If untreated, tethered spinal cord can lead to progressive sensory and motor problems, so early identification is essential. Pediatric neurosurgeon Peter P. Sun, MD, breaks down cutaneous and other signs to check for as part of an infant’s physical exam, with images to illustrate which dimples, lumps and other abnormalities call for further evaluation.
Hello everybody. Um This is Peter's son. I'm a pediatric neurosurgeon. Um I mainly practice in Oakland also at Mission Bay. I think one of the common things that's useful for everybody is to have a basic understanding of spinal dystrophy is um and in particular what to look for in the office, who needs to be referred, who needs um you know, work up what is a normal dimple. What is an abnormal dimple. So that's what I'm going to um trying to cover today. Yes. So um just as a quick m biological review, we all remember that um I don't get rid of um the formation of the um spinal column comes from neural cord um that um we have Henson's Note up here and it shrinks down into the primitive hit into the nodal cord. And then um the soul mites develop around here to form the surrounding structures. And of course with no relation, we have primary no relation where the note accord induces. Then you're elected um overlying this too Neural eight. And this would be considered primary neural ation which is responsible for The spinal column from c. one um to S. Two Below S. two. There is a separate process that creates the Conus and the bottom of the spinal cord and the phylum. And that's from secondary. In your relation whereby islands of cells down at the bottom of the note accord. Um or where primary relation ends and they coalesced together to form the Conus. So this has some implications in terms of our science and symptoms to look out for. And uh so we're mindful that primary in their relation Uh is up to us to secondary nation is to S. five. Which basically accounts for the creation of the Conus. All right so we're also mindful that the spinal cord forms uh ah down in the coddle region with a variety of other uh coddle um structures. So such that uh Tetris spinal correspondents traffic is um is associated with anal rectal complex um And genital urinary urinary abnormalities. Alright so one thing to note that is when we're born the Conus should end at Um the body of L. three. But it rapidly ascends by 1-2 months between L. One. And then too. So what we will consider this normal level of the spinal cord Is at the bottom of L. two. Okay so it can be up to here but the tip of the cone it should never below the bottom of L. Two. If it's below that. Then in association with a just so anomaly. Then we had the definition of a tethered spinal cord. So the tip of the bonuses at or below L. To suggest that the spinal cord is heather. And even if we don't see anything on the ultrasound we look very carefully with an M. R. I. So the um ah conceptualization of tennis spinal cord is that we have a defective dorsal midline formation. Um either from spina bifida Myelodysplasia spinal dystrophy is um it allows an elastic elements refused with the spinal cord at the bottom of the spinal cord and it tethers it as we grow vertically over time. Okay, so there's uh some of these malformation happened very early on for example the split cord malformation or dia Somalia is a split that happens during gas relation when the spinal cord uh or when the nodal court forms and goes down throughout the embryo. And this is a picture of it where the spinal cord is split in two. And then there's also um uh in biological uh associations if we have that retained central track the ventral tracks. And also sometimes have a neuron. No and there exists associated with it. But mostly I want to talk about um uh those are the the less common forms of spinal strategy is um of course one of the most common ones. And everybody knows is when we have um spina bifida, right? Spina bifida is an abnormal primary neural ation where we have failure of uh no relation. And we all know what that looks like. It looks like an open placko code. And we have spina bifida with its associated you know neurological um dysfunction with regards to the exposed plaque code uh with some degree of um you know um weakness distantly and batteries. And in terms of a tethered spinal cord, it's not an open defect. It's a close defect but it does lead to a stretch spinal cord, ultra blood flow when we grow vertically and progressive neurological deficits. If we don't catch it and diagnose it and fix it. So in terms of how we get a tender spinal cord we could get it from abnormal primary neural ation whereby although the spinal cord does close okay it's not an open defect. It does close. But it's this when it closes it doesn't close fast enough and there's abnormal disjunction between the ex adam and the note accord so that when the spinal cord is formed there are streaks of mesenchymal elements that can be attached to the spinal cord. And this represents the tether. And M. R. I would suggest that when we have a fatty lump on the back it's not just a fatty lump that this actually is infiltration of the mesen keen into the spinal column and we're attached to the bottom of the spinal cord. And then we have a very complex situation where we not only do we have to tether but we have the most bankable infiltrates that can displace normal sacred developments and Children with lipo moves like this do also have newborn or congenital neurological problems with regards particularly to sacred formation and they have our bladder difficulties. Much like the open defect patients do and inter operatively. This is what we would find in terms of trying to untether it. We have a big lie poma that's underneath the skin, it's attached to the dura. It's attached to the spinal cord it actually pulled the spinal cord so coldly that the end of the spinal cord is at the bottom of the sacrum and nerve roots actually go up. Whereas of course the normal anatomy would be like the spinal cord would be here and we will have normal nerve hoods go out this way and this situation is reversed. And if we and we carefully would separate this here so that this like coma does not cause stretch on the spinal cord here as we grow right vertically. So the other thing that can happen is that we don't necessarily need a dramatic lipo mahir. We can just have a subcutaneous track that goes through dorsal elements and be attached to the bottom of the spinal cord such that it pulls it to slightly beyond the normal level which is 543, right? Like we talked about and that's what this would look like intra operatively. This would be a dimple that goes through the dura. Be attached to the spinal cord. And this is the door open. And you can see this attachment goes introduce really into the bottom of the Conus. And if this is an open pit, it can serve as a track for infection as well as tumor order, moyad deposits and certainly as a tethering leisure. So we can also have terrace spinal cord from abnormal secondary in your relations we call secondary in your relations from S. Two to S. Five. In this situation we have what's called the fatty phylum or the terminal lymphoma. Whereas instead of a normal end of the Conus here we have a lip oma that is attached to the Conus that serves as the tittering leash. And this is what this looks like inter operatively with your open. This is the like poma. Uh These are the normal nerve roots and then we section this to prevent future neurological dysfunction from the gathering. Where is it being cut? And the separated or intended spinal. Okay. So certainly as we talked about a little bit earlier when we have coddled this genesis with abnormal neurological neural development within director or genital abnormalities. And these patients need A. M. R. I. To screen for um a terrace spinal cord. So in terms of diagnosis, what we see in the office 80-90% I would say 90% have to Tania's manifestations of Tetris spinal cords. Of course we don't screen all babies for tethered spinal cords. Um We screen for high risk patients with que titanius manifestations and those patients with the cardio abnormalities. So I'm gonna I think this is where I think it's very useful for everybody to have this framework of what to look on the back during our newborn examination two. Find out if there's any suggestion that this is a possibility. Okay so we're going to go over these things. Simple about decreased capillary or a hemangioma with this trophic skin. The lip oma that we showed hair tuft here, that you can almost braid actually as the rule. Asymmetrical crease in my appendages. Alright, so dimples that represented the spinal cords are from a thermal sinus tract that is above the inter gluteal cleft. Right? Remember that secondary interrelation starts at S. Two S. Two. Cutaneous lee is the top of the second from the top of the gluteal crease. So if we have a good little crease here, that ends here. This is the feet. This is the top. And if we have a dimple that's above decrease, this is abnormal, right? Even if you got an ultrasound on this and it's normal. It's not normal. Right? We have to get an M. R. I. On this patient with the um and then it just happens to have a humanity a moment. Of course it always it doesn't. This is another dimple. It's bizarre looking. You can know that just by looking at it. But the location also is above the crease, right, decrease. Is here anything above the crease in terms of the dimple is abnormal. It can be very benign looking such as tiny little dimple but if it's above decrease this is abnormal, it can be slightly off midline. This is actually a poor that goes to the bottom of the Conus. Like we saw on the internet pictures and represents that track. Okay. Whether the simple is shallow or deep essential component, its its relationship to the gluteal crease. If it's above the gluteal crease. Like this, this is abnormal. And it can be frequently associated with this trophic skin or hemangioma. All right. We saw this one that um previously that that dimple is not just a dimple, but it's associated with this track that goes inside the spinal which serves as a hedren lesion. It can become mass lesion in the source of infection. What people described is that there is sebaceous material that intimately pops through that pore, right? Because it's lying with epidermis. How about the temples that we see all the time Fake rock, oxygen dimples up to 2% of the population has them. These are dimples that's within decrease, right? So they're not above decrease. But if you spread the crease, it's right there. It can be shallow or deep. You put your finger there and you can fill the coxes. These are normal dimples. These do not need to be screened so they're in the crease. It's near the tip of the cottage that does not extend to the spine. 1 to 2% of of infants have this, I guess on rare occasions they can become infected and become a you know, another type of problem Later on. Double dimples can exist above decrease. This does not necessarily represent a tennis spinal cord. Like the, you know, like the single dimples here, but this also needs to be screened, right? Simple. Again above the crease. Um is spinal dystrophy is um until proven otherwise. This is a corollary just to remind everybody that just kind of midline malformation that creates a dimple does not only happen above the crease in the lumbar region. It can happen anywhere along the midline, predominantly at the nation. To and this is not a cute little dimple. Oh this is a demo sinus track that goes from the nose into an intracranial derm. Oy as you can see here. Okay. How about for capillary legion? So certainly babies and can have hemangioma that's very common. Wasn't here here? But the ones that are associated with her spinal cords usually have some component or do have some component of this trophic skin like this. Right? The skin is clearly not normal, right? This is again a dimple a um hemangioma associated with her spinal cords. The skin is well. First of all it's lumbar, it's somewhat close to midline and its associated with this trophic skin. And this is the M. R. I. For that patient which shows that that area of destro fixin and hemangioma is a tethering lesion. That letters to the spinal cord. How about faint commando almost like this you can occur here. It can occur here if the skin is not destro thick it's not associated with the spinal cord. Alright here's another dimple that uh is slightly hired. Uh But then we have this um human genome a with somewhat of a distraught, thick skin. So that's the Tetris spinal cord like here. This is a just a normal hemangioma that envelopes over time it happens to be in the lumbar region. This is not associated with spinal cords. This patient had an M. R. I. Because um it's got so so big it came close to the spinal canal. Of course. This is the lumbar lipo MMA. This is not something that we just want to shave off by the plastic or general surgeon. Same as here as a big lie poma. And these are the ones that have tendered us spinal cord component to it. Finally we have baby fine thank baby hair like this that is normal. But if we have patch of hair that's almost long enough to braid this is a cutaneous uh schema to for tethered spinal cord in particular is the split cord malformation whereby we have a piece of bone uh that we see earlier was from a defect and gas relation that resulted in um This piece of bone that anchors the two chord and tethers it right at the notch here. How to deviate increases. Certainly recognizes the big deviate increase. And this is spinal dystrophy is um as well until proven it about minor DVD creases. You know, there's a lot of patients with this. This is not 100%. You know like this is This is about 15%. So we see this. I would say we get an ultrasound and the ultrasound is normal. I think that that's the end of it. And then we have also midline appendages such as this. This is not of course just a midline of vintage. This is a tethered spinal cord and um needs an M. R. I. To assess the uh spinal components of this. Alright so Besides those cutaneous lesions we also recommend M. R. I. When patients have sacra genesis when they have in preferred anus up to 54% of these patients have a terrace spinal cord. And as well as these more bizarre and unusual you know um genital urinary abnormality. So what are the clinical features of these patients? Um They cause um the tethering causes um sensory assaults, motor dysfunction, bladder dysfunction. So when kids start to talk they would say you know they were not going to say I have procedures in my feet. So what I what we hear our rocks in my shoes, spiders on my feet Fizzing up like seven up in terms of lower extremity symptoms. And the bladder is one of the first um things that gets affected because the fine sacred nerves when they get stretched some of her first symptoms comes from the bladder where we get stressed or urgent continents get post void, dripping frequent U. T. I. S. Delay in toilet training. Um Constipation or multi factorial. So that's actually rare uh that it would cause just constipation. But then patients go on to have back pain. They can get new spasticity or weakness. They get ankle or foot deformities. And then they also can get rapid painful new onset left curve scoliosis. Okay so this is an example of a hammer toe which is something that we look for when there's nerve imbalance defeat Or one is bigger than the other. Um Or also in this we can see high arches developing and these are the um muscular skeletal manifestations of spinal cord tethering participation. See the colonists all the way down at S. One. So how do diagnosis should we start with an ultrasound? I think certainly when you see pimples that's above decrease you can big fatty lumps. The dystrophin hemangioma is that I mentioned. Those require an M. R. I. Okay you can start with an ultrasound but we know those are required memory because they are highly associated with spinal dystrophy. Is um and we can't count on a. M. R. I. Or ultrasound alone. And certainly for us for surgical planning, we need a memory. Um And then for those patients who we see a Conus below the L. two, we look carefully for lymphoma or fibers phylum that's greater than two. And when we diagnosed and status final court frequently we order your dynamics to make sure they don't have some sort of um sacred dysfunction. But we know that the big lymphomas are the ones that are most at risk for that. And the other ones such as the terminal lymphoma fatty phylum. They're not necessarily associated with abnormal bladder function because they did not displaced the normal development of the Conus. Such as a big like coma with. So we usually don't get the M. R. I. Read at birth. Um we wait until 3-4 months of age, better. Tolerating anesthesia. We can see better when we're bigger. and we generally do surgery. Not at 3-4 months of age. Because remember the neurological dysfunction comes from subsequent growth and stretch. But we usually like to do them before one year of age when they can start to be more mobile because sometimes because of the Deuteronomy and the suture line would like to keep them flat for a day or two or even longer the suture lines really tenuous. So it's nice to get it done before the toddler age when they can start wanting to get up right away. And again this is a picture of our like poma surgery. See this is quite it can be quite difficult in terms of separating the lymphoma from the spinal cord. Like this it's a big operation. Those are the patients again that we sent to spina bifida clinic as well because they have a high rate of um bladder function. They also have a high rate of re tethering. We follow these patients because even when we separate the suture line uh the raw surfaces spinal cord likes to read together so we follow them carefully. So again the spinal lymphomas. Um, we followed them for a long time. We consider them, choose spina bifida patients, mm hmm.
