Spina Bifida Repair - Congenital Spine Surgery

Closing the back takes two hours. The kidneys take the next fifty years.

Families arrive asking after the operation. Surgery, the part we are most certain of, is also the smallest of the three things that will decide how this child lives. Prevention comes before it and the bladder comes after it, and this page gives all three their proper weight without dwelling on the hours in the operating room.

What the repair is, and what it is not

Around the third or fourth week of a pregnancy, before most women know they are pregnant, a flat sheet of cells rolls into a tube that becomes the brain and the spinal cord. Where that tube fails to seal at its lower end, the cord stays open to the outside. Skin, muscle and bone never form over it. Nothing grows back later. By the time the baby is born, the nerves that should control the legs, the bladder and the bowel have spent five months exposed to amniotic fluid and rubbing against the wall of the uterus, and a good deal of the damage has already been done. Repair means covering that opening. The surgeon separates the flattened neural tissue from the skin it has fused with, tucks it back into the spinal canal, and rebuilds the layers over it one at a time, watertight. Done well, it protects what remains and it stops infection reaching the brain through an open wound. Done badly, it leaks, and a leak in the first days of life is a serious problem. The operation takes roughly two hours and it is the most predictable part of this entire condition, which is precisely the reason so much of this page sits elsewhere.

The forms, and where the defect sits

One name covers several quite different conditions, and the differences decide almost everything that follows.

This table scrolls sideways on a narrow screen. Swipe or drag to see every column.

Why the level matters more than the size

Parents look at the opening and judge it by how big it looks. Surgeons look at how high up the spine it starts, because every nerve leaving the cord below that point is affected and every nerve above it is spared. A defect at the bottom of the lumbar spine leaves hip and knee power intact and takes the feet and the bladder, so most of those children walk. One at the level of the chest takes the legs entirely. Size tells you how much skin has to be borrowed to close the wound. That is a plastic surgery question. Level tells you what the child will be able to do at ten, and the two have very little to do with each other, which is the first thing we explain when a family sends us photographs instead of imaging. There is a second reason the level dominates every conversation, which is that it also predicts the bladder, the bowel, the likelihood of a curved spine and the amount of bracing a child will wear, so a single number on a report quietly sets the agenda for twenty years of appointments. Get it in writing.

The vitamin that prevents most of it

Here is the most effective treatment for this condition, and nobody performs it in an operating room.

Canada made folic acid fortification of flour and cereal products compulsory in 1998, and researchers then counted neural tube defects across seven provinces, covering 1.9 million births between 1993 and 2002. Before fortification the rate ran at 1.58 per thousand births. After full fortification it ran at 0.86, a fall of 46 percent across all neural tube defects and 53 percent for spina bifida specifically. The provinces that had started with the worst rates improved the most, and the long standing gap between eastern and western Canada very nearly disappeared. Half of these children were simply never conceived with the condition, and the intervention was flour. Fortification is now compulsory in some eighty countries and absent in most of the rest, including a great deal of Europe and much of Asia, which is the single clearest reason the rate of this condition varies so widely from one country to another without the genetics varying anything like as much. Geography does a lot of the work here.

Why telling women to take a tablet does not work as well

Timing defeats advice. The neural tube closes by the fourth week of pregnancy, which for many women is before a missed period and long before a first appointment, so a supplement started when the test turns positive has already arrived too late to do the thing it is for. A woman who plans her pregnancy and starts folic acid three months ahead gets the full benefit. Roughly half of pregnancies worldwide are not planned that way. Fortification works because it does not ask anyone to plan anything. Bread reaches everybody. For any family who has already had one affected child, the recurrence risk rises and the recommended dose rises with it, to a much higher daily amount begun well before conception and continued through the first trimester. That conversation belongs with an obstetrician and not with us. We raise it at the first consultation anyway, because the family in front of us is frequently weighing another pregnancy and nobody has mentioned it.

Finding it before birth

Most cases are picked up at the mid pregnancy ultrasound, somewhere between 18 and 22 weeks, and often by the signs in the head rather than by the defect in the back. A skull that has taken on a lemon shape, a cerebellum pulled into a banana curve, small ventricles that have started to enlarge, and every one of those is easier to see than the defect itself, which is why sonographers are trained to recognize them before they go looking down the spine, since the back of a moving fetus is harder to see than the skull is. Once the suspicion exists, three things settle it. A detailed ultrasound by somebody who does this work weekly, to establish the upper level of the defect and whether the legs are moving. Fetal magnetic resonance imaging, which shows the hindbrain and the ventricles far better and answers questions the ultrasound leaves open. Genetic testing too, because a small proportion of these babies have a chromosomal abnormality that changes the whole picture, the whole prognosis and the whole conversation a family is about to have.

Families who reach us at this stage usually want two questions answered before anything else. Will my baby walk, and will my baby need a device for fluid. The honest answers are that the level of the defect gives a decent estimate for the first and no promise, and that the second depends on the hindbrain and on where the repair is done, which the next two sections cover. What we will not do at this stage is offer a number the imaging cannot support, because a family planning a delivery abroad deserves a range and the reasoning behind it rather than a reassuring figure that turns out later to have been invented to make the conversation easier.

The closure itself, hour by hour

A baby born with an open back is nursed face down or on one side from the delivery room onward, with the defect covered by a sterile saline dressing and nothing allowed to dry on it. Latex is kept away from the child from the first minute, since a large share of these children develop a latex allergy over the years and early avoidance reduces it. Antibiotics start immediately. Nothing waits for morning. The head is measured and an ultrasound looks at the ventricles. Closure happens within the first day or two. Under the microscope the surgeon frees the flattened plate of neural tissue from the skin fused to its edges, rolls it into something closer to a tube, and returns it to the spinal canal. The covering layer is then rebuilt and closed watertight, the muscle and fascia come across over that, and the skin closes last, sometimes needing flaps rotated in from either side when the defect is wide. Nerves are monitored throughout. Nothing here is rushed, because the single thing that most often sends these babies back to the operating room in the first two weeks is a leak through a closure that was not quite tight.

Then the waiting starts. The baby lies flat on the front for several days while the wound seals, feeding is established, and the head circumference is plotted daily, since roughly four in five of these babies go on to need something done for fluid and the need declares itself in the first weeks. A back that healed beautifully and a head that has started climbing off the chart is the commonest story of the second week of life, and it is expected rather than a sign that anything went wrong. Parents should be told this before it happens. Hearing on day one that four babies in five will need a second procedure lands very differently from discovering it on day twelve, when it arrives looking like a complication nobody warned you about.

Discharge comes when the wound is dry, feeding works, and the fluid question has an answer. Two to four weeks covers most babies.

Before birth or after, side by side

Everyone once assumed the damage was complete the moment the tube failed to close. A trial conducted across three centers tested that assumption by randomly assigning women carrying affected babies either to closure before 26 weeks of pregnancy or to standard closure after delivery, and it was stopped early because the babies operated on before birth were doing better.

This table scrolls sideways on a narrow screen. Swipe or drag to see every column.

Read down the first four rows and the case looks overwhelming. Read the last two and it becomes a judgment call. Which is what it actually is.

Whether the advantage lasted

Early results in surgery have a habit of shrinking. The trial reported its motor findings at 30 months, which is early enough that a skeptic could reasonably expect the gap to close once all the children were older and walking demands had risen. So the investigators went back and examined them between the ages of five and ten.

What 154 children looked like at school age

Examiners who did not know which operation a child had received assessed self care, mobility and walking. Children repaired before birth managed self care better, walked 10 meters a second faster, moved with better gait quality and could perform harder mobility tasks. Half of them counted as community walkers against a quarter of the other group. Most striking of all, they were substantially less likely to be functioning below the level their anatomy predicted, meaning fewer of them had lost ground the defect itself did not account for. The advantage seen at two and a half years had not faded by ten.

That is an unusually durable result and it deserves saying plainly. The benefit of operating before birth, for the children who get it, is real, measurable years later, and not an artifact of early enthusiasm.

What the mother pays

Now the other side. It gets less attention than it has earned.

Operating on a fetus means opening the uterus of a woman who is not herself ill. She undergoes a general anesthetic, a hysterotomy and months of restricted activity, and she accepts a clearly increased chance of delivering early and a measurable chance that the uterine scar will thin or separate at delivery. That last item matters beyond this pregnancy. It constrains how she can deliver in future and, for some women, how many more children she can safely have. The benefit accrues to the baby. The risk accrues to her. Medicine contains very few situations shaped like that, and the shape of it is the reason this decision cannot be reduced to the table in the previous section. A counseling conversation that does not spend as long on the mother as it does on the baby has not been done properly, and where a woman decides the trade is not one she wishes to make, that is a legitimate decision and nobody should be made to feel otherwise.

Who can be offered repair before birth

Criteria are narrow and they exist for good reasons. A confirmed myelomeningocele with the upper level of the defect sitting within a defined range that the assessing center will state precisely. A hindbrain already pulled down, which is the sign that the fluid problem is coming. Gestational age inside the window, since the operation happens before 26 weeks. A single pregnancy, normal chromosomes, no other major abnormality, and a mother whose own health, uterus and body weight make the surgery reasonable, and only a very small number of centers perform the operation at all, with the assessment that decides eligibility taking days rather than an afternoon. Distance complicates all of this for families abroad, since the assessment, the surgery and the delivery all have to happen at the same institution, which means relocating for the remainder of the pregnancy. Few families can arrange that in the two or three weeks the window leaves them.

Families who arrive after the window has closed

Most of the families who write to us are already past it, and some of them arrive carrying guilt over a choice that was never actually available to them. Closure after birth is in no way second best treatment. It remains the standard operation worldwide, the one the trial compared against, and the one that the overwhelming majority of children with spina bifida have had, so where the window has gone the useful questions all point forward, to the fluid, the bladder and the spine. All three carry the next twenty years of decisions, they are the ones a family has genuine influence over, and they are the subject of everything below this line.

The bladder, read honestly

Adults living with spina bifida rarely name the legs as the thing that dominates daily life.

The nerves controlling the bladder leave the cord at its very lowest end, below almost every defect, so bladder involvement is close to universal in the open form. A bladder that cannot empty and cannot relax generates high pressure. High pressure drives urine back up toward the kidneys, kidneys exposed to that year after year fail, and for most of the twentieth century kidney failure, and not the spinal defect, was what killed people with this condition in early adulthood. Nothing about that process announces itself. A bladder generating dangerous pressures produces no pain, no fever and no visible sign until the kidneys have already lost function that will not come back, and that is why the surveillance described in the next section runs on a calendar and not on symptoms, and why families who skip a scan because the child seems well are taking a risk they have not been told the size of.

What the trial found when it looked at bladders at age seven

156 children were assessed. Fewer of those repaired before birth were on catheters, 62 percent against 87, and far more of them passed urine voluntarily, 24 percent against 4. Take that as the good news, because it counts. The rest of the picture did not move. Rates of bladder augmentation surgery, vesicostomy and urethral dilation were the same in both groups, and the pressure studies and the kidney and bladder scans showed no meaningful difference at all. The investigators wrote plainly that urological outcomes alone should not be the reason a family chooses surgery before birth.

Smaller series have reported more encouraging bladder findings after repair before birth, including normal function in around half of a small group at two years. Those numbers deserve watching and they do not carry enough weight to promise anybody anything, since the randomized data with the longest follow up says the kidneys end up in a similar place either way. What protects kidneys is what has always protected them, and the next section is about that.

Kidneys, and the routine that changed survival

Nothing in the history of this condition improved life expectancy as much as a plastic tube and a schedule did.

• Emptying the bladder on a clock. A clean catheter passed every few hours keeps the bladder from filling to the pressures that damage kidneys, and parents are taught it in infancy and children take it over themselves as they grow.
• Medication to keep the bladder relaxed. Drugs that stop the bladder muscle contracting against a closed outlet lower the pressure between catheterizations.
• Pressure studies, repeated. A urodynamic test measures what the bladder is actually doing, and comparing this year against last year catches deterioration long before a symptom appears.
• Surgery when the routine stops working. Enlarging the bladder with a patch of bowel, or building a channel to catheterize through, for the children in whom pressure stays dangerous.

What the schedule looks like in practice

Kidney and bladder ultrasound and a pressure study in the first months, then imaging at intervals through childhood with pressure studies repeated whenever anything changes, whether that is a new leak between catheters, a fever from the urine, a foot that has started turning in, or a curve appearing in the spine. Every one of those can mean the cord has tethered, and the bladder is frequently the first place tethering shows itself, before any weakness is visible. Continence itself becomes its own goal somewhere around school age, separate from the kidneys, since a child who leaks is a child who is treated differently in a classroom, and the catheter routine that protects the kidneys is also what makes a dry school day possible.

Families who travel for surgery need this arranged at home, since none of it can be done from another country, so we write the schedule out, name the tests, and address it to the doctor who will carry it.

The hindbrain, the fluid and the curving spine

Three more things travel with the open form, and families are rarely told all three at once.

• The hindbrain sits too low. Leaking fluid through the open back pulls the cerebellum and brainstem down into the top of the neck during pregnancy, and in a minority this compresses structures that matter for swallowing and breathing, most dangerously in the first months of life. Closing the back before birth reverses it in many babies.
• Fluid backs up. That displaced hindbrain obstructs the drainage route, so roughly four in five babies repaired after birth need either an endoscopic opening or a valve and tube. Repair before birth cuts that to around two in five.
• The spine curves. Muscles pulling unevenly on a spine whose bony arches never formed produce scoliosis in a large share of children with high defects, appearing during growth spurts and managed with braces, with surgery for the curves that keep progressing.

Each of those belongs to a different specialist, which is the practical reason this condition needs a team and not a lone surgeon. A unit that cannot name the urologist, the orthopedic surgeon and the rehabilitation physician who will see your child is offering an operation and calling it a service. Ours are named in the written plan, with the dates they will see the child during the admission, so that a family flying home has met everyone who will still be involved a decade from now.

Tethering, and walking

Scar forms wherever a cord has been operated on, the child grows taller, and the cord does not lengthen to match. Tension builds across years and then something changes. What changes first is usually small, and the three cards below are what we ask families to watch for and report without waiting for a scheduled appointment.

Releasing the cord means reopening the old scar, separating the cord from the wall it has stuck to under the microscope with the nerves monitored, and closing again watertight, and the operation stops progression far more reliably than it reverses what has already been lost, so the value of it depends almost entirely on how early somebody noticed. Children released after months of unreported weakness get less back than children released after weeks. Walking itself follows the level first and everything else second. Children with defects low in the lumbar spine or in the sacrum very often walk independently. Higher defects mean braces, a frame, or a wheelchair for distance with walking kept for the house, and none of those outcomes is a failure of the operation, since physical therapy, orthotics that fit properly and released tethering all help a child reach the ceiling their anatomy allows. Nothing raises that ceiling after birth. So the aim we describe to families is the highest function the anatomy permits, held for as long as possible, which is a smaller promise than the one some centers make and it has the advantage of being one we can keep. Smaller promises hold.

Cost, timing and flying home

Length of stay depends on which operation brings you. A newborn closure means two to four weeks in the country, because the wound has to seal and the fluid question has to be answered before anyone can plan a journey. Untethering in an older child runs to around two weeks. A procedure for fluid alone, whether endoscopic or a valve, is usually one week.

Fitness to fly turns on pressure inside the head and on the state of the wound. A baby whose head circumference has settled onto a line, whose wound is dry, who is feeding and whose scan is satisfactory travels safely. One whose fluid question is still open does not, and we say so even when the tickets are booked, because the risk sits in being far from a neurosurgical unit more than in the cabin. Four things move the cost. Which operation is performed and how long the surgeon expects to be in the room. Nights in neonatal or pediatric intensive care. Whether a device for fluid goes in during the same admission. And whether urology and orthopedics are involved while you are here, which for this condition they frequently are. All of that goes into a written quote once the imaging has been read, and we publish no figures on this page, since a number attached to an operation nobody has assessed would be a guess dressed up as a price.

Follow up once you are home costs nothing. Send the scans, send the pressure studies, send the head measurements, and we will read them and write back for as long as you want us involved.

Coming here with a baby

A newborn admission runs for weeks, so the arrangements below matter more here than they would for a short procedure.

Spina bifida repair FAQ

Most first messages contain at least one of the following.

References

1. Adzick NS, Thom EA, Spong CY, Brock JW, Burrows PK, Johnson MP, et al. A randomized trial of prenatal versus postnatal repair of myelomeningocele. New England Journal of Medicine. 2011;364(11):993-1004.
2. Houtrow AJ, MacPherson C, Jackson-Coty J, Rivera M, Flynn L, Burrows PK, et al. Prenatal repair and physical functioning among children with myelomeningocele. A secondary analysis of a randomized clinical trial. JAMA Pediatrics. 2021;175(4):e205674.
3. Brock JW, Thomas JC, Baskin LS, Zderic SA, Thom EA, Burrows PK, et al. Effect of prenatal repair of myelomeningocele on urological outcomes at school age. Journal of Urology. 2019;202(4):812-818.
4. De Wals P, Tairou F, Van Allen MI, Uh SH, Lowry RB, Sibbald B, et al. Reduction in neural-tube defects after folic acid fortification in Canada. New England Journal of Medicine. 2007;357(2):135-142.
5. Horst M, Mazzone L, Schraner T, Bodmer C, Mohrlen U, Meuli M, Gobet R. Prenatal myelomeningocele repair. Do bladders better. Neurourology and Urodynamics. 2017;36(6):1651-1658.
6. Moldenhauer JS, Adzick NS. Fetal surgery for myelomeningocele. After the Management of Myelomeningocele Study. Seminars in Fetal and Neonatal Medicine. 2017;22(6):360-366.