Spina bifida

Overview

Spina bifida is a type of birth defect in which the spine and spinal cord fail to develop correctly during the first month of pregnancy. The embryonic structure known as the neural tube is where the baby’s brain, spinal cord, and the tissues that surround them eventually develop.
Spina bifida affects babies by affecting the closure or development of a section of the neural tube, which results in issues with the spinal cord and the spine’s bones.
Different types of spina bifida includes:

  • Spina bifida occulta: Spina bifida occulta is a common and typically mild type of the condition, where one or more bones of the spine are slightly separated or have a small gap, but the skin covers the deformity. Many people with spina bifida occulta are unaware of their condition unless it’s detected incidentally on an imaging test performed for another reason. Spina bifida occulta usually only affects a small area of the spine, is asymptomatic, and typically does not require treatment.
  • Meningocele: Meningocele is a rare type of spina bifida that is characterized by a sac of spinal fluid bulging through an opening in the spine. The meninges, or the membrane surrounding the spinal cord, protrude through the opening, causing a lump or sac on the back. Although it’s more severe than spina bifida occulta, meningocele can be repaired through surgery with little or no nerve damage resulting. The surgery can be performed at any time during infancy, and the spinal cord is typically undamaged, meaning that the child has no neurological problems. While babies with meningocele may experience some minor problems with functioning, such as issues with bladder and bowel control, they generally have good outcomes with appropriate treatment.
  • Myelomeningocele: Myelomeningocele, also known as open spina bifida, is the most severe form of spina bifida, affecting nearly 1 in every 1,000 live births. In this condition, the spinal canal is open in the lower or middle back, causing the spinal nerves and membranes to protrude through the opening and form a sac on the baby’s back. This sac is typically not covered by skin, which exposes the nerves and tissues, making the baby vulnerable to life-threatening infections. Infants with myelomeningocele often develop hydrocephalus, which is caused by a defect at the base of the skull, known as Chiari malformation. Hydrocephalus refers to the accumulation of excess spinal fluid in the brain, which can result in severe damage to the brain, seizures, or blindness if left untreated. The recommended treatment for hydrocephalus involves the surgical insertion of plastic shunts beneath the skin, which can effectively drain the excess fluid into the abdominal cavity.

The severity of spina bifida can vary depending on factors such as the size, location, and type of defect, as well as any associated complications. While surgery can repair the spinal opening, if the nerve damage is not addressed, permanent disability may still occur. This condition is most found in the lower back or further down the spine.

Symptoms

Spina bifida signs and symptoms differ depending on the type, the severity, and the condition.

  • Spina bifida occulta: Spina bifida occulta usually does not result in any signs or symptoms as it does not impact the spinal nerves. However, there may be some visible indicators on the newborn’s skin just above the affected area, such as a small dimple, a patch of hair, or a birthmark. These skin abnormalities may suggest a spinal cord problem, which can be diagnosed through a magnetic resonance imaging (MRI) or spinal ultrasonography.
  • Meningocele: Bladder and bowel function may be affected by this type.
  • Myelomeningocele: This severe form of spina bifida is characterized by the spinal canal remaining open along multiple vertebrae in the lower or middle back. At birth, both the membranes and the spinal cord or nerves protrude, resulting in the formation of a sac. Typically, the tissues and nerves within the sac are visible, although in some cases, the sac may be covered by skin.

Myelomeningocele is commonly detected before or shortly after birth when treatment is readily available. A specialist team of healthcare providers should monitor children with this condition for the rest of their lives. Children diagnosed with this condition require ongoing monitoring by a specialized healthcare team, who will educate families on the various concerns to watch for throughout their lives. Since symptoms and problems are uncommon in children with spina bifida occulta, standard pediatric treatment is usually all that is required.

Causes

Despite ongoing research, the exact cause of spina bifida remains unknown, but some of the primary causes are believed to be a result of genetic, nutritional, and environmental factors. Examples of factors that might increase the risk of spina bifida include a family history of neural tube defects and a deficiency in vitamin B-9 (folate).

Risk factors

Despite the fact that there is no known cause for spina bifida, doctors and researchers have identified numerous risk factors. The following increases the risk in developing spina bifida.

  • Family history of neural tube defects: The chances of having another child with the same issue are slightly greater for couples who have already had one child with a neural tube defect. If the condition has previously affected two children, the chance rises. A woman who was born with a neural tube defect has a higher chance of giving birth to a child who has spina bifida than a woman who has no history. The majority of spina bifida patients are, however, born to parents who have no known history of the disorder.
  • Gender: Females are more affected than males.
  • Race: Spina bifida appears to be more common among individuals of European and Hispanic descent, compared to other ethnic groups.
  • Folate deficiency: The development of a healthy fetus requires an adequate supply of folate, which is the natural form of vitamin B-9. Folic acid, the synthetic form of folate found in fortified foods and supplements, can also contribute to meeting the body’s folate needs. Insufficient folate intake is a known risk factor for neural tube defects, including spina bifida.
  • Medications: During pregnancy, anti-seizure drugs such as valproic acid appears to result in neural tube abnormalities. They may prevent the body from using folic acid and folate.
  • Other diseases: A baby born to an obese or diabetic mother who has poorly managed blood sugar is more likely to have spina bifida.
  • Hyperthermia: During the first few weeks of pregnancy may raise the incidence of spina bifida. Spina bifida risk has been found to be marginally elevated in association with increases in core body temperature brought on by fever or usage of a sauna or hot tub.

It is advisable to inform the healthcare provider if you are using any drugs. Planning ahead may allow them to change some medications to reduce their risk of developing spina bifida.
It is also advisable for individuals who are aware of the risk factors for spina bifida to consult with their healthcare provider before getting pregnant to determine if they need a higher or prescription dose of folic acid.