Spina Bifida: Symptoms, Causes & Treatment

What Is Spina Bifida?

Spina bifida is a type of neural tube defect where the spine and spinal cord fail to develop properly during the first month of pregnancy. The neural tube, which becomes the brain and spinal cord, does not close completely, leaving a gap in the vertebrae that can expose or damage the spinal cord and nerves.

Spina bifida literally means "split spine" in Latin, referring to the incomplete closure of the vertebral column. This condition develops very early in pregnancy, typically between the 21st and 28th day after conception, often before a woman even knows she is pregnant. The spinal cord and surrounding structures form from a flat sheet of cells called the neural tube, which normally folds and closes to become the brain and spinal cord. In spina bifida, part of this tube fails to close properly.

The severity of spina bifida varies enormously depending on where along the spine the defect occurs and how much of the spinal cord is affected. Defects higher on the spine generally cause more severe problems because more nerves are affected. The condition can range from a minor vertebral abnormality with no symptoms to a significant opening that exposes the spinal cord, causing paralysis and other serious complications.

Understanding the different types of spina bifida is essential for appreciating the range of outcomes. The condition is broadly categorized into open spina bifida, where there is an opening in the back, and closed spina bifida, where the defect is covered by skin. Each type has distinct characteristics, symptoms, and treatment requirements.

Open Spina Bifida (Myelomeningocele)

Open spina bifida, also called myelomeningocele, is the most severe and common form of the condition. In this type, a sac containing the spinal cord membranes, spinal fluid, and often part of the spinal cord itself protrudes through an opening in the baby's back. The spinal cord and nerves in the sac are damaged, leading to some degree of paralysis and loss of sensation below the level of the defect.

Babies born with myelomeningocele require surgery within 24-48 hours after birth to close the opening and protect the exposed tissue from infection. Even with prompt surgery, the damage to the spinal cord and nerves that occurred during pregnancy cannot be reversed. Most children with this form of spina bifida have some degree of leg paralysis or weakness, bladder and bowel control problems, and approximately 80-90% develop hydrocephalus, which requires placement of a shunt to drain excess cerebrospinal fluid from the brain.

Closed Spina Bifida

Closed spina bifida encompasses several types where the spinal defect is covered by skin. The mildest form is spina bifida occulta, meaning "hidden" spina bifida, where there is a small gap in one or more vertebrae but the spinal cord and surrounding membranes are not affected. This form is very common, occurring in about 10-15% of the population, and most people with spina bifida occulta never know they have it because it causes no symptoms.

More significant closed defects include lipomyelomeningocele, where fatty tissue attaches to the spinal cord, and tethered spinal cord, where the spinal cord is abnormally attached to surrounding tissues. These conditions may not be apparent at birth but can cause problems as the child grows and the spine elongates, pulling on the tethered cord. Symptoms may include back pain, leg weakness, changes in bladder or bowel function, and scoliosis.

What Are the Symptoms of Spina Bifida?

Symptoms of spina bifida depend on the type and location of the defect. Open spina bifida causes visible abnormalities at birth, leg paralysis or weakness, loss of bladder and bowel control, reduced sensation, and often hydrocephalus. Closed forms may have no symptoms or cause subtle signs like a dimple, tuft of hair, or birthmark on the lower back.

The symptoms of spina bifida span a wide spectrum, from completely asymptomatic to life-altering disabilities. Understanding these symptoms helps parents, caregivers, and healthcare providers recognize the condition and its complications. The severity and type of symptoms are primarily determined by the size and location of the spinal defect and which nerves are affected.

In general, defects higher on the spine cause more extensive paralysis and dysfunction because nerves that control the legs, bladder, and bowels emerge from the lower spinal cord. A defect in the thoracic (mid-back) region affects more nerves than one in the lower lumbar or sacral region, resulting in more severe disability. However, even people with similar defect locations can have different levels of function due to variations in which specific nerves are damaged.

Early recognition of symptoms and complications allows for timely intervention, which can significantly improve outcomes and quality of life for people with spina bifida.

Symptoms of Open Spina Bifida

Open spina bifida is immediately apparent at birth. The most obvious sign is a sac or pouch protruding from the baby's back, which may be covered with a thin membrane. If the defect is not covered by skin, the spinal cord and nerves may be visible. Babies with open spina bifida typically exhibit several characteristic symptoms from birth:

• Leg paralysis or weakness: Most children have some degree of paralysis below the level of the defect, ranging from mild weakness to complete inability to move the legs
• Sensory loss: Reduced or absent sensation in the legs and lower body, which increases the risk of pressure sores and injuries
• Bladder dysfunction: The nerves controlling the bladder are often affected, leading to urinary incontinence or retention and increased risk of urinary tract infections and kidney damage
• Bowel problems: Constipation and fecal incontinence are common due to impaired nerve control of the intestines and anal sphincter
• Orthopedic abnormalities: Club foot, hip dislocation, and leg length differences are frequently present at birth or develop over time
• Hydrocephalus: Approximately 80-90% of babies with myelomeningocele develop excess cerebrospinal fluid in the brain, causing the head to enlarge

Symptoms of Closed Spina Bifida

Closed spina bifida may not cause any symptoms, particularly in the mildest form (spina bifida occulta). When symptoms do occur, they may not appear until childhood or even adulthood. Signs that may indicate a closed spinal defect include:

• A dimple, tuft of hair, birthmark, or fatty lump on the lower back over the spine
• Back pain, particularly in the lower back
• Leg weakness or changes in walking pattern
• Changes in bladder or bowel control
• Scoliosis (curvature of the spine)
• Foot deformities or leg length discrepancy

Hydrocephalus and Brain-Related Symptoms

Hydrocephalus, commonly called "water on the brain," occurs when cerebrospinal fluid accumulates in the brain's ventricles because it cannot drain properly. This is extremely common in open spina bifida and occurs because of a related brain abnormality called Chiari II malformation, where part of the brain herniates into the spinal canal and blocks fluid circulation.

Signs of hydrocephalus in infants include a rapidly enlarging head, bulging soft spot (fontanelle), irritability, poor feeding, vomiting, and downward gaze of the eyes (called "sunsetting"). If untreated, hydrocephalus can cause brain damage, developmental delays, and death. Most children with hydrocephalus require a shunt, a surgically implanted tube that drains excess fluid from the brain to the abdomen where it can be absorbed.

People with spina bifida and hydrocephalus may experience cognitive effects including difficulties with attention and concentration, executive function problems (planning, organization, and problem-solving), memory challenges, and spatial awareness difficulties. However, many people with spina bifida have normal or near-normal intelligence and can succeed academically and professionally with appropriate support.

What Causes Spina Bifida?

Spina bifida is caused by a combination of genetic and environmental factors that prevent the neural tube from closing properly during the first month of pregnancy. The most significant known risk factor is folic acid deficiency. Other factors include family history, certain medications (especially anti-seizure drugs), diabetes, obesity, and high body temperature in early pregnancy.

The exact cause of spina bifida remains incompletely understood, but research has identified several factors that increase the risk of having a baby with this condition. Neural tube defects like spina bifida result from complex interactions between a person's genes and their environment. Understanding these risk factors is crucial because many of them can be modified to reduce the risk of spina bifida.

The neural tube normally closes between the 21st and 28th day after conception, which is often before a woman knows she is pregnant. This is why prevention measures, particularly folic acid supplementation, must begin before conception to be most effective. By the time most women discover they are pregnant, the neural tube has already closed or failed to close.

Folic Acid Deficiency

Folic acid (vitamin B9) is essential for proper development of the neural tube. Extensive research has proven that adequate folic acid intake before and during early pregnancy can prevent 50-70% of neural tube defects, including spina bifida. This is one of the most significant preventable causes of birth defects.

The body uses folic acid to make DNA and for cell division, which happens rapidly during early pregnancy. Without sufficient folic acid, cells may not divide properly, leading to abnormal development of the neural tube. Because many pregnancies are unplanned, health authorities worldwide recommend that all women of childbearing age take 400 micrograms (0.4 mg) of folic acid daily.

Genetic Factors

Having a family history of neural tube defects significantly increases the risk of having a child with spina bifida. If one parent has spina bifida, or if a couple has previously had a child with a neural tube defect, the risk of having another affected child is approximately 2-3%, compared to about 0.1% in the general population. This suggests that genetic factors play an important role, though the specific genes involved are still being studied.

Research has identified variations in genes involved in folic acid metabolism that may increase susceptibility to neural tube defects. People with certain variants of the MTHFR gene, which is involved in processing folic acid, may have higher folate requirements and increased risk of neural tube defects if their intake is inadequate.

Other Risk Factors

Several other factors have been associated with increased risk of spina bifida:

• Certain medications: Some anti-seizure medications, particularly valproic acid and carbamazepine, significantly increase the risk of neural tube defects. Women who need these medications should discuss alternatives with their doctor before pregnancy
• Diabetes: Women with poorly controlled diabetes before and during early pregnancy have a higher risk of having a baby with spina bifida. Good blood sugar control before conception and throughout pregnancy reduces this risk
• Obesity: Pre-pregnancy obesity is associated with increased risk of neural tube defects. The exact mechanism is unclear but may involve altered folate metabolism
• High body temperature: Fever or use of hot tubs/saunas during early pregnancy may slightly increase risk. Some studies suggest hyperthermia can interfere with neural tube closure
• Ethnicity: The prevalence of spina bifida varies among ethnic groups, being more common in some populations, which may reflect genetic, dietary, or environmental differences

How Is Spina Bifida Diagnosed?

Spina bifida can be diagnosed during pregnancy through prenatal screening tests. These include maternal blood tests measuring alpha-fetoprotein (AFP), detailed ultrasound examination between 18-20 weeks, and amniocentesis. Open spina bifida is usually visible at birth, while closed forms may be discovered through physical examination or imaging studies like MRI.

Early diagnosis of spina bifida is important because it allows families and medical teams to prepare for the baby's care, consider treatment options including fetal surgery in some cases, and make informed decisions. Prenatal screening has become increasingly sophisticated, enabling detection of many cases before birth.

The diagnosis of spina bifida typically involves a combination of screening tests that identify pregnancies at higher risk, followed by diagnostic tests that can confirm the presence and type of defect. Understanding these tests helps expectant parents know what to expect during pregnancy screening.

Prenatal Screening Tests

Maternal serum alpha-fetoprotein (MSAFP) testing is a blood test performed between 15-20 weeks of pregnancy. Alpha-fetoprotein is a protein made by the developing baby that crosses into the mother's bloodstream. In pregnancies affected by open spina bifida, AFP levels in the mother's blood are typically elevated because the protein leaks from the baby's exposed spinal tissue. An abnormal result does not diagnose spina bifida but indicates the need for further testing.

Detailed ultrasound examination, typically performed between 18-20 weeks of pregnancy, can directly visualize the baby's spine and detect most cases of spina bifida. Skilled sonographers look for specific signs including the "lemon sign" (indentation of the skull) and "banana sign" (curved cerebellum) that are associated with spina bifida. Modern ultrasound technology can detect approximately 90-95% of open spina bifida cases.

Diagnostic Tests

If screening tests suggest spina bifida, amniocentesis may be recommended. This procedure involves inserting a needle through the mother's abdomen to collect a sample of amniotic fluid. The fluid is tested for elevated AFP and for acetylcholinesterase, another marker of neural tube defects. Amniocentesis can confirm the diagnosis with high accuracy.

Fetal MRI may be performed to provide more detailed images of the baby's brain and spine. This is particularly useful for planning treatment, including determining whether a baby might be a candidate for fetal surgery. MRI can show the exact location and extent of the defect, the presence of Chiari malformation, and other anatomical details.

Diagnosis After Birth

Open spina bifida is immediately apparent at birth due to the visible defect on the baby's back. The medical team will perform a thorough examination to assess the level and extent of the defect, evaluate neurological function in the legs, and check for associated abnormalities. Head ultrasound is typically performed to assess for hydrocephalus.

Closed spina bifida may not be apparent at birth and might be discovered later during evaluation of symptoms such as back pain, walking difficulties, or bladder problems. Physical examination may reveal skin abnormalities over the spine, and imaging with MRI can confirm the diagnosis and show the extent of spinal cord involvement.

How Is Spina Bifida Treated?

Treatment of spina bifida involves surgery to close the spinal defect (within 48 hours of birth or prenatally in some cases), shunt placement for hydrocephalus, and ongoing multidisciplinary care. Management includes regular monitoring of neurological function, bladder and bowel care programs, physical and occupational therapy, orthopedic interventions, and educational support.

There is no cure for spina bifida, but treatment can significantly improve quality of life and prevent complications. Care for people with spina bifida is complex and requires a team of specialists working together. This typically includes neurosurgeons, urologists, orthopedic surgeons, physical therapists, occupational therapists, developmental pediatricians, and many other professionals.

The goals of treatment are to close any opening in the spine to prevent infection and further damage, manage hydrocephalus, preserve and optimize neurological function, prevent complications such as kidney damage, and support the child's development and independence. Treatment is lifelong, with needs changing as the person grows from infancy through childhood into adulthood.

Initial Surgical Treatment

Babies born with open spina bifida require surgery within 24-48 hours of birth to close the defect. This urgent surgery aims to cover the exposed spinal tissue, reduce the risk of infection (meningitis), and prevent further damage to the spinal cord. The neurosurgeon closes the membranes around the spinal cord and closes the skin over the area. While this surgery cannot restore function lost due to prenatal nerve damage, it protects the remaining nerves.

If hydrocephalus develops, which occurs in most babies with myelomeningocele, a shunt will be placed. A ventriculoperitoneal (VP) shunt is a tube system that drains excess cerebrospinal fluid from the brain's ventricles to the abdominal cavity where it can be absorbed. The shunt includes a valve that regulates flow. Shunt surgery may be performed at the same time as the spinal closure or within the first few weeks of life, depending on when hydrocephalus becomes apparent.

Fetal Surgery

In selected cases, surgery to repair spina bifida can be performed before birth, typically between 19-26 weeks of pregnancy. The landmark MOMS (Management of Myelomeningocele Study) trial demonstrated that prenatal surgery reduced the need for shunting and improved motor outcomes compared to postnatal surgery. However, fetal surgery carries risks including premature birth and maternal complications, so it is only offered at specialized centers and for carefully selected patients.

Fetal surgery involves opening the mother's uterus, closing the baby's spinal defect, and then closing the uterus. The baby continues to develop in the womb but must be delivered by cesarean section. Newer techniques including fetoscopic surgery are being developed to reduce the risks of open fetal surgery.

Bladder and Bowel Management

Most people with spina bifida have some degree of bladder and bowel dysfunction that requires lifelong management. Clean intermittent catheterization (CIC), performed multiple times daily, is the standard method for emptying the bladder. Starting catheterization in infancy and continuing throughout life helps protect the kidneys from damage caused by urinary retention and infections. Some people also take medications to improve bladder function.

Bowel management typically involves a program of scheduled evacuation using dietary modifications, stool softeners, suppositories, enemas, or a procedure called antegrade continence enema (ACE or Malone procedure) where the colon is irrigated through a small opening in the abdomen. The goal is to achieve social continence, allowing the person to participate fully in school, work, and social activities without accidents.

Orthopedic Care

Orthopedic problems are common in spina bifida and may require braces, walkers, wheelchairs, or surgery. Club feet, hip dysplasia, and scoliosis are frequently present. Regular evaluation by an orthopedic specialist helps identify problems early and determine the best interventions. Many children with spina bifida can walk with braces and other assistive devices, though some prefer wheelchairs for efficient mobility.

Rehabilitation and Therapy

Physical therapy begins in infancy and continues throughout life to maximize mobility, strength, and independence. Therapists teach exercises, help with fitting braces and wheelchairs, and work on mobility skills. Occupational therapy focuses on daily living skills, fine motor development, and adaptive techniques for self-care tasks. Many adults with spina bifida live independently with or without assistance.

How Can Spina Bifida Be Prevented?

Folic acid supplementation is the most effective way to prevent spina bifida. All women of childbearing age should take 400 micrograms (0.4 mg) of folic acid daily, starting at least one month before conception and continuing through the first 12 weeks of pregnancy. Women with higher risk factors may need 4 mg daily. Eating folate-rich foods also helps but is not sufficient alone.

Prevention of spina bifida is one of the great public health success stories. Since the connection between folic acid and neural tube defects was established, rates of spina bifida have declined significantly in countries where folic acid supplementation or food fortification has been implemented. The evidence is clear: adequate folic acid intake before and during early pregnancy can prevent the majority of spina bifida cases.

The challenge is that the neural tube closes very early in pregnancy, typically before most women know they are pregnant. This is why prevention must start before conception. Health authorities worldwide recommend that all women who could become pregnant take folic acid daily, regardless of whether they are planning to conceive.

Folic Acid Supplementation

The standard recommendation is 400 micrograms (0.4 mg) of folic acid daily for all women of childbearing age. This can be obtained through a daily multivitamin or a standalone folic acid supplement. Folic acid supplements are inexpensive and widely available without prescription.

Women at higher risk of having a baby with a neural tube defect need higher doses. This includes women who have previously had a child with spina bifida, those who themselves have spina bifida, and those taking certain medications like valproic acid. These women should take 4 mg (4,000 micrograms) of folic acid daily, starting at least one month before conception and continuing through the first three months of pregnancy. This higher dose requires a prescription.

Dietary Sources of Folate

While supplements are the most reliable way to ensure adequate folic acid intake, eating foods rich in folate is also beneficial. Good dietary sources include dark leafy green vegetables (spinach, kale, broccoli), legumes (lentils, beans, peas), citrus fruits and juices, and fortified foods (many breakfast cereals, breads, and pasta are fortified with folic acid). However, dietary folate is not as well absorbed as synthetic folic acid in supplements, so diet alone is usually not sufficient for prevention.

Other Prevention Strategies

Managing other risk factors can further reduce the chance of having a baby with spina bifida:

• Control diabetes: Women with diabetes should work with their healthcare provider to achieve good blood sugar control before becoming pregnant
• Maintain healthy weight: Achieving a healthy body weight before pregnancy may reduce risk
• Review medications: Women taking anti-seizure medications should discuss alternatives with their doctor before pregnancy
• Avoid hyperthermia: Avoiding fever, hot tubs, and saunas during early pregnancy may be prudent
• Genetic counseling: Families with a history of neural tube defects should consider genetic counseling to understand their risks

What Is Life Like with Spina Bifida?

Living with spina bifida requires ongoing medical care and adaptations, but most people lead fulfilling lives. Many adults with spina bifida live independently, work, attend college, have families, and participate fully in their communities. Success depends on comprehensive healthcare, early intervention, appropriate support services, and fostering independence from an early age.

The outlook for people with spina bifida has improved dramatically over the past decades. With modern medical care, approximately 90% of babies born with spina bifida survive into adulthood, and many live well into their 60s and beyond. Quality of life has also improved significantly as treatment approaches have advanced and society has become more accessible and inclusive.

Living with spina bifida involves adapting to various challenges while maximizing abilities and opportunities. The specific experiences vary widely depending on the severity of the condition, with some people experiencing minimal limitations and others requiring more extensive support. Throughout life, people with spina bifida benefit from a supportive network of family, healthcare providers, educators, and community resources.

Childhood and Education

Children with spina bifida attend school alongside their peers, with accommodations as needed. These may include accessible classrooms and bathrooms, extra time for tests, assistance with catheterization, and physical therapy services at school. Many children benefit from individualized education plans (IEPs) that address any learning differences related to hydrocephalus or other factors.

Cognitive abilities in people with spina bifida range from significant learning difficulties to above-average intelligence. Those with hydrocephalus may have specific challenges with attention, executive function, and spatial reasoning, but with appropriate support, most can succeed academically. Early intervention services and educational support are important for maximizing each child's potential.

Adolescence and Transition

Adolescence brings unique challenges as young people with spina bifida navigate identity, independence, and preparing for adulthood. This is a critical time for transitioning from pediatric to adult healthcare providers, learning to manage one's own medical care, and developing skills for independent living. Many teens benefit from programs that teach self-catheterization, medication management, and advocating for their own needs.

Social relationships and sexuality are important topics during adolescence. Most people with spina bifida can have healthy romantic relationships. Fertility may be affected in some individuals, particularly males, but many people with spina bifida become parents. Open communication with healthcare providers about sexual health and family planning is encouraged.

Adulthood and Independence

Many adults with spina bifida live independently, either on their own or with minimal support. They work in diverse careers, pursue higher education, volunteer in their communities, and enjoy hobbies and social activities. Accessibility features in buildings, transportation, and workplaces have made participation in society increasingly possible.

Ongoing healthcare remains important throughout adulthood. Adults with spina bifida need regular monitoring of bladder and kidney function, shunt function if present, skin integrity, and overall health. Finding adult healthcare providers who understand spina bifida can be challenging, and many medical centers are now developing transition programs and adult spina bifida clinics to address this need.

Support and Resources

Connecting with others who have spina bifida through support groups and organizations can be valuable. These connections provide emotional support, practical advice, and advocacy for improved services and accessibility. Organizations like the Spina Bifida Association offer resources, educational materials, and opportunities to connect with the spina bifida community.