whose evolution is variable: 3 patients required a knee prosthesis, the other 7 patients were treated medically. (authors). 21 refs.

  5. Semiclassical description of resonant tunneling

    International Nuclear Information System (INIS)

    Bogomolny, E.B.; Rouben, D.C.

    1996-01-01

    A semiclassical formula is calculated for the tunneling current of electrons trapped in a potential well which can tunnel into and across a wide quantum well. The tunneling current is measured at the second interface of this well and the calculations idealized an experimental situation where a strong magnetic field tilted with respect to an electric field was used. It is shown that the contribution to the tunneling current, due to trajectories which begin at the first interface and end on the second, is dominant for periodic orbits which hit both walls of the quantum well. (author)

  6. early functional outcome of distal femoral fractures at kenyatta

    African Journals Online (AJOL)

    The leading cause was RTA, followed by falls from a height. ... Distal femoral fractures cause considerable morbidity .... as means and standard deviations. .... Anaesthesia. Spinal. 37 (80). General Anaesthesia (GA). 9 (20). Transfusion.

  7. Femoral neck fractures complicating gaucher disease in children

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, A.B.; Jacobs, B.

    1984-09-01

    In normal children, fractures of the femoral neck are uncommon and accompany severe trauma and multiple injuries elsewhere in the skeleton. In children with Gaucher disease, a rare hereditary disorder of lipid metabolism, midcervical or basicervical fractures can occur with minor or no trauma and without other injury to the skeleton. Three children with Gaucher disease who developed pathologic fractures of the femoral neck are described. In all three, the fractures occurred between five and nine years of age, and the fracture lines passed through areas of abnormal bone characterized by poorly defined patches of increased and decreased density and cortical thinning along the medial femoral necks. In the affected hips, there was no evidence of avascular necrosis of the femoral heads at the time of injury. One child's fracture was preceeded by multiple bone 'crisis' localized to the proximal femora.

  8. Femoral neck fractures complicating gaucher disease in children

    International Nuclear Information System (INIS)

    Goldman, A.B.; Jacobs, B.

    1984-01-01

    In normal children, fractures of the femoral neck are uncommon and accompany severe trauma and multiple injuries elsewhere in the skeleton. In children with Gaucher disease, a rare hereditary disorder of lipid metabolism, midcervical or basicervical fractures can occur with minor or no trauma and without other injury to the skeleton. Three children with Gaucher disease who developed pathologic fractures of the femoral neck are described. In all three, the fractures occurred between five and nine years of age, and the fracture lines passed through areas of abnormal bone characterized by poorly defined patches of increased and decreased density and cortical thinning along the medial femoral necks. In the affected hips, there was no evidence of avascular necrosis of the femoral heads at the time of injury. One child's fracture was preceeded by multiple bone 'crisis' localized to the proximal femora. (orig.)

  9. Effectiveness of plate augmentation for femoral shaft nonunion after nailing

    Directory of Open Access Journals (Sweden)

    Chin-Jung Lin

    2012-08-01

    Conclusion: Plate augmentation with retention of the nail with autologous bone grafting may be an effective and reliable alternative in treating nonunion of the femoral shaft fracture after open reduction and internal fixation with intramedullary nail.

  10. 'Femoral head necrosis' in metabolic and hormonal osteopathies

    International Nuclear Information System (INIS)

    Heuck, F.H.W.; Treugut, H.

    1984-01-01

    The pathogenesis of bone necrosis is discussed with special attention and with respect to metabolic, hormonal, and vascular factors. The influence of statics and dynamics of the hip joint bones for the development of aseptic necrosis are discussed. 45 patients with ''idiopathic femoral head necroses'' were observed, including 6 cases of renal osteopathy following renal transplantation and immune suppression therapy, 14 cases of long term corticoid therapy, and 11 cases of liver diseases of different genesis. The femoral head necrosis understood as complication of an osteopathy. In our patients there were 31 males and 14 females - which means higher involvement of males. Plain radiological findings and CT-findings of changes of the femoral heat structure in different stages of the disease are described. Early diagnosis of metabolic and hormonal osteopathies is demanded for a joint keeping therapy of the beginning femoral head necrosis. (orig.) [de

  11. Short-term outcome of patients with closed comminuted femoral ...

    African Journals Online (AJOL)

    Short-term outcome of patients with closed comminuted femoral shaft fracture treated with locking intramedullary sign nail at Muhimbili Orthopaedic Institute in Tanzania. Billy T. Haonga, Felix S. Mrita, Edmundo E. Ndalama, Jackline E. Makupa ...

  12. Delayed appearance of hypaesthesia and paralysis after femoral nerve block

    Directory of Open Access Journals (Sweden)

    Stefan Landgraeber

    2012-03-01

    Full Text Available We report on a female patient who underwent an arthroscopy of the right knee and was given a continuous femoral nerve block catheter. The postoperative course was initially unremarkable, but when postoperative mobilisation was commenced, 18 hours after removal of the catheter, the patient noticed paralysis and hypaesthesia. Examination confirmed the diagnosis of femoral nerve dysfunction. Colour duplex sonography of the femoral artery and computed tomography of the lumbar spine and pelvis yielded no pathological findings. Overnight the neurological deficits decreased without therapy and were finally no longer detectable. We speculate that during the administration of the local anaesthetic a depot formed, localised in the medial femoral intermuscular septa, which was leaked after first mobilisation. To our knowledge no similar case has been published up to now. We conclude that patients who are treated with a nerve block should be informed and physician should be aware that delayed neurological deficits are possible.

  13. Incidence and predictors of post-catheterization femoral artery pseudoaneurysms

    Directory of Open Access Journals (Sweden)

    Hussein Heshmat Kassem

    2013-09-01

    Conclusion: Femoral artery pseudoaneurysms are not uncommon. Female gender, obesity, hypertension, the use of antiplatelet and/or anticoagulant therapy and faulty puncture techniques are independent risk factors for FAPs.

  14. Delayed appearance of hypaesthesia and paralysis after femoral nerve block

    Science.gov (United States)

    Landgraeber, Stefan; Albrecht, Thomas; Reischuck, Ulrich; von Knoch, Marius

    2012-01-01

    We report on a female patient who underwent an arthroscopy of the right knee and was given a continuous femoral nerve block catheter. The postoperative course was initially unremarkable, but when postoperative mobilisation was commenced, 18 hours after removal of the catheter, the patient noticed paralysis and hypaesthesia. Examination confirmed the diagnosis of femoral nerve dysfunction. Colour duplex sonography of the femoral artery and computed tomography of the lumbar spine and pelvis yielded no pathological findings. Overnight the neurological deficits decreased without therapy and were finally no longer detectable. We speculate that during the administration of the local anaesthetic a depot formed, localised in the medial femoral intermuscular septa, which was leaked after first mobilisation. To our knowledge no similar case has been published up to now. We conclude that patients who are treated with a nerve block should be informed and physician should be aware that delayed neurological deficits are possible. PMID:22577509

  15. Femoral neck fractures complicating gaucher disease in children

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, A B; Jacobs, B

    1984-09-01

    In normal children, fractures of the femoral neck are uncommon and accompany severe trauma and multiple injuries elsewhere in the skeleton. In children with Gaucher disease, a rare hereditary disorder of lipid metabolism, midcervical or basicervical fractures can occur with minor or no trauma and without other injury to the skeleton. Three children with Gaucher disease who developed pathologic fractures of the femoral neck are described. In all three, the fractures occurred between five and nine years of age, and the fracture lines passed through areas of abnormal bone characterized by poorly defined patches of increased and decreased density and cortical thinning along the medial femoral necks. In the affected hips, there was no evidence of avascular necrosis of the femoral heads at the time of injury. One child's fracture was preceeded by multiple bone 'crisis' localized to the proximal femora.

  16. Telomere length and depression

    DEFF Research Database (Denmark)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Rode, Line

    2017-01-01

    BACKGROUND: Depression has been cross-sectionally associated with short telomeres as a measure of biological age. However, the direction and nature of the association is currently unclear. AIMS: We examined whether short telomere length is associated with depression cross-sectionally as well...... as prospectively and genetically. METHOD: Telomere length and three polymorphisms, TERT, TERC and OBFC1, were measured in 67 306 individuals aged 20-100 years from the Danish general population and associated with register-based attendance at hospital for depression and purchase of antidepressant medication....... RESULTS: Attendance at hospital for depression was associated with short telomere length cross-sectionally, but not prospectively. Further, purchase of antidepressant medication was not associated with short telomere length cross-sectionally or prospectively. Mean follow-up was 7.6 years (range 0...

  17. Validation of a new classification system for interprosthetic femoral fractures.

    Science.gov (United States)

    Pires, Robinson Esteves Santos; Silveira, Marcelo Peixoto Sena; Resende, Alessandra Regina da Silva; Junior, Egidio Oliveira Santana; Campos, Tulio Vinicius Oliveira; Santos, Leandro Emilio Nascimento; Balbachevsky, Daniel; Andrade, Marco Antônio Percope de

    2017-07-01

    Interprosthetic femoral fracture (IFF) incidence is gradually increasing as the population is progressively ageing. However, treatment remains challenging due to several contributing factors, such as poor bone quality, patient comorbidities, small interprosthetic fragment, and prostheses instability. An effective and specific classification system is essential to optimize treatment management, therefore diminishing complication rates. This study aims to validate a previously described classification system for interprosthetic femoral fractures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Incidence and predictors of post-catheterization femoral artery pseudoaneurysms

    OpenAIRE

    Kassem, Hussein Heshmat; Elmahdy, Mahmoud Farouk; Ewis, Essam Baligh; Mahdy, Soilman Ghareeb

    2013-01-01

    Background: Femoral artery pseudoaneurysm (FAP) is a troublesome complication after transfemoral catheter procedures. The incidence and predictors of FAP as a separate entity have not been extensively studied. Aim: Detect prospectively the incidence and predictors of post catheterization FAP. Methods: From June 2009 till June 2011, we prospectively included all patients who underwent catheterization from the femoral approach. Duplex ultrasound was performed in cases with clinical suspic...

  19. Mechanical Characterization of Femoral Cartilage Under Unicompartimental Osteoarthritis

    OpenAIRE

    Vidal-Lesso, A.; Ledesma-Orozco, E.; Daza-Benítez, L.; Lesso-Arroyo, R.

    2014-01-01

    The aim of this study was to determine the mechanical properties and thickness of articular cartilage in the unaffected femoral regions in cases of unicompartimental osteoarthritis on the knees. The specimens were tested using a 3mm plane-ended cylindrical indenter and a displacement of 0.5mm was applied at specific points in seven femoral knee cartilages with unicompartimental osteoarthritis. The thickness, stiffness, elastic modulus, shear modulus and bulk modulus were obtained. These prope...

  20. Engineers win award for Swiss tunnel

    CERN Multimedia

    2003-01-01

    A Derby engineering consultancy has won the Tunnelling Industry Award 2003 for Excellence in Tunnel Design, offered by the British Tunnelling Society, for its work on the LHC in Geneva, Switzerland (1/2 page).

  1. Thermovoltages in vacuum tunneling investigated by scanning tunneling microscopy

    OpenAIRE

    Hoffmann, D. H.; Rettenberger, Armin; Grand, Jean Yves; Läuger, K.; Leiderer, Paul; Dransfeld, Klaus; Möller, Rolf

    1995-01-01

    By heating the tunneling tip of a scanning tunneling microscope the thermoelectric properties of a variable vacuum barrier have been investigated. The lateral variation of the observed thermovoltage will be discussed for polycrystalline gold, stepped surfaces of silver, as well as for copper islands on silver.

  2. Tunneling time, the Hartman effect, and superluminality: A proposed resolution of an old paradox

    International Nuclear Information System (INIS)

    Winful, Herbert G.

    2006-01-01

    The issue of tunneling time is replete with controversy and paradoxes. The controversy stems from the fact that many tunneling time definitions seem to predict superluminal tunneling velocities. One prediction, termed the Hartman effect, states that the tunneling time becomes independent of barrier length for thick enough barriers, ultimately resulting in unbounded tunneling velocities. Experiments done with 'single photons', classical light waves, and microwaves all show this apparent superluminality. The origin of these paradoxical effects has been a mystery for decades. In this article, we review the history of tunneling times starting with the early work of MacColl, Hartman, and Wigner. We discuss some of the tunneling time definitions, with particular emphasis on the phase time (also known as the group delay or Wigner time) and the dwell time. The key experiments are reviewed. We then discuss our recent work, which suggests that the group delay in tunneling is not a transit time as has been assumed for decades. It is, in reality, a lifetime and hence should not be used to assign a speed of barrier traversal. We show how this new understanding along with the concept of energy storage and release resolves all the outstanding tunneling time paradoxes

  3. Universal tunneling behavior in technologically relevant P/N junction diodes

    International Nuclear Information System (INIS)

    Solomon, Paul M.; Jopling, Jason; Frank, David J.; D'Emic, Chris; Dokumaci, O.; Ronsheim, P.; Haensch, W.E.

    2004-01-01

    Band-to-band tunneling was studied in ion-implanted P/N junction diodes with profiles representative of present and future silicon complementary metal-oxide-silicon (CMOS) field effect transistors. Measurements were done over a wide range of temperatures and implant parameters. Profile parameters were derived from analysis of capacitance versus voltage characteristics, and compared to secondary-ion mass spectroscopy analysis. When the tunneling current was plotted against the effective tunneling distance (tunneling distance corrected for band curvature) a quasi-universal exponential reduction of tunneling current versus, tunneling distance was found with an attenuation length of 0.38 nm, corresponding to a tunneling effective mass of 0.29 times the free electron mass (m 0 ), and an extrapolated tunneling current at zero tunnel distance of 5.3x10 7 A/cm 2 at 300 K. These results are directly applicable for predicting drain to substrate currents in CMOS transistors on bulk silicon, and body currents in CMOS transistors in silicon-on-insulator

  4. Tunnel pressure waves - A smartphone inquiry on rail travel

    Science.gov (United States)

    Müller, Andreas; Hirth, Michael; Kuhn, Jochen

    2016-02-01

    When traveling by rail, you might have experienced the following phenomenon: The train enters a tunnel, and after some seconds a noticeable pressure change occurs, as perceived by your ears or even by a rapid wobbling of the train windows. The basic physics is that pressure waves created by the train travel down the tunnel, are reflected at its other end, and travel back until they meet the train again. Here we will show (i) how this effect can be well understood as a kind of large-scale outdoor case of a textbook paradigm, and (ii) how, e.g., a prediction of the tunnel length from the inside of a moving train on the basis of this model can be validated by means of a mobile phone measurement.

  5. Design Optimization of Liquid Nitrogen Based IQF Tunnel

    Science.gov (United States)

    Datye, A. B.; Narayankhedkar, K. G.; Sharma, G. K.

    2006-04-01

    A design methodology for an Individual Quick Freezing (IQF) tunnel using liquid nitrogen is developed and the design based on this methodology is validated using the data of commercial tunnels. The design takes care of heat gains due to the conveyor belt which is exposed to atmosphere at the infeed and outfeed ends. The design also considers the heat gains through the insulation as well as due to circulating fans located within the tunnel. For minimum liquid nitrogen consumption, the ratio of the length of the belt, L (from infeed to out feed) to the width of the belt, W can be considered as a parameter. The comparison of predicted and reported liquid nitrogen (experimental data) consumption shows good agreement and is within 10 %.

  6. The Bolmen tunnel project - evaluation of geophysical site investigation methods

    International Nuclear Information System (INIS)

    Stanfors, R.

    1987-12-01

    The report presents geophysical measurements along and adjacent to the tunnel and an evaluation of the ability of the various methods to permit prediction of rock mass parameters of significance to stability and water bearing ability. The evaluation shows that, using airborne electro-magnetic surveys, it was possible to indicate about 80% of alla the zones of weakness more than 50 m wide in the tunnel. Airborne magnetic surveys located about 90% of all dolerite dykes more than 10 m wide. Ground-level VLF and Slingram methods of electro-magnetic measurement indicated 75% and 85% respectively of all zones of weakness more than 50 m wide. Resistivity methods were successfully used to locate clay filled and water-bearing fracture zones. About 75% of the length of tunnel over which resistivity values below 500 ohm m were measured required shotcrete support and pre-grouting. (orig./DG)

  7. Suppression of tunneling leakage current in junctionless nanowire transistors

    International Nuclear Information System (INIS)

    Lou, Haijun; Li, Dan; Dong, Yan; Lin, Xinnan; He, Jin; Yang, Shengqi; Chan, Mansun

    2013-01-01

    In this paper, the characteristics of tunneling leakage current for the dual-material gate junctionless nanowire transistor (DMG-JNT) are investigated by three-dimensional numerical simulations and compared with conventional junctionless nanowire transistor (JNT). The suppression of the tunneling leakage current on the JNT by introducing an energy band step with the DMG structure is verified and presented for the first time. The effects of channel length on the DMG-JNT and the JNT are also studied. Results showed that the tunneling leakage current of the DMG-JNT is two orders smaller than that of the JNT, and further, the DMG-JNT exhibits superior scaling capability. Two key design parameters of the DMG-JNT, control gate ratio (Ra) and work function difference (δW), have been optimized and the optimal ranges of Ra and δW are pointed out. (paper)

  8. Suppression of tunneling leakage current in junctionless nanowire transistors

    Science.gov (United States)

    Lou, Haijun; Li, Dan; Dong, Yan; Lin, Xinnan; He, Jin; Yang, Shengqi; Chan, Mansun

    2013-12-01

    In this paper, the characteristics of tunneling leakage current for the dual-material gate junctionless nanowire transistor (DMG-JNT) are investigated by three-dimensional numerical simulations and compared with conventional junctionless nanowire transistor (JNT). The suppression of the tunneling leakage current on the JNT by introducing an energy band step with the DMG structure is verified and presented for the first time. The effects of channel length on the DMG-JNT and the JNT are also studied. Results showed that the tunneling leakage current of the DMG-JNT is two orders smaller than that of the JNT, and further, the DMG-JNT exhibits superior scaling capability. Two key design parameters of the DMG-JNT, control gate ratio (Ra) and work function difference (δW), have been optimized and the optimal ranges of Ra and δW are pointed out.

  9. OUTCOME OF INTERTROCHANTERIC FRACTURES TREATED WITH SHORT FEMORAL NAIL

    Directory of Open Access Journals (Sweden)

    Yadkikar Shriniwas V, Yadkikar Vishnu S, Patel Mayank, Dhruvilkumar Gandhi, Kunkulol Rahul

    2015-07-01

    Full Text Available Aim: To study the functional and anatomical outcome of Inter trochanteric fractures of femur treated with Short femoral nail. Method: This was retrospective study carried out in which 60 patients (50 Male & 10 Female of 5th to 8th decade of life who underwent Short femoral nail fixation for both Stable & unstable Inter Trochanteric fractures. From the records each patient data was assessed for time required for mobilization, average fracture healing time, degree and grade of hip range of movements, complications, anatomical reduction achieved using Short femoral nail fixation. Results: 55 cases achieved Anatomical reduction. Good to Excellent Hip range of Motion was in 55 (90 % cases. Fracture union was seen in all cases. No evidence of Z Effect, AVN of femoral head, Implant failure, Fracture of femoral shaft below the Nail tip was seen in any case, However Reverse Z Effect was seen in 4 & shortening of less than 2 cm was seen in 2 cases, External rotation of 10 degree was seen in1 case. Average fracture Union time was 14 weeks. Conclusion: Short femoral nail appears to be better implant for fixation of both Stable & unstable Inter Trochanteric fractures as it fulfills the biomechanical demands being minimally invasive, less blood loss , it prevents excessive varus collapse at fracture site, produces less stress riser effect below the nail tip, Short operative time, Facilitates early mobilization & functional recovery of patients. But Anatomical fracture reduction & optimal implant placement are absolutely must for better results.

  10. Femoral Neck Shaft Angle in Men with Fragility Fractures

    Directory of Open Access Journals (Sweden)

    S. P. Tuck

    2011-01-01

    Full Text Available Introduction. Femoral neck shaft angle (NSA has been reported to be an independent predictor of hip fracture risk in men. We aimed to assess the role of NSA in UK men. Methods. The NSA was measured manually from the DXA scan printout in men with hip (62, 31 femoral neck and 31 trochanteric, symptomatic vertebral (91, and distal forearm (67 fractures and 389 age-matched control subjects. Age, height, weight, and BMD (g/cm2: lumbar spine, femoral neck, and total femur measurements were performed. Results. There was no significant difference in mean NSA between men with femoral neck and trochanteric hip fractures, so all further analyses of hip fractures utilised the combined data. There was no difference in NSA between those with hip fractures and those without (either using the combined data or analysing trochanteric and femoral neck shaft fractures separately, nor between fracture subjects as a whole and controls. Mean NSA was smaller in those with vertebral fractures (129.2° versus 131°: P=0.001, but larger in those with distal forearm fractures (129.8° versus 128.5°: P=0.01. Conclusions. The conflicting results suggest that femoral NSA is not an important determinant of hip fracture risk in UK men.

  11. Magnetic tunnel junctions with monolayer hexagonal boron nitride tunnel barriers

    Energy Technology Data Exchange (ETDEWEB)

    Piquemal-Banci, M.; Galceran, R.; Bouzehouane, K.; Anane, A.; Petroff, F.; Fert, A.; Dlubak, B.; Seneor, P. [Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767 (France); Caneva, S.; Martin, M.-B.; Weatherup, R. S.; Kidambi, P. R.; Robertson, J.; Hofmann, S. [Department of Engineering, University of Cambridge, Cambridge CB21PZ (United Kingdom); Xavier, S. [Thales Research and Technology, 1 avenue Augustin Fresnel, Palaiseau 91767 (France)

    2016-03-07

    We report on the integration of atomically thin 2D insulating hexagonal boron nitride (h-BN) tunnel barriers into Co/h-BN/Fe magnetic tunnel junctions (MTJs). The h-BN monolayer is directly grown by chemical vapor deposition on Fe. The Conductive Tip Atomic Force Microscopy (CT-AFM) measurements reveal the homogeneity of the tunnel behavior of our h-BN layers. As expected for tunneling, the resistance depends exponentially on the number of h-BN layers. The h-BN monolayer properties are also characterized through integration into complete MTJ devices. A Tunnel Magnetoresistance of up to 6% is observed for a MTJ based on a single atomically thin h-BN layer.

  12. Necrosis de la cabeza femoral tras fractura del cuello femoral tratada mediante osteosíntesis

    OpenAIRE

    Martínez Martín, Angel Antonio; Panisello Sebastiá, Juan José; Lallana Duplá, J.; Herrera Rodríguez, Antonio

    2000-01-01

    Se presenta un análisis retrospectivo de las necrosis aparecidas en 233 pacientes con fractura de cuello femoral fijada con tornillos de esponjosa. La edad media fue de 80,6 años. Setenta y un pacientes (26%) tuvieron una fractura no desplazada (Garden I o II) y 172 (74%) una fractura desplazada (Garden III o IV). Seis meses tras la cirugía 170 pacientes sobrevivían (72,9%). Treinta y cuatro de ellos (20%) habían desarrollado necrosis y 10 (5,9%) colapso. Tras un seguimiento de 12 meses 114 p...

  13. Impact of carbon nanotube length on electron transport in aligned carbon nanotube networks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeonyoon; Stein, Itai Y. [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Devoe, Mackenzie E. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Lewis, Diana J.; Lachman, Noa; Buschhorn, Samuel T.; Wardle, Brian L., E-mail: wardle@mit.edu [Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Kessler, Seth S. [Metis Design Corporation, 205 Portland St., Boston, Massachusetts 02114 (United States)

    2015-02-02

    Here, we quantify the electron transport properties of aligned carbon nanotube (CNT) networks as a function of the CNT length, where the electrical conductivities may be tuned by up to 10× with anisotropies exceeding 40%. Testing at elevated temperatures demonstrates that the aligned CNT networks have a negative temperature coefficient of resistance, and application of the fluctuation induced tunneling model leads to an activation energy of ≈14 meV for electron tunneling at the CNT-CNT junctions. Since the tunneling activation energy is shown to be independent of both CNT length and orientation, the variation in electron transport is attributed to the number of CNT-CNT junctions an electron must tunnel through during its percolated path, which is proportional to the morphology of the aligned CNT network.

  14. Impact of carbon nanotube length on electron transport in aligned carbon nanotube networks

    International Nuclear Information System (INIS)

    Lee, Jeonyoon; Stein, Itai Y.; Devoe, Mackenzie E.; Lewis, Diana J.; Lachman, Noa; Buschhorn, Samuel T.; Wardle, Brian L.; Kessler, Seth S.

    2015-01-01

    Here, we quantify the electron transport properties of aligned carbon nanotube (CNT) networks as a function of the CNT length, where the electrical conductivities may be tuned by up to 10× with anisotropies exceeding 40%. Testing at elevated temperatures demonstrates that the aligned CNT networks have a negative temperature coefficient of resistance, and application of the fluctuation induced tunneling model leads to an activation energy of ≈14 meV for electron tunneling at the CNT-CNT junctions. Since the tunneling activation energy is shown to be independent of both CNT length and orientation, the variation in electron transport is attributed to the number of CNT-CNT junctions an electron must tunnel through during its percolated path, which is proportional to the morphology of the aligned CNT network

  15. On the flow of groundwater in closed tunnels. Generic hydrogeological modelling of nuclear waste repository, SFL 3-5

    International Nuclear Information System (INIS)

    Holmen, J.G.

    1997-06-01

    The purpose is to study the flow of groundwater in closed tunnels by use of mathematical models. The calculations were based on three dimensional models, presuming steady state conditions. The stochastic continuum approach was used for representation of a heterogeneous rock mass. The size of the calculated flow is given as a multiple of an unknown regional groundwater flow. The size of the flow in a tunnel has been studied, as regards: Direction of the regional groundwater flow, Tunnel length, width and conductivity; Heterogeneity of the surrounding rock mass; Flow barriers and encapsulation inside a tunnel. The study includes a model of the planned repository for nuclear waste (SFL 3-5). The flow through the tunnels is estimated for different scenarios. The stochastic continuum approach has been investigated, as regards the representation of a scale dependent heterogeneous conductivity. An analytical method is proposed for the scaling of measured conductivity values, the method is consistent with the stochastic continuum approach. Some general conclusions from the work are: The larger the amount of heterogeneity, the larger the expected flow; The effects of the heterogeneity will decrease with increased tunnel length; If the conductivity of the tunnel is smaller than a threshold value, the tunnel conductivity is the most important parameter; If the tunnel conductivity is large and the tunnel is long, the most important parameter is the direction of the regional flow; Given a heterogeneous rock mass, if the tunnel length is shorter than about 500 m, the heterogeneity will be an important parameter, for lengths shorter than about 250 m, probably the most important; The flow through an encapsulation surrounded by a flow barrier is mainly dependent on the conductivity of the barrier. 70 refs, 110 figs, 10 tabs

  16. On the flow of groundwater in closed tunnels. Generic hydrogeological modelling of nuclear waste repository, SFL 3-5

    Energy Technology Data Exchange (ETDEWEB)

    Holmen, J.G. [Uppsala Univ. (Sweden). Inst. of Earth Sciences]|[Golder Associates AB (Sweden)

    1997-06-01

    The purpose is to study the flow of groundwater in closed tunnels by use of mathematical models. The calculations were based on three dimensional models, presuming steady state conditions. The stochastic continuum approach was used for representation of a heterogeneous rock mass. The size of the calculated flow is given as a multiple of an unknown regional groundwater flow. The size of the flow in a tunnel has been studied, as regards: Direction of the regional groundwater flow, Tunnel length, width and conductivity; Heterogeneity of the surrounding rock mass; Flow barriers and encapsulation inside a tunnel. The study includes a model of the planned repository for nuclear waste (SFL 3-5). The flow through the tunnels is estimated for different scenarios. The stochastic continuum approach has been investigated, as regards the representation of a scale dependent heterogeneous conductivity. An analytical method is proposed for the scaling of measured conductivity values, the method is consistent with the stochastic continuum approach. Some general conclusions from the work are: The larger the amount of heterogeneity, the larger the expected flow; The effects of the heterogeneity will decrease with increased tunnel length; If the conductivity of the tunnel is smaller than a threshold value, the tunnel conductivity is the most important parameter; If the tunnel conductivity is large and the tunnel is long, the most important parameter is the direction of the regional flow; Given a heterogeneous rock mass, if the tunnel length is shorter than about 500 m, the heterogeneity will be an important parameter, for lengths shorter than about 250 m, probably the most important; The flow through an encapsulation surrounded by a flow barrier is mainly dependent on the conductivity of the barrier. 70 refs, 110 figs, 10 tabs.

  17. Nonunion of the femoral neck: Possibilities and limitations of the various treatment modalities

    Directory of Open Access Journals (Sweden)

    Raaymakers Ernst

    2008-01-01

    Full Text Available Nowadays in cases of nonunions of the femoral neck, the surgeon is tempted to perform prosthetic replacement of the hip, more so if there is also evidence of avascular necrosis of the head of femur. This provides rapid pain relief and allows early mobilization. However, long-term results of hip arthroplasties, especially in younger people and in the presence of osteopenia, are not always as expected; and a less radical approach is worth considering. The intertrochanteric valgization osteotomy, described by Pauwels, is an excellent alternative for healthy patients up to 65 years of age with a nonunion of the femoral neck. A union rate of 80-90% of the nonunion is described by most authors. Leg length inequallity, rotational and angular deformities can be corrected at the same time. During the period 1973-1995, we performed valgization osteotomy according to Pauwels in 66 patients of, 18-72 years old (mean 49.5 years. 24 (37% of our patients died 4 months to 24 years (mean: 9.5 years after the operation. Union of the femoral neck was achieved in 58 (88% of the 66 patients; union of the osteotomy in 65 patients (99%. A good or excellent result was achieved in 62% (23 uneventful and 13 with healed, necrosis/arthrosis without need for further treatment of our patients. However, the method has its limits. We feel if there is too little bone stock inside the femoral head, a valgization osteotomy does not give good result. The radiographic signs of avascular necrosis in patients over 30 years of age is considered a contraindication for an osteotomy. However our results show that it is worthwhile trying to save the joint of young patients even in case of a segmental collapse. In the race between revascularization and collapse, often revascularization is the winner. We deliberately give nature its chance and don′t rely on the result of bleeding from drill holes in the head, nuclear scans and other methods to estimate vascularity. A secondary total hip

  18. Combined Radial and Femoral Access Strategy and Radial-Femoral Rendezvous in Patients With Long and Complex Iliac Occlusions.

    Science.gov (United States)

    Hanna, Elias B; Mogabgab, Owen N; Baydoun, Hassan

    2018-01-01

    We present cases of complex, calcified iliac occlusive disease revascularized via a combined radial-femoral access strategy. Through a 6-French, 125-cm transradial guiding catheter, antegrade guidewires and catheters are advanced into the iliac occlusion, while retrograde devices are advanced transfemorally. The transradial and transfemoral channels communicate, allowing the devices to cross the occlusion into the true lumen (radial-femoral antegrade-retrograde rendezvous).

  19. Estimated carotid-femoral pulse wave velocity has similar predictive value as measured carotid-femoral pulse wave velocity

    DEFF Research Database (Denmark)

    Greve, Sara V; Blicher, Marie K; Kruger, Ruan

    2016-01-01

    BACKGROUND: Carotid-femoral pulse wave velocity (cfPWV) adds significantly to traditional cardiovascular risk prediction, but is not widely available. Therefore, it would be helpful if cfPWV could be replaced by an estimated carotid-femoral pulse wave velocity (ePWV) using age and mean blood pres...... that these traditional risk scores have underestimated the complicated impact of age and blood pressure on arterial stiffness and cardiovascular risk....

  20. Randomized Trial of the SMART Stent versus Balloon Angioplasty in Long Superficial Femoral Artery Lesions: The SUPER Study

    International Nuclear Information System (INIS)

    Chalmers, Nicholas; Walker, Paul T.; Belli, Anna-Maria; Thorpe, Anthony P.; Sidhu, Paul S.; Robinson, Graham; Ransbeeck, Mariella van; Fearn, Steven A.

    2013-01-01

    To determine whether primary stenting reduces the rate of restenosis compared with balloon angioplasty alone in the endovascular treatment of long superficial femoral artery lesions; and to assess the effect of treatment on quality of life. A total of 150 patients with superior femoral artery occlusion or severe stenosis of 5–22 cm length from 17 UK centers were randomized to either primary stenting with the SMART stent or balloon angioplasty (i.e., percutaneous transluminal angioplasty, PTA). Bailout stent placement was permitted in case of inadequate result from PTA. The primary end point was restenosis measured by duplex ultrasound at 1 year. Quality-of-life assessments were performed by the EuroQol (EQ)-5D questionnaire. Mean lesion length was 123.0 mm in the stent group and 116.8 mm in the PTA group. A total of 140 (93.3 %) of 150 had total occlusions. At 12 months’ follow-up, restenosis measured by Duplex ultrasound was not significantly different between the stent and PTA groups by intention-to-treat or as-treated analyses: 47.2 versus 43.5 % (p = 0.84) and 40.8 versus 46.7 % (p = 0.68), respectively. There were fewer target lesion revascularizations in patients randomized to stenting, but this did not reach statistical significance (12.5 vs. 20.8 %, p = 0.26). There was no difference in the rate of amputation. Patients in both groups reported improved quality of life. Primary stenting of long lesions in predominantly occluded superficial femoral arteries does not reduce the rate of binary restenosis compared with balloon angioplasty and bailout stenting. Both treatment strategies conferred a meaningful and sustained improvement to the quality of life of patients with severe superficial femoral artery disease.

  1. Spin tunnelling in mesoscopic systems

    Indian Academy of Sciences (India)

    We study spin tunnelling in molecular magnets as an instance of a mesoscopic phenomenon, with special emphasis on the molecule Fe8. We show that the tunnel splitting between various pairs of Zeeman levels in this molecule oscillates as a function of applied magnetic field, vanishing completely at special points in the ...

  2. Hawking temperature from tunnelling formalism

    OpenAIRE

    Mitra, P.

    2007-01-01

    It has recently been suggested that the attempt to understand Hawking radiation as tunnelling across black hole horizons produces a Hawking temperature double the standard value. It is explained here how one can obtain the standard value in the same tunnelling approach.

  3. Relationship between Widening and Position of the Tunnels and Clinical Results of Anterior Cruciate Ligament Reconstruction to Knee Osteoarthritis: 30 Patients at a Minimum Follow-Up of 10 Years.

    Science.gov (United States)

    Ayala-Mejias, Juan Diego; Garcia-Gonzalez, Benjamin; Alcocer-Perez-España, Luis; Villafañe, Jorge Hugo; Berjano, Pedro

    2017-07-01

    To evaluate the relationship between tunnel position and widening and long-term clinical results in anterior cruciate ligament (ACL) reconstruction, a retrospective cohort of 30 patients undergoing ACL reconstruction with double semitendinous plus double gracilis (SAC technique) with longer than 10-year follow-up was selected. CT scans in the first 3 months and at final follow-up was evaluated. Position, angle, and widening of tunnels including Nebelung criteria were recorded in all CT scans. Physical, KT-1000, and clinical evaluation were performed at final follow-up. Outcomes and knee arthritis severity were evaluated at final follow-up. Mean follow-up was 11.2 ± 1.2. At final follow-up, 85 and 57% of tibial and femoral tunnels, respectively, developed some degree of enlargement. Frontal tibial angle (mean) was 72°, sagittal tibial angle 63°, frontal femoral angle 47°, sagittal femoral angle 20°, and tunnels divergence angle 36°. Preoperatively, KT-1000 30L and Lachman test scores were 5.52 and 5.79 respectively. In the last follow-up, 30L and manual Lachman test scores were 0.97 and 1.13, respectively ( p  verticalization. Tibial tunnel dilation was associated with long-term degenerative changes but not with final knee instability. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Femoral neck-shaft angle in extra-capsular proximal femoral fracture fixation; does it make a TAD of difference?

    Science.gov (United States)

    Walton, N P; Wynn-Jones, H; Ward, M S; Wimhurst, J A

    2005-11-01

    The effect of femoral neck-shaft angle and implant type on the accuracy of lag screw placement in extra-capsular proximal femoral fracture fixation was investigated. Radiographs of all extra-capsular proximal femoral fractures seen in one unit over 18 months were reviewed. Of 399 cases, 307 (237 female, 70 male) were included in the study as they had no contra-lateral proximal femoral metal work. Femoral neck-shaft angle (NSA) of the uninjured hip and magnification adjusted tip-apex distance (TAD) of femoral head lag screw were measured. Type of fixation implant was 135 degrees classic hip screw (CHS) (n=144) or 130 degrees intra-medullary hip screw (IMHS) (n=163). Mean contra-lateral NSA was 130.2 degrees (112.9--148 degrees ) and 64 patients (58 female, 6 male) had a NSA TAD was 18.7 mm (5.8--43.8mm) and 88.9% of cases had a TAD of less than 25 mm. TAD values were significantly greater using an IMHS if NSA was 125 degrees (p=0.028). This was not the case with the CHS. The use of the 130 degrees -IMHS in patients with a NSA 125 degrees and caution is advocated when using this device in such cases.

  5. Tunneling Ionization of Diatomic Molecules

    DEFF Research Database (Denmark)

    Svensmark, Jens Søren Sieg

    2016-01-01

    When a molecule is subject to a strong laser field, there is a probability that an electron can escape, even though the electrons are bound by a large potential barrier. This is possible because electrons are quantum mechanical in nature, and they are therefore able to tunnel through potential...... barriers, an ability classical particles do not possess. Tunnelling is a fundamental quantum mechanical process, a process that is distinctly non-classical, so solving this tunnelling problem is not only relevant for molecular physics, but also for quantum theory in general. In this dissertation the theory...... of tunneling ionizaion of molecules is presented and the results of numerical calculations are shown. One perhaps surprising result is, that the frequently used Born-Oppenheimer approximation breaks down for weak fields when describing tunneling ionization. An analytic theory applicable in the weak-field limit...

  6. Tunneling from the past horizon

    Science.gov (United States)

    Kang, Subeom; Yeom, Dong-han

    2018-04-01

    We investigate a tunneling and emission process of a thin-shell from a Schwarzschild black hole, where the shell was initially located beyond the Einstein-Rosen bridge and finally appears at the right side of the Penrose diagram. In order to obtain such a solution, we should assume that the areal radius of the black hole horizon increases after the tunneling. Hence, there is a parameter range such that the tunneling rate is exponentially enhanced, rather than suppressed. We may have two interpretations regarding this. First, such a tunneling process from the past horizon is improbable by physical reasons; second, such a tunneling is possible in principle, but in order to obtain a stable Einstein-Rosen bridge, one needs to restrict the parameter spaces. If such a process is allowed, this can be a nonperturbative contribution to Einstein-Rosen bridges as well as eternal black holes.

  7. Analysis of Co-Tunneling Current in Fullerene Single-Electron Transistor

    Science.gov (United States)

    KhademHosseini, Vahideh; Dideban, Daryoosh; Ahmadi, MohammadTaghi; Ismail, Razali

    2018-05-01

    Single-electron transistors (SETs) are nano devices which can be used in low-power electronic systems. They operate based on coulomb blockade effect. This phenomenon controls single-electron tunneling and it switches the current in SET. On the other hand, co-tunneling process increases leakage current, so it reduces main current and reliability of SET. Due to co-tunneling phenomenon, main characteristics of fullerene SET with multiple islands are modelled in this research. Its performance is compared with silicon SET and consequently, research result reports that fullerene SET has lower leakage current and higher reliability than silicon counterpart. Based on the presented model, lower co-tunneling current is achieved by selection of fullerene as SET island material which leads to smaller value of the leakage current. Moreover, island length and the number of islands can affect on co-tunneling and then they tune the current flow in SET.

  8. Small-scale tunnel test for blast performance

    International Nuclear Information System (INIS)

    Felts, J E; Lee, R J

    2014-01-01

    The data reported here provide a validation of a small-scale tunnel test as a tool to guide the optimization of new explosives for blast performance in tunnels. The small-scale arrangement consisted of a 2-g booster and 10-g sample mounted at the closed end of a 127 mm diameter by 4.6-m long steel tube with pressure transducers along its length. The three performance characteristics considered were peak pressure, initial energy release, and impulse. The relative performance from five explosives was compared to that from a 1.16-m diameter by 30-m long tunnel that used 2.27-kg samples. The peak pressure values didn't correlate between the tunnels. Partial impulse for the explosives did rank similarly. The initial energy release was determined from a one-dimensional point-source analysis, which nearly tracked with impulse suggesting additional energy released further down the tunnel for some explosives. This test is a viable tool for optimizing compositional variations for blast performance in target scenarios of similar geometry.

  9. Extended fuel cycle length

    International Nuclear Information System (INIS)

    Bruyere, M.; Vallee, A.; Collette, C.

    1986-09-01

    Extended fuel cycle length and burnup are currently offered by Framatome and Fragema in order to satisfy the needs of the utilities in terms of fuel cycle cost and of overall systems cost optimization. We intend to point out the consequences of an increased fuel cycle length and burnup on reactor safety, in order to determine whether the bounding safety analyses presented in the Safety Analysis Report are applicable and to evaluate the effect on plant licensing. This paper presents the results of this examination. The first part indicates the consequences of increased fuel cycle length and burnup on the nuclear data used in the bounding accident analyses. In the second part of this paper, the required safety reanalyses are presented and the impact on the safety margins of different fuel management strategies is examined. In addition, systems modifications which can be required are indicated

  10. Short uncemented stems allow greater femoral flexibility and may reduce peri-prosthetic fracture risk: a dry bone and cadaveric study.

    Science.gov (United States)

    Jones, Christopher; Aqil, Adeel; Clarke, Susannah; Cobb, Justin P

    2015-09-01

    Short femoral stems for uncemented total hip arthroplasty have been introduced as a safe alternative to traditional longer stem designs. However, there has been little biomechanical examination of the effects of stem length on complications of surgery. This study aims to examine the effect of femoral stem length on torsional resistance to peri-prosthetic fracture. We tested 16 synthetic and two paired cadaveric femora. Specimens were implanted and then rapidly rotated until fracture to simulate internal rotation on a planted foot, as might occur during stumbling. 3D planning software and custom-printed 3D cutting guides were used to enhance the accuracy and consistency of our stem insertion technique. Synthetic femora implanted with short stems fractured at a significantly higher torque (27.1 vs. 24.2 Nm, p = 0.03) and angle (30.3° vs. 22.3°, p = 0.002) than those implanted with long stems. Fracture patterns of the two groups were different, but showed remarkable consistency within each group. These characteristic fracture patterns were closely replicated in the pair of cadaveric femora. This new short-stemmed press-fit femoral component allows more femoral flexibility and confers a higher resistance to peri-prosthetic fracture from torsional forces than long stems.

  11. Prevention of excessive postoperative sliding of the short femoral nail in femoral trochanteric fractures.

    Science.gov (United States)

    Ito, Juji; Takakubo, Yuya; Sasaki, Kan; Sasaki, Junya; Owashi, Kazuya; Takagi, Michiaki

    2015-05-01

    Lag screw cut-out is one of the major postoperative complications on femoral trochanteric fractures. However, precise analyses of excessive sliding and lag screw cut-out were limited. The purpose of this study was to investigate the factors that induce this unfavorable event. From April 2010 to April 2013, 226 patients were operated in our institute using a short femoral nail. Among them, 177 patients (29 males and 148 females) with a mean age of 84 years (60-97 years), who were followed up >3 months, were included in this study. The postoperative sliding distance, fracture type (AO/OTA classification), tip-apex distance (TAD), reduction pattern in the postoperative X-ray (antero-posterior and lateral views), bone quality (canal flare and cortical indices), walking ability at the time of pre-injury and final follow-up, and complications were investigated retrospectively. The mean sliding distance was 3.7 mm, and one cut-out case (0.6 %) was observed. The sliding distance of the AO/OTA 31-A2 fractures was significantly longer than that of the A1 fractures (p fractures, an accurate reduction in the lateral view at surgery is important, particularly in unstable fractures.

  12. Multiplanar CT assessment of femoral head displacement in slipped capital femoral epiphysis

    Energy Technology Data Exchange (ETDEWEB)

    Monazzam, Shafagh [Rady Children' s Hospital and Health Center, Department of Orthopedics, San Diego, CA (United States); Dwek, Jerry R. [Rady Children' s Hospital and Health Center, Department of Radiology, San Diego, CA (United States); Hosalkar, Harish S. [Center for Hip Preservation, Department of Orthopedic Surgery, TriCity Medical Center, Oceanside, CA (United States)

    2013-12-15

    With recent changing approaches to the management of slipped capital femoral epiphysis (SCFE), the accurate radiographic assessment of maximum extent of displacement is crucial for planning surgical treatment. To determine what plane best represents the maximum SCFE displacement as quantified by the head-neck angle difference (HNAD), whether HNAD can quantitatively differentiate the SCFE cohort from the normal cohort, based on CT, and how Southwick slip angle (SSA) compares to HNAD. We reviewed 19 children with SCFE (23 affected hips) with preoperative CT scans and 27 age- and sex-matched children undergoing abdominal CT for non-orthopedic problems. Head-neck angle (HNA), the angle between the femoral epiphysis and the neck axis, was measured in three planes on each hip and the HNAD (affected - unaffected hip) was determined. SSA was measured on radiographs. The coronal HNAD (mean 8.7 ) was less than both the axial-oblique (mean 30.7 ) and sagittal (mean 37.4 ) HNADs, which were also greater than the HNADs of the normal cohort. Grouping HNAD measurements by SSA severity classification did not consistently distinguish between SCFE severity levels. Axial-oblique and sagittal planes best represent the maximum SCFE displacement while biplanar radiograph may underestimate the extent of the displacement, thereby potentially altering the management between in situ pinning and capital realignment. (orig.)

  13. Effectiveness of Minimally Invasive Plate Osteosynthesis (MIPO on Comminuted Tibial or Femoral Fractures

    Directory of Open Access Journals (Sweden)

    Ali Andalib

    2017-09-01

    Full Text Available Background: Comminuted fractures happen frequently due to traumas. Fixation without opening the fracture site,known as minimally invasive plate osteosynthesis (MIPO, has recently become prevalent. This study has beendesigned to assess the outcomes of this treatment for tibial and femoral comminuted fractures.Methods: A total of 60 patients with comminuted femoral or tibial fractures were operated with MIPO method in thiscross-sectional study at Alzahra university hospital in 2015. Eleven patients were excluded due to lack of adequatefollow-ups. Patients’data including union time; infection in the fractured site; hip and knee range of motion; and anymalunion or deformities like limb length discrepancy were collected after the surgery in every session.Results: Among 32 femoral and 17 tibial fractures, union was completed in48 patients, while only one patient withfemoral fracture had nonunion. The mean union time was 18.57±2.42 weeks. Femur fractures healed faster than tibia(17.76±2.36 compared to 19±2.37 weeks, respectively, P=0.09. None of the patients suffered from infections or fistula.The range of motion in hip and knee remained intact in approximately all patients. Malunion happened in 3 patients; 100internal rotation in 1 patient; and 1cm limb shortening in 2 patients.Conclusion: According to the result of this study, MIPO is a simple and effective method of fixation with a high rateof union as well as minimal complications for comminuted fractures of long bones. Infection is rare, and malunion orany deformity is infrequent. MIPO appears to be a promising and safe treatment alternative for comminuted fractures.

  14. Factors influencing period from surgery to discharge in patients with femoral trochanteric fractures

    Science.gov (United States)

    Shinoda, Soichiro; Mutsuzaki, Hirotaka; Watanabe, Arata; Morita, Hidetaka; Kamioka, Yumiko

    2017-01-01

    [Purpose] The purpose of this study was to investigate factors influencing the period from surgery to discharge in patients with femoral trochanteric fractures. [Subjects and Methods] Sixty patients with femoral trochanteric fractures were investigated retrospectively. Based on the mean period from surgery to discharge (85.6 ± 26.6 days), the patients were divided into two groups: an under-85-day group (range, 29–78 days) and an over-85-day group (87–128 days). Age, gender, fracture type, presence of lesser trochanteric displacement, discharge destination, and walking ability were investigated. The relationship between these factors and the period from surgery to discharge was analyzed with logistic regression analysis. [Results] Age and lesser trochanteric displacement were significantly higher in the over-85-day group, and walking ability before fracture and at discharge were significantly lower in the over-85-day group. Logistic regression analysis showed that lesser trochanteric displacement and age were predictors of the length from surgery to discharge. Lesser trochanteric displacement were observed in 87.5% of these. Immediate displacement after surgery occurred in 57.8% of lesser trochanteric fractures, while 26.3% displaced 1 to 3 weeks after surgery. [Conclusion] This study revealed that lesser trochanteric displacement, higher age, and lower walking ability before fracture and at discharge were associated with longer hospitalizations in patients with femoral trochanteric fractures. Lesser trochanteric displacement were observed in 87.5% of lesser trochanteric fractures. These displacements occurred within 3 weeks after surgery in 84.1% of cases. PMID:29200639

  15. Relativistic distances, sizes, lengths

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1992-01-01

    Such notion as light or retarded distance, field size, formation way, visible size of a body, relativistic or radar length and wave length of light from a moving atom are considered. The relation between these notions is cleared up, their classification is given. It is stressed that the formation way is defined by the field size of a moving particle. In the case of the electromagnetic field, longitudinal sizes increase proportionally γ 2 with growing charge velocity (γ is the Lorentz-factor). 18 refs

  16. Varus femoral osteotomy improves sphericity of the femoral head in older children with severe form of Legg-Calvé-Perthes disease.

    Science.gov (United States)

    Terjesen, Terje; Wiig, Ola; Svenningsen, Svein

    2012-09-01

    In the Norwegian prospective study on Legg-Calvé-Perthes disease (LCPD), we found varus femoral osteotomy gave better femoral head sphericity at a mean of 5 years postoperative than physiotherapy in children older than 6.0 years at diagnosis with femoral head necrosis of more than 50%. That study did not include separate analyses for hips with 100% necrosis and those with a percentage of necrosis between 50% and 100%. We asked whether (1) femoral osteotomy improves femoral head sphericity at followup in all patients with more than 50% femoral head necrosis or in selected groups only and (2) there is a critical age between 6.0 and 10.0 years over which femoral osteotomy does not improve the prognosis. We treated 70 patients with unilateral LCPD, age at diagnosis of more than 6.0 years, and femoral head necrosis of more than 50% with varus femoral osteotomy between 1996 and 2000. We classified necrosis using the Catterall classification. We established a control group of 51 similar children who received physiotherapy. At the 5-year followup visit, the hips were graded according to femoral head shape: spherical, ovoid, or flat. At 5-year followup, there was no difference between the treatment groups in radiographic outcome in Catterall Group 3 hips. In Catterall Group 4 hips, femoral head sphericity was better in the osteotomy group, with flat femoral heads in 14% compared to 75% after physiotherapy. The same trend toward better head sphericity occurred when the lateral pillar classification was used. In children aged 6.0 to 10.0 years, in whom the whole femoral head is affected, femoral head sphericity 5 years after femoral osteotomy was better than that after physiotherapy.

  17. [Femoral artery pseudoaneurysms encountered in orthopedics and traumatology].

    Science.gov (United States)

    Raherinantenaina, F; Rajaonanahary, T M A; Rakoto Ratsimba, H N

    2015-12-01

    Most published articles regarding orthopedic- and trauma-related femoral artery pseudoaneurysms (FAPs) are case reports in English. Reported cases are often associated with a literature review but actually provide little robust data. We wanted to summarize the current knowledge on diagnostic and therapeutic features of these FAPs. A new case of superficial FAP is described followed by a review of the literature. A bibliographic search was performed online (PubMed, ScinceDirect) from 1964 to 2015 using the descriptors "traumatic femoral pseudoaneurysm, orthopedic surgery, osteochondroma". A total of 64 cases of FAPs was analyzed. There were 50 men with an average age of 40.72±26.45 years old. The most common clinical presentation was painful swelling (34%). Arteriography was the commonest radiological investigation used (63%). The main etiologies were orthopedic injuries (47%), surgery of the upper thigh (30%) and femoral osteochondromas (23%). Arterial injuries included superficial femoral (47%) and profunda femoris artery (50%). The treatment was open surgery (56%) or endovascular repair (36%). Deep femoral artery and its branches were embolized (47%) or ligated (38%). Endovascular stenting was performed in 30% of posttraumatic FAPs. All FAPs relating to osteochondromas were repaired surgically. Postoperative courses were uneventful in 95% of patients. Endovascular embolization is preferred in management of postsurgical FAPs which have usually involved the deep femoral artery. Endovascular stenting graft may be proposed for posttraumatic FAPs, for which the superficial femoral trunk is the most often involved vessel. Surgical repair should be performed when endovascular stenting graft is not feasible. Surgical repair is mandatory for all FAPs secondary to traumatic exostoses. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  18. Efficacy Evaluation for the Treatment of Subcapital Femoral Neck Fracture in Young Adults by Capsulotomy Reduction and Closed Reduction

    Directory of Open Access Journals (Sweden)

    Cong Liu

    2015-01-01

    Full Text Available Background: Subcapital femoral neck fracture in young adults has many complications, and the incidence is increasing year-by-year. The selection of the proper operation method to avoid them is an ambiguous matter. This study aimed to evaluate the treatment effect of subcapital femoral neck fracture by the capsulotomy and internal fixation with iliac bone grafting or closed reduction and internal fixation in young adults. Methods: From March 2003 to February 2010, 65 young patients with subcapital femoral neck fractures were treated, including 39 males and 26 females with average age of 34.5 years (range, 19-50 years; 29 cases of the left side and 36 cases of the right side. They were randomly divided into Group A with 34 cases treated by closed reduction and internal fixation and Group B with 31 cases treated by the capsulotomy and internal fixation with iliac bone grafting. The two groups had no significant differences in sex, age, body mass index and preoperative Harris Hip Score. The observation criteria involved the length of the incision, blood loss, operation time, nonunion rate, avascular necrosis of the femoral head (ANFH rate and Harris Hip Score. Results: Four of 65 patients were lost follow-up, and the follow-up rate was 93.8%, the average follow-up time was 38.7 months (range, 33-47 months. In Group A, the incision length was 5.1 ± 2.2 cm, blood loss was 84.0 ± 13.2 ml, and operation time was 52.9 ± 10.2 min. In Group B, the incision length was 15.4 ± 4.6 cm, blood loss was 396.0 ± 21.3 ml, and operation time was 116.5 ± 15.3 min. Nonunion occurred in 8 patients (25.2% in Group A and 1 patient (3.3% in Group B. ANFH occurred in 9 patients (29.1% in Group A and 2 patients (6.7% in Group B. Postoperative Harris Hip Score was 89.0 ± 5.6 in Group A and 95.0 ± 4.5 in Group B. The above index of two groups was considered statistically significant (P < 0.05. Conclusions: Capsulotomy and internal fixation with iliac bone grafting can

  19. Fluctuation Dominated Josephson Tunneling with a Scanning Tunneling Microscope

    International Nuclear Information System (INIS)

    Naaman, O.; Teizer, W.; Dynes, R. C.

    2001-01-01

    We demonstrate Josephson tunneling in vacuum tunnel junctions formed between a superconducting scanning tunneling microscope tip and a Pb film, for junction resistances in the range 50--300 k Omega. We show that the superconducting phase dynamics is dominated by thermal fluctuations, and that the Josephson current appears as a peak centered at small finite voltage. In the presence of microwave fields (f=15.0 GHz) the peak decreases in magnitude and shifts to higher voltages with increasing rf power, in agreement with theory

  20. Tunneling junction as an open system. Normal tunneling

    International Nuclear Information System (INIS)

    Ono, Y.

    1978-01-01

    The method of the tunneling Hamiltonian is reformulated in the case of normal tunneling by introducing two independent particle baths. Due to the baths, it becomes possible to realize a final stationary state where the electron numbers of the two electrodes in the tunneling system are maintained constant and where there exists a stationary current. The effect of the bath-system couplings on the current-voltage characteristics of the junction is discussed in relation to the usual expression of the current as a function of voltage. (Auth.)

  1. Frequency driven inversion of tunnel magnetoimpedance and observation of positive tunnel magnetocapacitance in magnetic tunnel junctions

    International Nuclear Information System (INIS)

    Parui, Subir; Ribeiro, Mário; Atxabal, Ainhoa; Llopis, Roger; Bedoya-Pinto, Amilcar; Sun, Xiangnan; Casanova, Fèlix; Hueso, Luis E.

    2016-01-01

    The relevance for modern computation of non-volatile high-frequency memories makes ac-transport measurements of magnetic tunnel junctions (MTJs) crucial for exploring this regime. Here, we demonstrate a frequency-mediated effect in which the tunnel magnetoimpedance reverses its sign in a classical Co/Al 2 O 3 /NiFe MTJ, whereas we only observe a gradual decrease in the tunnel magnetophase. Such effects are explained by the capacitive coupling of a parallel resistor and capacitor in the equivalent circuit model of the MTJ. Furthermore, we report a positive tunnel magnetocapacitance effect, suggesting the presence of a spin-capacitance at the two ferromagnet/tunnel-barrier interfaces. Our results are important for understanding spin transport phenomena at the high frequency regime in which the spin-polarized charge accumulation due to spin-dependent penetration depth at the two interfaces plays a crucial role.

  2. Frequency driven inversion of tunnel magnetoimpedance and observation of positive tunnel magnetocapacitance in magnetic tunnel junctions

    Energy Technology Data Exchange (ETDEWEB)

    Parui, Subir, E-mail: s.parui@nanogune.eu, E-mail: l.hueso@nanogune.eu; Ribeiro, Mário; Atxabal, Ainhoa; Llopis, Roger [CIC nanoGUNE, 20018 Donostia-San Sebastian (Spain); Bedoya-Pinto, Amilcar [CIC nanoGUNE, 20018 Donostia-San Sebastian (Spain); Max Planck Institute of Microstructure Physics, D-06120 Halle (Germany); Sun, Xiangnan [CIC nanoGUNE, 20018 Donostia-San Sebastian (Spain); National Center for Nanoscience and Technology, 100190 Beijing (China); Casanova, Fèlix; Hueso, Luis E., E-mail: s.parui@nanogune.eu, E-mail: l.hueso@nanogune.eu [CIC nanoGUNE, 20018 Donostia-San Sebastian (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao (Spain)

    2016-08-01

    The relevance for modern computation of non-volatile high-frequency memories makes ac-transport measurements of magnetic tunnel junctions (MTJs) crucial for exploring this regime. Here, we demonstrate a frequency-mediated effect in which the tunnel magnetoimpedance reverses its sign in a classical Co/Al{sub 2}O{sub 3}/NiFe MTJ, whereas we only observe a gradual decrease in the tunnel magnetophase. Such effects are explained by the capacitive coupling of a parallel resistor and capacitor in the equivalent circuit model of the MTJ. Furthermore, we report a positive tunnel magnetocapacitance effect, suggesting the presence of a spin-capacitance at the two ferromagnet/tunnel-barrier interfaces. Our results are important for understanding spin transport phenomena at the high frequency regime in which the spin-polarized charge accumulation due to spin-dependent penetration depth at the two interfaces plays a crucial role.

  3. Aespoe HRL. Experiences of blasting of the TASQ tunnel

    International Nuclear Information System (INIS)

    Olsson, Mats; Niklasson, Bengt; Wilson, Lasse; Andersson, Christer; Christiansson, Rolf

    2004-11-01

    A new tunnel was developed at the Aespoe Hard Rock Laboratory (AHRL) during the spring and summer 2003. The tunnel was specially designed for a rock mechanics experiment, the Aespoe Pillar Stability Experiment (APSE). In this pillar experiment there was a high demand to initiate high in-situ stresses and therefore the tunnel was designed with a large height/ width ratio and with a circular floor. There were high requirements on bore hole precision and of a minimized EDZ (Excavation damaged zone) in the pillar area. This included a maximum borehole deviation of 10 mm/m, a maximum overbreak due to the lookout angle of 0.3 m and an EDZ of 0.3 m. To make a charge control feasible cartridged explosives was prescribed. The initiation was made with Nonel. The last three rounds used electronic initiation to enable studies of possibility to further reduce the EDZ. The collar of the tunnel was very close to installations and shaft and it was very important to avoid fly-rock and vibrations. Special types of stemming were used as well as steel plates and rubber mats. The excavation works was divided in three different phases. The first phase of the tunnel was an ordinary 26 m 2 tunnel. After approximately 30 m a ramp separated the tunnel section into a top heading and a bench, total 33 m 2 . After the last top heading round was excavated and the roof had been reinforced with fibre reinforced shotcrete the bench was taken out with horizontal holes as the third phase. The drilling precision was very good and 95% of all half-pipes fulfilled the demands. The total amount of visible half-pipes in the APSE-tunnel was high and indicated a successful smooth blasting. The EDZ was examined further by cutting slots in the wall and roof. Existing cracks appear very clearly when a dye penetrant is sprayed on the cleaned surface. A typical crack pattern consists of blast cracks, induced cracks (cracks from the distressing caused by blasting) and natural cracks. The maximum crack length in

  4. Aespoe HRL. Experiences of blasting of the TASQ tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Mats [Swebrec, Luleaa (Sweden); Niklasson, Bengt [Skanska Teknik, Stockholm (Sweden); Wilson, Lasse [Skanska Stora Projekt, Stockholm (Sweden); Andersson, Christer; Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2004-11-01

    length in the tunnel wall was roughly 0.2 m. However, longer cracks existed but these cracks probably originate from water filled blast holes. The cracks from the bench were generally much shorter than what is normally achieved during excavation of a horse-shoe shaped tunnel. This may be due to the stress situation under the arched bottom profile, the height requirement on drilling precision also in the floor as well as the low confinement in the arch shaped contour of the floor: Some conclusions from the APSE tunnel: There is a demand for new drilling equipment with a better guidance control to increase the drilling accuracy. Electronic detonators have very good accuracy and a high potential to reduce cracks from blasting. However, they must be more easy to use. It is possible to minimize the damage zone in the floor by using top heading and bench. However, there is a demand for more development in order to minimize the damage zone in the floor without a separate bench. Water in bore holes increases the damage zone in terms of length and frequency of induced fractures. This could be avoided by drilling the holes pointing slightly upwards. The look-out angle and distribution of specific charge along each round causes a discontinuous EDZ along the tunnel. It is therefore indicated that the impact of the EDZ on hydraulic conductivity along the tunnel has very limited impact. During similar conditions is it believed that the extent of the EDZ is manageable through DandB design and QA control during excavation.

  5. Fracturing of revision of a cobalt-chrome femoral head after fracturing of a ceramic femoral head, with diffuse metallosis. Case report

    Directory of Open Access Journals (Sweden)

    Pedro Miguel Dantas Costa Marques

    2013-04-01

    Full Text Available We presente a case of a fracture of a cobalt-chrome femoral head after revision of a hip total prosthesis with ceramic femoral head fracture. During surgery we found the cobalt-chrome femoral head fracture, wear of the polyethylene and massive metallosis in muscular and cartilaginous tissue. Both femoral stem and acetabular cup were stable and without apparent wearing. After surgical debridement, we promoted the substitution of the femoral head and the acetabular polyethylene by similar ones. After 12 months of follow-up, the patient has no pain complaints, function limit or systemic signs associated with malign metallosis

  6. Femoral shaft bowing in the coronal plane has more significant effect on the coronal alignment of TKA than proximal or distal variations of femoral shape.

    Science.gov (United States)

    Kim, Jong-Min; Hong, Soo-Heon; Kim, Jong-Min; Lee, Bum-Sik; Kim, Dong-Eun; Kim, Kyung-Ah; Bin, Seong-Il

    2015-07-01

    The aim of this study was to determine (1) variations in the shape of the proximal, middle, and distal femur in a series of Korean patients who had undergone total knee arthroplasty (TKA), (2) the preoperative relationship between these three parameters and the distal valgus cutting angle referenced off the femoral intramedullary guide, and (3) whether there was any relationship between femoral bowing and variations in the shape of the proximal or distal femur in the coronal plane. The preoperative long-standing anteroposterior radiographs of 316 consecutive osteoarthritis patients who underwent primary TKA from 2009 to 2011 were examined. The femoral neck shaft angle, the femoral shaft bowing angle, and the mechanical lateral distal femoral angle were measured to assess the shape of the proximal, middle, and distal femur, respectively. The valgus cutting angle of the femur was defined as the angle between the distal anatomical and mechanical axes of the femur. The study population showed large variations in femoral shape. The mean femoral intramedullary guide angle was 6.5° ± 1.3° (range: 4°-13°). The femoral shaft bowing angle was the factor that showed the strongest correlation with this angle (P shaft angle showed no correlation (n.s.). The femoral shaft bowing angle showed a weak correlation with the mechanical lateral distal femoral angle (P = 0.001), but was not significantly correlated with the femoral neck shaft angle (n.s.). Apparent femoral bowing (>3° of lateral or medial bowing) was found in 42 (13.3 %) of cases (37 cases of lateral bowing and five of medial bowing). Cases with lateral apparent femoral bowing >3° had a distal cutting angle of 8.6° ± 2.2° relative to the femoral intramedullary guide. The femoral intramedullary guide angle was mainly influenced by femoral shaft bowing among femoral deformities in the coronal plane. Therefore, to increase the accuracy of distal femoral cut during TKA, it is necessary to confirm femoral

  7. A biomechanical comparison of proximal femoral nails and locking proximal anatomic femoral plates in femoral fracture fixation A study on synthetic bones

    Directory of Open Access Journals (Sweden)

    Korhan Ozkan

    2015-01-01

    Conclusion: The proximal femoral intramedullary nail provides more stability and allows for earlier weight bearing than the locking plate when used for the treatment of unstable intertrochanteric fractures of the femur. Clinicians should be cautious for early weight bearing with locking plate for unstable intertrochanteric femur fractures.

  8. Scaling analysis of the non-Abelian quasiparticle tunneling in [Formula: see text] FQH states.

    Science.gov (United States)

    Li, Qi; Jiang, Na; Wan, Xin; Hu, Zi-Xiang

    2018-06-27

    Quasiparticle tunneling between two counter propagating edges through point contacts could provide information on its statistics. Previous study of the short distance tunneling displays a scaling behavior, especially in the conformal limit with zero tunneling distance. The scaling exponents for the non-Abelian quasiparticle tunneling exhibit some non-trivial behaviors. In this work, we revisit the quasiparticle tunneling amplitudes and their scaling behavior in a full range of the tunneling distance by putting the electrons on the surface of a cylinder. The edge-edge distance can be smoothly tuned by varying the aspect ratio for a finite size cylinder. We analyze the scaling behavior of the quasiparticles for the Read-Rezayi [Formula: see text] states for [Formula: see text] and 4 both in the short and long tunneling distance region. The finite size scaling analysis automatically gives us a critical length scale where the anomalous correction appears. We demonstrate this length scale is related to the size of the quasiparticle at which the backscattering between two counter propagating edges starts to be significant.

  9. Quantum tunneling of massive flux lines in a high-T{sub c} superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Gaber, M.W.; Achar, B.N.N. [Memphis Univ., TN (United States)

    1999-02-01

    We have investigated the quantum tunneling of damped flux lines of finite mass at T = 0 by extending our previous study of tunneling around T{sub 0}, the transition temperature. In the case of a cubic pinning potential, considered here, the action could be evaluated in a closed form for a flux line of finite length. The tunneling rate reaches a finite limit at T = 0, although it is temperature dependent and exhibits a 1/T variation near T{sub 0}. (orig.) 21 refs.

  10. [A method to avoid lengthening lower limbs after total hip arthroplasty in patients with congenital short femoral neck].

    Science.gov (United States)

    Chen, Tao; Shang, Xifu; He, Rui; Hu, Fei; Ge, Chang

    2012-03-01

    To investigate the method to avoid lengthening lower limbs after total hip arthroplasty in patients with congenital short femoral neck. The clinical data were analyzed retrospectively from 38 patients undergoing unilateral total hip arthroplasty between April 2005 and December 2010. There were 26 males and 12 females, aged 45-78 years (mean, 62.3 years). Among these cases, there were 11 cases of avascular necrosis of the femoral head, 17 cases of hip osteoarthritis, and 10 cases of femoral neck fracture. Before operation, 29 cases had leg length discrepancy; and the shortened length of the legs was 10-24 mm with an average of 14.5 mm by clinical measurement, and was 11-25 mm with an average of 14.7 mm by X-ray film measurement. The Harris score before operation was 44.0 +/- 3.6. At 1 day after operation, 3 cases had legs lengthening by clinical and X-ray film measurement; limb length difference less than 10 mm was regarded as equal limb length in the other 35 patients (92.1%). All incisions healed by first intention, and no complication of infection or lower limb deep venous thrombosis occurred. In 3 patients who had legs lengthening, 1 patient had abnormal gait and slight limping after increasing heel pad because the lower limb was lengthened by 16 mm, and 2 patients had slight limping. The other patients could walk normally and achieved pain relief of hip. Thirty-six patients were followed up 12-68 months (mean, 43.8 months). The Harris score was 86.7 +/- 2.3 after 6 months, showing significant difference (t = 3.260, P = 0.031) when compared with that before operation. The X-ray films showed no prosthetic loosening or subsidence. For patients with congenital short femoral neck during total hip arthroplasty, the surgeons should pay attention to osteotomy plane determination, limb length measurement, and use of the prosthesis with collar to avoid the lengthening lower limbs.

  11. Comparative characteristics of osteosynthesis techniques in patients with comminuted diaphyseal femoral fractures

    Directory of Open Access Journals (Sweden)

    A. P. Barabash

    2013-01-01

    Full Text Available The comparative analysis of the results of the surgical treatment of 130 patients with closed comminuted unilateral diaphyseal femoral fractures, including assessment of anatomic functional outcomes of treatment according to the technique of the standardized investigations in traumatology and orthopedy and determination of quality of life according to SF-36 method is carried out. Osteosynthesis with the help of external fixation devices was performed in 36 patients, intramedullary interlocking osteosynthesis - in 57 patients, compression plating - in 37 patients. Level of anatomic functional rehabilitation of the patients in the early postoperative period made up 69-79 %, 6 months later increased up to 74-92%, and after the expiration of 12 months the level of rehabilitation reached 85-99%. During the treatment quality of life concerning physical component was within the limits from 36,8 up to 55,5 %, and concerning mental component - 54,3-60,8 %. After the expiration of a year increase in the parameters of physical and mental components up to 55,7 - 59,8 % and 57,2-65,8 % is detected respectively. In the group where the transosseous osteosynthesis technique was applied we got 93,7-95 % of positive outcomes, with the average disability period of 212,3±18,1 days. In 47,2 % of cases the following complications are observed: knee contracture - 7; inflammation of the soft tissues located near the transosseous fixators - 5 (13,9%; shortening of the limb less than 5% of its length - 3; false joint formation - 1; fracture union with formation of varus deformity in the femoral bone - 1. When using intramedullary interlocking osteosynthesis we had positive results in 96,5 % of cases, with the average period of disability 176±17,8 days. In 10,5 % cases the following complications are observed: suture sinus - 1(1,75 %; femoral osteomyelitis - 1; break of the design - 1; false joint formation - 1; knee contracture - 1; shortening of the limb less than 5

  12. Investigations of Tunneling for Field Effect Transistors

    OpenAIRE

    Matheu, Peter

    2012-01-01

    Over 40 years of scaling dimensions for new and continuing product cycles has introduced new challenges for transistor design. As the end of the technology roadmap for semiconductors approaches, new device structures are being investigated as possible replacements for traditional metal-oxide-semiconductor field effect transistors (MOSFETs). Band-to-band tunneling (BTBT) in semiconductors, often viewed as an adverse effect of short channel lengths in MOSFETs, has been discussed as a promising ...

  13. Trochanteric entry femoral nails yield better femoral version and lower revision rates-A large cohort multivariate regression analysis.

    Science.gov (United States)

    Yoon, Richard S; Gage, Mark J; Galos, David K; Donegan, Derek J; Liporace, Frank A

    2017-06-01

    Intramedullary nailing (IMN) has become the standard of care for the treatment of most femoral shaft fractures. Different IMN options include trochanteric and piriformis entry as well as retrograde nails, which may result in varying degrees of femoral rotation. The objective of this study was to analyze postoperative femoral version between three types of nails and to delineate any significant differences in femoral version (DFV) and revision rates. Over a 10-year period, 417 patients underwent IMN of a diaphyseal femur fracture (AO/OTA 32A-C). Of these patients, 316 met inclusion criteria and obtained postoperative computed tomography (CT) scanograms to calculate femoral version and were thus included in the study. In this study, our main outcome measure was the difference in femoral version (DFV) between the uninjured limb and the injured limb. The effect of the following variables on DFV and revision rates were determined via univariate, multivariate, and ordinal regression analyses: gender, age, BMI, ethnicity, mechanism of injury, operative side, open fracture, and table type/position. Statistical significance was set at pregression analysis revealed that a lower BMI was significantly associated with a lower DFV (p=0.006). Controlling for possible covariables, multivariate analysis yielded a significantly lower DFV for trochanteric entry nails than piriformis or retrograde nails (7.9±6.10 vs. 9.5±7.4 vs. 9.4±7.8°, pregression analysis. However, this is not to state that the other nail types exhibited abnormal DFV. Translation to the clinical impact of a few degrees of DFV is also unknown. Future studies to more in-depth study the intricacies of femoral version may lead to improved technology in addition to potentially improved clinical outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Three-year results after directional atherectomy of calcified stenotic lesions of the superficial femoral artery.

    Science.gov (United States)

    Minko, P; Buecker, A; Jaeger, S; Katoh, M

    2014-10-01

    To investigate the 3-year outcome of patients with peripheral arterial disease (PAD) and heavily calcified stenotic lesions of the superficial femoral artery after directional atherectomy. Fifty-three patients (mean age 67 ± 10 years; 18 females, 35 males, TASC B and C, mean lesion length 7.9 ± 3.5 cm) with PAD (Rutherford 2-6) were enrolled into this prospective monocentric study. In total, 59 calcified lesions of the superficial femoral artery were treated with the Silverhawk atherectomy device (Covidien, Plymouth, MN, USA). Patients were followed-up for 36 months with a 6-month interval to perform clinical re-evaluation, including measurement of maximum walking distance and ankle-brachial index (ABI) as well as duplex-sonography. The primary success rate of the procedure was 92 %. In five cases (8 %), additional balloon-PTA and/or stent-PTA was necessary. Procedure-related embolization occurred in seven cases (12 %), which were all successfully treated by aspiration. The primary patency rate after 3 years was 55 %. Median Rutherford score decreased significantly from 5 to 0 after 36 months (p atherectomy was successfully applied to decrease the plaque burden. Results after 3 years showed a significant decrease of Rutherford score with persistent improvement of ABI and reasonable patency rate.

  15. Biomechanical considerations in slipped capital femoral epiphysis and insights into prophylactic fixation.

    Science.gov (United States)

    Leblanc, E; Bellemore, J M; Cheng, T; Little, D G; Birke, O

    2017-04-01

    Slipped capital femoral epiphysis (SCFE) is a deformity of the proximal femur secondary to widened and unstable physis. In stabilising the slip, gold standard treatments stop growth and involve premature physeal closure, which prevents the remodelling of the acquired deformity and creates a leg length discrepancy that may be significant in younger patients. We measured the impact of placing threaded screws across the proximal femoral physis by measuring the centre-trochanteric distance (CTD) and articulo-trochanteric distance (ATD) in participants with or without prophylactic fixation. We then compared the mechanical performance of static (stainless and titanium cannulated Synthes screws) and potentially growing implants (Synthes SCFE screw and Pega Medical Free Gliding screw) in a validated synthetic bone model. In the review of 30 non-fixed and 60 fixated hips over a mean follow-up of 1.9 years, we have noted a significant difference in pre/post CTD and ATD, as well as the change in CTD and ATD over time. In the biomechanical study, the newer implants allowing growth (Synthes SCFE screw and Pega Medical Free Gliding screw) were both shown to be at least non-inferior. The primary deformity of a SCFE in itself alters hip mechanics. Also, as confirmed in this study, there is a secondary deformity that is created by static fixation and relative trochanteric overgrowth. To help remodel mild deformities and prevent secondary trochanteric overgrowth, growing implants seem to be non-inferior to the more standard means of fixation in static testing.

  16. 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.

  17. Imaging appearance of entrapped periosteum within a distal femoral Salter-Harris II fracture

    International Nuclear Information System (INIS)

    Chen, Johnathan; Abel, Mark F.; Fox, Michael G.

    2015-01-01

    Salter Harris II fractures of the distal femur are associated with a high incidence of complications, especially premature physeal closure. Many risk factors for this high rate of premature physeal closure have been proposed. More recently, entrapment of periosteum within the physis has been suggested as an additional predisposing factor for premature physeal closure. The radiographic diagnosis of entrapped soft tissues, including periosteum, can be suggested in the setting of a Salter-Harris II fracture when the fracture does not reduce and physeal widening >3 mm remains. We report a patient who sustained a distal femoral Salter-Harris II fracture following a valgus injury. The patient had persistent distal medial physeal widening >5 mm following attempted reduction. A subsequent MRI revealed a torn periosteum entrapped within the distal femoral physis. Following removal of the periosteum, the patient developed a leg length discrepancy which required physiodesis of the contralateral distal femur. We present this case to raise awareness of the importance of having a high index of suspicion of periosteal entrapment in the setting of Salter-Harris II fractures since most consider entrapped periosteum an indication for surgery. (orig.)

  18. Design and analysis of the tunnel connecting the beam corridor and the spectrum hall of the CSNS

    International Nuclear Information System (INIS)

    Liu Jian; Wang Qingbin; Wu Qingbiao; Ma Zhongjian

    2011-01-01

    There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project. The length of the tunnel is about 20 m. The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered by soil for shielding. In order to reduce the dose rate at the exit of the cable ducts, we use the ISIS construction, which is designed with four turnings, as a reference for the tunnel design. The thickness of the shielding is obtained by a simulation with the Monte Carlo Code FLUKA. The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved. This paper provides the basis for the design of the tunnel. (authors)

  19. Case report: AVN of the femoral head five year follow-up of the combination of ipsilateral femoral neck and sub-trochanteric fracture.

    Science.gov (United States)

    Zhang, Wei; Zhu, Feng; Dong, Hanqing; Xu, Yaozeng

    2016-04-01

    To our knowledge, the type of combination of ipsilateral femoral neck and sub-trochanteric fracture is rare. And the long term follow-up is seldom been reported. A 60 year old woman suffered from a traffic accident. We gave her the intramedullary nail treatment for the combination of ipsilateral femoral neck and sub-trochanteric fracture, and the fracture indeed cured after one year and there is no clue of necrosis of the femoral head, but after 5 years, there is an evidence of necrosis of the femoral head. Combination of ipsilateral femoral neck and sub-trochanteric fracture should be kept in mind. Patients with this unusual fracture should be kept under surveillance for longer than might be thought currently to be necessary for there is a possibility of necrosis of the femoral head, even a nondisplaced femoral neck fracture.

  20. Femoral neck radiography: effect of flexion on visualization

    International Nuclear Information System (INIS)

    Garry, S.C.; Jhangri, G.S.; Lambert, R.G.W.

    2005-01-01

    To determine whether flexion improves radiographic visualization of the femoral neck when the femur is externally rotated. Five human femora, with varying neck-shaft and anteversion angles, were measured and immobilized. Degree of flexion required to bring the femoral neck horizontal was measured, varying the rotation. Next, one bone was radiographed in 16 positions, varying rotation in 15 o and flexion in 10 o increments. Radiographs were presented in randomized blinded fashion to 15 staff radiologists for scoring of femoral neck visualization. Following this, all 5 bones were radiographed in 4 positions of rotation and at 0 o and 20 o flexion, and blinded randomized review of radiographs was repeated. Comparisons between angles and rotations were made using the Mann-Whitney test. The flexion angle required to bring the long axis of the femoral neck horizontal correlated directly with the degree of external rotation (ρ o internal rotation to 30 o external rotation (ρ o flexion was applied to bones in external rotation, visualization significantly improved at 15 o (ρ o (ρ o ) of flexion can significantly improve radiographic visualization. This manoeuvre could be useful for radiography of the femoral neck when initial radiographs are inadequate because of external rotation of the leg. (author)

  1. Avascular necrosis of the femoral head in HIV infected patients

    Directory of Open Access Journals (Sweden)

    Marcos Almeida Matos

    Full Text Available Avascular necrosis (AVN of the femoral head is an emerging complication in HIV infected patients. It has been suggested that the increased incidence of AVN in this population may be caused by an increased prevalence of predisposing factors for osteonecrosis, including protease inhibitors, hyperlipidemia, corticosteroid use, alcohol and intravenous drug abuse. The aim of this study was to assess the risk factors for avascular necrosis developing in the femoral head of HIV infected individuals. This study consisted of meta-analysis of the secondary data extracted from current literature. The selected articles allowed two study groups to be drawn up for comparison. Group 1 comprised 324 individuals infected by the HIV virus, who did not present femoral head AVN. Group 2 comprised 32 HIV positive patients, who presented femoral head AVN. The parameters used for analysis were as follows: age, gender, sexual preference, use of intravenous drugs, time of diagnosis, CD4+ cell count, use of antiretroviral agents and duration, serum cholesterol and serum triglycerides. The present study found a statistically significant association between hypertriglyceridemia, hypercholesterolemia, sexual preference and intravenous drug abuse. The authors concluded that femoral head osteonecrosis is associated with hyperlipidemia (hypercholesterolemia and hypertriglyceridemia and intravenous drug abuse. This study supports the hypothesis that protease inhibitors play a role in the development of osteonecrosis through a tendency to cause hyperlipidemia.

  2. Valgus Slipped Capital Femoral Epiphysis in Patient with Hypopituitarism

    Directory of Open Access Journals (Sweden)

    Yoshihiro Kotoura

    2017-01-01

    Full Text Available Slipped capital femoral epiphysis (SCFE is a common disease of adolescent and the epiphysis is positioned more posteromedially in relation to the femoral neck shaft with varus SCFE; however, posterolateral displacement of the capital epiphysis, valgus SCFE, occurs less frequently. We report a case of valgus SCFE in a 17-year-old boy with hypopituitarism. After falling down, he experienced difficulty in walking. The radiographs were inconclusive; however three-dimensional computed tomography images showed lateral displacement of the epiphysis on the right femoral head. Valgus SCFE was diagnosed. The patient underwent in situ pinning of both sides. In situ pinning on the left side was performed as a prophylactic pinning because of endocrine abnormalities. At the 1-year follow-up, he could walk without any difficulty and there were no signs of pain. The epiphysis is commonly positioned more posteromedially in relation to the femoral neck shaft with most SCFE, but, in this case, the epiphysis slipped laterally. Differential diagnosis included femoral neck fracture (Delbet-Colonna type 1; however, this was less likely due to the absence of other clinical signs. Therefore, we diagnosed the patient as SCFE. When children complain of leg pain and limp, valgus SCFE that may not be visualized on anteroposterior radiographs needs to be considered.

  3. Clinical use of femoral artery hemostasis sticking after interventional procedure via femoral artery access

    International Nuclear Information System (INIS)

    Zhu Zhongsheng; Chen Shaoliang; Ye Fei; Zhang Junjie; Zhou Jie; Tian Nailiang; Lin Song; Liu Zhizhong; Xiao Pingxi; Qu Hong

    2010-01-01

    Objective: To observe the clinical effect of the use of femoral artery hemostasis sticking V+PAD after the interventional procedure via femoral artery access. Methods: By using random permutation list 80 patients, who decided to receive coronary angiography and percutaneous transluminal coronary angioplasty, were randomly selected. Of the 80 patients, hemostasis sticking V + PAD was employed in 40 patients with even numbers (trial group), only manual compression was adopted to stop bleeding in another 40 patients with odd numbers (control group). All the patients were informed about this trial and had to sign a consent letter. The pressure time, the treatment method of access site after hemostasis, the posture in bed, the immobilization time, the comfort degree of patients, the complications of access site prior to discharge, etc. were observed and the results were compared between two groups. Results: There was no significant difference between two groups as respect to age, gender ratios,activated clotting time (ACT) value and blood pressure. However, significantly difference in the compression time and bed rest time existed between the two groups. The compression time in trial group and control group was (7.9 ± 0.5) min and (19.8 ± 5.1) min respectively (P<0.01), while the bed rest time in trial group and control group was (6.1 ± 5.0) hours and (23.9 ± 0.2) hours respectively (P<0.01). All patients in trial group was supine in bed with the head side of the bed raised at 30 degree immediately after the procedure, and the head side of the bed was further raised to 90 degree one hour later. The puncture site was bandaged with conventional compression and immobilization was not employed. Patients could lie in bed with free posture and the patient's comfort degree was greatly improved. During hospitalization no complications related to puncture site occurred in all patients except one obese woman in trial group who developed pseudoaneurysm. Conclusion: Femoral

  4. Tunneling of Atoms, Nuclei and Molecules

    International Nuclear Information System (INIS)

    Bertulani, C.A.

    2015-01-01

    This is a brief review of few relevant topics on tunneling of composite particles and how the coupling to intrinsic and external degrees of freedom affects tunneling probabilities. I discuss the phenomena of resonant tunneling, different barriers seen by subsystems, damping of resonant tunneling by level bunching and continuum effects due to particle dissociation. (author)

  5. Computational Multiqubit Tunnelling in Programmable Quantum Annealers

    Science.gov (United States)

    2016-08-25

    ARTICLE Received 3 Jun 2015 | Accepted 26 Nov 2015 | Published 7 Jan 2016 Computational multiqubit tunnelling in programmable quantum annealers...state itself. Quantum tunnelling has been hypothesized as an advantageous physical resource for optimization in quantum annealing. However, computational ...qubit tunnelling plays a computational role in a currently available programmable quantum annealer. We devise a probe for tunnelling, a computational

  6. 78 FR 46117 - National Tunnel Inspection Standards

    Science.gov (United States)

    2013-07-30

    ... busiest vehicular tunnel in the world. The Fort McHenry Tunnel handles a daily traffic volume of more than... vehicular, transit, and rail tunnels in the New York City metropolitan area. Although it is still too early... congestion along alternative routes, and save users both dollars and fuel. If these tunnels were closed due...

  7. Een systeem voor classificatie van korte tunnels.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1985-01-01

    The most difficult problems in the lighting of tunnels occur in daylight and in particular in the entrance of the tunnel, while drivers approaching the tunnel must be able to look into the tunnel from the outside to detect the road course and eventual obstacles. A classification should The made on

  8. Tunnel fire testing and modeling the Morgex North tunnel experiment

    CERN Document Server

    Borghetti, Fabio; Gandini, Paolo; Frassoldati, Alessio; Tavelli, Silvia

    2017-01-01

    This book aims to cast light on all aspects of tunnel fires, based on experimental activities and theoretical and computational fluid dynamics (CFD) analyses. In particular, the authors describe a transient full-scale fire test (~15 MW), explaining how they designed and performed the experimental activity inside the Morgex North tunnel in Italy. The entire organization of the experiment is described, from preliminary evaluations to the solutions found for management of operational difficulties and safety issues. This fire test allowed the collection of different measurements (temperature, air velocity, smoke composition, pollutant species) useful for validating and improving CFD codes and for testing the real behavior of the tunnel and its safety systems during a diesel oil fire with a significant heat release rate. Finally, the fire dynamics are compared with empirical correlations, CFD simulations, and literature measurements obtained in other similar tunnel fire tests. This book will be of interest to all ...

  9. Apparent tunneling in chemical reactions

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Hansen, Flemming Yssing; Billing, G. D.

    2000-01-01

    A necessary condition for tunneling in a chemical reaction is that the probability of crossing a barrier is non-zero, when the energy of the reactants is below the potential energy of the barrier. Due to the non-classical nature (i.e, momentum uncertainty) of vibrational states this is, however......, not a sufficient condition in order to establish genuine tunneling as a result of quantum dynamics. This proposition is illustrated for a two-dimensional model potential describing dissociative sticking of N-2 on Ru(s). It is suggested that the remarkable heavy atom tunneling, found in this system, is related...

  10. Seismic analysis of long tunnels: A review of simplified and unified methods

    Directory of Open Access Journals (Sweden)

    Haitao Yu

    2017-06-01

    Full Text Available Seismic analysis of long tunnels is important for safety evaluation of the tunnel structure during earthquakes. Simplified models of long tunnels are commonly adopted in seismic design by practitioners, in which the tunnel is usually assumed as a beam supported by the ground. These models can be conveniently used to obtain the overall response of the tunnel structure subjected to seismic loading. However, simplified methods are limited due to the assumptions that need to be made to reach the solution, e.g. shield tunnels are assembled with segments and bolts to form a lining ring and such structural details may not be included in the simplified model. In most cases, the design will require a numerical method that does not have the shortcomings of the analytical solutions, as it can consider the structural details, non-linear behavior, etc. Furthermore, long tunnels have significant length and pass through different strata. All of these would require large-scale seismic analysis of long tunnels with three-dimensional models, which is difficult due to the lack of available computing power. This paper introduces two types of methods for seismic analysis of long tunnels, namely simplified and unified methods. Several models, including the mass-spring-beam model, and the beam-spring model and its analytical solution are presented as examples of the simplified method. The unified method is based on a multiscale framework for long tunnels, with coarse and refined finite element meshes, or with the discrete element method and the finite difference method to compute the overall seismic response of the tunnel while including detailed dynamic response at positions of potential damage or of interest. A bridging scale term is introduced in the framework so that compatibility of dynamic behavior between the macro- and meso-scale subdomains is enforced. Examples are presented to demonstrate the applicability of the simplified and the unified methods.

  11. [Clinical analysis of LPFP, PFNA and BPH in treating femoral intertrochanteric fractures in elderly patients].

    Science.gov (United States)

    Zhu, Li-Jun; Li, Xiao-Fei; Liu, Chao; Lyu, Cheng-Yu

    2017-07-25

    To evaluate the clinical results of locking proximal femur plate(LPFP), proximal femoral nail antirotation(PFNA) and bipolar hemiarthroplasty(BPH) in the treatment of femoral intertrochanteric fractures in elderly patients. Retrospective analysis of the 86 elderly patients with femoral intertrochanteric fractures during June 2011 and August 2016 were enrolled in this study. The patients were divided into 3 groups: 26 cases in LPFP group included 10 males and 16 females with an average age of (72.54±4.78) years old, 5 cases of type II of Evans, 12 cases of type III and 9 cases of type IV; 39 cases in PFNA group included 17 males and 22 females with an average age of 74.41±5.65, 11 cases of type II, 18 cases of type III and 10 cases of type IV; 21 cases in BPH group included 9 males and 12 females with an average age of 76.23±6.97, 1 case of type II, 10 cases of type III and 10 cases of type IV. The data of three groups were collected for statistical analysis on the following aspects: operation time, intraoperative blood loss, the length of hospital stay, postoperative complications and Harris score of the hip joint function. The wound healed well and no complication occurred. Eighty-four cases were follow-up, while 2 cases were lost, the follow-up rate was 97.6%. The patients were followed up for 22 to 41 months with an average of 26.3 months. For comparison of operation time and time of the hospital stay, BPH group was shorter than the LPFP and PFNA group( F =19.782, 21.981, P BPH group was less blood loss than the LPFP and PFNA group( F =12.976, P 0.05). For comparison of the postoperative complications, LPFP group was higher than BHP and PFNA group( F =30.976, P 0.05). For comparison of the Harris score of the hip joint at 1 year after operation, BPH and PFNA group were both higher than LPFP group( F =19.692, P BPH and PFNA group ( t =4.971, P >0.05). For elder patient with femoral intertrochanteric fracture, BPH could be the best optional for the shorter

  12. Frequent complications and severe bone loss associated with the repiphysis expandable distal femoral prosthesis.

    Science.gov (United States)

    Cipriano, Cara A; Gruzinova, Irina S; Frank, Rachel M; Gitelis, Steven; Virkus, Walter W

    2015-03-01

    The treatment of choice for distal femur malignancies in skeletally immature patients remains controversial. An expandable endoprosthesis device (Repiphysis Limb Salvage System; Wright Medical Technology, Arlington, TN, USA) allows for limb preservation and noninvasive lengthening but has been associated with significant complications; however, the extent and implications of bone loss associated with this implant have not been reported. Our goals were to report (1) the 2-year minimum clinical outcomes after placement of the Repiphysis expandable prosthesis for pediatric distal femur malignancies; (2) the complications associated with this prosthesis; (3) the failure rate of this prosthesis; and (4) the revision alternatives available for salvage procedures. Between 2002 and 2010, one surgeon (SG) treated all skeletally immature patients (mean age, 10.1 years; range, 4.7-13.6 years) with distal femoral osteosarcoma using a Repiphysis expandable prosthesis. Of the 12 patients who met these criteria, two were excluded for death from disease before 2 years, and mean followup for the remaining 10 was 72 months (range, 26-119 months). Medical records were retrospectively reviewed for complications and clinical outcomes, as assessed by the Musculoskeletal Tumor Society (MSTS) scoring system. Radiographs at final followup were reviewed for bone loss and analyzed by the two senior authors (SG, WWV) to determine reconstruction options available for future revisions. MSTS scores averaged 67%, and we observed 37 implant-related complications requiring a total of 15 reoperations. Six patients underwent implant revisions with aseptic loosening being the predominant mode of failure; ultimately, four of these were converted to adult modular oncology prostheses, and two underwent total femoral replacements. Bone loss in this series was severe in terms of femoral length, cortical thinning, and metadiaphyseal compromise, and most patients will not have sufficient bone stock to permit

  13. Analytical model for vibration prediction of two parallel tunnels in a full-space

    Science.gov (United States)

    He, Chao; Zhou, Shunhua; Guo, Peijun; Di, Honggui; Zhang, Xiaohui

    2018-06-01

    This paper presents a three-dimensional analytical model for the prediction of ground vibrations from two parallel tunnels embedded in a full-space. The two tunnels are modelled as cylindrical shells of infinite length, and the surrounding soil is modelled as a full-space with two cylindrical cavities. A virtual interface is introduced to divide the soil into the right layer and the left layer. By transforming the cylindrical waves into the plane waves, the solution of wave propagation in the full-space with two cylindrical cavities is obtained. The transformations from the plane waves to cylindrical waves are then used to satisfy the boundary conditions on the tunnel-soil interfaces. The proposed model provides a highly efficient tool to predict the ground vibration induced by the underground railway, which accounts for the dynamic interaction between neighbouring tunnels. Analysis of the vibration fields produced over a range of frequencies and soil properties is conducted. When the distance between the two tunnels is smaller than three times the tunnel diameter, the interaction between neighbouring tunnels is highly significant, at times in the order of 20 dB. It is necessary to consider the interaction between neighbouring tunnels for the prediction of ground vibrations induced underground railways.

  14. Tunneling progress on the Yucca Mountain Project

    International Nuclear Information System (INIS)

    Hansmire, W.H.; Munzer, R.J.

    1996-01-01

    The current status of tunneling progress on the Yucca Mountain Project (YMP) is presented in this paper. The Exploratory Studies Facility (ESF), a key part of the YMP, has been long in development and construction is ongoing. This is a progress report on the tunneling aspects of the ESF as of January 1, 1996. For purposes of discussion in this summary, the tunneling has progressed in four general phases. The paper describes: tunneling in jointed rock under low stress; tunneling through the Bow Ridge Fault and soft rock; tunneling through the Imbricate Fault Zone; and Tunneling into the candidate repository formation

  15. Limb shortening osteotomy in a patient with achondroplasia and leg length difference after total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Christian L. Galata

    2013-07-01

    Full Text Available Introduction: Achondroplasia is the most common reason for disproportionate short stature. Normally, orthopedic limb lengthening procedures must be discussed in the course of this genetic disorder and have been successful in numerous achondroplastic patients in the past. In some cases, the disease may lead to leg length differences with need for surgical correction. Case Report: We report a case of achondroplastic dysplastic coxarthrosis with symptomatic leg length difference after bilateral total hip arthroplasty in a 52-year-old female patient, in which a distal femoral shortening osteotomy was successfully performed. Conclusion: Femoral shortening osteotomy is very uncommon in patients with achondroplasia. We conclude, however, that in rare cases it can be indicated and provide the advantage of shorter operation time, less perioperative complications and faster recovery compared to leg lengthening procedures. Keywords: Achondroplasia, dysplastic coxarthrosis, limb shortening, distal femur osteotomy.

  16. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  17. Tunnel magnetoresistance in asymmetric double-barrier magnetic tunnel junctions

    International Nuclear Information System (INIS)

    Useinov, N.Kh.; Petukhov, D.A.; Tagirov, L.R.

    2015-01-01

    The spin-polarized tunnel conductance and tunnel magnetoresistance (TMR) through a planar asymmetric double-barrier magnetic tunnel junction (DBMTJ) have been calculated using quasi-classical model. In DBMTJ nanostructure the magnetization of middle ferromagnetic metal layer can be aligned parallel or antiparallel with respect to the fixed magnetizations of the top and bottom ferromagnetic electrodes. The transmission coefficients of an electron to pass through the barriers have been calculated in terms of quantum mechanics. The dependencies of tunnel conductance and TMR on the applied voltage have been calculated in case of non-resonant transmission. Estimated in the framework of our model, the difference between the spin-channels conductances at low voltages was found relatively large. This gives rise to very high magnitude of TMR. - Highlights: • The spin-polarized conductance through the junction is calculated. • Dependencies of the tunnel conductance vs applied bias are shown. • Bias voltage dependence of tunnel magnetoresistance for the structure is shown

  18. Tunneling through landsliding zone; Jisuberi chitainai no tunnel seko

    Energy Technology Data Exchange (ETDEWEB)

    Konbu, A; Hatabu, K; Kano, T [Tekken Corp., Tokyo (Japan)

    1994-08-01

    At the new tunnel construction site of the Shirakata tunnel on the Obama line in Yamaguchi Prefecture, a landsliding occurred at about 60 meters to the upper portion obliquely to the right hand side of the shaft when the excavation progressed to about 10 meters from the starting side. The landslide caused displacement at the shaft opening and change in the supports. As a result of the re-investigation, it was confirmed that the slide face went through the tunnel cross section. The measures taken were removal of the upper soil and an adoption of the all ground fastening (AGF) method (injection type long tip fastening method) as an auxiliary construction to stop loosening of the natural ground associated with the tunnel excavation. The result was a completion of tunneling the landsliding zone without a problem. This paper reports the AGF method adopted in the above construction, together with the construction works and natural ground conditions. The AGF method is about the same as the pipe roof method with regard to the natural ground accepting mechanism and the materials used. The difference is building an improved body in a limited area in the natural ground around the steel pipes by injecting the fixing material. The use of this method caused no problems in subsidence and displacement in the surrounding ground, and completed the tunneling construction without an unusual event. 1 ref., 7 figs., 2 tabs.

  19. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  20. High Folic Acid Intake during Pregnancy Lowers Body Weight and Reduces Femoral Area and Strength in Female Rat Offspring

    Directory of Open Access Journals (Sweden)

    Pedro S. P. Huot

    2013-01-01

    Full Text Available Rats fed gestational diets high in multivitamin or folate produce offspring of altered phenotypes. We hypothesized that female rat offspring born to dams fed a gestational diet high in folic acid (HFol have compromised bone health and that feeding the offspring the same HFol diet attenuates these effects. Pregnant rats were fed diets with either recommended folic acid (RFol or 10-fold higher folic acid (HFol amounts. Female offspring were weaned to either the RFol or HFol diet for 17 weeks. HFol maternal diet resulted in lower offspring body weights (6%, P=0.03 and, after adjusting for body weight and femoral length, smaller femoral area (2%, P=0.03, compared to control diet. After adjustments, HFol pup diet resulted in lower mineral content (7%, P=0.01 and density (4%, P=0.002 of lumbar vertebra 4 without differences in strength. An interaction between folate content of the dam and pup diets revealed that a mismatch resulted in lower femoral peak load strength (P=0.01 and stiffness (P=0.002. However, the match in folate content failed to prevent lower weight gain. In conclusion, HFol diets fed to rat dams and their offspring affect area and strength of femurs and mineral quantity but not strength of lumbar vertebrae in the offspring.

  1. Relativistic length agony continued

    Directory of Open Access Journals (Sweden)

    Redžić D.V.

    2014-01-01

    Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

  2. A STUDY OF UNSTABLE INTERTROCHANTERIC FEMORAL FRACTURES TREATED BY TROCHANTERIC FEMORAL NAIL

    Directory of Open Access Journals (Sweden)

    Sreenivasa Neikar

    2017-11-01

    Full Text Available BACKGROUND Intertrochanteric fracture is one of the most common fracture of the hip especially in the elderly. The incidence of intertrochanteric fracture is rising because of the increase in number of elderly population along with superadded osteoporosis. MATERIALS AND METHODS Study included cases of unstable intertrochanteric fractures (AO and OTA Classification 31-A2 and 31-A3 fracture patterns that were operated with the short trochanteric femoral nail, which fitted into the inclusion criteria done in medical college hospital, Vijayanagara Institute of Medical Sciences, Bellary, from February 2015 to September 2016. RESULTS The age distribution was from 40 to 80 years. The largest group of patients were from 61 to 70 years. The average age was 60.5 years. The number of male patients in our series was 20 (66.7% and female was 10 (33.3%. Right side was affected in 11 cases (36.7% and left side in 19 cases (63.3%. Good reduction was achieved in 23 patients (76.7%. Acceptable reduction was achieved in 7 (23.3% patients due to severe comminution. In our study, 25 patients (83.33% had no complications. We encountered one intraoperative complication in the form of greater trochanter splintering, while inserting the nail. In our study, we encountered following postoperative complications. We noticed one case of delayed union, one case of Z effect and 2 cases of varus malunion. CONCLUSION We conclude that short trochanteric femoral nail provides good fixation for unstable intertrochanteric fractures if proper preoperative planning, good reduction and surgical technique are followed leading to high rate of bone union and minimal soft tissue damage especially for Asian patients with relatively small femora.

  3. A Case of Late Femoral Pseudoaneurysm Caused by Stent Disconnection

    International Nuclear Information System (INIS)

    Rivolta, Nicola; Fontana, Federico; Piffaretti, Gabriele; Tozzi, Matteo; Carrafiello, Gianpaolo

    2010-01-01

    We present the case of a late superficial femoral artery stent disconnection causing an asymptomatic pseudoaneurysm successfully treated with a stent-graft. A 67-year-old female was referred to our department for evaluation of claudication of the left lower limb and was diagnosed to have a total occlusion of the superficial femoral artery. Three nitinol stents were used to revascularize this artery. At 48 months, duplex-ultrasonography control revealed the presence of a 45-mm saccular femoral dilatation; X-rays and CT angiography showed fractures of the proximal stents and the presence of a pseudoaneurysm at the site of the distal stents disconnection. The pseudoaneurysm was excluded using two stent-grafts. We conclude that patients and surgeons should be aware of structural complications with all stents. Rigorous follow-up controls should be mandatory. Endovascular repair proved to be feasible and durable to manage a previous endovascular procedure.

  4. Femoral arteriographic finding in acute ergotism: Report of A Case

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, H S; Lee, K N; Cha, S B [St. Mary' s Hospital, Catholic Medical College, Seoul (Korea, Republic of)

    1971-10-15

    A case of acute ergotism with angiographic demonstration of bilateral femoral artery involvement is reported. A 27-year-old married woman was admitted because of sudden onset of severe pain in both flanks and lower legs, followed by numbness and coldness of the skin on both legs. The attack occurred after the administration of ergot tartrate as postpartum care. Femoral arteriography was performed on 10th day of illness with the Seldinger technic. The femoral arteries were generally smaller in caliber than normal. There was no definite evidence of occlusive disease. Findings were more or less symmetrical and extended to lower legs where only fine branches were visualized. The final diagnosis was diffuse vasospasm due to acute ergotism with secondary occlusion of the arteries of lower leg bilaterally.

  5. Emergency Stenting of a Ruptured Infected Anastomotic Femoral Pseudoaneurysm

    International Nuclear Information System (INIS)

    Klonaris, Chris; Katsargyris, Athanasios; Matthaiou, Alexandros; Giannopoulos, Athanasios; Tsigris, Chris; Papadopouli, Katerina; Tsiodras, Sotiris; Bastounis, Elias

    2007-01-01

    A 74-year-old man presented with a ruptured infected anastomotic femoral pseudoaneurysm. Due to severe medical comorbidities he was considered unsuitable for conventional surgical management and underwent an emergency endovascular repair with a balloon-expandable covered stent. The pseudoaneurysm was excluded successfully and the patient had an uneventful postoperative recovery with long-term suppressive antimicrobials. He remained well for 10 months after the procedure with no signs of recurrent local or systemic infection and finally died from an acute myocardial infarction. To our knowledge, emergency endovascular treatment of a free ruptured bleeding femoral artery pseudoaneurysm has not been documented before in the English literature. This case illustrates that endovascular therapy may be a safe and efficient alternative in the emergent management of ruptured infected anastomotic femoral artery pseudoaneurysms when traditional open surgery is contraindicated

  6. Femoral arteriographic finding in acute ergotism: Report of A Case

    International Nuclear Information System (INIS)

    Rhee, H. S.; Lee, K. N.; Cha, S. B.

    1971-01-01

    A case of acute ergotism with angiographic demonstration of bilateral femoral artery involvement is reported. A 27-year-old married woman was admitted because of sudden onset of severe pain in both flanks and lower legs, followed by numbness and coldness of the skin on both legs. The attack occurred after the administration of ergot tartrate as postpartum care. Femoral arteriography was performed on 10th day of illness with the Seldinger technic. The femoral arteries were generally smaller in caliber than normal. There was no definite evidence of occlusive disease. Findings were more or less symmetrical and extended to lower legs where only fine branches were visualized. The final diagnosis was diffuse vasospasm due to acute ergotism with secondary occlusion of the arteries of lower leg bilaterally

  7. Avascular Necrosis of the Femoral Head: Are Any Genes Involved?

    Science.gov (United States)

    Pouya, Farzaneh; Kerachian, Mohammad Amin

    2015-01-01

    Avascular necrosis of the femoral head (ANFH) is a pathologic process that results from interruption of blood supply to the femur bone resulting in the death of bone cells and collapse of the femoral head. Nontraumatic ANFH continues to be a significant challenge to orthopedic surgeons. While the exact mechanisms remain elusive, many new insights have emerged from research in the last decade that has given us a clearer picture of the pathogenesis of nontraumatic ANFH. Progression to the end stage of ANFH appears to be related to five main mechanisms: hypercoagulable conditions, angiogenesis suppressions, hyperadipogenesis, heritable states, and switching the bone remodelling into bone resorption. Researchers have been examining the pathogenic mechanisms of ANFH but none of these theories have been firmly confirmed although some appear more plausible than the others. All of these factors can switch bone remodelling into bone resorption, which can further lead to ANFH progression ending up to femoral head collapse. PMID:26213697

  8. Assessment of femoral head perfusion by dynamic MR imaging

    International Nuclear Information System (INIS)

    Ochi, Ryuya; Nakano, Tetsuo; Miyazono, Kazuki; Tsurugami, Hiroshi; Fukuda, Tomohiro; Inaba, Daisuke; Takada, Koji

    2004-01-01

    We studied femoral head perfusion in 21 femoral neck fractures using dynamic MR imaging (MRI) between November 2001 and July 2002. MRI patterns divided into four groups when the results between the fractured side and unaffected side were compared. Femoral head perfusion at the fractured side was normal in Type A, about half in Type B, and absent in Type C. When perfusion at both the fractured side and unaffected side was absent, Exceptional Type was suspected. The Garden I group consisted of one Type B. The Garden II group consisted of one Type A, six Type B, one Type C, and two Exceptional Type. The Garden III group consisted of two Type B and one Type C, and the Garden IV group consisted of six Type C and one Exceptional Type. Post operations of by internal fixation confirmed the incidence of aseptic necrosis using MRI. (author)

  9. A cementless, proximally fixed anatomic femoral stem induces high micromotion with nontraumatic femoral avascular necrosis: A finite element study

    Directory of Open Access Journals (Sweden)

    Wen-Chuan Chen

    2014-07-01

    Full Text Available Decrease in bone mineral density of metaphysis in patients with nontraumatic avascular necrosis of the femoral head (AVN is considered the main factor leading to aseptic loosening of the femoral component. Researchers have hypothesized that a cementless, anatomic stem fixed proximally to the metaphysis has a higher risk for aseptic loosening than a straight stem that is fixed at the diaphysis in patients with nontraumatic AVN. The purpose of the current study was to evaluate the effects of cancellous bone stiffness at the metaphysis and stem geometry on the micromotion of the femoral stem relative to the femur. The VerSys (straight and ABG (anatomic femoral stems were enrolled in this finite element study to determine the performance of prosthetic micromotion. The simulated load to the hip joint during heel strike was assigned. Results showed that the VerSys model represented better resistance in micromotion between the bone/stem interface than the ABG model in either normal or poor cancellous bone stiffness at the metaphysis. The bone quality at the metaphysis of patients with nontraumatic AVN should be considered prior to selecting a femoral stem. In consideration of initial stability, acementless, straight stem that fits the isthmus is more favourable than an anatomic stem that is fixed to the proximal area of the canal.

  10. A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

    Science.gov (United States)

    Jenkins, Paul J; Ramaesh, Rishikesan; Pankaj, Pankaj; Patton, James T; Howie, Colin R; Goffin, Jérôme M; Merwe, Andrew van der; Wallace, Robert J; Porter, Daniel E; Simpson, A Hamish

    2013-10-01

    The micro-architecture of bone has been increasingly recognized as an important determinant of bone strength. Successful operative stabilization of fractures depends on bone strength. We evaluated the osseous micro-architecture and strength of the osteoporotic human femoral head. 6 femoral heads, obtained during arthroplasty surgery for femoral neck fracture, underwent micro-computed tomography (microCT) scanning at 30 μm, and bone volume ratio (BV/TV), trabecular thickness, structural model index, connection density, and degree of anisotropy for volumes of interest throughout the head were derived. A further 15 femoral heads underwent mechanical testing of compressive failure stress of cubes of trabecular bone from different regions of the head. The greatest density and trabecular thickness was found in the central core that extended from the medial calcar to the physeal scar. This region also correlated with the greatest degree of anisotropy and proportion of plate-like trabeculae. In the epiphyseal region, the trabeculae were organized radially from the physeal scar. The weakest area was found at the apex and peripheral areas of the head. The strongest region was at the center of the head. The center of the femoral head contained the strongest trabecular bone, with the thickest, most dense trabeculae. The apical region was weaker. From an anatomical and mechanical point of view, implants that achieve fixation in or below this central core may achieve the most stable fixation during fracture healing.

  11. Surgical strategies in polytraumatized patients with femoral shaft fractures - comparing a German and an Australian level I trauma centre.

    Science.gov (United States)

    Andruszkow, Hagen; Dowrick, Adam S; Frink, Michael; Zeckey, Christian; Krettek, Christian; Hildebrand, Frank; Edwards, Elton R; Mommsen, Philipp

    2013-08-01

    Femoral shaft fractures are one of the most common injuries in multiple trauma patients. Due to their prognostic relevance, there is an ongoing controversial discussion as to the optimal treatment strategy in terms of Damage Control Orthopaedics (DCO) and Early Total Care (ETC). We aimed to describe the differences in fracture management and clinical outcome of multiple trauma patients with concomitant femoral shaft fractures treated at a German and an Australian level I trauma centre using the same inclusion criteria. Polytraumatized patients (ISS ≥ 16) with a femoral shaft fracture aged ≥ 16 years treated at a German and an Australian trauma centre between 2003 and 2007 were included. According to ETC and DCO management principles, we evaluated demographic parameters as well as posttraumatic complications and clinical outcome. Seventy-three patients were treated at the German and 134 patients at the Australian trauma centre. DCO was performed in case of increased injury severity in both hospitals. Prolonged mechanical ventilation time, and length of ICU and hospital stay were demonstrated in DCO treatment regardless of the trauma centre. No differences concerning posttraumatic complications and survival were found between both centres. Survival of patients after DCO was similar to those managed using ETC despite a greater severity of injury and lower probability of survival. There was no difference in the incidence of ARDS. DCO was, however, associated with a greatly increased length of time on mechanical ventilation and length of stay in the ICU. We found no differences concerning patient demographics or clinical outcomes in terms of incidence of ARDS, MODS, or mortality. As such, we propose that comparability between German and Australian trauma populations is justified. Despite a higher ISS in the DCO group, there were no differences in posttraumatic complications and survival depending on ETC or DCO treatment. Further research is required to confirm

  12. FUNDAMENTAL TUNNELING PROCESSES IN MOSa SOLAR CELLS

    OpenAIRE

    Balberg , I.; Hanak , J.; Weakliem , H.; Gal , E.

    1981-01-01

    In previous studies of tunneling through a MOSa tunnel junction, where Sa was a-Si : H, it was shown that their characteristics resemble those of MOSc devices where Sc was crystalline silicon. In the present work we would like to report a demonstration of fundamental tunneling processes in such tunnel junctions. In particular, the transition from semiconductor controlled regime to tunneling controlled regime can be clearly distinguished. The present results represent one of the rare cases whe...

  13. Destructive quantum interference in spin tunneling problems

    OpenAIRE

    von Delft, Jan; Henley, Christopher L.

    1992-01-01

    In some spin tunneling problems, there are several different but symmetry-related tunneling paths that connect the same initial and final configurations. The topological phase factors of the corresponding tunneling amplitudes can lead to destructive interference between the different paths, so that the total tunneling amplitude is zero. In the study of tunneling between different ground state configurations of the Kagom\\'{e}-lattice quantum Heisenberg antiferromagnet, this occurs when the spi...

  14. 13th Australian tunnelling conference. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The theme of the conference was 'Engineering in a changing environment'. Topics covered include Australian tunnelling projects, design and development of ground support, tunnelling, international projects, fire and life safety, mining projects, risk management in tunnelling, and tunnel boring machine tunnelling. Papers of particular interest to the coal industry are: improving roadway development in underground coal mine (G. Lewis and G. Gibson), and polymer-based alternative to steel mesh for coal mine strata reinforcement (C. Lukey and others).

  15. Tunnelling instability via perturbation theory

    Energy Technology Data Exchange (ETDEWEB)

    Graffi, S. (Bologna Univ. (Italy). Dip. di Matematica); Grecchi, V. (Moderna Univ. (Italy). Dip. di Matematica); Jona-Lasinio, G. (Paris-11 Univ., 91 - Orsay (France). Lab. de Physique Theorique et Hautes Energies)

    1984-10-21

    The semiclassical limit of low lying states in a multiwell potential is studied by rigorous perturbative techniques. In particular tunnelling instability and localisation of wave functions is obtained in a simple way under small deformations of symmetric potentials.

  16. Scanning Tunneling Microscopy - image interpretation

    International Nuclear Information System (INIS)

    Maca, F.

    1998-01-01

    The basic ideas of image interpretation in Scanning Tunneling Microscopy are presented using simple quantum-mechanical models and supplied with examples of successful application. The importance is stressed of a correct interpretation of this brilliant experimental surface technique

  17. Electron tunneling in proteins program.

    Science.gov (United States)

    Hagras, Muhammad A; Stuchebrukhov, Alexei A

    2016-06-05

    We developed a unique integrated software package (called Electron Tunneling in Proteins Program or ETP) which provides an environment with different capabilities such as tunneling current calculation, semi-empirical quantum mechanical calculation, and molecular modeling simulation for calculation and analysis of electron transfer reactions in proteins. ETP program is developed as a cross-platform client-server program in which all the different calculations are conducted at the server side while only the client terminal displays the resulting calculation outputs in the different supported representations. ETP program is integrated with a set of well-known computational software packages including Gaussian, BALLVIEW, Dowser, pKip, and APBS. In addition, ETP program supports various visualization methods for the tunneling calculation results that assist in a more comprehensive understanding of the tunneling process. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Tunneling Plasmonics in Bilayer Graphene.

    Science.gov (United States)

    Fei, Z; Iwinski, E G; Ni, G X; Zhang, L M; Bao, W; Rodin, A S; Lee, Y; Wagner, M; Liu, M K; Dai, S; Goldflam, M D; Thiemens, M; Keilmann, F; Lau, C N; Castro-Neto, A H; Fogler, M M; Basov, D N

    2015-08-12

    We report experimental signatures of plasmonic effects due to electron tunneling between adjacent graphene layers. At subnanometer separation, such layers can form either a strongly coupled bilayer graphene with a Bernal stacking or a weakly coupled double-layer graphene with a random stacking order. Effects due to interlayer tunneling dominate in the former case but are negligible in the latter. We found through infrared nanoimaging that bilayer graphene supports plasmons with a higher degree of confinement compared to single- and double-layer graphene, a direct consequence of interlayer tunneling. Moreover, we were able to shut off plasmons in bilayer graphene through gating within a wide voltage range. Theoretical modeling indicates that such a plasmon-off region is directly linked to a gapped insulating state of bilayer graphene, yet another implication of interlayer tunneling. Our work uncovers essential plasmonic properties in bilayer graphene and suggests a possibility to achieve novel plasmonic functionalities in graphene few-layers.

  19. Shaft and tunnel sealing considerations

    International Nuclear Information System (INIS)

    Kelsall, P.C.; Shukla, D.K.

    1980-01-01

    Much of the emphasis of previous repository sealing research has been placed on plugging small diameter boreholes. It is increasingly evident that equal emphasis should now be given to shafts and tunnels which constitute more significant pathways between a repository and the biosphere. The paper discusses differences in requirements for sealing shafts and tunnels as compared with boreholes and the implications for seal design. Consideration is given to a design approach for shaft and tunnel seals based on a multiple component design concept, taking into account the requirements for retrievability of the waste. A work plan is developed for the future studies required to advance shaft and tunnel sealing technology to a level comparable with the existing technology for borehole sealing

  20. Organic tunnel field effect transistors

    KAUST Repository

    Tietze, Max Lutz; Lussem, Bjorn; Liu, Shiyi

    2017-01-01

    Various examples are provided for organic tunnel field effect transistors (OTFET), and methods thereof. In one example, an OTFET includes a first intrinsic layer (i-layer) of organic semiconductor material disposed over a gate insulating layer

  1. Bijzondere belastingen in tunnels : Eindrapport

    NARCIS (Netherlands)

    Molenaar, D.J.; Weerheijm, J.; Vervuurt, A.; Burggraaf, H.; Roekaerts, D.; Meijers, P.

    2009-01-01

    Verkeerstunnels en overkapte wegen (landtunnels) komen de milieukundige en stedenbouwkundige inpassing ten goede en maken meervoudig ruimtegebruik in de stad mogelijk. Het aantal tunnels en overkappingen groeit dan ook. Dit maakt het vervoer van explosiegevaarlijke stoffen en onder hoge druk

  2. Free Surface Water Tunnel (FSWT)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The Free Surface Water Tunnel consists of the intake plenum, the test section and the exit plenum. The intake plenum starts with a perforated pipe that...

  3. Subchondral bone density distribution in the human femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Wright, David A.; Meguid, Michael; Lubovsky, Omri; Whyne, Cari M. [Sunnybrook Research Institute, Orthopaedic Biomechanics Laboratory, Toronto, Ontario (Canada)

    2012-06-15

    This study aims to quantitatively characterize the distribution of subchondral bone density across the human femoral head using a computed tomography derived measurement of bone density and a common reference coordinate system. Femoral head surfaces were created bilaterally for 30 patients (14 males, 16 females, mean age 67.2 years) through semi-automatic segmentation of reconstructed CT data and used to map bone density, by shrinking them into the subchondral bone and averaging the greyscale values (linearly related to bone density) within 5 mm of the articular surface. Density maps were then oriented with the center of the head at the origin, the femoral mechanical axis (FMA) aligned with the vertical, and the posterior condylar axis (PCA) aligned with the horizontal. Twelve regions were created by dividing the density maps into three concentric rings at increments of 30 from the horizontal, then splitting into four quadrants along the anterior-posterior and medial-lateral axes. Mean values for each region were compared using repeated measures ANOVA and a Bonferroni post hoc test, and side-to-side correlations were analyzed using a Pearson's correlation. The regions representing the medial side of the femoral head's superior portion were found to have significantly higher densities compared to other regions (p < 0.05). Significant side-to-side correlations were found for all regions (r {sup 2} = 0.81 to r {sup 2} = 0.16), with strong correlations for the highest density regions. Side-to-side differences in measured bone density were seen for two regions in the anterio-lateral portion of the femoral head (p < 0.05). The high correlation found between the left and right sides indicates that this tool may be useful for understanding 'normal' density patterns in hips affected by unilateral pathologies such as avascular necrosis, fracture, developmental dysplasia of the hip, Perthes disease, and slipped capital femoral head epiphysis. (orig.)

  4. Image features of herniation pit of the femoral neck

    International Nuclear Information System (INIS)

    Zhang Xuezhe; Li Guangming; Wang Cunli; Wang Guimin

    2008-01-01

    Objective: To evaluate imaging appearances of herniation pit of the femoral neck. Methods: We retrospectively analyzed the X-ray, CT and MRI findings of 9 patients with herniation pit of the femoral neck. All nine patients were male with the age ranging from 21 to 73 years. They had pain in the hip from two months to two years duration. Results: The bilateral hips were affected in six patients, the right hips in the other 3 patients. Of the nine patients, X-ray plain films (2 cases), CT scanning(6 cases), and MR scanning (5 cases ) were performed. The size of the lesions ranged from 0.5 cm x 0.6 cm to 1.0 cm x 1.5 cm, located in the anterosuperior portion of the femoral neck (n=7) or anteroinferior portion (n=2). X-ray plain films showed an osteolytic lesion surrounded by a sclerotic rim. CT scanning showed the lesion just below the cortex of the femoral neck surrounded by a rim of sclerosis or associated with a small cortical break in two patients. MR scanning showed low signal intensity in five patients on T 1 WI and high signal intensity surrounded by a rim of low signal intensity (n=3) or low signal intensity (n=2) on T 2 WI, and high signal intensity on fat suppression MR image. A small joint effusion was observed in two cases on T 2 WI. Conclusion: The CT and MRI findings of herniation pit of the femoral neck are characteristic, it is useful in defining the diagnosis of the herniation pit of the femoral neck. (authors)

  5. Biophysical stimulation in osteonecrosis of the femoral head

    Directory of Open Access Journals (Sweden)

    Massari Leo

    2009-01-01

    Full Text Available Osteonecrosis of the femoral head is the endpoint of a disease process that results from insufficient blood flow and bone-tissue necrosis, leading to joint instability, collapse of the femoral head, arthritis of the joint, and total hip replacement. Pain is the most frequent clinical symptom. Both bone tissue and cartilage suffer when osteonecrosis of the femoral head develops. Stimulation with pulsed electromagnetic fields (PEMFs has been shown to be useful for enhancing bone repair and for exerting a chondroprotective effect on articular cartilage. Two Italian studies on the treatment of avascular necrosis of the femoral head with PEMFs were presented in this review. In the first study, 68 patients suffering from avascular necrosis of the femoral head were treated with PEMFs in combination with core decompression and autologous bone grafts. The second one is a retrospective analysis of the results of treatment with PEMFs of 76 hips in 66 patients with osteonecrosis of the femoral head. In both studies clinical information and diagnostic imaging were collected at the beginning of the treatment and at the time of follow up. Statistical analysis was performed using chi-square test. Both authors hypothesize that the short-term effect of PEMF stimulation may be to protect the articular cartilage from the catabolic effect of inflammation and subchondral bone-marrow edema. The long-term effect of PEMF stimulation may be to promote osteogenic activity at the necrotic area and prevent trabecular fracture and subchondral bone collapse. PEMF stimulation represents an important therapeutic opportunity to resolve the Ficat stage-I or II disease or at least to delay the time until joint replacement becomes necessary.

  6. Direct, coherent and incoherent intermediate state tunneling and scanning tunnel microscopy (STM)

    International Nuclear Information System (INIS)

    Halbritter, J.

    1997-01-01

    Theory and experiment in tunneling are still qualitative in nature, which hold true also for the latest developments in direct-, resonant-, coherent- and incoherent-tunneling. Those tunnel processes have recently branched out of the field of ''solid state tunnel junctions'' into the fields of scanning tunnel microscopy (STM), single electron tunneling (SET) and semiconducting resonant tunnel structures (RTS). All these fields have promoted the understanding of tunneling in different ways reaching from the effect of coherence, of incoherence and of charging in tunneling, to spin flip or inelastic effects. STM allows not only the accurate measurements of the tunnel current and its voltage dependence but, more importantly, the easy quantification via the (quantum) tunnel channel conductance and the distance dependence. This new degree of freedom entering exponentially the tunnel current allows an unique identification of individual tunnel channels and their quantification. In STM measurements large tunnel currents are observed for large distances d > 1 nm explainable by intermediate state tunneling. Direct tunneling with its reduced tunnel time and reduced off-site Coulomb charging bridges distances below 1 nm, only. The effective charge transfer process with its larger off-site and on-site charging at intermediate states dominates tunnel transfer in STM, biology and chemistry over distances in the nm-range. Intermediates state tunneling becomes variable range hopping conduction for distances larger than d > 2 nm, for larger densities of intermediate states n 1 (ε) and for larger temperatures T or voltages U, still allowing high resolution imaging

  7. Quantum resonances in physical tunneling

    International Nuclear Information System (INIS)

    Nieto, M.M.; Truax, D.R.

    1985-01-01

    It has recently been emphasized that the probability of quantum tunneling is a critical function of the shape of the potential. Applying this observation to physical systems, we point out that in principal information on potential surfaces can be obtained by studying tunneling rates. This is especially true in cases where only spectral data is known, since many potentials yield the same spectrum. 13 refs., 10 figs., 1 tab

  8. Stress fracture of the femoral neck in a child (stress fracture)

    International Nuclear Information System (INIS)

    Coldwell, D.; Gross, G.W.; Boal, D.K.

    1984-01-01

    Femoral neck stress fracture is extremely rare in childhood. We report a case of femoral neck stress fracture in an 11-year-old girl. Differentials diagnosis and a brief review of the literature follow. (orig.)

  9. The treatment of nonisthmal femoral shaft nonunions with im nail exchange versus augmentation plating.

    Science.gov (United States)

    Park, Jin; Kim, Sul Gee; Yoon, Han Kook; Yang, Kyu Hyun

    2010-02-01

    The purpose of this study was to compare the results between exchange nailing (EN) and augmentation plating (AP) with a nail left in situ for nonisthmal femoral shaft nonunion after femoral nailing. : Retrospective data analysis, November 1996-March 2006. A level I trauma center. Eighteen patients with 18 nonisthmal femoral nonunions. Seven patients with 7 fractures treated for nonisthmal femoral shaft nonunions after femoral nailing with EN and 11 patients with 11 fractures treated for nonisthmal femoral shaft nonunions after nailing with AP combined with bone grafting. Union and complications. Five nonunions in the EN group failed to achieve union (72% failure rate), whereas all 11 pseudarthroses in the AP group obtained osseous union. Fisher exact test showed a higher nonunion rate of EN compared with AP for nonisthmal femoral shaft nonunion (odds ratio, 6.5; P = 0.002). AP with autogenous bone grafting may be a better option than EN for nonisthmal femoral nonunions.

  10. Automatic quantification of tibio-femoral contact area and congruity

    DEFF Research Database (Denmark)

    Tummala, Sudhakar; Nielsen, Mads; Lillholm, Martin

    2012-01-01

    We present methods to quantify the medial tibio- femoral (MTF) joint contact area (CA) and congruity index (CI) from low-field magnetic resonance imaging (MRI). Firstly, based on the segmented MTF cartilage compartments, we computed the contact area using the Euclidian distance transformation....... The CA was defined as the area of the tibial superior surface and the femoral inferior surface that are less than a voxel width apart. Furthermore, the CI is computed point-by-point by assessing the first- and second-order general surface features over the contact area. Mathematically, it is the inverse...

  11. Morfología femoral proximal en fracturas de cadera

    OpenAIRE

    Calvo de Mora Rebollo, María Jesús; Albareda Albareda, Jorge Cruz; Seral García, Belén; Martín Ruiz, G.; Lasierra Sanromán, José Manuel; Seral Iñigo, Fernando

    2003-01-01

    Es frecuente observar como pacientes que han sufrido una fractura de cadera, si se fracturan posteriormente la cadera contralateral, es del mismo tipo que la primera fractura. El objetivo de este trabajo es tratar de relacional la morfología femoral proximal con la producción de un tipo determinado de fractura. Para ello hemos realizado un estudio prospectivo en 50 pacientes mayores de 65 años, sin distinción de sexo, que han ingresado en nuestro servicio por fractura femoral proximal, 25 ...

  12. Repair of femoral trochanteric osteotomy in the dog

    International Nuclear Information System (INIS)

    Whitelock, R.G.; Dyce, J.; Houlton, J.E.F.

    1997-01-01

    The records and radiographs of 24 dogs that underwent femoral trochanteric osteotomy repair were reviewed. Osteotomy repair was performed with either a pin and tension band wire or a lag screw technique. Significant clinical complications associated with the osteotomy were identified in one dog (4 per cent) six weeks after surgery, although abnormal radiographic changes were evident in 15 dogs (62 per cent). The method of repair did not influence healing and there were comparable radiographic complication rates. It is concluded that femoral trochanteric osteotomy is not associated with significant clinical problems, despite a high incidence of abnormal radiographic findings

  13. [SURGICAL HIP DISLOCATION APPROACH FOR TREATMENT OF FEMORAL HEAD FRACTURE].

    Science.gov (United States)

    Tang, Yanfeng; Liu, Youwen; Zhu, Yingjie; Li, Jianming; Li, Wuyin; Li, Qiyi; Jia, Yudong

    2015-11-01

    To discuss the value of surgical hip dislocation approach in the treatment of femoral head fracture. A retrospectively analysis was made on the clinical data of 15 patients with femoral head fractures treated through surgical hip dislocation approach between January 2010 and February 2013. There were 11 men and 4 women with an average age of 30.8 years (range, 15-63 years). The causes included traffic accident injury in 9 cases, falling injury from height in 5 cases, and sports injury in 1 case. According to Pipkin typing, 2 cases were rated as type I, 7 cases as type II, 1 case as type III, and 5 cases as type IV. The interval of injury and operation was 2-10 days (mean, 4.1 days). Reduction was performed in 10 patients within 6 hours after injury, and then bone traction was given for 4-6 weeks except 5 patients who received reduction in the other hospital. Primary healing of incision was obtained in all patients after surgery without complications of dislocation and lower limbs deep venous thrombosis. The mean follow-up time was 29.9 months (range, 25-36 months). During follow-up, there was no infection, breakage of internal fixation, or nonunion of femoral greater trochanter fracture. In 3 patients having necrosis of the femoral head, 2 had no obvious symptoms [staging as IIa and IIb respectively according to Association Research Circulation Osseous (ARCO) staging system], and 1 (stage IIIb) had nonunion of the femoral neck fracture, who underwent total hip arthroplasty (THA). In 4 patients having myositis ossificans (2 cases of grade I, 1 case of grade II, and 1 case of grade III based on Brooker grading), no treatment was given in 3 cases and the focus was removed during THA in 1 case. According to the Thompson-Epstein scale at last follow-up, the results were excellent in 9 cases, good in 3 cases, fair in 1 case, and poor in 2 cases, and the excellent and good rate was 80%. Surgical hip dislocation approach can not only protect the residual vessels of the

  14. Medial circumflex femoral artery flap for ischial pressure sore

    Directory of Open Access Journals (Sweden)

    Palanivelu S

    2009-01-01

    Full Text Available A new axial pattern flap based on the terminal branches of the medial circumflex femoral artery is described for coverage of ischial pressure sore. Based on the terminal branches of the transverse branch of medial circumflex femoral artery, which exit through the gap between the quadratus femoris muscle above and the upper border of adductor magnus muscle below, this fascio cutaneous flap is much smaller than the posterior thigh flap but extremely useful to cover ischeal pressure sores. The skin redundancy below the gluteal fold allows a primary closure of the donor defect. It can also be used in combination with biceps femoris muscle flap.

  15. Case of slipped capital femoral epiphysis following radiation

    Energy Technology Data Exchange (ETDEWEB)

    Terada, Hiroshi; Usui, Hiroshi; Nakamura, Yutaka; Chiba, Masahiro; Yamaji, Shushin; Oba, Yoshihiro

    1987-06-01

    A 12-year-old boy presented with pain of the right hip joint and claudication. At the age of 7 months, the patient had received prophylactic irradiation of 30 Gy to the pelvic area including lumbar vertebrae and bilateral hip joints following extirpation of the right undescended testicle for embryonal carcinoma. Roentgenograph showed slipped capial femoral epiphysis. A review of the literature suggests that bone growth and hormonal changes in the early stage of puberty are involved, in addition to radiation damaged epiphyseal cartilage, in the pathophysiologic mechanisms of radiation induced slipped capital femoral epiphysis. (Namekawa, K.).

  16. Can femoral dialysis catheter insertion cause a life threatening complication?

    Directory of Open Access Journals (Sweden)

    Nurkay Katrancıoğlu

    2014-09-01

    Full Text Available Venous catheter (VC insertion may be necessary for the patients with renal failure facing vascular access problem. Femoral VCs are commonly used for their lower complication rates especially in emergency clinics. The incidence of bleeding associated with VC is reported 0.5-1.6%, however, life threatening hemorrhage and complications requiring surgical intervention are very rare. In this manuscript, we aimed to present a case with hemolytic uremic syndrome complicated with retroperitoneal hematoma after femoral VC insertion. J Clin Exp Invest 2014; 5 (3: 472-474

  17. Postoperative hemoglobin level in patients with femoral neck fracture

    OpenAIRE

    Nagra, Navraj; van Popta, Dmitri; Whiteside, Sigrid; Holt, Edward

    2018-01-01

    Objective: The aim of this study was to analyze the changes of hemoglobin levels in patients undergoing fixation for femoral neck fracture.Methods: Peroperative hemoglobin levels of patients who underwent either dynamic hip screw (DHS) fixation (n=74; mean age: 80 years) or hip hemiarthroplasty (n=104; mean age: 84 years) for femoral neck fracture was monitored.Results: There was a statistically and clinically significant mean drop of 31.1 g/L between the preoperative (D0) and postoperative D...

  18. Identification of avascular necrosis in the dysplastic proximal femoral epiphysis

    International Nuclear Information System (INIS)

    Mandell, G.A.; Harcke, H.T.; MacKenzie, W.G.; Bassett, G.S.; Scott, C.I. Jr.; Wills, J.S.

    1989-01-01

    Bilateral radiographic irregularities and deformities of the proximal femoral epiphyses are features of both multiple epiphyseal dysplasia and bilateral idiopathic avascular necrosis. In the past these entities have been difficult to differentiate. This report documents radiographically the occurrence of avascular necrosis in 10 patients with multiple epiphyseal dysplasia by recognizing the superimposition of sclerosis and subchondral fissuring on pre-existing symmetrically irregular proximal femoral ossification centers. Scintigraphic (photopenia) or magnetic resonance (loss of signal) criteria of avascular necrosis confirm its added presence and help to establish an imaging scheme to identify avascular necrosis superimposed on multiple epiphyseal dysplasia. (orig.)

  19. Avascular necrosis associated with nailing of femoral neck fracture

    International Nuclear Information System (INIS)

    Stroemqvist, B.; Hansson, L.I.

    1983-01-01

    Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. SR 85 -scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures. (author)

  20. Identification of avascular necrosis in the dysplastic proximal femoral epiphysis

    Energy Technology Data Exchange (ETDEWEB)

    Mandell, G A; Harcke, H T [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Medical Imaging; MacKenzie, W G; Bassett, G S [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Orthopaedics; Scott, Jr, C I [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Genetics; Wills, J S [Medical Center of Delaware, Newark, DE (USA). Dept. of Radiology

    1989-07-01

    Bilateral radiographic irregularities and deformities of the proximal femoral epiphyses are features of both multiple epiphyseal dysplasia and bilateral idiopathic avascular necrosis. In the past these entities have been difficult to differentiate. This report documents radiographically the occurrence of avascular necrosis in 10 patients with multiple epiphyseal dysplasia by recognizing the superimposition of sclerosis and subchondral fissuring on pre-existing symmetrically irregular proximal femoral ossification centers. Scintigraphic (photopenia) or magnetic resonance (loss of signal) criteria of avascular necrosis confirm its added presence and help to establish an imaging scheme to identify avascular necrosis superimposed on multiple epiphyseal dysplasia. (orig.).

  1. Avascular necrosis associated with nailing of femoral neck fracture

    Energy Technology Data Exchange (ETDEWEB)

    Stroemqvist, B; Hansson, L I [Department of Orthopaedic Surgery, University Hospital in Lund, Sweden

    1983-01-01

    Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. Sr/sup 85/-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures.

  2. Callus features of regenerate fracture cases in femoral lengthening in achondroplasia

    International Nuclear Information System (INIS)

    Devmurari, Kamlesh N.; Song, Hae Ryong; Modi, Hitesh N.; Venkatesh, K.P.; Ju, Kim Seung; Song, Sang Heon

    2010-01-01

    We studied the callus features seen in cases of regenerate fracture in femoral lengthening using a monolateral fixator in achondroplasia to determine whether callus types and shapes can predict the probability of callus fracture. The radiographs of 28 cases of femoral lengthening in 14 patients, 14 cases of callus fracture, and 14 cases without callus fracture were retrospectively analyzed by four observers and classified into different shapes and types in concordance with the Ru Li classification. The average lengthening of 9.4 cm (range 7.5-11.8 cm) was achieved, which was 41% (range 30-55%) of the original length and the average timing of callus fracture was 470 days (range 440-545 days) after surgery in the callus fracture group. While the average lengthening of 9.1 cm (range 8-9.7 cm) was achieved, this was 30% (range 28-32%) of the original length in the group of patients without callus fracture. The callus was atypically shaped, there was a 48% average (range 30-72%) reduction of the callus width compared with the natural width of the femur, and a lucent pathway was present in all cases of regenerate fracture. A lucent pathway was seen in all fracture cases with concave, lateral, and atypical shapes, and there was more than 30% lengthening and 30% reduction of the callus width compared with the natural width of the femur, which are the warning signs for regenerate fractures. These signs help the surgeon to predict the outcome and guide him in planning for any additional interventions. The Ru Li classification is an effective method for the evaluation of the chance of callus fracture. (orig.)

  3. Callus features of regenerate fracture cases in femoral lengthening in achondroplasia

    Energy Technology Data Exchange (ETDEWEB)

    Devmurari, Kamlesh N.; Song, Hae Ryong; Modi, Hitesh N.; Venkatesh, K.P.; Ju, Kim Seung; Song, Sang Heon [Korea University Medical College, Institute for Rare Diseases and Department of Orthopedic Surgery, Seoul (Korea)

    2010-09-15

    We studied the callus features seen in cases of regenerate fracture in femoral lengthening using a monolateral fixator in achondroplasia to determine whether callus types and shapes can predict the probability of callus fracture. The radiographs of 28 cases of femoral lengthening in 14 patients, 14 cases of callus fracture, and 14 cases without callus fracture were retrospectively analyzed by four observers and classified into different shapes and types in concordance with the Ru Li classification. The average lengthening of 9.4 cm (range 7.5-11.8 cm) was achieved, which was 41% (range 30-55%) of the original length and the average timing of callus fracture was 470 days (range 440-545 days) after surgery in the callus fracture group. While the average lengthening of 9.1 cm (range 8-9.7 cm) was achieved, this was 30% (range 28-32%) of the original length in the group of patients without callus fracture. The callus was atypically shaped, there was a 48% average (range 30-72%) reduction of the callus width compared with the natural width of the femur, and a lucent pathway was present in all cases of regenerate fracture. A lucent pathway was seen in all fracture cases with concave, lateral, and atypical shapes, and there was more than 30% lengthening and 30% reduction of the callus width compared with the natural width of the femur, which are the warning signs for regenerate fractures. These signs help the surgeon to predict the outcome and guide him in planning for any additional interventions. The Ru Li classification is an effective method for the evaluation of the chance of callus fracture. (orig.)

  4. The Direct Anterior Approach Does Not Increase Return to Function Following Hemiarthroplasty for Femoral Neck Fracture.

    Science.gov (United States)

    Carlson, Victor R; Ong, Alvin C; Orozco, Fabio R; Lutz, Rex W; Duque, Andres F; Post, Zachary D

    2017-11-01

    The purpose of this study was to evaluate functional outcomes for hemiarthroplasty using a direct anterior approach or a direct lateral approach for femoral neck fracture. This retrospective review used data collected from a single institution between 2006 and 2016. Eighty-five and 75 consecutive patients who underwent hemiarthroplasty via a direct anterior approach and a direct lateral approach, respectively, met inclusion criteria. All patients with femoral neck fractures were treated by 1 of 2 fellowship-trained orthopedic surgeons using the direct anterior approach or the direct lateral approach to hemiarthroplasty. Disposition, ambulation, and other perioperative surgical outcomes were compared between the cohorts. Compared with the direct lateral cohort, the direct anterior cohort had a shorter mean operative time (2.4 minutes, P<.01), a shorter mean length of hospital stay (2.7 days, P<.01), and a smaller mean decrease in hemoglobin postoperatively (0.7 g/dL, P<.01). No significant difference was observed between the cohorts for postoperative disposition, the number of feet ambulated on the second postoperative day, or the prevalence of ambulatory decline at 4- to 6-week and 4- to 6-month follow-up visits. Compared with the direct lateral approach, the direct anterior approach may benefit patients by small, but statistically significant, improvements in blood loss, surgical time, and length of hospital stay after hemiarthroplasty. However, the direct anterior approach does not appear to decrease the likelihood of transfer to a skilled nursing facility postoperatively or accelerate return to preoperative function. [Orthopedics. 2017; 40(6):e1055-e1061.]. Copyright 2017, SLACK Incorporated.

  5. [Ex vivo microCT analysis of possible microfractures of the femoral head during implantation of a cementless hip resurfacing femoral component].

    Science.gov (United States)

    Lerch, M; Olender, G; von der Höh, N; Thorey, F; von Lewinski, G; Meyer-Lindenberg, A; Windhagen, H; Hurschler, C

    2009-01-01

    Microfractures of the femoral head during implantation of the femoral components are suspected to be a cause of fractures at the implant/neck junction which represent a common failure mode in hip resurfacing arthroplasty. Callus formation observed in femoral head retrievals suggests the occurrence of microfractures inside the femoral head, which might be inadvertently caused by the surgeon during implantation. The aim of this biomechanical study was to analyse whether or not the implantation of a cementless femoral component hip resurfacing system causes microfractures in the femoral head. After the preparation of 20 paired human cadaveric femoral heads, the cementless femoral component ESKA Typ BS (ESKA Implants GmbH & Co., Lübeck) was implanted on 9 specimens with an impaction device that generates 4.5 kN impaction force. On 9 specimens the femoral component was implanted by hand. One head was used as a fracture model, 1 specimen served as control without manipulation. The femoral component used for impaction was equipped with hinges to enable its removal without further interfering with the bone stock. Specimens were scanned with a microCT device before and after impaction and the microCT datasets before and after impaction were compared to identify possible microfractures. Twenty strikes per hand or with the impaction device provided sufficient implant seating. Neither the macroscopic examination nor the 2-dimensional microCT analysis revealed any fractures of the femoral heads after impaction. At least macroscopically and in the 2-dimensional microCT analysis, implantation of the cementless hip resurfacing femoral component ESKA Typ BS with 4.5 kN or by hand does not seem to cause fractures of the femoral head. Georg Thieme Verlag KG Stuttgart, New York.

  6. Odd Length Contraction

    Science.gov (United States)

    Smarandache, Florentin

    2013-09-01

    Let's denote by VE the speed of the Earth and byVR the speed of the rocket. Both travel in the same direction on parallel trajectories. We consider the Earth as a moving (at a constant speed VE -VR) spacecraft of almost spherical form, whose radius is r and thus the diameter 2r, and the rocket as standing still. The non-proper length of Earth's diameter, as measured by the astronaut is: L = 2 r√{ 1 -|/VE -VR|2 c2 } rocket! Also, let's assume that the astronaut is laying down in the direction of motion. Therefore, he would also shrink, or he would die!

  7. discouraged by queue length

    Directory of Open Access Journals (Sweden)

    P. R. Parthasarathy

    2001-01-01

    Full Text Available The transient solution is obtained analytically using continued fractions for a state-dependent birth-death queue in which potential customers are discouraged by the queue length. This queueing system is then compared with the well-known infinite server queueing system which has the same steady state solution as the model under consideration, whereas their transient solutions are different. A natural measure of speed of convergence of the mean number in the system to its stationarity is also computed.

  8. Early detection by sup(99m)Tc-Sn-pyrophosphate scintigraphy of femoral head necrosis following medial femoral neck fractures

    International Nuclear Information System (INIS)

    Greiff, J.; Lanng, S.; Hoeilund-Carlsen, P.F.; Karle, A.K.; Uhrenholdt, A.

    1980-01-01

    A selected series of 24 patients with displaced medial femoral neck fracture, treated with closed reduction and osteosynthesis with cancellous bone screws (ASIF), were investigated. During an observation period of 6 to 26 months, serial hip joint scintigraphies were performed and compared with serial X-ray examinations. At the first scintigraphic examination performed on average 5-6 weeks after the fracture, two separate investigators found a decreased amount of activity or no activity in the femoral head of 10 and 8 patients, respectively. At the second scintigraphic examination performed on average 11.1 weeks after the fracture both investigators found no activity or a decreased amount of activity in 8 patients. This figure declined to 7 during the following period, because one patient with decreased activity was recorded as having normal activity 15 months after the fracture. These 7 patients all developed radiological signs of femoral head collapse on average 16.3 months after the fracture (range 5-26 months), whereas their scintigrams displayed decreased or absent tracer uptake on average 1.2 months after the fracture (P<0.01). None of the patients with initially normal or increased uptake later showed decreased or absent uptake during the study and none developed radiological collapse. It may be concluded that absent or decreased uptake of sup(99m)Tc-Sn-pyrophosphate in the femoral head following medial femoral neck fracture indicates femoral head necrosis and a high risk of late segmental collapse, whereas normal or increased uptake implying preserved blood supply means that late segmental collapse will probably never develop. (author)

  9. Fine structures on zero-field steps in low-loss Josephson tunnel junctions

    DEFF Research Database (Denmark)

    Monaco, Roberto; Barbara, Paola; Mygind, Jesper

    1993-01-01

    The first zero-field step in the current-voltage characteristic of intermediate-length, high-quality, low-loss Nb/Al-AlOx/Nb Josephson tunnel junctions has been carefully investigated as a function of temperature. When decreasing the temperature, a number of structures develop in the form...... of regular and slightly hysteretic steps whose voltage position depends on the junction temperature and length. This phenomenon is interesting for the study of nonlinear dynamics and for application of long Josephson tunnel junctions as microwave and millimeter-wavelength oscillators....

  10. Clavicular bone tunnel malposition leads to early failures in coracoclavicular ligament reconstructions.

    Science.gov (United States)

    Cook, Jay B; Shaha, James S; Rowles, Douglas J; Bottoni, Craig R; Shaha, Steven H; Tokish, John M

    2013-01-01

    Modern techniques for the treatment of acromioclavicular (AC) joint dislocations have largely centered on free tendon graft reconstructions. Recent biomechanical studies have demonstrated that an anatomic reconstruction with 2 clavicular bone tunnels more closely matches the properties of native coracoclavicular (CC) ligaments than more traditional techniques. No study has analyzed tunnel position in regard to risk of early failure. To evaluate the effect of clavicular tunnel position in CC ligament reconstruction as a risk of early failure. Case series; Level of evidence, 4. A retrospective review was performed of a consecutive series of CC ligament reconstructions performed with 2 clavicular bone tunnels and a free tendon graft. The population was largely a young, active-duty military group of patients. Radiographs were analyzed for the maintenance of reduction and location of clavicular bone tunnels using a picture archiving and communication system. The distance from the lateral border of the clavicle to the center of each bone tunnel was divided by the total clavicular length to establish a ratio. Medical records were reviewed for operative details and functional outcome. Failure was defined as loss of intraoperative reduction. The overall failure rate was 28.6% (8/28) at an average of 7.4 weeks postoperatively. Comparison of bone tunnel position showed that medialized bone tunnels were a significant predictor for early loss of reduction for the conoid (a ratio of 0.292 vs 0.248; P = .012) and trapezoid bone tunnels (a ratio of 0.171 vs 0.128; P = .004); this correlated to an average of 7 to 9 mm more medial in the reconstructions that failed. Reconstructions performed with a conoid ratio of ≥0.30 were significantly more likely to fail (5/5, 100%) than were those performed lateral to a ratio of 0.30 (3/23, 13.0%) (P < .01). There were no failures when the conoid ratio was <0.25 (0/10, 0%). Conoid tunnel placement was also statistically significant for

  11. Tunnelling without barriers

    International Nuclear Information System (INIS)

    Lee, K.

    1987-01-01

    The evolution in flat and curved space-time of quantum fields in theories with relative flat potential and its consequences are considered. It is shown that bubble nucleation, a quantum mechanical tunnelling process, may occur in flat space-time, having a bounce solution, even if V(phi) has no barrier. It is shown that bubble nucleation can also occur in curved space-time even though there is no bounce solution in the standard formalism for the bubble nucleation rate in curved space-time. Additionally, bubbles can nucleate during the slow rolling period on the potential in flat and curved space-time, in this case also there is no bounce solution. It is known in the new inflationary scenario that energy density perturbations caused by quantum fluctuations of the scalar field can satisfy the presently observed bounds on density perturbations. Bubble nucleation during the slow rolling period also gives rise to density perturbations. For a model potential density perturbations by bubbles are calculated at the horizon reentering. By applying the bound from the almost isotropic microwave black body radiation on these density perturbations, a constraint on the model potential is obtained. Finally, some further implications on the galaxy formation and applications in more realistic potential are discussed

  12. [Treatment of periprosthetic femoral fractures after total hip arthroplasty with specially constructed retrograde hollow nails].

    Science.gov (United States)

    Szalay, G; Meyer, C; Mika, J; Schnettler, R; Thormann, U

    2014-12-01

    Treatment of periprosthetic fractures by implantation of a specially constructed, retrograde hollow nail which fits over the tip of the prosthesis and becomes locked on it. Periprosthetic femoral fractures with firmly anchored prosthesis shaft after total hip arthroplasty of types B1 and C according to the Vancouver classification. Loosened prosthesis (type B2/B3) and trochanteric fractures (type A). Broken or damaged prosthesis, florid inflammation and soft tissue injuries in the operation field, contracted knee joint, advanced deformation in the knee joint and distal femur, enclosed prosthesis and general contraindications. In a supine position the periprosthetic fracture is exposed via a lateral access. For cemented prostheses the cement is removed around the tip of the prosthesis (at least 2-3 cm) and medullary cavity. Arthrotomy with flexion of the knee joint and marking of the nail entry point. Drill the medullary cavity, retrograde introduction of the nail, visually fit the nail over the tip of the prosthesis and lock the nail with the prosthesis. If necessary use additional spongiosaplasty or also placement of additional cerclages depending on fracture type and size of the defect zone. Lock the nail distally. Use intraoperative radiological imaging to control correct positioning and length of the nail. Close the wound layer by layer with placement of suction drainage devices and dressing. Partial loading for 6 weeks with a subsequent pain-adapted loading gradient until full loading is possible. If selective partial loading is not possible, a decision must be made in individual cases as to whether the intraoperative findings allow immediate full loading. From 2004 to 2011 a total of 25 periprosthetic femoral fractures in 25 patients were treated in 2 locations using specially constructed slotted hollow nails. Within the framework of a retrospective study 20 of these patients (16 female and 4 male; average age 77.2 [72-84] years) were clinically and

  13. Evaluation in femoral neck fracture scintimetry: modes of region of interest selection and influence on results

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, S.; Mesko, L.; Stroemqvist, B.; Thorngren, K.G.

    1985-04-01

    Different sized ROIs within the femoral head and different modes of calculation were used in (/sup 99m/Tc)MDP scintimetry after femoral neck fracture. In preoperative scintimetry, correction for increased trochanteric uptake gave the best discrimination, whereas in postoperative scintimetry the direct ratio fractured/intact femoral head was superior. The change in ROI size had little influence.

  14. Evaluation in femoral neck fracture scintimetry: modes of region of interest selection and influence on results

    International Nuclear Information System (INIS)

    Holmberg, S.; Mesko, L.; Stroemqvist, B.; Thorngren, K.G.

    1985-01-01

    Different sized ROIs within the femoral head and different modes of calculation were used in [/sup 99m/Tc]MDP scintimetry after femoral neck fracture. In preoperative scintimetry, correction for increased trochanteric uptake gave the best discrimination, whereas in postoperative scintimetry the direct ratio fractured/intact femoral head was superior. The change in ROI size had little influence

  15. The stability of the femoral component of a minimal invasive total hip replacement system.

    NARCIS (Netherlands)

    Willems, M.M.M.; Kooloos, J.G.M.; Gibbons, P.; Minderhoud, N.; Weernink, T.; Verdonschot, N.J.J.

    2006-01-01

    In this study, the initial stability of the femoral component of a minimal invasive total hip replacement was biomechanically evaluated during simulated normal walking and chair rising. A 20 mm diameter canal was created in the femoral necks of five fresh frozen human cadaver bones and the femoral

  16. 21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metallic cemented or... Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis is a device intended to be implanted...

  17. 21 CFR 888.3400 - Hip joint femoral (hemi-hip) metallic resurfacing prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metallic resurfacing... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3400 Hip joint femoral (hemi-hip) metallic resurfacing prosthesis. (a) Identification. A hip joint femoral (hemi-hip...

  18. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral (hemi-knee...

  19. Estimated carotid-femoral pulse wave velocity has similar predictive value as measured carotid-femoral pulse wave velocity

    DEFF Research Database (Denmark)

    Olsen, Michael; Greve, Sara; Blicher, Marie

    2016-01-01

    OBJECTIVE: Carotid-femoral pulse wave velocity (cfPWV) adds significantly to traditional cardiovascular (CV) risk prediction, but is not widely available. Therefore, it would be helpful if cfPWV could be replaced by an estimated carotid-femoral pulse wave velocity (ePWV) using age and mean blood...... pressure and previously published equations. The aim of this study was to investigate whether ePWV could predict CV events independently of traditional cardiovascular risk factors and/or cfPWV. DESIGN AND METHOD: cfPWV was measured and ePWV calculated in 2366 apparently healthy subjects from four age...

  20. Scanning Tunneling Optical Resonance Microscopy

    Science.gov (United States)

    Bailey, Sheila; Wilt, Dave; Raffaelle, Ryne; Gennett, Tom; Tin, Padetha; Lau, Janice; Castro, Stephanie; Jenkins, Philip; Scheiman, Dave

    2003-01-01

    Scanning tunneling optical resonance microscopy (STORM) is a method, now undergoing development, for measuring optoelectronic properties of materials and devices on the nanoscale by means of a combination of (1) traditional scanning tunneling microscopy (STM) with (2) tunable laser spectroscopy. In STORM, an STM tip probing a semiconductor is illuminated with modulated light at a wavelength in the visible-to-near-infrared range and the resulting photoenhancement of the tunneling current is measured as a function of the illuminating wavelength. The photoenhancement of tunneling current occurs when the laser photon energy is sufficient to excite charge carriers into the conduction band of the semiconductor. Figure 1 schematically depicts a proposed STORM apparatus. The light for illuminating the semiconductor specimen at the STM would be generated by a ring laser that would be tunable across the wavelength range of interest. The laser beam would be chopped by an achromatic liquid-crystal modulator. A polarization-maintaining optical fiber would couple the light to the tip/sample junction of a commercial STM. An STM can be operated in one of two modes: constant height or constant current. A STORM apparatus would be operated in the constant-current mode, in which the height of the tip relative to the specimen would be varied in order to keep the tunneling current constant. In this mode, a feedback control circuit adjusts the voltage applied to a piezoelectric actuator in the STM that adjusts the height of the STM tip to keep the tunneling current constant. The exponential relationship between the tunneling current and tip-to-sample distance makes it relatively easy to implement this mode of operation. The choice of method by which the photoenhanced portion of the tunneling current would be measured depends on choice of the frequency at which the input illumination would be modulated (chopped). If the frequency of modulation were low enough (typically tunneling current

  1. Electronic noise of superconducting tunnel junction detectors

    International Nuclear Information System (INIS)

    Jochum, J.; Kraus, H.; Gutsche, M.; Kemmather, B.; Feilitzsch, F. v.; Moessbauer, R.L.

    1994-01-01

    The optimal signal to noise ratio for detectors based on superconducting tunnel junctions is calculated and compared for the cases of a detector consisting of one single tunnel junction, as well as of series and of parallel connections of such tunnel junctions. The influence of 1 / f noise and its dependence on the dynamical resistance of tunnel junctions is discussed quantitatively. A single tunnel junction yields the minimum equivalent noise charge. Such a tunnel junction exhibits the best signal to noise ratio if the signal charge is independent of detector size. In case, signal charge increases with detector size, a parallel or a series connection of tunnel junctions would provide the optimum signal to noise ratio. The equivalent noise charge and the respective signal to noise ratio are deduced as functions of tunnel junction parameters such as tunneling time, quasiparticle lifetime, etc. (orig.)

  2. Analysis Of Resistance And Effective Wake Friction Due To Addition Of Stern Tunnels On Passenger Ship Using Cfd

    Science.gov (United States)

    Chrismianto, D.; Tuswan; Manik, P.

    2018-03-01

    In this study, the stern tunnel to improve the efficiency of ship propulsion system is analysed. Stern tunnels installed on the two sides of the ship stern. Analysis of ship resistance and wake friction of the ship using CFD are carried out. The stern tunnel height (Hw) and length (L) are implemented to find the better stern tunnel form of the ship. The result of analysis showed that model has a high stern tunnels (Hw) of 1,444 m or additional high stern tunnels ratio of 16% and stern long tunnels (L) about 7 m is a model that has the smallest resistance about 1.1137 N or able to make reduction of resistance amount 11.2582%. While, the model with the addition of height of 0.2 m and a length of 9 m of stern tunnel is a model that has the better advanced speed about 4,927% in increase, and better wake friction about 30.4% in reduce.

  3. Theory of superconducting tunneling without the tunneling Hamiltonian

    International Nuclear Information System (INIS)

    Arnold, G.B.

    1987-01-01

    When a tunneling barrier is nearly transparent, the standard tunneling (or transfer) Hamiltonian approximation fails. The author describes the theory which is necessary for calculating the tunneling current in these cases, and illustrate it by comparing theory and experiment on superconductor/insulator/superconductor (SIS) junctions have ultra-thin tunnel barriers. This theory accurately explains the subgap structure which appears in the dynamical resistance of such SIS junctions, including many observed details which no previous theory has reproduced. The expression for the current through an SIS junction with an ultrathin barrier is given by I(t) = Re{Sigma/sub n/ J/sub n/ (omega/sub o/)e/sup in omega/o/sup t/} where omega/sub o/ = 2eV/h is the Josephson frequency, V is the bias voltage, and the J/sub n/ are voltage dependent coefficients, one for each positive or negative integer, n, and n=0. The relative sign of the terms involving cos(n omega/sub o/t) and sin(n omega/sub o/t) agrees with experiment, in contrast to previous theories of Josephson tunneling

  4. Laboratory Study of the Influence of Substrate Type and Temperature on the Exploratory Tunneling by Formosan Subterranean Termite

    Directory of Open Access Journals (Sweden)

    Bal K. Gautam

    2012-06-01

    Full Text Available Using two-dimensional foraging arenas, laboratory tests were conducted to investigate the effect of soil type, soil moisture level and ambient temperature on the exploratory tunneling by Coptotermes formosanus Shiraki. In choice arenas consisting of two substrate types having two moisture levels each, and conducted at a constant temperature of 22 °C, a significantly greater proportion of termites aggregated in sand than in sandy loam. Similarly, the length of excavated tunnels was also increased in sand. In a given substrate, termite aggregation or tunnel length did not differ between 5% and 15% moisture levels. In no-choice tests, where three different substrates (sand, sandy loam and silt loam were tested at two temperatures (22 °C and 28 °C, excavations were significantly greater in sand than either sandy loam or silt loam at 22 °C. Fewer primary tunnels were constructed in sandy loam than in sand and fewer branched tunnels than either in sand or silt loam. No significant difference in either tunnel length or number of primary or branched tunnels was found between these two temperatures.

  5. A FUNCTIONAL EVALUATION STUDY OF DISTAL FEMORAL FRACTURES FIXED WITH DISTAL FEMORAL LOCKING PLATE

    Directory of Open Access Journals (Sweden)

    Manikumar C. J

    2017-04-01

    Full Text Available BACKGROUND Fractures of the distal femur present considerable challenges in management. Older patients especially women sustain fractures due to osteoporosis. Supracondylar fractures of femur have a bimodal distribution. They account for 6% of all femur fractures and 31% if hip fractures were excluded. Nearly, 50% of distal femur intra-articular fractures are open fractures. Before 1970, most supracondylar fractures were treated nonoperatively; however, difficulties were often encountered including persistent angulatory deformity, knee joint incongruity, loss of knee motion and delayed mobilisation. The trend of open reduction and internal fixation has become evident in recent years with good results being obtained with AO blade plate, dynamic condylar screw, intramedullary supracondylar nail and locking compression plate. Elderly patients and osteoporosis pose difficulty in treating intra-articular fractures of the lower end of femur. Loss of stable fixation is of great concern in these cases. Hence, locking compression plate use has an advantage in these patients. MATERIALS AND METHODS In this study, 20 patients with closed fracture of distal femur were studied. All the cases were treated at the Department of Orthopaedics, Rangaraya Medical College/Government General Hospital, Kakinada, Andhra Pradesh, between November 2013 and November 2015. The method used for fracture fixation was open reduction and internal fixation with distal femoral locking plate. The duration of follow up ranged from 3 months to 24 months. All the fractures in this series were posttraumatic. The patients were functionally evaluated with Neer’s scoring system. 1 RESULTS Twenty distal femoral fractures were treated with distal femoral locking plates. 15 patients were males and 5 patients were females. The median age was 47 years ranging from 28-70 years. 16 of the fractures were caused by road traffic accidents and 2 were due to fall, 2 were due to assault. 12 patients

  6. Injection sealing of the TASS tunnel. Progress report

    International Nuclear Information System (INIS)

    Funehag, Johan

    2008-12-01

    SKB's disposal facility is planned to be located approx. 400-500 m deep and the demands of its water tightness will be very high. The plant will be located in relatively fault-free rock with limited discharge and sealing will be carried out by injection. Given the very fine cracks that need to be sealed and the strong desire to use an injection material which generate a leachate with a pH lower than 11, SKB performs studies of silica sol and cement-based mortar with low pH in order to be able to use these in the sealing works. In the sealing project a 100 m long tunnel is constructed, the TASS tunnel at a depth of 450 min at SKB's rock laboratory on Aespoe. This report includes the results obtained until September 2008. At this date the injection stages 1, 2, and half of stage 3 have been done and preparation for Stage 3 is ongoing. The tunnel has reached a length of 55.5 m and the results from leaching measurements exist for stage 2 (Section 10-34 m). Both cement-based mortar with low pH and silica sol has been used, but cement-based mortar has been used only in relatively small scale. The cement-based mortar is developed especially for the repository. Silica sol used a particle size of about 25 nm and accelerator in the form of sodium chloride. The limit for inward leakage in the tunnel is 1 l/min and 60 m tunnel. Groundwater pressure was found to be 3.0-3.5 MPa. Past results obtained from Stage 2 indicate that injection shields fulfil the rate requirement over a 23 meter distance. The control holes drilled in the screens have been used to gradually steer the injection and to demonstrate a direct sealing effect of the screens. A controllable gelation time is necessary for efficient and controllable injection. Used mixing procedure has been proven to work and intended gelation times have been achieved. The two cement-based mortar mixtures for crack injection used in the project are robust and have desirable properties. Design methodology linking borehole distance

  7. Protein Tunnels: The Case of Urease Accessory Proteins.

    Science.gov (United States)

    Musiani, Francesco; Gioia, Dario; Masetti, Matteo; Falchi, Federico; Cavalli, Andrea; Recanatini, Maurizio; Ciurli, Stefano

    2017-05-09

    Transition metals are both essential micronutrients and limited in environmental availability. The Ni(II)-dependent urease protein, the most efficient enzyme known to date, is a paradigm for studying the strategies that cells use to handle an essential, yet toxic, metal ion. Urease is a virulence factor of several human pathogens, in addition to decreasing the efficiency of soil organic nitrogen fertilization. Ni(II) insertion in the urease active site is performed through the action of three essential accessory proteins: UreD, UreF, and UreG. The crystal structure of the UreD-UreF-UreG complex from the human pathogen Helicobacter pylori (HpUreDFG) revealed the presence of tunnels that cross the entire length of both UreF and UreD, potentially able to deliver Ni(II) ions from UreG to apo-urease. Atomistic molecular dynamics simulations performed on the HpUreDFG complex in explicit solvent and at physiological ionic conditions demonstrate the stability of these protein tunnels in solution and provide insights on the trafficking of water molecules inside the tunnels. The presence of different alternative routes across the identified tunnels for Ni(II) ions, water molecules, and carbonate ions, all involved in urease activation, is highlighted here, and their potential role in the urease activation mechanism is discussed.

  8. Improved multidimensional semiclassical tunneling theory.

    Science.gov (United States)

    Wagner, Albert F

    2013-12-12

    We show that the analytic multidimensional semiclassical tunneling formula of Miller et al. [Miller, W. H.; Hernandez, R.; Handy, N. C.; Jayatilaka, D.; Willets, A. Chem. Phys. Lett. 1990, 172, 62] is qualitatively incorrect for deep tunneling at energies well below the top of the barrier. The origin of this deficiency is that the formula uses an effective barrier weakly related to the true energetics but correctly adjusted to reproduce the harmonic description and anharmonic corrections of the reaction path at the saddle point as determined by second order vibrational perturbation theory. We present an analytic improved semiclassical formula that correctly includes energetic information and allows a qualitatively correct representation of deep tunneling. This is done by constructing a three segment composite Eckart potential that is continuous everywhere in both value and derivative. This composite potential has an analytic barrier penetration integral from which the semiclassical action can be derived and then used to define the semiclassical tunneling probability. The middle segment of the composite potential by itself is superior to the original formula of Miller et al. because it incorporates the asymmetry of the reaction barrier produced by the known reaction exoergicity. Comparison of the semiclassical and exact quantum tunneling probability for the pure Eckart potential suggests a simple threshold multiplicative factor to the improved formula to account for quantum effects very near threshold not represented by semiclassical theory. The deep tunneling limitations of the original formula are echoed in semiclassical high-energy descriptions of bound vibrational states perpendicular to the reaction path at the saddle point. However, typically ab initio energetic information is not available to correct it. The Supporting Information contains a Fortran code, test input, and test output that implements the improved semiclassical tunneling formula.

  9. Five years' experience of transverse groin incision for femoral artery access in arterial reconstructive surgery: parallel observational longitudinal group comparison study.

    LENUS (Irish Health Repository)

    Beirne, Christopher

    2008-07-01

    Vertical groin incisions (VGIs) have been used to access femoral vessels, but reports allude to wound complications. Our aim was to compare VGI with transverse groin incision (TGI) for femoral artery exposure. Over a 5-year interval, 196 patients with 284 femoral artery exposures for supra- and infrainguinal procedures were studied. Primary endpoints were surgical skin site wound infection, seroma, haematoma formation, and major lower limb amputation. Secondary endpoints were graft patency, wound paresthesias, and length of hospital stay. There were 160 TGIs and 124 VGIs. The demographics and risk factor profile were not statistically different between groups. Seroma developed in 4.4% of TGIs and 13.7% of VGIs (p= .005). The complicated skin and soft tissue infection rate was five times greater with VGI (p= .001). The VGI group had a significantly higher rate of major amputation (p= .0005). Significantly higher graft failure rates were observed in the VGI group (p= .011). No paresthesia was reported in any TGI wound. The mean hospital stay was also significantly shorter in the TGI group (p= .006). The study data support and expound on the theory that an alternative incision to VGI offers lower short- and long-term morbidity. Our findings sustain the selection of the TGI in femoral artery surgery for both supra- and infrainguinal procedures without compromise of vessel exposure.

  10. Surgical blood order equation in femoral fracture surgery

    NARCIS (Netherlands)

    Kajja, I.; Bimenya, G. S.; Eindhoven, G. B.; ten Duis, H. Jan; Sibinga, C. T. S.

    Aim: This study aimed at establishing the clinical utility of the surgical blood order equation (SBOE) in patients undergoing femoral fracture surgery. Background: A blood ordering schedule defines the perioperative blood use in elective surgery. It lists the number of units of blood required for

  11. Proximal focal femoral deficiency: evaluation by MR imaging

    International Nuclear Information System (INIS)

    Biko, David M.; Davidson, Richard; Pena, Andres; Jaramillo, Diego

    2012-01-01

    Proximal focal femoral deficiency (PFFD) is a rare congenital anomaly characterized by abnormal development of the proximal femur. The most common radiographic classification (Aitken) does not evaluate the cartilaginous and soft-tissue abnormalities. To demonstrate MR findings of PFFD focusing on features not seen with radiographs. Nine MR examinations of the hip and femurs of seven children with PFFD were retrospectively reviewed. Imaging was quantitatively and qualitatively assessed comparing the affected limb to the contralateral limb and age-matched controls. The children were classified via the Aitken classification. All children had at least mild acetabular dysplasia, and one type D patient had no acetabulum. MR demonstrated that 4/6 children had labral hypertrophy with a decreased distance from the greater trochanter to the acetabular rim, suggesting impingement (P < 0.05). The proximal femoral physis was abnormal in all cases. The connection between the femoral head and shaft if present was fibrous or fibrocartilaginous. MRI can help in evaluation of PFFD by defining the anatomy. MR demonstrates features of the acetabulum and cartilaginous femoral epiphysis and depicts ligamentous abnormalities of the knee. (orig.)

  12. Ender’s Nail fixation in paediatric femoral shaft fractures.

    Directory of Open Access Journals (Sweden)

    Rajeev Dwivedi

    2013-12-01

    Flynn criteria 34 had excellent and 6 had satisfactory results. No poor results were seen. Conclusion: Ender’s nail fixation can be preferred method of treatment for femoral shaft fractures in age group 5 -15 years as the results are excellent and satisfactory. It is technically simple and can be done in a closed manner. It spares the vascularity and growth plate.

  13. MR imaging findings of the femoral marrow in myelodysplastic syndrome

    International Nuclear Information System (INIS)

    Tanaka, Osamu; Takagi, Shojiro; Matsuura, Katsuhiko; Ichikawa, Tamaki; Kobayashi, Yasuyuki; Nagai, Jun

    1995-01-01

    MR imaging of the femoral marrow was performed in 30 patients with myelodysplastic syndrome (MDS), 11 cases of which evolved to acute myeloid leukemia (AML). The MRI appearance was classified into five patterns: fatty marrow; faint signal; nodular pattern; heterogeneous infiltration; and diffuse infiltration. For each type of MDS, MRI patterns of the femoral marrow were evaluated and compared with those in normal subjects as well as in patients with aplastic anemia. Signal intensity alteration, a low signal on T1-weighted SE image and a high signal on STIR image, began in the proximal femoral marrow almost symmetrically in patients with MDS. The area of abnormal signal intensity tended to gradually extend towards the distal portion of the femur as the disease progressed. MRI patterns of the femoral marrow correlated with marrow cellularity, and diffuse marrow infiltration was noted in patients with a more advanced type of MDS or with severe anemia. There were limitations to making an accurate diagnosis of the MDS type on the basis of the MRI pattern. Progression of the MRI appearance in the course of MDS was thought to be a sign suggesting evolution to AML. It was difficult to differentiate hypoplastic MDS from aplastic anemia, although the nodular pattern was commonly seen in the latter disease. (author)

  14. MR imaging findings of the femoral marrow in myelodysplastic syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Osamu; Takagi, Shojiro; Matsuura, Katsuhiko; Ichikawa, Tamaki; Kobayashi, Yasuyuki; Nagai, Jun [Jichi Medical School, Minamikawachi, Tochigi (Japan)

    1995-10-01

    MR imaging of the femoral marrow was performed in 30 patients with myelodysplastic syndrome (MDS), 11 cases of which evolved to acute myeloid leukemia (AML). The MRI appearance was classified into five patterns: fatty marrow; faint signal; nodular pattern; heterogeneous infiltration; and diffuse infiltration. For each type of MDS, MRI patterns of the femoral marrow were evaluated and compared with those in normal subjects as well as in patients with aplastic anemia. Signal intensity alteration, a low signal on T1-weighted SE image and a high signal on STIR image, began in the proximal femoral marrow almost symmetrically in patients with MDS. The area of abnormal signal intensity tended to gradually extend towards the distal portion of the femur as the disease progressed. MRI patterns of the femoral marrow correlated with marrow cellularity, and diffuse marrow infiltration was noted in patients with a more advanced type of MDS or with severe anemia. There were limitations to making an accurate diagnosis of the MDS type on the basis of the MRI pattern. Progression of the MRI appearance in the course of MDS was thought to be a sign suggesting evolution to AML. It was difficult to differentiate hypoplastic MDS from aplastic anemia, although the nodular pattern was commonly seen in the latter disease. (author).

  15. Proximal focal femoral deficiency: evaluation by MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Biko, David M. [National Naval Medical Center, Department of Radiology, Bethesda, MD (United States); Uniformed Services University of Health Sciences, Department of Radiology and Radiological Sciences, Bethesda, MD (United States); Davidson, Richard [The Children' s Hospital of Philadelphia, Department of Orthopedic Surgery, Philadelphia, PA (United States); Pena, Andres; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2012-01-15

    Proximal focal femoral deficiency (PFFD) is a rare congenital anomaly characterized by abnormal development of the proximal femur. The most common radiographic classification (Aitken) does not evaluate the cartilaginous and soft-tissue abnormalities. To demonstrate MR findings of PFFD focusing on features not seen with radiographs. Nine MR examinations of the hip and femurs of seven children with PFFD were retrospectively reviewed. Imaging was quantitatively and qualitatively assessed comparing the affected limb to the contralateral limb and age-matched controls. The children were classified via the Aitken classification. All children had at least mild acetabular dysplasia, and one type D patient had no acetabulum. MR demonstrated that 4/6 children had labral hypertrophy with a decreased distance from the greater trochanter to the acetabular rim, suggesting impingement (P < 0.05). The proximal femoral physis was abnormal in all cases. The connection between the femoral head and shaft if present was fibrous or fibrocartilaginous. MRI can help in evaluation of PFFD by defining the anatomy. MR demonstrates features of the acetabulum and cartilaginous femoral epiphysis and depicts ligamentous abnormalities of the knee. (orig.)

  16. Isolated femoral hypoplasia: an intrauterine differential diagnosis to campomelia

    Energy Technology Data Exchange (ETDEWEB)

    Koerber, Friederike; Benz-Bohm, Gabriele [University of Cologne, Department of Paediatric Radiology, Cologne (Germany); Schoenau, Eckard [University of Cologne, Department of Paediatrics, Cologne (Germany); Horwitz, A.Eldad [Klinikum Krefeld, Department of Paediatric Radiology, Krefeld (Germany)

    2005-06-01

    The isolated form of femoral bowing is an important differential diagnosis of campomelia. Therefore, knowledge of isolated anomalies is fundamental for prenatal diagnosis, especially for the differential diagnosis from severe syndromes. Four cases are presented to discuss the differential diagnosis of femoral bowing including a review of the literature. We report four newborn babies with unilateral bowing and shortening of the femur. Three had no further anomaly; one child had additional abnormalities due to coumarin embryopathy. The radiological findings were shortened femora with bowing and varus deformity and cortical thickening on the concave side. All other parts showed normal bone structure. The aetiology of femoral bowing is unknown. Early damage of the cartilaginous model followed by remodelling with thickening on the concave side of the bone similar to the healing of malaligned fractures is suspected. The isolated form of femoral bowing without any other anomalies has to be differentiated from complex and more often severe congenital syndromes such as campomelia. Postpartum radiological examination should be reduced to a single exposure of the affected limb and follow-up should be done by clinical examination. (orig.)

  17. Management of a femoral fracture complicated by clostridial myositis

    International Nuclear Information System (INIS)

    Thomson, M.J.; Eger, C.E.

    1997-01-01

    A clinical case of clostridial myositis secondary to a comminuted femoral fracture is described. This case is unusual because, despite the severe degree of obvious muscle necrosis and gas production, the dog had minimal signs of systemic toxicity. Union of the fracture was achieved but six months postoperatively muscular contracture had resulted in permanent stifle extension

  18. Incidental finding of hypertension and diminished femoral pulses ...

    African Journals Online (AJOL)

    2012-06-08

    Jun 8, 2012 ... Case Study: Incidental finding of hypertension and diminished femoral pulses. 168. Vol 55 No 2. S Afr Fam Pract 2013. Introduction. Coarctation of the aorta is ... Surgery of the aorta and its branches. Philadelphia: WB Saunders Company, 2000; p. 3-10. 2. Rao PS. Coarctation of the aorta. Curr Cardiol Rep.

  19. Treatment of femoral neck fracture by Moore Prosthesis in Cotonou ...

    African Journals Online (AJOL)

    Treatment of femoral neck fracture by Moore Prosthesis in Cotonou. AHM Akue, M Lawson, S Madougou, R Zannou, J Padonou. Abstract. Keywords: Benin; hip; Moore prosthesis; results. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  20. Early micromovement of the Articular Surface Replacement (ASR) femoral component

    DEFF Research Database (Denmark)

    Penny, J O; Ding, M; Varmarken, J E

    2012-01-01

    Radiostereometric analysis (RSA) can detect early micromovement in unstable implant designs which are likely subsequently to have a high failure rate. In 2010, the Articular Surface Replacement (ASR) was withdrawn because of a high failure rate. In 19 ASR femoral components, the mean micromovement...

  1. Blood flow and microdialysis in the human femoral head

    DEFF Research Database (Denmark)

    Bøgehøj, Morten; Emmeluth, Claus; Overgaard, Søren

    2007-01-01

    BACKGROUND: If it would be possible to detect lack of flow and/or the development of ischemia in bone, we might have a way of predicting whether a broken bone will heal. We established microdialysis (MD) and laser Doppler (LD) flow measurement in the human femoral head in order to be able to detect...

  2. Retained portion of latex glove during femoral nailing. Case report.

    Science.gov (United States)

    Sadat-Ali, M; Marwah, S; al-Habdan, I

    1996-11-01

    A case of retained glove during Kuntscher intramedullary nailing is described. An abscess around the glove could have lead to osteomyelitis. One need to be cautious feeling the top end of the nail while femoral nailing to avoid such a complication.

  3. Radionuclide scintimetry for diagnosis of complications following femoral neck fracture

    International Nuclear Information System (INIS)

    Alberts, K.A.; Dahlborn, M.; Hindmarsh, J.; Soederborg, B.; Ringertz, H.

    1984-01-01

    A scintimetric study using Tc-99m MDP was made of 54 patients with delayed union, nonunion, or late segmental collapse of the femoral head, 4-92 months after femoral neck fracture. In radiographically verified collapse, the radionuclide uptake ratio between the femoral head on the fractured and on the intact side (HHR) was significantly higher than in fractures resulting in delayed union or nonunion. On the basis of scintimetric and radiographic findings, the patients with healing disturbances could be divided into three groups, characterized by the following features: (1) Satisfactory post-reduction position of the fracture without subsequent redisplacement and a high HHR, which as a rule turned out to be delayed union; (2) The same radiographic pattern but with a lower HHR, which in most cases resulted in nonunion; (3) Inadequate reduction or early redisplacement of the fracture with a high HHR, which resulted in nonunion. The fractional precision in discriminating between different types of disturbed fracture healing by means of skeletal scintimetry was 0.86 in this study. This non-invasive and technically simple method would therefore be a valuable complement to radiography in the assessment of healing, more than 4 months after fracture of the femoral neck. (author)

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

    NARCIS (Netherlands)

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

    1988-01-01

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

  5. Scaling in Theropod Dinosaurs: Femoral Bone Strength and Locomotion II

    Science.gov (United States)

    Lee, Scott

    2015-01-01

    In the second paper of this series, the effect of transverse femoral stresses due to locomotion in theropod dinosaurs of different sizes was examined for the case of an unchanging leg geometry. Students are invariably thrilled to learn about theropod dinosaurs, and this activity applies the concepts of torque and stress to the issue of theropod…

  6. fibular osteosynthesis of neglected femoral neck fracture in a young

    African Journals Online (AJOL)

    As soon as a diagnosis of non-displaced fracture of his right hip was made he discharged himself ... in dogs that cortical grafts provided structural support to the necrotic femoral head preventing its collapse ... possibility of future osteoarthritis of the index hip and the need for regular follow-up. In conclusion, the use of ...

  7. Femoral head injuries: Which treatment strategy can be recommended?

    NARCIS (Netherlands)

    Henle, Philipp; Kloen, Peter; Siebenrock, Klaus A.

    2007-01-01

    Despite different operative and non-operative treatment regimens, the outcome after femoral head fractures has changed little over the past decades. The initial trauma itself as well as secondary changes such as posttraumatic osteoarthritis, avascular necrosis or heterotopic ossification is often

  8. Bone scintigraphy in idiopathic aseptic femoral head necrosis (IAFHN)

    Energy Technology Data Exchange (ETDEWEB)

    Dodig, D; Ugarkovic, B; Orlic, D

    1983-01-01

    Idiopathic aseptic femoral head necrosis (IAFHN) is a disease of unknown aetiology most commonly affecting adults, producing functional impairment of the hip joint and immobility. Characteristic macroscopic, microscopic and radiologic features include: (1) changes in joint cartilage, (2) subchondral necrotic area, (3) changes in fibrous tissue, and (4) osteosclerosis and vascular proliferation. The diagnosis is based on clinical and X-ray examinations. More recently scintigraphy has been used in diagnosing IAFHN. It is a very sensitive, but non-specific method. Nineteen patients aged 25-57 years were included in our study. Scintigrams were divided in four groups: (1) normal, (2) uniformly increased activity in the femoral head, (3) non-uniformly increased activity in the femoral head, and (4) a photon deficient area in the femoral head. A comparison of scintigraphy and radiological examination suggests that a photon deficient area corresponds with stage III of radiological classification, non-uniformly increased activity with stage II, and uniformly increased activity with stage I. These results indicate that scintigraphy can be used for staging of disease.

  9. Adductor Canal Block versus Femoral Nerve Block and Quadriceps Strength

    DEFF Research Database (Denmark)

    Jæger, Pia Therese; Nielsen, Zbigniew Jerzy Koscielniak; Henningsen, Lene Marianne

    2013-01-01

    : The authors hypothesized that the adductor canal block (ACB), a predominant sensory blockade, reduces quadriceps strength compared with placebo (primary endpoint, area under the curve, 0.5-6 h), but less than the femoral nerve block (FNB; secondary endpoint). Other secondary endpoints were...

  10. Mechanical properties of femoral trabecular bone in dogs

    Directory of Open Access Journals (Sweden)

    Nolte Ingo

    2005-03-01

    Full Text Available Abstract Background Studying mechanical properties of canine trabecular bone is important for a better understanding of fracture mechanics or bone disorders and is also needed for numerical simulation of canine femora. No detailed data about elastic moduli and degrees of anisotropy of canine femoral trabecular bone has been published so far, hence the purpose of this study was to measure the elastic modulus of trabecular bone in canine femoral heads by ultrasound testing and to assess whether assuming isotropy of the cancellous bone in femoral heads in dogs is a valid simplification. Methods From 8 euthanized dogs, both femora were obtained and cubic specimens were cut from the centre of the femoral head which were oriented along the main pressure and tension trajectories. The specimens were tested using a 100 MHz ultrasound transducer in all three orthogonal directions. The directional elastic moduli of trabecular bone tissue and degrees of anisotropy were calculated. Results The elastic modulus along principal bone trajectories was found to be 11.2 GPa ± 0.4, 10.5 ± 2.1 GPa and 10.5 ± 1.8 GPa, respectively. The mean density of the specimens was 1.40 ± 0.09 g/cm3. The degrees of anisotropy revealed a significant inverse relationship with specimen densities. No significant differences were found between the elastic moduli in x, y and z directions, suggesting an effective isotropy of trabecular bone tissue in canine femoral heads. Discussion This study presents detailed data about elastic moduli of trabecular bone tissue obtained from canine femoral heads. Limitations of the study are the relatively small number of animals investigated and the measurement of whole specimen densities instead of trabecular bone densities which might lead to an underestimation of Young's moduli. Publications on elastic moduli of trabecular bone tissue present results that are similar to our data. Conclusion This study provides data about directional elastic

  11. Technique and results of femoral bifurcation endarterectomy by eversion.

    Science.gov (United States)

    Dufranc, Julie; Palcau, Laura; Heyndrickx, Maxime; Gouicem, Djelloul; Coffin, Olivier; Felisaz, Aurélien; Berger, Ludovic

    2015-03-01

    This study evaluated, in a contemporary prospective series, the safety and efficacy of femoral endarterectomy using the eversion technique and compared our results with results obtained in the literature for the standard endarterectomy with patch closure. Between 2010 and 2012, 121 patients (76% male; mean age, 68.7 years; diabetes, 28%; renal insufficiency, 20%) underwent 147 consecutive femoral bifurcation endarterectomies using the eversion technique, associating or not inflow or outflow concomitant revascularization. The indications were claudication in 89 procedures (60%) and critical limb ischemia in 58 (40%). Primary, primary assisted, and secondary patency of the femoral bifurcation, clinical improvement, limb salvage, and survival were assessed using Kaplan-Meier life-table analysis. Factors associated with those primary end-points were evaluated with univariate analysis. The technical success of eversion was of 93.2%. The 30-day mortality was 0%, and the complication rate was 8.2%; of which, half were local and benign. Median follow-up was 16 months (range, 1.6-31.2 months). Primary, primary assisted, and secondary patencies were, respectively, 93.2%, 97.2%, and 98.6% at 2 years. Primary, primary assisted, and secondary maintenance of clinical improvement were, respectively, 79.9%, 94.6%, and 98.6% at 2 years. The predictive factors for clinical degradation were clinical stage (Rutherford category 5 or 6, P = .024), platelet aggregation inhibitor treatment other than clopidogrel (P = .005), malnutrition (P = .025), and bad tibial runoff (P = .0016). A reintervention was necessary in 18.3% of limbs at 2 years: 2% involving femoral bifurcation, 6.1% inflow improvement, and 9.5% outflow improvement. The risk factors of reintervention were platelet aggregation inhibitor (other than clopidogrel, P = .049) and cancer (P = .011). Limb preservation at 2 years was 100% in the claudicant population. Limb salvage was 88.6% in the critical limb ischemia population

  12. Superconducting tunneling with the tunneling Hamiltonian. II. Subgap harmonic structure

    International Nuclear Information System (INIS)

    Arnold, G.B.

    1987-01-01

    The theory of superconducting tunneling without the tunneling Hamiltonian is extended to treat superconductor/insulator/superconductor junctions in which the transmission coefficient of the insulating barrier approaches unity. The solution for the current in such junctions is obtained by solving the problem of a particle hopping in a one-dimensional lattice of sites, with forward and reverse transfer integrals that depend on the site. The results are applied to the problem of subgap harmonic structure in superconducting tunneling. The time-dependent current at finite voltage through a junction exhibiting subgap structure is found to have terms that oscillate at all integer multiples of the Josephson frequency, n(2eV/h). The amplitudes of these new, and as yet unmeasured, ac current contributions as a function of voltage are predicted

  13. Study of the anatomical position of the femoral nerve by magnetic resonance imaging in patients with fractured neck of femur: relevance to femoral nerve block.

    LENUS (Irish Health Repository)

    Mehmood, Shehzad

    2012-01-31

    STUDY OBJECTIVE: To determine the anatomical location of the femoral nerve in patients who have sustained fracture of the neck of femur, and its relevance to femoral nerve block technique. DESIGN: Prospective, observational clinical study. SETTING: Orthopedic and Radiology departments of a regional hospital. SUBJECTS: 10 consecutive adult ASA physical status II and III patients (mean age, 78.5 yrs) and 4 adult healthy volunteers. INTERVENTIONS: A T1 magnetic resonance imaging scan was performed of both upper thighs in patients and healthy volunteers successfully. MEASUREMENTS: The distance (mm) between the midpoint of the femoral artery and the midpoint of the femoral nerve, and the distance of the femoral nerve from the skin was measured at the mid-inguinal ligament, the pubic tubercle, and at the mid-inguinal crease. Data are shown as means (SD). Differences between both sides were compared using paired Student\\'s t-tests. P < 0.05 was significant. MAIN RESULTS: In patients the mean distance (mm) between the midpoint of the femoral nerve from the midpoint of femoral artery at the mid-inguinal crease on the fractured and non-fractured sides was 10.7 and 11.0, respectively (P = 0.87). The mean distance (mm) between the midpoint of the femoral nerve from the midpoint of the femoral artery at the mid-inguinal ligament on the fractured and non-fractured sides was 9.64 and 12.5, respectively (P = 0.03). The mean distance (mm) between the midpoint of the femoral nerve from the midpoint of the femoral artery at the pubic tubercle on the fractured and non-fractured sides was 8.74 and 10.49, respectively (P = 0.18). CONCLUSIONS: Blockade of the femoral nerve may be easier to perform at the mid-inguinal crease in patients with fractured neck of femur.

  14. Typical Underwater Tunnels in the Mainland of China and Related Tunneling Technologies

    Directory of Open Access Journals (Sweden)

    Kairong Hong

    2017-12-01

    Full Text Available In the past decades, many underwater tunnels have been constructed in the mainland of China, and great progress has been made in related tunneling technologies. This paper presents the history and state of the art of underwater tunnels in the mainland of China in terms of shield-bored tunnels, drill-and-blast tunnels, and immersed tunnels. Typical underwater tunnels of these types in the mainland of China are described, along with innovative technologies regarding comprehensive geological prediction, grouting-based consolidation, the design and construction of large cross-sectional tunnels with shallow cover in weak strata, cutting tool replacement under limited drainage and reduced pressure conditions, the detection and treatment of boulders, the construction of underwater tunnels in areas with high seismic intensity, and the treatment of serious sedimentation in a foundation channel of immersed tunnels. Some suggestions are made regarding the three potential great strait-crossing tunnels—the Qiongzhou Strait-Crossing Tunnel, Bohai Strait-Crossing Tunnel, and Taiwan Strait-Crossing Tunnel—and issues related to these great strait-crossing tunnels that need further study are proposed. Keywords: Underwater tunnel, Strait-crossing tunnel, Shield-bored tunnel, Immersed tunnel, Drill and blast

  15. Mortality Following Periprosthetic Proximal Femoral Fractures Versus Native Hip Fractures.

    Science.gov (United States)

    Boylan, Matthew R; Riesgo, Aldo M; Paulino, Carl B; Slover, James D; Zuckerman, Joseph D; Egol, Kenneth A

    2018-04-04

    The number of periprosthetic proximal femoral fractures is expected to increase with the increasing prevalence of hip arthroplasties. While native hip fractures have a well-known association with mortality, there are currently limited data on this outcome among the subset of patients with periprosthetic proximal femoral fractures. Using the New York Statewide Planning and Research Cooperative System, we identified patients from 60 to 99 years old who were admitted to a hospital in the state with a periprosthetic proximal femoral fracture (n = 1,655) or a native hip (femoral neck or intertrochanteric) fracture (n = 97,231) between 2006 and 2014. Within the periprosthetic fracture cohort, the indication for the existing implant was not available in the data set. We used mixed-effects regression models to compare mortality at 1 and 6 months and 1 year for periprosthetic compared with native hip fractures. The risk of mortality for patients who sustained a periprosthetic proximal femoral fracture was no different from that for patients who sustained a native hip fracture at 1 month after injury (3.2% versus 4.6%; odds ratio [OR], 0.90; 95% confidence interval [CI], 0.68 to 1.19; p = 0.446), but was lower at 6 months (3.8% versus 6.5%; OR, 0.74; 95% CI, 0.57 to 0.95; p = 0.020) and 1 year (9.7% versus 15.9%; OR, 0.71; 95% CI, 0.60 to 0.85; p accounting for age and comorbidities. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

  16. Morphometric findings in avascular necrosis of the femoral head.

    Science.gov (United States)

    Kamal, Diana; Trăistaru, Rodica; Alexandru, D O; Kamal, C K; Pirici, D; Pop, O T; Mălăescu, D Gh

    2012-01-01

    Avascular necrosis of the femoral head is an illness with a controversial etiology, the trigger event being the suppression of blood flow to the femoral head. The disease affects mostly young adults within their third and fifth decade, the majority of the patients being men. The main risk factors are trauma, chronic alcohol consumption, smoking, corticotherapy. The main goal of our study is to describe the morphometric changes found in the bone tissue of patients diagnosed with avascular necrosis of the femoral head, with different risk factors, by comparing the area of bone trabeculae inside the area of necrosis with that from the adjacent viable tissue. The morphometric study used biological material from 16 patients with ages between 29 and 57 years, who underwent surgery for avascular necrosis of the femoral head. They were admitted in the Orthopedics Department at the Emergency County Hospital in Craiova between 2010 and 2011 and were split into four groups. Group I presented trauma as the main risk factor, Group II had corticotherapy as the defining risk factor, Group III presented chronic alcohol consumption and Group IV was represented by the patients who smoked and exhibited chronic alcohol consumption. There was not a significant statistical difference between the areas of bone trabeculae of the four groups when we compared viable bone tissue to the necrotized one. Knowing the risk factors of the avascular necrosis of the femoral head is critical to the management of the disease, because diagnosing it in an early stage is a necessity for obtaining a good result for conservative treatment.

  17. Current noise in tunnel junctions

    Energy Technology Data Exchange (ETDEWEB)

    Frey, Moritz; Grabert, Hermann [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Strasse 3, 79104, Freiburg (Germany)

    2017-06-15

    We study current fluctuations in tunnel junctions driven by a voltage source. The voltage is applied to the tunneling element via an impedance providing an electromagnetic environment of the junction. We use circuit theory to relate the fluctuations of the current flowing in the leads of the junction with the voltage fluctuations generated by the environmental impedance and the fluctuations of the tunneling current. The spectrum of current fluctuations is found to consist of three parts: a term arising from the environmental Johnson-Nyquist noise, a term due to the shot noise of the tunneling current and a third term describing the cross-correlation between these two noise sources. Our phenomenological theory reproduces previous results based on the Hamiltonian model for the dynamical Coulomb blockade and provides a simple understanding of the current fluctuation spectrum in terms of circuit theory and properties of the average current. Specific results are given for a tunnel junction driven through a resonator. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Superconducting tunnel-junction refrigerator

    International Nuclear Information System (INIS)

    Melton, R.G.; Paterson, J.L.; Kaplan, S.B.

    1980-01-01

    The dc current through an S 1 -S 2 tunnel junction, with Δ 2 greater than Δ 1 , when biased with eV 1 +Δ 2 , will lower the energy in S 1 . This energy reduction will be shared by the phonons and electrons. This device is shown to be analogous to a thermoelectric refrigerator with an effective Peltier coefficient π* approx. Δ 1 /e. Tunneling calculations yield the cooling power P/sub c/, the electrical power P/sub e/ supplied by the bias supply, and the cooling efficiency eta=P/sub c//P/sub e/. The maximum cooling power is obtained for eV= +- (Δ 2 -Δ 1 ) and t 1 =T 1 /T/sub c/1 approx. 0.9. Estimates are made of the temperature difference T 2 -T 1 achievable in Al-Pb and Sn-Pb junctions with an Al 2 O 3 tunneling barrier. The performance of this device is shown to yield a maximum cooling efficiency eta approx. = Δ 1 /(Δ 2 -Δ 1 ) which can be compared with that available in an ideal Carnot refrigerator of eta=T 1 /(T 2 -T 1 ). The development of a useful tunnel-junction refrigerator requires a tunneling barrier with an effective thermal conductance per unit area several orders of magnitude less than that provided by the A1 2 O 3 barrier in the Al-Pb and Sn-Pb systems

  19. TunnelVision: LHC Tunnel Photogrammetry System for Structural Monitoring

    CERN Document Server

    Fallas, William

    2014-01-01

    In this document an algorithm to detect deformations in the LHC Tunnel of CERN is presented. It is based on two images, one represents the ideal state of the tunnel and the other one the actual state. To find the differences between both, the algorithm is divided in three steps. First, an image enhancement is applied to make easier the detection. Second, two different approaches to reduce noise are applied to one or both images. And third, it is defined a group of characteristics about the type of deformation desired to detect. Finally, the conclusions show the effectiveness of the algorithm in the experimental results.

  20. Geochemical study of acid mine drainage of the Big Lick Tunnel area, Williamstown, PA

    International Nuclear Information System (INIS)

    Tollin, S.

    1993-01-01

    Acid mine drainage in the anthracite region of Pennsylvania continues to be a significant environmental problem. This study examines the acid mine outflow from the Big Lick Tunnel, north of Williamstown, Dauphin County, Pennsylvania. The tunnel drains abandoned mines on the north side of the Big Lick Mountain. Mining ceased in the area circa 1940, and the tunnel has been in operation since that time. The water, soil and stream bed sediment geochemistry has been studied to determine their changes in chemistry over distance. The pH, TDS and metal concentrations were the primary focus. Metal concentrations were determined using an ICP unit. Data indicates the pH of the outflow to range between 6.7 and 7.3 Fe and Mn concentrations are as high as 9.7 ppb. Extensive metal precipitation (''yellow boy'') occurs within the tunnel and for several hundred meters from the mouth of the tunnel. The combination of near neutral pH and high metal concentration suggest that the drainage is in contact with highly alkaline materials prior to discharge from the tunnel. The geology of the area does not suggest bedrock as the possible source of alkaline material. One hypothesis is that the acidic water is reacting with the concrete tunnel and being neutralized. Data also suggests that the Fe precipitates much quicker than the Mn, resulting in a zonation between Fe-rich and Mn-rich sediments along the length of the drainage