Spina bifida occulta is common. A recent study suggests that 17 per cent of people whose spines have been examined have spina bifida occulta.
Even though these people have a very slightly increased chance of a slipped disc, very few people with spina bifida occulta will ever have any problems because of it. If a person has no symptoms from spina bifida occulta as a child, then it is unlikely that they will have any as an adult.
Most people will not even be aware that they have spina bifida occulta unless it shows up on an X-ray which they have for some unrelated reason. It is usually just a small part of one vertebra low in the back which is missing.
However, for some people (about 2 per cent of those who have spina bifida occulta) there can be other problems. These problems arise because there are other things involved around the area where the vertebra has not formed properly.
For this small percentage of people the problem with the spine can also be more extensive than just a small piece of missing bone. More than one vertebra can be involved and these vertebrae may be malformed.
Some of the other things that can occur around this site and affect a person's functioning include the following.
To avoid confusion, the term often used for spina bifida occulta with these associated problems is occult spinal dysraphism (OSD).
In addition to these structures which are usually hidden from view, there are a number of signs which may appear on the skin (cutaneous signatures) and give a clue to the underlying problems with the central nervous system. These signs can appear on their own but quite often they appear in combination.
Here are some common ones.
Symptoms can include the following.
For parents of young children with these problems, it is important for you to consider the following.
Back pain is very common in our society. Many people suffer back pain for a great variety of reasons and those reasons may be present with or without OSD.
For a person experiencing back pain it is appropriate to look at what other factors may be influencing the pain. The fact that a person has OSD cannot be changed, but many other factors can.
It is important to be aware of good back care, e.g. correct lifting methods, good posture, appropriate exercise etc. A physiotherapist can give advice in these areas.
Some of the symptoms of a tethered spinal cord are:
All of these symptoms can have other causes and should be investigated by a doctor. If it is warranted, an operation can be performed by a neurosurgeon to ‘detether’ the spinal cord. This procedure will usually not restore lost functioning, but in most cases it is able to halt the worsening of symptoms.
In Australia, neural tube defects affect one pregnancy in 500. It is well known that the risk of a child being born with a neural tube defect such as spina bifida is increased if there is a close family history of neural tube defects. What is not so well known, though, is that the risk is also increased if the close family history includes OSD.
The risk of a child being born with a neural tube defect (anencephaly, spina bifida) is the same irrespective of whether the close family history includes anencephaly, spina bifida or occult spinal dysraphism. For a first-degree relative, i.e. a parent or sibling, the risk is about one in 25.
Even though more research needs to be undertaken to clarify the picture, it seems that the close family history of OSD predisposes to an increased risk of a child being born with any neural tube defect, not just OSD. That is, the increased risk is for the whole spectrum of neural tube defects, not just OSD.
Thus people who have occult spinal dysraphism or with a close family history of it should seek the advice of a genetic counsellor if they are contemplating having children.
Folic acid is a water-soluble vitamin found in many fruits, leafy green vegetables, cereals and legumes. A diet rich in folate (the naturally occurring folic acid) or the taking of folic acid supplements of 0.5 mg each day for the month before and the first 3 months of pregnancy can reduce the risk of neural tube defects by up to 70 per cent.
However, people with a close family history of neural tube defects, including OSD have a higher risk of having a child with a neural tube defect. Women in high-risk groups like this need to take a higher dose (5 mg) of folic acid. Higher dose folic acid supplements are available from pharmacies.
NOTE: It is impossible to get 5 mg of folic acid from eating foods high in (or even fortified with) folate. It is known that in our society, only half of all pregnancies are planned. By the time a woman discovers that she is pregnant, any problem with the development of the neural tube will already have taken place. By then it is too late for folic acid to have any effect. So, it is advisable for all women who could become pregnant to take a folic acid supplement.
Last Reviewed: 17 September 2007