This on-demand teaching session is relevant to medical professionals and offers an in-depth look at surgical knot-tying techniques. Participants will learn the nuanced techniques and physics behind knot-tying and how to tie knots with both hands, such as the Figure 8 Pull through knot and the reef knot. Candidates from 11 countries all over the world can join the session to learn the basics, aided by the soon-to-launch Black Belt Academy app, along with the opportunity to ask questions in the chatroom. This is a great learning opportunity to hone their surgical skills in a unique setting.
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Knot tying does not come automatically. It does require lots of practice, initially with a piece of string. In the beginning it appears a mystical art with a lot of confusing parts. However, once the principles are understood, the operator will be able to ties knots with both hands and use the finest of material. Good secure knots are essential for surgery and failure to secure a knot can be catastrophic.

Learning objectives

Learning Objectives: 1. Understand the history and development of knots and their mathematical and scientific connections. 2. Learn how to accurately tie a "figure of eight pull through knot" and identify its benefits. 3. Gain knowledge of the AGLET, its inventor, and its historical importance. 4. Understand the differences between a square knot/flat knot and a granny knot and recognize why certain knots are more effective. 5. Develop the confidence to confidently tie knots using both hands.
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The following transcript was generated automatically from the content and has not been checked or corrected manually.

Hello. Good evening. Good day. Good afternoon. Wherever you are in the world and welcome to the Black Belt Academy of Surgical Skills. My name is David Regan. I am a retired cardiac surgeon in Yorkshire in the United Kingdom. The immediate past director of the Faculty of Surgical Printers of the Royal College of Surgeons of Edinburgh and a visiting professor at Imperial College, London. Our venue has changed because I saw the house and my wife and I are moving, but because we've got two dogs and we booking Globe didn't want to commit ourselves to a house immediately. So what we have done is we have bought a secondhand caravan uh used from running holiday park caravan site. Earlier today I set up outside in part of the pitch because it looked sunny and bright. Indeed. The weather fraud cast told me it was going to be sunny and bright. But as we approached seven o'clock, the clouds looked a bit more ominous and it started to drizzle. This was not on the weather forecast, but I looked at the clouds getting darker, checked it at the forecast and they said nothing was going to happen on the country, what actually happened, the skies opened. But I had moved everything inside and you're perceived that I'm under canvas and if you listen carefully, they're tweeting birds outside, what is proven is no matter where you are or what you're doing, it is possible to practice your surgical skills. The other important thing is that as Professor Magdi Yacoub said to me many years ago, cardiac surgeons do not panic. So when the heavens opened and hail came down, I moved everything inside and set up. The one thing I cannot mitigate for which will have to test and try in due course is heavy rain on canvas because the noise would be definite. I'll switch to Lapel mic but in the meantime, keep the yeti microphone on the side and I hope you enjoy the ambient noise in the background of the birds tweeting on an early spring evening in North Yorkshire in the United Kingdom. So there you are. That's my story. But I'd like to thank the 3300 people on Facebook and the 594 followers on Instagram. Thank you very much. And if this is your first time joining us? Welcome. Understand we have candidates from 11 countries this evening and the reason we go live, it's to enable you to ask questions in the chat room. And Gabriel who's kindly doing the producing in the backstage will answer them. They are the exciting news is we're about to actually launch our app. Well, it's in the final stages of testing and we hope to put on the app some self assessment exercises that you will recognize that we have discussed and demonstrated on the Black Belt Academy where I recently met with Doctor Chen Quinn at Imperial College Artificial Intelligence and Data and Computer Faculty. And we have seconded Pelham from Cornell University who's going to look at extracting data from the banana stitching such that you can point your mobile phone, take a picture and we'll give you a score and recommend how to improve your station. So exciting times ahead this evening, we're going to talk about knots when you think about it, not have been intrinsic to society and the way we live ever since the stone age, so fasting garments, time material together in the Babylonian Times, recording information in medieval times for decoration and lots of even had spiritual and religious significance. The Celtic knot adorns the book of Nell's every page. And when they got indicative of wedlock, the mythical Gordian knot set up by a disheartening king in mythological Greek times was such that nobody could undo it. But a wondering soldier walked into the square saw the not and took his sword to it and rendered it asunder. It was said that personally undid them not will run and rule the lands of grease. And that young soldier happened to be Alexander the great. But there is a mathematics behind knots. And every time or not you weaken the threat. And the best not to tie is a figure of eight pull through. Not which even on pool and stretch tests only weaken it 75% but most not will actually weaken the thread. And that's where it will break. There's a mass behind this and a lot of study with the breaking and the tension of knots. But back in 18 33 a Carl Frederick gas put a computing number to this. And his student listing gave his name to a particular not from physics point of view. Thompson was watching the famous Scott physicist Peter Tate and wondered whether atoms were ready swirling knots in the ether. And he came up with a list of a lot of different knots to try and explain the chemical element table. I suppose thinking about it. If he thought of atoms as swirling knots in the ether, that's not too far off spinning theory, we're doing this to me string. And that's all you need. In fact, was Maxwell who looked at gasses mathematical works and deduced that there's probably an electromagnetic theory behind all of this. So not go a long way. So basically what is a knot? You have a piece of string with two hands, you cross the murmur and one end is going to go through the other two form or not. And as we teach the one handed surgical, not we create a loop with the short end and the long hand and our finger has got a flick the short end through the loop and you catch it between fingers and take it away. Let me show that to you again because it's the nuance of tying the knot that is poorly explained or demonstrated. As you watch people dramatically tie knots thinking the faster you Thailand the better. No, is the answer the fast you Thailand, the more likely they are to be inaccurate and the more likely you're going to actually damage the threat. I remember Mr West be asking the sister to actually squirt water on the strings because yes, time or not so fast the friction and the heat was there wrong. Please don't do that. So you have two ends of string, you cross them over and you flick the short end through and you catch it between your fingers and take it away and reapply with a finger and thumb. So I'm going to do that slowly, both right hand and I'm going to adjust the camera and bring you down to level that. I hope that you can see what I'm doing. So it's always best to start with a piece of string or shoelace. I like the shoelace because on the end, there's this little thing called the AG let now the AGL it was patented the Harvey Kennedy in 17 90. This was an extension of all those decorations for many years. People put on the end of laces to stop it, Frey but this plastic agl it raised in excess of 1.8 million lbs in 17 90 can who patent today. So let's take it from there. Simple things count so short end, long hand, okay. What I'm going to do is finger and thumb, just turn around. So for the camera short end, long end with the short end, I'm going to prone eight, my hand to hold it out with the ag let being held between my finger and thumb, I'm going to cross the long over the short. The long is crossed over the short and that's where they cross it. Now, you see between the long and the short, there's that little bed between the upright and my index finger and thumb and that's the shorthand that you flick. There you go, flick through the hole and I've caught it and I'm taking it away and I'm taking it down. All right now, I'm actually holding between my middle finger and some. So I'm gonna sweep out, turn in and I'm holding that short end out again. I'm going to cross the long over the short. You can see as previously, I've got an inverted figure of four. My index finger now is gonna flip around there and flick it through. OK. My index finger is gonna flicker it through and I'm going to catch it. There you go and bring it towards me like that. My hands moved one way and then the other way they didn't cross over and are moving one way or the other way. I hope you appreciate that we now have on there. Very good reef. Not. And this is important because the reef not is a square, not right over, left, left over, right. And if I put my fingers in that and I'm tying this, pulling it tight, pulling it tight like this. All right. There you go, itself tightens. It doesn't come undone. And this is called a square knot or flat not. You see it sits flat on my hand. All right. And that's what we need to be doing when the tie knots is tying flat. Not like this. By contrast, this is a, this is called uncrossed. Okay. And this is a cross not across or granny knot and across the granny knot doesn't sit flat on the top, okay. It does not sit flat at all. And the important thing with this not is that if I put my fingers in it and I work it, work at work at work, at work, at work it, there you go. It comes undone. And that is the simple reason why your shoelaces come undone with walking throughout the day. And you can tell the difference between a good not and across, not of your shoelaces by whether the laces themselves sit across the shoe or down the shoe. If they sit down the chute you have actually got a crossed not that'll come undone. So let's go through that one more time and then we'll go together to the chemistry. You can use any bit of elastic band sitting on a book, anything, a couple of pencils to create, you're not time station. You do not need these purpose. Basics, bespoke things support. So you start with a short end finger and thumb, shortened finger and thumb. I'm gonna super Nate and hold it out. Cross the lung. Oh The short, my middle finger is going to flick. That's true. And I'm carrying it away, holding it between my middle and my thumb. Now I'm going to put my finger down there to bed the not down because this is the next principle we'll address in a moment. Finger enough sweeps out back in and I'm holding it out boxing the long as the short and I got a flick that short through that whole and bring it towards me. And there you go a flat. Not once you get going and understand that your hands are doing, that's for the movement. It becomes automatic and it's important that you learn to tie your notes with both hands. So fingers and thumb, left hand super need out cross it over. Now my middle finger has got to flick it through. You see there you go flick it through and I'm catching it and I'm taking it away, putting my finger on the water, you're gonna sweep that out. Turn it in, hold it out. Cross the long over the short and my back of my index finger has got a click is awkward because it's sometimes to that then flick it through. Catch it. There you go, catch it, bring it away and now I'm holding it. Yeah. A note that my fingers throws have alternated between index finger, middle finger and that I'm flicking it through with it, that finger or that finger. All right. And my hands are doing this. So that's an elaborate sort of we've so to speak because your hands are doing that and these fingers are doing this as well. Let's try it again with my left hand short end long and super neat. And you're gonna flick that, flick it through, catch it between ring and middle and take it away, holding it the agl it between the middle and thumb. I'm sweeping my finger out. There you go across the longer the short, flick it through and catch it. They go and take it down and there you have yet again. Very nice. Flat. Not, well, that's all well and good. And that's the first part that you need to practice actually withholding the strength. But then the next Procrit is, is you can appreciate, we're moving your hands like that. There's a propensity to pull it off what you're trying to tie. So it's important when you're tying something down that you're pulling across the not, and your finger is pressing down across the, not to stop the whole thing being displaced. So there's a very nice little exercise that I like to have introduced to the Black Mamba Academy for this element of what I call putting down. And I take a coat hanger on the table and a plastic coating and that because it's important that you are able to secure, you're not on a solid surface. Now, I'm going to bring this down again at an angle for you to see short end, long end. I'm going to throw one through, take it away and I go through again the same direction. So what I end up with is a slip not to half fetches like that because now you can see when I press down, I am tightening this not so my finger is across the not and I'm pressing my finger into the table, but you can see the coat hanger is not being lifted off. I now can complete right first and secured it, turning it down. And I'm trying to actually do this, minimizing the movement that I'm making on a coat hanger. Now, it's an awfully awkward exercise. But supposed to be because if your morals, our practice so easy, will you get to do the real thing? You'll run into trouble. So these give you feedback. So to test where they bend it down, I can see if I can slide it across okay and only with a bit of encouragement. Now, I can start meddling across, but that is the next part of teaching you to tie and bed down. So let's do that again. The short end had a long end came through, same through each direction. So it's got two half hitches. All right. So that enables me to actually slide it down and bed. They're not down. And I'm putting the school with the tension of my forearm. Remembering that as you tied, it's possible to strangulate the tissues as well. And what you need to be able to do is approximate. So there you go. Now, it's another little fun thing you can try and do when you're learning. Not because how short can you go to flick these through? And I'm probably at my limit there, I can probably get one through. There you go and down. So it's a nice little fun game you can have with yourself is how short can you get that end to tie down any surface? But using a bit of plastic is useful, underst useful to use different materials. So once you have understood what you're doing with a piece of string, try cotton, cotton is rather nice because it's again unforgiving and breaks if you put too much pressure on it, okay, let's have a go. The same principle is applies all the time. It's the weight of my finger on the not now that is actually betting it down too often. You see people time the knots and you hear the string rasping down, but that's fray breaking. There you go, can grab it and it doesn't move across the surface. But we're not tying on the surface frequently. You're tying at depth and I've just got a bit of piping here. They're, now I'm gonna try tying at depth. All right. And this is what we do all the time of surgery is tired. Depth show on another occasion, the secret to passing a thread around using a leahy or Roberts and bolstering the thread across the curve, passing tip beyond where you're going and then you can pick it up. So you don't have to do that little nonsense I'm doing here. There you go. See him again. This time you're at depth. But now you've got an angle, your finger down into that hole and practice doing that. The same principles apply that you maintain a finger on or not to ensure the knot is buried out. That's an easy way of getting you to extend your fingers. Uh, I'm moving my hands like that, but it's a lot more subtle, a depth that's cut. So we look, oh, I'm gonna fail myself there because you see it's moving and if that's the case, sorry, but try again because it's important that you're not, are bedded down and do not slip at all, not slipping in surgery as you can appreciate is catastrophic. And if it's a mono filament, which is a bit of plastic that's drawn out into a long string, not comes undone, the whole sertraline itself will come and done. So, the thing about doing it, life is demonstrating that I to sometimes have difficulty with these models because they're supposed to be difficult. Yeah. Yes. Thank you. Take that off. Now, I'm satisfied that's not going to move. What we do use in surgery though is per line and this is quite a thick Perlin. Uh, but you don't have to get any from theater. The best thing to use is a bit of fishing line. I'm going to change this fishing line because it's clear and you can't see it. But for practice purposes, any fishing line will do the blue fishing line here, however, will give me visibility that I require for this exercise. Yeah, it's important that it's better down. How many throws do you put on it? Well, this is moving around and I'm sure my fellow since they will say, oh, you didn't square that last note. And you're probably right why I'm putting at least seven throws. All right, thick monofilament as you see here. But I'm doing this also to demonstrate this now as a mono filament has given me yes, spike tissue. And if I cut that and if that was an end of a deep suture, closing tissue layers, that spike that can work its way out through the skin. And if it's on a dependent surface will cause a lot of discomfort and potential damage and a sinus and later infection. So, the important thing is when tying amount of filament for dick tissues, please bury the not on the inside. That means coming from inside, out, outside, in and tying it underneath. So they're not sits within deep tissues and not protrusion on the skin. Something to bear in mind all the time. How many throws I put in seven for a monofilament and five for a braided future. Like it's like a vehicle or a silk, although silk is not used any longer. So once we've got to that sort of level of tying or not, obviously, we need to actually know is, are not time secure. And I like this exercise because it literally tells then and there, if you're not tying is secure, we got a balloon. I just put a just so, you know, I'm not cheating. There you go. And we're gonna tie off the neck. It moves around the balloon. So it makes it very important that you control, you're not and you control your time now and my finger is on the not okay. Yeah, finger is on the, not when putting an aortic valve in. We have between 21 28 sutures sometimes more if they are simple interrupted sutures. But it's important that the operator ties the knots diligently each time. So when standing opposite the trainee, I used to say to them tie the knot. And what they needed to do is say, finger on the nod when it was battered down. And if they finger stayed on the, not for the duration of them saying finger on the, not, I'd say one and then they do the next throw finger or not. And I'd say two finger or not and I'd say three until we get to five. Sometimes we will reverse it. They'd say one, I'd say finger on the not. So let's have a look. There you go. Cotton time that we learn. Now, is it exercise of not time? This is taking you to the next level because the cotton itself would break. If you put too much pressure on it, this moves around a lot. And if you don't get it down, this would leak clearly. And by bending it down, you've gathered the tissue uh fantastic. You might say, uh there you try it again because we have demonstrated that works on telly justice, repeat the exercise and go through. Now, I'm predominantly a right handed, not tire, unfortunately. And I wish in the very beginning that I was cajoled, persuaded to tie you both. Not oopsie, that's come undone. You see that just like that it's coming done. I'm gonna have to take that off again and try that one more time. So that's the thing. I've got a uh injury to my wrist left and I am not as comfortable tying knots, particularly final searchers give my left hand and I wish somebody in the very beginning had said to me, please. Whoops. It's done it again, hasn't it? There you go. This is now, uh huh. The important thing is that often said, doing these things live is not staged. You also see that experts have problems with some of these exercises and I had pulled them out too tight now, have a broke and persevering because I think it's a good model and I'm getting good feedback from the model in doing this and learning each time. Mhm. Mm. Oh. Is he feeling quite strong today? That's, uh, and they have it interrupted sutures traditionally, sorry to give it to interrupt. Uh, there wasn't any connection for the last couple of minutes, so we haven't seen what happened, but it's all. Yeah. Oh, I don't know. Let's try again. Shall we apologize for that? Um, I'm not on my B T internet fiber optic at, uh, so what you're saying is, take a short end, short end. Yeah. Take the suture twice as the instrument doing that, pulling it down flat and then locking it by crossing it over that holds it in place. And now I'm going to alternate my throws across the instrument and it's important in the same way if we actually talked about flat knots that you look as you move your instrument true one way flat the other way flat. So you're doing that again. But with an instrument rather than your hands to ensure that you've got flat knots and secure knots. So there's a lot of exercises there for you to practice at home. And I'm doing this in the caravan in the Holiday Park. And if I can actually deliver basic surgical skills lesson in this, sent it my challenge to you is why can't you practice at home? Okay, because you don't practice until you get it right, you practice until you can't give it wrong. And the bottles that we introduced Black Belt Academy of Surgical Skills as you've seen this evening are there to show you if it gets it wrong and what we know from learning. If you learn more from failure and success, enjoy the models. Enjoy your practice. I hope you like the location. I hope the birds have kept you entertained in the background. They seem to be getting light louder this time and when the weather is good, we will be outside. Please join me next week as we get to look at forceps skills and how to practice those at home. And these will be part of the earth that we're developing. And I'm going to forage around the grounds for natural things fast to practice on. And I took particular interest in the dandelions that are now coming up. See you next week. Be well, be safe. Thank you for joining the Black Part Academy. Thank you Gabrielle for the production in the background and thank you for joining us.