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OK. Um So the elbow, um so a little bit about the elbow um in terms of the elbow, because we're running short of time, I'll, I'll come back a bit later to the Delta Pectoral approach. Um elbow arthroplasty basically is another form of um prothesis. We used to replace the normal surface anatomy of the distal humerus and proximal ulna. Um T for a short or total elbow arthroplasty trauma is now also one of the fastest growing indications for it. Now, they have been doing prosthetic joint replacements with regards to um the Carra toe basic, going back to ni uh 950 BC. The earliest attempts at elbow arthroplasty were resection procedures which performed as early as 17 80. And the earliest documentation of a total endos prosthetic elbow replacement um was of an ivory device designed to treat elbow resection for sarcoma by Gluck in 18 91. Gluck is also quite famous because he did the first total knee replacement a a about a decade or so before that. So these sort of designs were successful in the short term but ultimately failed because of instability or loosening due to poor fixation and understanding of the joint forces and kinematics around any joint. Um It wasn't until the 19 seventies that we got more reliable joint replacements. However, there's still some functional restrictions. Although we consider the modern era of joint replacement to be done in the seventies, particularly with the introduction of poly for fixation, um we still are evolving and getting better with regards for indications for um uh joint replacement. So with rheumatoid arthritis is the most common one. Um with about 10 to 20% of patients with rheumatoid arthritis, developing end-stage arthritic changes in the elbow, which of joint destruction and not benefiting from just simple radial head excision or sect toy and they have functional loss. Um You can also get pain and instability. Um Primary osteo osteoarthritis is a very um is another cause is less of a cause to do indication to do it, but particularly in advance when people are getting problems. Um and any failed elbow replacements as well. We need to think about fracture again, is becoming a more common indication particularly in the hemiarthroplasty. So, with a distal humeral fracture, with what we call the classic bag of bones, which is unreconstructed, interarticular distal humerus. Um A missed elbow fracture, dislocation again, is another form leading to post-traumatic osteoarthritis, which can become advanced again and again, that can also lead to chronic instability. Um And the generally the best person for an elbow replacement. The one who's gonna be the biggest winner is a patient with severely painful disabling rheumatoid arthritis, which has got severe altered articular architecture. Now, there are some contraindications, so active or recent elbow sepsis, generally an absolute contraindication for an elbow replacement because they don't do very well poor soft tissue envelope because you're very heavily reliant on the tissue envelope for stability, a nonrestorable function of biceps or triceps. You need to fix something else like a fusion in that situation. Patients with poor pay with compliance, um or with activity or weight lifting restrictions. So the reality is the an elbow replacement is not a weight bearing joint. Um And, and so maximum you could say they could ever lift afterwards is probably five kg. Anyone with flaccid paralysis of the upper limb extremity. Again, they're gonna have issues of instability and generally younger patients who are quite vigorous with activities. Um who've got a tra traumatically destroyed elbow. They may have to wait or you have to think of something else slightly, um less obvious ones, but neuropathic elbow joint, it doesn't, they don't do very well. They get destruction and they have loss of bone and it falls apart. Ankylosis of an ipsilateral shoulder. When they have a stiff fused shoulder, they won't be able to, they won't have much function. And the key thing with an elbow replacement is to try and get restore function so they can get their hand to their mouth and pull their trousers up or pants up. Um Again, we said again, younger patients generally less than less than 65. However, that is evolving as we're getting better elbow replacements. Um Try and avoid ones with olecranon osteotomies. And if the joints painless, um you can make it painful if you do an elbow replacement and it goes wrong. So a goal of an elbow replacement is to try and restore the functional mechanics of the elbow, um, pain relief and restoration of mo of motion and give some stability. So there are some things we need to think about when we're selecting the implant, the state of the ligaments and ST structures around the elbow integrity of the muscles, the amount of bone remaining around the elbow joint, um and the more constrained the pros, the prosthetic design will be in those situations where the patients got injured ligaments or poor bone stock or poor capsule or weak muscles. So, in general, um elbow replacements can be classified into constrained, semi constrained or unconstrained. Sorry. Uh constraint can also be called fully constrained. So, constrained and semi constrained tend to be linked, unconstrained are unlinked. So fully constrained elbow replacement is a metal to metal hinge with poly great um cement fixation. And they have a very rigid hinge design. They're designed with about seven degrees of rotation and some and some side to side laxity theoretically, the most stable designs versus an unlinked one. However, because of their rigidity, they can have high loosening rates compared to semi constrained and unconstrained design because they have less give and the, the weakest point then becomes the junction between the, the bone and cement interface. Uh We rarely use them now as they became, they got to go very loose or break, not just themselves, but also break. The bone. Classic ones are the stand mall, the D or the mckee designs. Um So this is a fully constrained D elbow. This is just comparing it with a knee replacement foca strain, knee replacement, which is the wealthiest knee. And this is, this was the old Stanmore in, in um component which you can see had loosening which then caused perforation of the anterior humerus and again, losing again as well seen in the, in the ulnar as well. Now, semi constrained are more commonly used. Now, it tend to be a two or three part prosthesis and the metal to a high density polyethylene. The articulation usually connected with a locky pin or a snapping fit device. But you have a little bit of built in valgus and varus laxity from side to side to allow dissipation of the forces because with the, the problem with I say with the old hinge, you didn't have this dissipation, it would find it. And the weak struct, the weakest point was going to be the bone cement interface. Um They're sometimes known as a sloppy hinge because they allow for this varus valgus rotation laxity there tends to be ven reduced stress on the bone cement interface, which reduces the incidence of component loosening. This is sort of a classic design for a sloppy hinge. So you got the sten um and you have the polyethylene, this is a white bit here here. Um And you can probably see there's some holes there where you have a little screw which links them in and there's a little, the movement is between this bit here. So that allows a little bit of varus valgus movement. Uh This is the implant that we use at Stanmore, it's called the Discover. Well, the discovery elbow now made by Lima. So this is upside down, but that's the humeral side, the ulnar side and you can see the polyethylene and it sits quite nicely and allows a little bit of movement. Ok. Um And it so cement well cemented in and doesn't. And it's quite, it's a very effective implant and very popular. So generally 5 to 10 year survival grades have been reported as high as 95 3% and at five years and 81 at 10 years. Unfortunately, the vast majority of patients have got rheumatoid arthritis. So they will have some further bone erosions and destruction tend to be, have better results of all the free designs, complication of early humeral loosening with designs without an anterior phang is quite common. Unfortunately. So this little bit here where it sits on the front that acts again as a bit of a stabilizer stops movement of this bit and makes it a bit bit, gives it a bit more stability here. Just some more different designs. So this is um trying to remember which one not that is the latitude. Um You can see the big hum anterior flange and has a bushing. So the locking pin that goes between it and so again, you can see this little locking bit bit. So this is a schematic version of it, then you have the unconstrained sort of these like surface replacements. These are two part prostheses. Um metal to high density polyethylene articulation without any locking or pin or snap fit. The parts are on linked in attempt to create recreate anatomy and duplicate the anatomical surface of the elbow does require good normal intact ligaments, good anterior capsule and appropriate alignment and good muscles. So, but if you don't have those competent lateral ligaments and soft tissue envelope, it will fail. Um Outcomes, instability is the most common complication because unfortunately, you have to go in and damage those mu those tissues to get into the joint, elbow joint, you have to repair them properly. If you don't, it will fail. Precise component alignment is also required. If you don't, if you get slightly out, it will fail. Um it has no proven superiority between uh semi constrained or a linked. Um 90% of patients may achieve good results dependent on patient selection and surgical technique are right. Um The most common problem is aseptic loosening because as I say, if you don't have it, if you don't have that good stability, it will fail. It did have good survivorship at 96% at five years and 84% at 10 years. However, um it, it does rapidly tail off after then. So here's an example of a constraint of an unconstrained total elbow replacement. So this is the humeral component, this bit slots into the ulnar. It tended to be either all P polyethylene self component or polyethylene sort of cup with a metal stem. Very important in terms of either one of those, you have to get your patient selection right, very key in elbow replacement. So, rheumatoid arthritis generally the most common cause of the reason for patient to have an elbow replacement. Now, um again, acute unconstructive fracture, um bilateral elbow ankylosis, you can think of as, as a good reason, as long as their shoulders are fine bony or fir ankylosis of the elbow with poor functional position. So you can get a bit better extension and movement. So the key thing is you're trying to get a functional range of movement, you can never promise you'll get the elbow fully straight, you can maybe get them elbow a bit more bent. Um revision of of a failed elbow arthroplasty. And again, sadly, a very common reason, um loss of bone stock because of trauma or tumor, um, less of an issue, end-stage osteoarthritis, post trauma, traumatic osteoarthritis in older pa patients, nonunion of distal humerus is who have poor function and poor and high pain. And I could also, again, used to think about in hemophilic arthro arthropathy as they could get quite significant sort, osteophytes and problems around the elbow joint itself. Um, with any sort of operation, you need to get your pre op planning, right. So we usually have our routine A P and lateral radiographs to help us assess the humeral bow because it, because it is not straight, there is a little curve to it and the melly con size and lateral projection. Um We also need to look at the angulation of the ulnar and medullary canal. Um There's definitely you need to make sure you get your left and your right the right way around because there're otherwise you'll be perforating the uh the cortex of the ulna. There are templates and now CT scan are sort of programs available to help us get the sizes right and help us design appropriate designs in terms of patients with um significant bone loss. Very important. When you're doing your examination in in the clinic, you do an ulnar nerve examination and document if there's any degree of impairments noted. Occasionally, they will have some issues which may require at the time of the operation, an ulnar nerve decompression. In fact, I would say most surgeons who do lots of elbow replacements will do an el an ulnar nerve decompression. Um as a as a progress, progress qui when they're doing their approach, if you got any concern with regards to the infection, um you should consider doing a joint uh aspiration to rule out sepsis with regards to your technique. So you can either have the patient place supine or on their, on their side uh with a, a lateral side of support. Um You would, most surgeons now would go for a straight posture, medial incision with a little curve around the ulnar side, around the ulnar side. Um identify the ulnar nerve, gently mobilize, protect it um and do your decompression and once you're happy, keep it out and keep it out of the way with some newer loops, no tension on it. So, a very common mistake is to put a clip on those newer loops which then cause drags on the nerve causes problems later on. Um Now, there are two ways of going about it in terms of the multiple different ways to go about it. A lot of people will try and keep triceps intact or um because it's very hard to repair, it's very hard for it to repair at the end. Um There are some different methods, it's called Pooley method, but in this method, I'm describing, we will carefully elevate triceps off the elect Quon um and extend our incision going between. Um So, uh so, uh sorry, the la lateral, sorry, lateral, sorry, the medial and middle fibers of triceps to allow us to elevate it off the back so that we can expose the back of the joint. Ok? You can then release the collateral ligaments on each side of the elbow. Once you've got a good enough bowing around, so you can see we're flexed, we've got the elbow flexed much like we do with the knee and you've got it exposed over the top, ok. At this tide, you can rotate the arm laterally to escc the elbow and allow exposure to the distal humerus. Um That's elect an osteotomy. Fewer people are doing that now because it's quite hard to repair back at the end. Um You remove the mid portion of the troch there. So this bit here. Um And that gives you access to the electron on fossa. So I know it's, it's empty here, but actually, it's got a bit of bone there. But by the time you've got through it, you've cut it there. Uh Usually with a bur you make a little con entry point to the root on the roof of the electron on faucet to get the right part to get into the medullary canal. We try and preserve the medial, natural portions of the supracondylar columns. So that's what we're trying to do. These are our, that's our little chocolate cut. We get our little reamer in to get into a good position. The aim is to find the center of medulla canal for preparation of this humerus. Ok. Once we're happy, we've got a good position, we'll apply a special cutting box much like a knee replacement. Um appropriate making sure you get your right and left the right way round. Um Or else you get a very dodgy looking elbow and then use your o slating sword just to get your cuts a little bit smoother, uh which will fit hopefully the appropriate implant. Uh We then have our spec our specific rasps um which will move the bone carefully at the same time. Key thing is we may use your this bit to get rid of this cortex here. Um I tend we tend to use a bur just to make it as wide as possible to allow our co uh our implant to start in properly. And then when we're doing the r um on the component. So just the tip of the ee Quon, not this bit here, but a tip here which will show better on earth and using a high speed bur make an entry point and make it nice and smooth to get into the medulla of the ulna. And obviously, we do for any additional bone for placement of serial rema. OK. So as you can see, it's not this bit but this bit of the Leno we've removed. These are the specific rema to allow us to get the shape right. And we use a burr just to remove a bit more subchondral bone gently around the coronoid process to widen this bit up to allow the condyle. So the prosthesis to fit in properly. I've been off with, we've sort of fixed these, we put our trials in to make sure we're happy and we use now place cement restrictor generally in the humeral side, there are very few cement restrictions that will fit into the, that will fit into the ulnar side. Some people use a little nub in the bone. Um You can use a cement gun but sometimes you just need a little syringe full of cement because there's no s because the guns are no nozzles are too wide. Um We want to make sure that our component is sitting in the middle of the e uh of the eon fossa there. OK. Um And again, this is us doing the similar sort of thing with the humerus. Again, we'll get a cement restrictor here because we'll probably fact then get our cement in while cement is soft, we put our humoral component in and does this is not, it's advised but not necessarily a such for um for all these components, you can put a little wedge of bone between the flag just to give a bit more protection. Um If it's well fitted, you don't need to do that. And then really important, then before the cement is set, you get, you align both components up and you put your your fixation across to hold them in there. Because if you don't, you could cause some rotation later on. Um If they're slightly off malaligned. OK. Once we're happy, we get the arm to maximal extension. While cement is setting wound closure, tricep, suture back onto the bone if released. So you can do a little, little sort of an uh Antero sutures to help get it back into place. Um with anything, there's always complications. So, loosening is roughly around 17% on radio, on x-rays and clinically only about 6%. Um And the most common f as I said, most common mode of failure for fully constrained infection unfortunately is still quite high 8%. But that's generally due to people with rheumatoid arthritis, a bit of instability can be a problem as well, particularly if you're not happy if you haven't got your repair correct. Um Pushing wear, those little pollies can wear away, particularly if they've been in there for a while. Wound healing, any sort of wound over the elbow can be a struggle to heal properly, particularly with patients with rheumatoid arthritis. And on long term steroid use, ulnar neuropathy is a common, was a common, is a common issue. Um really important though to when you do your ulnar release, that you make sure that you test the nerve at the beginning and at the end to confirm that it's working fine, um If you do take triceps off and it doesn't heal properly, you end up with triceps, insufficiency and it's really important as well. You can always end up with too, taking out too much bone. Um, or if they got rheumatoid arthritis, they get further erosions. You can have further bone loss and obviously with any sort of joint replacement, you have to worry about persic fracture. Ok. Moving on. So MC Q si think we will have a stop there for any questions um be going on for quite a while. So I'm sure people are bored. Hi, David. Hi. Hi. Um Thank you very much. Uh First of all, this has been a very comprehensive, it's actually a reference lecture and, and I know you are very busy. So thank you very much for taking the time to prepare. It's, it's really um throughout the lecture, I've trying to make notes of what I can make a comment on, but I couldn't find anything to add. To be honest, you have taken us through um uh the principles of shoulder and elbow replacement very well. Um You went through uh the indications the different type of prosthesis uh with the shoulder and the elbow, uh the surgical techniques, um potential complications, um you know, outcomes and longevity. Um So it's wonderful. It's, it's quite comprehensive and thank you for the case studies as well that you shared uh with us David. So that's, that's fantastic. I think there was one question um from uh Doctor Abin um I'm not experience uh much with um, elbow replacement, but uh you think there is a design that's convertible between total elbow arthroplasty or like a total arthroplasty? Maybe that can be converted to, between semi constrained to constrained or is it such a like a maybe, um, I think, is he talking about the latitude? Not sure. Maybe so. I know there's a few elbow replacements on the market latitude is probably the more common is the more popular one, the moment writing to use it a lot. So it's um it's used quite heavily in trauma, um particularly for the hemi arthroplasty. Um It has a anatomical component as well to it. So you basically um you can also do a radial head replacement. Um And then it, it can be from, I can remember, I've not used it very much, but you can know it, it is, it can be, there's an unlinked version and a linked version um which I think you have, you can decide on the day. Um With those ones, you have one, you have to have the good experience with it. You have to make sure you're happy that you're repairing your collateral ligaments really well. And that you've got good musculature. And as I say, you've got to pick your patient, uh pick your patients, get your patient selection right. It's difficult because unfortunately, as I said, the vast majority of patients we have with r elbow replacements are rheumatoid arthritis and so inherently, they're gonna have poor muscles, poor ligaments because of the rheumatoid. Um Yes, it has got a use in trauma. But the issue, as I say with trauma is generally people come to you with a trauma problem. Um for elbow have had a mis dislocation or they've had significant bone loss from a multiple um so comminuted distal humerus fracture classically, you know, the bag of bones sort of elbow, which so, yeah. Yes. So I know the Americans like doing it in patients, younger patients. Um But then that's the other problem is the younger patients have higher demand than the older patients. So, um we're wary about it. Thank you. So, so like um especially in trauma and rheumatoid complicated cases, good to have a versatile system that with you um Good to have a plan, but also have a system that allow you to change your plan if you have to intraoperatively. So I think that's um that's what, where it comes from. Thank you very much. Uh We have a question from uh Mohammed Nail. He said about uh infection with C I, I'm not sure what C I uh because it's um PPP C, I'm struggling to see how C I can be accurate. But if you let us know Mohammad, I am struggling to understand what is C I that you meant in your question. Uh Yeah, he means contraindication. OK. Oh, contraindication. So, recent infection is a contraindication. I see. So, yes, contraindication to obviously joint replacement. But he's asking what about if the infection is old chronic 10 years ago? But what do you mean, Mohamed? Is that infection old but still present or old and cured or do you mean like it's old but maybe insidious? Um, we need to understand exactly the key. Well, I mean, um, working here at the RNH, we deal with a lot of patients with chronic infections. So the problem is with anyone with, with acute infection, it's going to fail, um invariably will fail, not, not today, not tomorrow, but it'll fail at some point. But we do have patients who have been referred to have had infections for many years. Um If you have a patient who has a chronic infection, um uh you still have to treat them as if they've got an infection. So um we'll mostly do it in the stage procedure. So you do samples to make sure that you cleared it. Um a multidisciplinary approach with regards to microbiologist and appropriate antibiotics. Uh You have to accept that people with rheumatoid arthritis, they're going to have a higher risk of infection because of their pure immune, poor immune system due to the treatment that we have for rheumatoid arthritis. Unfortunately. Um So it is key that you have that sort of uh that multidisciplinary approach where you start them on antibiotics, treat them and then put the antibiotics in, sorry, the, the prosthesis in and then make the patient aware that they might need longterm suppression antibiotics in order to reduce the risk of having significant flare up bone loss, revision surgery later on. So you, you can get away with it. But certainly in the acute setting, if there's any sign of infection that can do it, cause you're, you're, you're not, you're not doing your patient a favor, you're not doing yourself a favor. Um, unfortunately. yeah. Yeah, I think that's safe for any joint, isn't it? Really? Yeah, I think uh first principle is do no harm. Uh You might convert uh a serious infection to an acute infection. So you have to make sure uh and never attempt these operations on your own. You have to have a multidisciplinary team approach for these cases whenever an infection is there that don't touch the patient with that consultation with senior colleague as well as with microbiology. I mean, the policy here at Roh is Revision Elbows. It's a two consultant procedure for that reason just to make sure that you're protected as, as a surgeon. Um Don't even, yeah, just having that security as well when you're in that operation. If you get a bit of doubt it, infection two heads are better than one. Yeah, absolutely. You know, I do that as well when I do revisions and knee replacements, I, I always get a second opinion to have a look. At least with me if I, you know, because you, your brain shows you what you want, what wants to show you if you only see what you want to see, sometimes it's good to have that second opinion in these complex scenarios. Um Thank you very much. Thanks. That's excellent questions. Thank you guys. Uh So we'll move on now to the MC Qs. Uh David prepared three Mc Qs for us to um enhance our learning. So um go ahead there, David, thank you. So, right. So, apologies. I, I did have a bit in the lecture about the Delta Pectoral approach, but then I realized it was another 10 slide. But from what you can recall, uh the Delta Pectoral approach, the inter is plane is between which nerves. So you got a, the axillary and radial nerve B, the auxillary, medial and lateral pectoral nerves c the muscle cutaneous and then the medial and lateral pectoral nerves and d the medial uh and lateral pectoral nerves. So, if we think about the Delta Pectoral approach, does anyone want to answer this or? Ok, guys, you can tap your answers or we can uh speak up if you prefer that. Don't worry, there's no marks here. You all passed already. So I is saying option B very good. Um Did they are saying the same? Excellent. Yes, Dianne Dianne agrees with them as well. Great. So um here's a little diaphragmatic one. So this is a, the delta Pectoral approach a little bit further along this is the subscap, um subscap Aris tendon coming off, but this is the deltoid and the nerve supply for the deltoid is the auxillary nerve. And then you have the PC, the pectoral muscles coming in le uh uh pectoris mas and pectoris minimus and they come in and the nerves for those are the medial and lateral pectoral nerves. So yes. So that is those that, that is the inter plane of the Delta Pectoral approach, right? Um Question two. So, indications for elbow replacements, the following are all indications for total elbow replacements except so we got rheumatoid arthritis, advanced osteoarthritis, ipsilateral ankylo shoulder instability. So which ones are, which one isn't an indication? So we have a split opinion here between C and D majority saying C uh one person saying D or two saying D so it's quite split between C and D. So fair enough. Um But we instability particularly after trauma is a common cause for people coming to come forward to have elbow replacements. In that situation, you would look at doing a semi constrained elbow replacement, um an ipsilateral ankylo shoulder. So that's a shoulder that's fused is quite, is generally a an indication for not doing it because if you got your shoulder in a fused position, you won't be able to get your elbow to your mouth, whatever. So they tend to, we tend to avoid those in those patients. But yes, so I would say C in the majority of surgeons would say C is the be, is the, is the answer for that one? Ok. Lovely. Yes, it's a right. Yeah. Good to have some controversy. Mhm Le last, last question. So complications. So following are common complications of total shoulder a arthroplasty except so we got glenoid loosening, humeral stem, loosening, subscapularis rep repair failure or median nerve injury. Guys. Which one is not uh a common complication. Yeah. Not a common one and be care, you know, part of this is to uh teach you the technique of uh answering questions. Yeah. So read the question, it says common. So it could be one of these is a complication but it's not common. Mhm So we have actually quite split opinion here today for sorry for this one between B C and D. OK. So, um well, I'm glad you all recognize glenoid loosening as a common complication. Um Humeral stem loosening is also a common complication. C subscapular repair is a very common complication if not done properly. Um Now, if you're gonna a median nerve injury is extremely rare. Um the most common nerve injured in total shoulder arthroplasty is the axillary nerve. So because of the position of the, where the axillary nerve is, um it is theoretically possible to injure the median nerve, but you'd have to do something very special. Um because it, it usually is well protected the more like. So the nerves most likely to be injured in the shoulder arthroplasty are going to be auxillary then radial and then if you're really having a bad day, the mus cutaneous and I would definitely put the median nerve quite low down on that front. It is theoretically possible. But we said as, as for us said, common complications and uh accept. So it's really, so that's one of the reasons why have these questions, these those two last questions because it's about reading the questions because they're very, they like to throw curve balls particularly in the Fr CS. Excellent. Excellent. Thank you very much David. Bye. So um uh any further final comments? No, I think that's it for my. So I enjoyed this lecture very much. Uh Many thanks to Mr Hughes, um our orthopedic surgeon colleague from Royal National Orthopedic Hospital for this wonderful presentation for taking the time out of his very busy schedule. Um Enjoyed every moment of it. Um Thank you as well to everyone who attended uh today. Um I hope you all learned from it. And as I said in the discussion, we will try to put this video on the channel for all of you guys to view. Uh Please stay in touch with mi we are looking for someone to help us with the doing some summary notes of these lectures. So if anyone is interested, have some interest in education, creating educational materials, let us know just to create some summary notes of these lectures of these series. I will be, you know, very interested to hear from you guys just email us um, on the orthoped Academy uh website. And, um, and uh, I hope you all get your certificates uh through me, you can apply and just, you know, all free, you put your feedback and you get your certificate for your uh CBD profile. So, thank you very much, everyone. Thank you again, Mister Hughes. And uh you, I hope to see you again everyone in the next uh in the next lecture we're planning on, on Monday. Ok. Goodbye. Good night. Bye bye bye, doctor. Goodbye, everyone. Thank you very much, David. It's pleasure you need to go home now. He's still in the Yeah, still, still work. I hope it wasn't too long. It was, it was wonderful. I enjoyed it. It was one, you know, one of those relaxing ones. That's what I like about your presentations. I can relax. Ok, good. I'm glad, I'm glad I'm glad that yeah, so I can relax, uh, you know, just chill out and sit back and just to watch. It's wonderful. Wonderful David. Yeah, it's really good. It's really actually a reference LEC lecture. I think I'll, I'll enjoy it and I think it's really good. All right. Um I'll try, it's quite big. So II I may have to, if I send it in several parts and you might be able to get it. I could to email it to you. You want that. Yeah. Yeah. Please send it on whatsapp. Oh, yeah. What's up now? Take two gigabytes, does it? Oh, wow. B blame me. I didn't realize that. Oh, thank you for that. I'll remember that. Now. Um, I've had so many big files on my phone. I need to send to different people. No, it's brilliant. I'll get it sorted out and I will send it across to you. Yeah. Yeah. Thank you. Uh Yeah, with the the old one with the MC QA. Yeah, send it to me as soon as possible and hopefully someone will step in uh or send me, you know, someone to be interested to make the sum notes of these lectures would be good to distribute. Yeah. Well, all right. Well, have a good night. Thank you very much for inviting me. Alright. You guys. Bye bye.