This on-demand teaching session aims to provide medical professionals with the knowledge and principles for proper surgical suturing techniques. Led by retired cardiac surgeon Dr. David Regan, the audience will learn about the types of sutures available, the differences between each one, and how they can be used appropriately from suturing bone, tissue, and the abdominal wall to repairing hernias. Plus, Dr. Regan will be doing an in-depth demonstration of suturing techniques with a pork belly and discussing the benefits of various materials and knots. Join this session to get everything you need to master the art of suturing.
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BBASS rounds up the series on stitching talking how we bring tissues layers together. The principles of stitching apply to continuous stitches and the tension of the suture is of utmost importance. BBASS will also discuss when and where to use drains. Finally we will address how to close the skin and talk about dressings.

Learning objectives

Learning Objectives 1. Understand principles of suturing and closure of tissue. 2. Describe different kinds of non-absorbable sutures and their use in various procedures. 3. Know the importance of respecting anatomical relationships, blood supply and tension when suturing. 4. Analyze the impact of monofilament and braided sutures on a surgical environment. 5. Demonstrate an effective technique for suturing and tying knots in muscle and fascia.
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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 morning, wherever you are in the world and welcome to the Black Belt Academy of Surgical Skills. My name is David Regan. I'm a retired cardiac surgeon in Yorkshire in the United Kingdom. The past doctor are the faculty of surgical Trainers from the Royal College of Surgeons of Edinburgh and a visiting professor at Imperial College, London. And we truly grateful to you, the followers of the Black Belt Academy. Were you reaching 55 countries? And any one evening, we can have 18 countries represented I conscious I in your part of the world and very grateful that you've joined us. Thank you to, to the 4230 followers on Facebook and all the followers on Instagram. This week, I want to bring to a close our series about suturing and bringing it to the close. I'm reminded that in theater, everybody thinks the operations done when the anastomosis is finished or the organs removed or implanted, but you have to get out, you have to close all the tissues behind you and often that is left to the most junior less and it is usually done without attention to detail. And without an understanding of exactly what we are doing, closure requires an understanding of principles which we'll outline this evening and an understanding of suture material. Now, I'm going to skirt over some of the suture material because there are some detailed information online that you can look up. In essence, when we close having entered a body cavity or gone down to a bone, we need to think of form and function. We need to respect the anatomical relationships and planes and think that all these planes slide over each other. And that's why they have to be approximated carefully each and every layer in doing. So, we need to think of the b blood because poor blood supply is not going to heal. And if there's infection that will be problematic too, we need to think of the tension that we are putting on the tissues, especially as many patients who are anesthetized, they wake up the tensions in the muscles and the abdominal wall increases. We also then need to think about spaces and potential space, spaces, collection or collections of fluid, the movement of your needle through the tissue of the pickup of the needle. 123, we've talked before and place point rotate is important, specifically doing a continuous suture. I have often have people doing a continuous suture, lose the pick up of the needle and they focus more on the action of going through the tissues rather than placing them and gently opposing them. The problem is with a continuous suture. I often see people do 1234 stitches, pull the right pieces, all the tissues out. In essence, you know, the two differences between the sutures. The monofilament, which is really a stretched out bit of plastic like material is waterproof. It has low reactivity, it glides through the tissues easily but it's easily damaged and the knots are bigger because it is in a monofilament. The braided searches are easier to handle. They are more comfortable but they drag through the tissues despite being coated. And the braids actually result in a capillary action of fluid through the tissue carrying bacteria and also stimulating an inflammatory action and in increasing the prospect of scarring. Very simply if you look at braided suture and I'll go want to focus on that. If we look at a brad suture, that's a vir that sits flat. It's only five throws that is a P DS there. And you can see that is spiky. Now, even if you put that in deep tissues that spiky bit, especially in pressure areas will cause discomfort and may, even if a patient loses weight protrude from the skin. So when choosing the suture and it's the surgical preference, whether you use a monofilament or a branded suture, you must bear in mind that not and they're not will cause problems, especially on pressure areas. Now, we all think that nylon here which is cheap, usually black or clear is a permanent suture. It is not, there is a degradation of 10 to 15% in tensile strength per year. It is low friction, low cost and it is very strong. It can be used for the abdominal wall and finer sutures used in ophthalmic surgery. The thickness of a suture determines the tensile strength and the common suture zero sits at approximately 0.35 millimeters. Two drops, 0.4 millimeters to a diameter. 0.30 30 drops at 0.1 of a millimeter to a diameter of 0.2 and four drops, another 0.5 to 0.5 and it drops to 50 to 0.1 and it drops again by 003 to 0.07 for 60 s. You get the picture, the more zeros, the six zeros, the 708 zeros, nine zeros and the microsurgery 12 zeros thinner and thinner. The properties are the same, but because of the thickness tensile strength disappears at time. So when we think about our strength, we want to think about the function of the tissue and the load or the strength that it needs to actually include and the tissue that is always there. And as popular with cardio since is pru it's blue or clear, it lasts forever. The problem is as you see with all mono filaments has got a memory but it is lotion. On the other hand, stretching it damages it and grabbing it with forceps would damage it as well. However, it's popular with cardiac surgeons, vascular surgeons and useful for the skin provided you take it out. In essence, the non-absorbable sutures need to be deeper in the body. Such they don't extrude. If they're on the skin, you take them out, but the deeper the tissue more likely you need something is nonabsorbable. Um The thicker the suture, of course, the permanent suture that's braided effy bond. Uh ei bod is a polyta. It's a nonabsorbable braided suture. It behave like a braided suture. It laugh forever. But because it's braided, it will scar non absorbable sutures. They also include wire. The wire is very useful in cardiac surgery when we wire the sternum together. But the wire and like monofilament can choose wire out of the tissue. And therefore sometimes I've used an effi bod to pull the sternum together. But these also end up with big bulky knots. They found that the knots particularly in thin people were truant on the sternal wound. So, non-absorbable sutures, are you closing, bone, approximating ribs, repairing tins, bringing strong pressure together. And they have been used with clothing, dima repairs, hiatus, hernias and also new repairs like the should ice repair. That was popularized for hernia repair used a fine wire. It is there for strength and is not to be removed. The one filament is nonreactive as the bladed filament does cause a local inflammatory response. So let's go over tomorrow and we can talk about these different sutures and what we're going to do with them and how are we going to use them? Because that determines the stitching and the decisions on the system. When I started, we used cat and chromic C that was covered to with chromic sulfate to reduce the enzyme reaction and degradation of the cat gut. But cat gut is banned in the UK and Japan because of BS E. We also used silk. And I recall working with Mr William Walter Frederick Southwood, who is a beautiful surgeon. But when it came to closing wounds, he closed the skin with interrupted black silk sutures. I invited him at this stage to actually have a cup of coffee and I closed the wound with a more modern suture. But silk is still very good. It is easy to use. It is soft and it could be used on the palm of the hand, the sole of the foot and into triangle areas where there's a rubbing and is also used in dental surgery in the mouth. So the days of silk and black silk have not gone but reserved for those purposes. I'm gonna bring you over two. I model him and I've actually made a very large incision right down to the bone in this bit of pork belly. And I like the fact that it got a tat on the top because we can talk about tattoos. And I have a lovely collection of tattoos myself, not on me but of patients who have had sternotomies and I brought the words together and manage the tattoo. So your placement of the needle muscle cause you at death is just halfway long. Remember no space between the tip and the shaft and angled out because you're working at depth because the monofilament and there's a P DS, which is a poly. This is very good for deep tissues and fascia and has maintained its tensile strength which loses at about 50% at four weeks. It is totally gone in 100. And the problem is with these without glides to the tissues, easily, too easy because it can tear out. So what I'm going to do here is come further down and we're going to look at this at the very bottom of this wound. I have bone and I'll just, and it was shattered in there. I, the very bottom of this wound, I've got one and I want to do bring the bone to reinforce that the non-absorbable wires and eth eon are used at deep levels. But as you can see each of these muscles has a fascial layer and it's important when closing to bring me together. Mindful of the fact that if you're too close to the edge of a fascial layer, you into the lag zone and the lag zone is the area of maximum inflammation and if there's in, it is likely to cut out. So we're gonna start off by putting our first layer in deep. But I'm gonna come from inside out and outside in to actually make sure I bury the knots. I'm coming inside out and to outside in. And that way, that huge knot that I showed you is going to be deep in a way from more issues. Now, whether you use a Monona like P DS or use vial in the moment is really a surgeon's choice and there's no difference between the two in wounds in particular from the evidence. So remember with a continuous suture, each stitch it is placed. Oh, I've got, I've got a lot of shadowing here. Yeah. Hold this up. You hold that up. We're just going to try and improve the light. Ok? Yeah, I'm just trying to improve the light for you. I sit there. Hold this, please. Yeah, if you hold that up, I hold that up and just follow with the other hand. Yeah, that's fine. If you follow, hold the light with your left hand, follow with the right. Ok. Thank you and just come back it. So with each, each time place and I'm doing it in two, I'm doing it in two because I am not 90 degrees across both. And I'm picking up the fascia and not the muscle itself because otherwise I'll be strangulating the muscle, just got each and every stitch needs to be placed carefully, place, rotate back, point it into the tissues. And I'm going to do this in two. It's important that you respect the tissue and you don't pull it through hard because often I see people do number of rows, just hold it up for a second now and they go through, just don't let go for a moment. I'm gonna do it again and they think they're saving time by taking the suture in and out of the tissue and then pulling it through like that, if you do that, this bit is tight and that bit is loose. So please, each and every time you put a suture in consider each throw, each throw as an individual suture to be placed and positioned properly. And that the tension is taken up by the surgeon and held by the assistant approximating the tissues rather than strangulating them. So I'm not going through the muscle. I'm bringing the fascial layers together. Usually the spacing you should not be able to admit the tip of your finger. OK. So the tip of your finger should not go in between. In other words, it's about a centimeter apart and a centimeter deep there, s no compromise on the needle position just because you're doing a continuous suture. Because the same principles as we have demonstrated to date with a banana apply to all these tissues. So therefore, respecting the tissues at each and every step with proper rotation of the needle is of paramount importance. The other suture we can use in deep tissues is a viral suture. And there we go, that's a vil is a polycin. This is an absorbable suture and it behaves like cotton. It comes in two types. One is dyed and it dyed to help you see it in deep tissue and one is undyed. The thing is is that you get closer to the surface. The dye in this tissue suture can actually tattoo the skin. So if you're anywhere near the skin, I recommend that you'd use an undyed. The standard or coated vir has a tensile strength that reduces at three weeks and at 70 days is gone altogether. This is vir plus and it carries an antibacterial agent triclosan and it is now recommended by nice for closure of deep tissues because of that element. Vil does have a rapid which uh 50% tensile strength reduces at five days and is gone in 40 days altogether. The thing about this vir suture, it is actually easy to use. It has similar tensile and lasting properties as the P DS, but it is much easier to use because it's coated, it doesn't tear through the tissues. But as a matter of habit, I always bury the knots anyway underneath because of the potential of pushing through the wound and the skin same again. So some surgeons will always close P DS, some surgeons will close vir I don't think you can, somebody can correct me if I'm wrong. Anybody has come up with a evidence of one over the other. And again, I'm focusing on that fascial layer, maintaining the tension and maintaining the place point, rotate principle that I talked, been talking about for the past number of weeks, I'm just bringing the tissues together. So they sit together. I'm not pulling the suture tight and I'm not strangulating the tissue, But I'm focusing on the placement of the suture and focusing on the tissue itself. Ensuring that as I'm going through, I can feel the tissue and feel as though I'm going through a little bit of leather like material, which would be the fascia in bringing all these layers together separately. I am ensuring that the function of one muscle moving over the other is maintained and the potential to recover if there's a lot of debris or dirty tissue in the wound, a infection rather than a continuous suture, we would recommend interrupted sutures to allow the wound to drain out. The interrupted sutures are also useful in inflammatory tissue or in tissue where the blood supply is compromised because the continuous suture, by definition is strangulating or potentially strangulating the tissue. And one be mind mindful of the blood supply and the healing involved. Once we come to the more superficial layers, we need to actually think about moving to a undyed suture. And let me just, we need a bit more here for for closing, we need, I need to close this tissue a bit more actually, the monofilament. But the great suture vir it is possible to stitch this oh out of somebody following, but you need somebody to follow to maintain the ti tension of the tissues. Now, the skin doesn't come together by itself. Each and every layer needs to be anatomically aligned. And if that is done, the skin comes together automatically a skin, a poorly closed wound is not going to be brought together by any form of skin suture at all. So, attention to detail is vitally important. And one of the most difficult rooms that I came came across in doing my training is closure of the an open thoracotomy because you have numerous layers. And if you didn't align the tissue properly, one would end up with a dog ear at the back. And this is usually on a postural surface where people are sitting against the tissues and it'll cause discomfort. So I'm now using an undyed vir suture because I'm in the more superficial layers. It's not necessary that it's dyed because I'm superficial and I can see the suture correctly. Same applies each fas layer is same principle. Now again, I am not using my forceps to correct the angle of my needle. But as I'm going along in a continuous suture, I need to be mindful of the pickup and the rotation of the needle you can see there already before I even put the skin suture in because I've approximated the tissues correctly and accurately, the skin suture is going to be literally the cherry on the top. It's very satisfying. When you've got multiple layers to close to reach this stage and have the skin wound almost sitting together without any further sutures, it gives you a good indication that you brought the tissues together. Well, now, between the skin and this layer, one finds a lot of fat, but there is a fascial layer, scarpa's fascia between the deep fat and the superficial fat. But a continuous suture is not a good idea in fat because fat has a very poor blood supply and a continuous suture will very likely squeeze or the fat out and cause fat necrosis. So the best thing to do when it comes to a fat layer is move to a horizontal mattress suture cause the horizontal mattress suture is not it going to strangulate the tissues. And in the with the horizontal mattress suture, I'm going in and out the tissues forming. As you can see a ladder type of affect as I bring it together. And this is a very satisfactory way of bringing deeper tissue together, especially where you're worried about blood supply and fat itself. The 90 degrees, as I said, you is at a perfect angle and being able to come across 90 degrees each time means that the edges get pulled together properly like all continuous tissues. It needs to be brought together one stitch at a time. Please do not go three or four rows and then drag all the tissue together in one or mighty pool because that will definitely cause damage. So, having brought everything to together and that's interesting. I've now got my tattoo there. So what about the skin? Well, the skin interrupted sutures you can take out and simple interrupted sutures are very effective and very useful in inverting the skin edges and very useful if you expect there to be any leak or any infection because it is possible to take out one or two sutures and let it drain. The problem with the interrupted sutures is that the knots themselves are a bit spiky because even though it is a monofilament, it is breaking the skin in another place and therefore to contract down those and you cause action. So when interrupted sutures are in place, we would not recommend you getting them th soaking wet. In other words, wouldn't swim with them unless you had a waterproof dressing over the top until those sutures come out. Remember on ventral surfaces, healing is probably 2 to 3 days earlier than on dorsal surfaces where the skin is thicker and on the back. And I'd leave them in on the back for about 10 days and on a VL surface seven days and on the face, probably five days. But that was all dependent on the blood supply. So interrupted sutures, simple interrupted sutures are not strangulating the tissue. And I prefer to use a 50 yeah, suture. And in a tattoo situation, I'd bring the tattoo together and it's, I think I've actually go to shift there in the tissues. I've actually ended up with a shift in the tissue. So there you go. That is demonstrated to you, even though I thought I was keeping the legs together clean and going over horizontal. This you can see is a tectonic shift and that I would not be happy with at all in real life. And we probably, well, not, probably I would take it down and have another go. People with tattoos often presented with for cardiac surgery and they prided themselves on their tattoos and I took pride in trying to bring them together. No, that's not, that is quite frankly not good enough. So I'll take that out, but I'd have to do that all. Again. The simple thing about an interrupted suture though is to go across 90 degrees from one side to the other as we have done and demonstrated with the banana. Now, some people use tooth forceps, but the tooth forceps are not for grabbing the skin. I've got the ends slightly open and I'm folding it back like I'm using chopsticks. The plastic surgeons would use a skin hook to fold it back to lift it up. Rarely the forceps as previously demonstrated caused damage and therefore would not recommend squeezing the tissue. And again, looking at that, if I'm being honest with myself, that's not perfectly across and is not equidistant from the edge and I'd do it again. That's the thing about doing things live is making sure you get a perfect no, directly across instrument tying one hand in shorter, one in long two throws taken down flat, lock it across that side and alternate the flows and cut and that is just bringing the edges together cleanly to get even evasion. Some people would actually use a vertical mattress suture that's going deep on both sides, then coming back and on the edge. But like all mattress sutures, horizontal or vertical, this is in itself causes a degree of constriction and I would not advocate it on every single stitch and I might use it occasionally just to get that little bit of aversion. But what you've got between the two, there is a degree of strangulation of the tissue interrupted sutures cost money and time to take them out and are inconvenient for the patient. And therefore many people have you decided to go to a Monopril? I'm just looking for the monocle in front of me is a drug there is and the Monopril can either be on a straight needle or on a curve needle. And this clear monochrome I personally prefer to use a straight needle. No, what I've started doing is because the knot itself causes a small nida or biofilm for infection. I use the monocryl much like patients used the straight proline. I don't put a knot in it and the proline because you're taking it out, you put a be or a clip on the end and I do the same with my monochrome as I put a bead or clip on the end. And what you're wanting to do is literally in the subcuticular teacher is go across from side to side all the way down making that 90 degree ladder. Some people use a curve suit needle, but I've noticed that in doing so, they end up what I would call a crinkle cut. You reflect the tissues back come directly across and progress. And the convenience about the monocryl suture is it is absorbable. It uh uh uh poin, it's clear, it's undyed. It's antiseptic loses its tensile strength in by 50% in seven days and is completely gone. I 120 days. And this is a fabulous suture to use on the skin for all clean operations. Well, we are not expecting any infection and you do not need to re remove the suture. As I said, I changed my practice in cardiac surgery to putting a lier clip at the top rather than a knot because I did find that the top of the wound and the bottom of the wound had a little area of crusting because of the knot just underneath the skin. So it's a little trick for you is to put a little clip on and that can be top and tea or cut off by the patient with it. Scissors probably at three days with each and every time you handling skin. Do remember the banana I've shown you and the effect of grabbing the skin edges, I would not knot it there and there you go. It its together the wound very nicely and you do not need to do anything further. But what about the dressing? Well, a wound like this is waterproof within 48 hours. So you can get in the shower and get it wet. But if you've got interrupted sutures in, if you get it wet, do pat it dry because you've got potential holes in the entry and exit. So a waterproof dressing in those circumstances is important and addressing is also important. For another reason, the mildest form of pain is itching and if you don't have a dressing on, the patient will inadvertently and unconsciously scratch it. When I saw a patient who went home with a perfectly clean wound. And when I saw him clinic, he had a really nasty local infection. The bug that grew from that could only been found in potting tomatoes. And he was an avid gardener in C SI style. I scraped his fingernails and sent them off to microbiology for culture, but they didn't complete the story because they said it was a waste of time. It would have been lovely to have seen the bug under his fingernails being the same bug in the skin. I'm pretty sure that was the case. So somebody's asked, what about a high BMI? Sorry, I was just going to read the question, but you saw it. So that's what about people with a, a very big BMI? Well, if there's a lot of fat between the skin in the sternum I started doing because fat is avascular. And if I couldn't see the fascial layers between the superficial fat and the deep fat, I would put a drain in and I would put a ready vac drain in to close the space to hold the layers together. And I left the re back drain in for three days in my sternal wounds. And that together with all the other things I did, I reduced a, a 1600 operations. My median all wound problem was reduced to zero. It was reduced to zero. No wound healing does not happen on a wing and a prayer, it requires meticulous attention to detail, respect on the tissue all the way through. And as demonstrated here on this pig belly, I would have taken that down again and re sutured it to make sure that scar was perfectly aligned because I obviously caused a shift and that wouldn't have been good enough. I had a patient who had a picture of Jesus Christ on a cross on his chest with two angels either side and I put that together perfectly. And I use that in my talks to say that wound healing does not happen on a wing and a prayer. So I talked about putting a drain in to suck the air out of the space to bring the tissue together, to enable that to heal. And there's a, a lot of debate around drains. The drain is there particularly in thoracic surgery when you got air, but a drain would also be there if you have infection or pus or collection of fluid. The other reason for a drain and plastic surgeons often use it. If you have a myocutaneous flap brought into an area, any collection of fluid will mean that that flap is not gonna adhere to the deep tissues and could separate and cause a problem. What's interesting is that looking at the literature and the trends, the need for the drain seems to be disappearing and the drain is not an excuse for poor surgical technique. A randomized controlled study looked at ventral hernias and found that drains caused increased wod infection drains. War is used in thyroid surgery because of the risk of a hematoma and lang edema with that. But that is going out of fashion because people are being more meticulous with a hemostasis. We always used to use drains and bowel surgery. But for a primary anastomosis in a clean abdomen that is no longer necessary is often used after breast surgery, but that has gone as well. And there's an indication that the drain is a site for possible wound infection. In a regular arthroplasty or joint replacement drains do reduce the amount of swelling but perhaps increased possible infection. So, they're all going out of fashion. The only times drains are now used are in gastric esophageal surgery and pancreatic surgery. Because if any of those juices got to the spaces, it would cause a lot of inflammation. And we always used to use a rubber rubber drain in bile duct explorations because the rubber drain caused intense inflammatory reaction and created an artificial fistula. So if there's any distal obstruction, at least the bile would drain out through the drain until everything was settled. You then leave that in for a good 8 to 10 days. So you had a good granulated fistula and then remove it and all fissures will close provided there's no distal obstruction and that's our drains we used for exploration of the common bile duct. I don't think there's much place now for grains. Otherwise, certainly the corrugated bits of plastic that we put in dirty wounds and allowed free drainage onto the dressings was rather messy. Some people still use that and put a stoma bag over the top drains also are not only a site of infection bite cause for discomfort, certainly removing them causes discomfort as well. And depending on its position, there is discomfort, make sure when you tie the drain in. And this is probably where you're more likely to use silk than any other suture is you put the knot on the dependent side. So in other words, the drain is not hanging or the or suture. And there in, if you look at our not series, the importance of securing a drain and doing the proper knot now becomes important because if you lose the drain, in fact, things get worse than actually putting it in in the first place. So I hope you have a better idea about suturing and closing of layers. You can't hurry multiple layer closure in a short talk like this and talk at the same time and focus on the sutures. You'll get the slide. I you could make a good argument to having a closing team come in and close. People have actually asked, do you change your gloves to clothes? I think it's not a bad idea, particularly if you've been working in a viscous that's potentially dirty or there's a potential a hole in the glove. Having a brand new team come in to close, gives you a break in decision. And actually the people taking over could specialize in the clothing, something I've thought about for a while. And certainly what Diva Shay does in his cardiac clinic in India where he's produced reduced surgery to a production line by doing exactly that the point is even though you're tired at the end of a long operation, you need to pay attention to the closure and all elements and think about each ditch. If pick up, then place point and rotate. If you respect the tissues, the tissues will respect you and you'll have better function and form afterwards. Remember what I said? The scar is your indelible signature on that patient for life and they'll remember you and everything you said and did by looking at that scar, it's worthwhile, spending time doing it. Thank you very much for your attention. And I look forward to seeing you next week as we continue our basic skills and surgery. Are there any other questions from anybody, Gabriel? I believe you answered them all. There was uh like a comment about the back therapy but um it doesn't look like a question, a comment about what V AC vac therapy. Oh VAC therapy. Yes. Um VAC therapy is actually extremely useful in dirty wounds and uh it increases the granulation. I think if you've got a very dirty wound, leaving a wound for secondary healing or secondary closure or healing by secondary intention is appropriate healing by secondary intention, takes a long time. So if it is really dirty and we've seen some dirty sternotomy wounds, VAC therapy is extremely good. There is also evidence for negative pressure wound dressings and particularly in obese people. The results are very good. There is particularly useful in incisions in gynecology and some abdominal wound incisions as well. How it works is increasing the blood supply but also supporting the tissue. The other things you can use to close the skin are blues. But remember you got to have a dry surface to have a glue. And if you get your gown involved, your gown will give glued to the skin. Steri-strips are excellent, particularly in linear incisions and useful in Children. They can be useful to actually close small incisions as far as clips are concerned. I'm not a big fan. I think they have been used for speed and in emergency situations. And if the patient is extremely sick, but taking them out is problematic and putting them in causes a lot of skin damage as well. But there is a place for this perhaps trauma surgery when speed and patient's vitals are at risk. So I wouldn't uh use them otherwise respect the tissues with the needle. But also commend you to look up online, the different tissues, think about form, think about function and think about the tensile strength required to hold the tissues together to achieve those objectives. Thank you.