Spina bifida is a group of congenital conditions involving the failure of normal development of the spinal cord and vertebrae. There are three main types of spina bifida, the most severe being myelomeningocele and the most mild being spina bifida occulta. Spina bifida will often result in varying degrees of weakness to the legs. This muscle imbalance can then lead to the development of musculoskeletal problems, such as hip dislocation, joint contractures and clubfeet.

Types of Spina Bifida

Myelomeningocele

This is the most common defect of the developing brain and spinal cord, called the neural tube. This birth defect develops by the third week of fetal gestation. Myelomeningocele is a fluid-filled area formed by the lining of the spinal cord and a web of spinal nerves. A child born with myelomeningocele presents with a fluid-filled sac to the back. There is most often a defect in the skin as well, with no skin covering the mass. The bones of the spine fail to develop and do not close around the spinal cord. The sac protrudes through this defect and contains spinal nerve roots. The child born with myelomeningocele will have a degree of muscle weakness and differences in skin sensation related to the level of the spinal cord involved.

Lipomeningocele

This type of spina bifida is associated with an overlying fatty tumor. At birth, the skin is intact over the underlying spinal cord and vertebral anomaly. There is associated muscle weakness and decreased sensation, relevant to the level of the spinal cord involved. The lower the spinal cord defect, the higher the level of physical functioning.

Spina Bifida Occulta

Typically an incidental finding, spina bifida occulta rarely presents with symptoms. The lowest lumbar vertebra is found to have a small midline defect. This spinal cord and spinal contents are not affected in this condition. A child with this finding on an X-ray is expected to have no physical limitations, muscle weakness or increased risk of developing progressive spinal pathology. There is no need for routine checkups or activity limitations in the absence of symptoms. A child could grow up and never know that he or she has this defect.

What are the signs and symptoms of spina bifida?

Spina bifida is typically screened for during routine prenatal exams. Many cases of spina bifida are detected with prenatal sonogram and blood work.

• A midline vertebral body defect or cystic spinal cord lesion

• Elevated maternal alpha-fetoprotein

If the diagnosis is not made prenatally, the newborn baby may present with:

• A fatty or fluid-filled mass to the lower back

• A hairy patch or lumbosacral skin marking

• Weakness in the legs

What are the risk factors of spina bifida?

Factors that increase the risk of a mother having a child with spina bifida include:

• Having a child or sibling with spina bifida

• Having spina bifida herself

• Deficit of folate (folic acid) in the maternal diet before pregnancy

• Exposure to certain medications while pregnant (valproic acid)

Spina Bifida Diagnosis

The open neural tube defects are typically diagnosed prenatally. Those not diagnosed through prenatal sonogram and maternal blood work are diagnosed by physical exam at birth.

Spina Bifida Treatment

In the cases where an open myelomeningocele is present, surgery by a neurosurgeon is done within the first 48 hours of life. This surgery involves closure of the defect.

The musculoskeletal imbalances resulting from spinal cord defect are managed with a combination of physical therapy for strengthening and stretching, braces to support the knees and ankles while standing, and surgery to correct any problem bony misalignment.

The development of pressure sores is common. Daily skin checks and avoiding pressure from sitting and walking without proper support are taught at an early age.

Assistive devices are often used to support mobility.

There are many specialists involved in the care of a child with spina bifida. These children are often best managed through a multidisciplinary approach, involving neurosurgery, orthopaedics, urology, orthotics, physical therapy, occupational therapy, primary care, nutrition and neuropsychology.