Spina Bifida

Definition

Spina bifida is a type of birth defect called a neural tube defect. In spina bifida, a baby's spine does not close completely during early pregnancy. Spina bifida can begin to develop in a fetus even before the mother knows she is pregnant.

Spina Bifida

Nucleus factsheet image

There are three kinds of spina bifida:

Occulta

The least severe form.
No symptoms.
Small defect in one or more vertebrae.
Spinal cord and nerves are normal.
Usually no complications.

Meningocele

A cyst made up of membranes, which surround the spinal cord, protrudes through the open part of the spine.
Spinal fluid can leak out.
The cyst can be surgically removed.
Development after surgery is usually normal.

Myelomeningocele

This is the most severe form of spina bifida.
A cyst made up of membranes, nerve roots, and sometimes the spinal cord itself comes through the open spine.
Substantial problems including paralysis and incontinence [2] of bowel and bladder may occur. These symptoms are frequently not cured by surgery.
Myelomeningocele is frequently accompanied by changes in the spinal cord that prevent cerebrospinal fluid from circulating normally around the brain [3]. These changes may require additional surgery to prevent increased pressure in the spinal fluid, which goes into the cranial cavity, thus leading to a serious condition called “ hydrocephalus. [4] ” This causes pressure on the brain [3] itself.

Causes

The cause of spina bifida is unknown. As with many other congenital abnormalities, there is a strong hereditary component. Many studies show that mothers’ diets lacking a vitamin called folic acid are significantly associated with the development of spina bifida.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Most risk factors for spina bifida are related to the mother's health [5]. Risk factors 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 is a sac filled with fluid leading out from the baby's spine. The 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 [3] (hydrocephalus)
Scoliosis [6]
Latex allergy [7] (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 possibility of spina bifida can be evaluated before birth using a blood test called the maternal serum alpha-fetoprotein (MSAFP) screening test. If this test predicts a high risk of neural tube defects, your doctor will perform two more tests:

Amniocentesis [8] —This involves insertion of a needle into the uterine cavity to remove a sample of amniotic fluid. Levels of MSAFP and other substances in the amniotic fluid are measured.

Ultrasound [9] —This is a test that uses sound waves to examine structures inside the body. In this case, the fetal spine is examined.

Prenatal diagnosis can help you and your doctor plan for a specially equipped delivery room for quick surgery after birth. It can also give you some time before delivery to learn more about spina bifida and how to care for your child.

After birth, meningocele and myelomeningocele are usually apparent on physical exam. Many tests will be required to determine the extent of internal deformities to the skeleton and nervous system. Function of the kidneys [10], which often become damaged, also needs to be monitored closely.

Most children with occulta spina bifida will never be diagnosed because this condition rarely causes any symptoms and has few complications. Occulta spina bifida may be discovered during routine medical [11] examination or following x-rays [12] of the spine.

Treatment

Occulta spina bifida requires no treatment.

Meningocele spina bifida is treated with surgery to remove the cyst, after which the child usually develops normally.

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

Surgery

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

Physical Therapy

Therapists teach parents [13] how to exercise [14] the infant's legs and feet. Walkers, braces, and crutches will often be required for mobility.

Ongoing Treatment

Complications of spina bifida can be ongoing and extensive. It will be important for you to work [15] with a team of doctors who can 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 and talk to your doctor if you have any of the risk factors listed above.

RESOURCES:

March of Dimes
http://www.modimes.org [16]

Spina Bifida Association of America
http://www.sbaa.org [17]

CANADIAN RESOURCES:

Sick Kids (The Hospital for Sick Children)
http://www.sickkids.ca/ [18]

Spina Bifida and Hydrocephalus Association of Canada
http://www.sbhac.ca [19]

References:

American Academy of Pediatrics website. Available at: http://www.aap.org/ [20] .

March of Dimes website. Available at: http://www.modimes.org [16] .

Last reviewed October 2007 by Robert E. Leach, MD [21]

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical [11] advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health [5] provider prior to starting any new treatment or with any questions you may have regarding a medical [11] condition.