Spina Bifida – Open Spine

Because the child’s spine is not fully closed due to spina bifida, nerve damage may occur starting from the affected area of the back. Depending on the severity of the malformation, this leads to various postnatal, lifelong impairments. Spina bifida is therefore characterized primarily by three key symptoms:

• limited mobility or even complete paralysis of the legs,
• Difficulty emptying the bladder and bowel
• as well as the development of hydrocephalus.

Today, specialized clinics offer the option of performing surgery on affected fetuses while they are still in the womb to prevent nerve damage from progressing during pregnancy. The University Hospital of Zurich (USZ) is one of Europe’s leading centers in this field. Learn more here.

What is spina bifida?

Spina bifida develops as early as the third to fourth week of pregnancy. During this early stage, two tissue folds (neural folds) in the embryo close and fuse to form a precursor to the spinal canal, known as the neural tube. The spinal column with the spinal cord and the brain develop from it. If the neural tube does not close completely, the spinal canal formed by the vertebrae remains open – there is then a gap at the back of the affected vertebral arches. This has led to the colloquial term “open back”. Literally translated, however, “spina bifida” means “split spine.” The opening usually extends across several vertebral bodies.

According to estimates, about one to two out of every 1,000 unborn babies in Switzerland are affected by spina bifida. Depending on the type of spina bifida and the extent of nerve damage, those affected may exhibit symptoms of varying severity. The consequences of the disease can therefore vary widely. Therefore, if spina bifida is suspected, it is important to accurately diagnose the type of lesion as well as any impairments that are already apparent.

The two main forms: spina bifida occulta and spina bifida aperta

Spina bifida occulta

This is the mildest form of spina bifida. It often causes no symptoms and therefore frequently goes undetected for a long time. The term “occulta” (“hidden”) refers to the fact that, although the vertebral bodies are not closed, they are completely covered by skin, thus protecting the spinal cord from injury.

Spina bifida aperta

Spina bifida aperta is the open form of spina bifida that is visible from the outside. It affects not only the vertebrae, which protect the spinal cord, but also the overlying skin. The spinal canal contains nerve tracts that are surrounded by cerebrospinal fluid (CSF) and protected by meninges. In the case of spina bifida aperta, these meninges can shift outwards from the spinal canal and form a sac-like protrusion. Medical professionals therefore distinguish between different types:

• If the protrusion is covered by skin and lined with the meninges, and contains only cerebrospinal fluid, the spinal cord itself may remain intact. In this case, the condition is called a meningocele.
• When layers of connective tissue (meninges) and parts of the spinal cord and nerves protrude outward through the spinal canal and lie exposed on the surface of a sac-like protrusion (cele), this condition is called a myelomeningocele (also known as a meningomyelocele ).
• If the spinal cord is completely exposed but there is no protrusion (cele), the condition is called myeloischisis.

What causes spina bifida?

It is not clear why the neural tube does not close properly at the beginning of a pregnancy when the embryo is still tiny. However, there are a few indications of factors for an increased risk of disease. These include:

• Folic acid deficiency: Folic acid is a vitamin that is important for cell division and blood formation; it is also called vitamin B9. If there is an insufficient intake of folic acid or a disruption in folic acid metabolism during the first few weeks of pregnancy, the likelihood of spina bifida developing increases.
• Heredity: As open backs occur more frequently than average in some families, it is assumed that genetic causes play a role in the development of spina bifida. If one child already has the disease, the risk of spina bifida in the second newborn increases by around 40 percent. Since not all genetic factors that could lead to spina bifida have been identified yet, genetic testing before pregnancy (preimplantation genetic diagnosis) is not possible. Couples who have had a child with spina bifida in a previous pregnancy are advised to seek early ultrasound screening at an experienced center to check for signs of spina bifida.
• Epigenetics: It is not only changes in the genes themselves that may contribute to the development of spina bifida—changes in the mechanisms that regulate these genes also play a role. The collective term for these chemical regulatory mechanisms is the epigenome. It can be influenced by environmental factors and diet, among other things. The exact mechanisms are currently being studied.
• Maternal conditions: gestational diabetes, alcohol abuse, obesity (severe overweight)—these are also risk factors that increase the likelihood of spina bifida in the unborn child.
• Medication: If a pregnant woman takes certain medication for epilepsy – for example the active ingredient valproic acid – this can also have a negative impact on the early development of the embryo and increase the risk of spina bifida.

Symptoms: How does spina bifida manifest itself?

The spinal cord is the “data line” between the brain and the body. If it is no longer intact, signals are disrupted and various areas of the organism no longer function properly.

If an unborn child has a form of spina bifida in which the spinal cord protrudes from the open vertebral bodies and lies exposed, the baby’s movements and irritation from the amniotic fluid can cause irreversible damage to the nerves, which is responsible for the various characteristic symptoms of spina bifida. In addition, the protrusion of the spinal cord causes tension on the cerebellum, which has a negative effect on the circulation of cerebrospinal fluid. Depending on the severity of these mechanical influences on the nervous tissue and the cerebellum, children exhibit impairments of varying degrees at different times. In most children with spina bifida, the lower part of the back is affected. The main areas affected in these cases are the legs, feet, bladder and bowel. The higher up the back a spinal gap is located, the more bodily functions may be affected.

In spina bifida, three clinical signs in particular stand out; these are referred to in medicine as “key symptoms”:

• Loss of sensation or paralysis, especially in the lower extremities
• Incontinence (loss of bladder and bowel control)
• Hydrocephalus (an accumulation of cerebrospinal fluid in the brain due to excessive buildup and poor circulation)

People with a severe form of spina bifida are therefore dependent on professional and personalized support. This multidisciplinary care involves not only obstetricians and surgeons, but also specialists in urology, orthopedics, physical therapy, and developmental medicine. This comprehensive care begins after birth and continues throughout a person’s life. You can learn more about the comprehensive care provided to children with spina bifida by visiting the link to the Spina Bifida Center (SBZ) at the University Children’s Hospital of Zurich: Spina Bifida Center (SBZ).

Diagnosis: How Is Spina Bifida Diagnosed?

If you are pregnant, you want to know as early as possible whether your unborn child is healthy and how it is developing. Although spina bifida develops as early as the fourth week of pregnancy, a reliable diagnosis is not yet possible at that stage. Spina bifida is rarely diagnosed during the first or early second trimester.

Spina bifida is typically detected during the second ultrasound exam (also known as organ screening, which takes place between the 19th and 22nd weeks of pregnancy). During this detailed ultrasound examination, in addition to assessing the child’s growth and checking all organ systems, the back is also examined thoroughly. If spina bifida has been diagnosed or is suspected, a magnetic resonance imaging (MRI) scan may be performed to obtain additional information about the type of spina bifida and the apparent impairments. Magnetic resonance imaging is safe for both the mother and the baby during pregnancy, as it does not involve X-rays.

Treatment: How Can Spina Bifida Be Treated?

Since an open spine develops as early as the first few weeks of embryonic development, spina bifida cannot be cured, even with an early diagnosis. The goal of the treatment options available to date is therefore to protect the nerve tissue from irreversible damage. In addition to treatment during pregnancy, postnatal management of the malformation is also possible.

Spina Bifida Surgery Before Birth

In certain cases, the open spinal defect can be surgically repaired even in unborn babies. In prenatal surgery, the spinal cord is first repositioned to its “natural position” and then carefully enclosed in several layers of protective tissue. This allows the delicate spinal cord to be protected from further damage at an early stage. Skills that are still present at the time of the prenatal surgery can be preserved, and in most cases, the child can be spared surgery immediately after birth. Prenatal surgery also has a positive effect on the circulation of cerebrospinal fluid, so that affected children are less likely to develop hydrocephalus requiring treatment.

For more than 15 years, the University Hospital of Zurich, in collaboration with the University Children’s Hospital of Zurich, has been performing prenatal surgeries to treat spina bifida. This makes it one of the most experienced centers in the world and a leader in open fetal surgery in Europe. About one-third of the children live without impairments after the procedure; others often have fewer disabilities and, as a result, a better quality of life than children who underwent surgery only after birth. However, if spina bifida is treated surgically while the baby is still in the womb, the risk of preterm birth is higher than with a postnatal procedure (after birth). For this reason, the USZ offers comprehensive aftercare planning for affected families.

Spina Bifida Surgery After Birth

In some cases, spina bifida is not treated surgically during pregnancy, but only after birth. There may be various medical reasons for this. In most cases, postnatal surgery for open spina bifida is performed on the first day of life. The newborn’s exposed spinal cord should be protected as quickly as possible, and infections should be prevented. Postnatal surgery cannot reverse nerve damage that occurred during pregnancy.

Aftercare: Living Independently Despite Spina Bifida

To enable children with spina bifida to live as independently as possible, medical professionals from a wide range of disciplines work closely together.

To prevent uncontrolled and involuntary urination (incontinence), for example, those affected can empty their bladders in a controlled manner by using catheters, thereby preventing accidental wetting or urinary tract infections. Through targeted support from physical and occupational therapists and the use of orthopedic aids, children can learn to move as freely and independently as possible, even if they have nerve damage.

Even in cases of hydrocephalus (commonly known as “water on the brain”), a small surgical procedure can be performed to create a shunt to drain the cerebrospinal fluid, allowing the child’s brain to develop without excessive intracranial pressure. The goal of all these measures and of the treatment team is to provide children and their families with long-term support and enable them to lead self-determined and self-sufficient lives.

Despite some of the complaints and limitations that an open back entails, the quality of life of those affected does not necessarily have to suffer with good care and treatment. This is shown by quality-of-life studies in which affected children and adolescents were asked about their quality of life. Here, more than 64 percent of the children reported a good quality of life, and as many as 30 percent of the children and adolescents reported a very good quality of life.

The Spina Bifida Center (SBZ) at the University Children’s Hospital of Zurich offers expert counseling and comprehensive follow-up care for infants, children, and adolescents with spina bifida.

Prevention: Can spina bifida be prevented?

Since the exact causes of spina bifida are not fully understood, there are only limited options for prevention. However, an adequate intake of folic acid before and during pregnancy can reduce the risk: Up to 70 percent of spina bifida cases can be prevented if the expectant mother takes folic acid as early as three months before conception. A daily dose of 400 micrograms of folic acid is recommended. In any case—and especially if you have any pre-existing conditions—be sure to seek advice on your folic acid dosage or any necessary adjustments to your medications well before becoming pregnant.