I invite the next speaker, Dr. Hinojosa from Spain, talking about craniovertebral junction abnormalities and skeletal dysplasias in children. So, thanks for joining us. Okay. So, dear Chairman and colleagues, thank you very much. I want, first of all, to thank the AANS for this opportunity to share with you some concerns about the treatment of CBJ anomalies in skeletal dysplasias. We all know that bone dysplasias are rare disease. They are a wide group of different diseases that are a common cause of growth delayed, typically dwarfisms. There are a big number, more than 200 of them have been described so far. And we know there's no cure so far for them. So, the aim is the early diagnosis and the proper management of the associated complications. Most of them are related to genes anomalies for the coding of collagen proteins. And the most probably well-known are the collagen 2A1, which is the spondyloepiphyseal dysplasia, or probably the achondroplasia. As you know, there is FAGF3 anomalies. They are known from far away in the times. This is a statuette, which is at the Aztec Museum in the Ciudad de Mexico, that shows a nobleman, which is probably suffering from a spondyloepiphyseal dysplasia congenita. Classical classifications show a difference between hyperplasia and hypoplasia. But we've seen from the last talk from our colleague from Japan, how things are going towards the genetics and the molecular pathways. Because probably in the future, the treatment for these diseases will be in the knowledge of the genetics and the molecular threads. But for surgeons, the knowledge of which part of the skeletal is suffering will help to promote an algorithm for treatment. This is what we're going to try to show you. So some of them will affect the axial skeleton, like the spondyloepiphyseal dysplasia. Some of them, the epiphysis of the large bones, like the multiple epiphyseal dysplasias. And many of them will affect as much the axial skeleton, as much as the long bones. They can be, as you know, extremely severe. And it has to do with the different anatomical characteristics in the occipital cervical union in children. There is a big spasticity in the ligamentum. There is a big volume, as compared to very low weight body disproportion. And sometimes there are horizontal or vertical facets in the CO, C1, C2 junction, as we'll see in a while. So this is a fulcrum between the head and the neck that will go a place to different anomalies. Dysplasias will give rise to bone deformities, to hyperlaxity, and abnormal bone deposition and resorption, which will have to do a lot with bone healing after fusion. So in the end, we will have instability, deformity, and compression. And sometimes we'll have a pure compression, as you can see here. Sometimes you have pure instability, as you can see here. But very often you have a mixture of everything that you have to take care of and treat. Typically, this is metaphyseal dysplasia, which is showing pure compression, as you can see here. Or in achondroplasia, very typical in deformity magnum, as you can see here. But also in Stickler syndrome, like in this case. Sometimes we'll have deformity. This is a very rare disease called diastrophic dysplasia, which is evolutive. We'll see this case in a while. But you can have also pure instability, as in this case, with a fulcrum very clearly distorted and needing fusion in the C1, C0, C2. As I said before, the mixture of compression, stability, and deformity is going to be the rule in most of these cases. You can see here this vascular impression with compression, deformity, but also instability that we have to take care of. Clinical symptoms very clearly have to do with the compression of the neural structures, but also with vascular symptoms, as the vascular vertebral artery may be compressed or distorted during the movements. And very typically, they have a trigger trauma as the initiation of all these symptoms. And very clearly, something that you have to expect these kids to go for. They are usually progressive. This is a case of Stickler syndrome at birth, one year, year and a half, two years. And when it comes to our consultations, at three and a half years with this severe deformity, as you can see here in the upper cervical region. So the question is at what time you will have to take care of them. And this is the final outcome. Not very beautiful picture, but very clearly restored stability and the compressed myelopathy. So I want to go with you through our principles of treatment. The three questions are, is there a compression? And is it anterior or is it posterior? Is it a reducible deformity? And in this case, what kind of reducibility we're going to achieve? And after reduction, is it stable or not? And if it is not, we have to go for a fusion. So the main objectives are to compress the first stage, neural structures, then try to restore as much as possible the anatomical landmarks, and then provide stability. Most of these cases in children will go through a posterior approach. Posterior fusion will be mostly indicated, but we'll see also some anterior approaches. And the approach for the compression will have to do with the place of compression. Is it posterior or anterior? And this is the algorithm of treatment that we use in our institution. We see cases in every of these threads of the algorithm. As a rule, they have been treated. There is instability and compression in the neurovascular structures. And things to bear in mind is, where is it compressed? Is it reducible, as we said? Which is the cost, because of some of these diseases will have to do with abnormal resorption or the position of bone. You have to take care when trying to conceive the healing of the bone. And also, very important, the anatomical landmarks. The anatomy will be different to these kids. This is quite old boy, but you see there is no posterior arch of the C1, and also no lateral masses for the C1. The sizes of the pedicles and of the laminar and of the lateral masses of structures are very difficult. The courses of the vertebral arch are often very different, as you can see here in this case. Look at the size of the pedicles, typical in these children. Very mild sclerotic, not wide at all. And the length for the screws, usually below 10 or 12 millimeters. Very often, we have to do asymmetrical constructs. We show you some cases and use as much hanks, as much as screws, to complete these fusions. The way the vertebral artery threads in these patients are also very, very abnormal. You have to bear this into account. Sometimes, the facets will be very horizontal. This will get placed to a very severe instability, as you can see in this case. But sometimes, also, you have a very vertical anatomy. And this is even worse because it's very unstable and it is very difficult to reduce to complete a nice anatomy. Or as you can see here, in this case, the lateral masses of C1 very often are absent. Not only because they are young children, but also because of the anatomical deformities typical in these cases. So, hypoplasia of C1 and C2 is very typical. So, even approaches for this standard Goldharms approach, we usually go below C1. In this case, sometimes you ought to go even through the lamina of C1. As you can see here, it's quite different anatomy in the approaches for these cases. When there is abnormality in the vertebral bodies, also have to bear this into mind because of the evolution and instability, and also because the fusion of the bone is not so good. It's a typical case of a spindolepathicial dysplasia. You can see this instability, this torsion of the C1, as you can see, with these very vertical facets between C1 and C2. Then you have to go most of the cases for very rare or asymmetrical constructs. We use, of course, the Goldharms with the Mager technique with the cross-right laminar technique to try to achieve restoration, as you can see here in this case. Also, another different case, you can see this is the odontoid, which is fused to the anterior rim of the front magnum. There is no anterior ring for C1, and again, you have to choose for different asymmetrical constructs. So, talking about age limits, is there an age limit for fusion of these children? We have achieved fusions in children until as young as three years. In literature, this is taken from Professor Goyle, also Professor Benzel, both of them have a huge experience in these cases. They have achieved fusions and instrumentations in children as young as three months. This is too much for us. I would be very, very scared to put these screws in a three-month-old boy. But this is done, and this is shown in literature by these giants. Well, the golden rule is to have several plans. You have a plan A in mind, but I'm not kidding, you have to have a plan B in mind and be extremely familiar even with a plan C and sometimes consider the possibility of a plan D. And this is a typical example. You can see here, this is this distortion of the anomaly between C0, C1, C2, this very severe compression. Typically, you will approach this case just with a C1, C2 fusion, and that would be more than enough. But you go into the surgery and you see there is no posterior ring, no posterior arch of C1, no lateral masses. So, we have to do a plan C, which was C0, C1, C2, and also C3 opening the posterior fossa and the foramen magnum rim and not attaching to C1, which of course we don't like that much. That's the only way to treat probably this case. No lateral masses, no posterior ring, and then decompress and stabilize. Fizz as much as necessary. These are evolving deformities, and there is resorption and absorption deformities in the bone, but as little as possible. This typical case, which was showing this ptosis, this is another stickler syndrome. You can see this very severe distortion of the anatomy between C0 and C1. This kid arrived into our institution in a tetraplegic state. Very soon after surgery, he was able to, to, to, to, to branch here. Sorry about the video. But you can see there, if you fix too much, he's going to be stiff. It's not very nice. So, again, another case similar. This neutral position. Extension is not reduced, so you have to decompress. The problem when you do too long, too long fixations is the outcome of these patients. And this is the very nice outcome after a very severe spondylopathy. But when he comes back three years later, look at this. He's done a lot of bone assumption over there, and everything's closed again. The bone is crossing over the threads, and there's a severe compression again, the posterior fossa. Of course, this is just decompressed with a bone drilling, and that's it. Cases for pure compression, they are easy to treat. Not always needed. This is a typical achondroplastic patient. Evolution is very nice by itself. Had not to be operated on. But as you know, most of the achondroplastic patients, they will have, this was Sandra, 18 months, achondroplastic girl, a very severe tetraparethesis with this myelopathy, pure decompression, always under intraoperative monitoring is nice to achieve a very nice result. Or in this another case, this also achondroplastic patients, very young. This is not an orthodontic treatment. This is just a pure compression case. She was operated on, and just a simple decompression did very, very well. Osteopetrosis, there are very rare cases. You can see here, this is a pure compression. This pure compression, this was four centimeters in length. This was given rise to a severe myelopathy with syringomyelia to the end of the spinal cord. A pure external decompression was sufficient to achieve a very nice result. So pure compression, very nice to treat. What if we have a reducible lesion, which can be immobilized? Is it stable? Well, this is the typical case for, for instance, osteogenesis imperfecta. This is an 11-year-old boy with a formatada of osteogenesis imperfecta, very mild. And this typical fracture, which will heal very nicely, only with a nano system. And this is after three months. We tend to keep these boys longer than the typical fracture with a patient without bone skeletal dysplasia. What is the case in stable after immobilization? Then you have to go for effusion. And this is the case, for instance. We tend to avoid wires. We always go for threads or clamps, like in the MAGR or the Goldharms techniques. Also the right, which is very nice, the translaminar crossing wires, crossing screws. It is very nice technique for stabilization with these patients. And this is the case for, for instance, spondylopeficial dysplasia with this osteotomy to them. Very nice result. Area downloads, again, it is reduced in extension, so reduced, and then fixation. And again, C1, C2, C0, very nice. Morpheus, morpheus have their own problems. It is a compression. It's also done to them with a panum. Then you have to decompress an extension. You can see here an extension. Everything opens, and it's nice. And then you just go for a fixation. And C0, C1, C2 system is enough to achieve, as you can see, a long-standing, very nice outcome. You have to take care of this in the future, this going for a kyphosis that we probably have to treat in the future. Or the last case for a multiple epiphyseal dysplasia, as you can see here, pure instability. Then we do a translaminar and clamps with C0, C1. It's enough to achieve a very nice result. Sometimes it's a mixture of instability and compression. This is a very nice case of an 11-year-old or 8-year-old with osteodentrodeum with a fracture in C2 and a severe instability. He came tetraplegic to our institution. This is the tip of the osteodentrodeum. This is the body of the C2. And the patient inflection is very compressed in extension. This is in the natural position. You can see here the compression. And in extension, it reduces very nicely. So this patient will go for an we tend to reduce these with wires, sometimes with Alice clamps, which is very helpful for these cases and a very nice outcome for this case. And finally, this is the end of the case. And finally, for the isolations, which are reducible and there's a compression, you have to take a look to the X-films and see it's a ventral compression, it's a dorsal, and then you will go to anterior approach. If it is instable, then you go to effusion. And if it's a dorsal compression, you go through the posterior approach. And this is a very, very rare diastrophic dysplasia. This is the evolution of the case after some years. And then we go for a hallow jacket restoration of the alignment of the anatomy. It's not so good, so we decide to do a posterior fusion first and then go to an anterior approach and decompress to achieve a decompression of the spinal cord. A very nice outcome. And this last case for the algorithm of treatment with everything is here. There is a vascular impression. There is instability. There is also a Chiari 1.5 problem in this case. She was tetraparietic spastic, very severe swelling problems. She had a nasal dysphonia and very ataxic. So in this case, there was no movement between deflection and extension, very mild movement. Some instability, but not that much. So we have to go for anterior approach. We do a trans-nasal odontoidectomy. And then in the same session, we put the patient downwards and we go for an occipital-cervical fusion with a suboccipital craniotomy amygdala resection. This is the amygdala of the cerebellum. This is the aspect. We have set C1, C2 screws in the lateral masses in the pedicles of the C2. And this is, look at the floor of the fourth ventricle. This is the foramen magnum. The floor of the fourth ventricle is coming up to C1, very low. And after fusion, this is the outcome of the Ger-PRE and postoperative after the endoscopic resection, the odontoide and restoration of the posterior anatomy. And this is the CT. And this is the long-term after three months of the postoperative period. So in conclusion, I like to remember that bone dysplasias are a big group, very different diseases, but they have very common pathophysiology. The CVGA anomalies are very common in these cases. And they can be very, very severe, as you can see. The fusion instrumentation are usually difficult in these children because of the incomplete or abnormal development of the anatomy of the bony structures that you have in these pathologies. But also because of the resorption and opposition of bone, which are very abnormal in these cases. And remember that the fusions in these children may limit normal growth. And you have to take into account the future of those patients not to provoke secondary deformities. This is the hospital I work in, Madrid. You are very welcome at any moment at Hospital Niño-Jesús. And I thank you very much for your attention. Thank you. That was quite the tour de force of abnormalities. We have time maybe for one question from the audience. I just had a quick question in that Morquio's case, once you stabilized it, did the PANUS actually go away? They do. They do. Yeah. What's the role of traction in these kids? Do you keep traction on for a few days? It didn't seem like you showed any of that. You mostly showed how you can reduce them or not. Yeah. How have you found traction helpful? Yeah, for stable patients, we do traction. But hallow vest is very, very uncomfortable for very young kids. We have troubles to find suitable hallow vests for these kids. Sometimes we have to ask them to Sweden. We bring them from Sweden for very young kids. They don't do okay. They don't like the hallow vest. And very often we have all these scarrings. Even we do very, very frequent screwing of the pins. So we tend not to rely too much on hallow vests unless you need a very long stability after the procedure. And as you say, before the operation, we keep them in bed with or sometimes sitting with a wheelchair and traction. But the problem with these kids is not only the instability of the ligaments, but as you know, also the anatomical distortion. So although you can get a nice reduction at the beginning, as soon as you leave the traction, they come back to very unstable. So yes, we do use them at times, but not so easy to achieve in them. I agree. Dr. Booth? Do you have time? Beautiful presentation, beautiful surgeries. You touched briefly on the connective tissue disorder Ehlers-Danlos. And in our country, there's an explosion of this diagnosis at the moment. Every mother whose child gets an MRI and has a little bit of cerebellar tonsillar ectopia thinks her child has Ehlers-Danlos. And of course, many neurosurgeons are performing occipital cervical fusions along with their Chiari decompressions nowadays. Could you comment on your experience with that? Yes. Thank you, Dr. Booth, for your question. I wouldn't say that in our country there's a big increase in the diagnosis, but there's more look on diagnosis for these kids. They tend to be misdiagnosed or underdiagnosed for many years. We tend to observe them for a long time. Unless there's a progressive deformity or, of course, a neural compression, we don't go too soon for fusion for these patients. So the genetic diagnosis is done. We follow them up in a multidisciplinary office with traumatology, neurology, geneticists, and neurosurgeons. And we just discuss them. And there is a progressive evolution of deformity, then we go for fusion. But also, I think that you are doing this question probably because of the risk of sudden death in these children after a minor trauma in the cervical region, which may happen. So if there is severe instability or deformity in the upper part of the cervical region, we go for fusion. If there is, of course, also dendritem, which sometimes is related also to the collagen disease skeletal dysplasias, we go for fusion as soon as possible. But if there is only an increase, for instance, let's say in the posterior distance of the C1, C2 laminar, which is sometimes what you see in the diagnosis x-rays, we tend to keep a close eye on these kids and not to fuse them too soon. I don't know if this answers to your question. Is it also your policy in your institution? Okay. Good. Thank you. Great. One last question. Hello. Great presentation. Gracias, Jesus. Can you comment on the role of a transcomulus group as an organization? Do you think this is more the point you'll use very much, or do you think it's maybe one of the options? So the question is just on the role of transcondylar screws. Yeah, that's a great question, Dr. La Fuente. Yes, we don't have any experience on condylar screwing. But I do agree that for some of these cases with very mild or small lateral masses for C1, they are the answer. We have not been able to go through these techniques so far. I have read several papers on anatomical studies for transcondylar screwing. But honestly, it's not that easy to achieve. They are very young children. Usually the occipital condyles below the age of three are completely flat. So as a theoretical approach, it is a great idea. But then in the clinical set, it's not that easy to achieve. I don't know if you have any experience in adults. You are a great spine surgeon. But in children, it's not that easy. We like to use it more often. Unfortunately, we don't have very little experience. But we found that they do, the only few cases we've done, they do have a huge grip. And they take the larger lever of the arm of having a plate on the skull, which also conditionates a lot the position of the final position of the head, which is a major problem for occipital cervical fusions in some patients. So I think in the adult, the condyle is well studied and the approach is well defined. And I think this will be the way forward. I was wondering in pediatric, maybe because they are smaller and they are, of course, the hypoglossal canal is one of the key issues there. You cannot hit it, obviously, because the solutions are very good. If the size on the shape on a pediatric patient would be a similar... I agree. I don't know any clinical paper on this talk. I only know about anatomical studies on cadaver. So I agree, it would be a great idea to take out those plates from these kids. I don't think it's that really achievable so far. Okay, I thank you. Okay, thanks so much. I think we have to move on. Thank you very much.

craniovertebral junction abnormalities

skeletal dysplasias

dwarfism

gene anomalies

treatment options

abnormal skeletal development