Slip Knot Research Articles

A Novel Sliding Knot Technique Without a Knot Pusher for Laparoscopic Pelvic Floor Surgery.

Challenges in intracorporeal knot tying can be addressed with extracorporeal slip knots, simplifying the process of tying and managing tissue tension using a knot pusher. However, existing extracorporeal knot techniques are difficult owing to their complexity, the finesse required with thin yarns, and extensive training needs. We developed a new laparoscopic extracorporeal slip knot technique that can be used with a conventional needle driver or standard clamps, offering the advantages of being cost-effective and easy to learn. The technique involves passing the active strand over another loop and securing it with the nondominant hand. A Kelly clamp is then wound around both loops three times in a tornado-like motion, passing the instrument over the active loop and under the passive one, and grasping the active strand. The passive strand is pulled to approximate the knot to the tissue and is tightened by the tension of the passive strand. This method has proven effective in various laparoscopic procedures such as sacrocolpopexy, colposuspension, pectopexy, myomectomy, and hysterectomy, facilitating surgeries without complications. The tornado knot technique is a feasible and safely locked sliding extracorporeal knot that can be easily learned, especially by surgeons who are accustomed to open surgery.

Comparative strength of ligature points achieved by various surgical knot-tying techniques: an observational study using Maxon™ monofilament sutures.

Surgical knot-tying requires careful selection of the appropriate technique for optimal outcomes; however, evidence is lacking about the common ligation techniques combining square and slip knots (combination knots). This study investigates the strength of a combination knot, compared with other techniques. In this observational cohort study, we assessed the strengths of square, slip-granny, slip-reef, and combination knots using absorbable monofilament sutures, and compared them using ANOVA and a multilevel linear regression analysis. We also assessed the correlation between the number of throws and knot strength using Spearman's correlation analysis. Among 80 ligatures, ANOVA indicated significant differences in knot strength among the techniques (p < 0.01). Multilevel linear regression showed that a combination knot was stronger than a slip knot (p < 0.01) and comparable to a square knot (p = 0.0721). Secondary analysis indicated that for combination knots, five throws could achieve sufficient knot strength. Combination knots are as strong as square knots and stronger than slip knots, and thus present a reasonable option for surgical ligation.

Influence of a single locking throw on the in vitro holding security of five friction throws.

To compare the in vitro security of four different friction throws (square, surgeon's, Miller's, and strangle), with and without a locking throw, and a slip knot, on a vascular ligation model. Experimental study. Nine groups with nine samples per group. Four throws (square, surgeon's, Miller's, and strangle), with and without a locking throw, and a square throw locked in slip knot fashion, were tested to measure leakage pressure. The square and surgeon's throws leaked at a lower pressure than the Miller's and strangle throws (p < .0001). The leakage pressure was below physiologic arterial pressure for the square and the surgeon's throws. After the addition of a locking throw, the five knots leaked at a similar pressure (p = .5233) above physiologic arterial pressure. Following the addition of a locking throw, all the constructs tested in this study leaked at a similar pressure. The leakage pressure for all knots exceeded physiologic arterial pressures. Any throw tested may be appropriate for secure vascular ligation if the initial throw is applied correctly.

Wood defect classification based on lightweight convolutional neural networks

Different types of wood defects correspond to different processing methods. Good classification means can transform defective boards into practical boards after appropriate processing. The detection accuracy of the wood surface defects is particularly important for improving the utilization rate and speed of processing the boards. The RegNet stands out in the field of computer vision. It automatically designs the network model based on the design space and applies it to wood defect detection, which can improve the classification accuracy. When the convolutional structure of the RegNet network is applied to industrial detection and classification, the problems of long real-time detection time and large algorithm parameters persist. This study focuses on collecting wood material images of common coniferous and broad-leaved trees in Northeast China with three types of defects: wormholes, slip knots, and dead knots. To improve the allocation of computing resources, based on the RegNet network model, an attention mechanism module was added, and the Ghostconv structure was introduced. The structure quickly and accurately highlighted the types of wood defects, improved the classification accuracy, reduced the parameters of the network, and exhibited generalization ability. To verify the performance of the improved network, MobileNet-v2, EfficientNet, and Vision-Transformer networks were introduced for comparative analysis. The improved RegNet network had smaller weight and higher accuracy, with a classification accuracy of 96.58%.

Reflecting on the tension between the development of the common law and the doctrine of separation of powers in Paulsen v Slip Knot Investments 777 (Pty) Ltd

This article analyses the adjudicative approaches adopted by the main judgment of Madlanga J and the concurring majority judgment of Moseneke DCJ in Paulsen &amp; another v Slip Knot Investments 777 (Pty) Ltd 2015 (3) SA 479 (CC). The point of divergence between the judgments concerns the discordant relationship between the doctrine of separation of powers and the powers of the courts to develop the common law under s 39(2) of the Constitution. The argument developed in this article is that the developmental powers of the courts should not be curtailed on the basis of a broadly and vaguely conceptualised doctrine of separation of powers, but on a clear and circumscribed doctrine that is congruent with the transformative objectives of s 39(2) of the Constitution. The article endeavours to set out the limited circumstances under which the developmental powers of the courts should be limited in terms of the doctrine of separation of powers.

The Roeder Knot: An Innovative Tool for Laparoscopic Myomectomy

<h3>Study Objective</h3> Demonstrate and describe an innovative Roeder knot technique during a laparoscopic myomectomy. <h3>Design</h3> Stepwise demonstration of the technique with narrated video footage. <h3>Setting</h3> Traditionally myomectomy has been performed via a laparotomy; however, recent advances in minimally invasive surgery have allowed for increased utilization of a laparoscopic approach for myomectomy. Key to a successful myomectomy is control of bleeding and manipulation of a large irregular uterus, both of which are challenging laparoscopically. An absorbable suture can be used to create a Roeder knot, or slip knot, around the base of a fibroid and tensioned during a myomectomy to improve hemostasis, tissue traction, and uterine manipulation. <h3>Patients or Participants</h3> The case depicts a patient with a symptomatic multi-fibroid uterus with a 7cm pedunculated fibroid and a smaller 3cm pedunculated fibroid desiring surgical intervention. Dilute vasopressin was injected under the serosa prophylactically for hemostasis. A suture was secured around the base of both fibroids using a Roeder knot, and the suture secured to the laparoscopic port using a hemostat. The laparoscopic myomectomy was performed with a combination of monopolar and bipolar electrosurgery. <h3>Interventions</h3> This video demonstrates the Roeder knot technique utilizing a 120cm 0-absorbable suture. The technique for tensioning and securing the Roeder knot and application for tissue traction and uterine manipulation are demonstrated. <h3>Measurements and Main Results</h3> The patient underwent an uncomplicated laparoscopic myomectomy with minimal blood loss. <h3>Conclusion</h3> Utilizing the Roeder knot technique to ligate the base of the fibroid during laparoscopic myomectomy facilitates superior hemostasis with improvements in tissue tension and uterine manipulation. Creation and use of this knot is an easily reproducible technique performed at a lower cost than commercial ligating loops. Additionally, the flexible loop size allows for customization to be utilized with larger fibroids.

Knot Types Used by Transformable and Rigid Linear Structural Systems

A knot is the joining place between two or more constructive elements in a framework or structure. They have a fundamental importance in the structure, according to their design they will be able to give a geometric configuration or another to the system and will also absorb certain forces or others. Depending on the movements they allow to the bars, there are rigid knots, articulated knots and slip knots. In this paper a study of cases about rigid knots or embedments used by structural systems so far will be presented. These types of knots prevent the rotation and movement of the constructive elements used for construction. In this paper also a study of cases about the articulated and slip knots used by transformable structural systems so far will be presented. An articulated knot allows the rotation but not the movement of the elements. A slip knot prevents movement in one of the three axes of the reference system, but not in the others, nor in the rotation between the elements. The research is focused in presenting a summary and comparison of rigid knots, articulated knots and slip knots that have been used in the structural design of some architecture. The union systems research will be crucial in this study. The investigation shows an important state of the art that provides technical solutions to apply on novel architectures based on rigid structural systems and articulated and slip structural systems. The research is useful to produce the current constructive solutions based on these constructive systems.

An autopsy study of ligature mark in 634 cases of suicidal hanging

In All Cases of Suspension Deaths, The Study of Ligature Mark form the Important Aspect of External Examination During Autopsy. The Character of Ligature Mark of Self Suspension is not well-defined. To Understand the Characteristic features of Ligature Marks in suicidal Hanging. The parameters studied were gender of victim, Knot Type and Its Position, the ligature mark with reference to its site, level, number, continuity and its Shape. Only Suicidal Hanging were included in the study. In Partial Hanging, The Major Position of the Ligature Mark, in 86% [n-153] cases was across the Thyroid Cartilage and was Nearly Horizontal in the Front. Wheras, In Complete Hanging Majority of the Ligature Mark, 92% [n-420], were situated above the Thyroid Cartilage. In 81% [n-369] of cases of Complete Hanging and 73% [n-130] of Partial Hanging, the Ligature Mark was Incomplete. In 38% [n-68] of Partial Hanging the Ligature Mark was Limited to the Front of the Neck whereas in 13% [n-59] of Complete Hanging it was limited to the Front of Neck. The Petechial Hemorrhages in Ligature Mark due to Complete hanging were Absent. A Slip Knot was used on 97.73% [n-620] of suspensions. In 78% [n-494] of Suspension the Position of the Knot was situated over the [Typical Hanging] Nape of Neck. This Study Highlights the Importance of Characteristic Features of Ligature Mark in Suicidal Hanging, with particular reference to Complete and Incomplete Hanging. The High Number of Cases Studied adds up to the Relevance of the Study.

An autopsy study of suicidal hanging

Hanging is the most preferred method of Suicide. Individuals are known to use different Ligature material and suspend completely or partially. hence, it is important to understand the Parameters involved in it. Large number of Suicidal death are reported. To Understand Suicidal Hanging by studying different parameters involved in it like Ligature Material, Type of Knot. Sex and Age Group, involved, kind of Suspension and Position of knot. A total of 634 cases were studied . Crime scene examination was done only in those cases where their were Suspicion on the Suspension Deaths. Rest of the cases the crime scene photographs and investigating officer records were the inputs. Only Suicidal Hanging were Considered for the Study. Suicidal Hanging contributed to 6.5% of the Total Cases. The Ropes[27%%] and Stole [36%]Contributed to the Most Preferred Ligature Material and Shoe Lace contribute[0.5%] to the least preferred Material for Self Suspension. Complete Suspension was observed in 62% of cases. The Majority of the Victims were Females contributing to 62% of the Deaths. The Major Age Group[50.76%] Involved was between 21-30years and the Uneffected Age group were those in the Extremes of Life i.e 1-10 and 61-70years. A Slip Knot was used on 97.73% of suspensions. In 78% of Suspension the Position of the Knot was situated over the [Typical Hanging]Nape of Neck. Married Victims Contributed to 37.45% of cases. The different Parameters of Suicidal Hanging are necessary to understand the Suicidal Nature of Hanging.

CD38 Genetic Knockout Confers Marked Protection Against In Vivo Myocardial Ischemia/Reperfusion Injury

Background CD38 is a multifunctional membrane protein with the major NAD(P)ase activity in human tissues. It is highly expressed in endothelial cells and some inflammatory cells. Using ex vivo perfused hearts and cell models, we have shown that ischemia/reperfusion (I/R) in the heart leads to CD38 activation with subsequent NAD(P)H depletion and impaired endothelial nitric oxide synthase function, triggering diminished coronary flow and decreased contractile function. Here we test if genetic knockout (KO) of CD38 protects against in vivo myocardial I/R in mice. Methods Male CD38 KO (n=7) and wild type (WT) mice (n=11) in C57BL/6 background were subjected to I/R surgery at the age of 12–16 weeks. The mice were anesthetized, endotracheal intubated, and ventilated with a rodent ventilator. A left lateral thoracotomy was performed, and the left anterior descending coronary artery was visualized and ligated with a slip knot. Then, mice were subjected to 30 minutes of ischemia followed by 24 h of reperfusion. The left ventricular area at risk (AAR) and infarct areas were visualized by Evans blue and TTC staining, respectively. The hearts were sliced and digitally photographed. Left ventricular AAR and infarct area were contoured using Image J software. (P<0.05) was considered significant in statistical testing. Results In CD38 KO and WT mice the AAR/LV % was similar with values of 56.2±6.8 % and 54.6±4.4 %, respectively. However, CD38 KO mice exhibited marked protection against myocardial I/R injury with decreased infarction. Infarct area/AAR was only 10.3±3.2 % in CD38 KO mice compared to 36.7±6.8 % in WT, p=0.0097. Conclusions Thus, abrogation of CD38 expression was observed to be highly protective against in vivo myocardial I/R injury with major reduction in infarction. As new highly potent CD38 inhibitors have recently been developed, these may hold great promise as therapeutics in the treatment of unstable coronary syndromes and acute myocardial infarction.

Self-removal of skin suture using the slip knot technique

Over the last few months, the COVID-19 pandemic has nearly saturated the resources of many health systems, making it essential to reduce the number of patient visits to medical centers and hospitals. After minor surgical procedures, dermatology patients need to return for suture removal. We propose a suture technique that allows a patient to remove the stitches at home with 1 hand, using medical gloves. It is recommended for punch biopsies or small skin excisions.

Abdominal infectious complications associated with the dislocation of intraperitoneal part of drainage tube and poor drainage after major surgeries.

Abdominal drainage, serving as a diagnostic and therapeutic tool, has been widely applied to prevent complications after major abdominal surgical procedures. However, dislocation of intraperitoneal portion of drainage tube and poor drainage after major surgery has never been detailed. In this retrospective study, we determined whether postoperative abdominal infectious complications are attributed to dislocation of intraperitoneal portion of drainage tube. Patients were recruited from the Department of General Surgery at Beijing Shijitan Hospital, Capital Medical University, between June 2015 and June 2018. All of the enrolled patients had undergone different major abdominal surgical procedures with abdominal drainage. According to different fixation methods of the drainage tube, the patients were categorised as follows: group 1 as conventional extra-abdominal fixation where the tubes were fixed on abdominal wall; group 2 as double fixation where the tubes were fixed by both extra-abdominal and intra-abdominal fixation. Among 60 patients (40 in group 1 and 20 in group 2) with suspected postoperative abdominal infection, abdominal computed tomography (CT) was performed to determine the presence of abnormality. Dislocation of drainage tubes, morbidity, treatment, and prognosis were compared between the two groups. None of the patients showed slip knot or drainage tube slipping from the abdomen based on physical examination and CT imaging. Drainage tube was fixed firmly on the abdominal wall. In group 1, 18 (45%) patients developed postoperative complications resulting from abdominal infection where severe dislocation of intraperitoneal portion of drainage tubes was confirmed by CT. Drainage tubes of six cases were significantly dislocated to the anterior abdominal wall from the target area; 7 upper abdominal drainage tubes dislocated to the lower abdomen; and 5 lower abdominal drainage tubes dislocated to the upper abdomen. Common complications included localised peritonitis (n = 4), abdominal abscess (n = 8), and anastomotic leakage (n = 6). Among them, 8 patients were cured by abdominal puncture catheter drainage; 5 underwent secondary operation and 5 were cured by conservative treatment. In group 2, no tube dislocation was identified by CT. Five patients (25%) developed complications, including localised peritonitis (n = 1), abdominal abscess (n = 1), and anastomotic leakage (n = 3). All the five patients were cured by conservative treatment. Postoperative abdominal infection complications can stem from dislocation of intraperitoneal portion of drainage tube and poor drainage after major abdominal surgery. Maintaining the intraperitoneal portion of drainage tube at the proper location, for example, by applying intraabdominal fixation, is paramount to decrease the incidence and severity of postoperative complications.

Classical but Not Rap Music Significantly Improves Transferability and Long-Term Acquisition of Laparoscopic Suturing Skills: A Randomized Controlled Trial.

Acoustic distractions have been shown to increase the level of stress and workload in the operating room (OR). Noise significantly reduces surgical performance, but experienced surgeons are able to reduce the acoustic perception of their surroundings to maintain a high level of performance in complex surgical tasks. However, music has been shown to improve learning and performance of complex motor skills. The aim of this study was to evaluate the influence of music on transferability and long-term acquisition of laparoscopic suturing skills. To evaluate the effects of music on training, subjects were asked to perform four surgeon's square knots on a bowel model within 30 minutes-prior and post 3 hours of hands-on training. To examine long-term skills, the same students were asked to perform a comparable, but more complex, task (four slip knots in a model of esophageal atresia) 6 months post initial training, as a follow-up measurement. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan scale), and laparoscopic performance (Munz checklist) were assessed. Twenty-four students were included in the study; after simple randomization, 16 were trained while exposed to music (eight to Bach and eight to Bushido) and eight with traditional methods. Seven were lost due to follow-up. Both groups had comparable baseline characteristics and significantly improved after training, in all parameters assessed in this study. Subjects that trained with classical music were superior in terms of speed (p = 0.006), knot quality (p = 0.014), and procedural performance (p = 0.034) compared with controls. Music during acquisition of complex motor skills, like laparoscopic suturing and knot tying, is superior to traditional training. Especially music considered nondisturbing significantly improved speed, knot quality, and performance. Thus, incorporation of pleasant music into surgical skills training and the OR should be considered.

Use of Laparoscopic Slip Knot with Purse-String Suture in Surgical Management of Unruptured Heterotopic Interstitial Pregnancies.

BackgroundThe aim of this study was to investigate the advantages and disadvantages of using laparoscopic slip knot with purse-string suture technique in the surgical management of unruptured heterotopic interstitial pregnancies compared with other surgical strategies.Material/MethodsWe retrospectively analyzed data on 13 patients with unruptured heterotopic interstitial pregnancies who underwent laparoscopy in our hospital between May 2012 and August 2018. The control group consisted of 10 patients who underwent cornual resection or cornuostomy with conventional sutures and knots. The study group consisted of 3 patients whose surgical plans involved use of the slip knot with purse-string suture technique followed by cornuostomy. We evaluated the surgical records and video to comparatively analyze their operation duration, intraoperative blood loss, and pregnancy outcomes.ResultsThe average volume of intraoperative blood loss was 76.67±25 ml in the study group and 215.00±110 ml in the control group. On average, the intraoperative blood loss volume in the study group was 138 ml less than in the control group and the difference was statistically significant (P<0.05). There was no statistically significant difference in the live birth rate and operation time between the 2 groups (P>0.05). The duration of hemostasis in the study group was 11 min shorter than in the control group, while the duration of cornual electrocoagulation in the study group was 18.5 s shorter. Both groups achieved thorough hemostasis without the help of vasopressin and avoided use of embryo-killing drugs such as methotrexate. Neither group required second surgery or developed postoperative complications such as uterus rupture or persistent ectopic pregnancy.ConclusionsThis strategy is safe and reliable for gestational sac clearance while simultaneously preventing any potential harm to the intrauterine embryo. It is particularly suitable for unruptured HIP patients who have a strong desire to preserve their intrauterine embryos.

2758 Easy-to-Master Slipknot

Video Objective In laparoscopic intracorporal knot tying, we have to ligate securely in the limited space. The slip knot technique is useful in these situations. I will show the key and logic of slip knot using a two-color suture, and some techniques. Setting The procedures to perform slip knot are as following: Firstly, you make a square knot by two opposite half knots consisted of one clockwise and the other counter-clockwise. Then, you can push and slide the “unlocked” square knot toward the ligation point and secure the tissues. “Unlocked” means the state of which the square knot is slidable, and keeping this state is the secret of slip knot. A two-color suture is helpful to understand this state. Various slip knot techniques are below: 1) Standard slip knot. This is the basic way, an unlocked square knot is slid to the ligation point. 2) Loose one-hand slip knot. As a square knot is unlocked and loose, you can tie the knot by pulling the long tail one-handed. 3) In case of the locked knot. You should pull the long tail and release the knot before you slide it. 4) Pulling the short tail. You can also tie the knot by pulling short tail in theory. 5) Knot tying combined with surgeon's knot. You can alter the first opposite half knot to double half knot. To get your slip knot more smoothly and quickly, you should manage the suture near the knot, omit the time and effort for catching the suture of second opposite half knot. And training never cheats on you. Interventions N/A Conclusion These techniques can help your operation get better definitely.

Simple and safe thoracoscopic repair of neonatal congenital diaphragmatic hernia by a new modified knot-tying technique.

Clinical outcomes in infants with congenital diaphragmatic hernia (CDH) may be improved by thoracoscopic repair. However, the limited domain and large diaphragmatic defects in neonates are obstacles. Here, we present a special knot-tying technique that facilitates a safe and efficient thoracoscopic CDH repair in neonates. An extracorporeal slip knot is assembled after a stitch through the diaphragmatic edge, one end of the string is pulled, and the knot slides to reach the diaphragm easily without a knot-pusher. Then two more uncomplicated single-loop knots are performed to secure its tightness intrathoracically. Twenty-six consecutive neonates with CDH were treated by this technique. The technical advantages and clinical outcomes were evaluated. All 26 patients were treated successfully, including 6 patch-repairs and 1 case with associated extra-lobar pulmonary sequestration. The mean operative times with and without patch-repair were 149 ± 26min and 95 ± 25min, respectively. All cases were completed without conversion. No recurrence was observed at a median follow-up of 13.7months (range 5.8-29.8months). This special knot-tying technique is easy to learn and does not require any additional devices. It is a simple and accessible technique that can facilitate thoracoscopic repair of neonatal CDH within the limited space and with patch-repair.

Spaced Education Improves the Retention of Laparoscopic Suturing Skills: A Randomized Controlled Study.

Spaced learning has been shown to be superior in complex motor skill acquisition like laparoscopic suturing and knot tying. By using a pre-post follow-up design, the aim of the study was to evaluate the long-term impact of implementation of the spaced learning concept in laparoscopic training. To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon's square knots on a bowel model within 30 minutes-prior and after 3 hours of hands-on training. To examine the long-term skills, the same students were asked to perform a comparable, but more complex, task (four slip knots in a model of esophageal atresia) 12 months later as follow-up measurement. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan scale), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation. Twenty students were included in the study; after simple randomization, 10 were trained using the "spaced learning" concept and 10 via traditional methods. Both groups had comparable baseline characteristics and improved after training significantly, regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of speed (p = 0.021), knot quality (p = 0.008), and suture strength (p = 0.003). Additionally, spaced learning significantly decreased anxiety (p = 0.029) and probability of success (p = 0.005). The spaced learning concept is very suitable for long-term complex motor skill acquisition, like laparoscopic suturing and knot tying. It is superior to conventional training regarding speed and, most importantly, knot quality and stability, resulting in improved confidence and motivation. Thus, we strongly recommend to incorporate the spaced learning concept into training courses and surgical programs.

266 - The Basics of Laparoscopic Myomectomy

The Basics of Laparoscopic Myomectomy is a surgical education video that presents safe and efficacious techniques for laparoscopic myomectomy. Special emphasis is on hemostasis (tourniquet, vasopressin), fibroid enucleation, repair and minimizing adhesion formation. It demonstrates Roeder slip knot, intracorporeal knot tying, multilayer closure and baseball stich. Cold knife bagged extraction is presented at the end that allows for safe removal of even the largest specimen through a cosmetic incision.

How to demarcate intersegmental plane with resected-segments inflation method using the slip knot technique in thoracoscopic anatomic segmentectomy.

Intersegmental demarcation line on the surface of the visceral pleura could not be found at thoracoscopic findings. The resected segments inflation (RSI) method has been reported as a useful technique for visualizing the intersegmental demarcation line during segmentectomy. Thoracoscopic anatomic segmentectomy is performed as follows: firstly, the pulmonary vein and artery of the segment planned for resection are dissected from the hilum in order to isolate the segmental bronchus located behind the pulmonary artery. Secondly, a monofilament non-absorbable suture is passed through the segmental bronchus, and a slip-knot is made outside the thorax. Thirdly, bilateral lung ventilation with pure oxygen is conducted. When the affected segment has inflated sufficiently, the slip knot suture is pulled and the segmental bronchus is ligated and collapse of the lung is made on reserved segments. Fourthly, as inflation of the affected segment and collapse of the reserved segments could be found, resection of intersegmental plane could be easily performed with the inflation-deflation line and the intersegmental pulmonary vein. If resected segmental bronchus could be identified, thoracoscopic segmentectomy with the slip-knot technique would be applicable. This slip-knot procedure is economical and is not need special instrument.

How to make the slip knot

How to make the slip knot