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'' is a
Latin term which means "split spine" and describes
Birth Defect s caused by an incomplete closure of one or more vertebral arches of the
Spine , resulting in malformations of the
Spinal Cord . The spinal membranes and spinal cord may protrude through the absence of
Vertebral arches (called clefts). These malformations fall into three categories: ''spina bifida occulta'', ''spina bifida cystica (myelomeningocele)'' and ''meningocele''.
Spina bifida is a type of
Neural Tube Defect . Neural tube defects can usually be detected during pregnancy by
AFP Screening or a detailed fetal
Ultrasound . Spina bifida may be associated with other malformations as in dysmorphic syndromes, often resulting in spontaneous miscarriage. However, in the majority of cases spina bifida is an isolated malformation. Spina bifida has varying prevalence in different human populations. This and extensive evidence from mouse strains with spina bifida suggests a genetic basis. As with other human diseases such as
Cancer ,
Hypertension and
Atherosclerosis (coronary artery disease), spina bifida likely results from the interaction of multiple genes and environmental factors. Despite much research on spina bifida we still do not know what causes the majority of cases. Nevertheless, there is substantial evidence supporting a significant protective effect of
Folic Acid (0.4
Mg per day) when taken by women early in pregnancy. It is important to note that spina bifida occurs by the 4
th week of pregnancy before many women will be aware of a pregnancy, thus it is generally recommended that women of child-bearing age take a folic acid supplement (most multivitamins contain 0.4mg folic acid) if they are sexually active.
Genetic Counseling and further
Genetic Testing , such as
Amniocentesis , may be offered during the pregnancy as some neural tube defects are associated with genetic disorders such as
Trisomy 18 .
The most common locations of the malformations are in the
Lumbar and
Sacral areas. The lumbar nerves control the
Muscle s in the
Hip ,
Leg ,
Knee and
Foot , and help to keep the body erect. The sacral nerves control some of the muscles in the
Feet ,
Bowel and
Bladder and the ability to have an
Erection . Some degree of impairment can be expected in these areas.
"Occulta" is the Latin for "hidden."
This is a mild form of spina bifida. There is no opening on the back, but the outer part of some of the vertebrae are not completely closed. The split in the vertebrae is so small that the spinal cord does not protrude. The skin at the site of the
Lesion may be normal, or it may have some hair growing from it; there may be a dimple in the skin, or a
Birthmark . People with this form may have
Incontinence , slight ambulatory problems, and slight loss of sensation.
In this, the most serious form, the meningeal membranes that cover the spinal cord and part of the spinal cord protrude through a cleft, forming a sac or
Cyst , and are clearly visible. In developed countries, this opening is
Surgically repaired shortly after birth. Additionally, in the U.S. the National Institute of Child Health and Human Development (NICHD) is currently involved in a fetal intervention study (
MOMS ).
The sac or cyst not only contains
Tissue and
Cerebrospinal Fluid but also
Nerve s and part of the spinal cord. The spinal cord is damaged or not properly developed. As a result, there is usually some degree of
Paralysis and loss of sensation below the damaged vertebrae. The amount of disability depends very much on where the spina bifida is and the amount of nerve damage involved. Many children and adults with this condition experience problems with bowel and bladder control. In approximately 90% of the people with myelomeningocele,
Hydrocephalus , extra fluid in the
Ventricles of the brain, will also occur.
In this, the least common form, the outer part of some of the vertebrae are split and the
Meninges are damaged and pushed out through the opening, appearing as a sac or cyst, which contains both the meninges and cerebrospinal fluid. The nerves are not usually badly damaged and are able to function, therefore there is often little disability present. There are usually no negative long-term effects, although problems have been known to arise.
Spina bifida is caused by the failure of the
Neural Tube to close during
Embryonic development. Normally the closure of the neural tube occurs around the thirtieth day after
Fertilization . However, if something interferes and the tube fails to close properly, a neural tube defect will occur. Neural tube defects include the conditions of
Anencephaly ,
Encephalocele , and spina bifida.
Spina bifida occurs in the first month of pregnancy, often before the woman knows that she is pregnant.
Spina bifida does not follow direct patterns of heredity like
Muscular Dystrophy or
Haemophilia . Studies show that a woman who has had one child with a neural tube defects such as spina bifida, have about a 3% risk to have another child with a
Neural Tube Defect . This risk can be reduced to about 1% if the woman takes high doses (0.4mg/day) of folic acid before and during pregnancy.
It is known that women taking certain medication for
Epilepsy and women with insulin dependent diabetes have a higher chance of having a child with a neural tube defect. It is also more common among those of
Gaelic descent than any other ethnic group.
Spina bifida results in varying degrees of paralysis, absence of skin sensation, incontinence, and spine and limb problems depending on the severity and location of the lesion damage on the spine. In very rare cases, cognitive problems also result.
Most babies born with the condition will need surgeries to correct spinal, foot or leg problems,
Shunt surgery to drain fluid from the brain, application of techniques to control bladder and bowel function (such as self-
Catherization or
Diaper s), and braces or other equipment to assist in walking.
Tethered Cord , with symptoms such as lower body pain, leg weakness, incontinence,
Scoliosis , numbness, is a common problem associated with spina bifida. Indeed 100% of spina bifida myelomeningocele patients have Tethered Cord, caused by the spinal cord damage when it is repaired by surgery soon after birth, and the resulting natural scar tissue buildup. However many do not show symptoms of Tethered Cord until later in life or never at all. Before
MRI s were invented, Tethered Cord could only be detected through symptoms or surgery and therefore those born before the invention of the MRI, and without symptoms, may not know they have it, or even what it is. If, or when, symptoms show up later in life it can often be a difficult process to discover the correct diagnosis, by which time further damage has been done.
According to the Spina Bifida Association of America (
SBAA ), over 73% of people with spina bifida develop an allergy to
Latex , ranging from mild to life-threatening. The common use of latex in medical facilities makes this a particularly serious concern.
There is no cure for spina bifida. To prevent further drying and damage of the nervous tissue and to prevent infection, doctors operate as soon as possible to close the opening on the back, but there is no operation that can fix damaged nerves. During the operation, the spinal cord and its nerve roots are put into place and covered with skin.
Doctors are now experimenting with and evaluating the efficacy of .
In
Canada , spina bifida occurs in about one in every 1000 births.
In Western
Australia , up until
1996 around 2 children in every 1000 were born with a neural tube defect. Since 1996, as a result of the folic acid campaign, the figure has dropped to 1.3 children per 1000 births.
In the
United States , spina bifida occurs in about 7 out of 10,000 live births. More children in the U.S. have spina bifida than have
Muscular Dystrophy ,
Multiple Sclerosis , and
Cystic Fibrosis combined.
Doctors and
Scientist s have found that
Folic Acid can help to prevent spina bifida. It is recommended that all women of childbearing age and women planning to become pregnant should take at least 0.4 mg/day of folic acid from at least one month before
Conception , and at least 1 mg/day of folic acid during at least the first three months of pregnancy. Women who have already had a baby with spina bifida or other type of neural tube defect should take extra folic acid: 4 mg/day. As yet it is unknown how or why folic acid helps to prevent spina bifida.
Sources of folic acid include:
Whole Grain s, fortified
Breakfast Cereal s, dried
Bean s,
Leaf Vegetable s,
Fruit s.
People of note born with spina bifida:
