Spina bifida

Spina bifida occurs when a baby’s spine and spinal cord do not develop properly before birth. Learn about the different types of spina bifida, their causes, how they are diagnosed and the health issues that can occur in children with this diagnosis.

Key points

Spina bifida means the spine and spinal cord have not formed completely in the fetus before the baby is born.
There are four common types of spina bifida: myelomeningocele, meningocele, lipomyelomeningocele and spina bifida occulta.
What causes spina bifida is unknown but spina bifida and other neural tube defects are less likely to occur when pregnant individuals get enough folic acid before and during the early stages of pregnancy.
Spina bifida may result in a number of health issues including varying degrees of paralysis and loss of function and sensation in the legs, as well as bowel and bladder problems, and learning challenges.

Introduction

What is spina bifida?

The spinal cord is a thick bundle of nerves that carries messages between the brain and the rest of the body. It floats in a liquid called cerebrospinal fluid (CSF). This liquid nourishes and protects the brain and spinal cord. The CSF is covered by a lining made of three thin layers called the meninges. This lining is normally protected by the bones of the spine (the vertebrae).

In people with spina bifida, the bones that protect the spinal cord have not formed completely while the baby is developing in the mother's womb. This leaves the lining, the CSF and the spinal cord unprotected. This happens very early in pregnancy.

Spina bifida can happen anywhere along a baby's back between the neck and the hips. It happens most often in the lower back. This area is called the lumbar or lumbosacral spine.

Children with spina bifida may have health problems because of this condition. They may experience changes or loss of feeling in their legs, have decreased movement of their legs or not be able to move their legs at all. They may also have problems with their bladder and bowel function, and have learning challenges.

About 2.6 in every 10,000 babies are born with some form of spina bifida.

The four main types of spina bifida

There are four main types of spina bifida:

spina bifida occulta
lipomyelomeningocele
meningocele
myelomeningocele

"Meningo" refers to the lining of the vertebral canal. "Myelo" refers to the spinal cord itself. "Cele" means a sac or something bulging out.

Vertebrae, spinal cord and meninges in normal spine, and illustrations of spines with the four forms of spina bifida

Spina bifida occulta

Spina bifida occulta is the mildest form of spina bifida. It occurs when a small section of the outer part of one or more of the vertebrae (the bones of the spine) has not completely closed, leaving an opening. In this type of spina bifida, the spinal cord and its coverings (the meninges) are usually not damaged and they do not protrude or bulge through the opening. There may be a dimple, tuft of hair, birthmark or fatty bulge at the site of the defect. This type of spina bifida may not be detected before birth. Many people may have this type of spina bifida and not be aware of it.

Lipomyelomeningocele

A lipomyelomeningocele is a form of spina bifida where the outer part of one or more of the vertebrae has not completely closed, leaving an opening. Some abnormal fatty tissue pushes through the opening and may cause compression of the nerves or abnormal formation of the spinal cord.

Meningocele

A meningocele is a more severe form of spina bifida. It occurs when the outer part of the vertebrae has not completely closed, leaving an opening. The meninges (covering) are pushed through the opening to form a sac. The spinal cord is not pushed into the sac, so the nerves may not be as severely affected. This sac is often covered with skin.

Children with a meningocele may have normal movement and normal feeling in their legs and feet.

Myelomeningocele

A myelomeningocele is the most severe form of spina bifida. It occurs when the outer part of the vertebrae has not completely closed, leaving an opening. With a myelomeningocele, both the covering of the spinal cord (the meninges) and the spinal cord itself are pushed out through the opening. Usually they protrude into a covered, fluid-filled sac that has a very thin membrane (not covered by skin). Because part of the spinal cord bulges into the sac, the spinal cord fails to develop properly and nerves are damaged. Most children with a myelomeningocele will have difficulty with movement and feeling in their legs and feet.

Causes, risk factors and prevalence

Diagnosis

Treatment

Complications

Health problems linked to or caused by spina bifida

Every child with spina bifida is different with their own medical, mobility and learning needs. Some children may only be mildly affected while others may have more significant disabilities. Being born with spina bifida can bring life-long challenges. Your child’s health-care team will work together with you to help your child achieve their greatest potential.

The following health issues are common for children with spina bifida.

Hydrocephalus

Over 80 percent of babies born with spina bifida, primarily those with myelomeningocele, will also have hydrocephalus. Hydrocephalus is an abnormal build-up of CSF in the ventricles inside the brain, causing enlargement of the ventricles. Surgery may be required to treat the build-up of CSF.

Chiari malformation

Nearly all babies born with myelomeningocele have a Chiari malformation type 2. This is when the lower part of the brain (the brainstem) sits too low in your child’s upper spine area. Some children with Chiari malformation type 2 may have feeding problems (for example, weak suck when feeding, gagging, choking, trouble swallowing), sleep apnea or weakness of the arms. Surgery may be required to decrease the pressure on the lower part of the brain.

Leg function (movement) and sensation (feeling)

In children with spina bifida, the nerves in the spinal canal are often damaged or improperly formed. This can affect both feeling and movement in the legs. Some children may not be able to feel or move their legs at all, while others can stand and walk (with or without the help of equipment).

Muscles and bones

Muscles and bones may also be affected by spina bifida. For children with spina bifida, damaged nerves may mean they are unable to control their muscles properly. The position of the lesion on the back determines which muscles in the trunk and legs work. Generally, the lower the lesion is on the back, the more likely the muscles in the legs will work.

A baby with spina bifida may be born with clubfoot, this is when the baby's feet are turned in at the ankle.

The baby's hips may also be affected as different muscles may be stronger than others interfering with how the hips move and function. This can cause dislocation of the hip.

Muscles around the spine may also be affected. Any difference in muscle strength can affect the position of the spine and cause an abnormal curve called scoliosis. Children with spina bifida who have muscle and bone issues may need bracing or orthopaedic surgery.

Bladder problems

With spina bifida, the nerves that tell the bladder it is full, and to empty and release urine (pee) are often weak or not working. This means that babies and children with spina bifida may need help to pee and empty their bladder. When your baby is born, a catheter will be put inside their bladder through the urethra every few hours to see if they can pee on their own and empty their bladder. The urethra is the tube inside the body that carries urine from the bladder to the outside of the body. If your baby is unable to fully empty their bladder, they are at risk for urinary tract infections or possibly kidney issues. You may need to learn how to empty your baby’s bladder using a catheter before you can take them home. As children with spina bifida grow, they may also need further bladder testing, medications to help with urinary leaking, or surgery to help control their bladder and their ability to use a catheter by themselves. A member of the urology team will talk to you about this.

Bowel problems

Bowel function is controlled by nerves that are located in the bottom section of the spinal cord. Because of this, many children with spina bifida have differences in bowel function. Constipation is seen in almost all children with spina bifida. If bowel movements cannot be regulated with diet, fluids and toileting routines, other strategies including medications, suppositories, enemas or surgery may be needed.

Latex allergies/sensitivity

Babies with spina bifida have an increased chance of developing a latex sensitivity or allergy. It is important to make sure that products such as gloves, catheters and soothers do not contain latex.

Tethered cord

The spinal cord is normally elastic. In children with spina bifida, the spinal cord can get stuck at the site of the lesion and this is called a tethered cord. It is often stretched over time. That stretch can lead to injury of the spinal cord. Surgery may be required to treat tethered cord if it is causing symptoms.

Learning

Many children with spina bifida have difficulties in specific areas of learning. Your child may or may not have difficulty with some types of learning (such as attention and impulse control, memory, problem solving and visual spatial skills). Special testing by a psychologist may be needed to assess learning challenges. Some children may require educational support strategies to cope with aspects of learning that are difficult for them. It is important to recognize these needs early on to minimize frustration and maximize success at school.

Follow-up care

Resources

Last updated: اکتوبر 25th 2024