Spina bifida can occur in different types: spina bifida occulta, myelomeningocele (my-uh-lo-muh-NING-go-seel) or the very rare type meningocele (muh-NING-go-seel).

Spina bifida occulta

“Occulta” means hidden. It’s the mildest and most common type. Spina bifida occulta results in a small separation or gap in one or more of the bones of the spine (vertebrae). Many people who have spina bifida occulta don’t even know it, unless the condition is discovered during an imaging test done for unrelated reasons.

Myelomeningocele

Also known as open spina bifida, myelomeningocele is the most severe type. The spinal canal is open along several vertebrae in the lower or middle back. The membranes and spinal nerves push through this opening at birth, forming a sac on the baby’s back, typically exposing tissues and nerves. This makes the baby prone to life-threatening infections and may also cause paralysis and bladder and bowel dysfunction.

Signs and symptoms of spina bifida vary by type and severity, and also between individuals.

Myelomeningocele. In this severe type of spina bifida:
The spinal canal remains open along several vertebrae in the lower or middle back

Both the membranes and the spinal cord or nerves protrude at birth, forming a sac

Tissues and nerves usually are exposed, though sometimes skin covers the sac

Causes
Doctors aren’t certain what causes spina bifida. It’s thought to result from a combination of genetic, nutritional and environmental risk factors, such as a family history of neural tube defects and folate (vitamin B-9) deficiency.

Complications

Spina bifida may cause minimal symptoms or minor physical disabilities. But severe spina bifida can lead to more significant physical disabilities. Severity is affected by:

• The size and location of the neural tube defect
• Whether skin covers the affected area
• Which spinal nerves come out of the affected area of the spinal cord

This list of possible complications may seem overwhelming, but not all children with spina bifida get all of these complications. And these conditions can be treated.

Walking and mobility problems. The nerves that control the leg muscles don’t work properly below the area of the spina bifida defect. This can cause muscle weakness of the legs and sometimes paralysis. Whether a child can walk typically depends on where the defect is, its size, and the care received before and after birth.

Orthopedic complications. Children with myelomeningocele can have a variety of problems in the legs and spine because of weak muscles in the legs and back. The types of problems depend on the location of the defect. Possible problems include orthopedic issues such as:
Curved spine (scoliosis)
Abnormal growth
Dislocation of the hip
Bone and joint deformities
Muscle contracture

Bowel and bladder problems. Nerves that supply the bladder and bowels usually don’t work properly when children have myelomeningocele. This is because the nerves that supply the bowel and bladder come from the lowest level of the spinal cord.

Accumulation of fluid in the brain (hydrocephalus). Babies born with myelomeningocele commonly experience accumulation of fluid in the brain, a condition known as hydrocephalus.

Shunt malfunction. Shunts placed in the brain to treat hydrocephalus can stop working or become infected. Warning signs may vary. Some of the warning signs of a shunt that isn’t working include:
Headaches
Vomiting
Sleepiness
Irritability
Swelling or redness along the shunt
Confusion
Changes in the eyes (fixed downward gaze)
Trouble feeding
Seizures

Infection in the tissues surrounding the brain (meningitis). Some babies with myelomeningocele may develop meningitis, an infection in the tissues surrounding the brain. This potentially life-threatening infection may cause brain injury.

Tethered spinal cord. Tethered spinal cord results when the spinal nerves bind to the scar where the defect was closed surgically. The spinal cord is less able to grow as the child grows. This progressive tethering can cause loss of muscle function to the legs, bowel or bladder. Surgery can limit the degree of disability.

Sleep-disordered breathing. Both children and adults with spina bifida, particularly myelomeningocele, may have sleep apnea or other sleep disorders. Assessment for a sleep disorder in those with myelomeningocele helps detect sleep-disordered breathing, such as sleep apnea, which warrants treatment to improve health and quality of life.

Skin problems. Children with spina bifida may get wounds on their feet, legs, buttocks or back. They can’t feel when they get a blister or sore. Sores or blisters can turn into deep wounds or foot infections that are hard to treat. Children with myelomeningocele have a higher risk of wound problems in casts.

Other complications. More problems may arise as children with spina bifida get older, such as urinary tract infections, gastrointestinal (GI) disorders and depression. Children with myelomeningocele may develop learning disabilities, such as problems paying attention, and difficulty learning.

Spina bifida treatment depends on the severity of the condition. Spina bifida occulta often doesn’t require any treatment at all, but other types of spina bifida do.

Surgery before birth. Nerve function in babies with spina bifida can worsen after birth if spina bifida isn’t treated. Prenatal surgery for spina bifida (fetal surgery) takes place before the 26th week of pregnancy. Surgeons expose the pregnant mother’s uterus surgically, open the uterus and repair the baby’s spinal cord. In select patients, this procedure can also be performed less invasively with a fetoscope through ports in the uterus.

Surgery after birth. Myelomeningocele requires surgery. Performing the surgery early can help minimize the risk of infection associated with the exposed nerves. It may also help protect the spinal cord from more trauma.

During the procedure, a neurosurgeon places the spinal cord and exposed tissue inside the baby’s body and covers them with muscle and skin. At the same time, the neurosurgeon may place a shunt in the baby’s brain to control hydrocephalus.