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SI Digital, Innovations and Learning, in association with the UCLA Department of Neurosurgery, Lindy Leow, its chairwoman, and its faculty are pleased to bring to you the UCLA Department of
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Neurosurgery 101 lecture series on neurosurgery and clinical and basic neuroscience This series of lectures are provided free to bring the advances in clinical and basic neuroscience to physicians and
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patients everywhere. One out of every five people in the world suffer from a neurologically related disease.
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This lecture in discussion is in the area of spine and spinal cord diseases
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Its topic is tethered cord syndrome,
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and as the speaker will say, it probably is more properly caused, called the tight phylum syndrome or the core traction syndrome.
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The speaker is Ulrich Badsorf, professor of spinal neurosurgery in the department of neurosurgery at the David Kefen School of Medicine at the UCLA Medical Center. Good morning everybody. Sorry
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about the confusion about time and thank you for the opportunity to share some thoughts about adult Tivid Court syndrome.
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Anthony Wong spoke about the pediatric variety some time ago. And just for the record, the nomenclature Tivid Court was introduced by a very well-known pediatric neurosurgeon, Harold Hoffman at the
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hospital for six children in Toronto. almost 50 years ago. And as you'll see, it's descriptive in that sense, but probably we could do a little bit better with some alternative
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nomenclature. And I'm going to make some introductory comments, long ones, a little bit repetitious, and then share with you our experience here at UCLA with 30 patients that Dr. Holly, Dr. Liu,
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and I have had over the years. So just by the way of record the terminology of tethered cord, the cord can be tethered anywhere along its course.
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We're going to be speaking about tethering in the
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Lumba region, but actually - We've seen tethering of the cord from inflammation, infection, subarachnoid hemorrhage, which can scar anywhere along. I've had one
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patient many, many years ago who had a tethered cord from a shunt of searing scavity. And this can be problematic.
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So just by way of review the anatomy, I don't have a point here, but the
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phylum and the external phylum is,
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of course, not the one that we address. We go intradurally, and it appears, as you'll see in a moment,
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that the dura
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coalesces at the very apex, lower apex, and then forms. what blends into the external phylum at that point. And there are nerve roots that
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are present all the way down to the tip of the comus.
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We can define tesicord as acquired from surgery, trauma, infection, and inflammation And the developmental ones that are mostly lumbar and occur in children and adults. And there are
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the surgeons experience those that are primary and have had no prior surgery. And they're defined as having a low comus position, as you'll see, but
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there's also in recent years the concept of an occult. tethered cord where the comus is in normal position and the phylum is still tight. We'll address that. And the treatment of that is somewhat
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controversial even this day and just as a matter of interest, the NIH is conducting a randomized trial right now or is going to launch it very soon to address the question whether occult tethered
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cord should be treated surgically or non-surgically. And then we all have seen a so-called secondary to the cord and adults, people who've had surgery in early childhood or infancy and then have
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later problems.
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The study by O'Connor is useful because it combines data from 730 patients. And as you can see,
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the average year of presentation is in. And mid-30s
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the concept of duration of symptoms prior to treatment is of interest because there are some people who would say anywhere from 3 to 5 years is the most that you can do before expecting permanent
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deficits in all regions. And the
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manifestations, external manifestations, you can see for yourself Many people have cutaneous or subcutaneous stigma deformities of the
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feet, scoliosis, and
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history of spina bifida. And just to illustrate these, I borrowed some illustrations from Neter,
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and this is just to illustrate the kind of foot deformity one can see.
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And the kind of dermal sinus one may see.
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Clinically, there are several different manifestations Weakness of low extremities with or without atrophy, pain, which can be low back in one or both legs. Problems with shrink to control both
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urinary and rectal, which can vary from urgency to incontinence, sensory symptoms. And as you can imagine, depending on the location of the conus, you may have spasticity
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And another paper. The presentation in
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this group,
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42 of patients had some kind of cutaneous or subcutaneous manifestations. School uses surprisingly is quite common and foot deformities
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Signs and symptoms, pain is a major mode of presentation and we've also seen motor deficits as you'll see sensory deficits and bladder dysfunction very often overlooked but sometimes
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let's say
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overreacted bowel dysfunction and only a few people have no problems
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the pain is rarely in a ridiculous distribution. It's often bilateral and interestingly, and obviously for reasons because the filum is tight, may be precipitated by forward bending or stretching.
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And it may also be in the perineal and anal region.
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Urologic manifestations are an important part of it. And the symptoms can vary from retention to incontinence, to frequency and frequent UTIs. And electrical testing, one can have both the trusae
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under or overactivity as well as shrink to dysfunction. And Dr. Nathan Sullivan in Oregon made this statement that there may be a subgroup of patients with voiding issues who have normal imaging but
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abnormal urodynamics and who can benefit
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And in those patients, he demonstrated
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histological abnormalities in the phylum.
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The phylum is composed of a pandemic connected tissue, peel surface and surface veins. And we've all seen the surface veins as a hallmark of
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the And this is from Dr. Sellers paper and in the upper row you see a histology of normal phylum and the lower one, you can see the increased collagen content and scarring of a tight
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And interestingly, there are different types of pathology. In fact, phylum terminology and adult is really, it's a mixed bag. And there's no one pathological entity. The most common
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pathology is some kind of fatty infiltration fatty tumor
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And this may be, in terms of some studies impaired secondary near relation tumors, again, like mom was a prominent scar adhesion from a piece of
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the rachnoditis collagen fibrosis
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is postulated and you'll see an example in a moment in patients with your standards, where it is thought that they repeat the over stretching of your brain. of the phylum in these hypermobile people
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generates some changes in the collagen of the phylum and makes it tight without necessary being low in position. And that's where this concept of occult phylum
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comes into consideration. Lymphosetic infiltration has been cited And then, of course, there's structural adhesions septae, which may be bonyseptae, duroseptae, and myelomeningosyos. And
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this is an example, again, the normal and what I was telling you about in Ehlers-Danlos syndrome where collagen changes have been noted. And Dr. Petra Klingi at Brown is a strong advocate Have fun
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Hey. on tethering people
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with illustrators in this situation.
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And this is just to illustrate that over the years,
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people have tested the strength of the file 'em and invariably come up with the conclusion that in adult to the cord, the file 'em is tight
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And I think from that point of view, thinking of it not as tethering, but rather as a tight file 'em helps me think of it in more physiological terms rather than purely anatomical terms.
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In Ocona study, as I mentioned before, some kind of fatty degeneration, or fatty tumors is very, very common And fibrous adhesions, split cord malformations are relatively uncommon, our
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experience, and some people have had a
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prior mile and meaning seal repair
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This also reflected
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in Beni Iskondar's study from 1988, again, like Puma, fatty phylum, very, very common as a part of the pathology
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So, the common denominator of all the pathological conditions is increased tension on the and nerve roots. And for that reason, as I say, it might be more appropriate to call it a tight file on
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syndrome
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because it reflects the pathology.
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Several comorbidities have been identified. We've talked about spinal disrafism and connective tissue disorders such as Ehlers-Danlos. There's some controversy about a comor did he with Chiari
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anomalies and I have to be candid. I think there was a group in Spain that recommended final section as an initial treatment for Chiari and they claimed great success but they had I think 20 patients
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in their report and Dr. Millratt said something like 14 of his patients had a
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of his. Chiari patients benefited because they had a tethered cord, but his criteria, as reflected in what he wrote, really used different
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criteria for identifying what a tethered cord is and that was based largely on clinical evidence rather than pathological evidence
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So the current thinking is that
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a tethered cord section, phylum section in Chiari patients is quote experimental.
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The function of the phylum to reduce traction on the conus and corticoyan herb roots with normal flexion and extension. And the dentates also play a role in this
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protection of the cord.
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And for that reason, repetitive stretching maneuvers often are the precipitating factors of clinical presentation, direct trauma growth. And then of the developmental comorbidities, we've all seen
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some patients who've had disc disease obesity because of the possibility that fat in the phylum or in the life hormone may increase with obesity plays a role in
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advising patients to lose weight or taking doing other maneuvers for weight reduction may play a significant role.
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Dr. Shoki Yamada, who was lived in Southern California, was at Loma Linda and was a, well, he was
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very interested in the court problems and made it a lifetime study and he did some experimental work in cats as well as in men and men and what basically he established is that there's a change in the
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oxidative metabolism of the chord and of the phylum when it's stretched and tight, which is relieved when the phylum is transected and the redox potential has returned to more normal after the
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chord has been untettered.
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This is what you use
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And this is just to show a couple of his signs. You see the return to more normal values. This was in man, this was also man.
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And the imaging findings are self-evident. The bonus is in most, but not all patients, minor bifida.
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You can see them for yourself.
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And this is just a few examples to illustrate the point. This is from Dr. Clay Counts, Atlas Dr. Clay Camp, by the way, some of you may remember him, he spent a year with us here at UCLA many
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years ago, and his practices in Germany So here you can see a thickened file on as indicated by the arrows.
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The fatty file on,
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particularly in this view, you can see the panel,
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and down in the actual image as well
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He's put a cord with a dural septum, and then he has one with a bony septum
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All examples of tethering and adults.
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terminal syrinks is also seen in some frequency
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So, there's controversy about the treatment,
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observation with repeated evaluation. As I said before, and you'll see in a moment, people, Arnold Manizis and others have said
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best results within three years or within five years of clinical diagnosis And certainly in very obese patients, it is worth a try
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to have the patient lose weight drastically to see whether that offers any improvement. But if you think about the physiology of the final mistite, you have to have substantial reduction in the
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amount of fat in the lipoma or in the coordination to
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affect an improvement
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So,
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as far as surgery is concerned,
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in adults, we can do laminectomy in the filing section or excision of the portion of the filing, subtraction osteotomy has been
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recommended for some patients who have had repeat tittering of the cord, and we will touch on that very briefly And of course, resection of the
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midline symptom is another way of treating these, which I didn't include in that list.
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And very important to do electrical monitoring, as we do here, too, on its patients you can see the changes
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Now,
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this is from the literature,
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relief of pain in approximately 80 neurological deficits improving about 60 of patients and bowel and bladder symptoms in about half patients. But there is a significant incidence of recurrent
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tethering of the cord in adults
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You have recommended various steps to reduce the likelihood of recurrence, frequent turning post-operatively. I actually like to keep patients prone or semi prone for a couple of weeks after this
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kind of surgery
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using a synthetic material for duroplasty What I mean by traction sutures and the duroplasty is you can't
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the graft up alongside the walls of the
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cavity, the surgical cavity. So the graft is less likely to fall back down onto the area that you've just
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done the phylum section. And as some of you already know, we blood in the subaractide spaces, greatest enemy leads to scarring and further adhesions.
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So this is our experience finally at UCLA, 30 patients between Dr. Hollies, Dr. Lewis, and my cases. And as you can see, we too had the largest number where people who had some fat component to
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the phylum, spina bifida, terminal syrings, And, uh,
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tumor in two patients, and most of our patients were primary cases, but we did have some who had a history of spina bifida or had a previous resection of a lipoma or scar tissue.
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And the majority had a low-lying conus at L3-4 or L4 and some even more than that, but occasionally you find some up higher, particularly with tumors or
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with fatty infiltration.
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In our series, the majority of patients presented first with a bowel or bladder problems. A good number of them had weakness and pain, which was either in the low back or in the lung bar region or
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occasionally headache in one patient, sensory impairment was seen in
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And on examining these patients, sensory deficit was the most common finding, weakness or atrophy. Reflex, absence of reflexes I think is very important in often overlooked sign. And sometimes
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you've had patients who had a dermal sinus excised in infancy or who have a little hairy patch
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as we know
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And this is what we did. Deep bulking of lipoma,
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resecting tumors, assess,
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phylum resected in 11 and phylum cut in two. And there's some controversy as to whether there's a benefit to resecting a portion of the phylum. In my own mind, I always think that if you take a
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segment segment of the final object.
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not only is it useful for histology and interest, but it also,
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and I may be wrong in this, reduces the likelihood of re-tettering because you have less of an element that can float around and attach itself somewhere.
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I'm going to defend all the others. All of the post-smile of the dingus hills re-teathering, but how can a phylum section re-teather? If it pops, when you do this,
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you'd like to see it ascend and all that, how can it re-teather just not even in the same neighborhood? It doesn't make sense. Re-teathering doesn't mean that it re-teathers in the same exact same
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area. And it just means that
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whatever is left at the tip of the cord can attach itself. And I think that if there's a lot of blood that isn't cleaned up before a dural closure, you can see how that little tail can attach itself
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to the blood clot and the blood clot organizes and
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That's my way of conceptualizing that.
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Well, yeah, I don't, I haven't seen any evidence for
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this because, I mean, among other things, the initial operation, the reoperation, mostly aren't done in the same place, you know, same facility and, but it's a good question and And, but I
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think
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it's also true that the court doesn't retract to the same degree in every patient in whom you cut the file and when I, as I say in my naive way of thinking about this, if you leave less of a tail
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it's less likely to reattach itself And that question has not been studied
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as far as I
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know
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This was. And just to focus on the question of retraction, it was seen in a number of patients, but not in everybody
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And
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these were our post-aloperative results, and you can see that
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all three major manifestations pain, violent, violent problems, and lower 70 weakness, alternate to improve, although some patients don't change, and a very small number get worse and don't have
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an explanation as to why some people get worse other than if the phylum is surrounded by functioning nerve roots and they're either retracted or damaged in the course of the dissection you can see how
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patients might be worse.
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This corresponds also with the experience of other people like Arnold Manizi's, again, pain
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improves in majority,
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motor and sensory deficits followed by the functional, tend to improve in the majority of patients. And
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in Beni Iskondar's experience as well. So we are right in there with other major reports And these were the trends, which I thought were of interest.
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The best results were seen in patients who had a fatty phylum or had a tumor. Best overall results in terms of pain I'm glad to promise and weakness.
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I mentioned briefly, subtraction, osteotomy. I don't know whether any
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of you have ever seen it, but I'm told that it is a formidable procedure. But in desperate situations where
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particularly at UCSD was years ago many who James Dr. Hector be the lipoma of defunding should, how complete remain some questions So procedure formidable indeed a is and it it doing his videos of
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seen and I've this done also, who has Cornell, Dr. Nicholas man a there's sheet. And surgery in general article an of a subject was And this consider to something, it is file of the explorations
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more or had one who've people.
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cautioned against being overly aggressive because the lipoma may have nerve roots attached or may even be infiltrated by nerve roots and some of the poorer outcomes he thought were related to being
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overly aggressive in trying to resect the lipoma.
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And we've already touched on the question whether
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resecking a part of the phylum has a prognostic value, a question which has not been studied. And
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should we insert a durograft? Well, sometimes the situation lends itself best to primary closure. But if you do put in a graft, tint it up and away from the area of decompression And I think
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that's,
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we've talked about this, and as I said to you before, The treatment for occult tested cord is currently subject of discussion. But Dr. Klinger advocates
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sectioning
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So, just to summarize, very common cutaneous manifestations and pain is most common, fatty tissue and infiltration is most common,
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decreased elasticity or tightness of the phylum is common to all types and pain response better than other symptoms. And the earlier the better to treat best when treated under five years of symptoms.
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Thank you
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Thank you for giving that great talk and for everybody here, whenever Dr. Bastorff is giving a lecture or a talk, make sure you listen because there's so much knowledge, there's so much
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information that he's accrued over so many years and there's never going to be anybody like him ever again and he has a treasure for all of us and we should all, every breath, everything he does,
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watch and listen to him pay attention to. Thank you, I hope there'll be, I hope there'll never be another person be coming, I do think. So
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I do have a question for you Rick, in terms of, you know, one of the things about these procedures that can be a little disappointing is the post-operative imaging, you know, we're used to seeing
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imaging, you know, tumors, tumors gone, or QIRA, serences gone, or better at times the. post-doctoral imaging for tethered cord is not as spectacular. And as Marvin described, and as you
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describe commonly when you section a phylum, you see it zip up out of your field, which is one of the technical nuances to make sure you coagulate it well and cut it a little bit at a time. Because
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once you cut it, it goes. And you will not find it. And if it's still bleeding up above, you're in a world of hurt now. You've got to do another laminectomy and everything. But despite seeing
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that action on your post-operative MRIs, it doesn't show as much of an ascent as you would have thought commonly. And so any thoughts about that in general and how - 'cause then the radiologist says,
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well, it's not significantly different. The patient says, you know, not significantly different. How do you kind of reconcile those things? And particularly with their exam being better, as
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you've seen.
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Yeah, I think that's a very good question. And I think one of the things that,
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again, I have not seen any. a valuable discussion in literature.
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If you think of
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a 10 year old having the final transected, it's had, this individual has had 10 years
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of, has had 10 years of a
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lower cord. But if you think of somebody 35 years old, I think some changes including alterations in the dentate ligament from years of
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low position
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are permanent. I don't, I think that
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the dentate ligaments, for example, become less elastic and have been stretched for 30 years. It's unreasonable to expect that they're going to say, Oh, thank you.
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and we can now get back to our normal position. So I think
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that the age of the individual as well as the severity of displacement may play a role in that. I don't know the exact answer. Another way to think about it, if you did this operation in the
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patient in the supply position, like they are an MRI scan, it may not go up the same way it goes up in surgery, but it's a very memorable position. So if you were able to scan a patient on the
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Wilson frame or wherever you used it, you may see it in the OR. So it's just could be a position issue. Yeah, I mean, because certainly me, if you think about it, just one almost, kind of
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moderate size, one almost can move from where you level, you see them on the MRI, you get the OR, it could be up a fair amount, or down a little bit. So I think that's probably a good part of
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the MRI that there's a little more mobility there Thank you.
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you're sectioning the violin. Is there like the best level or location to do so? I imagine, you know, too high up near the bonus as bad or where it's like you're preferred. That's a good
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interesting question. Where does the best level to section the violin? I like to have in my exposure a clear segment of the violin I mean, it's very often, as you know, prominent blood vessel on
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the surface of the violin. I don't want to get too close to the
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comments, but
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I don't know that there's any benefit in terms of likelihood of re-tethering to section it higher or lower, interesting question. Anyway, Aria? to a great talk. I have a question for you for that.
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controversial,
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those controversial patients where you see symptoms of tethered cord but with a normal position of the conist.
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What do you think the role of actually finding a fatty filum is? So if you don't, so presence versus absence of having fat in the filum, does that? Having a fatty filum? In that area?
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I think that's an entirely possible, yeah, I think it's, and I would, I would, you know, doing the exposure and sectioning it is a relatively straightforward procedure with minimal
38:59
post-operative consequences have done properly and I would give the patient a benefit of a diagnosis
39:06
Have you seen that? We treated that condition, or do you call? I don't recall that any of the cases that I reviewed, fall into that category. I mean, we, we all know and will not mention that
39:22
this has been done to access by some people in pediatric populations and has led to unnecessary procedures I think for the residents, you should understand it when you look at the literature, the
39:38
history of this and it's interesting that you mentioned key already because. same goes for CRV zero, where there was this one center who was cleaning up, and one of the criteria for diagnosis was
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cash pay or good insurance
39:57
because it only existed in people who could pay.
40:03
Isn't that true? No, it's totally true. It's totally true, and so it's one of those diagnoses that the symptoms are non-specific. It can be caused by a lot of things and can lead to this. I'm
40:18
gonna go in there and do this like even at Brown. They, I mean, look at Dr. Bastor's and Dr. Hollies and new series here. If there's 30 cases over 24
40:31
years, that's because we have a very well-selected group patients who have been, you know, exquisitely studied. and you have really good outcomes. Versus if you open it up and all of a sudden say,
40:46
well, I'm going to start doing this because any child with your recess, I'm going to do a tethered court. You could make a lot of money, but you can, you know, and at Brown, I think this
40:59
diagnosis is the most profitable diagnosis at Brown. And you wonder if there's other secondary forces here leading to this excessive, or because they do, probably 30 cases, or every six months,
41:15
or something. Oh, yeah, yeah. But there's one thing that I did not mention, which I've certainly advocated, as some of you know. I think imaging the patient in the supine and prone position is
41:32
helpful from a diagnostic point of view, because if the court is truly tethered, As in the case that you mentioned of fatty infiltration. of the found if the cord remains dorsal when the patient is
41:47
prone, that would strengthen my argument for intervening surgically.
41:56
Sure, do you think there might be any role for e-lastography in this patient? So the spinal cord, or do you know if that's been done? I don't know whether it's done,
42:07
yeah. Just to go back to Dr. Burstein, I have a comment. I think the key to this, you know, selecting those more challenging patients actually gonna be the clinical history. Not so much the
42:20
imaging. So if you have a patient with, you know, clear bilateral like, especially in the pediatric population, it's rare to have like a child complaining back pain or like pain, any bladder
42:34
disturbance. To me, you almost need an
42:38
explanation I mean, it's one thing that says a surgeon. You know, I don't think this is it, and you send them off to be this of sort of, you know, seeing a whole bunch of other people. But if
42:48
you have that triad or the more of those symptoms that you have, I think that pushes you over to do especially an operation that has, I'd say minimal risk, right? If done properly, you really
43:00
shouldn't get a tethered cord, you shouldn't get, you know, raccoon anditis and all that. So
43:06
I think, you know, it becomes more challenging when all the symptoms are subjective, right? So pain or, you know, we do have a spine of bifida clinic where we send them for pre-surgical bladder
43:18
evaluation and that way you get some objective data. Say there are some signs of neurogenic bladder or their bladder capacities change or some, and it helps us so we don't just rely on a, you know,
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on a subjective report. But I will also say, you know, it's definitely a selection bias, right? If we say we're only gonna treat, ones that are clear cut and yes they do well hence no one else
43:41
does well that that's not really a comparison so hence the need for this trial that's happening because it is controversial it is I've tended to give those patients a benefit of that we recently did a
43:54
patient who was sort of had was tool walking and and was basically told your your kids just like this actually it was in the normal position had some patio filtration we did the surgery and two weeks
44:08
post stop she's walking better so we'd have those rare cases that shouldn't be the norm that shouldn't be the you know reason to sort of offer everyone's surgery but you got to take the time I think
44:17
more important than just staring at the imaging here is getting a good history and physical death.
44:26
By the way I did pass out some selected references for people who want to read about this lot been written about this but Some of the papers are not cited very often like the ones from a corner and
44:38
solving.
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Okay, thank you very much.
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neurosurgery.
46:47
The Medical News Network is a network
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also owned by the foundation and it brings truthful medical and science news to the people in the world.
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Thank you