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I'm sure. So, uh c spine trauma, I'm gonna start with some basic uh anatomy biomechanics and we'll build up on that. Ok. So why do you need to uh know about c spine trauma? I know, I know most of you don't wanna do spines apart from the exam. I think a lot of you will end up working in units where you will be uh required to look after the cervical c spine trauma, at least uh to begin with. Definitely, uh if you're not working uh in the spinal unit, you will definitely be looking after all the back fractures. Uh If you look at the epidemiology, uh they are uh they call for a significant number of injuries especially within the spine. Uh And C two fractures are the commonest uh uh injuries that we see in the cervical spine. Uh The subaxial uh injuries, C six and C seven injuries are very frequent, uh especially in people who do a lot of cycling activities. Uh and the most of them can be associated with neurological uh I injuries and or neurological deficit. So, uh ii always feel that you need to, to understand any fracture you need to have a good knowledge of the surgical anatomy. Uh You need to know what are the differences in the anatomy and associated structures. You need to understand the functional anatomy of any part of your body, especially the musculoskeletal system, uh how they function. And that is extremely important and how you treat them and the mechanics of cervical spine. Uh The cervical spine is pretty unique in our uh within the spine and also in the uh in the skeleton. Uh and how do they move? What are the orientation of the facets? What do we call stability? And uh when do we call something is unstable? I think an understanding of all this is extremely important, not just for the exam but just uh otherwise as well. Uh evaluation of an injured cervical spine, of course, ST I could hear that he was talking a little bit about that and uh the man principles of management uh because as every other injury, you manage the patient and then you manage the injury, uh there are lots of specific injuries when we talk about survivor, that's fine. Uh You need to know a little bit about the cervical and the subaxial uh injuries uh because they are quite different. So, within the cervical spine, we classify the spine into a subaxial uh cervical uh spine which is uh uh from C three downwards up to C seven. And uh the anatomy is slightly different compared to the thoracic of the lumbar spine, literally get a little corer. Hello, someone talking in the back II think uh she had had his microphone on. OK. Uh So uh so you need to understand the, the, the anatomical differences within the cervical spine as we all know. Uh I hope you all know by now, especially if you are going to the exam, the vertebral body is are much smaller and uh more and they, they have a bifid spinal crosis. And uh we do have a foramen for the vertebral artery and uh anatomical uh landmark C seven vertebra has the long uh non bispinus sclerosis. And that's how you uh when you're drawing up your end landmark, that's how you identify the C seven vertebra. Uh So just further uh vertebral artery, uh some i it's interesting to know that so many person of the vertebral artery uh injuries are associated with spinal fractures. So, it's extremely rare to have a vertebral uh artery injury without an associated cervical spine fracture. Uh And uh uh it is not uncommon to see vertebral artery injuries in genic uh uh setup because uh in uh when we're doing our angio uh a CT of procedures or angios spine surgery, the risks are smaller when we do our a surgery. Uh But it's there. Uh But posterior surgery, there is a significant risk of uh an injury to the vertebral artery, uh the upper C the uh C zero C one and C two, I just have like uh has got slightly different anatomy. Uh and this is extremely important to understand and the way we manage uh upper cervical spine, injuries are very different to the subaxial spine. As we all know, see, one has got no body or spinal sclerosis and it has got two lateral masses and uh you will come across uh lateral mass fractures of the C one vertebra and it's called a shorter anterior arch and the longer posterior arch. And uh the C two, which is the strongest vertebra of all has called the dens, which uh uh defaults as the word uh as the body of C one vertebra. Uh This is something I'm sure probably has good, all will be extremely proficient in this uh when you're reading anatomy. And uh before you go to the exam, and you'll obviously forget about it after that. Uh the posterior cervical spine uh is extremely, uh there are a lot of important structures and you have uh superficial layer, intermediate layer and the deeper layers. Uh The thing about the posterior cervial spine is uh there are a lot of muscles which none of us memorize, but uh they're extremely vascular. There are lots of neuro uh neurovascular bundles and that's why we always try to stick to the midline gray that you can see on the picture on the left when we're doing our approaches, functional anatomy and biomechanics is extremely important when you're, when you're trying to understand the uh body part, uh joint or a fracture, you need to have a good understanding of the functional anatomy and the biomechanics. Uh So as with everything else, uh we categorize uh injuries to the cervical spine. Uh based on the mechanism of injury, it could be a compression type injury or a flexion extension type injury or a rotational type injury. And uh as I was main function, the cervical spine is divided into the upper cervical spine, which is the CNO, which is the UT, the C one and the C two and the lower cervical spine is the subaxial spine. And if you actually look at the anatomy and if you look at the skeleton, uh it's interesting because this is what defines how we move our neck. So the C one, the picture on the uh right top corner has got a concave, superior articular facet. So effectively, what happens is the OSI occipital condyle, which is nothing but a ball basically sits on it. And uh this articulation is what helps flexion and extension. And there are no disc material within this joint. And uh this effectively acts as a ball and socket joint. And if you want to nod your head, then you need to have ac one, ac zero C one that is functioning. And uh if you look at the anatomy of the C two vertebra, the uh the inferior uh facet of the C one is convex and uh the superior facet of the C two is convex. So effectively, it's two convex structures that are sitting on each other and uh hence, you can do your uh rotational movement and I call it the great Indian headshake. Uh So the C zero C one and the C one C two is what predominantly contributes to your flexion extension and rotation movements. And uh C three to C seven has got very typical uh morphology. Uh It's not just the bones that gives you the stability, it's the other structures, the intimate processes, the orientation of the facets and also the ligamentous butros, you have the anterior longitudinal ligament in the front and posterior longitudinal ligament in the back. So the functional stability, what do you mean by stability? So basically the the normal C spine should be able to withstand load. Of course, uh it should help you maintain a posture. And the most important uh functional element of the of the spine is to protect the neural element. And there are a lot of forces that goes through the spine and within the cervical spine, any compressive forces goes through the vertebral column in the disc. And if there is a failure due to excessive compressive force, it's endplates that fail first before the discs. So you can have a fracture through the body and the endplate before the disc is actually uh disrupted. And if you think about the flexion extension mechanism. Uh There are a lot of things that neutralize them, the paraspinal muscle, the intraspinal ligaments facets a PLL. So these are all the structures that are called giving you stability. So, uh I think it, you you probably will be resonating a lot with your knee anatomy, with your uh ankle anatomy where there are lots of uh mo movements that happen. But equally, there are uh neutralizing ligaments and muscles uh and rotation, uh rotational uh instability in the cervical spine is usually uh quite uh bad. And uh it is the restraint for rotational stability is the is the ligaments predominantly. So you need to have an understanding of what is functional spinal unit is when we talk about the functional spinal unit, it comprises the adjacent vertebra, the facet joints and the discs with the ligaments. So this is the the functional unit uh and this is responsible for the movement of the joint. It's not just the facet joints that moves or the disc that moves that everything uh is a functional unit. And uh this is a very popular uh uh slide, I'm sure you have all have all revised this because this is one thing that keeps getting, uh it keeps coming up in your exams, the orientation of the uh facet joints within the cervical, uh the thoracic and the lumbar spine. And this determines the commotion that we have within these particular areas. So when, when we talk about instability. There are only reasons why we treat anybody in your spines. And if you, that these two words, uh if you're really stuck with, just say instability and neurological deficit for anything and you'll be, you'll be right. But uh what do you mean by instability? Especially when you're talking about the upper cervical spine or, or for example, in this case, o cervical junction, uh there are lots of lots and lots of parameters, uh lots of classification systems uh within the possible cervical junction. When there is a rotation, axial rotation of more than eight degrees, we call it unstable and then there's a translation of the basion and or uh then of more than one millimeter, we call it unstable. And as I said, there are lots of classification systems which you do not really have to know. But the, the trellis classification for Atlanta hospital dislocation is quite popular where the ba can be either anterior posterior or there could be a longitudinal translation. Uh This is also uh quite frequently asked in your exams uh especially in your MCQ S the powers ratio for Atlanta Association. So you guys may have to memorize this. So uh by in, by definition, uh if there is more than seven millimeters overhang of the C one on the C two or if it's a combined overhang, then we say it's unstable, there's more than 45 degrees of axial rotation of C one and C 2 to 1 side, then we deem it as unstable. If there's more than four millimeters of translation of C one and C two, then we, we say this is unstable, the less than 30 millimeters between the posterior body of C two and the posterior ring of C one. This is popularly regarded as the space available for the cord. And this is again a very popular M CQ question and it's regarded as unsta being unstable and adult transverse ligaments. That's the only the ligament structures within the upper cervical spine are, are the primary stabilizers for your rotational movement. And if there are averse ligaments uh transverse ligament and it is unstable. Of course, if there's any sig significant ligament as de disruption in the MRI scan, you treat it as unstable, there are lots of classifications a lot more than what I've just mentioned, but none of them have been validated and there's no one way of trying to say this is right or wrong. So again, coming back to understanding cervical injuries, just make sure that you understand your surgical anatomy and the differences in the anatomy, the associated structures that could be injured within the cervical spine. You need to know about your functional anatomy and the biomechanics, what is normal and what is abnormal. Uh This is the meaty bit. We uh we all grew up uh with uh uh three column uh principles uh anterior middle and posterior column. Uh We in the spine will have moved away from that. And we have an A classification and uh it is extremely simple. You might look at it and think, oh, what is this? But I always draw pad to your guest Anderson classification. You have an A B and AC injury. So, and it's based on mechanism of injury and understanding this is quite simple. So if you look at the a type injuries, uh a type injuries are compression injuries. So if there is a compression mechanism, then you can have a minor avulsion, a wedge compression or a split coronal splitt or what we call the pincer type injuries, which is a two, it may be an incomplete burst or a complete burst. So the eight type injuries are all compression injuries and uh the B type uh I was telling you about the stabilizers for flexion extension. These are flexion extension type injuries. So that means you have stabilizers, which is the tension band in the front, you have the anterior longitudinal ligament in the back, you have the posterior longitudinal ligament. And if the uh the energy dissipates even further back, then you have the interspinous ligaments. So depending on whether there's an anti tension band injury or a poster tension band injury, then you call it A B type fracture. And obviously there are B1 B2 B3. Uh if like your Anderson classification, if there's any vascular injury, we call it type C. And similarly, in the AO uh spine classification. If there's any translation, then we automatically call them type C injuries. There are some subclassification for the facet types uh which if you guys are very keen you can look into. But fundamentally, there are A B and C compression is A. If, if you, if there's disruption of the tension band, anterior or posterior, then it, it's a flexion extension type injury. A type B, if there's a translational element uh or, or translational injury, then it is a type C injury. So just a few examples, uh a uh A zero, there is no bone injury or a very minor uh fracture or a spinal sclerosis fracture which is uh deemed uh fairly stable. A one is a tiny avulsion injury or a small endplate injury. And these are again, quite stable injuries. And this is again a compression mechanism. A two is a pin type injury where you have a vertical shear and because the anterior longitudinal ligament and the posterior longitudinal ligament are also uh intact. Uh This is a very stable type injury and we just treat it conservatively. Uh it when you look at the x rays for these type, uh the cancer type injuries, it's quite scary but these are extremely stable. This is when we start to treat patients. Uh The A three and a four type A three is an incomplete burst. Uh and the A four type is a complete burst where there is disruption. Uh involves the posterior wall. And whenever there is disruption of the posterior wall behind the posterior wall of the vertebral body, you have your spinal uh cord and that's when we start getting worried. Ok. Uh Type B distraction type injuries, B1 is a posterior tension band injury. Uh and this is uh uh classical of your uh it's a bony injury. This, so this is the classical bony chance uh injuries that you have all studied about. And the B2 type is a ligamentous uh uh poster tension by injury. And again, this is uh equivalent to your uh uh ligamentous uh chance. And we all know that uh a bony chance heals better than uh ligamentous injuries. And ligamentous injuries are quite unstable and the A B3 injuries uh this is very commonly seen. Uh this results in the disruption of the anterior tension band. And most commonly, we we see this uh associated with the facet uh fracture dislocation and they usually anterior tension band disruption. So it's ex e effectively, it's the mechanism of injury primarily is extension where you have extended the uh neck and uh the, the first uh break within the tension band is anterior and type C injuries. Uh These are very nasty injuries, uh translational injuries that usually associated with the spinal cord, uh uh contusion or even spinal cord uh laceration or uh we have seen a few transected spinal cords as a result of this. These are high velocity injuries. Uh They uh don't do, they don't do well. Uh facet injuries. Uh Again, the, the, the classification is quite simple. Uh they can be non displaced, uh they could be uh displaced with the floating lateral masses or they could uh also be unilateral or bilateral. So, I mean, you uh are describing a fracture of any cervical or thoracal lumbar. Uh In fact, if you start talking, using the ao uh classification, you will uh in the exam, you, you, you will actually look very smart and just look for the clues. If there is a compression type injury, then say it's an A a type injury, flexion extension and to your post tension band, it's a B type injury and translation of any form is ac type injury. They and stable again, understanding cervical spine injuries, just revise on your cervical spine anatomy. Understand the the the bone knee uh differences, the ligaments that are involved uh and uh mechanisms that can be wrong. You need to understand the principles of management which uh has been dealt with. I heard a few little things I know about your specific fractures. A few examples. Uh Just to fill the time. Uh This is uh patient, 59 year old fell down a full flight of stairs, uh had neck pain, both hands were tingling. How do you proceed? You get a CT scan that caused trauma, ct uh and you can clearly see that there is purging of the facets and it is predominantly an anterior tension and injury and the forces have gone through the disc to the posts as well. And you, you, we always get an MRI scan and many people ask why an MRI scan and this is for two reasons. One, if you have a patient who has got who's neurologically intact and you go and take the patient and uh do your uh fixation and the patient wakes up with the neurological deficit, then uh it's a bad place to be in. Uh And that's the reason why you want to know whether there's any associated cord injuries even though or edema, even though there is any neurology, they don't have any early neurological deficit. The second reason why we get an MRI scan for in all patients is you want to know what the disc is doing is if there's a big whooping disc sitting in the uh canal, then you know that you need to go fishing. Uh And that also sometimes defines whether you have, you wanna go anterior or posterior. And it also defines whether you can just get away with that with just stabilization or you may have to take out big chunks of bone and do a corpectomy instead of just the anterior discectomy and stabilization. Uh This particular patient, we went from the front, it was a single level bike fal dis fracture dislocation. Uh We took the discard and we put in a cage and stabilized it. Uh Another example, this is, in fact, Mister St's patient, a 23 year old female patient, gymnast, she was a trapeze artist and she was uh performing in a circus in Great Yarmouth and she fell directly onto her neck and uh uh you get an X ray as the MRI scan and the MRI scan is very clear. This is a significant uh type C injury because there is rotational instability and translation. Uh The patient had significant cord injury and uh needed stabilization, but I don't think the patient. So how do we assess these uh injuries of? You have an understanding of the Asia chart? Just be able to uh talk through the Asia chart if you're provided one in the exam. Uh and you need to have an understanding of all your uh myotomes and uh uh dermatomes. Uh definitely sometimes the, the simplest things are the ones that examine us. Pick on you the most uh most uh asked question during when I was doing the exam was what is the lax do? And many people failed that. So just I don't ignore the very basic things, just be very clear on these things. OK. At a little bit of complete spinal cord injury and incomplete spinal cord injury. When do you call it complete? When do you call it an incomplete uh you call it a complete injury when there's no preservation of motor or sensory function below the level of injury, a sensory should be within three levels of the uh lesion. And when there is absence of sacral preservation after 48 hours, then it's a complete injury. Priapism is not uncommon in nails. And uh uh generally, if you, if a patient presents to you with a complete spinal cord injury, especially within the thoracic uh spine, mid thoracic area, the recovery is extremely poor, incomplete when there is uh any motor sacral preservation, then we define it as an incomplete spinal cord injury. And if there is sacral, uh if there is sparing, if there is sacral preservation, then uh uh we call it an incomplete injury. Uh and some of the signs of fascicle sparing. Uh If there is uh Alex Longus, uh flexor Longus is working or if the perianal sensation uh returns or if the anal tone sphincter tone, especially the resting tone is normal, then uh we regard this as uh sacral sparing. Uh So these are defined as in spinal cord. So some uh timelines just for your uh exams, if you're going along, if you really have this kind of a session and uh the spinal cord injury, and if you want to get into the sevens and eights and you're really doing well with your session, you need to understand some of the timelines and the impact of the timelines that you have in treating these uh injuries. And generally, uh if the primary, uh we do recommend uh uh primary decompression in, in uh some of these models. But uh uh most of the time, if there is, if there's a complete cord injury, then uh the there is a debate whether you want, you want to go ahead and fix things straight away. Sometimes we do differ for the cord to settle down, uh back fractures and hangman's fractures. I I'll go through that. I know you had quite a lot of fractures. Uh MS ST spoke to you guys about quite a lot of fractures. So I think in summary, the, the key thing is uh know your anatomy, you should be able to understand the differences within the anatomy of the cervical spine. Uh What, what is an upper cervical spine? What is the subaxial spine? Uh Where does the vertebral artery come into? What are the associated structures that could be injured? You have your uh esophagus, the trachea, you have your car uh sheath uh and you have a significant number of muscles and neurovascular structures posteriorly, you need to have an understanding of uh what is the functional anatomy. Why? What is the orientation of the facets? Uh the upper cervical spine is predominantly what makes you move uh especially your flexion extension and your uh rotation, the subaxial spine uh from C three to C seven usually contributes only to uh about 5 to 6 degrees of motion at within each segment. And that's why uh when we do our fusions, we, the patients do not lose a lot of motion. Uh You definitely need to have an understanding of uh what, what is stable and what is unstable within the upper cervical spine. Uh know a few of these ratios, uh power ratio and a few classifications. And they do frequently ask about these in uh the M CQ S and occasionally the Viber less frequently in the Viber uh exams. Uh and you should uh know your uh uh mechanism of injury that defines a new classification system. Type A is compression type, uh A zero A one, a two are simple injuries. Eight and A four are uh incomplete or complete burst when they become unstable. B flexion extension type. The, the it tension band is the structure of the, all the poster tension band and the type C is a translational injury and uh they're extremely unstable just like you guys. This and ABC. Any questions at all, quite exhausting. Three hours of cle spine.