Spina bifida

What is spina bifida?

Spina bifida is a term used to describe a condition where the spinal cord, surrounding nerves and or spinal column does not to develop normally during the first 28 days of pregnancy.

The condition can affect the nervous, urinary, muscular and skeletal systems, often causing bowel and bladder complications and weakness and numbness below the spinal defect.

Causes of spina bifida

The causes of spina bifida are unknown, although most experts agree that the condition is probably caused by a combination of environmental, nutritional and genetic factors.

There are different types of spina bifida which include:

• Spina bifida occulta
• Myelomeningocele
• Meningocele

Spina bifida occulta

Spina bifida occulta is a mild type of spina bifida, and is quite common. In this type the opening of the spine is very small. The opening in the spine is covered with skin, so the gap is not visible from the outside.

Spina bifida occulta does not usually cause any symptoms and most people do not know that they have it until they have a back X-ray for an unrelated problem.

Myelomeningocele

Myelomeningocele is the most serious and more common of spina bifidas. In this type the spinal column remains open along several vertebrae. The membranes and spinal cord push out to create a sac in the baby’s back.

Sometimes the sac is covered with membranes called meninges, although it often remains open, leaving the nervous system vulnerable to further complications such as infections. It is estimated that it affects one baby in every 1000 that are born in Britain.

Most babies with myelomeningocele will also develop hydrocephalus, which is a condition where there is excess fluid (CSF) in the brain.

Meningocele

Meningocele is the rarest type of spina bifida. In this type the meninges, the protective membranes that surround the spinal cord, are pushed out between openings in the vertebrae. The membranes can usually be repaired with surgery and often no further surgical treatment is needed.

How is spina bifida diagnosed?

Most cases of spina bifida are found during the routine ultrasound scans that are done at antenatal appointments. It can be diagnosed from the 12 week pregnancy scan but is more likely to be found during the anomaly pregnancy scan that is done at around 20 weeks. If it is not detected by scans then it will be detected when a baby is born.

What problems can spina bifida cause?

Despite the surgical repair there are often long-term effects due to the poor development of the nervous system in this area.

Damage can result in a range of problems. The problems of spina bifida vary greatly for each child and often only become apparent as children grow and develop. The severity of the symptoms of spina bifida usually depends on the following 2 factors:

• How high up the spine the opening occurs. An opening at the top of the spine will cause problems such as weakness and loss of sensation higher up the body, compared with openings in the middle or at the base of the spine.
• Whether hydrocephalus is also developed, which can put pressure on the brain and cause damage.

Types of problems

Spina bifida can cause a wide range of symptoms that can be grouped into 3 general categories:

• Mobility problems, such as paralysis, muscle weakness and changes in sensation
• Bladder and bowel problems, such as bowel incontinence and urinary incontinence
• Cognitive problems, such as difficulty reading or solving problems

Mobility problems

Mobility problems are managed by neurology, physiotherapy and orthopaedic teams.

Most children with spina bifida will experience some degree of paralysis in their lower limbs which will affect walking. This paralysis can cause many associated problems. For example, this weakness can affect bone development. This can result in:

• dislocated joints
• misshapen bones
• abnormal curvature of the spine (scoliosis)
• difficulty mobilising

Bladder and bowel problems

Bladder and bowel symptoms are managed by the urology team and specialist nurses.

As well as controlling the limbs, the nerves that run throughout the spinal cord also control the bladder and bowel. Most people with spina bifida have little or no control over their muscles which keep urine and poo in, which causes them to experience urinary and bowel incontinence.

Urinary incontinence can take the form of a constant slow dribble of urine from the bladder. If left untreated, this can lead to infections and further kidney problems. An intermittent catheterisation with a small flexible tube is often needed to empty the bladder.

If your child has bowel incontinence, they may experience periods of constipation because they are unable to use their muscles to push the stool out of their bowel. This can then lead to diarrhoea or soiling due to poo overflowing from the bowel.

Cognitive problems

Cognitive symptoms are managed by neurology, psychology, education and occupational therapy.

Children with spina bifida can have learning disabilities which can affect cognitive functions such as difficulty with:

• attention span
• solving problems
• reading
• language
• organising and making plans
• co-ordination

It is difficult to predict how babies will be affected as they grow and develop. The specialist teams involved at the Sheffield Children’s will continue to asses and support you and your child as they grow and develop.

Hydrocephalus

Hydrocephalus is the build-up of fluid in the tubes deep within the brain. The excess fluid increases the size of the tubes and puts pressure on the brain. Children with spina bifida commonly develop hydrocephalus. If your child develops hydrocephalus, they will need treatment managed by the neurosurgical team at Sheffield Children’s.

How is spina bifida treated?

In most cases, surgery can be carried out to repair the defect. The neurosurgical team at Sheffield Children’s manage this surgery.

Spinal repair usually takes place within 48 hours after birth. This surgery will be done by the paediatric neurosurgical team here at Sheffield Children’s. Your baby will have a general anaesthetic and will be looked after by specialist paediatric anaesthetic team. During surgery, the neurosurgeon will place the spinal cord and any exposed tissues or nerves, back into your baby’s body. They will then close any gap in the vertebrae and seal the spinal cord with muscle and skin.

After the surgery, other specialities help with the management of associated symptoms and long term care.

Who will help care for my child?

If your child has spina bifida, these are some of the people who may be involved in your child’s care:

• neurosurgical team
• neonatal team
• urology team
• neurology team
• psychology team
• physiotherapy team
• occupational therapy team
• dietician team

After you go home we provide an outpatient service where you can see the team members all at one appointment.

A physiotherapist and or occupational therapist may assess and provide therapy treatment to help your child meet their full potential. Further corrective surgery may also be needed if your child develops these problems. This is done by the orthopaedic surgical team at Sheffield Children’s hospital.

What happens after the operation?

After surgery your baby will need to be nursed on their stomach for 5 days. During this time you will still be able to feed, cuddle and change your baby but most of your baby’s time will be spent on their stomach. This is done to protect the wound and help it to heal.

The wound will have a dressing on it. There will also be stitches that will need removing 10 to 14 days after surgery. The neurosurgical team will review the wound regularly. Antibiotic treatment will also be given to help the wound heal by preventing infection.

One of the physiotherapy team will come and assess your baby and give you advice on how to handle and position them.

What should I expect?

The outlook for children with spina bifida has improved significantly in recent decades. The specialist multidisciplinary team service at Sheffield Children’s helps children to be closely monitored as they develop.

These checks for complications means they can have treatment, therapy and support sooner. This lets children with spina bifida to meet their full potential. The majority of children with spina bifida will go on to full time education. Recreational and employment opportunities are also better now than at any time in the past.

It is proven that taking enough folic acid before you conceive and while you are pregnant can prevent up to 7 out of 10 cases of neural tube defects, such as spina bifida. However, it does not prevent all cases. You will be referred to our genetics team who will be able to give you further advice regarding future pregnancies and risk factors.