Spina Bifida Occulta

It's not uncommon to be diagnosed with Spina Bifida Occulta as an adult. This is considered a mild form of Spina Bifida, but for many, the lack of information, resources, and awareness can cause frustration. Learn about what Spina Bifida Occulta is so you can better advocate for yourself in the healthcare system.

Spina Bifida Occulta is the mildest type of spina bifida. It is sometimes called “hidden” spina bifida. With it, there is a small gap in the spine, but no opening or sac on the back. The spinal cord and the nerves usually are normal. Many times, Spina Bifida Occulta is not discovered until late childhood or adulthood. This type of spina bifida usually does not cause any disabilities.

There are forms of Spina Bifida Occulta that do cause problems. They are:

  • Lipomyelomeningocele and lipomeningocele—this is like a tethered spinal cord, except it is attached to a benign fatty tumor
  • Thickened terminale—the end of the spinal cord is too thick
  • Fatty terminale—there is a fatty lump at the inside end of the spinal cord
  • Diastematomyelia (split spinal cord) and diplomyelia—the spinal cord is split in two, usually by a piece of bone or cartilage
  • Dermal sinus tract (with involvement of the spinal cord) the spinal canal and the skin of the back are connected by what looks like a band of tissue


Signs of Occulta

People can have these forms of Spina Occulta (SBO) even if there is nothing wrong with the spine. However, there can be neurological complications associated with SBO. The most frequently occurring complication is a tethered spinal cord. A tethered cord occurs when the spinal cord (usually at the lower end) is not attached correctly to the rest of the body. The cord gets stretched and damaged.

The signs and symptoms of a possible neurological complication like a tethered spinal cord include:

  • Pain in the back or legs
  • Weakness in the legs
  • Numbness or other changes in feeling in the legs or back
  • Deformed legs, feet and back
  • Change in bladder or bowel function

People who could have a spinal cord problem should see a health care provider right away.

What about people with no signs of a problem?

Eighty percent of those with a spinal cord problem will have skin over the defect with:

  • a hairy patch
  • a fatty lump
  • a hemangioma—a red or purple spot made up of blood vessels
  • a dark spot or a birthmark—these are red and don’t include blue-black marks, called “Mongolian spots”
  • a skin tract (tunnel) or sinus—this can look like a deep dimple, especially if it’s too high (higher than the top of the buttocks crease), or if its bottom can’t be seen
  • a hypopigmented spot—an area with less skin color.

No matter the age, people who have these signs, should see a health care provider who treats the spinal cord. Not every person with a skin defect of the lower back has Spina Bifida Occulta. However, that can only be determined through physical examination and diagnostic tests. This is especially true for those with a sacral dimple. An ultrasound (only for newborns) or magnetic resonance imaging (MRI) may be used to confirm a problem.



 This information does not constitute medical advice for any individual. As special cases may vary from the general information presented here, SBA advises readers to consult a qualified medical or other professional on an individual basis.




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    Level of SB Function

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    Espina Bífida Oculta