Line Traction Research Articles

S1077 Novel Through the Scope Steerable Grasper Reduces Dissection Time and Technical Demand in Endoscopic Submucosal Dissection in Novice Endoscopists Compared to Clip and Line Traction Method: An Ex Vivo Randomized Study

Introduction: Lack of effective devices to aid in tissue traction to facilitate endoscopic submucosal dissection (ESD) leads to prolonged dissection time. Clip and line (CL) method is commonly used to provide traction and improve visualization of the submucosa. A novel through the scope dynamic steerable grasping arm (SGA) has recently been available. We aim to prospectively study the efficacy of this new device with novice endoscopists in an ex vivo setting. Methods: This is a prospective single center randomized trial. In an ex-vivo porcine stomach model, two 25mm circular lesions were marked. Submucosal injection using a lifting agent and circumferential incision was performed. Novice endoscopists with no prior experience of ESD and with one to three years of experience of performing endoscopies were randomized to either SGA (study group) or CL method (control group) first. Each endoscopists performed ESD with both methods. Primary outcome was total dissection time in minutes. Adverse events of muscle injury, perforation, mucosal injury or tissue fragmentation were noted. Participants were asked to choose their preferred traction method for future ESDs. Subsequently, NASA task load index was used to grade subjective mental and physical work load. Results: Ten subjects participated in the study and five were randomized to SGA method first. The mean dissection time was significantly shorter when using SGA compared to clip and line method (5.07 ± 2.19 mins vs 20.07 ± 8.45 mins, P< 0.001) irrespective of order of randomization. Four instances of muscle injury and one perforation were noted with CL and none with SGA. NASA task load index scores across the domains of mental demand (7.9 ± 3.1 vs 15 ± 4 , P< 0.001), physical demand (6.4 ± 2.5 vs 12.9 ± 5.6, P=0.009), temporal demand (5.6 ± 3.3 vs 13.8 ± 4.3, P< 0.001), performance (3.9 ± 3.2 vs 9.2 ± 5.0, P=0.02), effort (8.4 ± 3.5 vs 16.3 ± 2.8, P< 0.001) and frustration (3.9 ± 2.3 vs 14.3 ± 5.1, P< 0.001) were significantly lower with SGA compared to CL. All participants preferred SGA over CL method. Conclusion: With novice endoscopists performing ESD, SGA leads to faster dissection time compared to CL for traction with a reduced mental and physical work load. There was a trend towards reduced adverse events with SGA. SGA is a promising tool to improve efficiency and learning curve of ESD (Table). Table 1. - Dissection times between two methods across the two randomized groups Randomization Number of subjects Dissection time in minutes using SGA (mean +/- SD) Dissection time in minutes using CL (mean +/- SD) P value SGA first 5 5.32 + 2.21 22.6 + 11.42 0.017 CL first 5 4.82 + 2.41 17.5 + 3.70 0.002 Total 10 5.07 + 2.19 20.07 + 8.45 < 0.001 SGA: Steerable grasping arm; CL: Clip and line.

S1153 Gaining Traction: A Novel Through-the-Scope Steerable Grasping Arm vs Clip Line Traction for Gastric and Rectosigmoid ESD

S1153 Gaining Traction: A Novel Through-the-Scope Steerable Grasping Arm vs Clip Line Traction for Gastric and Rectosigmoid ESD

How to Perform a High-Quality Endoscopic Submucosal Dissection

How to Perform a High-Quality Endoscopic Submucosal Dissection

Pocket‐creation method with pulley clip elastic line traction for large rectal tumors

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Efficacy of Current Traction Techniques for Endoscopic Submucosal Dissection.

This systematic review aimed to assess the efficacy of the current approach to tissue traction during the endoscopic submucosal dissection (ESD) of superficial esophageal cancer, early gastric cancer, and colorectal neoplasms. We performed a systematic electronic literature search of articles published in PubMed and selected comparative studies to investigate the treatment outcomes of traction-assisted versus conventional ESD. Using the keywords, we retrieved 381 articles, including five eligible articles on the esophagus, 13 on the stomach, and 12 on the colorectum. A total of seven randomized controlled trials and 23 retrospective studies were identified. Clip line traction and submucosal tunneling were effective in reducing the procedural time during esophageal ESD. The efficacy of traction methods in gastric ESD varied in terms of the devices and strategies used depending on the lesion location and degree of submucosal fibrosis. Several prospective and retrospective studies utilized traction devices without the need to reinsert the colonoscope. When pocket creation is included, the traction devices and methods effectively shorten the procedural time during colorectal ESD. Although the efficacy is dependent on the organ and tumor locations, several traction techniques have been demonstrated to be efficacious in facilitating ESD by maintaining satisfactory traction during dissection.

A challenging case of gastric endoscopic submucosal dissection: removal of a sizable cancer through altering patient's position and multiple clip-line traction.

A challenging case of gastric endoscopic submucosal dissection: removal of a sizable cancer through altering patient's position and multiple clip-line traction.

Insulated tip knife tunneling technique with clip line traction for safe endoscopic submucosal dissection of large circumferential esophageal cancer.

Insulated tip knife tunneling technique with clip line traction for safe endoscopic submucosal dissection of large circumferential esophageal cancer.

Algorithm implementation of traction converter topology based on MFT and single phase matrix converter

This paper presents an implementation of control algorithms of traction converter topology with medium frequency transformer (MFT) using matrix converters intended for locomotives and particularly for suburban units supplied by a 25 kV/50 Hz and/or 15 kV/16.7 Hz AC overhead line. Traction converter consists of input medium voltage matrix converters directly connected to the overhead line and outputs supply MFTs. The proposed traction converter concept with MFT replaces classical topology based on bulky line traction transformer and significantly reduces size and weight of the traction transformer. This paper describes in detail control algorithms and their implementation of the proposed converter configuration. The converter concept with common MFT using coupled magnetic flux for balancing input capacitor voltages and modular concept with separate power cell and individual MFTs have been discussed. The paper analyses in detail the matrix converter commutation based on standard 4-step commutation with respect to knowledge of input voltage polarity or output current polarity. The control algorithms also keep in touch the minimizing of the MFT magnetic saturation at extremely low switching frequency. The behaviour of the proposed converter power circuit has been analysed by simulations and verified by experimental test on developed low-scale functional prototype with rated power up to 4 kVA.

An non-uniformity voltage model for proton exchange membrane fuel cell

The fuel cell used in transportation has environmental protection, high efficiency and no line traction power system which can greatly reduce line construction investment. That makes it a huge potential. The voltage uniformity is one of the most important factors affecting the operation life of proton exchange membrane fuel cell (PEMFC). On the basis of principle and classical model of the PEMFC, single cell voltage is calculated and the location coefficients are introduced so as to establish a non-uniformity voltage model. These coefficients are estimated with the experimental datum at stack current 50 A. The model is validated respectively with datum at 60 A and 100 A. The results show that the model reflects the basic characteristics of voltage non-uniformity and provides the beneficial reference for fuel cell control and single cell voltage detection.

Traction with dental floss and endoscopic clip improves trainee success in performing gastric endoscopic submucosal dissection (ESD): a live porcine study (with video).

Endoscopic submucosal dissection (ESD) is a prolonged procedure with serious adverse events. The clip with line traction method was reported to improve ESD. However, there was no comparison with conventional ESD especially for trainees. We report here on the feasibility and efficacy of traction using dental floss with endoscopic clip to facilitate ESD versus conventional method for ESD trainees. Twenty simulated gastric lesions, paired with location and size, were created in porcine stomachs using a standard template. After a circular incision was made, submucosal dissection (control, n=10) was performed with standard ESD, while the study (clip, n=10) was performed with traction using dental floss and endoclip. Primary outcome was speed of submucosal dissection. Secondary outcome included frequency of submucosal injection and adverse event. Compared with controls, median procedure time was significantly shorter in the clip group (5.6±1.1 vs. 13.6±2.5min, P=0.003), with a significantly faster submucosal dissection time (1.8±0.3 vs. 0.6±0.1cm(2)/min, P=0.001) and less frequent submucosal injection (5.7±0.6 vs. 8.5±1.0 times, P=0.024). There were no perforations in either group, but less adverse events (bleeding and injury to muscularis propria) in the clip group (1 vs. 7, P=0.068, α=0.1). Traction provided by dental floss and endoclip improves visualization of the submucosal layer during ESD. It allows a faster and safer gastric ESD especially among trainees in the early learning phase.

Protection of bridges against stray current corrosion

A case study of Siennicki Bridge stray current corrosion hazard is presented. A corrosion risk was caused by incorrectly designed tram line traction which goes over the bridge. No dielectric insulation between running rails and bridge steel construction was used. A variety of protection methods against stray currents are described. Characteristics of the endangered bridge were described. Impressed current cathodic protection system against stray currents was proposed and designed at the Department of Electrochemistry, Corrosion and Materials Engineering, Gdansk University of Technology. Coupon technique measurements and potential measurements were performed to verify the effectiveness of the protection system.

Precision rheometry: Surface tension effects on low-torque measurements in rotational rheometers

For rotational rheometers, surface tension results in a torque that should not occur in an ideal, rotationally symmetric geometry. This paper identifies and explains the effect, which is due to surface tension and contact line traction forces, and not surface rheology at the liquid-air interface. For water, we show that this torque can be more than two orders of magnitude larger than the viscous torque. In steady shear flow, the effect appears as a constant torque independent of rate, which would appear inaccurately as apparent shear thinning of water. In oscillatory tests, this may appear inaccurately as an elastic modulus. This surface tension torque is sensitive to wetting conditions and contact line asymmetries and cannot be deterministically corrected in experimental measurements. It therefore raises the lower bound of the instrument low-torque limit. The surface tension torque is reduced by maximizing rotational symmetry of the contact line, minimizing evaporation and the migration of the contact line, reducing the radial location of the contact line, and lowering the surface tension. Identifying and eliminating the surface tension torque is critical for low viscosities, intrinsic viscosities, soft materials, subdominant viscoelastic components, small gaps, and any circumstance where the low-torque limit is experimentally important.

Medial subtalar dislocation: Case report

Subtalar dislocation (SI) is a term that refers to an injury in which there is dislocation of the talonavicular and talocalcanear joint, although the tibiotalar joint is intact. A case of medial subtalar dislocation as a result of basketball injury, so-called "basketball foot", is presented. Closed reposition in i.v. anaesthesia was performed with the patient in supine position and a knee flexed at 90 degrees. Longitudinal manual traction in line of deformity was carried out in plantar flexion. The reposition continued with abduction and eversion simultaneously increasing dorsiflexion. It was made in the first attempt and completed instantly. Rehabilitation was initiated after 5 weeks of immobilization. One year after the injury, the functional outcome was excellent with full range of motion and the patient was symptom-free. For better interpretation of roentgenogram, bone model of subtalar dislocation was made using the cadaver bone. Although the treatment of such injury is usually successful, diagnosis can be difficult because it is a rare injury, and moreover, X-ray of the injury can be confusing due to superposition of bones. Radiograms revealed superposition of the calcaneus, tarsal and metatarsal bones which was radiographically visualized in the anterior-posterior projection as one osseous block inward from the talus, and on the lateral view as in an osteal block below the tibial bone. Prompt recognition of these injuries followed by proper, delicately closed reduction under anaesthesia is crucial for achieving a good functional result in case of medial subtalar dislocation.

Poroelastic acoustic wave trains excited by harmonic line tractions

A two-dimensional boundary-value problem for a porous half-space with an open boundary, described by the widely recognized Biot's equations of poroelasticity, is considered. Using complex analysis techniques, a general solution is represented as a superposition of contributions from the four different types of motion corresponding to P1, P2, S and Rayleigh waves. Far-field asymptotic solutions for the bulk modes, as well as near-field numerical results, are investigated. Most notably, this analysis reveals the following: (i) a line traction generates three wave trains corresponding to the bulk modes, so that P1, P2 and S modes emerge from corresponding wave trains at a certain distance from the source, (ii) bulk modes propagating along the plane boundary are subjected to geometric attenuation, which is found quantitatively to bex−3/2, similar to the classical results in perfect elasticity theory, (iii) the Rayleigh wave is found to be predominant at the surface in both the near (due to the negation of the P1 and S wave trains) and the far field (due to geometric attenuation of the bulk modes), and (iv) the recovery of the transition to the classical perfect elasticity asymptotic results validates the asymptotics established herein.

Modelling of plane strain interfacial fracture in incompressible materials

Abstract Numerical modelling of a photoelastic experiment is discussed. The experiment examined incompressible materials under plane strain conditions, which results in a simplified analysis owing to a vanishing of the bimaterial parameter. The photoelastic experiment used the stress freezing method to determine near tip stresses in interfacial cracks in bimaterial specimens. Different crack orientations were used to produce different mode mixities. Photoelastic fringe patterns were analyzed to determine the magnitude and phase angle of the complex stress intensity factor. These experiments were modeled using a finite element analysis to determine the field variables near the tips of the interfacial cracks. Magnitudes of the complex stress intensity factors are found from J integral values, derived using the domain integral approach, and the phase angles are determined using extrapolation of the bond line traction data to r =0. The results show that this approach is a useful way to characterize completely the complex stress intensity factor in incompressible linear elastic bimaterial combinations under plane strain conditions.

An efficient and accurate calculation of traction in elastohydrodynamic contacts

Traction calculation is an important step in the design and lubrication optimization of machine components with elastohydrodynamic (EHD) contacts. The availability of an accurate and robust method of calculation can be a valuable tool for the machine designer. This paper presents a method of traction calculation that combines the key features of the full numerical approach and previously reported approximation methods. Specifically, the contact pressure and the film thickness are approximated by closed-form expressions while the temperature distribution is numerically calculated using a finite difference method. This scheme of calculation largely eliminates the numerical instability problem that frequently occurs in the full numerical approach while yielding results much more accurate than those obtained by previous approximation methods. The method is robust and allows the use of any rheological models for the lubricant. It is relatively easy to implement on a computer to efficiently calculate traction in both line and point EHD contacts.

Comparison of Skeletal Traction Forces in Patients Treated in Conventional and Oscillating Hospital Beds

This study compares the forces in two types of skeletal traction systems: a standard hospital bed with balanced suspension traction and an oscillating hospital bed using a flexion cable system. In line traction, forces were continuously measured, using a specially designed transducer. Changes in the magnitude of traction forces of up to two times the applied force were caused by patient movement, nursing procedures, and changes in bed configuration. The oscillating hospital bed was found additionally to impart a moderate (20-50%) rhythmic, sinusoidal variation in applied traction forces. The traction forces applied with the flexion cable system on the oscillating hospital bed were well tolerated and equivalent to those applied in conventional balanced suspension on a standard hospital bed. Although different in design, standard balanced suspension traction on a conventional hospital bed and traction using the flexion cable system on the oscillating hospital bed appear to be equally effective in stabilizing fracture sites.

The role of the adhesive layer in a double cantilever joint

The problem of a double cantilever beam adhesive joint is reconsidered under the assumption of cohesive fracture within the adhesive bond layer. After properly accounting for the adhesive layer, the problem is reduced to a Fredholm integral equation of the second kind for the bond line traction. Numerical results for the bond line stress distribution and the crack tip stress intensity factor are presented for several combinations of the governing material and geometrical parameters.