Lateral Suspension Research Articles

Analysis of coupled suspension lateral dynamics characteristics based on suspension moment centre and non-steady tyre model

This paper presents an analytical approach for developing a coupled suspension lateral dynamics model to investigate lateral vibration characteristics. The concept of the suspension moment centre was introduced. The direction of the constraint reaction force from the independent suspension control arm is perpendicular to the tyre contact speed. This arrangement leads to a larger lateral movement of the suspension hub as the height of the moment centre increases. According to the coupled suspension lateral dynamics model, experimental results were used to validate the relationship between wheel camber, lateral displacement of wheel centre and wheel travel. The non-steady state lateral suspension force was calculated based on the tyre slip ratio, defined as the lateral speed relative to the rolling speed, and the system dynamics characteristics was analysed. The results show that under excitation from an uneven road surface, the root mean square value of the suspension lateral force initially increases and then decreases as vehicle speed increases. Additionally, the root mean square value of the suspension lateral force increases with the increase in tyre relaxation length.

Comparison of sexual function between laparoscopic lateral suspension and laparoscopic sacrocervicopexy with the use of the PISQ-IR questionnaire

Introduction and hypothesisWe aimed to analyze the quality of sexual life of patients with apical vaginal wall prolapse who had undergone laparoscopic lateral suspension (LLS) and laparoscopic sacrocolpopexy (LSC).MethodsWe performed a secondary analysis of sexual outcomes of a previous randomized control trial comparing LLS and LSC in 89 women with symptomatic POP stage ≥ II. We evaluated sexually active (SA) and non-sexually active women (NSA) using the Pelvic Organ Prolapse/Incontinence Sexual Questionnaire-IUGA-Revised (PISQ-IR). Women were reviewed over a period of 1 year post-surgery.ResultsAnalysis of the entire PISQ-IR questionnaire indicates that surgical treatment of POP resulted in an improvement of the quality of sexual life in 21 (80.76%) in the group of sexually active women after LSC and in 20 (83.33%) in the group of SA patients after LLS. In both groups of patients, dyspareunia was not observed.ConclusionIn conclusion, the quality of sexual life in SA group of patients improved significantly after both surgical procedures. The quality of sexual life of surveyed women significantly improved after curing POP symptoms.

Variant of Laparoscopic Lateral Suspension of the Uterus by Autologous Tissue (Round Ligament): A case study

Variant of Laparoscopic Lateral Suspension of the Uterus by Autologous Tissue (Round Ligament): A case study

Laparoscopic lateral suspension with mesh for severe anterior and apical pelvic organ prolapse: an observational cohort study for safety and efficacy at 2-year follow-up.

This study aimed to investigate the clinical safety and efficacy of laparoscopic lateral suspension (LLS) with mesh in the treatment of severe anterior and apical pelvic organ prolapse (POP) Chinese women with a 2-year follow-up. We conducted an observational cohort study. Sixty patients who presented apical (uterovaginal or vault) and anterior prolapse at stage 3 or higher were enrolled. The LLS surgical procedure was performed in accordance with Dubuisson standard operation. The objective and subjective cures as well as the surgery-related complications were evaluated. The POP-related questionnaires were used to evaluate the quality of life before operation and at 24months after operation follow-up. Objective cure rates at 2years of follow-up were 88.3% for the anterior compartment, 100% for the apical compartment and 93.3% for the posterior compartment. The subjective cure rate reached to 93.3%. There were statistically significant lower scores of thepelvic floor impact questionnaire-7 (PFIQ-7) and the pelvic floor distress inventory-short form-20 (PFDI-20)for all women after surgery and they exhibited similar scores of the pelvic organ prolapsed-urinary incontinence sexual questionnaire-12 (PISQ-12) (P = 0.317). And no significant difference was demonstrated in international consultation on the incontinent questionnaire short form (ICI-Q-SF) (P = 0.551). No major complications associated with LLS were observed in our study. We consider that LLS with mesh operation is safe, feasible and effective to correct severe apical and anterior POP after 2-year follow-up.

Transvaginal Natural Orifice Transluminal Endoscopic Surgery (vNOTES) in Urogynecological Surgery: A Systematic Review.

Background: Minimally invasive surgery could improve cosmetic outcomes and reduce the risks of surgical injury with less postoperative pain and a quicker patient's discharge. Recently, transvaginal natural orifice transluminal endoscopic surgery (vNOTES) has been introduced in urogynecology with exciting results. Evidence Acquisition: After PROSPERO registration (n°CRD42023406815), we performed a comprehensive literature search on Pubmed, Embase, and Cochrane CENTRAL, including peer-reviewed studies evaluating transvaginal natural orifice transluminal endoscopic surgery. No limits on time or type of study were applied. Evidence synthesis: Overall, 12 manuscripts were included in the analysis. Seven studies evaluated uterosacral ligament suspension, four studies evaluated sacral colpopexy, three evaluated sacrospinous ligament suspension, and one study evaluated lateral suspension. Overall success rates were high (>90%); however, definitions of success were heterogeneous. In terms of complication, most of the studies reported low-grade complications (Clavien-Dindo I and II); only two patients needed mesh removal because of mesh exposure. The risk of bias of the trials was rated in the medium to high-risk category. Conclusions: The present review highlights important initial results for vNOTES. Future randomized clinical trials are needed to better define its role in the management of urogynecological procedures.

Carbody swaying suppression for a high-speed rail vehicle by utilising active lateral suspension control

This study proposes the use of active lateral secondary suspension (ALS) to address low-frequency carbody swaying in high-speed rail vehicles under low wheel-rail conicity conditions. Field experiments reveal lateral acceleration exceeding 0.10 g at a dominant frequency of 1.4 Hz, with a Sperling index exceeding 3.0 during carbody swaying occurs. By integrating field-measured wheel/rail profiles and yaw damper parameters into a multibody dynamics model of vehicle system, the coupling between bogie hunting and carbody yaw and upper-center roll modes is identified as the root cause of swaying. Evaluating classic sky-hook ALS controls, damping control proves highly effective. Doubling the damping coefficient and blow-off force becomes essential when only half of the four actuators per vehicle are active. Stiffness control adjusts carbody suspension modal characteristics to prevent resonances with the bogie hunting mode, effectively suppressing swaying. In contrast, inerter control exhibits limited efficacy. Semi-active control, with optimised gain settings, can also alleviate swaying, with control system delay identified as a critical factor, suggesting a 100 ms limit for effective swaying suppression.

The standardized procedure, technical key points and latest progress of laparoscopic lateral suspension surgery.

Pelvic organ prolapse (POP) is a common condition that can affect up to 30% of women over the age of 50. For a long time, open abdominal and laparoscopic sacrocolpopexy (LSCP) have been considered the gold standard in the treatment of apical pelvic organ prolapse (POP). Promontory dissection may expose patients to potential life-threatening intraoperative vascular injuries, as well as damage to sacral roots or the hypogastric nerve. Laparoscopic lateral suspension could be considered as an alternative to LSCP in the treatment of POP due to its favorable objective and subjective outcomes. The aim of this article is to demonstrate a step-by-step approach to laparoscopic lateral suspension for POP with the goal of standardizing this procedure. Technical key points and the latest progress are summarized to provide a reference for subsequent gynecological and urological surgeons. According to our surgical experience of our hospital, demonstrate a step-by-step approach and highlight technical key points for laparoscopic lateral suspension for POP with the aim of standardizing this procedure. LLS with mesh is a safe alternative to laparoscopic sacropexy and is very well suited for uterine-preserving POP surgery. Nevertheless, this novel procedure lacks standardization. Standardization of procedures is necessary to reduce failure rates, generate impactful research data, and enhance patient safety. This article contributes to the standardization of this procedure, and we believe our article will be useful in assisting future gynecological and urological surgeons in performing this procedure.

Study of Resonance between Bogie Hunting and Carbody Mode via Field Measurements and Dynamic Simulation.

By addressing the phenomenon of carbody abnormal vibrations in the field, the acceleration of the carbody and bogie was measured using accelerometers, and the diamond mode of the carbody was identified. The equivalent conicity of the wheelset and the acceleration at the frame end indicated that the shaking of the carbody was caused by bogie hunting. In the SIMPACK simulation, the acceleration frequency and amplitude at the frame end and midsection of the side beam were calculated. The lateral deformation amplitude of the side beam in the finite element model was extracted, and a modal shape function for the diamond-shaped mode was established. By utilizing the modal vibration equation, the modal generalized forces of the carbody were computed, revealing that, during carbody shaking, the yaw damper force contributed significantly among the forces of the secondary suspension, with the phase difference between the front and rear bogies approaching 180°. This insight offers a novel perspective for subsequent active control strategies. Subsequently, these modal generalized forces were applied as external excitation to a coupled vibration model encompassing both the carbody and transformer. Aiming to reduce the acceleration amplitude at the side beam, the transformer was treated as a dynamic vibration absorber, allowing for the optimization of its lateral suspension parameters. As a result, the lateral and vertical acceleration amplitudes at the side beam were concurrently reduced, with the maximum decrease reaching 58.5%, significantly enhancing the ride comfort.

Role of lateral suspension for the treatment of pelvic organ prolapse: a Delphi survey of expert panel

Introduction and hypothesisLateral suspension is an abdominal prosthetic surgical procedure used to correct apical prolapse. The procedure involves the placement of a T-shaped mesh on the anterior vaginal wall and on the isthmus or uterine cervix that is suspended laterally and posteriorly to the abdominal wall. Since its description in the late 90s, modifications of the technique have been described. So far, no consensus on the correct indications, safety, advantages, and disadvantages of this emerging procedure has been reached.MethodsA modified Delphi process was used to build consensus within a group of 21 international surgeons who are experts in the performance of laparoscopic lateral suspension (LLS). The process was held with a first online round, where the experts expressed their level of agreement on 64 statements on indications, technical features, and other aspects of LLS. A subsequent re-discussion of statements where a threshold of agreement was not reached was held in presence.ResultsThe Delphi process allowed the identification of several aspects of LLS that represented areas of agreement by the experts. The experts agreed that LLS is a safe and effective technique to correct apical and anterior prolapse. The experts highlighted several key technical aspects of the procedure, including clinical indications and surgical steps.ConclusionsThis Delphi consensus provides valuable guidance and criteria for the use of LLS in the treatment of pelvic organ prolapse, based on expert opinion by large volume surgeons’ experts in the performance of this innovative procedure.

Design method for suspension parameters of high-speed railway vehicles considering uncertainties

A design method for suspension parameters is proposed to ensure the desired performance of a railway vehicle despite uncertainties. The method used in this study consists of two loops: a sub-loop, which uses parameter uncertainties to determine the minimum value of target performance, and a main loop, which optimises suspension parameters such that the minimal performance achieves Pareto optimality. Thus, by selecting a suitable Pareto solution that ensures the minimum performance is equal to or higher than the required performance, the robustness of the designed vehicle against the parameter uncertainties can be achieved. The lowest low-frequency damping ratio in the service speed range was selected as one of the design targets. The other target was the critical speed. Two wheel-rail contact characteristics were applied, considering the worst conditions for each design target. The distribution of the parameter uncertainties that minimised the vehicle performance showed distinct characteristics between the longitudinal and lateral suspension parameters, which provides useful information for the maintenance of railway vehicles. The performance analysis for 100,000 random samples shows that the vehicle performed better than the targets with a high probability despite the parameter uncertainties. Further, the simulation results using multi-body dynamics simulation software validated the viability of the proposed method.

Adaptive nonlinear damping control of active secondary suspension for hunting stability of high-speed trains

This study employs an active secondary suspension with adaptive nonlinear damping to enhance the hunting stability of high-speed trains. Adjusting passive suspension parameters to optimize ride comfort and hunting stability simultaneously in varied extreme operational conditions poses a significant challenge for high-speed trains. This research integrates high-order displacement-dependent nonlinear damping into the secondary lateral suspension, drawing on insights from field test data. We analyze three typical hunting motion bifurcations: carbody hunting and both subcritical and supercritical bifurcations of bogie hunting. Theoretical analysis demonstrates that (a) the adaptive nonlinear damping narrows the unstable speed range and reduces the amplitude of the limit cycle in carbody hunting, (b) while it does not increase the critical speed for supercritical bogie hunting bifurcation, it substantially reduces the amplitude of the limit cycle, and (c) it increases the nonlinear critical speed for subcritical bogie hunting bifurcation, with the potential to alter the bifurcation from subcritical to supercritical, which holds considerable practical significance. Implementing such nonlinear damping directly through passive structure is challenging. Therefore, in view of this underactuated control problem, the constraint-following control is applied in the active suspension system to inherit the benefits of adaptive nonlinear damping. The simulation results show that the proposed active suspension system can effectively suppress the abnormal vibration caused by hunting motions.

Should sacrouterine plication be added to lateral suspension surgery? A prospective study.

Laparoscopic lateral suspension is a novel approach for repairing anterior and apical pelvic organ prolapse (POP). According to integral theory, urinary symptoms and pelvic pain are believed to originate from suspensory ligaments. We aimed to investigate the objective and subjective outcomes of adding sacroterine plication to apical prolapse surgery. Sixty patients with Grade 2 or higher symptomatic apical POP were included in the study. The study sample was categorized into two groups: Group 1 underwent lateral suspension and Group 2 underwent lateral suspension and sacroterine plication. Anatomical cure was defined separately for the apical and anterior compartments as POP-Q scores for sites C and Ba of less than -1 cm for each compartment. A subjective cure was defined as the absence of bulge symptoms. Patient satisfaction, sexual function, prolapse-related quality of life, voiding dysfunction, nocturia, and constipation were assessed. In Group 1, anatomical cure rates for apical and anterior prolapse were 100% and 70%, respectively (p <0.001). In Group 2, these rates were 100% for apical prolapse and 73.3% for anterior prolapse (p <0.001). The subjective cure was 96.6% in both groups. Furthermore, improvement in sexual and urinary symptoms was more significant in the group that underwent sacroterine plication (p <0.001). The additional sacroterine plication (shortening) procedure with lateral suspension proved to be an effective and successful surgical approach for apical prolapse. Its routine addition to existing lateral suspension surgery can contribute significantly to the improvement of urinary and prolapse symptoms.

A Randomized Clinical Trial Comparing Dubuisson Laparoscopic Lateral Suspension with Laparoscopic Sacropexy for Pelvic Organ Prolapse: Short-Term Results.

Laparoscopic sacrocolpopexy (LSC) is the gold standard for the treatment of apical prolapse, although dissection of the promontory may be challenging. Laparoscopic lateral suspension (LLS) with mesh is an alternative technique for apical repair with similar anatomical and functional outcomes, according to recent studies. The purpose of this study was to compare these operative techniques. Women with uterine Pelvic Organ Prolapse Quantification (POP-Q) stage 2 were enrolled in this prospective study and were randomly allocated to the LLS or LSC group. At the 12-month follow-up, primary measures included both anatomical and functional outcomes. Perioperative parameters and complications were recorded. A total of 93 women were randomized, 48 in the LLS group and 45 in the LSC group, with 2 women lost to follow-up in both groups. LSC anatomic success rates were 81.82% for the apical compartment and 95.22% for the anterior compartment. LLS anatomic success rates for the apical and anterior compartments were 90% and 92.30%, respectively. The mean operative time for LLS was 160.3 min, while for LSC it was 168.3 min. The mean blood loss was 100 mL in both procedures. Conversion to laparotomy was necessary in three women. Mesh erosion was not observed in any of the cases. In terms of the complication, Clavien-Dindo grade 1 was observed in two patients in the LLS group and a complication rated grade 3b was observed in one patient in LSC group. LLS is a good alternative to LSC, with promising anatomical and quality-of-life results.

A complication occurred fourteen days following the laparoscopic correction of pelvic organ prolapse using lateral suspension with mesh

A complication occurred fourteen days following the laparoscopic correction of pelvic organ prolapse using lateral suspension with mesh

A Novel Semi-Spar Floating Wind Turbine Platform Applied for Intermediate Water Depth

For the exploitation of offshore wind resources in areas with intermediate water depths, a novel semi-spar floating foundation is introduced to combine the superiority of the conventional semisubmersible and spar-type floater. It consists of an upper floater and a hanging weight, which are connected through 12 suspension ropes. Such a floating foundation can be wet-towed as a semisubmersible floater, which features a large waterplane moment of inertia to increase stability and reduce transportation costs. After being anchored on site, it behaves as a spar floater with moderate draft and superior hydrodynamic characteristics. The stability of the proposed semi-spar platform during wet towage is analyzed. Afterward, a fully coupled aero-hydro-servo-elastic simulation is conducted to evaluate its hydrodynamic responses in comparison with the responses of the well-acknowledged OC3-spar and OC4-semisubmersible platforms. Then, the ultimate strength of the mooring lines and suspension ropes under extreme conditions was numerically investigated, as well as the relationship between the ropes’ tension and wave direction. Eventually, a cost-effectiveness analysis is conducted in terms of power generation and steel mass. The results demonstrate that the proposed semi-spar design meets the safety criteria in transportation and exhibits a smaller response in surge and pitch motions. In addition, the ultimate strength of mooring lines and suspension ropes satisfies the safety requirements, and simulation reveals that the lateral suspension ropes parallel to the propagation direction are sensitive to the environmental conditions of winds and waves. This study confirms that the newly proposed floating wind turbine exhibits excellent hydrodynamic and power generation performance, which is of great significance for the sustainability of the energy and electricity industry.

Results of the laparoscopic lateral suspension and laparoscopic sacrocolpopexy techniques done for uterine prolapse

Background/Aim: Sacrocolpopexy is considered the gold-standard surgical treatment for patients with symptomatic uterine prolapse. This technique can be performed using a laparoscopic approach. Laparoscopic lateral suspension has emerged as a new alternative pelvic organ prolapse surgery method. This study aims to compare the postoperative anatomical improvement and sexual function outcomes in patients who underwent laparoscopic sacrocolpopexy (Group 1) versus laparoscopic lateral suspension (Group 2) for pelvic organ prolapse at our institution. Methods: Group 1 consisted of 14 patients, while Group 2 comprised seven patients. Relevant data were collected using the Turkish-validated Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12), A Simple Questionnaire to Screen for Sexual Dysfunction, and the Pelvic Organ Prolapse Quantification System (POP-Q) questionnaires. Results: There was no statistically significant difference between Group 1 and Group 2 in terms of the preoperative stage of uterine prolapse (2.6 (0.8) vs. 2.7 (0.7) [P=0.534]). The postoperative period was significantly longer in Group 1 compared to Group 2 (1,014.7 (348.8) days vs. 598.4 (276.5) days [P=0.013]). In the POP-Q evaluation, point C was measured as -6.6 (1.1) cm in Group 1 and -5.2 (1.5) cm in Group 2, indicating a statistically more proximal location (P=0.037). The total vaginal length was greater in Group 1 than in Group 2, but this difference was not statistically significant (8.7 (1.2) cm vs. 8.1 (1.3) cm, [P=0.343]). There was no statistical difference between the groups in terms of uterine prolapse stages and sexual function during the follow-up period. Conclusion: Laparoscopic lateral suspension is an alternative method for patients with uterine prolapse, offering comparable anatomical and sexual outcomes to laparoscopic sacrocolpopexy.

Lateral suspension with v-notes technique (v-nt)

Lateral suspension with v-notes technique (v-nt)

Investigation of a semi-active suspension system for high-speed trains based on magnetorheological isolator with negative stiffness characteristics

As the operation speed of high-speed train increases, trains with fixed suspension stiffness will encounter dramatical vibrations, especially when its lateral resonance occurs. This greatly affects the ride comfort and safety of the trains. Based on this motivation, a novel stiffness variable suspension system using magnetorheological elastomer (MRE) isolator with negative stiffness is proposed. The controllable stiffness can make the train avoid lateral resonance while the negative stiffness characteristics can provide an actuating force similar to the active control, which further improve the vibration attenuation performance of the suspension. The new MRE isolator was firstly fabricated and tested to verify its stiffness variability, especially negative stiffness characteristics. Four different suspension systems were then tested on a 6-DOF vibration platform for the performance comparison. The experimental results show that this new semi-active lateral suspension system has improved vibration attenuation performance than the passive system and the traditional MRE isolation system without negative stiffness. The vibration attenuation performance of the new suspension system is even comparable to that of some of the existing active suspensions while avoiding the disadvantages of the active control.

Transperineal Ultrasound Evaluation of Bladder Parameters in Patients with Apical Prolapse Undergoing Lateral Suspension or Sacropexy.

and hypothesis.We evaluated different bladder parameters using Transperineal Ultrasound (TPUS) in patients with apical pelvic organ prolapse undergoing lateral suspension or sacropexy. We included 73 cases with 37 cases in lateral suspension (LS) group and 36 cases in sacropexy group. We enrolled cases with apical prolapse stage 2 or higher according to Pelvic Organ Prolapse Quantification system (POP-Q). Evaluation done of all cases using TPUS preoperatively and at 6, 12 and 18months follow-up visits. In LS group we found significant differences postoperatively in bladder neck height (Dy distance) at Valsalva and rest (P value < 0.001 in both) and in β angle at Valsalva and rest (P value < 0.001 in both). There was significant improvement in PVR (P value < 0.001). In sacropexy group we found no significant differences postoperatively in bladder neck height at Valsalva (P value 0.07) or in β angle at Valsalva (P value 0.097). There was significant improvement in PVR (P value 0.006). In between the 2 groups, there was better improvement in LS group than sacropexy group in bladder neck height at rest (P value 0.001) and in β angle both at Valsalva and rest (P value < 0.001 & 0.002 respectively). There was no significant difference in PVR, bladder wall thickness or bladder neck funnelling. LS and sacropexy showed good postoperative improvement in somebladder parameters using TPUS with better improvement in bladder neck height in LS. Clinical trial ID: NCT03772691.

A comparative study in learning curves of laparoscopic lateral suspension vs. laparoscopic sacrocolpopexy: preliminary results.

Determination of the learning curve of new techniques is essential to improve safety and efficiency. Limited information is available regarding learning curves of different techniques in laparoscopic pelvic floor surgery. The aim of this study was to compare the learning curve of two operative techniques, laparoscopic lateral suspension (LLS) and laparoscopic sacrocolpopexy (LSC). We conducted a prospective study to assess the learning curve of LLS and LSC by implementing a structured urogynecologic surgical training program with the use of pelvic trainers for our urogynecology fellow. The fellow was an experienced urogynecologic surgeon, but was laparoscopic suturing and dissection naive at the beginning of the study. She was required to assist in 20 laparoscopic urogynecologic surgeries and undertake laparoscopic suturing and knot tying training with mesh positioning on a laparoscopic trainer for 4 h/week during the trial period. After the completion of this structured training program, the fellow performed LLS and LSC under the supervision of an experienced subspecialist as the primary surgeon. Linear regression analysis was used to compare the data of LLS and LSC learning curves. Subjective pre- and post-operative evaluation of pelvic organ prolapse (POP) and pelvic floor disorders was undertaken preoperatively and 12 months postoperatively using the PFDI-20-Quality of Life validated questionnaire. Follow-up was scheduled 12 months after the surgery and performed by a skilled urogynecologist. Objective cure was defined as Pelvic Organ Prolapse-Qualification (POP-Q) stage <II in any compartment. The mean operative times of laparoscopic sacrocolpopexy and lateral suspension were 168.26 and 160.33 min, respectively. According to linear regression analysis after 43 procedures, the learning curve for laparoscopic lateral suspension was shorter than for laparoscopic sacrocolpopexy (OPTime 134.69 min). In both groups, there was a significant reduction in bothersome POP symptoms (p ≤ 0.005). Bladder injuries in two cases and lumbar pain in one case were recorded during the study. Overall objective success at 12 months was 90.7% for LSC and 89.1% for LLS. Laparoscopic lateral suspension could be an alternative to laparoscopic sacrocolpopexy in the treatment of POP with its good objective and subjective outcomes. Lateral suspension has a shorter learning curve, and it is technically less demanding than LSC. Procedure-dedicated training can accelerate the move from a novice to a master laparoscopic surgeon.