Tension Adjustment Research Articles

Cross Intrinsic Transfer for Ulnar Drift in the Rheumatoid Hand Under Wide Awake Local Anesthesia No Tourniquet - Surgical Technique

This article introduces a surgical technique for cross-intrinsic transfers (CIT) to correct ulnar drift in rheumatoid hands performed under wide-awake local anesthesia no tourniquet (WALANT). This approach allows real-time adjustment of tendon transfer tension and active patient participation in hand movements and deformity correction during the procedure. It can be combined with other surgeries such as prosthetic replacement arthroplasties of the MCP joints. The technique was applied to six patients, resulting in a significant reduction of ulnar deviation from an average of 70° preoperatively to 8° postoperatively. All patients reported high satisfaction with good outcomes.

Numerical simulation of fabric cold pad-batch winding and quality assessment of fabric in roll

Proper fabric winding quality is crucial for achieving desired finishing effects in cold pad-batch dyeing. In this work, a detailed 3D finite element model and assessment criteria were established to analyze the influences of winding pattern, pick-up, and tension function on fabric winding quality, revealed the complex relationship between winding process and fabric roll shape. Material viscoelasticity’s time-dependent effects on stress distribution were considered. Results show that employing a following roller effectively suppresses tangential creases and axial streaks but increases seam imprints and reduces fabric roundness. Increasing pick-up improves winding quality by reducing creases, streaks, and compression deformations. However, it also elevates internal radial stress, hindering control over seam imprints. Winding with variable tension, conicity coefficient α and power index i have significant impacts on coiling quality. In addition, increasing α or decreasing i effectively enhances winding quality, with the power function performing better in tension adjustment and overall winding quality.

A three-dimensional pseudo-potential multiphase model with super-large density ratio and adjustable surface tension

In this paper, an improved three-dimensional pseudo-potential multiphase flow model is proposed. A high-precision difference scheme is employed to improve the computational accuracy of the interaction forces to achieve super-large density ratio. The present model is verified to obtain two-phase density ratio up to hundreds of thousands for all selected equations of state, and the spurious currents can be suppressed to a relatively low level. A modification pressure tensor is introduced to implement a wide range of surface tension adjustments independently of the density ratio. The model is applied to simulate droplet impacts on a liquid film as well as droplet impacts on a dry surface. Numerical results show that the model still has good numerical stability in simulating complex fluid problems with very large density ratio, adjustable surface tension, high Reynolds number, or containing the wettable surface. In addition, to improve the computational efficiency, an efficient parallel algorithm based on graphics processing unit (GPU) is designed for the present model. A maximum speedup ratio of 687 times is obtained compared to the corresponding CPU-based serial algorithm, which can significantly accelerate the numerical simulation study.

What Are the Factors That Enable Thread Lifting to Last Longer?

Thread-lifting traditionally addressed aging-related skin laxity by leveraging precise thread placement and traction. However, recent advancements, notably cog threads, expanded its application to younger patients seeking facial contour refinement. These newer threads effectively lift sagging areas and refine facial contours, broadening the procedure’s appeal. Challenges arise in selecting threads due to variable physician preferences and patient needs. Clear indications for thread efficacy are vital for credibility and tailored selection. Thread choice depends on tissue laxity, necessitating lighter threads for minimal laxity and stronger ones for significant sagging. However, no single thread universally suits all cases. Combining different threads is favored for optimal outcomes and minimizing side effects. Excessive traction post-procedure may lead to prolonged discomfort and skin irregularities. Post-procedural tension adjustments through massage remain debated, potentially conflicting with minimally invasive principles. Understanding thread characteristics guides tailored selection, considering patient conditions and procedural goals. This comprehensive understanding extends beyond specific products, aiming for optimal outcomes in thread-lifting procedures. Key factors influencing outcomes encompass thread materials, thickness, cog shapes, insertion depth, lifting vectors, and absorbable thread expiration dates.

Corset suture: A novel technique of overlay appositional continuous sutures with air tamponade for management of large acute corneal hydrops.

Management of large acute corneal hydrops (ACH) has always been a challenge. Various medical and surgical management options have been used, such as topical steroids, cycloplegics, antiglaucoma medications, antibiotics, Descemet's membrane reposition, and pre-Descematic sutures, for the management of acute hydrops, but have shown limited benefit. We hereby describe a novel technique of appositional continuous overlay sutures along with air tamponade for surgical management of corneal edema following large ACH. In this technique, the epithelium is scraped to visualize the stromal cleft, and then corneal marking is done to locate the suture placement site. Next, a continuous overlay, 10-0 nylon suture is passed in a crisscross fashion, just like the laces of a corset. A small paracentesis is made to lower the intraocular pressure. Stromal fluid is milked out using two iris spatulas, simultaneous suture tension adjustment is done, and the knot is secured. Appropriate anterior chamber tamponade is achieved using air, paracentesis is hydrated, and a bandage contact lens is applied. We noted complete resolution of corneal edema within 2 weeks of the procedure, with significant improvement in visual acuity.

Optimizing pectoralis major tendon repair: a modified knotless suture anchor technique using high-strength suture and tape

BackgroundRupture of the pectoralis major tendon is infrequent but has shown an increased incidence in athletes, particularly weightlifters during bench presses. Various techniques for repair exist, yet no established gold standard has been defined. MethodsWe present a modified surgical technique utilizing knotless suture anchors for pectoralis major tendon repair. The technique involves bringing the tendon end superiorly and inferiorly to the decorticated bone surface, ensuring broader tendon-to-bone contact. Knotless anchors with a unique suture locking mechanism facilitate tension adjustment. Additionally, the repair's strength is reinforced by employing both surgical tape and high-strength suture. ResultsThe utilization of both surgical tape and high-strength suture in conjunction with knotless suture anchors provides a secure and stable construct. This approach minimizes the risk of failure, reduces the potential for neurovascular injury associated with bicortical drilling, preserves imaging quality due to the absence of metal artifacts, and helps avoid the risk of fracture associated with traditional methods. However, surgeons should be aware of a potential disadvantage of increased surgical costs compared to traditional techniques. ConclusionsOur modified technique offers multiple advantages, including increased tendon-to-bone contact, enhanced stability, reduced neurovascular risks, and avoidance of potential fractures. This makes it a valuable option for successful pectoralis major tendon repairs. Surgeons should consider its benefits and weigh them against the associated costs for optimal patient care.

Suppression of Railway Catenary Galloping Based on Structural Parameters’ Optimization

Railway catenary galloping, induced by aerodynamic instability, poses a significant threat by disrupting the electric current connection through sliding contact with the contact wire. This disruption leads to prolonged rail service interruptions and damage to the catenary’s suspension components. This paper delves into the exploration of optimizing the catenary system’s structure to alleviate galloping responses, addressing crucial parameters such as span length, stagger dropper distribution, and tension levels. Employing a finite element model, the study conducts simulations to analyze the dynamic response of catenary galloping, manipulating structural parameters within specified ranges. To ensure accurate and comprehensive exploration, the Sobol sequence is utilized to generate low-discrepancy, quasi-random, and super-uniform distribution sequences for the high-dimensional parameter inputs. Subsequent to the simulation phase, a genetic algorithm based on neural networks is employed to identify optimal parameter settings for suppressing catenary galloping, taking into account various constraints. The results gleaned from this investigation affirm that adjusting structural parameters can effectively diminish the galloping amplitude of the railway catenary. The most impactful strategy involves augmenting tension and reducing span length. Moreover, even when tension and span length are fixed, adjusting other parameters demonstrates efficacy in reducing galloping amplitudes. The adjustment of messenger-wire tension, dropper distribution, and stagger can achieve a 22.69% reduction in the maximum vertical galloping amplitude. Notably, maintaining a moderate stagger value and a short steady arm–dropper distance is recommended to achieve the minimum galloping amplitude. This research contributes valuable insights into the optimization of railway catenary systems, offering practical solutions to mitigate galloping-related challenges and enhance overall system reliability.

Simulation of droplet dynamics in an inclined channel considering contact angle hysteresis using the cascade lattice Boltzmann method

Modeling droplet dynamics on solid surfaces with rough or chemically heterogeneous walls is crucial in various industrial applications. In such cases, the downstream and upstream contact lines of the droplet usually move incongruously, leading to droplet deformation known as the contact angle hysteresis (CAH) phenomenon. In this work, we developed a cascaded multicomponent Shan–Chen lattice Boltzmann method to simulate droplet dynamics considering the CAH. Specifically, the Peng–Robinson equation of state is added to one component to improve the density ratio of the model. By modifying the fluid–fluid interaction force scheme, we achieve thermodynamic consistency and independent adjustment of the surface tension. We also implement the modeling of CAH by applying geometric wetting boundaries with a hysteresis window. Based on this model, we first simulated pinned droplets in inclined channels with different hysteresis windows. We obtain the critical tilt angle of the droplet at the onset of sliding, which agrees with the theoretical result. For sliding droplets in the inclined channel, our results reveal that a slight tilt angle is unfavorable for the upstream portion of the droplet sliding, while a large tilt angle is favorable for the entire droplet sliding. A small receding angle results in a large droplet deformation at the quasi-steady state. Finally, by periodically transitioning between different hysteresis windows, enabling exclusive sliding of the upstream contact line during the first half period and subsequent sliding of the downstream contact line during the second half period, we successfully observed the stick-slip phenomenon of the droplet.

Arthroscopic pullout repair versus suture anchor repair for medial meniscus posterior root tear combined with high tibial osteotomy

BackgroundThe aim of this study was to compare the outcomes of pullout repair with a metal button and suture anchor repair for medial meniscus posterior root tears in patients undergoing high tibial osteotomy with varus alignment. MethodsPatients who underwent arthroscopic pullout repair (P group) and suture anchor repair (SA group) in combination with open-wedge high tibial osteotomy between 2018 and 2021 were retrospectively examined. Patients who received second-look arthroscopy at 1 year and at least 2 years of follow up were included. Structural healing (complete/partial or failed healing) and chondral lesions at the initial surgery and the second-look arthroscopy, radiographic parameters around the knee, Lysholm score, and Tegner activity scale (before and 2 years after surgery) were compared. ResultsA total of 88 patients (68 women/20 men, mean age 61.1 ± 7.9 years old) were included in the analysis. Of these, 51 patients underwent pullout repair, while the other 37 underwent suture anchor repair. The SA group showed a significantly higher rate of complete healing (64.9%) than the P group (21.6%, P < 0.001). The Lysholm score significantly improved after surgery in both treatment groups. At the final follow up, the SA group had a significantly higher Lysholm score (89.6 ± 10.7) than the P group (80.9 ± 17.4, P = 0.011). ConclusionArthroscopic suture anchor repair had superior healing status and Lysholm Score in comparison with pullout repair with a metal button, as it achieved better tension adjustment. This result is meaningful particularly when medial meniscus root repair and high tibial osteotomy are performed simultaneously.

Transobturator Tension-Free Vaginal Flap Operation versus Synthetic Transobturator Tape for Treatment of Female Stress Urinary Incontinence: A Prospective Randomized Study

Introduction: Synthetic mid-urethral slings (MUSs) are the gold standard treatment for female stress urinary incontinence (SUI). Recently, there have been reports of serious adverse events with synthetic tapes such as urethral erosion, vaginal erosion, and mesh infection. Tension-free vaginal flap (TVF) operation has been proven to be successful as a natural alternative to synthetic slings. We propose our novel technique, the transobturator tension-free vaginal flap (TO-TVF), utilizing native vaginal tissue and being suspended via transobturator route. Methods: This prospective study was conducted on 72 female patients with SUI, presenting at Alexandria University Hospital. Patients were randomized into 2 groups, group 1: 37 patients subjected to TO-TVF and group 2: 35 patients to conventional transobturator tape (TOT). In TO-TVF, a rectangular vaginal wall flap is created. A polypropylene monofilament mesh is sutured to each edge of the vaginal flap. This is inserted like conventional outside-in TOT. Patients were subjected to PGI and UDI-6 questionnaires and urodynamic study before and 6 months postoperatively. Results: Both groups showed comparable and significant improvements in questionnaires. Mean operative time for TO-TVF and conventional TOT was 26.31 ± 5.2 min and 21.8 ± 3.1 min, respectively. Cure rate was 89% in group 1 and 91.4% in group 2, which was not statistically significant. No significant intraoperative complications were encountered. We had no cases of vaginal or urethral erosion in both groups. Conclusions: TO-TVF is a cost-effective, feasible, safe, and effective surgical alternative to synthetic MUS. Synthetic mesh tissue anchoring properties are maintained for better adjustment of tension. However, long-term follow-up on a large cohort of patients is still needed.

Среднеуретральный синтетический слинг с возможностью ранней мобилизации в лечении недержания мочи при напряжении у женщин.

Introduction. The use of midurethral synthetic slings is currently considered to be the most widespread treatment option for stress urinary incontinence (SUI). The most difficult in the existing approaches is to achieve the optimal tension of the sling, on which the result of treatment directly depends. To solve this problem, sling systems with the possibility of tension adjustment in the early postoperative period were created. A comparative study of the effectiveness and safety of such a system and a sling without the possibility of adjustment seems to be a relevant task. Materials and Methods. The study involved 320 female patients with a mean age of 55.2±11.2 years and a confirmed diagnosis of SUI. The patients were allocated into two groups: the first group underwent a synthetic suburethral sling by the standard technique (TOT); the second group received a suburethral sling with early mobilization (TTT). All patients underwent stress test, uroflowmetry and ultrasound investigation to determine the volume of residual urine. UDI-6, ICIQ-SF, PISQ-12 questionnaires were filled out to assess subjective efficiency. Results. In the second group, 28% of the patients needed to increase the tension of the prosthesis. Due to the possibility of tightening the sling in the early postoperative period, the operation was ineffective at the delayed follow-up stage at 36 months only in 11% of the women in the TTT group and in 32% of the patients in the LTT group, p&lt;0.001. Loosening the sling tension was required in every fourth patient in the TTT group. Signs of obstructive urination at the stage of 36 months persisted in 13 patients in the TOT group and were completely absent in the TTT group. Subjective satisfaction with treatment was higher in the TTT group and amounted to 82%. Conclusion. A synthetic mid-urethral tuneable tension tape is superior to a classic sling without adjustment capability in long-term efficacy and safety.

Neuro-control adjustment of conveyor belt tension

Goal.Identification of ways to improve the quality indicators of conveyor operation during their design and construction using modern automation elements, automatic control systems, and the application of neural controller systems for automatic support of optimal technological processes during material transportation. Research methodology. The proposed methodology involves supervisory training of a neural controller system for automatic tensioning of the conveyor belt using the MATLAB software package. Research results. A sequence for building and training an imitation neural control system for regulating (supporting) the optimal tension of the conveyor belt has been developed and investigated using the MATLAB software package. It was established that for systems containing elements with significant time constants, it is advisable to experimentally determine the ratio of the number of training stages to the number of segments during supervisory training of the neural controller. Scientific novelty. The article proposes the construction of an imitation model of a tension control system for a conveyor belt using artificial intelligence and the implementation of a neural controller. This approach allows for preliminary tuning of the developed control system and its utilization in the design phase of similar objects. Practical significance. The sequence for constructing an imitation model of an optimal tension control neural system for a conveyor belt can be applied in the design and investigation of similar mechanisms. The system is adaptable and enhances reliability while maintaining desired performance parameters. The model can be recommended for preliminary determination of neural controller parameters, regulator system tuning, obtaining predicted transient processes, and improving work productivity.

A Patella-Sided Tensioning Technique for Medial Patellofemoral Ligament Reconstruction

Reconstruction of the medial patellofemoral ligament (MPFL) is a common procedure for treatment of recurrent patellofemoral instability. Over the last two decades, multiple surgical techniques for MPFL reconstruction have been described with no clear consensus on a superior reconstruction technique. Appropriate graft tensioning is one of the most important factors for a successful MPFL reconstruction. Overtensioning of the MPFL graft can lead to patellofemoral joint overload and undertensioning can lead to recurrent instability. Current literature demonstrates descriptions of MPFL reconstruction with final graft tensioning performed off of the femoral side. We describe a technique in this article for performing final graft tensioning from the patellar side, which gives the surgeon an option for intraoperative tension adjustments after evaluating patellar tracking.

Dynamic analysis of the effect of mesh tension on the deployment process of loop antenna

In orbit deployment and profile maintenance are the most important functional requirements in the development of loop antenna If the antenna cannot be deployed in orbit, it will lose the signal transmission function, and the profile in orbit holding function is related to whether the antenna can stably transmit electromagnetic signals. The mesh tension (main mesh tension, rear mesh tension and tension arrays tension) is the key means to maintain the profile stability in orbit. At the same time, it is also closely related to the rod load and the maximum motor driving force in the process of antenna deployment. Based on the theory of flexible multi-body dynamics, the dynamic modeling of the deployment process of ten meter loop deployable antenna is established in this paper On this basis, the influence of mesh tension on the deployment dynamics of loop antenna is analyzed by using the control variable method, and its related variation law is obtained. This study can provide guidance for the tension adjustment in the profile adjustment stage of the ring antenna, so as to shorten the development cycle, and can also predict the deployment of the antenna in orbit.

Mechanism for tension adjustment in tendon driven remote center-of-motion mechanism for minimally invasive surgery

Tendon drive is used for transmission design in applications ranging from wearable rehabilitation and surgical robots to industrial robots. For their efficient operation, one of the principal design requirements is to have adequate tension in the tendon element. This paper introduces a novel mechanism for tension adjustment using a secondary cable-pulley arrangement via a lever mechanism. An adjustment in a tension spring applies a force in the tendon element meant for the transmission of remote centre-of-motion (RCM) mechanism for medical robotic application. Thereafter, the current work presents the kinematic and force analyses of the proposed concept along with a series of plots of various mechanism parameters. The variation of these parameters is in good agreement with the physical motion of the devised mechanism. As compared to the conventional methods of tension adjustment, the proposed concept is a better solution for problems that arise due to low manufacturing tolerances and the need for independent tension adjustment in a multi degrees-of-freedom tendon driven RCM mechanism. In the preferred embodiment, it is proposed to use cables (wire-ropes) as tendon elements to drive a mechanically constrained double-parallelogram-based RCM mechanism which is extensively used for Minimally Invasive Surgery. From this implementation, it is learnt that the presented mechanism can be implemented in several configurations. However, this paper presents the preferred embodiment only which meets the demand, of invariant tendon length, of the RCM mechanism under consideration. An initial prototype is made from acrylic sheets, PLA material, and standard elements (like bearings, pulleys, aluminum pins, 0.5 mm stainless-steel wire-rope, etc.) using laser micromachining and 3D printing.

Medial patellofemoral ligament reconstruction: A review.

Introduction:Reconstruction of the medial patellofemoral ligament (MPFL) is an effective surgical method for the treatment of lateral patellar instability. At present, there is not much controversies regarding the femoral attachment, however, the controversies regarding patellar attachment versus attachment, number of graft strands, tension, isometry and so on. The following electronic databases will be searched: PubMed, the Cochrane Library, Embase, Web of Science, Medline. We will consider articles published between database initiation and March 2021. MPFL in the subject heading will be included in the study. Language is limited to English. Research selection, data extraction, and research quality assessment were independently completed by 2 researchers.Conclusions:MPFL reconstruction is a reliable technique for the treatment of patellofemoral instability. The Schöttle point is still the mainstream method for locating the femoral attachment, the patellar attachment for single-bundle is located at the junction of the proximal one third and the distal two third of the longitudinal axis of the patella. For double-bundles, one is located in the proximal one third of the medial patellar edge and another is in the center of the patellar edge. Meanwhile, the adjustment of graft tension during operation is very important.

A modified Altis® mid-urethral sling that allows immediate post-operative adjustment: experience in 197 patients.

The transobturator mid-urethral Altis® "mini-sling" uses a static and a dynamic anchor on either end of a pulley suture for intraoperative tension adjustment. Given the potential for incorrect tensioning with sling placement, we adopted a modification for post-operative adjustment should stress urinary incontinence (SUI) persist. The objective is to describe technique, rate of postoperative adjustment driven by patient symptoms, and impact of preoperative/intraoperative variables. In this single-surgeon experience, retrospective chart review, demographic and clinical data were collected on patients who received the Altis® sling for SUI between 2014 and 2019. We used descriptive statistics and three-group comparison tests to assess difference in variables among tightening, loosening, or no adjustment. Altis® sling placement was performed on 197 female patients with an average age of 58.7years. Eighty-four percent (165/197) did not receive post-operative adjustment. Of the 32 patients with post-operative adjustment, 8 (4.1%) had loosening and 24 (12.2%) had tightening at an average of 10.5days post-operatively. All tightening procedures were done in the clinic. Of the 8 patients with post-operative loosening, 6 were performed in clinic and 2 in the operating room. Preoperative and intraoperative variables were not significantly different among tightening, loosening, and no adjustment cohorts. This modification of the Altis® sling provides surgeons with the ability to tighten and loosen the sling for persistent SUI. All tightening and most loosening procedures were able to be performed in the clinic. The ability to easily tighten a sling in the early post-operative period may be a critical advantage.

Optimal placement and sizing of distributed generation for loss minimization using ABC optimization

The distributed generation (DG) refers to the use of the nearby units of small generation or in the sleefelzentres. Revisions have shown that unfitting choice of the position and scope of the DG can lead to bigger system sufferers than DG's sufferers. Public services are already available before the high loss of energy loss and of the mediocre voltage profile, in particular developing countries cannot tolerate any increase in losses. From optimal allocation, public services in the reduction of system losses improve tension adjustment and improve delivery reliability. This article aims to minimalize the annual system's annual loss through the appropriate positioning and size of the DG units. The artificials bee colony (ABC) of EPA are inspired by the behavior of the API feeding, this method is incredibly conventional, a stroke or a peoplated stochastic optimization algorithm to meet the solution of the specified problem. At MATLAB, a probabilistic approach is simulated to reach the target indicates that the size of the DGs to be installed to reduce almost the same loss as a percentage that the situation in which the load power is considered constant.

Optimal placement and sizing of distributed generation for loss minimization using ABC optimization

The distributed generation (DG) refers to the use of the nearby units of small generation or in the sleefelzentres. Revisions have shown that unfitting choice of the position and scope of the DG can lead to bigger system sufferers than DG's sufferers. Public services are already available before the high loss of energy loss and of the mediocre voltage profile, in particular developing countries cannot tolerate any increase in losses. From optimal allocation, public services in the reduction of system losses improve tension adjustment and improve delivery reliability. This article aims to minimalize the annual system's annual loss through the appropriate positioning and size of the DG units. The artificials bee colony (ABC) of EPA are inspired by the behavior of the API feeding, this method is incredibly conventional, a stroke or a peoplated stochastic optimization algorithm to meet the solution of the specified problem. At MATLAB, a probabilistic approach is simulated to reach the target indicates that the size of the DGs to be installed to reduce almost the same loss as a percentage that the situation in which the load power is considered constant.

Optimizing scheme for tension re-allocation of two collaborative RUAVs: An experimental study

The collaborative aerial transportation (CAT) of multiple rotorcraft unmanned aerial vehicles (RUAVs) collaboratively carrying a cable-suspended payload provides a feasible way to ship a heavy load by multiple small-sized RUAVs. Usually, the formation of the RUAVs for CAT has to be pre-designed according to the tension assignment on each RUAV, and maintained via control during flight. However, in case the tension assignment needs to be adjusted during flight, the formation of the RUAVs needs to be re-allocated accordingly. This situation may occur due to the changing circumstances, such as fuel condition, maximum payload capability, payload re-assignment, etc. In this paper, we propose an optimizing scheme for the re-allocation of two-RUAV CAT (TR-CAT) system to meet the commanded tension adjustment. A novel optimization structure is formulated with respect to the adjustable tension requirement, while multiple constraints, including task, safety, as well as dynamic constraints, are provided for the optimization formulation. The differential flatness of the TR-CAT system is also analyzed and proved. Besides the simulation validations, indoor and outdoor experiments were conducted on a real CAT system to demonstrate the efficacy of the proposed scheme.