Spina Bifida Occulta (SBO) is often found when someone gets an X‑ray or another picture of their spine. The name means “hidden split spine.” In SBO, one or more back bones do not close all the way. But there is no opening or sac on the back like in other types of Spina Bifida. The skin covers the area, and the spinal cord and nerves are usually normal.
About 1 in 10 adults have SBO, and most never have symptoms. Many people do not know they have it until an X‑ray shows that one or more bones look different. SBO is seen more often in children (as many as half), but in most cases the bones finish closing as the child grows.
SBO does not cause back pain. If it is found by accident during imaging, there is usually no need for more tests or worry unless there are other problems with the nerves, bones, or skin.
When to Be Concerned About Spina Bifida Occulta (SBO)
Some people with SBO or other spine problems may have signs of a serious issue like a tethered spinal cord, which means the spinal cord is being stretched. Signs to watch for include:
- Pain that moves down one or both legs
- Weakness in one or both legs
- Numbness or strange feelings in the legs or back
- Trouble with balance or walking
- Problems going to the bathroom, like trouble potty training
- Curved spine (scoliosis)
- Feet that are shaped or turned in a different way than normal
If someone has any of these signs, they should see a doctor right away. To check for problems, doctors may do an MRI or, for newborns, an ultrasound of the spine.
Most people with Spina Bifida Occulta (SBO) don’t have any problems
But some forms of SBO can cause serious issues. These may need treatment, so talk to a doctor if you notice signs of tethered cord, including:
- Lipomyelomeningocele and lipomeningocele – The spinal cord is stuck to a lump of fat under the skin.
- Thick or fatty filum – Everyone has a string-like piece called the filum that connects the bottom of the spinal cord to the tailbone. If the filum is too thick or filled with fat, it can pull on the spinal cord.
- Split spinal cord (diastematomyelia or diplomyelia) – The spinal cord splits into two parts, often around a piece of bone or tough tissue. These cords may be attached to a fatty lump or thick filum that pulls on them.
- Dermal sinus tract – A small tunnel of tissue connects the spinal cord to the skin on the back. This can pull on the spinal cord and also let germs in, which may lead to infection.
What If There Are No Leg Pain or Nerve Problems?
Even if a person has no leg pain or other nerve problems, there can still be signs of a spinal cord issue. These signs often show up on the skin of the lower back and may include:
- A small patch of hair
- A fatty lump
- A red or purple spot (this could be a harmless bump made of blood vessels, called a hemangioma)
- A dark spot or birthmark (Note: blue-gray marks called “Mongolian spots” are common and not a sign of a problem)
- A deep hole or tunnel in the skin, especially if it’s above the top of the butt crack—this is called a skin tract or sinus and can look like a deep dimple
- A light-colored spot on the skin
If your child has any of these skin signs, they should be checked by a doctor.
Low Back Pain and Spina Bifida Occulta (SBO)
Low back pain is very common. Spina Bifida Occulta (SBO) does not usually cause back pain. Many people with back pain happen to have SBO, but it isn’t the reason for the pain.
People with or without SBO are treated the same way for back pain. No special treatment is needed just because someone has SBO.
Back pain is usually treated with:
- Staying active
- Gentle exercise
- Heat (like a heating pad)
- Over-the-counter medicine (like ibuprofen or acetaminophen)
Resting too much can actually make things worse. Low-impact activities like walking, swimming, yoga, or bike riding can help. If the pain is strong or lasts a long time, physical therapy or chiropractic care may help.
Physical therapists can teach safe exercises and how to avoid more pain in the future.
When to see a doctor
If you or your child has back pain along with any of the following, they should see a doctor:
- Pain that spreads to the legs
- Numbness, tingling, or weakness in the legs
- Trouble with balance or walking
- Problems with peeing or pooping
Who can help:
- Primary care providers – first stop for back pain and testing
- Physical Medicine and Rehabilitation providers – doctors who treat pain and joint problems without surgery
- Spine surgeons – may help if surgery is needed
- Neurologists – help with nerve problems like numbness or weakness
By Brad Dicianno, MD, Robin Bowman, MD, and Christopher Standaert, MD, 2022
This information does not constitute medical advice. As specific cases may vary from the general information presented here, the Spina Bifida Association advises readers to consult a qualified medical or other professional on an individual basis.
