Spina Bifida Types
Spina bifida is a heterogeneous group of neural tube defects that affect a fetus very early in development. Spina bifida occurs when the neural tube of the fetus does not completely close in the first 28 days post conception. The degree and positioning of the open cleft in the spine varies. There are three general classifications of spina bifida based on severity of the defect and physical manifestation.
spina bifida occulta (pronounced o-cult-tuh;)
As the most common form, often this condition is never detected because it is difficult to impossible to see such a small malady on ultrasound. This form of spina bifida happens when one or a couple of vertebrae are not completely closed. Often just one vertebra is affected. If more than one is affected, these vertebrae usually fuse abnormally with each other causing back stiffness. Nothing protrudes from the vertebral cleft and so there is rarely a physical disability associated with this form of spina bifida.
spina bifida meningocele (pronounced ma-nin-jo-seal;)
This is the rarest form of this neural tube defect. This type is characterized by a protrusion of the protective coating around the spinal cord through the cleft or hole in the vertebrae. Sometimes just the membrane protrudes, but more often the spinal fluid fills the protrusion causing a cyst-like structure on the child’s back. Surgeons can repair and remove this cyst, although there may still be some damage to the spinal cord. There are usually minor physical disabilities associated with this form of spina bifida including incontinence issues.
spina bifida myelomeningocele (pronounced my-low-ma-nin-jo-seal;)
This type is the most serious form of the birth defect. Not only does the membrane protrude from the vertebral cleft, but the spinal cord also pushes through the hole. This buckling of the spinal cord causes a great deal of damage and creates lifelong physical disabilities. In addition, because the spinal cord is not one straight cord through the spinal canal, the hindbrain is often pulled downward into the canal, causing severe compression of the cord and at times, brain damage. The hindbrain in the spinal canal can also cause a blockage of spinal fluid flow which results in a dangerous condition called hydrocephalus. Hydrocephalus often causes various levels of brain damage. A child with this form of spina bifida will usually have learning disabilities as well as paralysis or major physical difficulties.
Dr. Bernstein MD Chief of Pediatric Orthopedics Surgery explains about the different types of Spina Bifida