Definition

Spina bifida is a type of birth defect. This type is called a neural tube defect. In spina bifida, a baby's spine does not close completely during early pregnancy. It can begin to develop in a fetus before the mother even knows she is pregnant. In some cases, structures that should be in the spinal canal can slip out. The structures affected involved may include:

  • Membranes that surrounds the spinal cord
  • Nerve roots that connect nerves to the spinal cord
  • Spinal cord
  • Vertebra (back bones) may be deformed

Spina Bifida

Spinabifida
© 2009 Nucleus Medical Media, Inc.

There are three kinds of spina bifida:

Occulta

This is the least severe form and can have:

  • No symptoms
  • Small defect in one or more vertebrae
  • Spinal cord and nerves are normal
  • Usually no complications

Meningocele

In this case the membranes poke through an open part of the spine. This forms a cyst. Spinal fluid can leak out. This type can be treated.

Myelomeningocele

This is the most severe form of spina bifida. In this case, the cyst contains membrane, nerve roots, and sometimes the spinal cord. This type can result in severe problems such as:

  • Paralysis and incontinence of bowel and bladder may occur—frequently not cured by surgery
  • Hydrocephalus. —a build up of fluids in the brain that increase pressure on the brain

Causes

The cause is not known. As with many other birth defects, there is a strong genetic factor. Many studies have shown a link between a low folate diet in the mother and birth defects. The low folate diets are significantly associated with spina bifida.

Risk Factors

Factors that increase the risk of spina bifida include:

  • Low maternal blood level of folic acid at the time of conception
  • Family history of spina bifida
  • A mother who had a previous pregnancy with a neural tube defect
  • Mother's race: Hispanic or Caucasian of European origin
  • Certain medications given during pregnancy

Symptoms

The most immediate symptom of meningocele and myelomeningocele:

  • Sac filled with fluid leading out from the baby's spine
  • Spinal cord and tissue may also protrude through the back

Infants and children with spina bifida may experience the following long-term symptoms:

  • Bowel and bladder problems
  • Frequent urinary tract and other infections
  • Learning disabilities
  • Accumulation of fluid in the brain (hydrocephalus)
  • Scoliosis
  • Latex allergy (from frequent surgeries early in life)
  • Inability to walk
    • Muscle weakness and paralysis of the lower extremities
    • Hip dislocation
    • Foot and ankle deformities
  • Many children with myelomeningocele are wheelchair bound

Diagnosis

The chance of spina bifida can be assessed before birth. This process uses a blood test. It is called the maternal serum alpha-fetoprotein (MSAFP) screening test. If the test predicts a high risk of neural tube defects two more tests will be done:

  • Amniocentesis —a needle is inserted into the uterine cavity. A sample of amniotic fluid is drawn out. Levels of MSAFP and other substances in the fluid are measured.
  • Ultrasound —a test that uses sound waves to look at structures inside the body. In this case, the fetal spine is examined.

A diagnosis before birth can help you and your doctor make plans. A special delivery room will help lead to a quick surgery after birth. It can also give you some time before delivery to learn more about this condition and how to care for your child.

After birth, meningocele and myelomeningocele are usually apparent on physical exam. Many tests will be needed. They will help to determine the extent of internal deformities to the bones and nerves. The kidneys can also often become damaged. They will need to be watched closely.

Most children with occulta spina bifida will never be diagnosed. This condition rarely causes any symptoms. It also has few complications. It may be discovered during a routine medical exam. It may also be found following x-rays of the spine.

Treatment

  • Occulta spina bifida requires no treatment
  • Meningocele spina bifida is treated with surgery to remove the cyst

Treatment for myelomeningocele spina bifida is very complicated and may include:

Surgery

Extensive surgery is done on the baby 24-48 hours after birth. During surgery, the nerves, membrane, and spinal cord are put back into the spine. They are then covered with skin. Prompt surgery can prevent further nerve damage. It cannot reverse damage that has already occurred. More serious forms of spina bifida may require more surgeries. They are done throughout childhood.

Physical Therapy

Therapists teach parents how to exercise the infant's legs and feet. Walkers, braces, and crutches will often be needed for mobility.

Ongoing Treatment

Complications of spina bifida can be ongoing and extensive. It will be important for you to work with a team of doctors. They should be able to provide the best care and support for you and your child. Team members may include:

  • Neurosurgeons
  • Orthopedic surgeons
  • Urologists
  • Rehabilitation experts
  • Physical therapists
  • Psychologists
  • Social workers

Prevention

To help reduce the chance that your baby will be born with spina bifida:

  • Supplement your diet with at least 400 micrograms of folic acid every day if you plan to conceive. Supplementation must begin before the baby is conceived and should continue throughout the pregnancy. While a formal vitamin supplement containing folate may be the most reliable method of supplementation, foods with significant quantities of folate include:
    • Leafy green vegetables
    • Orange juice
    • Beans
    • White flour products and cereals fortified with folate
  • Plan your pregnancies . Talk to your doctor if you have any of the risk factors listed above.